[House Hearing, 109 Congress]
[From the U.S. Government Publishing Office]




QUESTIONS SURROUNDING THE 'HOCKEY STICK' TEMPERATURE STUDIES: 
IMPLICATIONS FOR CLIMATE CHANGE ASSESSMENTS


HEARINGS

BEFORE THE

SUBCOMMITTEE ON OVERSIGHT AND INVESTIGATIONS

OF THE 

COMMITTEE ON ENERGY AND 
COMMERCE
HOUSE OF REPRESENTATIVES


ONE HUNDRED NINTH CONGRESS

SECOND SESSION


JULY 19 AND JULY 27, 2006

Serial No. 109-128

Printed for the use of the Committee on Energy and Commerce







Available via the World Wide Web:  http://www.access.gpo.gov/congress/house



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                     COMMITTEE ON ENERGY AND COMMERCE
                       Joe Barton, Texas, Chairman           
Ralph M. Hall, Texas                       John D. Dingell, Michigan                         
Michael Bilirakis, Florida                  Ranking Member                    
  Vice Chairman                            Henry A. Waxman, California
Fred Upton, Michigan                       Edward J. Markey, Massachusetts
Cliff Stearns, Florida                     Rick Boucher, Virginia
Paul E. Gillmor, Ohio                      Edolphus Towns, New York
Nathan Deal, Georgia                       Frank Pallone, Jr., New Jersey
Ed Whitfield, Kentucky                     Sherrod Brown, Ohio
Charlie Norwood, Georgia                   Bart Gordon, Tennessee
Barbara Cubin, Wyoming                     Bobby L. Rush, Illinois
John Shimkus, Illinois                     Anna G. Eshoo, California
Heather Wilson, New Mexico                 Bart Stupak, Michigan
John B. Shadegg, Arizona                   Eliot L. Engel, New York
Charles W. "Chip" Pickering,  Mississippi  Albert R. Wynn, Maryland
  Vice Chairman                             Gene Green, Texas
Vito Fossella, New York                    Ted Strickland, Ohio
Roy Blunt, Missouri                        Diana DeGette, Colorado
Steve Buyer, Indiana                       Lois Capps, California
George Radanovich, California              Mike Doyle, Pennsylvania
Charles F. Bass, New Hampshire             Tom Allen, Maine
Joseph R. Pitts, Pennsylvania              Jim Davis, Florida
Mary Bono, California                      Jan Schakowsky, Illinois
Greg Walden, Oregon                        Hilda L. Solis, California
Lee Terry, Nebraska                        Charles A. Gonzalez, Texas
Mike Ferguson, New Jersey                  Jay Inslee, Washington  
Mike Rogers, Michigan                      Tammy Baldwin, Wisconsin
C.L. "Butch" Otter, Idaho                  Mike Ross, Arkansas
Sue Myrick, North Carolina
John Sullivan, Oklahoma
Tim Murphy, Pennsylvania
Michael C. Burgess, Texas
Marsha Blackburn, Tennessee
                          Bud Albright, Staff Director
                         David Cavicke, General Counsel
            Reid P. F. Stuntz, Minority Staff Director and Chief Counsel
                               __________
                               

                  SUBCOMMITTEE ON OVERSIGHT AND INVESTIGATIONS
                        Ed Whitfield, Kentucky, Chairman
Cliff Stearns, Florida                       Bart Stupak, Michigan  
Charles W. "Chip" Pickering,  Mississippi     Ranking Member
Charles F. Bass, New Hampshire               Diana DeGette, Colorado
Greg Walden, Oregon                          Jan Schakowsky, Illinois
Mike Ferguson, New Jersey                    Jay Inslee, Washington
Michael C. Burgess, Texas                    Tammy Baldwin, Wisconsin
Marsha Blackburn, Tennessee                  Henry A. Waxman, California
Joe Barton, Texas                            John D. Dingell, Michigan
  (Ex Officio)                                (Ex Officio)



                                 II




















                                    CONTENTS


                                                              Page
Hearings held:

   July 19, 2006.........................................        1
   July 27, 2006.........................................      603
Testimony of:
   Wegman, Dr. Edward J., Center for Computational 
    Statistics, George Mason University..................       39
   North, Dr. Gerald R., Department of Atmospheric 
    Sciences, Texas A&M University.......................       52
   Karl, Dr. Thomas R., Director, National Climatic 
    Data Center, National Oceanic and Atmospheric 
    Administration, U.S. Department of Commerce..........      127
   Crowley, Dr. Thomas J., Nicholas Professor of Earth 
    Science, Duke University.............................      138
   von Storch, Dr. Hans, Director of Institute for Coastal
    Research, GKSS Research Center, Germany..............      215
   McIntyre, Stephen, Toronto, Ontario, Canada...........      236
   Mann, Dr. Michael E., Associate Professor and 
    Director, Earth System Science Center, The 
    Pennsylvania State University........................      640
   Christy, Dr. John R., Professor and Director, Earth 
   System Science Center, NSSTC, University of Alabama 
    in Huntsville........................................      654
   Cicerone, Dr. Ralph J., President, National Academy 
   of Sciences...........................................      674
   McIntyre, Stephen, Toronto, Ontario, Canada...........      682
   Gulledge, Dr. Jay, Senior Research Fellow, Pew Center 
    on Global Climate Change.............................      696
   Wegman, Dr. Edward J., Center for Computational 
    Statistics, George Mason University..................      705
Additional material submitted for the record:
   North, Dr. Gerald R., Department of Atmospheric 
    Sciences, Texas A&M University, response for the 
    record...............................................      586
   Crowley, Dr. Thomas J., Nicholas Professor of Earth 
    Science, Duke University, response for the record....      585
   Mann, Dr. Michael E., Associate Professor and Director, 
    Earth System Science Center, The Pennsylvania State 
    University, response for the record..................      764
   Christy, Dr. John R., Professor and Director, Earth 
    System Science Center, NSSTC, University of Alabama 
    in Huntsville, response for the record...............      770
   Cicerone, Dr. Ralph J., President, National Academy 
    of Sciences, response for the record.................      780
   McIntyre, Stephen, Toronto, Ontario, Canada, response 
    for the record.......................................      784
   Wegman, Dr. Edward J., Center for Computational 
    Statistics, George Mason University, response for 
    the record...........................................      829


























 
QUESTIONS SURROUNDING THE 'HOCKEY STICK' TEMPERATURE STUDIES: 
IMPLICATIONS FOR CLIMATE CHANGE ASSESSMENTS 


WEDNESDAY, JULY 19, 2006

HOUSE OF REPRESENTATIVES,
COMMITTEE ON ENERGY AND COMMERCE,
SUBCOMMITTEE ON OVERSIGHT AND INVESTIGATIONS,
Washington, DC.


The subcommittee met, pursuant to notice, at 10:07 a.m., in Room 2123 
of the Rayburn House Office Building, Hon. Ed Whitfield (Chairman) 
presiding.
	Members present:  Representatives Walden, Bass, Stearns, 
Burgess, Blackburn, Barton (ex officio), Stupak, Schakowsky, Inslee, 
Baldwin, Waxman, and Whitfield.
	Staff present:  Mark Paoletta, Chief Counsel for Oversight and
 Investigations; Peter Spencer, Professional Staff Member; Tom Feddo, 
Counsel; Matt Johnson, Legislative Clerk; Mike Abraham, Legislative 
Clerk; Ryan Ambrose, Legislative Clerk; David Vogel, Minority Research 
Assistant; Chris Knauer, Minority Investigator; Lorie Schmidt, Minority
 Counsel; and Edith Holleman, Minority Counsel.
	MR. WHITFIELD.  I call this hearing to order this morning.
	Albert Gore's first movie, or documentary, entitled "An 
Inconvenient Truth" is the most recent of many topics in years and 
years of focus on the subject of global warming, and 95 percent of the
 American people certainly are familiar with the term "global warming" 
and they know basically what it means, I would think.  However, 95 
percent of the American people and certainly 95 percent of the Members
 of the U.S. Congress have not had the time to examine the data used by
 scientists, paleoclimatologists, and statisticians nor do they have 
the inclination to do so, to look at that data that is used to predict
 the probability that the temperature of one century is warmer or 
cooler than that of another century.
	Now, the United Nations Intergovernmental Panel on Climate 
Change is the world body with most of the interest and does focus on 
this subject of global warming.  And it is the body that most people 
look to on this subject.  Now, for many years the Intergovernmental 
Panel on Climate Change used a chart that clearly shows the 
temperature from 1000 A.D. to about 1450 A.D., that the temperatures 
during that period were significantly warmer than the latter part of 
the 20th Century, or the late 1990s.  Now, in 1998 and 1999, a
 paleoclimatologist, Dr. Michael Mann, with Raymond Bradley and 
Dr. Malcolm Hughes, introduced a new technique to develop more 
quantitative estimates of the nature of climate change since 1000 
A.D. and concluded that the late 20th Century was the warmest in 
1,000 years, that the warming during the late 1990s was the warmest 
in over 1,000 years.  Now, as a result of that report, the IPCC 
incorporated the study with other data which eliminated the warming 
period for 1000 A.D. to 1450 A.D. and incorporated a new graph 
referred to as the "hockey stick" graph, which shows remarkable
 warming in the late 1990s.  Now, when Chairman Barton and I wrote a 
letter asking that the Mann report be reviewed by some statisticians, 
there was a hue and cry around the country among many people in the 
news media that we were being totally political, that all we were 
trying to do was gut this issue that global warming is occurring.  
But I think quite sincerely that we have a responsibility when public 
policy decisions being made on reports like the Mann report and others 
have such a broad impact on so much of our society and certainly the 
Kyoto arguments were primarily based on this new chart, that the U.S. 
should be part of Kyoto.  That was an important part of that.  And so 
what we did was, we asked that Dr. Wegman and a team that he had review 
these data.  Now, when we did that, Sherry Boehlert, who is a good 
Republican friend of ours and is Chairman of the Science Committee, 
was quite upset about it and he said I think you all are being 
political also, and he asked that we ask Dr. North, who is going to 
be a witness, and would like for him to be involved in this data 
analysis, and he is going to be a witness today also.  But the real 
purpose of this is that this issue is so important that I think it 
is imperative that we hear from all sides and try to get some real
 understanding of the strengths and weaknesses of these reports. 
	Now, Dr. Wegman is going to testify today that the mathematics 
used by Mann is incorrect and wrong.  Dr. North, I think on page five 
of his testimony, says that they have some concerns about it, the 
math.  But the first witness today is going to be Dr. Edward Wegman, 
a statistician from George Mason University, and on his team was Dr. 
David Scott from Rice University and Dr. Yasmin Said from Johns 
Hopkins, and she is sitting behind him there.  Dr. Wegman is Chairman 
of the National Academy of Sciences Committee on Applied and 
Theoretical Statistics, and at the committee's request he assembled 
this ad hoc committee of statisticians to examine the hockey stick 
studies and related articles and his committee report prepared for 
Chairman Barton and me and the committee and publicly released this 
Friday provides important findings for Congress and the public to 
consider about the soundness and openness of climate change research 
and assessment and I can tell you right now that his document has 
been peer reviewed also, and we will get into that later.
	In addition to Dr. Wegman, we have Dr. Gerald North of
 Texas A&M University, who will testify on the first panel about 
the current state of historical temperature understanding.  Dr. 
North chaired a recent National Research Council panel on 
historical temperature reconstructions and we look forward to 
hearing his perspective for improving climate change assessments.  
And to help us understand some particulars of the IPCC process, we
 will hear testimony on the second panel from Dr. Thomas Karl, who 
is a coordinating author of the chapter upon which Dr. Mann and his
 colleagues worked.  Dr. Thomas Crowley of Duke University will be 
here and Dr. Hans von Storch, who traveled from Germany to be with 
us this morning.  Both will provide their views concerning the 
questions about the hockey stick study as well as questions 
concerning data sharing, transparency and the IPCC process.
	Finally, I would like to welcome Mr. Stephen McIntyre, who 
will testify about attempting to understanding just what was behind 
the hockey stick graphic promoted by the IPCC.  His work is a 
testament to the value of open debate and scrutiny.
	Now, I have talked about Dr. Mann and we invited Dr. Mann to 
be here today and he was unable to be here.  We are extending another
 invitation for him to come and hope that maybe he will be here next 
week.  Now, even though Dr. Mann could not come, he specifically 
asked us to request Dr. Crowley to testify on his behalf and Dr. 
Crowley is with us today from Duke University, and we look forward 
to his testimony.  But as I said, the real purpose of this hearing 
is, let us just open the book.  Let us look at everything.  Let us 
look at the criticisms of all parties and see exactly where we are 
on this important issue of global climate change.
	[The prepared statement of Hon. Ed Whitfield follows:]

PREPARED STATEMENT OF THE HON. ED WHITFIELD, CHAIRMAN, SUBCOMMITTEE 
ON OVERSIGHT AND INVESTIGATIONS

Good morning and welcome. We convene this hearing today to consider 
questions that begin with and surround the reliability of two
 particular studies of historical temperatures that gained an 
extraordinary level of public prominence a few years ago, and 
recently featured in former Vice President Al Gore's motion 
picture, "An Inconvenient Truth."  
In 2001, the results of these studies were used to promote the view 
that the very recent average temperatures of the northern hemisphere 
were likely the warmest in 1,000 years.   The temperature history 
results were portrayed in what is widely known as the 'hockey stick' 
graph, for its resemblance to the shape of a hockey stick.  As a 
result, these studies are known as the "hockey stick" studies.
With its relatively long and even trend for 900 years and then sharp 
up-tick during the 20th Century, the "hockey stick" graph effectively
 undermined what had been the prevailing view that we had experienced 
periods of similar or even higher average temperatures in the past -
 such as when the Vikings inhabited Greenland.  
The fact that the United Nation's Intergovernmental Panel on Climate 
Change, or IPCC, prominently relied upon the graph lent the graph its 
apparent authority.  The IPCC is an influential international body 
that conducts scientific assessments for use by policymakers. 
The graph offered a simple and powerful message for the public 
and policymakers to understand.  It was also a message that some say
 may have been based on faulty methodology.  The "hockey stick" 
studies formed the basis for the IPCC finding in 2001 that the 
1990s were likely the warmest decade of the millennium and 1998 
likely the warmest year during that time. Some of today's witnesses 
will describe in detail that the "hockey stick" studies were 
critically flawed and could not support the findings reached by 
these studies.  
Had the 'hockey stick' studies remained in the niche of climate 
change journals, we would not be holding this hearing.  Instead, we 
are here because the questions surrounding these studies relate 
directly to the strength of the findings in the first place.  What 
does the "hockey stick" story say about the reliability of these 
studies for policymakers?  
Last summer, Chairman Barton and I inquired into this matter after 
we learned that the lead author of these federally funded studies - 
Dr. Michael Mann -- to share the computer code he used to generate 
his results with researchers who sought to replicate the result of 
Mann's studies.  The researchers, one of whom will testify today, 
reportedly could not replicate his work based on what the study 
said. The researchers nevertheless identified several methodological 
and data problems with the work.  
How critical were these problems identified by these researchers?  
Were the problems undetected because Dr. Mann assessed his own work 
in an IPCC report? 
These are serious questions, and the answers contain broad 
implications for global policy on climate change. We should ensure 
that science is providing us with reliable, balanced, well-
considered, and unbiased answers.  
Today, our witnesses will help us address these critical questions. 
I want to welcome, especially, Dr. Edward Wegman, a statistician 
with George Mason University, who will lead off the first panel this 
morning.  Dr. Wegman is Chairman of the National Academy of Sciences 
Committee on Applied and Theoretical Statistics. At the Committee 
request, Dr. Wegman assembled an ad-hoc committee of statisticians 
to examine the hockey stick studies and related articles.  His 
committee's report, prepared for Chairman Barton and me and publicly 
released this past Friday, provides important findings for Congress - 
and the public - to consider about the soundness and openness of 
climate change research and assessments.   The Wegman Committee not 
only identified fundamental flaws in the "hockey stick" studies, it 
also addressed the larger point that climate change studies, like 
any work with potentially large policy implications, must be subject 
to careful and broad scrutiny.   
Dr. Wegman and his team performed their work completely independent 
of the Committee and without charge.  I believe Dr. Wegman's team has 
done a great public service and their work should help us improve how 
we discuss climate change when crafting policy. 
Additionally, Dr. Gerald North, of Texas A&M University, will testify 
on the first panel about the current state of historical temperature
 understanding. Dr. North chaired a recent National Research Council 
panel on historical temperature reconstructions, and I look forward to 
hearing his perspective for improving climate change assessments. 
To help us understand some particulars of the IPCC process, we'll 
hear testimony on the second panel from Dr. Thomas Karl, who was a
 coordinating author of the chapter upon which Dr. Mann and his 
colleagues worked.  Dr. Thomas Crowley, of Duke University, and 
Dr. Hans von Storch - who traveled from Germany to be with us this 
morning - both can provide their considered views concerning the 
questions about the "hockey stick" studies, as well as questions 
concerning data sharing, transparency, and the IPCC process. 
Finally, I'd like to welcome Mr. Steven McIntyre.  Mr. McIntyre will
 testify about attempting to understand just what was behind the 
hockey stick graphic promoted by the IPCC.  His examination of the 
facts underlying the assessments' claims really initiated some of 
the important questions concerning the scrutiny provided by climate 
change assessments.  His work is a testament to the value of open 
debate and scrutiny.  His perseverance should be commended.  
Let me add that we did invite Dr. Mann to this hearing, but his 
attorney explained that he was unavailable, on family vacation.  
Dr. Mann suggested Dr. Crowley could come in his place.   We do 
hope to have Dr. Mann at a future hearing, however. 
At the end of the day, the issues of climate change require open 
and objective discussion.  Some of the work we'll consider today 
points to the value of policy decisions that are informed by sound 
science and objective advice. 
I'll now yield to Mr. Stupak, our ranking member, for his opening 
statement. 

	MR. WHITFIELD.  At this time, I would like to recognize 
Mr. Stupak of Michigan for his opening statement.
	MR. STUPAK.  Thank you, Mr. Chairman.
	It is a little bewildering to me why the committee is holding 
its very first hearing on global warming to referee a dispute over a 
1999 hockey stick graph of global temperatures for the past 
millennium.  Mr. Chairman, in your opening statement you claim that
 Dr. Mann's hockey stick report of 1999 was the basis for the Kyoto 
Accord.  According to my recollection, Kyoto was in 1997, so it could 
not have been the basis for the Kyoto Accord.
	So as we will hear at this hearing today, global warming 
science has moved on since Dr. Mann put forth his study in 1999.  
Dr. Mann, who did this study, has made changes and even such diehard 
opponents as President Bush now actually admit that global warming 
exists and must be addressed.  Congress is particularly ill-suited 
to decide scientific debates.  There has been no attempt by this 
committee to obtain an unbiased view of the work done by Dr. Michael 
Mann, the author of the hockey stick research.  Dr. Mann, who has 
done additional work with his methodology since 1999, is not even 
here to confront his critics because the Majority would not even 
postpone this hearing until Dr. Mann could be available.  Moreover, 
it was known from the beginning that Dr. Mann used a new methodology 
and proxy material to reconstruct temperatures.
	Paleoclimatologists, those who try to reconstruct ancient 
climates, are not working with instrumental measurements of 
temperature as we have today.  Paleoclimatologists are looking at 
tree rings, ice cores, bore heads and historical records to attempt 
to determine what happened in an earlier time.  That is all the 
research materials paleoclimatologists have and it is an admittedly 
imprecise science.  It should not surprise us if the initial work in 
a new field can be improved.  What should surprise us is that 
Dr. Wegman's report focuses on critiques of Dr. Mann's first work 
in 1998 and 1999, even though the field of large-scale temperature
 reconstruction has advanced since that time.
	The Majority paid for a report to independently verify the 
critiques of Dr. Mann's 1999 research by a statistician but without 
any input from a climatologist.  The Majority left it to the Science
 Committee to ask the National Academy of Sciences to do a full 
review of all the science represented.  The Majority made no effort 
to verify whether the patterns in global temperatures detected in 
the Mann study were valid or coincided with conclusions of other 
researchers in global warming.
	It is now 7 years since the original work was published and 
much additional work has been done by Dr. Mann and others.  As we 
will hear from Dr. North, who chaired the NAS study, the patterns 
were verified with certainty for recent years but less certain for 
the years 1000 to 1600 A.D.  That is to be expected because there is 
less data from this long ago era.  Dr. Wegman has an eminent 
background in statistics and he believes that statisticians should 
be included in the research teams of all these studies because 
statisticians can make studies better.  Perhaps they can.  
Dr. Wegman says Dr. Mann didn't center his data properly.  Perhaps he 
didn't.  But we note that Dr. Wegman's work is not yet published or 
peer reviewed so it is very difficult for us to evaluate his work.  
Dr. Wegman's criticism of Dr. Mann should have been interdisciplinary 
and include a statistician can also be said of Dr. Wegman's work.  
Dr. Wegman did not have a climate scientist on his team.  However, 
Dr. Wegman has decided to go beyond his statistical expertise to 
hypothesize that Dr. Mann was allowed to publish and defend his work 
because of the small "social network" of paleoclimatologists who 
work with each other and protect each other.  I want to emphasize 
that this is simply a hypothesis.  Mr. Chairman, whatever the purpose 
of this hearing is, it is not to hypothesize about the impact of 
professional scientific relationships on research unless we have 
some hard objective evidence.
	We in Washington know all about undue influence on government
 scientists.  A political appointee at NASA just recently tried to 
keep James Hanson, a veteran atmosphere scientist, from discussing 
the dire consequences of global warming by threatening dire 
consequences to Mr. Hanson's employment status.  The science content 
has been changed on NASA and other government websites because it 
didn't fit the Administration's world view.  This fact ought to be 
of much more interest to this committee, the Oversight and 
Investigations Committee, than hypothesis about scientific social 
networking.
	And with that, Mr. Chairman, I would yield back the balance 
of my time.
	MR. WHITFIELD.  Mr. Stupak, thank you.  I also want to thank 
you for pointing out an incorrect statement that I made.  I said 
something about the hockey stick being the impetus for Kyoto.  Kyoto 
certainly started way before the hockey stick but the hockey stick 
graph did add impetus to the argument for the adoption of Kyoto, so I 
want to thank you for that.  Also, I would point out that the committee 
did not pay Mr. Wegman for this report, we simply contacted him asking 
him to review it.
	At this time I recognize the full committee Chairman, Mr. Barton.
	CHAIRMAN BARTON.  Thank you, Mr. Chairman.  I have a written
 statement, I am going to use some of it, but I want to speak 
extemporaneously briefly based on what my good friend from Michigan, 
Mr. Stupak, just said.
	The purpose of oversight and investigation is to do exactly 
that, to oversee the jurisdictional issues before this committee and 
when it seems to be called for to investigate issues that arise because 
of the oversight.  There has been a disagreement for a number of years 
in the community at large about the issue of global warming.  In this
 Congress, there has been a disagreement between the Chairman of the
 Science Committee and myself about that issue.  That is normal and 
that is not anything that is a negative.  But there were some 
statements made about a specific report by a number of people that 
basically use that report to come to the conclusion that global 
warming was a fact and that the 1990s was the hottest decade on 
record and that one year, 1998, was the hottest year in the 
millennium.  Now, a millennium is a thousand years.  That is a pretty 
bold statement.  So Chairman Whitfield and myself decided, let us take 
this report that is the basis for many of these conclusions and has 
been circulated widely and once it is in the mainstream, it is 
stipulated that because of that, everything else follows and let us 
see if it can be replicated.  Let us see if in fact the facts as 
purported in that report are in truth the facts.
	Now, I have not seen Dr. Wegman until I walked in this room.  
I have not talked to him on the phone or in person or any of his
 collaborators.  I may have seen Dr. North at Texas A&M since I went 
to Texas A&M.  I don't recall it but it is possible.  He has got 
enough white in his hair that I could have been one of his students 
and I wouldn't remember it, so I can't stipulate that I have never met 
him but I can stipulate that I have never met Dr. Wegman.  We asked to 
find some experts to try to replicate Dr. Mann's work.  Now, to their 
credit, when Dr. Wegman agreed to do it, he asked for no 
compensation.  I don't think we have even paid him for the fax paper 
that he has used.  He picked some eminent statisticians in his field 
and they studied this thing.  Had their report said Dr. Mann's data 
can be replicated, his conclusions are right on point, he is totally 
correct, we would have reported that, but that is not what they said. 
 Now, I took statistics at Texas A&M and I also took them in graduate 
school.  I made A's and B's, but I really didn't understand it but I 
kind of understand it.  And according to Dr. Wegman, Dr. Mann made a
 fundamental error.  He decentered the data.  Now, to the average 
person, that doesn't mean squat.  What does "decentered the data" 
mean?  What it means apparently is, he moved it off center a little 
bit by enough that it really makes a difference and then using some
 statistical techniques that instead of looking at all the variables 
and in a complex system like climate you are going to have lots of 
variables, he chose one or two as the principal variables and used 
those to explain everything else, and Dr. Wegman and his colleagues 
who as far as I know have got no axe to grind, have said the Mann 
study is flat wrong.  Now, it may be wrong just kind of 
unintentionally.  Dr. Wegman doesn't say there is any intent to 
deceive but he says it is flat wrong.  Now, if that is not the 
purpose of the Oversight Subcommittee of the Energy and Commerce 
Committee that has got jurisdiction over energy and environmental 
policy for the United States of America, then I don't know what 
this subcommittee should be doing.
	So I want to thank Dr. Wegman and his colleagues for giving 
us an unvarnished, flat out non-political report.  Now, admittedly, 
that report is going to be used probably for political purposes but 
that is not what he did, and I want to thank Dr. North for the work 
that he did in this document.  Now, it is a lot thicker than 
Dr. Wegman's document, and Dr. North and his colleagues have kind of 
looked at the same subject and they have come to a somewhat little--
they are little bit more, I don't want to use the technical term 
wishy-washy but they are kind of on both sides of it, but even
 Dr. North's report says that the absolute basic conclusion in 
Dr. Mann's work cannot be guaranteed.  This report says it is 
plausible.  Lots of things are plausible.  Dr. Wegman's report says 
it is wrong.
	Now, what we are going to do after today's hearing, we are 
going to take Dr. Wegman's report, and if my friends on the Minority 
want to shop it to their experts, so be it.  We are going to put it up 
there, let everybody who wants to, take a shot at it.  Now, my guess 
is that since Dr. Wegman came into this with no political axe to 
grind, that it is going to stand up pretty well.  If Dr. Mann and 
his colleagues are right, their conclusion may be right--Dr. Mann's 
conclusion may be right but you can't verify it from his statistics 
in his model so if Dr. Mann's conclusion is right, it is incumbent 
upon him and his colleagues to go back, get the math right, get the 
data points right, get the modeling right.  That is what science is 
about.
	So I want to thank you, Mr. Chairman, for holding this 
hearing.  I am planning to participate fully and extensively.  I have 
got a whole series of questions.  I stayed up half the night studying 
all the various documents so I hope that by the end of today we can 
shed some light on a subject that is very, very important to the 
future economic and health consequences for this country.  Thank 
you, sir.
	[The prepared statement of Hon. Joe Barton follows:]

PREPARED STATEMENT OF THE HON. JOE BARTON, CHAIRMAN, COMMITTEE ON 
ENERGY AND COMMERCE

Thank you, Chairman Whitfield.  Today's hearing on the hockey stick
 temperature studies will show why we need to question the quality 
of climate assessments for policy makers. 
This Committee frequently confronts some of our Nation's most 
consequential public policy questions affecting the quality of 
human health, our economy, and our environment.  However, no issue 
we deal with has more potential to affect the American people than 
climate change.   
Meanwhile, the compounding costs to the U.S. economy posed by some 
proposals for reducing greenhouse gas emissions could rock our economy, 
drive manufacturing off-shore, and spike domestic consumer energy costs. 
That is why we need to be sure that we have a solid factual basis for 
whatever decisions we make in this area. 
The report we are about to receive indicates that the social and 
statistical underpinnings of key climate-change work are prone to 
produce error.
I look forward to hearing from all of our witnesses because we have 
important work to accomplish today.  I would especially like to thank 
Dr. Edward Wegman who, on his own time and his own expense, assembled 
a pro bono committee of statisticians to provide us with independent 
and expert guidance concerning the hockey stick studies and the 
process for vetting this work.  
Dr. Wegman and his committee have done a great public service.  Their 
report, with clear writing and measured tone, has identified 
significant issues concerning the reliability of some of the climate 
change work that is transmitted to policymakers and characterized as 
well scrutinized.  The Wegman Committee report will be the centerpiece 
of today's hearing.  
These 'hockey stick' studies were the linchpin for what became widely
 acclaimed as the consensus view of the earth's temperature history 
during the past thousand years.  It was presented as part of the 
leading climate assessment for public policy makers around the 
world - the United Nation's Intergovernmental Panel on Climate 
Change, or IPCC.  
Both good science and good public policymaking demand that scientific 
work withstand independent and impartial scrutiny. Information that is 
not scientifically sound is just not acceptable.  Indeed, it appears 
that some of the authors of the IPCC assessment dealing with global
 temperature history were not independent or impartial. They also 
happened to be the authors of the hockey stick studies, themselves. 
The researchers then declined to provide the information necessary 
to replicate their work, a fundamental failure in reliable science. 
The "hockey stick" studies were supported by Federal grants and were 
central to a prominent finding in an influential assessment.  In my 
view, if Congress is going to make policy decisions based on the 
authority of climate change assessments, we cannot fail to wonder how 
they have been formulated.   Asking questions is at the core of what 
we do.
Our central question is: Can we count on hockey stick studies?  That 
answer from Dr. Wegman and his panel appears to be, "No."  And it 
doesn't appear to be a matter of overlooking the researchers' written 
caveats about their particular work; rather, the Wegman panel has 
identified a fundamental error of methodology.  If that finding holds 
up, it will highlight a mistake that lay dormant for years as a closed 
network of supportive colleagues saw and heard what it wanted. It took
 scientists outside the network to identify the core problems, both in
 the studies and in the IPCC assessment.
Congress is in the business of making policy decisions that affect 
the lives of real people.  Science provides us with the answers to 
many policy questions, and we need to trust it.  I do trust science, 
and I trust it most when it is transparent, open to question, and 
eager to explain.  When research is secretive, automatically and 
aggressively defensive, and self-reinforcing, it becomes easy to 
distrust.
As Chairman of the Energy and Commerce Committee, which holds a key 
role in any policy making relating to climate change, I believe it 
is incumbent on this Committee must ensure that the very best 
information is available to make its decisions.  
Caveats and uncertainty are facts of life, and not only in science. We 
deal with complicated science and research-based decisions and 
uncertainty in every area of our jurisdiction.  Some of the most 
troubling work we confront - on bioterror or radiological risks for 
example - present very tough and complicated issues for us to assess. 
Good science is built on healthy skepticism, and good scientists don't 
hide from questions. They invite them. Asking questions to establish 
the validity of scientific studies - especially those with enormous 
policy implications - is why we are here today.  The caveats and 
uncertainty are never going to be eliminated, but we would like to 
know whether the facts or caveats contained in these sophisticated 
climate assessments have been adequately and independently 
scrutinized.   
Heads-I-win, tails-you-lose science can produce any answer that is 
desired, but that's hardly the way to make multi-billion-dollar 
decisions.   This is a vitally important matter.  When we deal with 
global warming, we need to know that the underlying studies 
constitute reliable science.  The taxpayers depend on it.  My 
grandchildren depend on it.  The planet depends on it.
I want to extend my thanks to all the witnesses for appearing today, 
and I look forward to their testimony. 

	MR. WHITFIELD.  Thank you, Mr. Chairman.  At this time I 
recognize Mr. Inslee of Washington.
	MR. INSLEE.  Thank you, Mr. Chairman.
	America is fully capable of dealing with global warming but 
not if Congress engages in snipe hunts, arguments about how many 
statisticians can dance on the head of a pin rather than figuring out 
what our energy policy should be to get a handle on global warming.
	Now, why are we in this exercise for doubt?  I refer you to the 
first slide I have, which is a memo from the tobacco industry when they 
were fighting the clear, unalloyed science that tobacco was bad for 
you.  Here is a memo from one of their people:  "Doubt is our
 product."  And those who decide that America should stay quiescent,
 do nothing about global warming, doubt is their product.

	Next slide.  

Why should we deal with this?  What we are going to find out today, I 
hope, we can spend weeks debating the statistics behind one particular 
study but what we will find is that every single study ever that has 
looked at proxy data for temperature has indicated we are in a unique
 circumstance and carbon dioxide is going through the roof which you 
will see from these studies, multiple of which are on this slide.  
Next slide.


	What we find now is that CO2 is going through the roof.  No 
one in this room will say otherwise.  The first bottom circle is 
where we are today.  It is higher CO2 levels than any time in the 
last 160,000 years.  Every single scientist in the world agrees to 
that fact, and by 2100 the circle on top, it will be almost twice as 
it has ever been in the last 200,000 years.  Every single scientist 
in the world agrees to that fact, and because CO2 drives climate, 
because it drives temperature, we ought to get out of this posture 
of the ostrich and assume the posture of the eagle to do something 
about global warming.  Next slide, please.

	I want to point out something that is very important in today's
 discussion.  We can spend years debating what the temperature was on 
July 18, 972, but what we ought to know is that our putting CO2 into 
the atmosphere is destroying the world's oceans regardless of the 
temperature.  The new science shows that the CO2 that we put in the 
atmosphere is acidifying the oceans.  The oceans have 23 percent more 
hydrogen ions that create acidic conditions than any time ever that 
we know of in human history, at least.  Next slide, please.

	The result of that is that when the oceans become more acidic, 
it becomes much more difficult for any life including plankton, coral 
reefs, clams, oysters, you name it to form shells including plankton, 
which is the basis of the entire food chain of all the protein we get 
out of the oceans.  Next slide, please.

	What this shows is the pH level of acidity is changing.  Next 
slide, please.  

So that by the year 2099, conditions in the ocean may not support any 
coral reefs healthy anywhere in the world.  This doesn't have anything 
to do with Dr. Mann's report.  Even if temperatures did not change 
one-half a degree, the oceans are becoming acidic that may not support 
the protein that we depend on in the world if we don't act and if 
this committee continues to act like an ostrich.  Next slide, please.

	Why are Americans rejecting this doubt they see with their 
own eyes?  Polar icecaps shrunk in density--next slide, please--in the 
last 12 years. 

Greenland is melting at unprecedented rates.  Next slide, please. 

The polar icecap has shrunk 20 percent in the summer.  The red line 
shows where it used to be.  The white is where it is now.  Next 
slide, please.  We have run out of slides.  Well, maybe I ought to 
talk then.
	This is very disturbing to me that when the entire world 
scientific community has reached a conclusion with high levels of 
certainty that carbon dioxide is going to astrospheric levels, 
unprecedented in world history, and that when we know beyond a shadow 
of a doubt the levels of carbon dioxide ultimately will drive
 temperature changes to areas we do not want to see, that instead of 
really engaging Congressional talent in figuring out how to deal with 
this problem, we try to poke little pinholes in one particular 
statistical conclusion of one particular study where the overwhelming 
evidence is that we have to act to deal with this global challenge.
	It is not fitting for this Congress, America that should lead 
the technology that drives the energy future of the world, to sit here 
to ask these fine statisticians to go into mind-numbing detail about 
whether this particular year was hotter than it was in 980.  I don't 
care whether this year or yesterday was the hottest day.  It was 
pretty hot here yesterday, but I don't care whether it may have been 
hotter in 980.  What I care about is whether there will be snow in 
the mountains for my kids and grandkids to ski on 50 years from now, 
and there is not going to be unless this Congress pulls its head out 
of the sand and acts.
	So I look forward to the day that we have a Congress that will
 adopt the position that we need to deal with technology rather than
 statistical recreations of the tobacco industry's effort to create 
doubt.  Thank you.
	MR. WHITFIELD.  Mr. Bass.
	MR. BASS.  Thank you, Mr. Chairman, and thank you for holding 
this hearing.
	I want to start by saying that in my opinion, there is 
absolutely nothing inappropriate about the subject of this hearing, 
and although the data may be mind-numbing, nonetheless there are 
those--I am probably not one of them--who really get into going 
through the data and the details and so forth to try to figure out 
what the problem is.  Ultimately, the issue underlying the hearing 
today and any others that we have is not going to be about math, it 
is going to be about the effect of the extraction of enormous 
quantities of hydrocarbons from the middle of the Earth and from 
underground and the combustion of those hydrocarbons and the 
resultant impact that that has, if any, on the climate of the world.
	Now, in another life when I used to sell architectural panel 
products for buildings, I was often asked by a customer whether or 
not the panel that I was trying to sell passed the ASTM, American 
Society for Testing Materials, E84 test, and I always used to respond 
because, of course, we couldn't afford to have that test conducted, I 
used to say well, it hasn't but I subjected it to what I called the 
elephant foot test and I built--every fall I burned a huge pile of 
brush in my field on the farm I live on and one year I just took one 
of the panels that I planned to sell and I threw it on top of the pile 
and it sat there for 30 minutes and nothing happened.  Is that 
satisfactory?  Well, we can spend I think a productive period of time 
talking about the basis upon which the data was developed to determine 
the Mann report or the Wegman report or Dr. North's report and so 
forth, but ultimately I think we need to recognize that there is a 
problem and anyone who denies the existence of any problem associated 
with the release of these hydrocarbons I think really needs--I want to 
be friendly about this--really needs to rethink that premise.  There 
is something going on and I think finding out what that something is 
and then trying to debate a policy whereby we address that issue is
 constructive.
	So I want to thank my friend from Kentucky for holding this 
hearing and I look forward to hearing the witnesses' testimony, and I 
yield back.
	MR. WHITFIELD.  Thank you, Mr. Bass.  At this time I recognize 
Mr. Waxman of California.
	MR. WAXMAN.  Thank you very much, Mr. Chairman.
	The party that is in the majority selects the Chairman of the 
committees and the subcommittees and they can decide what priorities 
ought to be given to different issues and what hearings are to be 
called.  Now, in the past 12 years, we have had study after study 
after study raising genuine concern about global warming and climate 
change.  The Energy and Commerce Committee is a committee that has 
legislative jurisdiction over this issue.  So for the past 12 years 
this committee has a very amazing record on this issue.  This is only 
the second hearing in 12 years.  The first one was to look at the very
 intricate issue of modeling on predictions of climate change and this 
one is to look at studies from 1998 and 1999 to see whether those 
studies are refuted by the work of the two gentlemen before us today. 
We have not held a hearing looking at what is the overwhelming 
scientific consensus that global warming is real and is caused by 
humans.  We have not focused on some of the important recent 
scientific news on global warming such as a study showing that climate 
change is causing increased wildfires in the American West or the recent
 studies that show that global warming is leading to more intense 
hurricanes.
	The committee could go a step further by examining the practical
 solutions that could begin to reduce our greenhouse gas emissions, and 
if the committee leadership wanted to conduct important and nonpartisan
 oversight, it could investigate why a former employee of ExxonMobil 
operated out of the Bush White House to sow doubt in government 
publications on global warming.  Instead, this committee is doing what 
the deniers of global warming would have us do, ignore all the important
 questions and divert ourselves to a ridiculous effort to discredit a 
climate scientist and two studies he published eight years ago. 
	Chairman Barton began this dubious investigation in June of 
2005 when he sent a letter demanding the funding for every study that 
had ever been conducted by Dr. Michael Mann, demanding he turn over all 
of the data for all their research and made over burdensome and 
intrusive requests.  The Washington Post accused our Chairman of 
conducting a witch hunt.  The Chairman of the Science Committee, 
Sherwood Boehlert, called the investigation "misguided" and 
"illegitimate."  Well, oftentimes when we have scientific disputes we 
ask the National Academy of Sciences to review the matter.  Instead of 
asking them--even though they offered their services to help resolve
 controversy--the Academy wasn't called on by this committee but by
 Representative Boehlert's committee and the Academy issued its 
report last month and they found that they largely upheld the 
findings of Dr. Mann.
	So I have to submit that I don't find this hearing to be one 
about truth.  It is about sowing doubt and spreading disinformation, 
and I chaired all those committees over the years where I heard from 
tobacco executives who always insisted on having their scientists come 
in and say it is only coincidental that more cancers and other 
diseases seem to afflict smokers but there is no causal relationship. 
Not only is this hearing not legit in trying to deal with an important 
issue, it isn't even fair.  We are going to hear people attacking 
Dr. Mann but we are not going to have Dr. Mann here to confront the
 accusations against him.  That is not science where you hear only one 
side.  Science is hearing both sides, looking at the evidence, reaching
 conclusions based on the evidence.  Dr. Mann was willing to testify 
before the committee but his schedule would not be accommodated.  
Global warming is an incredibly serious problem and this is not a 
serious hearing.
	I would submit that if you have doubts, fine, but prudent 
people would start doing something in case your doubts on the 
Republican side of the aisle are wrong.  We would start taking 
measures to reduce these greenhouse gas emissions that seem to be
 causing enormous damage to our planet and a threat to human life. 
Instead, we are looking at reports from 8 years ago and trying to 
debunk them.  That is not an indication to me, that and the 12 years 
of inaction by this committee, that there is any interest on behalf 
of the Republican leadership to come to terms with what is not a 
partisan issue at all but one that is a very important issue for us 
to address.
	[The prepared statement of Hon. Henry Waxman follows:]


THE PREPARED STATEMENT OF THE HON. HENRY WAXMAN, A REPRESENTATIVE IN 
CONGRESS FROM THE STATE OF CALIFORNIA

Today, the Subcommittee holds only the second hearing on global 
warming in the Energy and Commerce Committee since the Republicans 
took over the House of Representatives in 1995.  With so many 
important aspects to global warming and twelve years of virtual 
inaction, there's a lot of important work for the Committee to do.
 	It could start by highlighting the overwhelming scientific 
consensus that global warming is real and is caused by humans.  Or 
it could focus on some of the important recent scientific news on 
global warming, such as the study showing that climate change is 
causing increased wildfires in the American West or the recent 
studies that show that global warming is leading to more intense 
hurricanes.
 	The Committee could go a step further by examining the 
practical solutions that can begin to reduce our green house gas 
emissions.  And if it wanted to conduct important and non-partisan 
oversight, it could investigate why a former employee of ExxonMobil 
operated out of the Bush White House to sow doubt in government 
publications on global warming.
 	Instead, the Committee is doing exactly what the big oil 
companies hope for it to do...it ignores the important questions 
and diverts to a ridiculous effort to discredit a climate scientist 
and a study he published eight years ago. 
Chairman Barton began this dubious investigation when he wrote 
Dr. Michael Mann and several other researchers in June 2005.  He 
demanded to know the source of funding for every study they had 
ever conducted, demanded they turnover all of the data for all of 
their research, and made other burdensome and intrusive requests.  
The Washington Post accused Chairman Barton of conducting a witch 
hunt.  The Chairman of the House Science Committee Sherwood 
Boehlert called the investigation "misguided" and "illegitimate."  
And the nation's premiere science organizations quickly condemned the
 investigation.  The American Association for the Advancement of 
Science wrote to Chairman Barton stating that his letters "give the 
impression of a search for some basis on which to discredit these 
particular scientists and findings, rather than a search for 
understanding."  
The National Academy of Sciences also weighed in, stating that 
Chairman Barton's approach was "intimidating" to researchers and 
offering the services of the Academy to help resolve the controversy.
Ironically, it wasn't Chairman Barton who took the Academy up on its 
offer.  Instead, Rep. Boehlert requested the Academy report that was 
released last month.  The Academy largely upheld the findings of 
Dr. Mann.
This hearing isn't about finding the truth.  It's about sowing doubt 
and spreading disinformation.  The closest parallel is the decades-
long campaign of the tobacco industry to deny that nicotine is 
addictive and cigarettes cause cancer.
And the hearing isn't even fair.  Today we're going to attack the 
work of Dr. Mann, but we're not going to give Dr. Mann a chance to 
confront the accusations against him.  Dr. Mann was willing to 
testify before the Committee, but his schedule was not accommodated 
and so he is going to be tried in absentia.  
Global warming is an incredibly serious problem, but this is not a 
serious hearing.  It's a diversion and a delaying tactic.  And - 
worst of all - it is a missed opportunity to begin the process of 
protecting our children from the catastrophic effects of global 
warming.  
I know that the Chairman of this Subcommittee has never accepted the 
science about global warming.  To bolster his argument over the years, 
he has repeatedly brought to the attention of the Committee, the views 
of Gregg Easterbrook and his book, "A Moment on the Earth."
So, I just want to make sure that the Chairman is aware of 
Mr. Easterbrook's op-ed from May 26, 2006, in which Mr. Easterbrook 
announces that he has changed from "a skeptic to a convert."  He says 
that it is "case closed," and that a strong scientific consensus shows 
that global warming "is a real phenomenon posing real danger."   
I am glad that Mr. Easterbrook has revisited his views and corrected 
them accordingly.  I hope the Chairman is willing to do the same. 

	MR. WHITFIELD.  Dr. Burgess, you are recognized. 
	MR. BURGESS.  Thank you, Mr. Chairman, for the recognition.  
I thank the Ranking Member for pointing out that partisanship has no 
place in this debate and I hope we won't see it again this morning.
	I will point out just for the record that Dr. Mann has been 
invited to appear before this committee before this hearing this 
morning.  He couldn't be here.  Apparently he is on vacation that 
couldn't be interrupted and maybe he can be here next week, and if 
he can be here next week, we will certainly be grateful to hear from 
him, but fortunately we do have his number one colleague, Dr. Crowley, 
on our second panel and I am grateful for that as I am sure the 
Minority is as well.
	Again, I thank the Chairman for the recognition and I want to 
thank all of our witnesses for taking their valuable time to be with 
us here today.  I know there are many other productive activities you 
could have been doing.  And we have already heard from our friends on 
the other side of the room that there does indeed currently exist an
 international consensus that global warming exists and that human 
beings have caused it.  They didn't say so but I would further 
extrapolate that it is Americans that have caused it and it is 
probably one American in particular and he lives in the White House. 
But I think it is fair to point out that no such consensus exists.
	The Earth has been heating and cooling for millions of 
years.  There have been big ice ages, little ice ages and it is fair 
to say that in between those two cooling events it probably even got 
a little warm.  The Earth's climate is cyclical and we have only been 
paying attention during the past few hundred years.  With the cyclical 
nature of the Earth's climate, it is plausible to say that the Earth's
 temperatures would be on the rise today regardless of what humans did
 or didn't do.  Thirty-five years ago, I was a freshman in a geology 
class and we learned how the Earth itself was spun off as a hot ball 
of gases and gradually cooled and it was postulated that the Earth had 
been cooling ever since and indeed perhaps Armageddon would come one 
day not as a fire or as a flood but as we cooled into that last ice 
age.  Now we have global warming staring us in the face.
	I am not saying we should completely dismiss fears of global 
warming as an inaccurate science.  I think that it merits thoughtful 
and serious debate and we owe the subject matter thoughtful and 
serious debate.  Part of my problem with the whole process is, that 
it seems that the cleaner we make our energy generation capability, 
and indeed we have cleaned our energy generation capability over the 
years, and the Ranking Member can take considerable credit for that 
with legislation that he has passed, but now we want to come up 
against an obstacle that nothing can come out of those pipes, we 
have already taken out the VOX, the NOX, the SOX, the POX, the TOX. 
Now it is the carbon dioxide and water that are coming out of those
 smokestacks that has to be stopped, and it is interesting that later 
today--we have a mechanism to stop the carbon dioxide from coming out 
of those stacks and later today we are having a hearing in the Energy 
and Air Quality Subcommittee of this same Energy and Commerce 
Committee on the Yucca Mountain nuclear waste repository.  One of the 
reasons why Yucca Mountain is so important is because of the increasing
 importance of nuclear power in our national fuel mix as an 
emissions-free, carbon-free-emissions source of power.
	In fact, I would submit that along with the passage of the Clean
 Air Act in the past few decades, perhaps one of the greatest missed
 opportunities--if the Clean Air Act was an enacted opportunity, one 
of the great missed opportunities was abandonment of nuclear power in 
the late 1970s and allowing other countries to get ahead of us in that 
regard so now that our dependence on foreign oil--and we knew in the 
1974 embargo that dependence on foreign oil was not a good foreign 
policy strategy and yet for whatever reason we have lagged with 
development of nuclear fuel, so I am grateful we are having that 
hearing later on today.
	It is false to presume that a consensus exists today or that 
human activity has been proven to cause global warming, and that is 
the crux of this hearing.  What we are here today to discuss is the 
broader issue of the use of sound statistical analysis and the peer 
review process through the lens of the hockey stick temperature 
studies, but the focus of our hearing today is to examine the 
statistical analysis and methodology used when evaluating the 
influential report on global warming written by Dr. Mann.  As the 
U.S. Congress and even the international policymaking bodies look 
to the scientific community to provide information and analysis, it 
is especially important to make certain that the processes are in 
place to ensure that we are using sound and unbiased science that 
has undergone rigorous peer review process.
	I would point out that simply turning off the electrical 
generation plants that provide the air conditioning back in my 
district would not be a viable option.  I would submit that the good 
people of California got upset when some people in Texas turned off 
their electrical generation plants a few years ago. I don't see that 
as a viable option.  Should we move to other methods?  Perhaps, but 
we need to do so in a sound and scientific manner.
	With that, Mr. Chairman, I will yield back.
	MR. WHITFIELD.  At this time I recognize Ms. Baldwin of--
okay, Ms. Schakowsky.
	MR. STUPAK.  Mr. Chairman, before we do that, if I may, I 
would like to put into the record a letter from Georgetown University
 Law Center Institute for Public Representation explaining why 
Dr. Mann cannot be here on such short notice from the committee and 
other dates he was available to testify.  I would like to put that 
in the record, a follow-up of the statements that he is on vacation, 
which is not true.
	MR. WHITFIELD.  We would be happy to do so unless--
	MR. STUPAK.  Thank you.
	MR. WHITFIELD.  --there is objection.  Is there objection to 
this going in?  Thank you.
	MR. STUPAK.  This letter of July 19 was provided actually by 
fax to Mr. Spencer and Mr. Paoletta.
	[The information follows:]
	MR. WHITFIELD.  Ms. Schakowsky.
	MS. SCHAKOWSKY.  Thank you, Mr. Chairman.
	I am glad that we are holding a hearing on global climate 
change although I am disappointed in the actual substance of this, and 
I have a statement for the record that is prepared but I would like to 
just say a couple of things extemporaneously about this issue which I 
care so much about.
	I guess I would ask about this particular hearing in some ways 
is, what is the point?  I think that there are certain agreements that 
all of the scientific community would adhere to, and one is that 
climate change, the question being how much does human activity 
contribute to that, but the climate change is definitely happening, 
that the Earth is warming right now and there is a large and robust 
body of science that documents that, that even in the Middle Ages it 
could have been as warm as now although that is not clear at all, that 
the temperature is going up and that climate change impacts are being 
observed now and are projected to be of enormous consequence, enormous
 consequence.  If the snow in the Himalayas melts, which provides 
water for I think close to a billion people, this is of great concern.
	As a grandmother, I am concerned that my grandchildren may 
never see or know about a polar bear in the wild and that the coral 
reefs are disappearing.  The fact that we are seeing stronger 
hurricanes and tornadoes and that there is drought and flood and 
hunger and displacement as a consequence, these are things that we 
know about, and so the question is, even if human activity is not 
the principal cause of global warming, which most scientists do 
believe that is the case, but even if it weren't but we are simply
 contributing to it, why wouldn't we be focusing on now how human 
activity could reduce the impact of global warming, how we could help 
to stem the tide of these devastating consequences that will hurt all 
of humanity.  Why wouldn't we be focusing on that instead of trying 
to discredit a report that is only one piece of the evidence that 
establishes that we are in the midst of a tremendous change that is 
going to impact the possibility of life as we know it on this planet.
	We don't have to be talking about the kinds of devastating 
changes in lifestyle that Americans won't accept.  Instead, because 
of our ingenuity, always being on the cutting edge of technology and 
change, we can manage the changes that are needed in order to sustain 
life on this planet.  It just makes no sense to me--I mean, we will 
talk about it and we will get into it how the Mann statistics that 
are going to be discredited actually weren't used in his final report 
and we can go into all the details back and forth about the scientific
 evidence but it seems to me that this is a waste of time, that what
 we ought to be talking about is how are we going to confront what 
everyone knows is a real problem, and if human activity can be changed 
in some way to ameliorate that problem, for the life of me I can't 
understand why all of us together in a bipartisan way wouldn't want 
to do that.
	I have a young person in my district who really is absolutely 
obsessed with the issue of global warming.  He is a junior high school
 student.  His mother is worried about him because he worries about 
it so much.  To me, the answer isn't explaining to him oh, be happy, 
don't worry, this isn't really an issue, there is nothing you can do 
about it.  The answer is, we need to tell young people, the next 
generation, my grandchildren, that there are things that we can do 
today, and so I plead with my colleagues on both sides of the aisle, 
let us get down to solutions, not discrediting one tiny piece of the 
mass of evidence that says that we are in trouble right now and that 
literally billions of people, all the people are on our plant, will 
suffer if we don't get down to the business of finding a solution, 
so I thank you, Mr. Chairman, for the time.
	MR. WHITFIELD.  Thank you.  Mr. Stearns, you are recognized 
for 5 minutes.
	MR. STEARNS.  Thank you, Mr. Chairman.  I think Mr. Stupak put 
in the letter of July 14 from Mr. Mann's lawyer.  I would like 
unanimous consent to put in the letter of July 13 that preceded that, 
which if without objection I would like that--
	MR. STUPAK.  Well, I guess I will have to object until we see 
it.  Can we at least see it?
	MR. STEARNS.  Oh, sure, sure.  Yes.  You put a letter that came 
after the first letter and I thought it would be appropriate if we 
include that letter too since that is a day earlier in which he said he 
could not make our committee and for whatever reason he couldn't make 
it and in fact he suggested that if we do have this hearing, that we 
should have Dr. Thomas J. Crowley, and indeed we took his advice and 
we got Dr. Crowley.  He is going to be on the second panel, so we 
took Dr. Mann's advice, we got the people he wanted, and I am sure, 
Mr. Chairman, other people had to cut their vacation short to be here, 
perhaps even Dr. North did.  This is a time when a lot of us are taking
 vacations, not necessarily Members of Congress who are into a 
campaign mode but the rest of you perhaps are doing that, and I can 
understand that, but the letter Mr. Stupak put in said that he would 
not even show up on the 27th.  The letter I am putting in says he won't 
show up today.  Unfortunately, his lawyer from the Georgetown 
University Law Center keeps talking about July--I think in his letter--
I don't have it in front of me but he has a typographical error in 
both letters in which he cites Friday, July 9.  In all calendars, 
July 9 is not a Friday.
	MR. WHITFIELD.  They are not objecting to the letter.
	[The information follows:]



	MR. STEARNS.  Okay.  Good.  All right.  Well, I was just 
talking to make sure Mr. Stupak had plenty of time to read it so that 
I could go forward.
	You know, I think almost everybody in this room and perhaps 
everybody on this oversight committee would agree that there is global 
warming of some kind.  The question is, is it sinusoidal, that is, are 
we looking at warming today in which there was warming like this or 
similar to this in the Middle Ages and have we seen a warming and a 
cooling much like a sinusoidal wave, and so we are trying to look at 
Dr. Mann's analysis and we are trying to say, is he absolutely right 
that we have this hockey stick effect that is just flat and then 
suddenly comes up.
	Now, we have Dr. Wegman's analysis concludes that Dr. Mann's 
work cannot support the claim that the 1990s were the warmest decade 
in the millennium.  I mean, that is what he is saying.  Some people 
are questioning Dr. Mann, his quantitative analysis, and that is fine. 
He could be right, he could be wrong.  Now, Dr. North, in looking 
through his testimony which he is going to give, he sort of confirms 
what I think is possible, that this warming and cooling is a sinusoidal 
wave and that in fact, let me just read what Dr. North says in his 
testimony.  He says that it is plausible that the Northern Hemisphere 
was warmer during the last few decades of the 20th Century than during 
any comparable period over the preceding millennium.  That is what he 
says.  However, the substantial uncertainties currently present in 
the quantitative assessment, same thing that Dr. Wegman says, of 
large-scale surface temperature changes prior to about 1600 A.D. 
lower our confidence in this conclusion compared to the high level 
of confidence we place in the Little Ice Age cooling and 20th Century 
warming.  So we have two distinguished individuals who are 
professionals in their fields indicating that it is not absolutely 
true that Dr. Mann is correct in his analysis and Dr. North went on 
to say even less confidence can be placed in the original conclusions
 by Dr. Mann.
	So, I mean, for anybody on the other side to say this not a 
legitimate hearing is incorrect.  We have taken people that Dr. Mann 
wanted and we put them on here as witnesses.  We have asked Dr. Mann 
to come to this hearing.  We have asked him to come to the 27th.  He 
won't come. He has hired a lawyer to spar with our people to say why 
he won't come.  By golly, if he really is interested in solving this 
problem, I would cut my vacation short and whatever he is doing to say 
I will be here because I think in the interest of science, I would 
like to have an open hearing and talk about it.  So I think, one, it 
is a legitimate hearing.  Two, we have offered Dr. Mann two 
opportunities and yet his lawyer has indicated he won't show up.  So 
this is a very important issue but I think overall, all of us here 
are trying to understand this and we would agree that there is 
probably global warming.  What we want to know is, is this sinusoidal 
or is this something that is aberrational.
	Let me conclude by saying that yes, we should have further 
inquiries into this matter.  Perhaps as a result of this hearing we 
will.  Temperature studies and the effect of climate change, all these
 are very important to our very existence.  So Mr. Chairman, I commend 
what you are doing and I commend the other side too to keep an open 
mind here and to hear Dr. Wegman and to hear Dr. North and to read 
their opening statements where you will see they have less confidence 
and they certainly have as much credibility on this matter as 
Dr. Mann, and I am just so sorry, so sorry that Dr. Mann is not 
showing up today, he is not showing up on the 27th, and at this 
point I am not clear, Mr. Chairman, when you will get him.  Thank 
you. 
	MR. WHITFIELD.  Ms. Baldwin, you are recognized for 5 minutes.
	MR. STUPAK.  Mr. Chairman, may I ask unanimous consent that 
the letter that we received from Dr. Mann's lawyer indicating he would 
like to come at the same time these witnesses are here be entered into 
the record.
	MR. WHITFIELD.  It has been.
	MR. STUPAK.  Oh, it has been?  Oh, okay.  Thank you.
	MR. WHITFIELD.  We have had two letters introduced into the 
record from his lawyer, both.
	MS. BALDWIN.  Thank you, Mr. Chairman.  It doesn't take much 
more than a quick walk outside today to know that the thermometer has 
reached dangerously high levels and government heat alerts are 
abounding these days but this summer is not unique.  Each year 
summers are growing warmer and warmer and so are the winters, falls,
 and springs.  Of the 20 hottest years on record, 19 have occurred in 
the 1980s or later.  2005 was one of the hottest years on records and 
so far 2006 has set record levels for its high temperatures.
	Unfortunately, despite overwhelming scientific evidence that
 our planet is warming at dramatic rates, no political consensus for 
bold action has followed and that is the problem.  Politicians ignore 
sound science showing evidence that the Earth is warming at an 
unprecedented rate, that carbon dioxide levels are rising, and that 
human activities are largely the cause.  But beyond ignoring sound 
science, they are doing other disturbing things.  I see political 
interference in science these days.  In fact, time after time, sound 
science has been censored in order to maintain a political agenda.  
Here are just a few examples.
	In 2003, the EPA was ordered by the White House to delete 
critical sections relating to climate change from its report on the
 environment.  In 2005, the White House insisted upon weakening 
language relating to the impact of global climate change in a 
document that served as the basis of negotiations during the G8 
Summit, and just a few months ago the Administration tried to silence 
a NASA scientist from talking about the need to reduce greenhouse 
gases linked to global warming.  I could point to many other examples, 
some on this topic, some outside, but it is a disturbing trend indeed.
	With all these examples, it only becomes more clear that false 
logic will not bring us closer to an understanding of the scientific 
truth.  The truth is alarming.  Sea levels are rising.  Glaciers are 
melting and storms are becoming more intense, and the result is the 
near extinction of animals such as polar bears, the compromising of 
coastal ecosystems, and the threatening of human life as heat waves 
become prevalent and disease-carrying insects grow more abundant.
	Mr. Chairman, I often speak about America's need to take bold 
action and the importance of us leading the world on environmental 
issues.  Now is the time for us to show our commitment for if we do 
nothing, we risk an uncertain and unstable future.  So I ask, what 
are the consequences if the cynics and naysayers and keepers of the 
status quo are wrong?  We have a moral and an ethical obligation to 
act and I just hope that today we will take some steps in that right
 direction.
	Thank you, Mr. Chairman.  I yield back the balance of my time.
	MR. WHITFIELD.  Thank you, Ms. Baldwin.  At this time I 
recognize Mrs. Blackburn.
	MRS. BLACKBURN.  Thank you, Mr. Chairman.  Thank you for 
holding the hearing.  Thank you to the staff for the preparation work 
they have done and to our witnesses appearing before us to comment 
on the matter.  We thank you for being here.  We are concerned about 
it.  I do think it is prudent to address the issue and we are seeking
 information.  We thank you for being here to supply some.
	The ability to obtain and analyze the data and the methods 
that a scientist uses to form a theory about the universe is central
 to science.  For hundreds of years society has placed the utmost 
importance on the scientific method to validate theories which is 
predicated on the ability to replicate and verify a scientist's work. 
If the work cannot be replicated and verified by independent experts, 
then that work's conclusions become more speculation and possibly 
some will say it should be open to classification as outright 
scientific dishonesty.
	Last year Chairman Barton inquired into the background of 
some recent climate change studies that had been held by scientific 
portions of the scientific community as proof of drastic global 
warming.  Now, I am old enough to remember that as a teen in the 
late 1960s, I sat in science classes and in a geology class and I 
was warned of a returning and impending ice age.  By the time I 
reached my current age, the world was going to be covered in ice, 
North America would have a 9-month winter, our food supplies would 
be short, and I would be freezing to death all the time.  Well, I 
guess times changed or maybe that old group of scientists had some 
kind of political interference in favor of the new group of 
scientists who now want the Earth to warm up.
	Now, after some independent analysis it seems that all 
scientists could possibly be misled on some of their issues.  Both 
the National Academy of Sciences and Dr. Wegman's committee analyzed 
the hockey stick report by Dr. Mann that has become the poster child 
for proof of global warming.  The committees came to the conclusion 
that Dr. Mann's hockey stick report failed verification tests and did 
not employ proper statistical methods.  Also, it appears that Dr. Mann 
is part of a social network or could be part of a social network of 
climate scientists who almost always use the same data sets and review 
each other's works.  There is a contention that they would dismiss 
critics who had legitimate concerns, rarely used statistical experts 
for the data they used in their reports, and make it very difficult 
for reviewers to obtain background data and analysis.  These 
revelations point to the lack of independent peer review and how it 
is practically impossible to replicate or verify Dr. Mann's work by 
those not affiliated with the network of scientists, so we are looking 
forward to hearing about that work today.  Could it be that this 
particular work violates the principles of the scientific method 
and should be dismissed until it meets the basic qualifications?  
Could that have been some of what happened to the Ice Age return 
theory of the 1960s?
	Climate is affected by numerous causes that interact with 
each other.  When a scientific paper comes to a conclusion about 
climate, its results must be able to be replicated and shown to 
have direct causation and not merely correlation.  If these steps 
cannot be done, then making conclusive statements of how one cause
 changes the climate is unwarranted and not real science.
	Now, there is strong evidence that the Earth has warmed
 about half a degree Fahrenheit from 1900 to 1940 but this is 
widely attributed to an increase in solar activity during those 
years and there are indications that the Earth warmed another 
half degree Fahrenheit from 1940 until the present but that much of 
this warming occurred in the past 7 years, and if you look at the 
surface record in the satellite data, it is pretty clear and 
possible that this warming is mostly due to the 1998 El Nino, so 
for the past hundred years the Earth has warmed about one degree 
and you can make the cause that it was not caused by human activity 
but by natural events.  Possibly that is what happened to the return 
of that old Ice Age.
	Mr. Chairman, if one looks at the data in an objective 
manner, I believe that one would conclude that the Earth's climate 
is not in serious danger or not standing at the edge of a precipice.
  Maybe our focus should be first on getting the information.  Maybe 
our focus should not be on environmentalism.  Maybe the focus should
 be on common-sense conservatism.  I would challenge my colleagues 
on the other side to approach this issue to learn the truth about 
the Earth's climate, not to form an agenda.
	I am looking forward to our witnesses in the hearing today.  
I yield back.
	MR. WHITFIELD.  Thank you, Mrs. Blackburn.  I think that 
concludes the opening statements so we will proceed to the first 
panel of witnesses, and I would say to you, Dr. North and Dr. Wegman,
 that this committee is holding an investigative hearing, and when 
doing so we do have the practice of taking testimony under oath, 
and I would ask you, do either of you have any objection to 
testifying under oath?  
Now, Dr. Wegman, accompanying you today is one of the statisticians 
that worked with your three-person panel, and would you introduce 
her?  Although it is my understanding she is not going to be 
testifying but she is from Johns Hopkins, I believe.
	DR. WEGMAN.  That is correct.  It is Dr. Yasmin Said.  
Dr. Said actually did a tour at Johns Hopkins but has just won a 
very prestigious National Institutes of Health postdoctoral 
fellowship and she will be with us in George Mason for the next 
3 years.
	MR. WHITFIELD.  And although she is not going to testify, 
you may consult with her.  Dr. Wegman, if you and Dr. North would 
stand up, I would like to swear you in.  Of course, under the rules 
of the House and the rules of the committee, you are also entitled 
to legal counsel and I am assuming you don't need legal counsel 
today, but if you do--
	DR. WEGMAN.  Hopefully not.
	MR. WHITFIELD.  If you would raise your right hand.
	[Witnesses sworn.]
	MR. WHITFIELD.  Thank you, very much.  You are now both under 
oath, and Dr. Wegman, you are recognized for your opening statement, 
and I would say to both of you, I know both of you have rather 
lengthy documents that we appreciate your preparing and those will 
be entered into the record in their entirety, and if you all could 
keep your statements to 5 to 7 minutes or so, we would appreciate 
that.  Dr. Wegman, you are recognized.

STATEMENTS OF DR. EDWARD J. WEGMAN, CENTER FOR COMPUTATIONAL 
STATISTICS, GEORGE MASON UNIVERSITY; AND DR. GERALD R. NORTH, 
DEPARTMENT OF ATMOSPHERIC SCIENCES, TEXAS A&M UNIVERSITY

	DR. WEGMAN.  Thank you, sir.  I would like to begin by 
circumscribing the substance of our report.  We were asked to
 provide independent verification by statisticians of the critiques 
of the statistical methodology found in the papers of Drs. Michael 
Mann, Raymond Bradley, and Malcolm Hughes published respectively in 
Nature in 1998 and in Geophysical Research Letters in 1999.  These 
two papers have commonly been referred to as MBH98 and MBH99.  The 
critiques have been made by Stephen McIntyre and Ross McKitrick 
published in Energy and Environment in 2003 and again in Energy and
 Environment and in Geophysical Research Letters in 2005.  We refer 
to these are MM02, 05a and 05b, respectively.
	We were also asked about the implications of our assessment. 
 We were not asked to assess the reality of global warming and indeed 
this is not an area of our expertise.  We do not assume any position 
with respect to global warming except to note in our report that the
 instrumented record of global average temperature has risen since 
1850 according to the MBH99 chart by about 1.2 degrees Centigrade, 
and in the NAS panel report chaired by Dr. North, about six-tenths 
of a degree Centigrade in several places in that report.
	Our panel is composed of myself, Edward Wegman at George 
Mason University, David W. Scott at Rice University, and as 
mentioned, Yasmin Said at the Johns Hopkins University.  This ad
 hoc panel has worked on a pro bono basis.  We have received no 
compensation, not even taxi fare, and no financial interest and 
we have no financial interest in this.
	Can we see slide one, please?  In figure 1, we have a 
document, a chart that came out of Dr. Bradley's book on 
paleoclimatology, and sort of indicates the kind of things that
 are used as proxy data in paleoclimatology.  One thing I would 
like to point out in particular that is important I think for 
understanding this area is the things that are indicated--if you 
look--
	MR. WHITFIELD.  Dr. Wegman, we need for you to use your mic.  
I know it is going to be difficult but we could not hear you when 
you turned around there.
	DR. WEGMAN.  I will refrain from doing that.  The point of 
this graphic is that there are many factors that affect all of the 
proxies that are used in paleoclimate temperature reconstruction, 
and without carefully teasing out those effects, the tree rings, 
the ice cores, and so on, are not by, in and of themselves totally 
temperature records.
	So MBH98 and 99 use several proxy indicators to measure 
global climate change.  Primarily these include historical records, 
tree rings, ice cores, and coral reefs.  More details of the proxies 
are given in our report and mentioned in the written testimony.
	Could we go to figure 2, please?  Some examples of tree ring 
proxy series are given in figure 2.  Most of the proxy series for 
these tree rings show little structure but the last two show the
 characteristic hockey stick shape.  The principal component-like 
methodology in MBH98 and 99 preferentially emphasizes these shapes as 
we shall see.  Principal component analysis methodology is at the
 core of the MBH98 and 99 analysis methodology.  Principal component
 analysis is a statistical methodology often used for reducing data 
sets with many variables into data sets with fewer but composite 
variables.  The time series proxy data involved are transformed 
into their principal components where the first principal component 
is intended to explain most of the variation present in the data 
variables.  Each of the subsequent principal components explains 
less and less of the variation.  In the methodology of MBH98 and 
99, the first principal component is used in the temperature 
reconstruction.
	Could we have figure 3, please?  The two principal methods 
for temperature reconstructions have been used. CFR, climate field
 construction is used in MBH98/99 although that terminology was 
not used formally until 2005, I believe, and the other is CPS, 
climate-plus-scale methodology.  The CFR is essentially the 
principal component-based analysis and the CPS is a simple 
averaging of climate proxies.  The controversy of the MBH98/99
 method lies in that the proxies are incorrectly centered on the 
mean period of 1902 to 1995, rather than on the whole time period.
  The proxy data exhibiting the hockey stick are actually 
decentered low.  The updated MBH98/99 reconstruction is given in 
figure 3.  This fact that the proxies are centered low is apparent 
in figure 3 because for most of the thousand years the 
reconstruction is below zero.  This is temperature anomaly. Because 
the hockey stick proxies are centered too low, they will exhibit a 
large effective variance, allowing the method to exhibit a 
preference for selecting them as the first principal component. 
The net effect of decentering the proxy data in MBH98 and MBH99 
is to produce the hockey stick shape.  Centering on the overall 
mean is a critical factor in using principal component methodology
 properly.
	Could we have figure 4, please?  To illustrate this, we 
consider the North American tree series and apply the MBH98 
methodology.  The top panel shows the result from decentering.  The 
bottom panel shows the result when the principal components are 
properly centered.  The centering does make a significant 
difference in the reconstruction, and as you see, while the top
 panel illustrates the temperature rise or purported temperature 
rise in the last 100 years or so, the bottom panel when properly 
centered does not have this temperature rise.
	Could we go to figure 5?  To further illustrate this, we 
digitized the temperature profile published in the IPCC 1990 report 
and we did apply both the CFR and the CPS methods to them.  The data 
used here are 69 unstructured noise pseudo-proxy series with only 
one copy of the 1990 profile.  The upper left panel illustrates the 
PC1 with proper centering.  In other words, no structure is shown.  
The other three panels indicate what happens when using principal 
components with an increasing amount of decentering.  Again, the 
single series begins to overwhelm the 69 other pure noise series. 
Cleary, this decentering has a big effect.
	It is not clear that Dr. Mann and his associates realized 
the error in their methodology at the time of publication but our 
re-creation supports the critique of the MBH99 methods.
	As commentary, in general we found the writing in MBH98 and 
99 to be somewhat obscure and incomplete and the criticisms by 
MM03/05a and 05b to be valid.  The reasons for setting 1902-1995 as 
the calibration period presented in the narrative of MBH98 sounds 
plausible on the surface and the error may be easily overlooked by 
someone not trained in statistical methodology.  We note that there 
is no evidence that Dr. Mann or any of the other authors in the 
paleoclimate studies have significant interactions with mainstream
 statisticians.
	Because of this apparent isolation, we decided to attempt 
to understand the paleoclimate community by exploring the social 
network of authorships in the temperature reconstruction area.  We 
found that at least 43 authors have direct ties to Dr. Mann--and 
this should be figure 6, please; thank you--have direct ties to 
Dr. Mann by virtue of coauthored papers with him.  Our findings 
from this analysis suggest that authors in this area of the 
relatively narrow field of paleoclimate studies are closely 
connected.  Dr. Mann has an unusually large reach in terms of 
influence.  He is the coauthor with every one of these people 
which are indicated by the black edge borders on the top and the 
side of this graph.  In particular, he has a close connection with 
Drs. Jones, Bradley, Hughes, Briffa, Rutherford, and Osborne and 
those are indicated by the solid block on the upper left-hand 
corner.
	This area of social networks is based off a graph theoretic
 representation, and if we go to figure 7, we can see the graph 
theoretic representation.  Because of these close connections, 
independent studies may not be as independent as they appear to be
 on the surface.  Although we have no direct data on the functioning
 of peer review within the paleoclimate community but, with me having 
35 years of experience with peer review in both journals as well as 
evaluation of research proposals, peer review may not have been as 
independent as would generally be desirable.
	Could we have figure 8, please?  Figure 8 is a graphic that 
depicts a number of papers in the paleoclimate reconstruction area 
together with some of the proxies used.  We note that many of the 
proxies are shared.  Some of the same data also suggests a lack of
 independence.  
The MBH98/99 work has been sufficiently politicized that this 
committee can hardly reassess their public positions without losing
 credibility.  Overall, our community believes that the MBH98/99 
assessment that the decade of the 1990s was likely the hottest 
decade in the millennium and that 1998 was likely the hottest year 
in the millennium cannot be supported by their analysis because of 
the mathematical flaws.
	We have some recommendations which flowed out of our 
analysis. Recommendation one:  Especially when massive amounts of 
public monies and human lives are at stake, academic work should 
have a more intense level of scrutiny and review.  It is especially 
the case that authors of policy-related documents like the IPCC
 report should not be the same people as those that constructed 
the academic papers.
	We believe that federally funded research agencies should 
develop a more comprehensive and concise policy on disclosure.  
All of us writing this report have been federally funded.  Our 
experience with Federal funding agencies has been that they do 
not generally articulate clear guidelines to the investigators as
 to what must be disclosed.  Federally funded work, including code, 
should be made available to other researchers upon reasonable 
request, especially if the intellectual property has no commercial 
value.  Some consideration should be granted to the data collectors 
to have exclusive use of their data for 1 or 2 years prior to 
publication but data collected under Federal support should be made 
publicly available.
	Recommendation three:  With clinical trials for drugs and 
devices to be approved for human use by the FDA, review and 
consultation with statisticians is expected.  Indeed, it is standard 
practice to include statisticians in the application for approval 
process.  We judge this to be a good policy when public health and 
also when substantial amounts of monies are involved--for example, 
when there are major policy decisions to be made based on statistical
 assessments.  In such cases, evaluation by statisticians should be 
standard practice.  The evaluation phase should be a mandatory part 
of all grant applications and funded accordingly.
	Finally, recommendation four; emphasis should be placed on 
the Federal funding of research related to a fundamental understanding 
of the mechanisms of climate change.  Funding should focus on
 interdisciplinary teams and avoid narrowly focused disciple 
research.  That is a general comment and by interdisciplinary 
teams, I mean including teams that involve what I like to call the
 enabling sciences such as mathematics, computer science, and 
statistics.  Thank you, sir.
	[The prepared statement of Dr. Edward J. Wegman follows:]

PREPARED STATEMENT OF DR. EDWARD J. WEGMAN, CENTER FOR COMPUTATIONAL
 STATISTICS, GEORGE MASON UNIVERSITY

I would like to begin by circumscribing the substance of our report. 
We were asked to provide an independent verification by statisticians 
of the critiques of the statistical methodology found in the papers 
of Drs. Michael Mann, Raymond Bradley and Malcolm Hughes published
 respectively in Nature in 1998 and in Geophysical Research Letters 
in 1999. These two papers have commonly been referred to as MBH98 and 
MBH99. The critiques have been made by Stephen McIntyre and Ross 
McKitrick published in Energy and Environment in 2003 and in Energy 
and Environment and in Geophysical Research Letters in 2005. We refer
 to these as MM03, MM05a, and MM05b respectively. We were also asked 
about the implications of our assessment. We were not asked to assess 
the reality of global warming and indeed this is not an area of our 
expertise. We do not assume any position with respect to global 
warming except to note in our report that the instrumented record of 
global average temperature has risen since 1850 according to the MBH 
99 chart by about 1.2� centigrade. In the NAS panel Report chaired by 
Dr. North, .6� centigrade is mentioned in several places. 
Our panel is composed of Edward J. Wegman (George Mason University), 
David W. Scott (Rice University), and Yasmin H. Said (The Johns 
Hopkins University). This Ad Hoc Panel has worked pro bono, has 
received no compensation, and has no financial interest in the 
outcome of the report. 


MBH98, MBH99 use several proxy indicators to measure global climate 
change. Primarily, these include historical records, tree rings, ice 
cores, and coral reefs. More details of proxies are given in the 
report and mentioned in the written testimony. [The width and density 
of tree rings vary with climatic conditions (sunlight, precipitation,
 temperature, humidity, and carbon dioxide and nitrogen oxides 
availability), soil conditions, tree species, tree age, and stored
 carbohydrates in the trees. The width and density of tree rings are 
dependent on many confounding factors, making isolation of the 
climatic temperature signal uncertain. It is usually the case that 
width and density of tree rings are monitored in conjunction in order 
to more accurately use them as climate proxies. Ice cores are the 
accumulation of snow and ice over many years that have recrystallized 
and have trapped air bubbles from previous time periods. The 
composition of these ice cores, especially the presence of hydrogen 
and oxygen isotopes, provides a picture of the climate at the time. 
The relative concentrations of the heavier isotopes in the condensate 
indicate the temperature of condensation, allowing for ice cores to be 
used in global temperature reconstruction. In addition to the isotope
 concentration, the air bubbles trapped in the ice cores allow for 
measurement of the atmospheric concentrations of trace gases, 
including greenhouse gases carbon dioxide, methane, and nitrous
 oxide.]
 

Some examples of tree ring proxy series are given in Figure 2. Most of 
the proxy series show little structure, but the last two show the
 characteristic 'hockey stick' shape. The principal component-like 
methodology in MBH 98/99 preferentially emphasizes these shapes as 
we shall see.
Principal component analysis methodology is at the core of the 
MBH98/99 analysis methodology. Principal component analysis is a 
statistical methodology often used for reducing datasets with many 
variables into datasets with fewer, but composite variables. The 
time series proxy data involved are transformed into their principal
 components, where the first principal component is intended to 
explain most of the variation present in the data variables. Each 
subsequent principal component explains less and less of the 
variation. In the methodology of MBH98/99, the first principal
 component is used in the temperature reconstruction.



Two principal methods for temperature reconstructions have been used; 
CFR (climate field construction used in MBH98/99) and CPS (climate-
plus-scale). The CFR is essentially the principal component based 
analysis and the CPS is a simple averaging of climate proxies. The 
controversy of the MBH98/99 methods lies in that the proxies are 
incorrectly centered on the mean of the period 1902-1995, rather 
than on the whole time period. The proxy data exhibiting the hockey 
stick shape are actually decentered low. The updated MBH99 
reconstruction is given in Figure 3. This fact that the proxies are 
centered low is apparent in Figure 3 because for most of the 1000 
years, the reconstruction is below zero. Because the 'hockey stick' 
proxies are centered too low, they will exhibit a larger effective 
'variance', allowing the method to exhibit a preference for 
selecting them as the first principal component. The net effect of 
this decentering using the proxy data in MBH98 and MBH99 is to 
produce a 'hockey stick' shape. Centering on the overall mean is a
 critical factor in using the principal component methodology
 properly. 

 

To illustrate this, we consider the North America Tree series and 
apply the MBH98 methodology. The top panel shows the result from the 
de-centering. The bottom panel shows the result when the principal 
components are properly centered. Thus the centering does make a 
significant difference to the reconstruction. 


To further illustrate this, we digitized the temperature profile 
published in the IPCC 1990 report and applied both the CFR and the 
CPS methods to them. The data used here are 69 unstructured noise 
pseudo-proxy series and only one copy of the 1990 profile. The upper 
left panel illustrates the PC1 with proper centering. In other words, 
no structure is shown. The other 3 panels indicate what happens using
 principal components with an increasing amount of de-centering. 
Again, the single series begins to overwhelm the other 69 pure noise 
series. Clearly, these have a big effect.    
It is not clear that Mann and associates realized the error in their
 methodology at the time of publication. Our re-creation supports the 
critique of the MBH98 methods.
In general, we found the writing in MBH98 and MBH99 to be somewhat 
obscure and incomplete and the criticisms by MM03/05a/05b to be valid. 
The reasons for setting 1902-1995 as the calibration period presented 
in the narrative of MBH98 sounds plausible, and the error may be easily
 overlooked by someone not trained in statistical methodology. We note 
that there is no evidence that Dr. Mann or any of the other authors in
 paleoclimate studies have had significant interactions with 
mainstream statisticians.
Because of this apparent isolation, we decided to attempt to 
understand the paleoclimate community by exploring the social 
network of authorships in temperature reconstruction. 


We found that at least 43 authors have direct ties to Dr. Mann by 
virtue of coauthored papers with him. Our findings from this analysis 
suggest that authors in the area of this relatively narrow field of
 paleoclimate studies are closely connected. Dr. Mann has an 
unusually large reach in terms of influence and in particular 
Drs. Jones, Bradley, Hughes, Briffa, Rutherford and Osborn.


Because of these close connections, independent studies may not be 
as independent as they might appear on the surface. Although we have 
no direct data on the functioning of peer review within the 
paleoclimate community, but with 35 years of experience with peer 
review in both journals as well as evaluation of research proposals, 
peer review may not have been as independent as would generally be 
desirable.


Figure 8 is a graphic that depicts a number of papers in the 
paleoclimate reconstruction area together with some of the proxies 
used. We note that many of the proxies are shared. Using the same 
data also suggests a lack of independence. 
The MBH98/99 work has been sufficiently politicized that this 
community can hardly reassess their public positions without losing
 credibility. Overall, our committee believes that the MBH99 
assessment that the decade of the 1990s was the likely the hottest 
decade of the millennium and that 1998 was likely the hottest year 
of the millennium cannot be supported by their analysis. 

Recommendations
Recommendation 1. Especially when massive amounts of public monies
 and human lives are at stake, academic work should have a more 
intense level of scrutiny and review. It is especially the case 
that authors of policy-related documents like the IPCC report, 
Climate Change 2001: The Scientific Basis, should not be the same 
people as those that constructed the academic papers. 
Recommendation 2. We believe that federally funded research agencies 
should develop a more comprehensive and concise policy on 
disclosure. All of us writing this report have been federally
 funded. Our experience with funding agencies has been that they do 
not in general articulate clear guidelines to the investigators as 
to what must be disclosed. Federally funded work including code 
should be made available to other researchers upon reasonable 
request, especially if the intellectual property has no commercial 
value. Some consideration should be granted to data collectors to 
have exclusive use of their data for one or two years, prior to 
publication. But data collected under federal support should be 
made publicly available. 
Recommendation 3. With clinical trials for drugs and devices to be 
approved for human use by the FDA, review and consultation with 
statisticians is expected. Indeed, it is standard practice to 
include statisticians in the application-for-approval process. We 
judge this to be a good policy when public health and also when 
substantial amounts of monies are involved, for example, when there 
are major policy decisions to be made based on statistical 
assessments. In such cases, evaluation by statisticians should be 
standard practice. This evaluation phase should be a mandatory 
part of all grant applications and funded accordingly.
Recommendation 4. Emphasis should be placed on the Federal funding
 of research related to fundamental understanding of the mechanisms 
of climate change. Funding should focus on interdisciplinary teams 
and avoid narrowly focused discipline research.

	MR. WHITFIELD.  Thank you, Dr. Wegman, and Dr. North, you 
are recognized for your opening statement.
	DR. NORTH.  Thank you, Mr. Chairman.  Before I begin, I would 
like to introduce Peter Bloomfield from North Carolina State 
University, who is a professor of statistics there, and he was on 
our committee, the NAS committee, and so I will use him if I need to 
during the course of--
	MR. WHITFIELD.  Welcome, Dr. Bloomfield.
	DR. NORTH.  Good morning, Mr. Chairman, and members of the
 committee.  My name is Jerry North.  I am a professor of atmospheric 
sciences at Texas A&M University and it is nice to see one Aggie here.
  He said he took some statistics there and I suspect he knows more 
than he is letting on today.  And I served as the Chairman of the 
National Research Council's committee on surface temperature 
reconstruction for the last 2,000 years.
	My comments today will highlight the findings of our 
committee's recently released report.  Its aim was to asses the 
state of scientific efforts to reconstruct surface temperature 
records for the Earth over the last few thousand years, and to 
comment on the implications of these efforts for our understanding 
of global climate change.  Surface temperature reconstructions are 
only one of many lines of evidence supporting the conclusion that 
the climate is warming in response to human activities.  These long 
records give context and perspective to the issue but they are not 
the primary evidence.  In fact, human-induced climate change is 
quite real.
	First some background.  Widespread thermometer records only 
the last 150 years or so.  To extrapolate deeper into the past, 
scientists have learned to use proxy evidence such as tree rings, 
corals, ocean and lake sediments, ice cores, glacier records, 
boreholes, and historical documents.  To give one example, the 
advances and retreats of glaciers can tell us whether the climate 
has been warmer or cooler on the average at that location.  Starting 
in the 1990s, scientists began combining proxy evidence for many 
locations in an effort to estimate temperature changes averaged 
over broad geographic regions for the last few thousand years.
	Much attention has been concentrated on papers published by 
Michael Mann, Raymond Bradley, and Malcolm Hughes in 1998 and 1999. 
This is partly because the authors concluded that the Northern 
Hemisphere was warmer during the late 20th Century than at any time 
during the past millennium.  In addition, it was illustrated with a 
simple graphic, the so-called hockey stick curve, that was featured
 prominently in the 2001 Intergovernmental Panel on Climate Change 
report, and you have seen that graphic.
	Our committee examined the scientific literature in great 
depth, considered written and oral remarks from experts representing 
a broad range of perspectives.  We reached five major conclusions.  
Number one, the warming of about one degree Fahrenheit during the 
20th Century is real.  No one doubts it.
	Number two:  Besides the rapid warming in the 20th Century, 
two other features appear to be common in the records, a cool period 
centered in A.D. 1700 called the Little Ice Age and a warm period 
around 1000 known as the Medieval Warm Period, details about the 
latter being much less certain.
	Number three:  It can be said with a high level of 
confidence that global mean surface temperature was higher during 
the last few decades of the 20th Century than during any comparable 
period since 1600.  This statement is justified by the consistency 
of the evidence from a wide variety of geographically diverse 
proxies.  If we could put that graphic up.  That one.  That is 
the only one I will show.  So here is the kind of diverse evidence 
that I would like to just mention.  These are different curves from 
different investigators.  Most of them have come out after the Mann 
et al. work, and some of them don't rely on the statistical 
techniques at all.  The boreholes, for example, come from the 
direct physics, no calibration with the instrumental temperatures, 
and the same is true for the glacier length records.
	Number four:  Less confidence can be placed in large-scale 
surface temperature reconstructions from A.D. 900 to 1600.  We find 
that temperatures at many, but not all, locations were higher during 
the last 25 years than during any period of comparable length since 
A.D. 900, but the uncertainties increase substantially as one moves 
backward in time through this period and are not yet fully 
quantified.  Now, the way we tried to illustrate that on this 
graphic is by showing a sort of darkening graying as you go back, 
and one of my colleagues on the committee says well, as you go back 
beyond the year 1600, things get a little murkier, so the amount of 
the kinds of data that we have and so on are much less certain.  We 
don't understand all of the interrelations and so forth, so I can go 
into that in more detail if you need it.
	And number five, very little confidence can be assigned to 
statements concerning the average surface temperatures prior to about 
A.D. 900, so we just don't know enough about that period.
	Now, the basic conclusion of the 1999 paper by Mann and his 
colleagues was that the late 20th Century warmth in the Northern 
Hemisphere was unprecedented during at least the last 1,000 years. 
This conclusion has substantially been supported by an array of 
evidence, but substantial uncertainties remain for the period before 
about 1600, and I can give you some illustrations of other ways of 
looking at the problem later if that should come up in questions.  
Our main disagreements with the Mann 98/99 papers are related to 
the assertions about warmth of individual decades and individual 
years.  We don't subscribe to that kind of definition of the 
problem.  We also question some of their statistical methodology, 
in fact, some of the same claims that were put forward by 
Dr. Wegman and you will hear some later as well.
	However, our reservations with some aspects of the original
 papers by Mann and colleagues should not undermine the fact that 
the climate is warming and will continue to warm as a result of 
human activities.  In fact, the scientific consensus regarding 
human-induced climate warming, global warming, would not be 
substantively altered if the global mean surface temperature 
1,000 years ago was found to be as warm as it is today although 
there is evidence that this really is a very exceptional period 
that we are in now, and again, I can come back to that during 
questions.  This is because we don't know enough about the driving 
forces of the climate over that long period.
	During the last 150 years, we have considerable evidence 
about the increase in greenhouse gas concentrations and we know a 
lot about the other things that tend to nudge the climate system 
as well.  By the way, a lot has been learned about climate in the 
last 30 or 40 years.  I mean, it is a very rapidly changing field 
and we have all the giant computers and satellites now at our 
disposal to help us.  So we know a lot more about this than we 
did 30 years ago.  And in the last quarter century, when warming 
was particularly steep, we also have good data on the sun because 
for the last 25 years we have been measuring the sun very, very 
accurately from outside the atmosphere using satellites.  
Aerosols--we have a very good idea of how the dust and tiny 
particles in the atmosphere have been changing over the last 
25 years and probably 50, both of which--both of these two 
drivers of climate change, the sun and the aerosols, really are
 negligible compared to the forcing from greenhouse gases.
	Moreover, climate models can only reproduce the warming of 
the 20th Century when greenhouse gases are included.  Our knowledge 
of the driving forces over the last several thousands of years is 
not yet good enough to go back beyond this recent period, so that 
is the reason that that early data doesn't really close or finish 
off the story.
	So now in conclusion, our committee finds that large-scale 
surface temperature reconstructions contribute to climate research, 
they are important, and that they contain meaningful climate 
signals.  Our confidence in the reconstructions becomes stronger 
when multiple independent lines of evidence point to the same 
general result such as the warmth of the last few decades of the 
20th Century relative to the last 400 years.  Further research, 
especially in the collection of additional proxy evidence, would 
help to reduce the uncertainties and allow us to make more 
definitive conclusions over longer time periods.
	I thank you for your attention, and I would be happy to 
answer any questions, and I may call on Dr. Bloomfield to help me.
	[The prepared statement of Dr. Gerald R. North follows:]


PREPARED STATEMENT OF DR. GERALD R. NORTH, DEPARTMENT OF ATMOSPHERIC 
SCIENCES, TEXAS A&M UNIVERSITY




	MR. WHITFIELD.  Dr. North, thank you and Dr. Wegman both 
for your testimony, and Dr. North, now, you are a Ph.D.  Are you 
a climatologist or--
	DR. NORTH.  I have a Ph.D. in physics from the University 
of Wisconsin.
	MR. WHITFIELD.  From the University of Wisconsin.
	DR. NORTH.  Yes.
	MR. WHITFIELD.  A wonderful school.
	DR. NORTH.  Yes.  It is a wonderful school.
	MR. WHITFIELD.  Almost as good as Texas A&M.
	DR. NORTH.  Well, comparable.
	MR. WHITFIELD.  Now, have you had the opportunity to review 
Dr. Wegman's and his associates--
	DR. NORTH.  Yes, I did receive it a few days ago so I don't 
think I have read it in the detail that I should but I have been able 
to look through it.
	MR. WHITFIELD.  And you all don't know each other?  You are 
not friends or--
	DR. NORTH.  No, I met him at our briefing a couple of weeks 
ago just for a handshake.
	MR. WHITFIELD.  Well, I was wondering if you might just take 
a minute or two to summarize your--as a professional in this area 
and your experience in this area.  What is your reaction to their 
report?
	DR. NORTH.  Well, I think that on many things we are in 
agreement.  The studies that--I mean, the examination they did of 
the statistical procedures and the Mann et al. papers is not the 
way we would--that I would have done it in hindsight, especially 
now looking back.  It is not the way I would have done it.  I don't 
think there is anything dishonest about it or anything like that, 
but I think that the analyses that the Wegman group did really 
were--some of those were examined by the statisticians on our 
committee and I don't think that we are in any great disagreement 
about it.  Let me just mention this, that the criticisms don't mean 
that the MBH claims were wrong.  They just mean that the MBH claims 
are not convincing by themselves.  So if you pull together other 
information, then that does change the view a bit.
	MR. WHITFIELD.  Now, Dr. Wegman, I am not a statistician 
but obviously a statistician is where you look at data and from 
that data you try to look at the probability of something happening 
or not happening and whatever.  Is that just in a rough layman's 
term what statistics is all about, or give me your definition of 
statistics or a statistician.
	DR. WEGMAN.  Well, I think a statistician generally tries 
to look at data and represent the meaning, the inferences that are 
available from that data as straightforwardly and honestly as 
possible.
	MR. WHITFIELD.  Now, Dr. North said that his group had 
reviewed your document and that they agreed with much of what you 
said and you have indicated that one of your primary concerns about 
the Mann document is the center point that was utilized in his 
hockey stick graph.  Would you elaborate on that a little bit?
	DR. WEGMAN.  Yes.  They used the period from 1902 to 1995, 
which was the instrumented temperature record that they used, so 
they used that period to calibrate the proxy data.  They centered 
their overall proxy data on that period, 1902 to 1995, and of 
course temperature was rising in that period, so when you center 
on that period, you push the rest of the proxy data below the 
axis.  That has, as I mentioned, the net effect of increasing the 
variance and making the principal component methodology pick out 
that kind of shape.  So it preferentially attempts to fit those 
kind of shapes in the first principal component.
	MR. WHITFIELD.  And it does establish this hockey stick 
showing a rapidly increasing--
	DR. WEGMAN.  That is essentially the mechanism that creates 
the hockey stick.  If you do the--as I showed in the one graph, if 
you do the centering properly, the hockey stick disappears.
	MR. WHITFIELD.  Now--
	CHAIRMAN BARTON.  Would the Chairman yield on that point?
	MR. WHITFIELD.  Yes.
	CHAIRMAN BARTON.  Dr. Wegman, you say when you center it 
properly.  Put in layman's terms that those of us that are not 
statisticians, what does that mean, centering it properly?
	DR. WEGMAN.  Thank you for asking.  The principal components 
analysis methodology requires that the data be centered on the mean 
of the overall series, so if you are doing reconstructions, let us 
say, back to year 1000, 1000 to 2000, then you should center on 
the average value of the proxy series for the period 1902 to--
	CHAIRMAN BARTON.  In which there is better data.  I mean, 
they--there could be a plausible reason why they did what they did, 
the more accurate data, they are more certain of it?
	DR. WEGMAN.  Well, they are more certain of the temperature 
data but the net effect of the decentering is to preferentially 
pick out these--
	CHAIRMAN BARTON.  But what they should have done was if they 
are going to measure from one 1000 to 2000, they should have used 
all the data points and came up with the mean and centered wherever 
that mean was?
	DR. WEGMAN.  That is correct, yes.
	CHAIRMAN BARTON.  Thank you.
	MR. WHITFIELD.  And I think the reason that is important is 
that when you make a categorical statement that the 1990s were the 
warmest decade in a millennium and that 1998 was the warmest year 
in the 1,000, I mean, it is difficult to make a statement like that
 categorically if the centering is not correct.  Would you agree 
with that?
	DR. WEGMAN.  Yes, I agree.
	MR. WHITFIELD.  And I think that is the whole basis of this 
hearing because this hockey stick--all of us are concerned about 
global warming but I do think we have an obligation and 
responsibility--everyone has latched onto this hockey stick and 
almost created a panic in a way, and maybe we should be panicked, 
but I think it is important that we understand how the hockey stick 
came about, and that is what we are talking about today.  Now, 
Dr. North, do you agree with Dr. Wegman's centering analysis or not?
	DR. NORTH.  I do.  I think that he is right about that.  
However, you know, we have to be careful here and not throw the 
baby out with the water.
	MR. WHITFIELD.  Right.
	DR. NORTH.  Because there have been other analyses, papers
 published after the Mann papers in which people just took a simple 
average.  Dr. Crowley wrote a paper just a short time after that in 
which he didn't use the principal component analysis at all.  He got
 essentially the same answer.  And so--
	MR. WHITFIELD.  Is that what we refer to as the CPS analysis?
	DR. NORTH.  I don't know what the initials--but he just took 
the average instead of dealing with the data the way one does it in 
the principal component analysis, so what I am arguing, and some 
other people have also done this same, there have been many studies 
later that don't use principal component analysis and the ones that 
I showed you, it is not there now--
	MR. WAXMAN.  Mr. Chairman.
	DR. NORTH.  They don't all use principal component analysis.
	MR. WHITFIELD.  Yes?
	MR. WAXMAN.  Will you yield to me?   I am just wondering if 
Dr. Wegman is familiar with Dr. Crowley's way of handling the 
statistics and if he thinks that the conclusions are suspect in the 
Crowley study.
	DR. WEGMAN.  Well, let me say that simple averaging of 
proxies, depending on how the proxies are selected, can yield the 
same kind of results.  In fact, if--I don't know if you can put up 
my backup slide, backup figure number 2, the backup figure number 
2 shows--
	MR. WHITFIELD.  Well, are we putting this graph up?  Where 
is this graph?  Okay.  There we go.  Okay.
	DR. WEGMAN.  This is using the CPS, simple averaging proxy
 methodology, just like the principal components, and by doing the 
simple averaging of proxies appropriately selected, you can 
reconstruct the same shape that you had with the principal 
component-type methodology.  So it is possible depending on how 
you approach this.
	MR. WHITFIELD.  So you can do a lot of things, just 
depending upon what data you use, what the centering is and so 
forth?
	DR. WEGMAN.  Exactly.
	MR. WHITFIELD.  Now, let me just ask both of you one question 
quickly.  My time has been used by other people.
	MR. WAXMAN.  I would like to ask unanimous consent that the 
chairman be given two additional minutes, but are you critical--
because that was my question--are you critical of his methodology in 
reaching the same conclusion?
	DR. WEGMAN.  I am saying that it is quite possible to use the 
CPS, the averaging methodology, and come to the same conclusion that 
Dr. Mann had.  I am not saying he did that because I haven't studied 
his paper in such detail as to be willing to say that.
	MR. WHITFIELD.  Well, let me just ask you on this whole 
issue of scientific analysis and scientific collaboration and so 
forth, you mentioned this social networking, for lack of a better 
term.  I mean, like any other profession, scientists, statisticians,
they deal with each other, they know each other, they write articles
 together and so forth.  But how serious is this issue of bodies 
making scientific reports and getting into a pattern of talking to 
the same people all the time about the same thing and they all have 
the same views?  Is that a significant problem or not?
	DR. WEGMAN.  I think it potentially can be.  It would be 
naive to think that there are not competing social networks within 
a discipline area.  Sometimes the competing social networks keep each 
other in check.  In the statistical arena, for example, there is a 
group of people who view themselves as classical statisticians.  
There is a group of people who view themselves as Bayesian 
statisticians.  As one of our reviewers said, Heaven help you if 
you get a reviewer from a competing social network.
	MR. WHITFIELD.  Okay.
	DR. WEGMAN.  And I think it would be naive to think that 
these things don't exist.  They exist in peer review journals, 
they exist in reviews of proposals submitted to the NSF and other
 organizations.
	MR. WHITFIELD.  Would you like to make a comment about this 
whole issue, Dr. North?
	DR. NORTH.  Well, I would be pleased to.  There are several 
matters here.  Social networking, it does seem to me to be a little 
bit of a problem to pick out that this young scientist got busy and 
found himself 43 coauthors.  I think a lot of us would look at that 
and say my, he is quite a charismatic young man who has gone out and 
found himself 43 collaborators.  That is something that I would 
probably look very favorable on if I were considering him for 
tenure.  And so there is that.  Now, do people collaborate and 
think similarly?  Of course they do.  But, you know, if you look 
back at the history of, say, quantum mechanics in the early 1920s, 
it was Einstein, Bohr, Heisenberg, all these people.  I am sure if 
you did a similar analysis, you would probably find something very 
like that, but in fact these guys hated each other.  I mean, they 
were very, very competitive.  And if you look at the 43 authors, 
I am sure that not all of them like to go out and have a beer 
together.  This is pretty competitive business, and I will tell 
you, if somebody can find a way to knock down someone else's theory, 
that is their road to recognition and fame.  We all do that.  That 
is part of the game and we really enjoy that part of the game.  So 
yes and no.
	MR. WHITFIELD.  All right.  Thank you.  My time has expired 
and I will recognize Mr. Stupak.
	MR. STUPAK.  Mr. Chairman, because of time constraints, I 
am letting Mr. Waxman go now and I will catch the next round.
	MR. WAXMAN.  Thank you very much, Mr. Stupak and Mr. 
Chairman.  That was an interesting analysis, Dr. North.  We are
 sometimes sheltered by our own politics but it looks like 
academics have their politics.
	DR. NORTH.  They do.
	MR. WAXMAN.  And I guess we should take that into 
consideration, but I don't think we doubt all science because 
experts agree with each other or that they are competing with 
each other.  Is that--
	DR. NORTH.  That is correct.  You know, the process works.  
You know, as they say, it is a little like making sausage.  You 
have heard that one.
	MR. WAXMAN.  On June 7, 2005, 11 National Science academies 
issued a joint statement calling on world leaders "to acknowledge 
that the threat of climate change is clear and increasing" and in 
their joint statement, the science academies of Brazil, Canada, 
China, France, Germany, India, Italy, Japan, Russia, the United 
Kingdom, and the United States declared, "There is now strong 
evidence that significant global warming is occurring."  They 
also stated that it is likely that most of the warming in recent 
decades can be attributed to human activities.  Mr. Chairman, I 
would like to ask unanimous consent that this statement from the 
premiere scientific institutions be placed in the record.
	MR. WHITFIELD.  Without objection.
	[The information follows:]
	
MR. WAXMAN.  Dr. North, I would like to begin with you.  Do you agree 
with the statement of these premiere institutions that there is now 
strong evidence that significant global warming is occurring and 
that it is likely that most of the warming can be attributed to 
human activities?
	DR. NORTH.  Yes, I do.
	MR. WAXMAN.  And Dr. North, the national science academies 
also state that the scientific understanding of climate change is 
sufficiently clear to justify nations taking prompt action.  They 
say it is important that we take cost-effective steps now to reduce 
our emissions or else it will be more costly to act in the future.  
Again, do you agree with that statement?
	DR. NORTH.  Well, now you are stepping a little bit beyond 
my role here.  I will talk about the science but what we ought to 
do is somebody else's business.
	MR. WAXMAN.  I am concerned that some are going to hear about 
Dr. Wegman's statistical criticism of the early Mann study and 
somehow conclude that global warming is still an open question.  In 
order to put the overall importance of this issue in context, I 
would like to ask you about some of the other evidence of global 
warming.  Are the Mann studies the basis for the ice core studies 
that give us data going back hundreds of thousands of years?
	DR. NORTH.  No.
	MR. WAXMAN.  Are the Mann studies the basis for the recorded
 atmospheric temperature records that we have maintained for the 
last 150 years?
	DR. NORTH.  No.
	MR. WAXMAN.  Dr. Crowley is going to testify later today 
that although the Mann study was influential in the IPCC's 2001 
assessment, the studies, which demonstrated that the instrumental 
record and the models could not be reconciled without an 
anthropogenic greenhouse influence, were even more influential.  
Were those studies based on the Mann studies?
	DR. NORTH.  I don't think so.  I am sorry.  I didn't hear 
everything you said.
	MR. WAXMAN.  Well, Dr. Crowley is going to tell us that--
	DR. NORTH.  He will talk about that, sure.
	MR. WAXMAN.  --although the Mann study was influential with 
the IPCC's 2001--
	DR. NORTH.  Well, it was part of the report.  It was a part 
of the report.
	MR. WAXMAN.  Right.
	DR. NORTH.  But as I have said, it is only one of several 
lines of evidence that are used in drawing those conclusions.
	MR. WAXMAN.  And so therefore you have further studies that 
seem to come to similar conclusions?
	DR. NORTH.  There are other studies, and they were shown 
on the graphic that I showed you.
	MR. WAXMAN.  And they weren't based on the Mann studies, 
were they?
	DR. NORTH.  They were not based on the Mann studies.  Now, 
there are cases where they use the same data so there is some 
correlation and that is what I think Dr. Wegman referred to and 
that is correct.  See, there is only a limited amount of data, 
so--
	MR. WAXMAN.  In 2005, two research teams led by scientists 
at the Scripps Institution for Oceanography and NASA's Goddard 
Institute for Space Studies published studies in Science magazine 
that concluded that not only is the Earth's air and land warming, 
but the oceans are warming as well and that heating has penetrated 
more than 1,000 feet into the ocean's depth.  Jim Hanson, director 
of the NASA Goddard Institute for Space Studies and the lead author 
of one of the studies, called these findings "the smoking gun of 
global warming."  Dr. North, are these studies in any way based on 
the Mann 1998 and 1999 studies?
	DR. NORTH.  No, not at all.
	MR. WAXMAN.  In July 2005, Nature magazine published a study 
by Dr. Kerry Emanuel of M.I.T. who found that the destructive power 
of hurricanes is increasing along with ocean temperatures.  Dr. 
Emanuel found that the total destructive potential of hurricanes has 
increased markedly during the last 30 years.  While natural cycles 
in the pattern of ocean circulation likely played a role, 
Dr. Emanuel attributes at least part of the increase to global 
warming.  Just last month the publication Geophysical Research 
Letters published a new study by Dr. Kevin Trenberth and Dr. Dennis 
Shea of the National Center for Atmospheric Research which concludes 
that global warming fueled hurricane intensity in the waters of the 
tropical North Atlantic in 2005, while natural cycles were only a 
minor factor.  Dr. North, are these papers by Dr. Emanuel, 
Dr. Trenberth, and Dr. Shea in any way based upon Mann's 1998 and 
1999 studies?
	DR. NORTH.  No, no.
	MR. WAXMAN.  Drs. Mears and Wentz published an article in 
Science magazine in August 2005 that resolves a longstanding conflict 
in the global warming debate.  For years global warming naysayers, 
based on the work of Dr. John Christy at the University of Alabama, 
have argued that satellite data showed that the Earth's atmosphere 
was warming far slower than the Earth's surface.  These scientists 
reanalyzed the raw satellite data and found that the lower atmosphere 
is actually warming slightly faster than the surface in agreement 
with the theory and models.  These scientists found that the 
previous analysis of the satellite data had inaccurately corrected
 for changes in the satellite's measurement time resulting from the 
decay of their orbit.  Dr. Christy has now acknowledged his mistake 
and has adjusted his data series, making it much more consistent 
with other results.  Dr. North, is the Mears and Wentz study in any 
way based on Mann's 1998 and 1999 studies?
	DR. NORTH.  Absolutely not.  Dr. Christy was actually on our
 committee, by the way.
	MR. WAXMAN.  He was on--
	DR. NORTH.  He was on the NAS committee.
	MR. WAXMAN.  Finally, if we were to--
	DR. NORTH.  If I may just add one thing.  You know, just 
because a paper is published, it goes out for the community.  
People--the wolves attack, and this particular study by Spencer and 
Christy took many years before the error was finally found.  It 
doesn't mean these guys are villains.  It is just that--
	MR. WAXMAN.  If you knew that Dr. Mears--
	DR. NORTH.  --they did their best.  It took years to find 
that mistake.
	MR. WAXMAN.  If you knew that those two scientists were 
friends with--
	MR. WHITFIELD.  Would the gentleman excuse me one minute?  
Did you say it took many years before the error was discovered?
	DR. NORTH.  Before the error in the Spencer-Christy study 
using satellite data was found.  It was a good-faith effort on their 
part but it turned out to be wrong.
	MR. WAXMAN.  If you knew that these gentlemen were friends 
with Dr. Mann, would that make you suspect their work?
	DR. NORTH.  I have no idea whether they know him.
	MR. WAXMAN.  Finally, if we were to sweep away the Mann 
studies and forget that they existed, would that in any way erode 
the validity of any of the studies I just mentioned?
	DR. NORTH.  I do not think it would.
	MR. WAXMAN.  Would there still be--
	DR. NORTH.  We wouldn't--
	MR. WAXMAN.  Would there still be a scientific consensus 
that global warming is happening, it is being caused by humans and 
that some people think it is time to act now?
	DR. NORTH.  Yes, I think there would be.
	MR. WAXMAN.  And Dr. North, my point in asking you about 
these other studies is simply to illustrate how wrong it would be 
for anyone to draw sweeping conclusions from a statistical criticism 
of one or two studies from 8 years ago.  Unfortunately, the Republican
 majority on this committee has been completely content to sit back 
and ignore global warming.  They ignored it while President Bush 
frayed our relationships with our international allies over global 
warming.  They ignored it while the committee crafted an energy 
policy that exacerbates global warming and they continue to ignore 
it as evidence piles up about the severity of the situation.  
Instead, we spend our time attacking climate researchers who have 
infuriated the oil lobby by contributing to our knowledge of this 
issue, and apparently that is the one thing that the Majority 
simply cannot ignore.  My time is just about expired, and we have a 
vote on the House floor.  I thank the witnesses for their testimony 
and Dr. North for responding to my questions.
	MR. WHITFIELD.  Mr. Chairman, we have 8 minutes to vote on 
the floor.  Would you like to start your questions and come--
	CHAIRMAN BARTON.  I would recommend that we recess and let 
us go vote, give our witnesses a chance to have a personal convenience 
break and then come back.
	MR. WHITFIELD.  We have two votes on the floor.  The first 
vote will be over in about 10 minutes and then we will have another 
one, so we will reconvene at about 12:15.
	[Recess.]
	MR. WHITFIELD.  At this time I recognize the Chairman for 
his 10 minutes of questions.
	CHAIRMAN BARTON.  Thank you, Mr. Chairman.  I appreciate the 
courtesy and I appreciate our witnesses here today.  My first 
question is a personal question to you, Dr. Wegman, and it is not 
normally one that I would even think about asking but there has 
been some attempt to portray you as a pawn of this committee or me
 personally.  I am told that you voted for Vice President Gore for 
president in the year 2000.  Is that correct?
	DR. WEGMAN.  That is correct.
	CHAIRMAN BARTON.  So you are by no means a radical, wild-
eyed, hard core, right wing Republican?
	DR. WEGMAN.  No, sir.
	CHAIRMAN BARTON.  Okay.  How often, if ever, have you been 
in Texas?
	DR. WEGMAN.  I was in Texas in hill country a few weeks ago 
but I have been to Houston a few times, interacting in my social 
network with David Scott.
	CHAIRMAN BARTON.  But you are not--you and I until this 
morning have had no phone calls, no e-mails, no--
	DR. WEGMAN.  I didn't even know what you looked like until--
	CHAIRMAN BARTON.  Which is a blessing for you, right?
	DR. WEGMAN.  No, sir.
	CHAIRMAN BARTON.  All right.  Now, let me ask you, Dr. North,
 obviously you and I went to--I attended the school where you have 
been an illustrious professor for a number of years and I asked you 
during the break if you and I had met and you said that we had met 
on an airplane once.
	DR. NORTH.  We had a 2-minute--a 30-second conversation.
	CHAIRMAN BARTON.  So you and I have had some personal 
interaction, but that is it.  Again, there is no real association in 
terms of continuing basis or anything.  When Mr. Waxman was here, he 
was asking some questions of you, Dr. North, about headlines that had 
occurred and papers that had been issued that state the possibility 
or the probability that global warming is real and it is caused by 
humans, and it is your personal opinion that global warming is real 
and that a large part of the reason it is real is because of human 
emissions of greenhouse gases.  That is a fair statement of yours?  
You need to push that button, put your microphone on.  Let the record 
show that he said yes.  But we have some headlines here that have 
been purported to be because of global warming.  Dr. North, one of 
them is that more frogs are dying as the planet warms.  Are you aware 
of that?
	DR. NORTH.  I have heard of it.
	CHAIRMAN BARTON.  You have heard of that.  How about because 
of global warming, irrigation fuels warmer temperatures in 
California's central valley, are you aware of that?
	DR. NORTH.  I have not heard of that one.
	CHAIRMAN BARTON.  Okay.  How about the irony of global 
warming, more rain, less water?
	DR. NORTH.  I am familiar with that idea.  I don't know if 
I have seen that headline.
	CHAIRMAN BARTON.  Global warming could sour the wine 
industry?
	DR. NORTH.  I don't--
	CHAIRMAN BARTON.  Poison ivy grows faster, bigger, more 
irritating?
	DR. NORTH.  No, I don't--
	CHAIRMAN BARTON.  Global warming weakens trade winds.  
Global warming's next casualty, igloo.  Global warming could 
overwhelm storm drains.  Strange things happening to Pacific 
coast marine life.  Global warming might create lopsided planet. 
Global warming makes seas less salty.  Space ring could shade 
Earth and stop global warming.  My point is, a lot of people are 
jumping on the global warming bandwagon and there is no question it 
is serious, there is no question that eminent people like yourself 
believe the causality of human emissions.  I don't have a problem 
with that.  I mean, you pointed out in your testimony what science 
is supposed to be about.  My problem is that everybody seems to 
think that it is automatically a given and that we shouldn't even 
debate the possibility of it and we probably shouldn't debate the 
causes of it, and I think that is wrong.  That is one of the reasons 
that we are holding this hearing.  
I want to put up the digitized temperature curve number 2 that 
Dr. Wegman was referring to.  We determined that you couldn't prove 
the hockey stick by using the data points, Dr. Wegman concluded that, 
and so Mr. Waxman said well, that is okay but there are other studies 
and one of them is the study of a methodology that was not using the
 methodology that Dr. Mann used, and that is--it is kind of an S 
curve and--that is not?
	DR. NORTH.  Figure number 2 is the one that--
	CHAIRMAN BARTON.  That one right there.  Now, in that curve 
there, Dr. North, the highest point looks to me to be about the year 
1300.  Would you agree with that?
	DR. NORTH.  Well, that is what it shows on that graphic.
	CHAIRMAN BARTON.  Okay.  But it is definitely higher than 
the 1900s.
	DR. NORTH.  Higher than--I think that curve goes up to the 
middle of the 20th Century although I am not sure.
	CHAIRMAN BARTON.  But it is obvious--I am not saying that 
is the truth, okay, but I am saying, if that is a justification for 
global warming in that particular study, which I believe is 
purported to be a Crowley study, that is using average temperatures, 
that that particular graph shows the warmest period was somewhere 
between 1100 and 1400.  Is that correct?
	DR. NORTH.  Well, that is what the curve shows.  I cannot 
tell you where that one actually came from.  We used a graphic like 
that in our report just to give some perspective about how people 
thought the curve looked 15 year ago, 16 years ago, so we used a 
graphic like that.  I believe you have replotted it here.
	CHAIRMAN BARTON.  Now--
	DR. WEGMAN.  Let me be precise.  This is a curve from the 
IPCC 1990 report.
	DR. NORTH.  Sixteen years ago.
	CHAIRMAN BARTON.  Okay.  And let us go to the study--there 
is a comparison in Dr. Wegman's testimony of the Mann report and I 
believe this curve.  There are two--keep going.  There are two 
documents--yes--no, not that one.
	DR. NORTH.  Number 4 and 5, I think.
	CHAIRMAN BARTON.  Well, my question is, something happened 
between the chart that we up here that showed the early 1300s being 
the warmest period and Dr. Mann's study that obviously shows the 
20th Century, and my question is, what changed in the modeling or 
the methodology or the data set?  Because Dr. Mann wipes out that 
early warming period.  It is just not there.
	DR. NORTH.  Is that for me?
	CHAIRMAN BARTON.  It could be for either one of you.
	DR. NORTH.  Well, there is more data available 10 years later 
than there was in that first report.  In fact, I have a feeling that 
that first report--I hope you will ask Crowley that later because I 
think he will know more about it than--
	CHAIRMAN BARTON.  Well, is it now the consensus of the 
majority of the scientific community that this early warming period 
just didn't exist?
	DR. NORTH.  No, I think that there is good evidence that such 
a medieval warm period did exist, however, it may not have existed at 
the same time at different locations on the Earth, and I could give 
you some information about that.  For example, if you look in 
Greenland, there was a very distinct warming period in that time 
around--between 1000 and 1200.  In fact, there were colonies of 
people who lived there from Denmark and their civilization 
disappeared there.  They went back to Denmark or died out, I am not 
sure which.
	CHAIRMAN BARTON.  But I mean, it is striking--
	DR. NORTH.  So there is evidence, historical and so on, that--
	CHAIRMAN BARTON.  It is on page 15 of your report, and I have 
the prepublication copy.  You have the figure 03 at the top and then 
you have the figure 04 at the bottom.  Oh three is a schematic 
description of global warming that is the IPCC report of 1990 and 
then the 04 figure is the Mann graph, and it is just striking to me 
that there is no correlation between the two, or very little.
	DR. NORTH.  Oh, actually, if you look at the gray area in 
the Mann graph, that is the area where the curve could fall with 
some reasonable probability.  That is their error margin.
	CHAIRMAN BARTON.  Let me ask you--
	DR. NORTH.  If you look at the family of our curves that I 
showed in our graphic, the family of curves that were derived by 
using several different methods and different sources, you find that
 that family of curves really does fall pretty close to where the 
gray is here, especially if you put margins of error on each of 
those comparable to these.
	CHAIRMAN BARTON.  Let me ask you--
	DR. NORTH.  And we would dispute how accurately Mann and 
company did that.
	CHAIRMAN BARTON.  I understand that.
	DR. NORTH.  That is another matter.
	CHAIRMAN BARTON.  I understand that.  It looks like my time 
is expired, so I want to ask one more question.  Dr. North, do you 
dispute the conclusions or the methodology of Dr. Wegman's report?
	DR. NORTH.  No, we don't.  We don't disagree with their 
criticism.  In fact, pretty much the same thing is said in our 
report.  But again, just because the claims are made, doesn't 
mean they are false.
	CHAIRMAN BARTON.  I understand that you can have the right 
conclusion and that it not be--
	DR. NORTH.  It happens all the time in science.
	CHAIRMAN BARTON.  Yes, and not be substantiated by what you 
purport to be the facts but have we established--we know that 
Dr. Wegman has said that Dr. Mann's methodology is incorrect.  Do 
you agree with that?  I mean, it doesn't mean Dr. Mann's 
conclusions are wrong, but we can stipulate now that we have--and if 
you want to ask your statistician expert from North Carolina that 
Dr. Mann's methodology cannot be documented and cannot be verified 
by independent review.
	DR. NORTH.  Do you mind if he speaks?
	CHAIRMAN BARTON.  Yes, if he would like to come to the 
microphone.
	MR. BLOOMFIELD.  Thank you.  Yes, Peter Bloomfield.  Our 
committee reviewed the methodology used by Dr. Mann and his coworkers 
and we felt that some of the choices they made were inappropriate.  
We had much the same misgivings about his work that was documented 
at much greater length by Dr. Wegman.
	MR. WHITFIELD.  If I may interrupt just one minute.  We 
didn't swear you in so I want you to swear now that the testimony you 
gave was the truth.
	[Witness sworn]
	MR. WHITFIELD.  Thank you.
	CHAIRMAN BARTON.  I would like to submit for our record an 
e-mail that was received, and I would be more than willing to share 
it with the Minority if they have not seen it before.  They have it? 
 It is an e-mail from Yasmin Said to Peter Spencer and it says, "To 
whom it may concern:  I have read the reports of Chairman Barton and 
Chairman Whitfield entitled "ad hoc committee report on the hockey 
stick global climate reconstruction by Edward J. Wegman, David Scott, 
and Yasmin H. Said" and what follows this work of Wegman, Scott, and 
Said is simply referred to as Report.  The assessment of previous 
results given in the Report is correct.  The Report is entirely 
correct in stating that the most rudimentary additive model, the 
model of a simple temperature signal with superimposed noise, is 
not adequate to describe the complex relationships involved in 
climate dynamics.  There is no physical process found in nature 
that does not involve feedback in one form or another to regulate
 the action of the system.  The statistical methods and models 
described in the report use more variables and make possible the 
construction of more elaborate reconstructions that allow feedback 
and interactions.  The report represents the correct way to proceed.
 It is especially important to bring the professional statistical 
community into the picture in order to assure that a sound 
analytical foundation is secured in the continuing development of 
this program.  Sincerely, Enders A. Robinson, member of the National 
Academy of the USA, fellow of the European Academy of Scientists, 
professor emeritus and the Maurice Ewing and J. Lamar Rozelle, 
Chair, Department of Earth and Environment, Columbia University."  
And I yield back.
	MR. WHITFIELD.  Thank you.  At this time I recognize Mr. Inslee.
	MR. STUPAK.  Wait a minute.  Did we accept this e-mail that 
was read into the record, or what?
	MR. WHITFIELD.  Well, he asked for unanimous consent if you 
all--do you have an objection to it?
	MR. STUPAK.  Well, let us object for now.  We will ask some 
questions of it later.
	MR. WHITFIELD.  They object to it being entered until they 
clarify a few things with that.
	CHAIRMAN BARTON.  But they had the document.  I don't want 
them to accept it if they have not seen it.  I was told that they had 
seen it.
	MR. WHITFIELD.  We were told that you all had it last night 
but is that not--
	CHAIRMAN BARTON.  But certainly we don't want to put anything 
in that hadn't been cleared.  Mr. Chairman, they have every right to 
object if they haven't seen it.
	MR. WHITFIELD.  Well, while they are discussing it, 
Mr. Inslee, why don't you proceed with your questions. 
	MR. INSLEE.  Thank you.  Dr. Wegman, can you cite to us the 
first three laws of thermodynamics?
	DR. WEGMAN.  Probably not.
	MR. INSLEE.  And you shouldn't be ashamed of that because you 
are a statistician, not a physicist.
	DR. WEGMAN.  That is correct.
	MR. INSLEE.  But it is important for us to talk about that 
in the context of some things I want to ask you.  Because I believe 
reviewing the literature, and I spent some time doing this, it is 
beyond any reasonable doubt that there is a strong worldwide 
scientific consensus that human activities are putting carbon 
dioxide and other global warming pollutants in the air in a way 
that is changing our climate in fundamental ways.  I want to ask 
you some questions about your testimony here today.  I want to 
refer you to a chart that is up on the screen to your left, and it 
shows concentrations of carbon dioxide in the Earth's atmosphere 
going back 160,000 years and basically what it shows is that the
 concentrations now which are in the lower right-hand circle are 
higher than they have been in any time in the last 160,000 years.  
They also show that those concentrations of carbon dioxide will go 
up approximately doubling in the next century by the year 2100 
unless this Congress pulls its head out of the sand and does 
something about it.  Now, the question I want to ask you, these 
carbon dioxide samples are beyond dispute because of direct 
physical measurement of old air trapped in glaciers and that they 
are not subject to any scientific doubt whatsoever.  Neither as far 
as I know is there any question but that the carbon dioxide levels 
will significantly increase in the order of doubling of pre-
industrial times in the next century if we do not act.  So the 
question I ask you, is anything in your criticism of the Mann 
report in any way suggests that those conclusions I just stated to 
you that are reflected on this graph regarding carbon dioxide levels 
are faulty?
	DR. WEGMAN.  No, I don't believe they are.
	MR. INSLEE.  So if you accept the first three laws of 
thermodynamics and basic chemistry and our ability to judge CO2 
levels and if you accept the premise that carbon dioxide in the 
atmosphere has the capacity of essentially trapping heat in the 
energy system of the Earth--by the way, do you accept that 
proposition?
	DR. WEGMAN.  I don't know about the second proposition.  I do 
not know the mechanisms for trapping heat.
	MR. INSLEE.  Well, I will just tell you, the mechanisms of 
carbon dioxide essentially traps heat in infrared range of a 
frequency.  Light comes in an ultraviolet range, it bounces back in 
an--not really bounces back but emitted in an infrared range and 
carbon dioxide traps it.  It traps it like a blanket, as a crude 
metaphor.  Now, what we know beyond a shadow of a doubt is that 
carbon dioxide in the next century is going to be at levels double 
any time in the last 160,000 years and double what it was in pre-
industrial times.  Now, does your criticism of Dr. Mann's research 
in any way suggest that it would not be a good idea to reduce our 
carbon dioxide loading into the atmosphere?
	DR. WEGMAN.  My expertise does not extend to global warming 
and I have no position on this.
	MR. INSLEE.  Well, I think that is important for you to say 
that because what we are finding here is that there is this enormous 
worldwide consensus.  I look at the joint academy statement--this is 
a joint academy statement of every science academy in the 
industrialized world and every single one of them state that it is 
a consensus that human activity is causing changes to the climate.  
I will just read directly.  "It is likely that most of the warming 
in recent decades can be attributed to human activities.  This 
warming has already led to changes in the Earth's climate."  It is 
signed by Canada, Germany, France, Italy, Japan, United Kingdom, 
Russia, China, Brazil, and the National Academy of Sciences under 
the administration of George Bush.  Now, I guess the question to 
you is, do you have any reason to believe all those academies should 
change their conclusion because of your criticism of one report?
	DR. WEGMAN.  Of course not.
	MR. INSLEE.  Why not?
	DR. WEGMAN.  Because my report was very specific on a very 
specific issue that was asked of me and we answered that very 
specific question.
	MR. INSLEE.  Well, let me suggest another reason.  The 
reason you don't suggest these academies are wrong is because they 
have a mountain of evidence from ice core data, through glacier 
data, to ocean acidification, to radar data, to surface and deep 
ocean temperature data that indicate that this world is changing 
because we are putting too much carbon dioxide in it.  Isn't that 
right?  That is why you are not suggesting they change their report.
	DR. WEGMAN.  Well, there is the old statistical process that 
says association does not mean causation.
	MR. INSLEE.  Well, there is another statistical by Mark 
Twain is that there are three kinds of lies:  lies, damn lies, and 
statistics, but I won't bring that one up.  I want to ask--
	DR. WEGMAN.  Of course, he is not a statistician either.
	MR. INSLEE.  Dr. North, I want to quote--in your testimony 
you said, "However, our reservations with some aspects of the 
original papers by Mann et al. should not be construed as evidence
 that our committee does not believe that the climate is warming and 
will continue to warm as a result of human activities."  You go on 
to say, "The scientific consensus regarding human-induced global
 warming would not be substantively altered if for example the 
global mean surface temperature 1,000 years ago was found to be was 
warm as it is today."  Now, in listening to your testimony, what I 
take from this is that even if we were to conclude that Dr. Mann 
had never been born, the study had never been done, conclude even 
if there was a medieval warming period that approximated 
temperatures today, even if we were to accept that as a verity, 
even if we knew that today, what I am hearing your testimony tell 
us is that there is enough evidence of other methods and other 
dynamics at work in the climate today that we can with a reasonable 
degree of assurance conclude that humans are responsible for at 
least a portion of the changes in temperatures.  Is that a fair 
statement?
	DR. NORTH.  Well, let me separate myself from the report 
now.  I believe that is true but we didn't address that issue in 
the report.
	MR. INSLEE.  And could you at least in summary fashion tell 
us about the other evidence that leads to your conclusion other than 
Dr. Mann's?
	DR. NORTH.  Well, let me mention a few things that my 
colleague on the committee, Kurt Cuffey from the University of 
California-Berkeley sent.  So this is a little about the medieval 
warm period.  It takes a couple minutes so I apologize for that.  
So Greenland shows a clear signal of both medieval warmth and 20th 
Century warming.  These are recorded unambiguously in isotopes and 
boreholes, nothing to do with this extrapolation method.  The 
medieval was warmer than the 20th Century up to about 1990, but you
 know it has warmed quite a bit in the last 15 years, so another 
piece of evidence is Ellesmere Island.  This is in the Canadian 
Arctic and there is an icecap there.  It also shows evidence of a 
medieval warm period and 20th Century warming and the isotopes and 
melt records.  The melt in particular shows summertime warmth in 
the 20th Century was greater than the medieval warm period, so 
there is that one.  The composite of all available low latitude--
this is Tibet and the Andes and there is things in Africa, 
Kilimanjaro.  Ice core, isotope records show the 20th Century 
climate is truly anomalous on the time scale of 2,000 years.  This 
is an objective quantitative measure of climate arising from 
physical processes.  We cannot, however, separate a pure 
temperature signal from it because these glaciers are influenced 
by both moisture availability and temperature because hydrology is 
important too.  All we can say is that the sum of the climate 
processes determining the isotope records have reached an anomalous 
state.  One more--two more.  Melt at the summit of Quelccaya--this 
is a big icecap in the Andes, the largest Andean icecap--was strong 
enough in the late 20th Century to destroy annual layering of 
isotopes which did not happen during the medieval period. Now, the
 tropics are a very interesting place to look at climate.  They are 
probably a little more representative of the global average, not 
as much natural variability in the tropics.  So we had melting 
recently in the Quelccaya glacier but it didn't happen in the 
medieval warm period.
	MR. INSLEE.  Doctor, I want to ask one quick question. My 
time is almost up.
	DR. NORTH.  I am sorry.
	MR. INSLEE.  Put the slide up on the acidification, Tracy, 
that one right there if I can.  Doctor, I made reference to 
acidification that is taking place in our oceans as a result of 
carbon dioxide going into the atmosphere, then going into solution
 in the oceans.  Could you briefly summarize that dynamic and what 
the state of our knowledge is about that?
	DR. NORTH.  I am not an expert on this.  I have seen the 
report and the essence is that as we increase carbon dioxide in the
 atmosphere, the carbon dioxide of course dissolves in seawater 
just as it does in Pepsi-Cola, so the greater the partial pressure 
of carbon dioxide in the atmosphere, the more that will be 
dissolved in the ocean and then you wind up with--by combining with
 other things, you wind up with a more acidic ocean so the pH of the 
ocean goes down, becomes more acidic.  This attacks the corals and 
other things.  So there could be something going on with aquatic 
life.  Again, we are really pretty far away from--
	MR. INSLEE.  And is that independent of temperature issues?
	DR. NORTH.  That is independent of temperature.
	MR. INSLEE.  So even if temperature doesn't go up, this 
dynamic can acidify the ocean?
	DR. NORTH.  That has been happening and I presume will 
continue to happen.
	MR. INSLEE.  Thank you.  Well, we would like to change that 
actually.  Some of us have ideas about that.
	DR. NORTH.  That is not my job.
	MR. WHITFIELD.  Mrs. Blackburn, you are recognized for 
10 minutes.
	MRS. BLACKBURN.  Thank you, Mr. Chairman, and thank you all 
for your patience as we work through our votes today.  Dr. Wegman, 
I have got three quick questions for you and Dr. North, I have got, 
I think one probably for you and I am going to try to finish so 
everyone gets their questions in before the next vote.  But 
Dr. Wegman, you said in your testimony that Dr. Mann's data is very 
obscure, incomplete, and disorganized, and I wanted you to expand 
on that and give us an example of how that data should have been 
presented, if you have something tangible.
	DR. WEGMAN.  Well, I had two things in mind.  First of all, 
when I read the paper originally, it took me probably 10 times to 
read it to really understand what he was trying to say.  He uses 
phrases that are not standard in the literature I am familiar 
with.  He uses, for example, the phrase "statistical skill" and I 
floated that phrase by a lot of my statistical colleagues and 
nobody had ever heard of that phrase, statistical skill.  He uses 
measures of quality of fit that are not focused on the kind of 
things typically we do.  We went to his website to try and figure 
out where his data was.  He has a website at the University of 
Virginia.  We basically downloaded everything that was in his 
FTP website to try and gather together--try and understand what 
was going on.  The materials tended to be very cryptic.  When we 
looked at the Fortran code that he wrote, it was very difficult 
to understand how you could, in the Fortran code you read in the 
data, but it was unclear where the data was and how you could 
actually read it in and the coding of the data, so all those 
things tended to make it very difficult to try and replicate anything 
that he did.  Ultimately, I believe it was in 2004, he published a 
corrigendum and it showed that some of the data that he used in 
the 1998 paper was not referenced in the 1998 paper and other 
material that he did reference in the 1998 paper was not actually 
used.  So there was a lack of clarity in both the archived data as 
well as the writing of the appear itself that I found difficult to 
decipher.
	CHAIRMAN BARTON.  Will the gentlelady yield just for--
	MRS. BLACKBURN.  I will yield.
	CHAIRMAN BARTON.  When you said his data was in Fortran 
	code, what is Fortran code?
	DR. WEGMAN.  Fortran is a computer programming language that 
	was invented in 1957.
	CHAIRMAN BARTON.  And when was the last time anybody else 
	than Dr. Mann used that code?
	DR. WEGMAN.  Well, I suspect--
	CHAIRMAN BARTON.  I knew it at Texas A&M in the 1960s and I 
	had not heard the term and I wanted to make sure we were 
	talking the same--
	DR. WEGMAN.  Well, certainly programming languages have 
	evolved dramatically over the years.  Most of my colleagues 
	use a software package called RS Plus.  Many people use Mat 
	Lab these days.
	CHAIRMAN BARTON.  The Fortran code is not something that 
	would be normally used today by too many people?
	DR. WEGMAN.  I would think in certain circles it might be 
	but it is reflective of the notion that there aren't--
	DR. NORTH.  Most climate models do use Fortran code.
	CHAIRMAN BARTON.  Oh, they do?
	DR. NORTH.  Yes.
	CHAIRMAN BARTON.  So that is standard?
	DR. NORTH.  It is standard in mathematical solution of these 
	kinds of problems, not statistics.  He is right about that.  
	So Mat Lab is coming on but Fortran is very commonly used 
	in large climate model work.
	CHAIRMAN BARTON.  Well, then I should be able to do some of 
	this because I can code in Fortran.  I yield back.
	MRS. BLACKBURN.  Dr. Wegman, I still want to come to you. 
	So what you are saying is that he--I want to go back to one 
	thing on the data that he chose to input on the website, he 
	was selective in the nature of what he chose to put in there 
	and I guess that is much like what we saw with the 
	calibration issue over the years that he used in that--
	DR. WEGMAN.  There were a large number of proxies that were 
	used in the 1998 and 1999 papers.  As a matter of fact, it 
	probably wasn't very selective.  He essentially threw
	everything including the kitchen sink into this data set.
	MRS. BLACKBURN.  I want to ask you a question that Dr. Crowley 
	makes a statement in his testimony that was submitted to us, 
	that the data is reused, Dr. Mann's data is reused because 
	it is the best data.  But you say that other papers cannot 
	claim to be independent verification if they reuse the same 
	data.  So I would like for you to speak to that and kind of 
	reconcile the differing views.
	DR. WEGMAN.  Well, in one of our plots we had a plot that 
	showed the data that was being used as the proxies versus 
	the 11 or 12 papers that had been published since 1998 and 
	the striking thing is, I think, that essentially there are 
	two methodologies that we talked about, the CPS methodology 
	and the CFR methodology, and my contention is that if you 
	use the same data and the same basic methodology, you can--
		MRS. BLACKBURN.  Then following on with that, if you
		were to structure an external statistical review for 
		climate papers that would guarantee to be an 
		independent verification of methods used, how would
		you structure this?
	DR. WEGMAN.  Well, I think there are a couple of approaches. 
	One of the analogies I kind of liked was that the folks that 
	do the hockey stick kind of thing call themselves--I think 
	they call themselves the hockey team and when games are 
	being played, you also need referees, so I think it would 
	be a good idea to have referees for the hockey games.  My 
	own feeling is that it would be useful as we said in one of
	our recommendations that there be an external review and 
	that it be funded as part of this kind of activity.  If you 
	have significant statistical methodology being used in a 
	scientific study, then you really ought to have statistical 
	review as well as the peer paleoclimate review.  I think 
	this extends beyond just paleoclimate stuff.  It is true, 
	for example, in biostatistics, biological science, medical 
	science, that there is typically a heavy involvement with 
	statistical review.  I think in terms of things like 
	sociology, psychology, there is heavy involvement with 
	statisticians in this kind of framework.  It appears to me 
	that in the physical sciences, the same mental set is not 
	typically done.
	MRS. BLACKBURN.  Thank you.  Dr. North, I have got a couple 
	of quick questions on surface records and satellite 
	measurements that I want to give to you but I have only got 
	a minute and a half left and I think I will submit these to 
	you and then ask for your response, and Mr. Chairman, I 
	will yield back so somebody else can get their questions on 
	the record before we go for another vote.
	MR. WHITFIELD. Thank you, Mrs. Blackburn.  At this time I 
	recognize Mr. Stupak.
	MR. STUPAK.  Thank you, Mr. Chairman.  Dr. Wegman, in your
	report you criticized Dr. Mann for not obtaining any 
	feedback or review from mainstream statisticians.  In 
	compiling your report, did you obtain any feedback or 
	review from paleoclimatologists?
	DR. WEGMAN.  No, of course not, but we weren't addressing 
	paleoclimate issues.  We were addressing--
	MR. STUPAK.  But you said you had difficulty understanding 
	some of the terms of art that Dr. Mann used and you had to 
	call your social network to figure it out so wouldn't it 
	have been helpful to have paleoclimatologists?
	DR. WEGMAN.  To say that I didn't contact any climate 
	people is not entirely accurate.  We have--
	MR. STUPAK.  But they weren't used in compiling your 
	report--that was the question--correct?
	DR. WEGMAN.  Well, I am not sure how to answer that.  I 
	certainly--
	MR. STUPAK.  Well, yes or no is probably the best way.  
	Did you have any paleoclimatologists when you compiled 
	your report?
	DR. WEGMAN.  Not on our team, but that doesn't mean I 
	didn't talk to any.
	MR. STUPAK.  Did anyone outside your social network peer 
	review your report?
	DR. WEGMAN.  Yes.
	MR. STUPAK.  Who was that?
	DR. WEGMAN.  Well, Enders Robinson.
	MR. STUPAK.  Is that the e-mail we were talking about 
	earlier?
	DR. WEGMAN.  Pardon?
	MR. STUPAK.  Is that the e-mail that was--
	DR. WEGMAN.  Yes.  So--
	MR. STUPAK.  When you do peer review--
	DR. WEGMAN.  Let me answer the question.  Enders Robinson, 
	Grace Waba, who is a member of the National Academy, Noel 
	Cressy, who is at the Ohio State University, Bill Wasorik, 
	who is at Buffalo State SUNY, David Banks, who is at Duke 
	University, Rich Schareen is the immediate past president 
	of the American Statistical--
	MR. STUPAK.  Let me ask you this question.  If you had a 
	peer review, when are peer reviews usually done?  Before 
	a report is finalized or after?
	DR. WEGMAN.  We had submitted this and had feedback from-
	-
	MR. STUPAK.  No, no, I am talking about general peer 
	review.  If you are going to have a peer review, don't 
	you usually do it before you finalize your report?
	DR. WEGMAN.  Yes.
	MR. STUPAK.  Well, your peer review was after you 
	finalized it?
	DR. WEGMAN.  No, it was before.  We submitted this long 
	before.
	MR. STUPAK.  Well, when was your report finalized?
	DR. WEGMAN.  I think we dated the final copy about 
	4 days ago.
	MR. STUPAK.  Four days ago, so that would be about 
	July 15.  This e-mail sort of indicates it is July 17 
	that you asked for this peer review.
	DR. WEGMAN.  I had feedback from Enders much earlier 
	han that.  We had asked him to send material to us for 
	purposes of coming here.
	MR. STUPAK.  Well, the e-mail read into the record is 
	Tuesday, July 18, so that would be 3 days after you 
	finalized your report.
	DR. WEGMAN.  I am sorry.  We--
	MR. STUPAK.  Have you seen this e-mail, the one that--
	DR. WEGMAN.  Yes, of course I have.  Dr. Robinson saw 
	our material before the 18th, before the 17th, before 
	the 16th.  He gave us feedback.  We incorporated that. 
	He gave us feedback verbally.  We incorporated that
	because there was some interest in getting this report
	to the committee.
	CHAIRMAN BARTON.  Would my friend from Michigan yield 
	for one simple question on this same point?
	MR. STUPAK.  Sure.
	CHAIRMAN BARTON.  Dr. Wegman, do you object to 
	Mr. Stupak or anybody in the Minority submitting your 
	report for a peer review as long as the peers are 
	qualified in statistical analysis?
	DR. WEGMAN.  Not at all.
	CHAIRMAN BARTON.  Thank you.
	MR. STUPAK.  In doing peer reviews, do scientists who 
	do the report, do they usually submit to people they 
	want to do the peer review?  Isn't that sort of an 
	independent review?
	DR. WEGMAN.  This is basically the same mechanism that 
	was used at the National Academy.  The national--you 
	know, this is not a--
	MR. STUPAK.  Did you ask these people to do your peer 
	review?
	DR. WEGMAN.  Yes.
	MR. STUPAK.  So would they be part of your social 
	network?
	DR. WEGMAN.  No.  When I talk about social network, I am 
	talking about people with whom I have actively 
	collaborated in writing research papers.
	MR. STUPAK.  It sounds--
	DR. WEGMAN.  None of these people have actively 
	collaborated with me in writing research papers.
	MR. STUPAK.  Isn't the same kind of social network you 
	criticized Dr. Mann on because the people that reviewed 
	his were paleoclimatologists?
	DR. WEGMAN.  Were the people that had actually worked with 
	and published papers with.
	MR. STUPAK.  And you have published papers with some of these 
	people that peer reviewed your report?
	DR. WEGMAN.  No.  I just told you no, I haven't.
	MR. STUPAK.  Let me ask you this.  Page 34 of your report, I 
	think you have it in front of you, your 52-page summary there,
	you have a figure that you say is a digitized version of the 
	temperature profile in the IPCC assessment report of 1990.  I 
	take it you read the 1990 IPCC report?
	DR. WEGMAN.  I am sorry.  What page was it?
	MR. STUPAK.  Page 34 of your report.  It is figure 4-5.  It 
	is this one right here.  We have had some--it has been 
	referred to as figure 2 on the screen a couple times today.
	DR. WEGMAN.  No, I have not been able to obtain a copy of the 
	1990 report.
	MR. STUPAK.  Well, then you must have at least discussed this 
	temperature profile.
	DR. WEGMAN.  The temperature profile that was published in 
	1990 I believe was related to the European temperatures and 
	was a cartoon--essentially a cartoon.  The point of our 
	discussion here was not that we were trying to say that this 
	was what happened in 1990.  The point of our discussion was 
	that you could reproduce this shape from the CPF, CFP and the 
	climate plus--whatever--CPS methodology so we are not 
	endorsing that this was the temperature that was thought of 
	in 1990.  We are simply using this as an example.
	MR. STUPAK.  Were you endorsing 1300 as being a real high 
	temperature time?  Were you endorsing it in your report?
	DR. WEGMAN.  No, we have not said that.
	MR. STUPAK.  What was the 1990 IPCC temperature profile based 
	on?  Basically what was this based on?  You are a statistician.
	DR. WEGMAN.  This--
	MR. STUPAK.  Was this based on data?
	DR. WEGMAN.  As I just said moments ago, this was a cartoon I 
	believe that was supposed to be representing a consensus 
	opinion of what global temperature was like in 1990 as
	published by the IPCC.
	MR. STUPAK.  Well, is this cartoon then--again, I am on page 
	34, I am reading now from your report, discussion you have 
	underneath this cartoon.  Last line:  "The 1990 report was 
	not predicated on global warming scenario.  It is clear at 
	least in 1990 the medieval warm period was thought to have 
	temperatures considerably warmer than the present era."  Is
	that your discussion?
	DR. WEGMAN.  Yes.
	MR. STUPAK.  So we should not believe that statement then?
	DR. WEGMAN.  No, I said--I didn't say I believed it was.  I
	said they believed it was.  The IPCC gave that report in 1990.
	MR. STUPAK.  All right.  This chart--
	DR. WEGMAN.  I didn't--
	MR. STUPAK.  This is in your executive summary, right, page 34, 
	and what I read was correct?
	DR. WEGMAN.  Yes.
	MR. STUPAK.  Okay.  Let me ask you this question.  Have you 
	reviewed any of Mr. Mann's later refinements of his 1999 
	report?
	DR. WEGMAN.  I have reviewed some level of detail, not in 
	intense level of detail, the continuing papers, most of which 
	are referenced--in fact, the ones that are referenced--
	MR. STUPAK.  Did he refine his data and his methodology?
	DR. WEGMAN.  My take on the situation is that rather than accept 
	the criticism that was leveled, he rallied the wagons around 
	and tried to defend this incorrect methodology.
	MR. STUPAK.  But did he refine his methods in later studies 
	that he conducted, not whether he rallied the troops?  Did 
	he refine his methods?  Was his job more accurate as he went 
	on with later reports?
	DR. WEGMAN.  I believe that he does not acknowledge his 
	fundamental mistake and that he has developed additional 
	papers with himself and his colleagues that try and defend 
	the original hockey stick shape.
	MR. STUPAK.  Do you know that or are you just guessing?
	DR. WEGMAN.  I am guessing that.
	MR. STUPAK.  Okay.  Statisticians, should they guess or 
	should they have facts to--
	DR. WEGMAN.  That is called statistical estimation, yes.
	MR. STUPAK.  I see.  Or a cartoon.
	DR. WEGMAN.  The cartoon is IPCC's cartoon, not mine.
	MR. STUPAK.  You relied upon it though in your executive 
	summary.  So I am looking at the cartoon.  There is no 
	data, is there, to say that around 1300 it warmer than it 
	is in the latter half of--
	DR. WEGMAN.  I think that is an inaccurate statement.  I think 
	there is data.  I think the data--
	MR. STUPAK.  Do you have any of it?  Can you show us where any 
	of that is?
	DR. WEGMAN.  No, I don't have it.  I take no responsibility for 
	what IPCC did in 1990.  There is no way I could do that.  Their 
	data is not available to me.  In fact, the reason it was 
	digitized was that I had to go back and construct it from their
	picture.  That doesn't mean no data exist.  And in fact, as far 
	as I know, it was based on European and Asian temperature 
	profiles that were available in the 1990s.
	MR. STUPAK.  Sure, and in that, it was thought--it was still not 
	clear that all the fluctuations indicated were truly global.  
	In fact, I think some of the testimony earlier said that parts 
	of western Europe, China, Japan, and eastern U.S.A. were a few
	degrees warmer in July than other parts of the world.  Parts of
	Australia, Chile, and I think Greenland were actually cooler, 
	they said, and China was actually colder than at any other time.
	DR. WEGMAN.  Yes, I don't dispute that.
	MR. WHITFIELD.  The gentleman's time has expired.  I recognize 
	Mr. Bass.
	MR. BASS.  And I thank the gentleman for recognizing me.  Before 
	I start my questions, I just want to mention that there is a
	considerable amount of climate change work going underway in 
	New Hampshire, my home state of New Hampshire, the Cold Research
	Laboratory which is run by the Army Corps of Engineers.  They
	are studying ice core samples from both the Arctic and the 
	Antarctic icecaps and also at the University of New Hampshire.  
	NOAA, National Oceanographic and Atmospheric Administration is 
	conducting ongoing longitudinal studies on the North Atlantic, 
	air, water temperatures.  And thirdly, at Hubbard Brook which 
	is another research lab, they are studying climate change 
	effect on trees and plants and other organic matter.
	CHAIRMAN BARTON.  Could the gentleman yield while--
	MR. BASS.  Yes.  Sure.
	CHAIRMAN BARTON.  Dr. North, Mr. Stupak just went to some 
	lengths discussing this chart on page 34 of Dr. Wegman's report 
	that is from the IPCC assessment report of 1990.  Can you tell 
	us what the IPCC assessment report of 1990 was?
	DR. NORTH.  The IPCC is the Intergovernmental Panel on Climate 
	Change.  It is under the auspices of the United Nations and I 
	don't know the network all the way down to this group but this 
	is a group that meets and is tasked to come up with a report 
	every 5 years approximately.
	CHAIRMAN BARTON.  But in layman's terms, could we say that 
	the IPPC--
	DR. NORTH.  No, IPCC.
	CHAIRMAN BARTON.  IPCC is the technical working group for 
	the United Nations council of parties that ultimately 
	drafted the Kyoto Accords?
	DR. NORTH.  I don't know if there is a connection. I just 
	don't know that.  I am sorry.
	CHAIRMAN BARTON.  It is my understanding that the IPCC is 
	the group that prepared all the analytical materials and 
	forwarded them on--
	DR. NORTH.  They may have used their information.  The 
	IPCC, their job is to provide assessments, so Congress, 
	political bodies go to them and ask for an assessment of 
	the state of the art or the state of the science at the 
	particular time as it is seen at that time.  Of course, it 
	changes so they came out again in 1995 and again in 2000 
	and there will soon be another one issued.
	CHAIRMAN BARTON.  But in 1990 when these scientists produced 
	that report, this was their assessment of temperatures between 
	the year 1000 and the mid-1950s?
	DR. NORTH.  That is what they thought at that time.
	CHAIRMAN BARTON.  It doesn't mean they were right, it doesn't 
	mean that they haven't changed their mind.
	DR. NORTH.  That is why--
	CHAIRMAN BARTON.  But in 1990 the state of the art was, 
	that is what--
	DR. NORTH.  That is what they thought.
	CHAIRMAN BARTON.  That is what it was.  I yield back.
	MR. BASS.  Thank you, Mr. Chairman.  Dr. Karl is going to 
	follow you in the second panel and I will read a sentence out 
	of his testimony and ask you a question about it, the last 
	page.  "At the present time there is no formal process whereby 
	federally funded scientists must submit their data to a 
	long-term data archive facility for use by others.  The 
	submission of data to institutions like NOAA's, national 
	climatic data center, the world's paleoclimatic data center, 
	requires significant investment of time by the principal 
	investigators who collected the data to provide the useful 
	information about the proxy data to the receiving data center.  
	In addition, if such data are submitted, a significant 
	investment by the data center would need to be made to ensure 
	that the data is usable by others in perpetuity and safeguards 
	for future generations," and then he goes on about 
	discussions.  Dr. North, do you think this is an appropriate 
	priority, and if so, do you think it would require any 
	legislative action?  What are your observations about Dr. 
	Karl?  And I think Dr. Wegman made the same contention.  How 
	do you feel about it, Dr. North?
	DR. NORTH.  Before I say anything, I should say that I know 
	Dr. Karl and I have actually collaborated with him on some 
	things, so that is a fact.  I visited his laboratory, his 
	center in Asheville, which is a very nice operation there.  
	So I do think it is a good idea.  I think it is something 
	that the Government through a national laboratory like his 
	should take on.  I think this is too much for the little 
	principal investigator out at your university or mine to 
	deal with.  So this is a way that data like this can be 
	archived in a nice, clean environment.  At Texas A&M, for 
	example, we have the ocean drilling program and so we store 
	these cores there that have been dug and they are carefully
	archived and protected and so I think that different 
	laboratories should be charged with that kind of duty instead
	of having every little PI's home base, so I do think it is a 
	good idea.
	CHAIRMAN BARTON.  Would the gentleman yield on that?
	MR. BASS.  Certainly.
	CHAIRMAN BARTON.  I just think the record should show that 
	when I was Congressman for Texas A&M, I helped get the money 
	to establish that program and I am responsible for some of 
	those core samples.
	DR. NORTH.  And I work with some of those people--
	CHAIRMAN BARTON.  I want the record to show that.
	MR. BASS.  Reclaiming my time.  I might suggest that this 
	concept might be a starting point for some bipartisan 
	cooperation legislatively if necessary to achieve this 
	objective which would move the issue forward.  Dr. Wegman, 
	there has been some discussion about the network issues 
	associated with paleoclimatologists.  Is it substantially 
	different than--you know, the incestuous nature of the 
	relationships between the paleoclimatologists.  Do you think 
	that it is the same or is different from other academic 
	subjects?
	DR. WEGMAN.  I don't know all of the academic subjects.  What 
	is true, I believe, is that in less focused activities, 
	there are probably more competing social networks which
	even the playing field a little bit more than it appears 
	to be in the paleoclimatology area.  As mentioned earlier, 
	I think for one person to have 43 coauthors is an unusually 
	large number of coauthors.  I personally believe that I 
	probably have maybe 15 people that I have worked with over 
	the years.
	MR. BASS.  Fair enough.  Would you take--is it appropriate 
	to take into account in that analysis the size of the 
	entire climatic science community or is paleoclimatology 
	so specialized that you couldn't?
	DR. WEGMAN.  Yes.  I think one of the interesting things 
	that we will probably hear later on is the notion that 
	this paleoclimatology is really an interdisciplinary area 
	so it involves dendrology, it involves people that work 
	with trees, with ice cores and so on and so forth.  So it 
	is not totally insular in the sense that it doesn't 
	involve people from other parts of this arena.  What is 
	insular though I think is that it doesn't really involve 
	people from the areas that I call the enabling sciences 
	such as mathematics, computer science, and so on.  But I 
	think if you sort of followed the second order, third 
	order, fourth order links, you would probably get a more 
	interesting social network as well.
	MR. BASS.  One last question, Dr. Wegman.  The National 
	Academy of Science report that was released last month 
	states the following:  "It can be said with a high level 
	of confidence that the global mean surface temperature 
	was higher during the last few decades of the 20th Century 
	than during any comparable"--during, I don't know, there 
	must be a typo here-"during the preceding four centuries."  
	Now, I understand from your testimony on the first page 
	that you want to distance yourself from the issue of 
	global warming, its causes, and its solutions, but would 
	you agree with that statement?
	DR. WEGMAN.  Yes.  I think that is a reasonably cautious 
	verifiable statement that in terms of--and I speak now not 
	as a professional statistician but as a citizen of this 
	country.  It seems to me that it is entirely reasonable to 
	say that Dr. North and his panel made an accurate 
	assessment, but it must be understood in the context which 
	is that we have relatively speaking a Little Ice Age, 
	which everybody seems to acknowledge, and so it is not so 
	surprising that it is warming if we are coming out of a 
	Little Ice Age.
	MR. BASS.  I want to thank both of you gentlemen for your 
	testimony today and I yield back.
	MR. WALDEN.  [Presiding]  The gentleman yields back his 
	time.  The gentlelady from Illinois, Ms. Schakowsky, is 
	recognized for 10 minutes.
	MS. SCHAKOWSKY.  Thank you, Mr. Chairman.  I have so 
	many things I want to ask here.  Let me start again.  
	Dr. North, I want to confirm what I think you already said. 
	Is Dr. Mann's hockey stick study considered to be the 
	foundation on which all climate change science is based?
	DR. NORTH.  No.
	MS. SCHAKOWSKY.  It isn't.  And again I want to say, if 
	it never were, if the study simply--the hockey stick, the 
	original and there was a revised in 2003-2004, right, my 
	understanding is, which I guess you disagree, Dr. Wegman, 
	acknowledged some of the mistakes and made some changes 
	but if it never did, would most scientists essentially
	arrive at the same conclusion as we are seeing, that we
	are engaged--that this is a time of global warming 
	attributable in large part to human activity?
	DR. NORTH.  Yes, I think that is true.
	DR. WEGMAN.  By the way, for what it is worth, I think it 
	is true although I would caution you to not say most 
	scientists.  Most climate scientists would probably--
	DR. NORTH.  That is better.  Thank you.  I appreciate 
	that.
	MS. SCHAKOWSKY.  Okay, most climate scientists.  Should we 
	not rely on climate scientists for our information about 
	the climate?
	DR. WEGMAN.  The point I was making was that you are saying 
	most scientists, so the testimony--
	MS. SCHAKOWSKY.  Well, let me ask--
	DR. WEGMAN.  --of a chemist is irrelevant to--
	MS. SCHAKOWSKY.  Exactly.  So would you agree then that 
	climate scientists are those that we should primarily refer 
	to when we are asking questions about climate?
	DR. WEGMAN.  Certainly.
	MS. SCHAKOWSKY.  So you would agree that human activities 
	are not only increasing atmosphere greenhouse gases but that 
	it is attribute would you say in large part mostly in terms 
	of your understanding as not a climate scientist to human 
	activity?
	DR. WEGMAN.  I am in no position to say--
	MS. SCHAKOWSKY.  Well, what did you say you did agree with 
	earlier?
	DR. WEGMAN.  I said I agree that it is warming.  That is what 
	I agreed to.  I mean, I said it several times now that the 
	temperature record from 1850 onwards indicate that it is 
	warming.
	MS. SCHAKOWSKY.  I also had said earlier that in my question
	to Dr. North and that most scientists agree that in large 
	part or for your purposes I will say in some part 
	attributable to human activity.  Would you agree with that?
	DR. WEGMAN.  I don't know that for a fact.
	MS. SCHAKOWSKY.  Okay.  You don't know that.
	DR. WEGMAN.  Again, it is the connection between carbon 
	dioxide and temperature increase.  Now, Mr. Inslee pointed 
	out that he thinks there is a physical explanation based 
	on a blanket of carbon dioxide in the reflection.  Carbon 
	dioxide is heavier than air.  Where it sits in the 
	atmospheric profile, I don't know.  I am not an atmospheric 
	scientist to know that but presumably if the atmospheric--
	if the carbon dioxide is close to the surface of the Earth, 
	it is not reflecting a lot of infrared back.
	MS. SCHAKOWSKY.  Okay.  But are you not really qualified 
	to--
	DR. WEGMAN.  No, of course not.
	MS. SCHAKOWSKY.  --comment on that.  I think since we are 
	talking about scientific data, statistics, let us be clear, 
	and you are challenging a report which form what I 
	understand as Dr. North in some part at least you agree 
	with the critique of the Mann data, so--and I am certainly--
	I am neither, but we are policymakers here so what I--do you 
	believe that your report disproves that climate change is 
	manmade in any way?
	DR. WEGMAN.  No.
	MS. SCHAKOWSKY.  And since you think that you are not in a 
	position to make a decision on global warming, are you 
	uncomfortable at all, Dr. Wegman, that the consequences of 
	what you are saying today to policymakers, I think most of 
	whom, if not all of them, are neither statisticians or climate
	scientists, could have the impact of saying we don't need to 
	do anything.  Does that make you uncomfortable at all?
	DR. WEGMAN.  I would hope that our legislators are smarter 
	than that to know that when somebody says that they are using 
	wrong methodology, that does not imply that some fact is not 
	true.  I would hope that you would take my testimony with the 
	idea that if something is wrong with this piece of work, it 
	ought to be discarded as a policy tool, and that is precisely 
	what I am saying.
	MS. SCHAKOWSKY.  Well, let me ask you this.  Dr. Mann has
	published dozens of study since the original hockey stick 
	study and as I said earlier, beginning in 2003 he reformulated 
	the statistical methods.  Do you take into account these later 
	studies in your report?
	DR. WEGMAN.  I have read his later studies. I was not asked 
	about his later studies.  I think as science iterates, things 
	do get better, but as I indicated before, one of the 
	unfortunate aspects of this overall situation with Dr. Mann 
	and his colleagues, my attack is not an attack at all.  It 
	is simply trying to lay out what I perceive to be a true 
	statement.  I think it is unfortunate that rather than moving
	on and saying gosh, I made a mistake and here is the better
	situation, here is a better approach, there continues to be 
	a defense which is captured in his web log called 
	realclimate.org.
	MS. SCHAKOWSKY.  And I understand that there are these 
	battles and sort of the academic politics and scientific 
	politics, et cetera, but do you disagree with Dr. North that 
	even without Dr. Mann altogether or are you using these 
	social--what do you call it--to say that everything now has 
	to be discredited?
	DR. WEGMAN.  No, I don't think everything at all has to be 
	discredited, and I think the things that do not use the 
	techniques, the flawed methodology with respect to principal 
	components, anything that doesn't use those, I have no 
	position on.
	MS. SCHAKOWSKY.  And you talked about the cartoon that was 
	in the Wall Street Journal article and then my understanding 
	that the graph or whatever you call this, this drawing that 
	it in your report, is it not true that it ends in 1975?
	DR. WEGMAN.  I think that is approximately accurate.  But
	again, I--this also appears in the National Academy report
	as well as the Wall Street Journal.  I did not have the
	original data for that cartoon, for that graph, and so I had 
	no way of knowing what the full range of the time frame was 
	for that.
	MS. SCHAKOWSKY.  And would you confirm that, Dr. North, that
	it goes approximately or maybe exactly to 1975?
	DR. NORTH.  It is 1975.  That is correct.
	MS. SCHAKOWSKY.  I am trying very hard to understand the 
	point of this hearing and this conflict because if we are 
	through many studies come to the conclusion that there is 
	such a thing is global warming, which is hard to deny on a 
	day like today and yesterday, et cetera, although I am not 
	the scientist, and that it at least in some part is caused 
	by human activity, then why we are doing this really does 
	escape me.  I can understand why in academia you may have 
	an interest in discrediting Mann and back and forth, but I 
	am very concerned that this is being used in a way to 
	discredit the whole notion that our country and the rest of
	the industrialized and developing ought to do anything 
	about global warming, and that is why I asked you that 
	question, Dr. Wegman, if this does not make you somewhat 
	uncomfortable.  Can you see in any way how this is being 
	used and does it bother you?
	DR. WEGMAN.  Well, I can understand that it is your job to 
	sort out the political ramifications of what I have said.  
	In some sense it is not fair for you to say well, gee, you 
	have reported on some fact and that is going to be used in 
	a bad way.  The other side of the coin is that, you have 
	tried to get me to say that manmade carbon dioxide emissions
	are associated with the global warming.
	MS. SCHAKOWSKY.  Which you can't, right, because you are not
	a climate scientist.
	DR. WEGMAN.  I cannot say that, but what I can say is that 
	from 1850 to the present time, the global temperature rise 
	is about 1.2 degrees Centigrade according to the Mann chart. 
	One point two degrees Centigrade translates to about two 
	degrees Fahrenheit.  I challenge anybody to go out and tell 
	the difference between 72 and 74 degrees Fahrenheit.  What 
	I do say and what I have said repeatedly is that you need 
	to focus on the basic science.  You need to understand what
	the transfer of heat from the ocean to the atmosphere, how 
	that dynamic works, how the climate is going to change 
	based on the physical mechanisms, a fundamental understanding
	of the physical mechanisms, not on some statistical 
	estimation of those signals.
	MR. WALDEN.  The gentlelady's time has expired.  The gentleman
	from Florida, Mr. Stearns, for 10.
	MR. STEARNS.  I thank you, Mr. Chairman.  Let me thank both of 
	you for your patience here and how long you have been sitting. 
	We have been changing chairmen here.  They get to go but you 
	don't so we are very appreciative of what you are doing here.  
	I think you aptly replied to Ms. Schakowsky's comment that 
	basically we are trying to look at the science of this.  
	Mr. Chairman, I think it would be appropriate to put by 
	unanimous consent this Wall Street Journal article, if you 
	don't mind to put this in.  It is--
	MR. WALDEN.  Without objection.
	[The information follows:] 

	MR. STEARNS.  Thank you.  It talked about the hockey stick 
	hokum and it goes on to talk a little bit about Mr. Mann and 
	we all talked about it all morning but it says in 2001 the 
	IPCC replaced the first graph with a second in its third 
	report on climate change and since then this graph has cropped
	up all over the place.  In fact, I think it is in Vice 
	President Gore's movie and I believe it is in his book, 
	"Inconvenient Truth."  On page 65 he has got the source as 
	the IPCC and then a little bit above it he talks about the 
	hockey stick, a graphic image representing the research of 
	climate scientist Michael Mann and his colleagues.  So I
	would just say to my colleagues and Ms. Schakowsky to that it 
	is important that if a graph suddenly becomes a significant 
	graph in all these publications and shows up everywhere and 
	is used in debate to make argument, I think it is important 
	for all of us to look at this graph and I think that is all 
	Dr. Wegman is doing is to say we are looking at this graph 
	and as it turns out in this book, "An Inconvenient Truth" by 
	Vice President Gore that he is using a graph as I understand
	it that has been established this morning that the 
	methodology and the statistical analysis of it is incorrect 
	and--
	MS. SCHAKOWSKY.  No, that is not--will the gentleman yield 
	for a second?
	MR. STEARNS.  Well, let me ask--
	MS. SCHAKOWSKY.  Just for one second.
	MR. WALDEN.  Just regular order.
	MR. STEARNS.  I will be glad to do that.  Let me just ask 
	Dr. Wegman, if I have in his book the reference to the 
	hockey stick and I have reference to the IPCC, then we have
	here a graph that you in fact are disputing because of its 
	methodology and the statistics.  Would that be a fair 
	statement?
	DR. WEGMAN.  Well, I would like to be careful in that 
	regard.
	MR. STEARNS.  Sure.  I know.  Do you want me to bring the
	book down and have the staff bring the book to you?
	DR. WEGMAN.  I have one.
	MR. STEARNS.  Oh, you have it.
	MS. SCHAKOWSKY.  Would the gentleman yield--
	MR. STUPAK.  Would the gentleman yield on that point 
	then?
	MR. STEARNS.  Well, let me just finish with my question 
	here because what I am trying to understand is, you have
	a graph that suddenly goes everywhere and we have 
	established today that the methodology for Dr. Mann's graph 
	is questionable, so the question is, if it shows up 
	everywhere, shouldn't the American people understand that 
	some of the reference here in the book, the methodology is
	in question?  That is all I am asking.
	MR. STUPAK.  Would the gentleman yield on that point?
	MR. STEARNS.  Well, let me ask--
	MR. STUPAK.  Because if you are going to ask the 
	question--
	MR. WALDEN.  Regular order, please.  It is the gentleman's 
	time--
	MR. STEARNS.  I am not asking the question to you.  I am
	asking it to Dr. Wegman, so I think, Mr. Chairman, I would 
	like to have the question asked to him and not to my fellow
	colleagues.
	DR. WEGMAN.  Let me be precise on the statement.  There is
	some ambiguity in this book because it talks about ice 
	cores and as I understand it, this particular--
	MR. STEARNS.  This is on page 65.
	DR. WEGMAN.  This particular picture--
	MR. STEARNS.  Yeah, that is right, the same one.
	DR. WEGMAN.  --was based on ice core studies--
	MR. STEARNS.  But it says below, it says source, IPCC, at
	the very little, small little note there.
	DR. WEGMAN.  Right.
	MR. STEARNS.  Okay.
	DR. WEGMAN.  Higher on the same page in the text it talks 
	about Mann but I believe if one is going to be precise, 
	this is a piece of study based on ice cores, not on the 
	temperature reconstruction.
	MR. STEARNS.  So we just don't know, and I think that is 
	accurate.  I am glad you pointed that out so that the reader 
	or anybody looking at this would not necessarily say that the
	source of the IPCC is indeed Dr. Mann's hockey stick--
	MS. SCHAKOWSKY.  Would the gentleman yield for just a minute?
	MR. STEARNS.  No, I am just asking Dr. Wegman--
	MS. SCHAKOWSKY.  Please, I can read from--I am looking at the 
	same--
	MR. STEARNS.  You folks had your time.  I am just--
	MR. WALDEN.  Regular order.
	MR. STEARNS.  When I complete my thing.  So the question is, 
	he says IPCC here and he has got this graph that looks like a 
	hockey stick, you are saying that you cannot correlate that to
	mean that it is Dr. Mann's graph?  That is what you are saying?
	DR. WEGMAN.  I believe that is true.
	MR. STEARNS.  Okay.  All right.  Yes, I will be glad to yield 
	to Ms. Schakowsky.
	MS. SCHAKOWSKY.  Thank you.  I just want to read to you from 
	that same--it says "But as Dr. Thompson's thermometer show," 
	and so it is not based on Dr. Mann.  This is a different source
	which our staff had confirmed with Al Gore.  I just want to 
	make--
	MR. STEARNS.  I respect that.
	MS. SCHAKOWSKY.  --that point.  I know, but your question wanted
	to reinforce the notion that this was based on this false or 
	inaccurate Dr. Mann study--
	MR. STEARNS.  Well, I think--
	MS. SCHAKOWSKY.  --and it is not.
	MR. STEARNS.  Okay.
	DR. WEGMAN.  And I responded that it was not.
	MS. SCHAKOWSKY.  No, I--
	MR. STEARNS.  Go ahead.  You respond to that.
	DR. WEGMAN.  I responded exactly the same way you just did.
	MR. STEARNS.  And I think that is important to realize because 
	it is showing up not just here but it is showing everywhere 
	and so it is not precise that that is Dr. Mann's graph here, 
	and that is what you have confirmed.  Now, I think the other 
	real big question that we sometimes forget is, what effect does 
	this have?  I mean, what is--you mentioned here that it could
	be two degrees Fahrenheit from 1850 to 2006 and you say how 
	many people could know the difference between 72 degrees and 
	74.  That was your words.  The Competitive Enterprise Institute
	put out a report and let me just read from that.  Dr. James 
	Hanson of NASA, the father of the greenhouse theory, and 
	Richard Linzen of MIT, both of them are renowned climatologists
	in the world, agree that if nothing is done to restrict 
	greenhouse gases, the world will see a global temperature 
	increase of about one degree Centigrade in the next 50 to 100
	years.  Hanson and his colleagues predict additional warming 
	in the next 50 years of .5 degrees Centigrade.  A warming rate
	of .1, tenth of a percent Centigrade per decade, does that 
	seem like an accurate statistic to you?  Would you generally 
	agree with that or disagree?  I know it is difficult but--
	DR. WEGMAN.  I have no way of truly knowing.
	MR. STEARNS.  But I mean, if you say in the last 156 years we 
	have only had two degrees Fahrenheit, I mean, this would 
	confirm that this is not something that is out of control.  
	Wouldn't you say that basically--my point I am trying to 
	establish is, that the estimates of this future warming should 
	not get us into a hysterical mode.  I know--
	DR. WEGMAN.  I would tend to concur but what I would also say 
	is that the global average temperature is probably not a very
	good measure of global warming in the sense that, as I said
	before, ocean circulation, salinity, how the Gulf current 
	subducts when it gives up its heat in the Northern Hemisphere, 
	understanding the coupling of that to the atmosphere seems to 
	me to be the scientific issue at hand that really ought to be
	investigated more thoroughly.
	MR. STEARNS.  Also in this Competitive Enterprise Institute, 
	the question came up, and Mr. Waxman mentioned a whole group 
	of scientists, renowned scientists, that said that we are into
	a global warming and in this report it says, "What do 
	scientists agree on and they agree that global average 
	temperature is about .6 degrees Celsius or just over one degree
	Fahrenheit higher than it was a century ago.  Atmospheric 
	levels of carbon dioxide have risen by about 30 percent over 
	the 200 years and carbon dioxide like water vapor is a 
	greenhouse gas whose increase is likely to warm the Earth's
	atmosphere."  Is that generally you think accurate?
	DR. WEGMAN.  As far I know, yes.
	MR. STEARNS.  But is there in your opinion a scientific 
	consensus that global warming is real and bad for us?  Could 
	you say categorically, both you and Dr. North today, that 
	there is a scientific consensus and evidence that global warming
	is bad and we should be very concerned about it?  That is a 
	tough question, I know.
	DR. WEGMAN.  I believe there is a consensus that global 
	warming is real.  My friends in Finland think it is a great 
	thing.
	MR. STEARNS.  And your friends here in the United States 
	don't.  Would that be fair to say?
	DR. WEGMAN.  Well--
	MR. STEARNS.  I mean, that it is occurring but it is not as
	significant the people that are out there saying we have 
	got to do something tomorrow, we have got to do something, 
	do something.
	DR. WEGMAN.  I think it is probably less urgent than some 
	would have it be.
	MR. STEARNS.  Dr. North, I am going to give you a few 
	moments, unless you want to--you don't have to say anything.
	DR. NORTH.  Well, my feeling is that it is happening but I 
	don't do good or bad.
	MR. STEARNS.  Let me just conclude, Mr. Chairman, just by 
	saying that Dr. Wegman said that in the last 156 years it
	has gone up just about two degrees Fahrenheit and so I don't
	really think we are into a very, very serious concern that
	we all should be worried about getting overly hot tomorrow.
	MR. WALDEN.  The gentleman's time has expired.  The 
	gentlelady from Wisconsin, Ms. Baldwin, for 10 minutes.
	MS. BALDWIN.  Thank you, Mr. Chairman.  Dr. Wegman, your 
	report includes a social networking analysis of the 
	authorship in temperature reconstruction, and to your 
	knowledge, has this type of social network analysis ever 
	been done before to look at an academic field?
	DR. WEGMAN.  No, and in fact, based on reactions to this, I 
	think it is probably a good idea that we do this more 
	broadly.
	MS. BALDWIN.  And am I correct in understanding that your 
	analysis did not include talking to the paleoclimatologists 
	to get their perspective on how they interact nor did it 
	include substantively analyzing their interactions?
	DR. WEGMAN.  No.  We simply looked at their connection in 
	terms of, based on engineering compendics, based on their 
	coauthorship.
	MS. BALDWIN.  In your report, you state that, and I quote, 
	"Our findings from this analysis suggest authors in the 
	area of paleoclimate studies are closely connected and thus 
	independent studies may not be as independent as they might 
	appear on the surface."  Are you saying that based on your 
	social network analysis, that you are concluding that 
	independent studies may not be independent or are you saying
	that your network analysis suggests a lack of independence
	as a hypothesis that one would need to investigate further
	before one could draw a conclusion?
	DR. WEGMAN.  I think one should take our social network 
	analysis with a grain of salt to understand that this is an 
	unusual configuration of people with a highly central person 
	involved in this.  It is no surprise to any working scientist
	that there are groups of statisticians, groups of 
	mathematicians, groups of paleoclimate scientists, groups of
	physicists that work together closely and that there are 
	competing social networks.  I would hasten to add that social
	networks doesn't mean I go out and drink a beer with somebody. 
	It doesn't mean I am a buddy of theirs.  It means that I work
	with them, that I think like they do, that we have similar 
	approaches.  Now, if the group of people operating in this 
	area is relatively small, as I believe it is in the 
	paleoclimate area, then I think there is some evidence that
	probably should be investigated more clearly, that these
	people are refereeing their own papers.  After all, Michael
	Mann was an editor of the Journal of Climate and he
	publishes a lot of his papers in the Journal of Climate.  It 
	is pretty hard to say well, I am going to take this guy who 
	is well known and I am going to start rejecting his papers.  
	That is a pretty hard thing to do.
	MS. BALDWIN.  Well, Dr. Wegman, my question was, is this a
	hypothesis or is it a conclusion that you have drawn?  If 
	it is a hypothesis that would need to be investigated 
	further and of course earlier we heard Dr. North's response 
	to a question about what this--how fiercely competitive 
	people early in their scientific careers, late in their 
	scientific careers are.  I am a granddaughter and a niece of
	two researchers and I feel like I have had a lifelong sense 
	of how competitive these things, even if you have a very 
	narrow perspective.  But are you reaching a conclusion or 
	a hypothesis?
	DR. WEGMAN.  No, this is a hypothesis.
	MS. BALDWIN.  Okay.  Then if I understand you correctly,
	there are at least two problems with the Wall Street 
	Journal's statement in an editorial last week that your 
	"conclusion is that the coterie of the most frequently 
	published climatologists is so insular and so close-knit 
	that no effective independent review of the work of 
	Mr. Mann is likely," because first your social network 
	analysis wasn't of climatologists but a much narrower 
	group of temperature reconstructionists, and second,
	your social network analysis did not allow you to reach 
	a conclusion about the independence of review of 
	Dr. Mann's work.
	DR. WEGMAN.  I think that there is--you know, in some 
	sense you are putting words in my mouth but I think 
	there is evidence--
	MS. BALDWIN.  Well, the Wall Street Journal--
	DR. WEGMAN.  Let me finish.  I think there is evidence
	based on this social network analysis, based on the real 
	climate.org web log, based on the general reaction of 
	Dr. Mann and, for that matter, Dr. Bradley and Dr. Hughes
	to the initial inquiries to the committee that there is a
	tight-knit group of people who are interacting with each 
	other and who frankly don't seem to like to be criticized.
	MS. BALDWIN.  Dr. Wegman, I have an additional question.  
	I think it has been touched on before but I just want to 
	get some real clarity on this.  I understand that the data 
	that you used is based on Mann's 1998 and 1999 studies.  
	In the recent years Dr. Mann has altered his 
	reconstructions using different methods and proxies.  Each
	time he has been able to reach virtually the same 
	conclusions.  Did you analyze any data from Mann's later 
	studies or those from other reputable climate scientists 
	who have reached similar conclusions?
	DR. WEGMAN.  We did not attempt to reproduce any of the 
	later material.  However, what we did do was look at the
	proxies that were used and we looked at the series of 
	papers beginning actually with Jones and Bradley, I think
	it was, in 1993 and compared the proxies that they were
	using and the methodologies that they were using.  
	Basically Mann articulates I believe in his 2005 paper 
	the set of papers that used the climate field 
	reconstruction, the CFR methodology, and also uses the
	CPS methodology.  Those are articulated by Mann, not by 
	me.
	MS. BALDWIN.  But you used the 1998 and 1999 studies?
	DR. WEGMAN.  We were asked to address the issues in 1998
	and 1999, yes.
	MS. BALDWIN.  I would now yield my remaining time to 
	Mr. Inslee, who requested that.
	MR. INSLEE.  Thank you.  Doctor, I have been trying to figure
	out how to characterize the situation, and the best I can do 
	is to say that we don't debate gravity anymore and we should
	not debate whether there is a human contribution to global 
	warming anymore, and the way I look at this is sort of like 
	if you had reviewed Newton's Principia where he laid out the 
	basic laws of physics that we have now based, until quantum 
	mechanics came around, most of our science, if you found a 
	statistical flaw, which I will bet you could if you looked 
	at the whole Principia that didn't meet sort of regular 
	statistical proofs right now, you might come into Congress,
	if the Republicans controlled Congress in 1695, anyway, and 
	say, you know, I found this statistical flaw in this one 
	little piece of Newton's theory, even after we have a 
	mountain of evidence that gravity is a fact, not a theory,
	upon which we base our science, and that is the reason that
	you are not urging, as I understand it, us to reject 
	Dr. Mann and his group's conclusion, that humans are a 
	causative factor for global warming.  The reason you are 
	not asking us to reject that conclusion is that you 
	recognize that you have found what you believe is a 
	statistical flaw in one study but it does not contravene 
	the mountain of evidence that says global warming is 
	caused a not insignificant part by human activity.  Is 
	that a pretty fair metaphor for this?
	DR. WEGMAN.  Well, I--you know, the issue is, I was asked 
	a very specific question.  I came here to testify on a
	very specific question.  And you are asking me to testify 
	off of my level expertise and I--
	MR. INSLEE.  Well, let me just ask you--
	DR. WEGMAN.  --am not going to do that.
	MR. INSLEE.  Let me ask you a quick question.  If you 
	found a statistical flaw in the Principia published by 
	Sir Isaac Newton in 16 whenever it was, would you suggest
	that we reject the theory of gravity?
	DR. WEGMAN.  I would not suggest anything because that was
	not the question I was asked and that is not the reason I 
	am here.
	MR. INSLEE.  Well, unfortunately, this is the reason--
	DR. WEGMAN.  I mean, if you are asking me as an ordinary
	citizen--
	MR. INSLEE.  No, I want you to make sure you understand 
	the reality of the situation.  I am giving you all the 
	sincerity that I can give to you.  But the reason you are
	here is not why you think you are here, okay.  The reason 
	you are here is to try to win a debate with some industries
	in this country who are afraid to look forward to a new 
	energy future for this Nation, and the reason you are here 
	is to try to create doubt about whether this country should 
	move forward with a new technological clean energy future 
	or whether we should remain addicted to fossil fuels.  That
	is the reason you are here.  Now, that is not the reason 
	individually why you came but that is the reason you are 
	here.  Thank you very much.
	MR. WALDEN.  The gentleman's time has expired, which is
	the reason I am here to keep control of this.
	DR. WEGMAN.  But I didn't get to answer.
	MR. WALDEN.  Well, I will just give Dr. North a question. 
	Does anybody still study gravitational theory in the 
	scientific community?
	DR. NORTH.  Yes, they do.
	MR. WALDEN.  If you find--
	DR. NORTH.  It is a very active field in physics.
	MR. WALDEN.  Do you ever learn anything new?
	Dr. North.  Absolutely.  Things are being learned all 
	the time.
	MR. WALDEN.  And are you allowed then to publish new 
	findings that might contradict old findings?
	DR. NORTH.  Absolutely.
	MR. WALDEN.  Okay.  Good.  Science moves forward.  Now,
	I have to apologize.  I was in another markup earlier 
	and so I missed some of the questions and some of the 
	opening statements although I am familiar with both of 
	your gentlemen's testimony.  But I just want to make 
	sure I understand one sort of underlying piece, and
	that is, did you both indicate that Dr. Mann's 
	underlying statistical analysis was incorrect?  
	Dr. Wegman?
	DR. WEGMAN.  Yes.
	MR. WALDEN.  Dr. North?
	DR. NORTH.  Well, we found that it is not--there were 
	many choices to make.  They probably didn't make the best
	choice when they did the analysis the way they did.
	MR. WALDEN.  What do you when--
	DR. NORTH.  When their claims are wrong, it just means they 
	are not very convincing because of the way they did it.
	MR. WALDEN.  Okay.  Now, I am not a scientist so tell me--
	DR. NORTH.  That was nuanced.  I apologize.
	MR. WALDEN.  No, no.  Tell me what that means as a 
	layperson, as a lawmaker, when you say they made choices 
	in their--
	DR. NORTH.  Well, when you approach a problem like this, 
	there are many choices when you try to do a statistical 
	analysis and so there are many choices as to should you 
	deter in the data in the 20th Century or should you not.  
	Should you use this kind of validation procedure or a 
	different one.
	MR. WALDEN.  Right.
	DR. NORTH.  And in fact, one series of papers by Burger 
	and Cubasch actually looked at the situation and decided 
	there were 64 different ways you could have done it, and 
	had you chosen--and so they actually showed us a family of
	extrapolations you would have gotten using all of those 
	different--
	MR. WALDEN.  And did they all look like a hockey stick?
	DR. NORTH.  They all--well, I mean, to me they do.  But, 
	it is a bit curved.  It is not exactly like the hockey 
	stick but within the error bars, and by the way, in the 
	Wall Street Journal article, there is really a mistake 
	made in that graphic, and that has to do with the error 
	bars.  It does show--these two graphics are in our 
	reports, the same ones that are in the Wall Street 
	Journal report, and if you look at the Wall Street Journal
	article, they don't put the margin of error in there, which
	is really important.
	MR. WALDEN.  What is the margin--
	DR. NORTH.  I mean, it is totally irresponsible to do this 
	without the margin of error.
	MR. WALDEN.  Okay.  Can I ask you, what should that be so 
	we clarify the record, the margin of error?
	DR. NORTH.  The margin of error is the plus-minus 95 percent
	confidence interval.
	MR. WALDEN.  And that is what it should have been here?
	DR. NORTH.  That is right.
	MR. WALDEN.  The plus or minus--
	DR. NORTH.  And so when you look at the family of curves, 
	they all fall pretty close to that gray area in this graphic 
	but in the Wall Street Journal article, the gray is removed.
	MR. WALDEN.  Now, in the Wall Street Journal article too, 
	they make a reference to a McIntyre and McKitrick critique, 
	and I guess, have you reviewed that one, Dr. North
	DR. NORTH.  Oh, I am familiar with their work and, in fact, 
	Mr. McIntyre is here.  He will be testifying later.
	MR. WALDEN.  Did he present to your panel?
	DR. NORTH.  Yes, he did.  And in fact--
	MR. WALDEN.  Can their data be replicated or the results 
	be replicated?
	DR. NORTH.  Well, what they did was a critical study, 
	somewhat like the Wegman report, and I think they did an 
	honest job.  It was a nice piece of work.
	MR. WALDEN.  Dr. Wegman--
	DR. NORTH.  I have no complaint about what they did.
	MR. WALDEN.  In terms of replicating data or replicating
	studies, my understanding is, it is difficult to replicate 
	the Mann study but it was possible to replicate the 
	McIntyre and McKitrick study.
	DR. WEGMAN.  Yes, that is correct, and we did so.
	MR. WALDEN.  I want to move on to a little different topic
	and that is related to data sharing because I have run into
	this in another committee where I am a subcommittee chair
	on science and that was, there was a dispute--imagine that--
	over a report that was run out and published and somebody 
	else tried to get the data to see if they could replicate it 
	and there was a long delay and it was a real problem, and I 
	know Dr. North, in your report, you say--page 112 of the 
	surface temperature reconstructions the past 2,000 years, 
	you make a comment that says, "Our view is that all research
	benefits from full and open access to published data sets 
	and the clear explanation of analytical methods is mandatory. 
	Peers should have access to the information needed to 
	reproduce published results so that increased confidence in 
	the outcome of the study can be generated inside and outside 
	the scientific community," and you make that comment.  Then 
	I note--
	DR. NORTH.  I was about to read it to you.
	MR. WALDEN.  What is that?
	Dr. North.  I was about to read it to you.
	MR. WALDEN.  Well, we can do it in the key of C next time 
	together.  Then Dr. Wegman, on page 4 of your testimony, 
	you say, "Additionally, we judge that sharing research
	materials, data, and results was haphazardly and grudgingly 
	done," and further I believe it on page 66, there is a 
	reference--there is a question, "Has the information needed
	to replicate their work been available, and the answer is, 
	in our opinion, no.  As mentioned earlier, there were gaps 
	in MBH98."  Do we have a situation here where it was very 
	difficult to get the data to do replication, and if so, 
	why, do you think?
	DR. WEGMAN.  As I mentioned earlier, we did download the 
	data.  We have seen the letter that Dr. Mann replied to the
	committee which basically took the position that this is my 
	intellectual property and I don't have to share it and the
	National Science Foundation tells me so.
	MR. WALDEN.  Is that the case, Dr. North?  Do you speak for 
	the National Academy of Science?
	Dr. North.  No, no.
	DR. WEGMAN.  But the issue is that if there is free and open 
	access to the data and the materials that are associated 
	with the data, it makes the policing of this kind of 
	activity, the referees for the hockey game as I said earlier, 
	it makes it so much easier to be able to do that, and we 
	think that that is an important aspect of the scientific 
	enterprise.
	MR. WALDEN.  How do statisticians do these sorts of 
	evaluations?  Do you share data among yourselves?
	DR. WEGMAN.  Typically in terms of computer code, there are 
	two places that people typically go to.  There is an 
	electronic journal called the Journal of Statistical 
	Software which is a refereed journal.  People submit their
	code to that journal.  There is also a website that people 
	submit both data and code to.
	MR. WALDEN.  I don't know if you have had a chance to see 
	Mr. Crowley's testimony whom we will hear from later today
	but he has some rather unflattering statements about your 
	report.  I know it is shocking that different scientists 
	have different views of different scientists and their 
	reports.  He says that there are a number of flaws in your
	report and goes on to list some.  Do you have any comment 
	on the testimony we are going to hear later since you 
	won't be back at--
	DR. WEGMAN.  Well, I probably will be here but not sworn
	in or at least--
	MR. WALDEN.  Right.  You will still be under oath, they 
	inform me.
	DR. WEGMAN.  I understand where Dr. Crowley is coming 
	from.  He is in a relatively awkward position of having 
	to defend the position that Dr. Mann had taken.
	MR. WALDEN.  Why?  Why is that an awkward position?
	DR. WEGMAN.  Well, because you have heard from both of
	us this morning that there are fundamental flaws in the 
	Mann work and to come and have to defend that is an 
	awkward situation, I think.  Frankly, I would not have wanted 
	to get the letter that Dr. Mann got and the other coauthors 
	because that is kind of not on the radar screen of typical 
	scientists.  You know, you write a paper and you have a 
	file somewhere and right now my dean is telling me that we 
	should throw everything that is more than 3 years old, we 
	shouldn't keep it in the file drawers because we have space
	considerations, we have to keep space, but I--you know, I 
	think I jotted down the phrases he used about me which is 
	that I am naive and--I think it was naive and uninformed.  
	I don't think those are accurate statements because he has
	never talked to me either.  He has only read what we wrote
	and he has read it without the interaction with us as 
	statisticians so we will see what happens this afternoon.
	MR. WALDEN.  Is he a statistician, do you know?
	DR. WEGMAN.  Not that I know of.
	MR. WALDEN.  You made a comment about the potential 
	conflict with Dr. Mann being an editor of a journal and 
	also submitting work to that journal.
	DR. WEGMAN.  Yes.
	MR. WALDEN.  Do you know if he proofs his own work or does 
	he hold himself--
	DR. WEGMAN.  Generally the process is that an editor of a 
	journal will submit it, pass on the material to an associate 
	editor who will in turn select some referees.  That process 
	is typically what happens in a journal.  When I was editor 
	of a journal, I refrained from submitting anything to the 
	same journal that I was editor of simply because it puts
	pressure on the associate editors and referees to approve.
	MR. WALDEN.  Gentlemen, we appreciate your testimony and I 
	will go to the full committee Chairman, Mr. Barton.
	CHAIRMAN BARTON.  Well, I don't want to do a second round 
	because we have subjected these two gentlemen to close to--
	what is it--four hours of dialog.  I would want to--I want 
	to ask unanimous consent to ask Dr. North to comment on the 
	recommendations that Dr. Wegman gave and I also want to 
	renew my request that the Enders Robinson e-mail be put 
	into the official record.
	MR. STUPAK.  Mr. Chairman, as to the e-mail of Robinson, I 
	have no problem with that being entered in the record, but 
	if you are going to ask further follow-up questions, I know 
	there is one two further follow-up questions on this side 
	we would like to ask.
	[The information follows:]



	CHAIRMAN BARTON.  I am sorry.  I got the first part.  I 
	didn't get your second part.
	MR. STUPAK.  I said there are one or two follow-up 
	questions--
	CHAIRMAN BARTON.  Oh, you all have some follow-up?  Okay.  
	Could I be recognized then for 5 minutes?  Could we do the 
	second--
	MR. STUPAK.  No objection.
	CHAIRMAN BARTON.  Five minutes so that we can let this 
	panel go.
	MR. WALDEN.  The Chairman is recognized for 5 minutes.
	CHAIRMAN BARTON.  Thank you.  Dr. North, Dr. Wegman makes 
	four recommendations on page 6 of his testimony.  Do you 
	have that in front of you?
	DR. NORTH.  I think I have copied them out of there so I 
	think I have them here, yes.
	CHAIRMAN BARTON.  Could you comment on each recommendation, 
	whether you think his recommendations have merit?
	DR. NORTH.  Let--I will try to do that.  So recommendation 
	one was when massive amounts of public monies and so forth 
	are at stake, academic work should have more intense level 
	of scrutiny and review.  Well, nobody would argue with 
	that, of course.  It is especially the--we always want to 
	do things better.  It is especially the case that authors 
	of policy-related documents like IPCC and so forth should 
	be--
	CHAIRMAN BARTON.  He says the review should not be the same 
	people that constructed the academic paper.
	DR. NORTH.  So that is a really very interesting question and 
	subject.  You know, when you ask for an expert scientific 
	review of the state of art or the science and you go to the 
	world experts, and that is what the IPCC tries to, you will 
	find authors of the chapters who have also coauthored some of 
	the papers involved and indeed I think sometimes they do 
	promote their own work.  That is human nature.  We all know 
	how that works.  So that process isn't exactly perfect, but 
	I cannot imagine a better, more efficient way to pull 
	several thousand scientists together and they have to meet 
	repeatedly several times over the course of a year, over 
	the course of a couple of years.  One time we actually had 
	one of the meetings in College Station some years ago and 
	so people get tired of this.  It is really hard to work.  
	I mean, it sounds like it is fun but--
	CHAIRMAN BARTON.  To the largest extent possible, if you 
	can--
	DR. NORTH.  So it is very, very hard to--
	CHAIRMAN BARTON.  Sometimes there is not but two experts 
	in the world and so, you know--
	Dr. North.  That is right.
	CHAIRMAN BARTON.  But if it possible--
	Dr. North.  So, you know, you could go another way and 
	ask a situation like the academy did.  We had a small 
	committee of 12 people who were picked on the basis that 
	they were not connected with any of the--I mean, as 
	little as we could possibly do, connected with any of 
	the principals and the problem, so--
	CHAIRMAN BARTON.  But what about his recommendation 
	number two that there should be a more comprehensive and 
	concise policy on disclosure and that data collected under 
	Federal support should be made publicly available?
	DR. NORTH.  This is not a bad idea, and in fact, I think 
	Tom Karl is going to address that.
	CHAIRMAN BARTON.  And then his recommendation number three 
	is that if you are doing review and doing studies that 
	include some sort of a statistical approach on which your 
	conclusions are based, that there should be statistical 
	evaluation of the statistical practices.  He says it 
	should be a mandatory part of all grant applications.
	DR. NORTH.  I think that is a little over the top.  I 
	think--
	CHAIRMAN BARTON.  A little over--
	DR. NORTH.  I think carrying this to the Federal drug 
	approval process is--
	CHAIRMAN BARTON.  So you would--
	DR. NORTH.  It is not a good analogy.
	CHAIRMAN BARTON.  Well, what about his last one, that 
	emphasis should be placed on the Federal funding of 
	research related to fundamental understanding of the 
	mechanisms of climate change.  I think you would accept 
	that.  And that the funding should focus on 
	interdisciplinary teams and avoid narrowly focused 
	discipline research, and he is trying to broaden the 
	field so that it is not the same group of people talking 
	to the same group of people.
	DR. NORTH.  Well, it seems to me the two statements are 
	contradictory.  The first one says you should narrow the 
	field and the second one says you should broaden the 
	field, so, I mean--
	CHAIRMAN BARTON.  You are not real fired up about--
	DR. NORTH.  I want to see more money come into the field. 
	I think we all would like to see that.  That is great.  
	But I am not sure that one was very well formed out.
	CHAIRMAN BARTON.  Well, let me before I yield back my 52 
	seconds say why we are doing this hearing, because I have
	been here almost the entire time for every question and 
	every statement.  I missed a little bit but not much.  I 
	don't disagree fundamentally with some of what my friends 
	on the minority side have stated.  There is no question
	that the temperature is warmer today than it was in 1850.  
	I think there still is a question about the cause of that, 
	and some of these reports and studies that purport not 
	only to state the fact of the warming but the consequences 
	of it, I think should be open to honest public debate 
	without challenging the merits.  Where I disagree with 
	some of my friends on the minority side is that before 
	we make massive public policy changes that affect every 
	American citizen in this country, we need to have with 
	the highest degree of certainty that the facts really are 
	the facts.  Now, I have right here a magazine article from 
	Newsweek April 28, 1975, that is talking about the 
	cataclysmic consequences of global cooling.  Now, that is 
	30 years ago and the science has changed.  Now we are 
	talking about the cataclysmic consequences of global 
	warming.  If the United States has ratified Kyoto and if 
	the United States Congress working with the Administration 
	had begun to implement Kyoto, it requires a reduction in 
	CO2, I believe about 30 to 40 percent, and that means you
	are not going to have coal-fired power plant combustion 
	in many parts of this country.  It means that you are 
	going to have to reduce the automobile emissions of the 
	vehicles that are made in Michigan.  And before we go 
	down that trail, I think it is imperative that we do the 
	oversight and do the science and talk--I am not opposed 
	to talking to the climatologists but I agree with 
	Dr. Wegman that we need to make sure that it is an 
	interdisciplinary approach so that we really get everything 
	on the table.  If that shows that the human correlation is
	beyond dispute, then I believe we do have an obligation to
	take what steps we can to remedy that but I don't believe
	that science yet shows that.  With that I yield back, 
	Mr. Chairman.
	MR. WHITFIELD.  Thank you, Mr. Chairman.  At this time I 
	recognize Mr. Stupak for--
	MR. STUPAK.  Thank you, Mr. Chairman.  Chairman Barton, 
	and I take it, that means we are going to have a lot more
	hearings on global warming because there are a lot more 
	reports than just Dr. Mann's 1998-1999 report, so if we
	are going to come to those policy decisions, I would hope 
	we would have more than just one hearing about one report 
	and look at the whole spectrum of reports on global 
	warming.  Dr. North, if I may, the IPCC process, is that 
	based upon sound science, sound methodology?
	DR. NORTH.  In my opinion, when you go out and ask the 
	active scientists in the field to give you an assessment, 
	they select themselves and it has been my experience in 
	the three that have been produced that they do just that.  
	I had very little to do with the last one.  I served a 
	referee on--
	MR. STUPAK.  Sure.
	DR. NORTH.  But the one before, I had a little bit more 
	to do with it, but I think the process is pretty good. 
	You know, it is human.  It has some flaws in it but I 
	think I--it is probably the most massive assessment of 
	this kind that has ever been made.  It is remarkable
	that you get people to do that.  And I will tell you this, 
	people are tired of participating.  It is a lot of work.  
	Traveling to these countries and having these workshops 
	and meetings, it is a lot of work and so to actually ask 
	people who are not experts to come in and read all of 
	those papers that they weren't involved in, that is asking
	a lot of people and you won't get anybody to do it because 
	there is no money for this.  There is no pay for this.
	MR. STUPAK.  Okay.
	DR. NORTH.  Incidentally, the academy report people didn't 
	get paid anything either.
	MR. STUPAK.  Dr. North, you also mentioned the hockey stick
	hokum that was in the Wall Street Journal last Friday in 
	which they claimed that the graph from 1990 that we have 
	talked a lot about today showing the warming period in the
	Middle Ages, the Wall Street Journal goes on to say that in
	1990 the consensus "held that the medieval warm period was 
	considerably warmer than the present day."  It has been a 
	long hearing here today but is there any scientific 
	evidence from anyone that supports the claim that 
	temperatures in the Middle Ages were higher than they are 
	today?
	DR. NORTH.  There may be some locations on the Earth but so 
	why do we care about the global average?  You know, that 
	has come up a couple of times.  Because if CO2 is the 
	reason, it is a global forcing so you expect the response 
	to be at the global scale.  This is really important.  
	That is why--I mean, nobody takes a picnic at the global 
	scale but the scientists are very interested in what 
	happens to the global average because that is what is being
	forced by the CO2.  So that is why we are so fixated on the
	global average and getting large-scale averages.  It is 
	easier to measure it because when make measurements at a lot
	of locations, a lot of the random errors cancel out.  That
	is good.  The same thing happens with our models.  They do
	that better than anything else.
	MR. STUPAK.  Dr. Wegman, I thought I heard you say, and
	correct me if I am wrong, when you are making comparisons 
	you are saying that you used--I think it was figure 4 on 
	your chart--that you used North American factors in your 
	analysis with Dr. Mann's?
	DR. WEGMAN.  Dr. Mann himself used North American--what he
	called the North American PC1 proxy which was a composite 
	based on the principal of component methodology of North 
	American tree rings.
	MR. STUPAK.  Sure.
	DR. WEGMAN.  And that is what--we replicated that, yes.
	MR. STUPAK.  So in your analysis, you used just North 
	American, right?
	DR. WEGMAN.  We used the North America proxy.
	MR. STUPAK.  The P1, the P2--
	DR. WEGMAN.  The PC1--
	MR. STUPAK.  --and the P3?
	DR. WEGMAN.  Yes.
	MR. STUPAK.  PC.  I am sorry.  PC1, PC2.  But didn't really 
	Dr. Mann use 12 proxy indicators from all over the world?
	DR. WEGMAN.  We were not trying to do paleoclimate 
	reconstruction.  We were trying to illustrate what happened 
	if you did--
	MR. STUPAK.  Sure.
	DR. WEGMAN.  --the principal component--
	MR. STUPAK.  Dr. Mann used 12 proxies to come up with his 
	analysis.  You took three from North America.  Is it fair 
	to say then that using from throughout the world would have 
	a different result than if you just looked at the three in 
	North America?
	DR. WEGMAN.  Let us be clear.  He was doing Northern 
	Hemisphere, NH, reconstruction.  He wasn't doing global 
	reconstruction in--
	MR. STUPAK.  But if you take a look at his report, and I 
	know you did, they talk about Tasmania, taking tree rings 
	from there, Morocco, tree rings from there, France, the 
	Greenland stack core which we talked about, the ice core,
	polar Urals, again, the tree ring density.  It seemed to
	me he took them from all over the world where your focus
	is only on North America.  So how could you make the 
	comparison then when you use global statistics as opposed 
	to just one part of the world in doing your measurements?
	DR. WEGMAN.  Well, I am not sure I understand what you 
	are getting at.  The--
	MR. STUPAK.  From a layperson who is not a statistician, 
	I would think if you are going to compare Dr. Mann's 
	statistics, if you will, you would use all of them as 
	opposed to--
	DR. WEGMAN.  Our discussion--
	MR. STUPAK.  --just three of them.
	DR. WEGMAN.  Our discussion is on Dr. Mann's methodology, 
	not his conclusions in terms of paleoclimate--
	MR. STUPAK.  But you charted, did you not?  Didn't you 
	use X axis, Y axis and chart it all out and that is why 
	you got different than the hockey stick?  You only used
	three where he used 12.
	DR. WEGMAN.  No, no, no.  We used the same data to get the
	hockey stick in that one figure--
	MR. STUPAK.  From North America?
	DR. WEGMAN.  From North America.
	MR. STUPAK.  And he took his from the worldwide.
	DR. WEGMAN.  No, no, no.
	MR. STUPAK.  That is not what table one says.
	DR. WEGMAN.  What we said was that we used that comparison
	chart that we had that showed the hockey stick.  The 
	comparison was meant to show that if--
	MR. STUPAK.  Right here, yes?
	DR. WEGMAN.  That is it.  If you go to the top chart by 
	using his methodology on the same set of data and the
	bottom chart is what you would get if you did the centered 
	data, if you did it properly mathematically.  So the point--
	MR. STUPAK.  But yours is only on PC1, PC2--
	DR. WEGMAN.  So is his--
	MR. STUPAK.  --and PC3.
	DR. WEGMAN.  --in that picture.
	MR. STUPAK.  So you are saying that picture was only PC1, 
	PC2--
	DR. WEGMAN.  That is--
	MR. STUPAK.  --PC3 from Mann.
	DR. WEGMAN.  We are using exactly the same data in the top 
	picture and the bottom picture.
	MR. STUPAK.  Okay.  Thank you.
	MR. WHITFIELD.  The gentleman's time has expired.  Dr. North,
	in the testimony today, there seems to be universal agreement
	that the temperature is going up and in the last century it 
	went up about one degree Fahrenheit, I believe is what most 
	people have agreed to, and there has also been a lot of 
	testimony that for a period of time between 1500 to 1800, 
	whatever, that there was a period in which there was a
	cooling off.  So I just want to zero in on this.  You have 
	said and others have said and I think there is universal 
	agreement that we are going through a warming trend, and it 
	has been said by some people that that might not be 
	surprising coming from a cooling off period that you would 
	normally get warmer going through a warming trend.  So the 
	question that I would ask, as you look into the future, how 
	much warmer can it become before it is something that we 
	should really be alarmed about from your viewpoint, from 
	experiences?
	Dr. North.  Well, I will say this--well, two things.  One 
	is about the Little Ice Age and is it simply a recovery.  
	In other words, is the Earth's temperature a kind of 
	oscillating thing and that the slope upward now is just 
	recovery from a Little Ice Age which was apparently maybe 
	some natural phenomenon.  Well, I am not sure that that is 
	actually the right picture.  We don't know exactly the true 
	origins of the Little Ice Age but some studies, in fact, a 
	very good one by Tom Crowley, who will be speaking later,
	suggests that this is due to a series of volcanoes during 
	that period which caused a cooling.  It was not a great 
	cooling but some cooling.  So now it is--you know, now 
	that we are going through a period when they are not as 
	frequent as they were at that time, the Earth is simply 
	warming back toward equilibrium from that.  But now we 
	are also forcing the warming with the CO2 and other 
	greenhouse gases that are being emitted into the 
	atmosphere.  So while if we look at the future, what we 
	might think is that by the end of this century the 
	warming, if it continues and we do nothing about it, will 
	probably be somewhere between about three degrees 
	Fahrenheit and about eight degrees Fahrenheit.  Well, 
	three may not be so bad.  Eight would be pretty bad, 
	pretty bad.  And so in fact, even three is not as benign 
	as you might think.  You know, you can look at--for us in 
	our everyday life, three degrees Fahrenheit doesn't seem 
	to mean anything.  People after all live in Minneapolis 
	and they live in Houston.  But it really does affect 
	conditions.  Tree lines move.  There is a tree line that 
	runs right up the center of the United States along I-35 
	between Austin and Minneapolis.
	MR. WHITFIELD.  Right.
	DR. NORTH.  That tree line can move hundreds of miles 
	depending on just a couple of degrees or changes in 
	moisture.  So what looks like to us in our everyday life 
	not very much, if these things persist for a long time, 
	there are broader ecological responses at these kind of 
	low frequencies that are important.  So, I don't know all 
	of the bad or good things that might happen.  I mean, 
	there would probably be some winners and losers in a 
	situation like this.  And I have to confess to you, I don't 
	know enough about it.
	MR. WHITFIELD.  But you know as we grapple with this, we 
	have like a 250-year reserve of coal in America.  We all 
	want to be less dependent on foreign oil.  There are some 
	people that don't want to use fossil fuel at all, it would 
	be better to come up with new innovation, new technology 
	and move on to something cleaner and that can be a goal of 
	ours.  In representing a coal area of the country, I have
	a lot of constituents who come up to me and they will say 
	well, sure, there is some carbon dioxide caused by human 
	beings but there is more carbon dioxide emissions caused 
	by natural processes.  Now, I would just like to get your
	views on that comment.  Is there any basis for that or is 
	that just somebody--
	DR. NORTH.  There is a lot of carbon dioxide emitted into 
	the atmosphere every year and a lot of absorbed back into 
	the system every year, in fact, many times what humans put 
	in.  The problem is this.  There was an equilibrium 
	established between what is going out and what is drawn 
	back down every year by the system.  The oceans and the 
	biosphere, there is this exchange that goes on all the 
	time.  The problem with this is that the time scale, the 
	time constant, as we say, is quite long.  It takes a 
	couple of hundred years for these adjustments to 
	re-establish themselves, so if you dump in the carbon 
	dioxide much more rapidly than the system can accommodate, 
	it builds up in the atmosphere.  If we were to wait several 
	hundred years, then things may come back down, but we 
	don't have that luxury.  So the fact is, we are pouring it 
	in there faster than the system can dispose of it.  That 
	is the way--
	MR. WHITFIELD.  Thank you very much.  Who is next over 
	here?  Mr. Inslee.
	MR. INSLEE.  Thank you.  Just on that note, Dr. North, I 
	have heard the CO2 that we put in today in the atmosphere 
	could be there as long as 100 years?
	DR. NORTH.  A couple of hundred years.
	MR. INSLEE.  I want to use Dr. Wegman's expertise to try to 
	understand an interesting phenomenon.  You talked about 
	social networking.  I thought you could give us some insights 
	about that.  Dr. Naomi Oresky of the University of California 
	at San Diego published a study in Science magazine some time 
	ago.  She and her team selected a large random sampling of 
	928 articles about global warming that have been published 
	in peer-reviewed scientific journals and she wanted to look 
	at what they said, these 928 randomly selected peer-reviewed 
	articles about whether they accept or reject or question the 
	idea that humans are contributing to global warming.  Of 928 
	studies, what do you think percentage questioned the 
	proposition or rejected or even cast doubt on the proposition 
	that humans were causing global warming?  What do you think, 
	Dr. Wegman?  What percentage?  Zero.  Zero percentage of the 
	scientifically peer-reviewed articles drew the same conclusion 
	that my good friend Joe Barton drew, that there is doubt about 
	this.  Zero.  Now, my question is, another study looked at 636 
	randomly selected articles about global warming chosen from 
	the New York Times, the Washington Post, the L.A. Times, and 
	the Wall Street Journal.  Of those randomly selected 
	publications and those well-respected publications, what 
	percent cast doubt as to the cause of global warming?  What 
	do you think?
	DR. WEGMAN.  Probably about 50 percent.
	MR. INSLEE.  Fifty-three percent.  You win the prize for the 
	day of closest guess, or as you say, estimation.  Over half 
	of the popular articles suggested there is a significant 
	question as to whether or not humans are contributing to 
	global warming but zero percentage of the peer-reviewed 
	science.  Now, I believe that is one of the reasons that 
	Congress has not acted on this because frankly, the press is 
	creating doubt where there isn't any.  So the question of a 
	social scientist, the social networks, do we have a problem 
	with the press that are hanging out in the bars all together 
	too much too like the climatologists or what is your 
	explanation for this huge anomaly?
	DR. WEGMAN.  Well, there is no doubt in my mind that there 
	are two camps in the publication literature as well in the 
	popular press and, they are competing just like I suggested 
	that academics compete in social science that there is two 
	networks that are trying to promote different agendas.
	MR. INSLEE.  Well, my point is, I hope the press starts to 
	get off the story of doubt and get on the story of a 
	scientific consensus which exists in those 900 articles, and 
	no one should report this hearing unless they say that 
	because both you and Dr. North and every single person who 
	is going to testify today is going to say that there is a 
	scientific consensus that humans are responsible for at least 
	a portion of the global warming that is taking place.  Now, I 
	want to ask Dr. North if we can put this slide up here about 
	the CO2 and go back to the one he had there just a moment 
	ago.  Dr. North, I gave some of a very inarticulate 
	description of how carbon dioxide works to trap energy in the 
	planetary system.  Could you give a little better 
	explanation?  We will see that all the scientists, everybody 
	has projected levels of approximating double of pre-industrial 
	times if we don't change our course.  Could you explain in a 
	little better way how carbon dioxide affects the energy 
	balance of the Earth?
	DR. NORTH.  I will try.  First of all, carbon dioxide is well 
	mixed in the atmosphere so it isn't just lying down on the 
	surface.  It is very well mixed.  This process takes a few 
	months but--and in fact, if you emit it in one hemisphere of 
	the Earth, it takes about a year or two before it homogenizes 
	throughout the world.  So whether you emit your gas, your CO2 
	in Texas or anywhere else, it doesn't make any difference. 
	It winds up homogeneous throughout the world.  So what 
	happens now?  So the sunlight comes in, passes right through 
	the CO2 and warms the ground.  The ground in contact with 
	the atmosphere through latent heat release, that is, 
	evaporation from the surface and just sensible heat convection 
	to the surface warms the atmosphere.  So and then we establish 
	an equilibrium because the radiation going out to space 
	matches exactly what comes in over a long-term average.  So 
	that is the energy balance of the Earth.  Now, suppose you 
	turn up the carbon dioxide a little bit in the atmosphere.  
	Well, one thing that happens is, since the gas homogenizes 
	all through the planet, all around the planet.  The level up 
	in the atmosphere where the CO2 emits to space goes up a 
	little bit and higher in the atmosphere, 50 meters or 
	something like that if you double it.  That means it emits 
	from a cooler place in the atmosphere once you have doubled 
	it.  That means the amount going out isn't as much as it was
	before.  So what happens is, you have to warm the surface in
	order to regain the equilibrium.  That is a complicated
	explanation.  But in the process right in the middle of this,
	you warm the planet a little bit, more water comes into the 
	atmosphere from the oceans and other wet surfaces.  Water 
	vapor is also a greenhouse gas so this process gets amplified 
	maybe a factor of two.  So basically, I mean, what you said
	about the blanket is more or less right.  A slightly more
	technical discussion is well, when you put in more of this 
	stuff, it now emits from a higher place from a cooler surface
	rather than a warm surface so the radiation out to space is 
	less, you have got to warm up the planet to match again.  
	Sorry for such a long-winded answer.
	MR. WHITFIELD.  Thank you.  The gentleman's time has expired. 
	Mr. Walden.
	MR. WALDEN.  Thank you very much, Mr. Chairman.  Dr. North,
	what are some of the biggest natural emitters of CO2?
	DR. NORTH.  Well, there are many.  Decaying biological matter 
	is one, so rotting, decaying at the floor of the great forests
	and all over the planet, respiring animals and so forth.  So 
	there are many--
	MR. WALDEN.  What about forest fires?
	DR. NORTH.  Forest fires contribute but not nearly as 
	significant as these other natural products, and also volcanoes
	of course emit CO2 but on our scale, I mean, that is sporadic. 
	It does happen from time to time and of course it is the 
	historical origin of CO2 in our atmosphere but--
	MR. WALDEN.  And what consumes--
	DR. NORTH.  --it is not important.
	MR. WALDEN.  What consumes CO2?
	DR. NORTH.  So what consumes CO2 is the biological matter, the
	photosynthesis process, so sunlight is combined with--
	MR. WALDEN.  Plant matter--
	DR. NORTH.  --chlorophyll in the plant leaves and that is 
	converted to--so it removes CO2.
	MR. WALDEN.  So younger, healthier plants and trees consume 
	more CO2 than older, dying--
	DR. NORTH.  As they grow, they consume.  Right.  You are 
	making wood with the carbon.
	MR. WALDEN.  Because I also in my other part in the Congress 
	chair the Subcommittee on Forests and Forest Health and we 
	see--
	DR. NORTH.  That is very important.
	MR. WALDEN.  --these overgrown, decaying and dying forests.  
	We see fires occur that emit far more than CO2.  They emit a 
	lot of other noxious gases.  They have--
	DR. NORTH.  Sure.
	MR. WALDEN.  You know, the smoke will settle on the valleys.  
	I mean, it causes all kinds of problems and then the decaying 
	matter sits there for 3 or 4 years rather than being processed 
	and a new forest planted sooner.  Are you aware of any research
	that would indicate that by planting sooner, getting a healthy 
	forest a start faster, you might begin consuming carbon quicker
	than just leaving it to regenerate naturally?
	DR. NORTH.  Well, you are getting way off from my field but,
	intuitively, yes.
	MR. WALDEN.  All right.  Dr. Wegman, in your report, it is
	page 27, you say a common phrase among statisticians is 
	correlation does not imply causation, and you go on to say the 
	variables affecting Earth's climate and atmosphere are most 
	likely to be numerous and confounding, making conclusive 
	statements without specific findings with regard to atmospheric 
	forcings suggests a lack of scientific rigor and possibly an 
	agenda.  What do you mean by that?
	DR. WEGMAN.  Well, as we--when we were talking about tree ring 
	growth, for example--
	MR. WALDEN.  Right.
	DR. WEGMAN.  --there are many, many factors.  Moisture as 
	well as--
	MR. WALDEN.  Carbohydrates.  Right.
	DR. WEGMAN.  And nitrates, for example, that are emitted into 
	the atmosphere.  All of those affect tree ring growth.
	MR. WALDEN.  Can you pinpoint temperature in a tree ring?
	DR. WEGMAN.  Well, presumably there is some element of that.  
	I am not an expert on tree ring dendrology but presumably all 
	other factors being equal, if things are warmer, there is 
	more sunlight, there is a longer growing season, presumably 
	the trees are going to have wider tree rings.  So the issue 
	though is the confounding factors.  If you simply say that 
	this tree ring growth, what is called the late wood density, 
	is higher, that means the temperature is higher and ignore 
	all the confounding factors, you are certainly not teasing 
	out what really is the temperature.
	MR. WALDEN.  Now, we have seen the slide a couple of times 
	from my colleague from Washington, Mr. Inslee, that shows 
	CO2 levels back 160,000 years.  Can either of you tell me, 
	how do we know with precision what happened 160,000 years 
	ago?
	DR. NORTH.  Would you like me to--
	MR. WALDEN.  Sure.  Maybe from you, Dr. Wegman, 
	statistically, what does that mean and how do you evaluate 
	it, and Dr. North, from you maybe, the science behind--
	DR. WEGMAN.  Well, we have read actually Bradley's work on 
	this material so essentially when snow gets deposited, it 
	gets compressed, ultimately it becomes a second layer 
	called a firn, f-i-r-n, and then ultimately ice and when 
	the snow gets compressed it has ice, so it has bubbles of 
	air in there and presumably what is happening is that as 
	they drill ice cores down and go further into the past, 
	presumably 160,000 years of ice, they can look at these 
	microscopic bubbles of air and get the greenhouse gas 
	composition associated with that.  So that is again a 
	statistical estimation process--
	MR. WALDEN.  Are you comfortable with that process as a 
	statistician, not as a--
	DR. WEGMAN.  Well, presumably that curve that we have 
	seen a couple of times from Congressman Inslee should 
	have error bars as well associated with it.
	MR. WALDEN.  Should have what?
	DR. WEGMAN.  Error bars associated with it, imprecision,
	how much variability there is.
	MR. WALDEN.  And do we know what that would be?  I guess 
	he has left.  So we are--it is much like the criticism 
	Dr. North had of the Wall Street Journal report where 
	it lacked the 95 percent--
	DR. NORTH.  Yes, we would like to see those error bars. 
	That is very--
	MR. WALDEN.  Yes, we would like to see it as politicians 
	in our polls too to know, what plus or minus are we 
	dealing with here.  Thank you, Mr. Chairman.  Thank you,
	gentlemen.
	MR. WHITFIELD.  Ms. Schakowsky.
	DR. NORTH.  I would like to point out that we now 
	actually can go back 650,000 years.  Six hundred and 
	fifty thousand years in Antarctica in the past year.
	MR. WALDEN.  With precision?
	DR. NORTH.  Just not 150 but 650,000 years, still no 
	CO2 at this level.
	MR. WALDEN.  There is still no what?
	DR. NORTH.  No CO2 at this same concentration.
	MR. WALDEN.  I see.  Thank you.
	MS. SCHAKOWSKY.  I wanted to explore a little bit the 
	statement that Chairman Barton made.  He was referring to, 
	I think it was 1975 or sometime in the 1970s when 
	apparently there was a prediction of cooling, that actually 
	the planet was getting cooler, and here is my question, 
	and maybe I am not asking the right one and you could fill 
	me in on that.  But could not--and he used it, I thought, 
	as making the point that science is not conclusive.  But I 
	am wondering if one could not also see it as a confirmation 
	that human activity is in fact causing fairly dramatic 
	change in the climate, something that may not have been 
	factored in in 1975 but the science based on sort of older 
	predictors.  So I just wanted to ask how to interpret--and 
	first of all, is that the case that it was predicted to be 
	a cooling period?  Let me ask Dr. North, the climate 
	scientist, first.
	DR. NORTH.  Yes, there was a prediction made in the 1970s by 
	Reed Bryson, a professor at Madison.  He probably gave us all 
	a hard time about this because I have heard this a thousand
	times in the last year or so, few years.  So but, there are 
	two competing factors.  There is the dust in the atmosphere, 
	the tiny aerosols, tiny droplets of water and they come from 
	air pollution and volcanoes and other things but mainly air 
	pollution in our urban areas, manufacturing processes and so 
	on.  So out come these tiny droplets.  Well, they scatter 
	the sunlight back to space and therefore tend to cool the 
	planet a little bit.  The other competing factor is the 
	greenhouse gases.  They have been rising, and especially 
	during the war when there was a lot of energy produced and 
	not very much regulation on what was allowed to go into the 
	atmosphere.  At that time there was actually--the aerosols 
	were kind of winning the war, winning the war of balancing 
	the heat in the atmosphere, so there was a cooling that did 
	occur and probably Reed Bryson was right and that that was 
	probably the dominant effect.  But it didn't take very long 
	the way we are putting the greenhouse gases in exponentially. 
	The greenhouse gas is increasing roughly a percent per year 
	all together, so this is an enormous rise in the other 
	competing factor which causes the warming.  So the thinking 
	is that the warming has now become much greater than the 
	cooling due to the aerosols.
	MS. SCHAKOWSKY.  And haven't we--because of the hole in the 
	ozone layer, haven't we reduced aerosols or--
	DR. NORTH.  Well, the ozone layer, I would give--that is a 
	completely different story, so I would rather we not get off 
	to that.
	MS. SCHAKOWSKY.  Okay.  There was another scientific question 
	I wanted to ask you and again I am not sure how to phrase 
	it.  There was something about variability, and isn't there 
	a conclusion that could be made that if there is a great 
	variability, that that might be something that we really need 
	to worry about in fact that the effects of carbon dioxide in 
	the atmosphere in fact may be worse than we thought if we 
	are--
	DR. NORTH.  Yes.  There are natural fluctuations in the 
	system just as weather tickles the whole system and the whole 
	thing rumbles.  I mean, we have a climate system that sort of 
	rattles around, so this is the part that we call natural 
	variability.  It is a kind of noise in the system.  But then
	when we apply these nudges that are continuous, then we get 
	a secular trend and the noise on top of it.  And by the way, 
	that does tend to be a linear process.  There have been many, 
	many studies with climate models, and while of course they 
	are not perfect, they do imitate the atmospheric climate 
	system quite well, and for small nudges like the ones we are 
	talking about, I mean, they seem to us to be quite big but 
	in fact, in that system, they are tiny.  We are changing the 
	temperature a degree or two Kelvin compared to 300, so they 
	are tiny.  So this is actually a fairly linear process.  The 
	signals that we see in the system from warming and cooling 
	and other things, pretty linear, not that nonlinear.  So 
	natural variability is there and we worry that we don't 
	understand every bit of it.  For example, it could be that
	there are slow processes in the climate system such as the
	deep oceans, the overturning and so on of the deep oceans,
	and it could be that that is the underlying reason for 
	whatever this medieval warm period was.  We are not sure 
	about that.  It could be that some warm water surfaced.  
	What we know now though is that that is not the cause of 
	the warming in the last 50 years.  The warming in the last 
	50 years could not have been because of--we now have data. 
	We know that is not the reason.  In fact, if we look at the 
	map of warming, we see that it is warming more over the 
	continents than it is over the oceans.  They are being 
	pulled along because they are not as heavy, they are not 
	as inertial.  So the fingerprints of the warming are 
	exactly what we would expect if carbon dioxide were the 
	reason.
	Now, as we go back 1,000 years, we don't have all that 
	information to put in there to check it out so we don't 
	know exactly why that might have happened then but we 
	have a very good idea of what has been going on the last 
	100 years.
	MS. SCHAKOWSKY.  Thank you.
	MR. WHITFIELD.  The gentlelady's time has expired, and 
	Ms. Baldwin, you are recognized.
	MS. BALDWIN.  Thank you, Mr. Chairman.  As has been 
	referenced earlier in several opening statements and some 
	questions, we know how the tobacco industry wanting to keep 
	doubt in the public mind and in fact in 1993 the Wall Street 
	Journal published a front-page expos� on how the tobacco 
	industry had kept the public doubt alive about whether 
	smoking caused cancer.  For four decades the big tobacco 
	companies funded a sham research organization to feed the 
	public doubt about the health effects of smoking, and 
	despite smoking being responsible for over 400,000 deaths 
	a year, that strategy worked tremendously well for decades. 
	The Wall Street Journal quoted one big tobacco employee who 
	said, and I quote, "The scientists can come from Mars but no
	matter how obscure or misbegotten, as long as they are 
	willing to tell the scientific lie that it is not proven, 
	the tobacco industry is off the hook."  In May of this year, 
	we learned that some of the same people who worked on tobacco 
	also worked to confuse the consensus on global warming.  
	Mark Hurtsgard reported in Vanity Fair that for 20 years 
	Dr. Frederick Siete directed $45 million in medical research 
	for R.J. Reynolds to maintain a hint of doubt about the
	hazards of smoking.  In the 1990s Sietes turned his attention
	to global warming.  Dr. Sietes assaulted the integrity of the 
	Intergovernmental Panel on Climate Change on the op-ed page 
	of the Wall Street Journal.  He accused the Clinton 
	Administration of misrepresenting the science and authored a 
	paper which said that global warming was an exaggerated 
	threat.
	These people have a plan.  They want this hearing to stand 
	for the proposition that there is not a consensus on global 
	warming and they have stalled action for a decade or two and 
	they think they can drag it out even longer.  So Dr. North, 
	I am wondering if you can help put this in context.  
	Dr. Mann had concluded that the late 20th Century warmth in 
	the Northern Hemisphere was unprecedented during the last 
	1,000 years.  You said very clearly in your testimony that 
	Dr. Mann's conclusion has been subsequently supported by an 
	array of evidence.  We have a high level of confidence that 
	late 20th Century is the warmest period the planet has seen 
	in the last 400 years and you found it was plausible that 
	the planet is warmer than it has been in 1,000 years.  Is 
	that a fair summary?
	DR. NORTH.  Yes.
	MS. BALDWIN.  You said it was plausible that the planet is 
	warmer now than it has been any time in the last 1,000 years.  
	Has anyone provided affirmative evidence that there has been 
	a warmer period in the last 1,000 years?
	DR. NORTH.  No, we have not.  That is what we mean by 
	plausible, that there just doesn't seem to be any counter 
	information, so it is a reasonable thing to--
	MS. BALDWIN.  Is it plausible that human beings have caused 
	greenhouse gas emissions that are contributing--I am sorry. 
	Let me put it in the negative.  Is it plausible that 
	human-caused greenhouse gas emissions are not contributing 
	to global warming?
	DR. NORTH.  It is not plausible.
	MS. BALDWIN.  How confident is the scientific community that 
	human emissions are contributing to global warming?  
	Seventy-five percent, 80 percent?
	DR. NORTH.  In the scientific--in the climate science 
	community, I think that Mr. Inslee's quote about the number 
	of papers and who says yes and who says no tells the story.
	MS. BALDWIN.  Okay.
	DR. NORTH.  It is hard to find anyone who works in this 
	field who is opposed.  I mean, if somebody can come up with 
	a really good physical explanation for why this is false, 
	they will win the Nobel Prize.  So there are a lot of people 
	who might be attracted to the idea but we can't find any.
	MS. BALDWIN.  Well, finally, I just want to ask you about 
	the IPCC report since we have been hearing a lot about it. 
	Does the NRC report in any way discredit the IPCC's 2001 
	third assessment report?
	DR. NORTH.  Well, we have some differences with the details 
	of the hockey stick curve and we said that.  We are a 
	little less confident.  I mean, our error bars as we have 
	been saying, our margin of error is a little larger than 
	what was stated in that report and that is natural.  As we 
	go on and learn more, we adjust and adapt.  So, no, we 
	don't believe individual years--Dr. Wegman said this, and 
	we agree.  We don't trust individual years, the 1998 or 
	2006 or something as being the warmest of any time period 
	because we can't state things to that degree.
	MS. BALDWIN.  Just to clarify, my question was, did your 
	report in any way discredit the IPCC's 2001 third assessment 
	report?  Would you view--
	DR. NORTH.  No, we wouldn't--
	MS. BALDWIN.  --what you are describing as discrediting 
	that report?
	DR. NORTH.  No, it doesn't discredit it.
	MS. BALDWIN.  Okay.  Thank you.
	MR. WHITFIELD.  Thank you, and after almost 5 hours, that 
	concludes the first panel, so we should be through with 
	the second panel in about 10 hours.  Dr. Wegman, I want to 
	thank you very much and Dr. North for your testimony and 
	obviously this is a subject matter of great interest and 
	importance and we thank you for your testimony, and now I 
	look forward to the second panel and so I will release you 
	all.  And on the second panel we have another distinguished 
	group of individuals.  Mr. Thomas Karl is director of the 
	National Climatic Data Center from Asheville, North Carolina. 
	Dr. Thomas Crowley is the Nicholas Professor of Earth System 
	Science at Duke University.  Mr. Stephen McIntyre of Playter
	Boulevard in Toronto Canada, and then Dr. Hans von Storch, 
	who is the director of the Institute for Coastal Research 
	who flew to this meeting from Germany exclusively for this 
	meeting, and Dr. Storch, how do I pronounce the name of 
	your town in Germany where you are from?  On here it says 
	G-e-e-s-t-h-a-c-h-t.
	DR. VON STORCH.  Geesthacht.
	MR. WHITFIELD.  Geesthacht.  Okay.  Anyway, we welcome all 
	of you, and as you know, this is an Oversight and 
	Investigations hearing and it is our customary manner to 
	take this testimony under oath and I would ask you, do any
	of you have objection to testifying under oath?  And I am 
	assuming you do not need legal counsel.  So if you would 
	please raise your right hand.
	[Witnesses sworn.]
	MR. WHITFIELD.  Thank you very much.  You all are now under 
	oath, and Mr. Karl, we will start with you and we will 
	recognize you for your 5-minute opening statement.

STATEMENTS OF DR. THOMAS R. KARL, DIRECTOR, NATIONAL CLIMATIC DATA 
CENTER; DR. THOMAS J. CROWLEY, NICHOLAS PROFESSOR OF EARTH SYSTEM 
SCIENCE; DR. HANS VON STORCH, DIRECTOR OF INSTITUTE FOR COASTAL 
RESEARCH; AND MR. STEPHEN MCINTYRE, TORONTO, ONTARIO

	DR. KARL.  Mr. Chairman, members of the committee, I am 
	pleased to have the opportunity to testify before you 
	today.  I am the Director of NOAA's National Climatic Data 
	Center.  The National Climatic Data Center houses the World 
	Data Center for Paleoclimatology, which includes the data 
	sets that have been used to reconstruct temperatures for 
	the past 1,000 years or more.
	I was one of the two coordinating lead authors for chapter 
	2 of the Intergovernmental Panel on Climate Change, the 
	IPCC 2001 assessment.  The primary intent of the IPCC 
	periodic assessments is to provide government policymakers 
	with the latest and most comprehensive scientific 
	information possible about the human influences on our 
	global climate in a language that has meaning and relevance 
	to government policymakers.  Our responsibility as 
	coordinating lead author was to act as co-chair during the 
	lead author chapter meetings.  Each chapter has multiple 
	lead authors and chapter 2 had 10 lead authors.  Chapter 2 
	was to assess the data for changes and variations in 
	climate.  Coordinating lead authors are ultimately 
	responsible for ensuring that the final version of the 
	chapter is delivered to the IPCC bureau on schedule.  Each 
	chapter is agreed to by all lead authors and discussed and 
	reviewed with other chapter lead authors.  There is a very 
	lengthy review process which includes review editors to 
	oversee the review process.  In 2001 the IPCC report 
	concluded, and I quote, "New analyses indicate that the 
	magnitude of the warming over the 20th Century is likely to 
	have been the largest of any century in the last 1,000 
	years," and I emphasize warming here, the magnitude of the 
	warming.  Those are my words.  "The 1990s are likely to have 
	been the warmest decade of the millennium in the Northern 
	Hemisphere and 1998 is likely to have been the warmest year." 
	These findings were developed after careful consideration of 
	the published literature on this topic in 2001.
	The IPCC lead authors considered uncertainties related to 
	two types of temperature reconstruction errors.  Such errors
	can be thought of as having two fundamentally different 
	sources.  I will use some technical terms.  Parametric and 
	structural, but I will define these.  Parametric uncertainty, 
	which results from finite sample sizes to estimate 
	coefficients of a statistical model, is much less important 
	than structural uncertainty.  Human decisions that underlie 
	the development of the reconstructed time series may be 
	thought of as forming a structure depicting both real and 
	artificial behavior in paleoclimatic data.  Assumptions 
	that guide the decisions made by the experts may not be
	correct.  More important factors may have been ignored.  
	These possibilities lead to structural uncertainty.  
	Structural uncertainty can only be estimated by comparing 
	the differences of equally plausible reconstruction 
	methods.  The IPCC 2001 lead authors were able to estimate 
	structural uncertainty associated with the IPCC findings 
	because of the availability of several reconstructed time 
	series.
	It is important to note the language used by IPCC in the 
	2001 assessment included an expert assessment of the 
	certainty of various findings.  The IPCC reported findings 
	when the probability of being true reflected certainty 
	between 66 and 90 percent, or in odds terms, better than 
	two to one.  Lead authors were asked to develop findings 
	based on at least three levels of certainty, likely, 
	better than two to one odds of being correct, very likely, 
	better than nine to one odds, and virtually certain, 
	better than 99 to one.  These odds of probability were 
	based on the lead author's assessment of the published 
	literature and in consideration of thousands of expert 
	review comments.  I note that such expert assessments in 
	related fields such as the probability of precipitation 
	forecasting have proven to be quite reliable.
	Several research teams have challenged the reconstructed 
	temperatures featured in IPCC.  These challenges are not 
	without validity.  But now each of the challenges have 
	been assessed in a variety of new analyses.  For the 
	past several years there have been at least half a dozen 
	new analyses using many of the same paleoclimatic data
	featured in IPCC 2001 as well as new data covering longer 
	time periods or slightly expanded geographic coverage.  
	Of all these analyses, none show temperatures during the 
	past 1,000 years higher than the last few decades of the 
	20th Century and into the 21st Century.  These analyses 
	used different statistical methods, various types of 
	paleoclimatic data and different temperature calibration
	approaches.
	In June, the National Research Council reassessed the 
	1,000-year reconstructed time series.  The NRC not only 
	assessed the paleoclimatic data but considered how well 
	the data stands up to our ability to simulate the temperature 
	record of the past 1,000 years.  The NRC found that for the 
	most part, climate model simulations are consistent with 
	reconstructed paleoclimatic data of the Northern 
	Hemisphere.  The NRC report indicates it is plausible, as 
	we heard, that the last few decades of the 20th Century 
	were warmer than any other time during the past 1,000 
	years.   I note the NRC does not define the odds of 
	probability associated with the term "plausible."  In 
	contrast to IPCC 2001, the recent NRC report did not 
	highlight the rate of temperature increase during the 
	20th Century compared to the previous 10 centuries.  I 
	note the rate of temperature increase is also relevant 
	to our ability to adapt to changes in both our society 
	as well as the planet's ecosystems.
	In order to improve our estimates of reconstructed 
	temperature, more proxy records await our extraction.  
	Setting out to extract and calibrate proxy paleoclimatic 
	data is necessary but not sufficient to reduce further 
	uncertainty.  The data from proxies must also be accessible 
	by the broader science community for analysis.  At the 
	present time there is no formal process whereby federally 
	funded scientists must submit their data to a long-term 
	data archive facility for use by the general community.
	In conclusion, considering the additional evidence since 
	the IPCC 2001 assessment, I would extend the IPCC 2001 
	statement about the Northern Hemisphere temperatures in 
	the 1990s being higher than any other decade during the 
	past 1,000 years with probability of better than two to 
	one to include the most recent two decades.
	Thank you, Mr. Chairman and committee members, for 
	allowing me the opportunity to discuss and inform the
	committee.
	[The prepared statement of Dr. Thomas R. Karl follows:]


PREPARED STATEMENT OF DR. THOMAS R. KARL, DIRECTOR, NATIONAL 
CLIMATIC DATA CENTER, NATIONAL OCEANIC AND ATMOSPHERIC 
ADMINISTRATION, U.S. DEPARTMENT OF COMMERCE




	MR. WHITFIELD.  Thank you, Mr. Karl, and Dr. Crowley, you 
	are recognized for your 5-minute opening statement.
DR. CROWLEY.  Thank you very much for the opportunity to present 
my testimony.  I will briefly state my credentials and give a 
short history of the Mann et al. paper with respect to the 
Intergovernmental Panel for Climate Change report.
	As background, I received a Ph.D. in marine geology from 
	Brown University and I specialized in study of the 
	Earth's past climates.  Over the last few years I have 
	spent part of my time working on climate change over the 
	last 1,000 to 2,000 years.  You have gone over some 
	aspects of the Mann et al. paper ad nauseum so I am going 
	to skip over some elements of what I am going to say and
	then discuss aspects of how I perceived the Mann et al. 
	report was included in the IPCC, okay.  I was not part of 
	IPCC but I am familiar enough with some of the science 
	that was going on that I thought it might be useful.  But 
	it is my perception of it, okay.
	So with respect to the inclusion of the Mann et al. report, 
	especially into the summary for policymakers, at that time 
	there were three reconstructions that went back 1,000 
	years, okay, at the time of the IPCC 3, so back to the 
	Middle Ages.  Now, one of the reconstructions--Mann et al. 
	was the second to come along.  One of the reconstructions 
	uses completely different methodology from Mann et al., 
	and if I could have the second figure there, okay, and I 
	can't read that very well. Really focus on, if you can 
	even read, the right axis, okay.  That is temperature 
	variations.  Forget the left axis there, and that is time 
	over the last 1,000 years, and the Mann et al. 
	reconstruction is in green.  That is decadally smooth Mann 
	et al., reconstruction, okay.  And this other 
	reconstruction which I was involved in really stemmed from 
	a discussion I had at a meeting where people say well, I 
	don't believe Mann, and there was nothing written about 
	it.  They just say they don't believe Mann.  And so out 
	of this grew, I said okay, I got so exasperated.  We 
	just--I will go analyze some data myself and just see 
	what it looks like, and we deliberately took a very 
	different approach rather than using what they call the
	sealed method for reconstructing a temperature.  We took 
	this other methodology which has the scientific term 
	"bonehead" associated with it in which we just added up 
	all the individual curves and took the average, okay.  
	And the reason we do that in part is so we can see 
	exactly in the terms of the curve here, you can 
	understand exactly how your composite curve originates 
	from the nature of the raw data, okay, and that is real 
	easy.  If there is a bump, you can go back to the raw 
	data and see where it came from, okay.  And the other 
	reason for doing that is geological data is by
	definition dirty data and sometimes it is very helpful 
	sometimes to be somewhat conservative in the statistical 
	methodologies you employ.  So what we did is, the bonehead 
	approach using some of the data from Mann et al. but 
	other records also, some of which have been cited as 
	indicative of a medieval warm period, and even though some
	of these records locally clearly show temperatures locally 
	warmer than 20th Century during the Middle Ages, when we
	summed up all the different records, we got a pattern that 
	was surprisingly similar to what Mann had gotten as you 
	can see from the red curve there.  Yes, there are some 
	differences there but the similarities look a lot more--
	you know, a lot--there are more similarities than there 
	are differences there.  We stopped our analysis in 1960, 
	okay, so that is why we don't get this big tail at the 
	end.  But over most of it is pretty similar.  So this was 
	in some way was a very--it was a surprise.  I had no idea 
	what it would look like, but it suggested that the Mann 
	et al. result might be robust in terms of its pattern 
	about the relative magnitude of warmth in the Middle Ages 
	and what was happening there, when you go back to the raw 
	data which you can easily do with this type of 
	reconstruction, the reason we didn't get a very warm 
	medieval warm period was that whereas some places were 
	warm, others were cold at the same time so when you 
	averaged them, it came out to some value in between.  So
	we understood then why that happened, why we were getting 
	that result.
	Now, there is a follow-up to that.  Our reconstruction, 
	we weren't trying to say it was better than Mann or 
	anything.  We were just trying to do what is called a 
	sensitivity test on the Mann et al. result, okay.  Now, the 
	Mann et al. result was the only paper that actually 
	estimated the sensitivities, the uncertainties of your 
	conclusion which Dr. North has emphasized is very 
	important, and for that reason, I believe it was legitimate 
	to include that, to select that as the paper that would go 
	in to highlight the millennial perspective for IPCC 
	because it was the one that had the objectively determined
	uncertainties in the reconstruction, okay.  So that is 
	how it wound up in IPCC and they had some additional 
	information that it might be okay.
	Now, science progresses and sometimes past conclusions 
	have to be modified.  A notable example with respect to 
	IPCC involves this significance of satellite upper air 
	data that previously had not agreed with model 
	predictions.  Now they seem to, okay.  That is just the 
	way science goes.  Similarly, some papers have been 
	published since the IPCC suggesting greater variability 
	than Mann et al., and contrary to claims of the Wegman 
	report, and again, I should point out here, I apologize 
	for the sometimes poor use of terms that I have used to 
	describe Dr. Wegman and I apologize to Dr. Wegman for 
	that.  But contrary to the claims in that report, one of 
	these reconstructions used a completely independent data
	set for verification.
	Can we have the next figure, please?  And I was hoping 
	to have a pointer, but the main point here is what you 
	see here is--I just want to spend a little bit of time 
	on this because you are seeing basically the same net 
	conclusion as you see from Mann et al. even though we 
	had greater variability that Mann et al. in this 
	reconstruction, and again, this is sort of a slightly 
	sophisticated update of the bonehead methodology, okay.  
	So it is bonehead squared or something.  But what you 
	see here is we have reconstructions here in blue and red 
	and yellow, different length of time series, but it goes 
	back to about 500 A.D., and we have uncertainties 
	assigned to these reconstructions based on the uncertainty 
	in the overlap interval with the instrumental record here. 
	But the difference we get is that we have a completely 
	independent validation based on the methodology data from 
	borehole measurements of heat flow in the Earth's interior, 
	okay.  That is completely independent from the data we 
	use.  And statistically, we actually have two borehole 
	scientists on our team for that paper plus two sets of 
	statistical climatologists, I might add, that the 
	relationship between this low resolution borehole record 
	and this higher resolution surface reconstruction are 
	indistinguishable and yet the variations you see here are 
	much greater than what you see in Mann et al., okay, the
	variability.  We have a slightly warmer medieval warm 
	period than Mann et al. but even there if you take decadal 
	smoothing there, that peak value here in the medieval 
	warm period really at best approximates what happens in 
	the mid-20th Century, all right?  And again, because of
	the nature of the way we combine the data, we understand 
	exactly why it doesn't get really warm, okay.  And so 
	this is a paper that is coming out--well, it has actually
	been accepted by the Journal of Climate and will be out 
	sometime later this year.  So this is one of the things 
	we don't agree with Mann in terms of variability.  Others, 
	Mann has updated his reconstruction and he still believes 
	that it is the same.  So there are still differences in 
	the field but a number of other studies show higher 
	variability at that time.
	The interesting point about the higher variability and you
	have to be really aware of this is that it is not--some
	people may--it almost seems sometimes in reading papers 
	that people enjoy disproving Mann, okay, but one of the 
	things you have to be aware of, you have a reconstruction 
	that has higher variability and greater warming in the 
	Middle Ages.  What it means is, your climate system has
	higher sensitivity, okay, than the Mann et al. 
	reconstruction which has only small wiggles, okay, and 
	high climate sensitivity carries over to what the 
	implications are for carbon dioxide forcing because the 
	only--sensitivity means that if you have a certain amount
	of forcing, you either get a small response or a big 
	response, okay.  You have a system with low sensitivity,
	then it doesn't wiggle much.  If that was true for 
	carbon dioxide, you wouldn't have to worry about it.  
	You just close the door and throw away the key and keep 
	burning oil until you want.  If it has a high 
	sensitivity though, you have to start worrying, and the 
	implication of this result is that climate sensitivity 
	is much higher than before, okay. 
	So now, I may be almost out of time here, okay, because 
	I have spent a lot of time on this.  I have a few 
	comments--
	MR. WHITFIELD.  Dr. Crowley, you are about 4 minutes 
	over your time, but if you want to summarize, then there
	will be plenty of questions for you as well.
	DR. CROWLEY.  Okay.  I just wanted to highlight a couple
	points on the Wegman report.  I am not going to talk 
	about their assessment of the Mann et al. thing.  That is
	really--I disagree with them with respect to their 
	recommendations and I will just summarize these 
	disagreements, one being that the interactions with the
	statistics community have really increased very 
	significantly and I think that Dr. Wegman and his 
	colleagues may have been working with--had a small sample 
	problem just looking at some of the paleoclimate papers 
	because in fact it is a rather substantial improvement
	in the interactions between real statisticians and the 
	climate--and percolating down into the paleoclimate 
	community, and that is true even for the IPCC.  The key
	chapter in the new IPCC report actually has a 
	statistician and a statistical climatologist as co-lead 
	authors of this chapter, okay.  So they are being well 
	integrated into the process.
	And finally, with respect to authors should not assess 
	their own work, this sounds fine in theory but in 
	practice it seems almost unworkable because who else
	but experts can produce an expert report.  And with
	respect to the IPCC, I think it is a marvelous document.
	It involves hundreds of scientists, reviews of thousands 
	of papers, and received on the order of 10,000 comments
	for each of the earlier drafts.
	MR. WHITFIELD.  Are you about ready to conclude, 
	Dr. Crowley?
	DR. CROWLEY.  So my feeling is that it is a very, very 
	thoroughly reviewed and vetted manuscript and I think 
	it is just about the best thing we have.
	[The prepared statement of Dr. Thomas J. Crowley 
	follows:]

PREPARED STATEMENT OF DR. THOMAS J. CROWLEY, NICHOLAS 
PROFESSOR OF EARTH SCIENCE SYSTEM, DUKE UNIVERSITY

I thank the committee for the opportunity to submit my response
to the findings of the NRC and Wegman Reports.  As background 
to my testimony, I will briefly state my credentials.  I 
received a Ph.D. in marine geology from Brown University and
have a long interest in the history of the Earth's past 
climates, both from a modeling and observational viewpoint.  I 
have published about 100 peer-reviewed papers and have
co-authored a book on the subject.  I have worked in academia, 
the private sector, and at two government agencies - at NSF as 
a program director in climate and at NASA/Goddard Space Flight 
Center as a National Research Council senior fellow.  I am 
presently the Nicholas Professor of Earth Systems Science in 
the Nicholas School of the Environment at Duke University.  
Because this hearing has been called to better understand the 
influence of the much-discussed 1998 and 1999 papers by 
Michael Mann, Raymond Bradley, and Malcolm Hughes, I think it
would be useful to provide a brief scientific background to 
the subject.  Prior to 1998 there had been only one attempt 
to summarize the various types of data from past climate to 
get a broader picture as to how it has changed over the last
few centuries.  In 1998 Mann et al. introduced a new 
technique to develop more quantitative estimates of the 
nature of climate change since AD 1400 for the northern 
hemisphere, and in 1999 the group extended that record back 
to AD 1000 and concluded that the late 20th century warming 
was the largest in the last 1000 years.   This report was
among a number of scientific studies highlighted in the IPCC
Third Assessment Report (TAR) to conclude that "there is new
and stronger evidence that most of the observed warming over
the last fifty years is attributable to human activities". 
With respect to the committee's interests in whether the 
objectivity of the IPCC with respect to the Mann et al. 
studies I elaborate on several points below.  At the time of
IPCC TAR it represented the best estimate of past millennial 
temperatures and their uncertainties, and that the most 
important conclusion from IPCC (stated above) does not depend
on the Mann et al. papers for its credibility, and are even 
more robust today than they were in 2001.
The final part of my presentation involves a number of 
objections, both major and minor, to the Wegman Report. 
I have five main points to make concerning the following 
subjects:
(1) The relation between the Mann et al paper and the IPCC 
Third Report in 2001. The Mann et al paper was certainly 
influential in the IPCC Third Assessment Report (TAR), but 
so were many other papers.  But the papers that made the
biggest difference were the ones focusing on the instrumental
record in which it was shown that models and data could not
be reconciled unless an anthropogenic greenhouse influence
was invoked. The most compelling driver of all was the fact 
that global temperatures kept going up and up since the 
1996 report, and meltback of glaciers increased in many 
parts of the world.  I might add that this trend has only
accelerated since 2001, with melting in the Arctic and on 
Greenland reaching alarming levels.
(2) The Mann et al paper in and of itself. At the time of 
IPCC TAR there were two other reconstructions going back 
to the Middle Ages, with decadally smoothed data showing,
at best, past millennial temperatures comparable to the 
mid-20th century warm interval.  One reconstruction 
(Crowley and Lowery, attached) using a completely different 
methodology agreed with Mann et al. quite well (Fig. 2).  
However, Mann et al. was the only paper of the three that
estimated uncertainties, and it is no surprise that this
paper was the one chosen to highlight the millennial
perspective for IPCC.  The significant criticisms of the 
Mann et al. paper that have been published since 2001 are 
by definition after the fact with respect to IPCC TAR. 
(3) The present state of our knowledge on millennial 
changes Science always progresses and sometimes past 
conclusons have to be modified. A notable example with
respect to IPCC involves the significant reassessment of
satellite upper air data that previously had not agreed 
with model predictions of increasing air temperatures in 
that region; new assessments indicated that the models and 
data were now in approximate agreement.  Similarly, some 
papers have been published in the last five years suggesting 
greater variability than Mann et al.  Contrary to the 
claims of the Wegman Report, one of these reconstructions 
(Hegerl et al., attachment 2) uses a completely independent
data set from borehole measurements (fig. 3) of the 
effects of air temperature change on heat flow in the upper 
part of the Earth's crust.   
	Because Mann et al. have more recently obtained 
	results similar to their earlier work, but now using 
	a different methodology, it continues to be necessary 
	to understand the causes of differences among the
	different reconstructions before the estimates of 
	higher temperature variability can be accepted.  
	Even if the latter estimates ultimately prove to be 
	more accurate, there is no room for gloating (as 
	sometimes seems evident in discussion of the newer 
	results), for the higher variability inevitably 
	implies a higher climate sensitivity, which is a 
	cause of much more serious concern for either the 
	committee, or society at large.  By this I mean 
	that for any given level of climate forcing from 
	carbon dioxide, the expected temperature response 
	would be larger than it would if the Mann et al. 
	reconstruction was ultimately deemed to be the 
	"final word" on the magnitude of past climate 
	change (see Hegerl et al., third attachment).
(4) The claim of unusual level of warmth for the late 
20th century is still valid for all but one of the new 
reconstructions.  Contrary to the conclusions of the 
the Wegman report, there is reason to believe in the 
unique nature of late 20th century warmth (this is the
only major point in which I differ from the NRC report). 
Although the early millennium records are small in 
number, the composite reconstruction agrees in the 
overlap interval (A.D.  1500-1960) with reconstructions
using more extensive data sets.  Furthermore, 
examination of the raw data indicates that even in the
high latitude northern hemisphere they show regional 
variations in the timing of warmth that is much greater 
than in the late 20th century.  In other words, some 
regions are warm and some cold - a very different 
pattern from the late 20th century, where almost every 
region has warmed over the last 100 years.  It is 
therefore no surprise that, when these records are 
composited, the sum value is smaller than for the late 
20th century.
(5) The conclusions and recommendations of the Wegman 
Report have some serious flaws.   In addition to a 
number of technical errors, large and small, the 
following comments can be made in the bullets on page 
two of the committee's summary of findings (fact sheet):
(a) bullet one (concerning specifics of Mann et al.) -
responses discussed above
(b) bullet two - "many of the proxies are reused in 
most of the papers....it is not surprising that would 
obtain similar results..."  This almost sounds as if  
it is wrong for everyone to use the best existing data! 
The more important point, and one not stated, is that 
different methodologies are employed by each of the
investigators.  Furthermore, there is nothing wrong 
with talking to or even collaborating with someone else 
in a field that you respect, and has expertise that you 
don't have.  The Wegman Report almost seems to imply 
that collaboration is equivalent to collusion, a result
that would apply to the Wegman Report itself if that 
were always true. 
The inference in the same bullet concerning the failure
of the peer review statement is an oversimplification.
The anonymity of peer review still allows papers to be 
rejected, as almost any scientist can testify.     As a 
former NSF program director, I have had significant 
opportunity to evaluate the peer-review system.  It is 
not perfect but in general the best work gets funded.  For
publications, editors usually select a variety of reviewers
who cover the different expertises in the study.  But it is 
just not practical to expand the number of peer reviews for
many publications - the work load is just too onerous for
the reviewing pool, and most people will simply decline the
request to review the papers.  Finally, I would like to 
comment that the Wegman Report now before the committee has 
not undergone any extensive peer review from anyone in the 
climate community prior to its submission to the committee
for inclusion into the record and, most problematically, 
possible use as a guide to further recommendations by the 
committee.
(c) Bullet three - the researchers do not seem to be interacting
with the statistical community.  This statement is based on a 
small subsample of paleoclimate papers.  Overall, there is
increasingly strong incorporation of statistical methodologies 
in the climate sciences, including increased interactions with 
statisticians.  For example, the National Center for 
Atmospheric Research has had a postdoctoral program for 
statisticians for thirteen years.  A key project jointly funded
by DOE and NOAA for detection and attribution of climate change 
involves not only several statistical climatologists but also 
explicitly seeks out input from statisticians.  The present 
(and key) IPCC Fourth assessment chapter on detection and 
attribution of climate change has a statistician and statistical
climatologist (with a training in applied mathematics) as 
co-lead authors.  Statisticians are welcome to respond to any of 
the chapters in the review process.  From these statements it is 
clear that the Wegman Report is somewhat uninformed with respect 
to the effort to include statisticians in the IPCC review process.
I might add that interactions between geoscientists and 
statisticians have long been hampered by what can only be described
by some as a condescending attitude from some statisticians that 
geoscientists were not employing the most recent, state of the art 
statistical methods.  Such attitudes almost guarantee subsequent 
poor communication and fail to recognize the unusual nature of 
"field laboratory" geoscience data, which are very different than 
"closed laboratories" where the conditions of an experiment are 
well controlled. The latter types of data require an intimate 
understanding of the raw data and simpler, more robust statistical 
methodologies that recognize the limitations of such data.
(d) Bullet four - authors of policy assessment should not assess 
their own work.  This statement may sound fine but in practice but
seems almost totally workable.  Who else but experts should 
produce an expert report?  The third and fourth IPCC reports 
involved hundreds of scientists around the world, a review of 
thousands of papers, and received on the order of 10,000 comments 
in the early stages of drafts.  The final summary for policymakers 
requires a vote - by government representatives of the signatory 
nations -- on every single sentence before it is accepted!   I can 
attest from personal experience that the resultant high quality of
the IPCC documents make them ideal choices for teaching graduate 
and professional courses because they are by definition our best
statement on the present state of knowledge of the climate system.
It is inconceivable to me that a report of this quality could be 
produced by a group of nonspecialists.
(e) Bullet five - paleoclimate data does not provide insight into
physical processes   The statement on physical processes is
completely wrong.  In fact, paleoclimate modeling results indicate
that about half of the decadally scaled variance between 1270 and 
1850 can be explained by natural variations in solar and 
(primarily) volcanic forcing.  When these forcings are carried
over into the 20th century, they cannot explain the 20th 
temperature rise.  Only greenhouse gases can explain the rise,
not only for the late 20th century, but also in part for the 
mid-20th century.  
In this same bullet the Wegman Report recommends that federal 
research should emphasize fundamental understanding of the 
mechanisms of climate change and should focus on interdisciplinary 
teams to avoid narrowly focused discipline research.  I find this
to be an extremely na�ve statement.  Climate studies are among the 
most interdisciplinary field that one can imagine - as just one 
example I submit a copy of a paper (attachment four) on causes of 
climate change over the last millennium that discusses changes in 
solar output, volcanism, trace gas variations in climate, tree 
rings, ice cores, climate models, impact of vegetation, etc etc.
There are many other examples of interdisciplinary activities.  
As a former program director at the National Science Foundation,
I think I can also speak for many present program managers in 
federal agencies concerning the lack of interdisciplinary 
activities on different projects.  This interdisciplinary is 
the core concept of terms such as "Global Change" and "Earth 
Systems Science" and as such the agencies have made a great 
effort at supporting interdisciplinary research.  Furthermore,
every major modeling group in IPCC addresses a host of 
interdisciplinary science.  
But it would be a big mistake to forget the lone investigator. 
Sometimes the most fundamental findings in a field come from 
these lone investigators (who may nevertheless have much 
contact with many others).  There must be room for individual
creative science in climate science.  

Summary and Concluding Remarks    In my view the debate over
the Mann et al paper is a tempest in a teapot.  It is 
legitimate material for scientific discussion but the 
implications with respect to the operations of the IPCC are 
unproven and seemingly based, in my opinion, much more on 
repetition of innuendo than on any real facts.  Although 
there is always a need for enhanced interaction with the 
statistics community, the lack of communication is seriously 
misrepresented in the Wegman Reprot.  I believe that this 
report should not be used as either a legitimate assessment 
of the science or as a guide to policy modification. 
Finally, I believe it is time to stop using Michael Mann as 
a whipping post and to start directing attention to the more 
important matters of whether anything should be done about 
global warming, and if so, what? 

Attachments:

1. Crowley, T.J., and Lowery, T.S., 2000.  How warm was the 
Medieval Warm Period?  Ambio  (publication of the Royal 
Swedish Academy of Sciences), v. 29, no. 1, pp 51-54.
2. Hegerl, G.C., Crowley, T.J., Allen, M., Hyde, W.T., 
Pollack, H.N., Smerdon, J., and Zorita, E., 2006.  Detection 
of human influence on a new, validated, 1500 year temperature 
reconstruction, Journal of Climate (accepted).
3. Hegerl, G.C., Crowley, T.J., Hyde, W.T., and Frame, D.J., 
2006.  Climate sensitivity constrained by temperature 
reconstructions of the past seven centuries.  Nature, v. 
440, 1029-1032. 
4. Crowley, T.J., Causes of climate change over the last 
1000 years.  Science, v. 289, 270-277.

	MR. WHITFIELD.  Thank you.  Dr. von Storch, you are 
	recognized for 5 minutes.
DR. VON STORCH.  Thank you very much for inviting me here.  
I just wanted to mention that I am joined here by my 
colleague, Eduardo Zorito, from the same laboratory sitting 
there in the back.
	Next transparency, please.  So I am just summarizing 
	my paper here.  So first scientific aspects.  So the 
	progression-type methods of the so-called hockey 
	stick studies of Mann, Bradley, and Hughes suffer from 
	a number of problems which should have been addressed 
	before the hockey stick was elevated to an 
	authoritative description of the temperature history 
	of the past 1,000 years.  It says 1,000 to 2,000 years 
	but that is an error.
	Second, the claim by the IPCC third assessment report, 
	that is the 2001, that there is reliable evidence that
	climate is beginning to change due to human action was
	based on a number of different lines of argument which 
	are insensitive to the validity of the MBH studies, that 
	is, the present debate about the validity of the hockey 
	stick is of marginal relevance for the detection of 
	present anthropogenic climate change.  I claim the 
	major problems are not of a statistical nature but are 
	related to the social practice of climate change studies.
	Next transparency, please.  In the Wegman report, let me 
	say a few words about the Wegman report.  We have in our 
	working group examined how serious the error of biased 
	centering would be on the overall results given a 
	temperature history reminiscent of the IPCC 1990 version. 
	The paper has been published and the effect is very minor. 
	It does not mean that it is not a glitch but it really 
	doesn't matter here, at least to the extent we could test 
	it.
	There are other aspects which are much more relevant I 
	would have hoped that Dr. Wegman would have taken this up, 
	that is, the usage of the trend as a key element for 
	training the progression model.  It is a bit funny to use 
	the trend to train something and I will show you in a 
	second what that means.
	And second, the method of something, what is called scaling,
	that is, that you artificially make sure that the variance 
	of the predictor, that is, the temperature, equals the 
	variance of the predicted temperature, the derived 
	temperature.  So you multiply it by a number so that it 
	just comes out as if you could explain the total variance
	by the proxy.  You cannot.  You know that you cannot do it
	and therefore you introduce an error which you cannot avoid.
	Third, we welcome the suggestion by Wegman and his 
	colleagues to invest much more effort to examine the error 
	structure in deriving temperature data from proxies.
	There are two main issues.  First is the homogeneity of 
	proxies.  If in the year 1960 the tree ring means something 
	for temperature--no, I mean--yes, it does not mean that this 
	is the same information in the year 1200.  It could be that 
	the process to get out the information from a 1200 tree ring 
	is different from the 1960.  Second, the instationarities of 
	the late proxy and temperature.  We know that there are some 
	problems at least that has been explained at the Academy 
	hearing that nowadays the link between temperature and CO2 
	seems to be damaged.  When Hughes was asked what the reason 
	could be, he gave three different hypotheses, and when he was
	asked, do you think it could have happened in the past, the 
	answer was yes.  So it could be that the link which we see 
	now these days in the past 100 years or so would be different 
	than previous times.  We cannot know that and we have to think 
	about how to model this effect.
	The next transparency, please.  That shows the danger of 
	relying on trends.  So you see here, a times series throughout
	the instrumental period, that is, the period when we think we
	have enough data to derive Northern Hemisphere mean annual 
	temperature from instrumental data, and you see in yellow, that 
	is the area when the method has been trained and then we see
	it has been trained from 1910--well, it has been trained for
	a longer time showing a 21-year running means.  And the red 
	curve is what the MBH method was indicating the temperature 
	variation should have been in this period and the black is a 
	new analysis of the climate research unit.  It was produced 
	after that was done, and now what you see here is that the 
	green and the black curve are very nicely coincident during 
	the trend but nothing else.  Nothing else is reproduced and 
	so it is just what this method is fixing up is the trend and 
	nothing else, or it may be so.  One should check that out.  
	And so this is a bit dubious.
	Next transparency, please.  Understand that you are concerned 
	about the quality control process of climate change science, 
	and I would claim that parts of climate change science, in 
	particular paleoclimatic reconstructions have suffered from 
	gatekeeping and insistence usage of reviewers.  I myself can 
	say that they were always the same type of reviews we got, 
	the same style and I am sure that it was the same person and 
	I am sure it was the person we have spoken about here quite 
	a bit.
	And I also claim that editors in science magazines have 
	failed to ensure the reproducibility of key results.  The 
	methods have not been described properly and their data one 
	could not access.  Part of the mess here is due to the 
	practice of Nature and Science that they have a bias towards 
	interesting results.  I mean, they have--their way of 
	operating is not only that the results are innovative and 
	valid but they must also be interesting.  Then what I think 
	is really not good that in the IPCC process experts assess 
	their own work.
	That is, to conclude this, climate change science has 
	suffered from limiting action of gatekeepers and the public
	preference for interesting results.  Climate change science 
	should provide stakeholders with a broad range of options 
	and not narrow this range to reduce numbers of options 
	preferred for certain world use.
	I was a bit disappointed about the comment from the lady 
	from Illinois who said aren't you afraid if you say this 
	that this would have negative implications for the policy 
	process.  I mean, is that really--I mean, I was kind of 
	shocked.  I mean, should we really adopt what we say if 
	that is useful for the policy process?  Is that what you 
	expect from science?  If we give advice, that we first think 
	is it useful for something.  I think that is not the way we 
	should operate, or if we do that, you should not listen to 
	us.
	Next transparency.  This is not to please the people on the
	right-hand side.  The acceptance of the IPCC in the community, 
	this is actually--it is very well accepted and it is very hard 
	to see this but it is the result of a survey which was asking 
	to what extent do you agree or disagree that the IPCC report 
	is of great use of the advancement of science.  That is on 
	the left-hand side.  And then you see a statistical 
	description of the responses.  At the bottom they would say
	strongly agree.  At the top they would say strongly 
	disagree.  And then there are--on the left-hand side there 
	are results from 1996 and on the right-hand side 2003, one
	block for U.S., the other for E.U., and you see in 1996 
	there was a median of three.  That means people, most said 
	well, it is useful.  In 2003 the median was two, so they 
	are much more convinced that this is done well.  And the 
	same result is with a question to what extent do you agree
	or disagree that the IPCC reports accurately reflect the
	consensus of thought within the scientific community.  So 
	there is broader agreement that the community is doing 
	right even though I don't think that the Oreskes study was
	done well and there have been numerous responses on that 
	which have not been accepted by science for whatever 
	reasons.
	The last transparency, please.  We have to keep in mind 
	that climate change science takes place in a cultural 
	context.  It has something to do with what we think we have 
	been trained at and a possibly remarkable result is that 
	the concept of anthropogenic climate change is not new in
	Western culture.  This is not a new invention in the 
	history of this.  We have documented very many cases and 
	the first scientific publication we have on that is from 
	1781 by a physician named Williamson from Philadelphia 
	who was speaking about the changing climate due to human 
	action.  At that time the weather in this part of the 
	world was greatly improved because of taking away forests.
	Second, climate change science is something what we call 
	post-mormal, that means it goes along with high 
	uncertainties and high relevance.  In that case, it is 
	quite normal that the boundaries between value-driven 
	agendas and curiosity-driven science get blurred and we 
	should admit that there is a considerable influence of
	extrascientific agendas on the scientific process of 
	climate change studies.  I think we have seen that today
	also.  The processes of climate change studies need to be
	analyzed and accompanied by social and policy scientists. 
	So this process we are seeing here, how we argue, we 
	should be something like--yes, always an analysis by 
	social scientists and I think what Dr. Wegman and his 
	colleagues started to do was quite useful in this respect,
	that we understand to what extent we are driven by 
	non-scientific motives, and this ends my presentation 
	here.
	[The prepared statement of Dr. Hans von Storch follows:]

PREPARED STATEMENT OF DR. HANS VON STORCH, DIRECTOR OF INSTITUTE
FOR COAST RESEARCH, GKSS-RESEARCH CENTER, GERMANY

Introduction of person
I, Hans von Storch, have been actively involved in climate 
science since the early 1980s. I have held positions with the 
Meteorological Institute of the University of Hamburg and at 
the Max-Planck Institute for Meteorology in Hamburg. At the 
present time, I am a director of the Institute for Coastal 
Research of the GKSS Research Center in Germany. I have 
co-authored more than 120 peer-reviewed articles on various 
issues of climate dynamics, climate statistics, climate change
and climate impact as well as the  textbook "Statistical 
Analysis in Climate Research" (together with Francis Zwiers) 
published by Cambridge University Press. I was a lead author 
of Chapter 10 of the Third Assessment Report of the IPCC, but
I am not involved in the Fourth Assessment Report of the 
IPCC.
Based on the scientific evidence, I am convinced that we are 
facing anthropogenic climate change brought about by the 
emission of greenhouse gases into the atmosphere.
For further personal details please refer to my web-page: 
http://w3g.gkss.de/staff/storch.
Hans von Storch
Director of Institute for Coastal Research, GKSS Research 
Center, Geesthacht, Germany
Professor at Meteorological Institute, University of Hamburg,
Hamburg, Germany
e-mail: [email protected], mobile +49 171 212 2046

Outline
I briefly address three aspects of the hockey-stick issue, 
namely 
1. Scientific aspects:
- How valid are the regression-type methodologies for 
reconstruction historical climates? 
- How relevant are these reconstructions for claims that we 
presently experience a climate change outside the range of 
what we consider as "normal" (no human interference).
2. The process of achieving success of a scientific knowledg
e claims in the climate science community:
- Independence of the review process or presence of 
gatekeepers.
- Reproducibility
- Selection process by Nature & Science.
- Acceptance by IPCC assessment process.
3. The social conditioning of climate science:
- The history of perceived anthropogenic climate changes.
- Post-normal science.

On the basis of my analysis I draw a couple of conclusions,
chief being that the process of climate science must be 
organized in a sustainable manner. This means that climate 
science should be conducted with a low sense of subjective 
passion; that climate science provides "if-then" answers to
questions society poses; that it presents to the society a 
broad range of possible policy responses and does not restrict
the range of policy options to a small corridor that appeals
to certain value-driven agendas.
The conditioning of science by the culture of its actors and 
society is unavoidable. However, the scientists can attempt 
to make such influences explicit by acknowledging and explicitly
reflecting on such influences, especially by engaging social 
scientists in the process of critical self-reflection. The 
Wegman-report claims that a major problem in studies such as
MBH would be an insufficient engagement by mainstream 
statisticians. I think a major problem with this study and its 
transformation into a policy-relevant issue is an insufficient 
comprehension of the social dynamics of the post-normal 
process of (not only) climate science.
There are three appendices to this document:
1. My responses to the "Boehlert"-questions given at the NRC 
hearing on March 2, 2006 in Washington.
2. A contribution to the debate about the "Barton-letters" on 
the "Prometheus"-weblog http://sciencepolicy.colorado.edu/prometheus/ 
dated July 8, 2005 
(http://sciencepolicy.colorado.edu/prometheus/archives/climate_
change/000486hans_von_storch_on_b.html)
3. An English translation of an article published in the German
weekly "DER SPIEGEL" (4/2005): von Storch and Stehr: A climate of
staged angst. 
(http://sciencepolicy.colorado.edu/prometheus/archives/climate_
change/000343a_climate_of_staged_.html)

Scientific aspects

How valid are the regression-type methodologies for reconstruction 
historical climates? 
The key statistical assumption of any of such methods is the 
uniformity of informational content in the proxies which are 
regressed on the climate variables (mostly temperature). In other 
words, are these data influenced by non-climatic variable factors 
(inhomogeneity), is the transfer function linking proxies and 
temperature constant in time (stationarity)? Likely, most if not 
all proxy data (tree rings, coral rings, vine harvests) suffer from 
some inhomogeneities and instationarities. This is unavoidable and 
has to be dealt with by using additional insight into the system, 
e.g. by data assimilation approaches combining limited theoretical 
(models) and empirical knowledge (uncertain data).
Regression-type models are designed so that they return only part 
of the full variability of the variable of interest, namely that 
part which can be traced back to the proxies. Not all of the 
variability can be accounted for in this way. The difference in 
variability of temperature and of proxy-derived temperature is 
dealt with by "scaling", i.e., by applying a suitable normalization. 
If "scaling" is used, then the basic principle of regression is 
violated, as the part of variability in the predictand (temperature), 
which can not statistically traced back to the predictor (proxy), is 
nevertheless related to predictor-variability. Scaling is useful, 
when the transfer function is not regression (screening of 
co-variability of two variables) but based on physical arguments.
Nevertheless, attempts like those by MBH are useful and should be 
explored. They may provide useful estimates. The problem with MBH 
was that the result was presented by the IPCC and others in a manner 
so that one could believe a realistic description of historical 
temperature variations had successfully been achieved. The NRC report 
published in June 2006 has made clear that such a belief was incorrect.

How relevant are these reconstructions for claims that we presently 
experience a climate change outside the range of what we consider as 
"normal" 
Whether the present climate is influenced by non-natural factors is 
answered through "detection" studies. Such studies are based on the 
insight that the predicted signal of human-caused climate change 
should emerge in most recent times from the natural variability. 
Second, one would expect it to manifest itself with a higher "than 
normal" rate of change. Thus, the signal is expected to be a rapid
warming in the most recent past. The method to test this hypothesis 
is to find out if we have a "steeper-than-normal" recent upward 
temperature trend. The hypothesis is not "we have a period which is 
warmer than ever in historical times". In that sense the claim 
whether the last decade is the warmest of the past millennium is not 
relevant to detection; the question is whether the recent rate of 
warming is markedly stronger than what has happened in the past.
The hypothesis is tested by framing the problem as a statistical 
test of a null hypothesis. The null hypothesis reads "the present 
trend is of natural origin". Then, one determines the range of 
trends consistent with natural variability - and rejects the null 
hypothesis (and accepts the hypothesis that the trends is not of 
natural origins) if the present trend is larger than, say, 97.5% 
of trends originating entirely from natural variability.
The crux of this approach is of course the determination of the 
range of trends which are observable under natural conditions. To 
do so, one may rely only on the instrumental period, which is 
contaminated by the expected signal and rather short, on 
multi-century reconstructions as MBH and on extended model 
simulations of undisturbed conditions. Obviously the determination 
of the range of "normal" trends is uncertain and absolute certainty 
can not be attained within a reasonable time. 
We1 have examined which range the different historical 
reconstructions suggest. To do so, the time series of reconstructions 
have been "modelled" as a long-memory process, and standard 
deviations of trends are derived. Here, the trend is defined as the 
difference of two 30 years means 100 years apart. Then these trends 
are determined from the instrumental record as given as multiples 
of the standard deviations derived from the different reconstructions.

The result is given in the diagram; the curves are all the same, but 
they differ in scale because of the unit of different standard 
deviations derived from the reconstructions given at the figure 
caption. The horizontal dashed lines mark 2, 2.5 and 3 standard 
deviations. Two standard deviations correspond to a risk of false 
rejection of the null hypothesis of 2.5%.
Obviously, in all cases, the critical 2-standard deviation mark is 
passed sometimes in the past decades; in case of MBH this happens 
very early, while in Moberg's more variable reconstruction at about 
1980. 
I conclude that the claim of "detection of anthropogenic climate 
change" is valid independently of which historical temperature 
reconstruction one chooses to believe in. 
It should also been taken notice that the claims of successful 
detection on non-natural warming trends and its attribution to 
chiefly elevated greenhouse gas concentrations in the atmosphere 
in the Third Assessment report were not based on the historical 
reconstructions but on the analysis of the instrumental temperature 
record as well as on numerical experiments with climate models. 

The process of achieving success of a scientific knowledge claim 
in the climate science community
A normal condition in the progress of science is that knowledge 
claims are accepted only after a "peer-review" process. The 
peer-review process attempts to assure that knowledge claims are 
consistent with the empirical evidence, and properly related to 
contemporary accepted knowledge claims, and that the methods are 
sound and are reproducibly described.  The "peer-review" process 
does not eliminate the possibility that new ideas are rejected 
since they may contradict contemporary, powerful but possibly 
false knowledge claims (see Ludwik Fleck's seminal book on 
"Generation of a Scientific Fact"). In order to minimize such a 
danger, the verdict of peer-reviewers should, to first order 
approximation, be independent of the persons involved in the 
review process. Nonetheless, the danger is that a few scholars 
may become powerful gatekeepers, for example as reviewers who 
are regularly called upon or as editors of scientific journals. 
The primary goal of such gatekeepers is to fend off publications 
which may contradict their own thinking, and not to ensure that 
only internally consistent and plausible publications reach the 
market of knowledge claims (i.e. scientific journals). 
Unfortunately this seems to have happened in the field of 
historical global climate reconstructions, where a small group of 
scientists has exerted an undue control of the entire field. 
Usually, a further mechanism more closely tied to the substance 
of research is used to quality-control scientific knowledge
claims, namely reproducibility. This mechanism has ceased to 
operate in some quarters of paleo-climate science, since some 
scientists consider "their" data as their personal property and 
not that of the scientific community, so that others are unable 
to challenge conclusions drawn from these data by analysing the 
raw data in their own manner. Although such secrecy is a very 
human trait it violates the norms of science. Even hostile 
competitors should have an opportunity to independently re-examine 
the empirical evidence for conclusions drawn by others, in 
particular when they become relevant for the policy domain. Data
must be become public; the methods employed must be described in 
algorithmic detail.
Another relevant aspect is the functioning of the two prestigious 
journals "Science" and "Nature". The journals enjoy high esteem 
within and outside of the scientific community as having the 
highest scientific standards, which is not always the case. The 
contents of Nature and Science also receive exceptional attention 
in the media world-wide. However, different from "normal" 
scientific journals, the editorial decision to accept a 
scientist's contribution to Science or Nature is also based on 
the newsworthiness of the research contribution. The presented 
results must not only be valid and innovative but must also be 
of interest for a wider community of readers. Such a criterion 
is reasonable from a economic point-of-view, but it clearly 
introduces a filter in what is reaching the public is not solely 
based on the scientific merit of research. Research results with
stronger media appeal fare better in this competition of 
scientific findings; results biased towards higher sensitivity 
to human interference are more interesting to a broad audience 
than findings that report low sensitivities. In addition, there 
may also be a bias towards certain authors, who are well known, 
because they enjoy public visibility, or command appealing 
writing skills, "sell" well. Sometimes such contributions are 
invited.
Another problem with the same journals is that their articles 
must be relatively short so that technical aspects cannot be 
described in any detail; indeed, the MBH publication was cursory 
on the methodical side - thus the statistical method, the 
validation and the reproducibility, have not been seriously 
subject to the review process. Ironically, after publication in 
"Nature" the method was considered "peer-reviewed" and thus 
valid. However, this was not the case, as the method had not
been properly described. 
The IPCC has different levels of operation - the generation of 
the technical chapters, which is done by a group of "lead 
authors", headed by "convening lead authors", and the process 
of arriving at a SPM (Summary for policymakers) and other 
overall assessment documents, which is done by the convening 
lead authors and representatives of the countries. 
How the selection process of lead and convening lead authors 
is done, I do not know - but it is clear that the "lead 
authors" are supposed to be experts in the field. This leads 
to the situation that the IPCC chapters are dominated by the 
authors of the most influential articles in their respective 
fields of research. Participation as a lead or convening lead 
author has the advantage that one can make sure that one's own
work is positively covered in the IPCC report. However, most 
lead and convening lead author excel as honest brokers, but
some level of gatekeeping may prevail. Indeed, the reputation
of the IPCC among scientist has increased to very high levels 
in the past years.
The IPCC procedure differs markedly from the procedure adopted
by the National Research Council assessment. In that case, a 
group of eminent scientists was chosen, who have contributed 
to the issue only little or not at all, but have a god 
understanding of the field as a whole. These scientists then 
invited a group of experts to present the different angles 
and knowledge claims. I consider the NRC procedure better in 
assessing the field of knowledge than the IPCC approach. It
may be, however, that the NRC approach can not be used for 
such a complex and large field, which the IPCC is covering.
In case of the MBH temperature reconstruction one should note 
that in the technical chapter of the TAR different 
reconstructions had been presented; it was the SPM and the 
synthesis report, where the range of reconstructions was 
reduced to just one, the MBH. It would be interesting to learn 
how this could have happened.

The social conditioning of climate science
Science is a social process, which, as all social processes, is 
conditioned by the culture of the actors. This does not mean 
that scientists would do their analysis irrationally or in a 
biased manner, but it means that our questioning may by guided 
by culturally constructed concerns and interests. Also, we may 
be convinced of the validity of some findings more easily if 
these findings are consistent with our prior lay-knowledge.

The history of perceived anthropogenic climate changes
It has often been claimed that anthropogenic climate change is 
a recent concept. This is incorrect. In the history of ideas of 
the past 1000 years, we2 have found a number of occasions when 
(western) people have used the concept to explain observed 
changes:
"During the last 20 years the concept of anthropogenic climate 
change has left academic circles and become a major public 
concern. Some people consider 'global warming' as the major 
environmental threat to the planet. Even though mostly 
considered a novel threat, a look into history tells us that 
claims of humans deliberately or unintentionally changing 
climate is a frequent phenomenon in Western culture. Climate 
change, due to natural and anthropogenic causes, has often 
been discussed since classical times. Environmental change 
including climate change was seen by some as a biblical mandate, 
to 'complete the Creation'. In line with this view, the prospect 
of climate change was considered as a promising challenge in 
more modern times. Only since the middle of the 20th century, 
has anthropogenic climate change become a menacing prospect. 
The concept of anthropogenic climate change seems to be deeply 
embedded in popular thinking, at least in Europe, which 
resurfaces every now and then after scientific discoveries. 
Also, extreme weather phenomena have in the past often been 
explained by adverse human interference."3

This finding is insofar relevant as it points out that we, as 
members of the western culture, are somehow prepared to accept
"anthropogenic influence" as an explanation for otherwise 
unexplainable events, such as a cluster of extreme events. Our 
common understanding is that such a human influence would be 
associated with negative impacts. This pre-conditioning may 
influence our process of drawing conclusions, in particular 
when we (scientists) deal with the problem of transferring 
scientific findings into the political arena.


Post-normal science.
Most of environmental science is what sociologists call 
"post-normal", i.e., loaded with high uncertainty on an 
issue of great practical importance. Climate change science 
is an example of such post-normal science.4
A characteristic of post-normal science is that the 
boundaries between science and value-driven agendas get 
blurred; that representatives of NGOs are considered to 
know better about the functioning and dynamics of systems 
than scientists; that parliamentarian committees delve 
into the technicalities of science; that amateurs engage 
in the technical debate: and that some scientist try to 
force "solutions" upon policymakers and the public. In 
such a situation it becomes entirely possible that 
individual scientists emphasize those insights which are 
assumed to influence certain policy decisions more 
forcefully, while downplaying others.
Typical for such a post-normal situation is the flooding 
of the media with books and movies which dramatize the 
issue. Recent examples include: The Day After Tomorrow, 
State of Fear, Satanic Gases, The Revenge of Gaia, and An 
Inconvenient Truth.
In this situation we need a discussion, not only among 
scientists about the role of science for the public, 
which must be the provisions of options for policy, not 
the narrowing of the range of options to satisfy different
worldviews. To limit the influence of non- or pre-scientific 
knowledge claims, social and policy scientists need to 
analyse the different processes in climate science, and the 
interdependence of culture, policy, politics, media and 
climate science. Even if science can never be fully 
"objective", it may nevertheless be possible to make climate 
science a considerably more objective practice than what we 
have in these days.


Appendices

(a) My answers to Chairman Boehlerts questions, given at the 
NRC hearing
What is the current scientific consensus on the temperature 
record of the last 1,000 or 2,000 years? What are the main 
areas of uncertainty and how significant are they?
  There is consensus on the "blade", but the claimed 
smoothness of the shaft is likely false.
  The main problem is the loss of information encoded in 
the proxy data and the shortness of the instrumental record 
for training the statistical models.
What is the current scientific consensus on the conclusions 
reached by Drs. Mann, Bradley and Hughes? What are principal 
scientific criticism of their work and how significant are 
they? 
Has the information needed to replicate their work been 
available? Have other scientists been able to replicate their 
work?
  There is no consensus on the claims (which?) made by MBH. The 
  main critique is that the method is suffering from a too large
  loss of variability on long time scales.
  No, the information required for replication was not made 
  available in a suitable manner. The original publication in 
  "nature" did not provide this information and was obviously 
  published without careful review of the methodology.
  Yes, the details of the method were finally determined, among 
  others by B�rger et al., who checked a wide range of 
  combinations of details - which all gave widely different 
  results.
How central is the debate over the paleoclimate temperature 
record to the overall consensus on global climate change? How 
central is the work of Drs. Mann, Bradley and Hughes to the 
consensus on the temperature record?
  The main conclusions about "detection and attribution" are 
  drawn from the instrumental record and models; the different 
  reconstructions do not contradict "detection".
  The MBH work is widely accepted as truth outside of people 
  directly engaged in the issue, because of a less than 
  satisfactory marketing by the IPCC. 


(b) My posting on weblog "Prometheus" July 08, 2005 on the 
"Barton letters"
My reaction to Rep. Barton's requests is split. In his five 
letters, he is asking for information from two different groups, 
namely institutions with reviewing responsibilities (IPCC, NSF) 
and individuals with scientific responsibilities (M, B and H). 
I find his inquiry of the performance of the institutions IPCC 
and NSF valid, but the interrogative questioning of the 
individual scientists is inadequate.
a) Scientists. The scientists have the task to be innovative, 
creative, to try new avenues of analysis and the like. They 
have the right to err, the right to suggest explanations and 
interpretations which may need to be revised at a later time. 
They should document what they have done, so that others can 
replicate.
However, this documentation often can not take the form of 
keeping runnable old codes of the applied algorithms, simply 
because the software is no longer consistent with quickly 
replaced hardware. For instance, most of the state-of-the-art 
coupled AOGCMs used in the mid 1990s are simply no longer 
available and running at, for instance, the German Climate 
Computer Center. After replacing a high performance computer 
with a new system, the standard model codes, including community 
models, need to be adapted to the requirements and possibilities 
of the new system, and the old code will often no longer run. 
This has nothing to do with the norms of the community but simply 
with technological progress. Also specific commercial libraries of
specialized algorithms may no longer be accessible. Data and codes 
written on old magnetic tapes or even floppies are usually no 
longer readable.
Therefore the documentation must take the form of a mathematical 
description of the algorithms used. This is in many if not most 
cases sufficient for replication. Also, the intention of 
replicability is not to exactly redo somebody's simulation and 
analysis, but to find the same result with a similar code and 
different but statistical equivalent samples. The problem is usually 
not that the codes contain errors (even if many of the more complex 
ones likely contain minor, mostly insignificant errors), but that 
specific elements of implementation and specific aspects of the 
considered sample of evidence will lead to conclusions, which do not 
hold if another sample is considered or a different but equally good
algorithm is employed. The reason is that we want to learn about the 
dynamics of the real world, and these insights should not depend on
random choices in sampling and implementation. We generally do not 
expect scientists to manufacture results, or that unintended but 
significant errors will affect the eventually published conclusions.
Having this situation in mind, I consider Rep. Barton's requests to 
the three scientists as inadequate and out-of-scale. However, the 
language used by Rep. Barton makes me perceiving this request as 
aggressive and on the verge of threatening.
The situation is different with the second groups of recipients, 
the:
b) "Reviewers". Reviewers have a different role, namely they shall 
make sure that the standards of scientific reporting are held up. 
They have to ensure that the proposed explanations are considered 
by independent experts as to whether the presented analysis seems 
valid and in principle reproducible. "Independent" means that the
reviewers have no vested interests for or against the case 
presented. In the conventional set-up these interests usually 
refer to academic schools of thought, but in the unfortunate,
post-normal case of climate science independence from the 
political utility of the case should be established.
In this case, I find the inquiry of Rep. Barton to be valid. The 
IPCC has failed to ensure that the assessment reports, which 
shall review the existing published knowledge and knowledge
claims, should have been prepared by scientists not significantly 
involved in the research themselves. Instead, the IPCC has chosen 
to invite scientists, who dominate the debate about the considered
issues, to participate in the assessment. This was already in the 
Second Assessment Report a contested problem, and the IPCC would 
have done better in inviting other, considerably more independent
scientists for this task. Instead, the IPCC has asked scientists
like Professor Mann to review his own work. This does not represent
an "independent" review.
The NSF seems to have failed to ensure that sufficient information
is provided about work done under its auspices.
Rep. Barton should also have asked the editors of "Nature", why 
the original manuscript was accepted for publication even though
the key aspect of replicability was obviously not met by the MBH
manuscript. Actually, MBH could not meet this condition because 
of the strict length limitation of that journal (nowadays one 
would ask for extensive Supplementary Online Material). One 
should ask why the manuscript was accepted nevertheless - and 
not, as in many other cases, the manuscript was recommended to 
be published in a "normal" journal without the severe length 
limitations. I believe the reasons for Nature were the journalistic 
reasons - namely the expected broad interest in the subject. One 
should also ask why after the critique von McIntyre and McKitrik 
only MBH got the opportunity for a correction of his paper, whereas 
the short manuscript of their opponents was rejected.
To conclude - the requests to M, B and H are not fair but may 
unfortunately lead to a repressive atmosphere within climate 
science; the requests to NSF and the IPCC, however, are 
appropriate, as these institutions may have failed in a primary 
task, namely to guarantee an open scientific discourse. And, 
Rep. Barton should have included the editors of Nature in his 
analysis.



A Climate of Staged Angst

By Hans von Storch and Nico Stehr 

The days are gone when climate researchers sat in their ivory 
towers packed to the rafters with supercomputers. Nowadays 
their field has become the stuff of thrillers, and they 
themselves have risen to take on the leading roles. The topic is 
so hotly contested, the prognoses so spectacular, that they are 
no longer merely the subject of media reports; now the 
specialists in staged apocalypse have moved in. Last year Roland 
Emmerich depicted a climatic collapse provoked by humankind in 
his film "The Day After Tomorrow." Since last week the 
belletristic counterpart has been available in German bookstores: 
the novel "State of Fear," by the best-selling author Michael
Crichton.
The thriller is about the violent conflict between sober 
environmental realists and radical environmental idealists. For 
the idealists, the organized fear of abrupt climate change serves
as a handy weapon. They interpret every somehow unusual weather 
event as proof of anthropogenic global warming. "You have to
structure your information so that it's always confirmed, no 
matter what kind of weather we have," the P.R. consultant for 
the environmentalist organization advises. The realists, who 
protest that the evidence that human activity has increased 
meteorological extremes is thin, are fighting a losing battle. 
Their dry scientific arguments are unable to gain any ground 
against the colorful, horrific visions of the climate idealists.
Film and novel have certain aspects in common. Where Emmerich 
holds out the prospect of a threatening climate catastrophe, the
book prophesies an economic collapse. In both cases, greenhouse 
gases produced by humankind are the culprit - in the film, 
because the emissions themselves are too much; in the book, 
because the fear of them is. The idealists are so obsessed with
their mission that ultimately, in order to rouse the public, they 
themselves bring about the foretold catastrophes.
Despite a good deal of factually untrue - and thus all the more
striking - compression, Crichton has quite correctly observed the 
dynamic of the paths of communication among scientists, 
environmentalist organizations, the state and the civilian 
population. For there is indeed a serious problem for the natural
sciences: namely, the public depiction and perception of climate 
change. Research has landed in a crisis because its public actors
assert themselves on the saturated market of discussion by 
overselling the topic.
Climate change of man-made origin is an important subject. But
is it truly the "most important problem on the planet," as an 
American senator claims? Are world peace, or the conquest of 
poverty, not similarly daunting challenges? And what about 
population growth, demographic change or quite normal natural 
disasters?
In the U.S., only a very few remain interested in the greenhouse
effect. At the end of the 1980s, the situation was still different. 
That was the era of the great drought of 1988, the Mississippi
flood of 1993, and the climate capers ought by rights to have taken
off in earnest from that point. But that never happened in the U.S., 
and interest petered out. According to a survey by the CBS television
network in May 2003, environmental problems were no longer ranked 
among the six most important subjects; and even within environmental
problems, the topic of climate came in only in seventh place. In 
Germany, so far, things are still seen differently. But for how much 
longer?
In order to keep the topic of "climate catastrophe" - a concept 
nonexistent outside the German-speaking world, by the way - 
continually in the public eye, the media feel obligated, exactly
like the protagonists in Crichton's thriller, to keep framing the 
topic "a bit more attractively." At the beginning of the 1990s - 
severe storms had just swept through the country - one could read and 
hear in the German media that storms were due to become ever more 
severe. Since then, storms have become rarer in northern Europe. But
no notice is taken of this. The fact that barometric fluctuations in
Stockholm have shown no systematic change in the frequency and 
severity of storms since Napoleon's time is passed over in silence.
Instead, there is now talk of heat waves and floods. Very much in 
the style of Crichton's instigators of fear, the story is now that 
all manner of extreme events are on the increase. Thus even drought 
in Brandenburg and deluge on the Oder fit the picture without 
apparent contradiction.
Add to this - besides normal floods and storms - other, more 
dramatically threatening, scenarios: the reversal of the Gulf 
Stream and the resultant cooling of large areas of Europe, for 
instance, or even the rapid melting of the Greenland ice pack. 
The question has already been publicly raised whether perhaps even 
the Asian tsunami can be attributed to the disastrous effects of 
human activity.
This will not be able to hold the public's attention for long. Soon 
people will have become accustomed to these warnings, and will 
return to the topics of the day: unemployment and Hartz IV, Turkey's 
entry to the E.U. or whether Borussia Dortmund can avert disaster on 
the soccer field and in the boardroom. Thus we will see firsthand 
how the prophets of doom will draw the climatic dangers in even more 
garish colours. The terrifying visions to haunt the future can 
already be guessed at: the breakup of the west Antarctic shelf ice, 
which will cause the water level to rise much more rapidly, and after 
a few decades of uncontrolled carbon dioxide emissions, an abrupt rise 
in temperatures, giving us a deadly atmosphere like that of Venus. 
Prospects such as these have long been in the public eye; can they not 
compete effortlessly with Emmerich's Hollywood images?
The costs of stirring up fear are high. It sacrifices the otherwise 
so highly valued principle of sustainability. A scarce resource - 
public attention and trust in the reliability of science - is used up 
without being renewed by the practice of positive examples.
But what do climate researchers themselves think, how do they deal 
with the media and the population?
Public statements by noted German climate researchers give the 
impression that the scientific bases of the climate problem have 
essentially been solved. Thus science has provided the prerequisites 
for us now to react appropriately to the goal; meaning, in this case, 
to reduce greenhouse gas emissions as much as possible.
This does not at all reflect the situation in the scientific 
community. A considerable number of climatologists are still by no 
means convinced that the fundamental questions have been adequately 
dealt with. Thus, in the last year a survey among climate 
researchers throughout the world found that a quarter of the 
respondents still harbor doubts about the human origin of the most 
recent climatic changes.
The majority of researchers are indeed of the opinion that global 
climate change caused by human activity is occurring, that it 
will accelerate in the future, and that it will thus become more 
readily apparent. This change will be accompanied by warmer 
temperatures and a higher water level. In the more distant future, 
that is, in about 100 years, a considerable increase of atmospheric 
greenhouse gases is foreseen, together with an increase in heavy 
precipitation in our latitudes; in some regions there could be 
more powerful storms, in others weaker ones.
But again and again, there are scientists to whom, true to the 
alarmists' maxim in Crichton's book, this does not sound dramatic 
enough. Thus, more and more often they connect current extreme 
weather events with anthropogenic climate change. To be sure, this 
is usually carefully formulated; interviews sound something like 
this: "Is the flooding of the Elbe, the hurricane in Florida, this 
year's mild winter evidence for the climate catastrophe?" Answer: 
"That's scientifically unproven. But many people see it that way." 
Neither of these statements is false. In combination, however, 
they suggest the conclusion: Of course these weather events are 
evidence. Only no one dares to say this explicitly either.
The pattern is always the same: the significance of individual 
events is processed to suit the media and cleverly dramatized; 
when prognoses for the future are cited, among all the possible 
scenarios it is regularly the one with the highest rates of 
increase in greenhouse gas emissions - and thus with the most 
drastic climatic consequences - that is chosen; equally plausible 
variations with significantly lower emission increases go unmentioned.
Whom does this serve? It is assumed that fear can motivate listeners, 
but it is forgotten that it mobilizes them only in the short term. 
Climatic changes, however, demand long-term reactions. The effect on 
public opinion in the short view may indeed be "better," and thus may 
also have a positive effect on reputation and research funding. But 
in order for this to function in the long run, each most recent claim 
about the future of the climate and of the planet must be ever more 
dramatic than the previous one. Once apocalyptic heat waves have been
predicted, the climate-based extinction of animal species no longer 
attracts attention. Time to move on to the reversal of the Gulf
Stream. Thus there arises a spiral of exaggeration. Each individual 
step may appear to be harmless; in total, however, the knowledge 
about climate, climate fluctuations, climate change and climatic 
effects that is transferred to the public becomes dramatically 
distorted.
Sadly, the mechanisms for correction within science itself have 
failed. Within the sciences, openly expressed doubts about the 
current evidence for climatic catastrophe are often seen as 
inconvenient, because they damage the "good cause," particularly 
since they could be "misused by skeptics." The incremental 
dramatization comes to be accepted, while any correction of the 
exaggeration is regarded as dangerous, because it is politically 
inopportune. Doubts are not made public; rather, people are led 
to believe in a solid edifice of knowledge that needs only to be 
completed at the outer edges.
The result of this self-censorship in scientists' minds is a deaf 
ear for new and surprising ideas that compete with or even 
contradict conventional patterns of explanation; science 
degenerates into being a repair shop for popular, politically 
opportune claims to knowledge. Thus it not only becomes sterile; 
it also loses its ability to advise the public objectively.
One example of this is the discussion of the so-called "hockey 
stick," a temperature curve that allegedly depicts the development 
over the last 1000 years, and whose shape resembles that of a 
hockey stick. In 2001 the Intergovernmental Panel on Climate 
Change, the committee of climate researchers appointed by UNO, 
rashly institutionalized this curve as the iconic symbol for 
anthropogenic climate change: At the end of a centuries-long 
period of stable temperatures, the upward-bent blade of the 
hockey stick represents the human influence.
In October 2004, we were able to demonstrate in the scientific 
journal "Science" that the methodological bases that led to this 
hockey-stick curve are mistaken. We wanted to reverse the spiral 
of exaggeration somewhat, without also relativizing the central
message - that climate change caused by human activity does indeed 
exist. Prominent representatives of climate research, however, did 
not respond by taking issue with the facts. Instead, they worried 
that the noble cause of protecting the climate might have been 
done harm.
Other scientists lapse into a zeal reminiscent of nothing so much 
as the McCarthy era. For them, methodological criticism is the 
spawn of "conservative think tanks and propagandists for the oil 
and coal lobby," which they believe they must expose; dramatizing 
climate change, on the other hand, is defended as a sensible means 
of educating society.
What is true for other sciences should also hold for climate 
research: Dissent is the motor of further development, Differences 
of opinion are not an unpleasant family affair. The concealment of 
dissent and uncertainty in favor of a politically good cause takes 
its toll on credibility, for the public is more intelligent than 
is usually assumed. In the long term, these allegedly so helpful 
dramatizations achieve the opposite of that which they wish to 
achieve.
By doing so, however, both science and society will have wasted 
an opportunity.

Hans von Storch, 55, heads the Coastal Research Institute of the 
GKSS Research Centre in Geesthacht, Germany; he is considered 
leading experts statistical analysis of climatological data and 
simulations. Together with Nico Stehr, 62, sociologist at the 
Zeppelin University in Friedrichshafen, Germany he has conducted 
ongoing research into the public perception of climate change.

Translated by Paul Malone

First published in Der Spiegel No. 4, 2005.




	MR. WHITFIELD.  Thank you, Dr. von Storch, and
	Mr. McIntyre, you are recognized for 5 minutes.
MR. MCINTYRE.  Good afternoon, Mr. Chairman and members of the 
committee.  My name is Steve McIntyre.  I appreciate the 
invitation to appear today to discuss my research coauthored with
Ross McKitrick of the University of Guelph which in part led to 
today's meeting.
	I have three main messages.  First, little reliance can 
	be placed not only the original Mann reconstruction, 
	various efforts to salvage it, or similar multi-proxy 
	studies even ones which did not use Mann's methodology. 
	Second, peer review as practiced by academic journals is 
	not an audit but something much more limited. In turn, 
	scientific overviews such as the ones produced by IPCC or
	even by the NAS panel are based almost entirely on 
	literature review rather than independent testing.  Third, 
	there is already an existing data archive which is 
	excellent, but in order to make it work scientists actually 
	have to archive their data and code.  This is not done 
	consistently in the paleoclimate community and it makes 
	replication virtually impossible in many cases.  Much of 
	this work is funded by the U.S. Federal government and 
	some very simple administrative measures under existing 
	policies could alleviate many of the problems.
	In the two reports, only one topic was specifically 
	audited in the sense of independent testing as opposed to 
	literature review, and that was simply whether Mann's 
	method was biased towards producing hockey stick-shaped 
	series.  Both reports verified this hotly contested result.  
	Both panels agreed with varying emphasis that no confidence 
	could be placed on reconstructions prior to 1600 and that 
	Mann's statistical methods were unsatisfactory.  The Wegman 
	report considered how such an error could have remained 
	undetected.  In addition to their comments, an important 
	reason that the IPCC does not carry out independent tests.
	Some comments of Dr. Bloomfield's at the NAS press conference 
	may lead people to believe that a hockey stick could be 
	obtained from a simple average of all MBH proxies.  This is 
	simply not the case as you see by the graph on both screens.  
	The NAS panel illustrated several other reconstructions but
	their consideration was merely a literature review.  They 
	did not attempt to replicate or audit these other studies as 
	I have tried to do.  Each one has replication problems.  One 
	of the criticisms of the Mann study recognized by the NAS 
	panel was its use of bristle cones and closely related 
	foxtails, a flawed proxy which the panel said should be 
	avoided.  However, they did not assess this.  The impact of 
	not using bristle cones can be substantial.  Removal of merely 
	two bristle cone series changes relative medieval modern levels 
	in the Crowley and Lowery reconstruction that was shown to you 
	earlier.  The panel noted the so-called divergence problem in 
	which temperatures in the last half of the 20th Century 
	increase while tree ring widths and densities decrease.  They 
	offered no solution other than reduced confidence, but the 
	problem is worse.  How can we even trust the shape of the 
	curve in previous warm periods if they miss the present one?  
	Bias sampling can arise not simply from Mann's principal 
	component methods, but by non-random and biased selection of 
	small samples.  In this graph shown here, even the selection 
	of a single site, of a different version from a single site 
	can have a dramatic impact on a worldwide reconstruction.  
	Here different versions impact the Briffa 2000 reconstruction 
	and all but one subsequent reconstruction shown in the 
	various spaghetti graphs.  The issue of the polar Urals is 
	substantive.  Naurzbaev et al., which included Mann's coauthor 
	Hughes, whose methods were cited by the NAS panel with a 
	approval, concluded that medieval summer temperatures in this 
	area were over 2.3 degrees Centigrade warmer than at present.
	The Wegman reported noted pervasive problems in paleoclimate 
	research practices.  A simple policy shown here already in 
	existence at the American Economic Review and other journals 
	and in fact a policy introduced by Dr. Bernanke, presently 
	Chairman of the Federal Reserve System, would alleviate many 
	of these problems.  There is no reason for journals not to 
	adopt similar rules for paleoclimatology where data sets are 
	similar in size and scale to many econometric studies.  In 
	fact, the 1991 policy statement of the U.S. global change 
	research program already requires data archiving and many 
	agencies such as NASA have complied with these policies.  
	However, the National Science Foundation does not and a senior 
	NSF official wrote to me saying that dissemination of data was 
	merely up to the professional judgment of the researchers.  
	Ironically, even the NAS panel relied heavily on unarchived 
	data.  The Department of Energy itself does not comply.  It 
	funded the development of the well-known CRU temperature series
	used by IPCC but their agreements failed to ensure that even 
	DOE has access to the supporting data.
	Nothing that I say here should be construed as diminishing the 
	seriousness of climate change as public issue.  It is precisely 
	because it is a serious issue that policymakers are entitled to 
	the best possible information.  You should not receive incorrect
	confidence assessments as happened with the hockey stick.  You 
	should discourage practices that interfere with efforts to 
	verify results.
	Finally, at the NAS press conference, when asked about 
	overselling of the hockey stick, panelist Cuffy said that the 
	IPCC sent a very misleading message through its prominent use. 
	Yet IPCC procedures which permitted this remain unchanged for 
	the upcoming fourth assessment report.
	Thank you very much.
	[The prepared statement of Mr. Stephen McIntyre follows:]


PREPARED STATEMENT OF STEPHEN MCINTYRE, TORONTO, ONTARIO, CANADA

SUMMARY

1. little reliance can be placed on the original MBH reconstruction, 
various efforts to salvage it or similar multiproxy studies, even 
ones which do not use Mann's principal components methodology;
2. peer review as practiced by academic journals is not an audit, 
but something much more limited. Scientific overviews, such as 
ones produced by IPCC or the NAS panel, are nearly entirely based 
on literature review rather than independent due diligence. 
3. much work in dispute is funded by the U.S. federal government. 
Some very simple administrative measures under existing policies 
could alleviate many of the replication problems that plague 
paleoclimate.

TESTIMONY
Good morning, Mr Chairman and members of the Committee. 
My name is Stephen McIntyre. I appreciate the invitation to appear 
today to discuss my research, coauthored with Ross McKitrick of the 
University of Guelph. Our publications led in part to the reports of
the NAS panel and the Wegman committee.
A year ago, the University Corporation of Atmospheric Research (UCAR) 
issued a national news release stating that our "highly publicized 
criticisms of the MBH graph are unfounded." Sir John Houghton, 
co-chair of IPCC, gave evidence to a Senate committee, stating that 
our results had been shown to be "largely false". The situation today
is different as both the NAS and Wegman reports have recognized our 
major findings while drawing different conclusions on their impact.
I would like to convey three main messages today:
1. little reliance can be placed on the original MBH reconstruction, 
various efforts to salvage it or similar multiproxy studies, even ones 
which do not use Mann's principal components methodology;
2. peer review as practiced by academic journals is not an audit, but 
something much more limited. Scientific overviews, such as ones 
produced by IPCC or the NAS panel, are nearly entirely based on 
literature review rather than independent due diligence. 
3. much work in dispute is funded by the U.S. federal government. Some 
very simple administrative measures under existing policies could 
alleviate many of the replication problems that plague paleoclimate. 
In the NAS and Wegman reports, only one topic has been specifically 
"audited" - in the sense of carrying out independent simulations as 
opposed to review of previous literature:
* Mann's principal component method is biased towards producing 
hockey stick shaped series.
Both audits verified this result, first published by us, but hotly 
contested for the past two years. Both panels agreed (with varying 
emphasis) that MBH confidence claims were incorrectly calculated, 
indeed that no confidence intervals prior to 1600 could be calculated 
and that MBH statistical methods were unsatisfactory.
The Wegman report considered why such an error could have remained 
undetected in such a prominent study, an issue not considered by 
the NAS panel. In addition to their comments, I note that IPCC does
not verify information from the scientific literature.
The NAS panel also endorsed our important criticism of MBH dependence
on proxies known not to be temperature proxies, agreeing that 
bristlecones should be avoided.
The NAS panel cited several other reconstructions, but their 
consideration was merely a literature review. They did not attempt to 
replicate or audit these other studies and cannot vouch for them. 
Having examined most of them closely, I do not believe that any of 
them provide robust or reliable information on relative medieval-
modern levels.
For example, some comments of Dr Bloomfield's at the NAS press 
conference may lead people to believe that a hockey stick could be 
obtained from a simple average of all 415 MBH proxies. This is not 
the case, as shown in Figure 1 below.

Figure 1. Top - Average of all 415 MBH proxies; bottom - MBH 
reconstruction.

The NAS panel illustrated four other multiproxy studies, as shown in 
Figure 2 below.  However, all four use bristlecones or closely-related 
foxtails. The panel did not analyse the impact on each study of 
avoiding bristlecones, as they elsewhere recommended. 


Figure 2. Excerpt from figure S-1 of NAS panel report

The impact of avoiding bristlecones in accordance with the NAS 
recommendation can be substantial - as shown in Figure 3 for Crowley 
and Lowery 2000, where the removal of two bristlecone series changes 
relative medieval-modern levels. 


Figure 3. Left - Excerpt from Crowley (2000); right - replication 
with red showing effect without bristlecones and without instrumental 
splicing.

The NAS panel noted the so-called "Divergence Problem", in which 
temperatures in the last half of the 20th century increase, while 
tree ring widths and densities decrease, demonstrated here for a 
rare large-sample (387) study of "temperature-sensitive" sites 
[Briffa et al 1998]. NAS offered no solution other than reduced 
confidence. But the problem is worse: how can we even trust the 
shape of the curve in previous warm intervals, if they miss the 
present one? 

Figure 4. Ring widths and density from Briffa et al 1988.

Biased sampling can arise not simply from Mann's principal 
component methods, but from non-random and biased selection of 
small samples. If you "mine" or "snoop" a network of red noise 
looking for what appear to be "temperature-sensitive" trends, 
an average of the picks will also yield a hockey stick shaped 
series. The Wegman report shows evidence of non-random picking. 
While the NAS panel noted the potential impact of inclusion/
exclusion of even individual series, they did not investigate it. 
Here is an important example that affects multiple studies. The 
first Briffa version of the Polar Urals series said that the 
early 11th century was among the coldest of the millennium; 
updated sampling in 1998 showed the opposite, but Briffa did not 
report it. Instead he substituted another series from a site 70
miles away with a hockey stick shape. This substitution had a 
dramatic impact on the medieval-modern relationship in the Briffa 
(2000) reconstruction and nearly all other subsequent studies.


Figure 5. Left - three different versions of Polar Urals series. 
Top - from Briffa et al 1995; middle - from Esper et al 2002 (the 
only use of this version); bottom - the version in Briffa (2000) 
and subsequent studies other than Esper et al 2002.  Right: the 
impact on the reconstruction in Briffa (2000). Black - Briffa 
(2000) version; red - using Polar Urals update. . All series in 
standard deviation units and 21-year gaussian smooth.

In our NAS presentation, we cited Naurzbaev et al 2004 (including 
MBH co-author Hughes) as offering a promising new line of handling 
tree ring data. NAS cited this with approval, but did not report 
their conclusion that medieval summer temperatures were over 2.3 
deg C warmer or that medieval treelines in the Polar Urals (and 
elsewhere) were higher than modern treelines.

Figure 6. Treelines at Polar Urals site (Shiyatov 1995).

While the NAS panel did not address the issue of archiving, other 
than in generalities, the Wegman report noted pervasive problems 
in paleoclimate research practices. A simple policy - already in 
existence at the American Economic Review and other journals - 
would alleviate many of these problems.  There is no reason not 
to require similar rules for paleoclimatology, where data sets and 
code are similar in size and scale.
Submitters should be aware that the Editors now routinely require, 
as a condition of publication, that authors of papers including 
empirical results (including simulations) provide to this office, 
in electronic form, data and code sufficient to permit replication. 

To the extent that senior policy-makers have previously turned 
their attention to the matter, the 1991 Policy Statement of the 
U.S Global Change Research Program already requires data archiving 
after a limited period of exclusive use and, in 1997, provided 
recommended language for agencies to implement in grant agreements. 
Many agencies (e.g. NASA) have complied with these policies.
The overall purpose of these policy statements is to facilitate 
full and open access to quality data for global change research. 
They ...represent the U.S. Government's position on the access to 
global change research data....
For those programs in which selected principal investigators have 
initial periods of exclusive data use, data should be made openly 
available as soon as they become widely useful. In each case the 
funding agency should explicitly define the duration of any 
exclusive use period. 

	
Yet when I copied NSF on a request for data necessary to replicate 
key MBH results, a program officer not only refused to support the 
request, but intervened to counsel Mann against supplying the data.
Dr. Mann and his other US colleagues are under no obligation to 
provide you with any additional data ... His research is published 
in the peer-reviewed literature which has passed muster with the
editors of those journals and other scientists who have reviewed 
his manuscripts.  You are free to your analysis of climate data 
and he is free to his.

 Subsequently, a senior NSF official said that dissemination of 
 data was merely up to the "professional judgement" of the 
 researchers. Ironically, the NAS panel relied heavily on 
 unarchived data.
In general, we allow researchers the freedom to convey their 
scientific results in a manner consistent with their professional 
judgement... 


The Department of Energy funded the development of the well-known 
CRU instrumental temperature series, used by IPCC and others.  In 
response to a request for supporting data, Philip Jones, a prominent 
researcher said: 
We have 25 or so years invested in the work. Why should I make the 
data available to you, when your aim is to try and find something
wrong with it? 

Although DOE had funded the collection, their past and present grant
agreements had not ensured that even DOE had access to the supporting 
data and they said that they were unable to assist.
Phil [is] not obligated under the conditions of past or present DOE 
proposal awards to provide these items to CDIAC.  I regret we cannot
furnish the materials you seek 

In conclusion, I re-iterate that you can place little reliance on any
existing multiproxy study; that you need to distinguish between the 
limited due diligence of journal peer review and the substantive due 
diligence of an audit; and that simple administrative measures can 
substantially improve paleoclimate research practices.
Both the NAS report and Wegman reports are valuable studies by 
accomplished authors. Nothing that I say here should be construed as 
diminishing the seriousness of climate change as a public issue. It 
is precisely because it is a serious issue that policy-makers are 
entitled to the best possible information and should ensure that data, 
code and methods be accurately and completely archived and discourage
practices that interfere with scientific reproducibility. 

References: 
See NAS Panel report.

	MR. WHITFIELD.  Thank you, Mr. McIntyre, and at this time I
	am going to recognize the full committee Chairman, Mr. Barton, 
	for 10 minutes.
	CHAIRMAN BARTON.  Thank you.  I want--let me thank Ms. Baldwin
	before she leaves.  She and Mr. Inslee and Mr. Stupak have been
	here the entire time and I think they need to be given 
	accolades.  Mr. Whitfield and I almost have to be here but
	they don't, so we appreciate you all's attendance.  I want to 
	thank these witnesses for waiting 5 hours to testify.  That 
	shows a little bit of fortitude on your part.
	My first question goes to you, Dr. Karl.  Talking about the 
	peer review and the acceptance, if I were to ask Mr. Inslee and
	Mr. Stupak and Ms. Baldwin to review the work of this committee 
	in this Congress and then turn around and ask Mr. Whitfield and
	Mr. Walden and Mr. Shimkus, I would probably get two radically 
	different assessments.  Same body of work but my friends on the
	Democrat side would view the accomplishments in all probability
	substantially different than my colleagues on the Republican 
	side because both are biased in an open and honest way and have
	a different worldview on some issues, not on all issues.  So it 
	shouldn't be surprising if the same people that Dr. Wegman calls
	a social network and are interacting all the time that they view 
	positively the output, should it?
	DR. KARL.  Are you asking about whether or not the review 
	process is skewed?
	CHAIRMAN BARTON.  No, I am just asking you to comment because I
	will stipulate that everybody in the climatology community, the 
	environmental community, have got good faith and are trying to 
	do what they think is right for the world.  I am not--but there 
	are biases on both sides, and one of Dr. Wegman's criticisms, 
	and Dr. McIntyre reinforces it, is that you are not really 
	getting independent review, and there are cases, as Dr. Crowley
	pointed out, there may not be anybody that can be independent 
	because they don't understand it.  If I want somebody to
	interview Albert Einstein's work in the 1930s, there probably 
	weren't two or three people in the world that even knew what 
	he was talking about, so you do get that, but what happened 
	with Dr. Mann's study in 1998 was that it was accepted very 
	quickly as kind of the gold standard and it was given a 
	literary review, but it really wasn't given an independent
	scientific statistical review.  It was just accepted.  And 
	unless Dr. McIntyre is not being true, some of these other 
	studies that have come out that Dr. Crowley referred to, he
	used the same data sets and the same modeling or something 
	that is very close to it.  So how can us poor mortals that 
	have to make the policy decisions know what to believe when 
	the so-called scientific community could be portrayed as 
	scratching each other's back?  I mean, I am not trying to be 
	mean about it.  You know, I just am kind of puzzled.
	DR. KARL.  I mean, I can tell you the process that we use in 
	IPCC.  It may shed some light on it.  In the IPCC report, 
	each of the lead authors are asked to assess the published 
	literature up until a certain time after which no more new 
	material can be considered and what lead authors do is take a 
	look at that material and try to write up their consistencies 
	among what has been published, inconsistencies, what is 
	available today compared to what was available during either 
	the previous IPCC report or previous to that.  Having done 
	that, those writings then are subjected to international 
	review.  Anyone and everybody is open to review to report and 
	the process takes place over several years.  So there is ample
	time, ample review time--
	CHAIRMAN BARTON.  But do they really review it?  Again, I am
	not saying that your folks don't make a good-faith effort, but
	it is just like my analogy.  If I asked Mr. Whitfield, who is 
	a subcommittee Chairman because I appointed him subcommittee 
	Chairman as Chairman, if I say Ed, could you review my 
	performance as chairman of the full committee, I bet he is 
	going to give me a pretty high performance rating.  Now, on 
	the other hand, if I asked Mr. Inslee to review my performance
	as full committee Chairman, and I have consistently opposed 
	his amendments and I have consistently made life difficult for 
	him, which is not true but let us assume that it is true, he 
	is not going to rate me the same.  In all probability, Jay 
	Inslee is going to be more independent and objective than
	Ed Whitfield, and they are both good people.  But one of them 
	is more dependent on me, interacts more, benefits more with
	that interaction than the other and it appears to me that what
	Dr. Wegman and Mr. McIntyre are saying is, it may be because
	there are just not enough experts, it may be for any number of
	reasons, but a very small set of people review each other's
	work and lo and behold, they all come to the same conclusions.
	Now, we didn't put it into the record, but in 1975 we have the 
	Newsweek story about the meteorologists all being unanimously 
	in agreement that the world is in a world-cooling period and 
	it has catastrophic consequences and there was unanimous 
	agreement.  It was la di la di da.  Those were meteorologists. 
	Now, that is 31 years ago.  The world has changed.  We are 
	now worried about global warming but it the same thing.  You 
	know, I am not qualified to say whether the conclusions are 
	right or wrong.  I agree with what Dr. Wegman said and 
	Dr. North said, that--I can't conclusively say what is causing 
	it.  I can admit that the statistical record in the last 150
	years that the temperature is going up, but I would like to 
	see the scientific community self-regulate itself a little bit
	better so that when you have these statements like Dr. Mann 
	made that the 1990s were the warmest period in 1,000 years and 
	1998 is the warmest year in 1,000 years, that you can replicate
	that with statistically valid modeling technique that is open 
	to the public and everybody takes their shot at.  I think we
	have pretty conclusively proven today that that is not the 
	case, at least in that study.  That is not the case.  So that
	is my question to you, what can the scientific community do 
	to give us more certainty or more reliability that the 
	conclusions of these studies are really based on fact and not
	on opinion.
	DR. KARL.  I suspect, and I don't know for sure, but if you 
	request the records from the IPCC Bureau, for example, you 
	could--because it is public--you could get available the 
	disciplines of the individuals who commented on that report 
	and I note there is an IPCC report going on now, and that may 
	be a way for this committee to try and see the breadth and 
	scope of--
	CHAIRMAN BARTON.  Well, are you willing to recommend that--one 
	of the recommendations of Dr. Wegman is that the data be 
	publicly available?  Is that something that you would
	support?  Because we have apparently had a real problem with 
	Dr. Mann, getting his data and, it has been federally 
	funded.  I think it should be available, that anybody who 
	has the scientific ability and the mathematical ability to 
	study it, study it.  Do you agree with that?
	DR. KARL.  Yes.  Our Center actually houses the Paleoclimate
	World Data Center and we actually encourage researchers to 
	archive their data, not the actual proxy itself like the 
	tree ring or the ice core but the data from which they are 
	derived.  We are fairly successful in many instances, but I 
	am sure there is a number of instances where we don't have 
	data simply because of its significant investment on both 
	the PI's time and--
	CHAIRMAN BARTON.  And either Dr. North--I think Dr. North's
	report, or it may have been Dr. Wegman's, says there are 
	only 30 of these data sets in existence right now, that 
	there are a fairly limited number of data sets.  So we are 
	basing a lot of decisions on a fairly narrow band.
	Let me ask you something, Mr. McIntyre.  Since you had the 
	gumption to criticize Dr. Mann, how have you been received 
	in this community.  Are people patting you on the back and 
	inviting you to their Christmas party and saying right on,
	way to go, we really appreciate it, or are they kind of 
	giving you the cold shoulder and ask why the hell you did
	what you did?
	MR. MCINTYRE.  I would say cold shoulder would be 
	overstating the friendliness of it.  I would say that I
	have been reviled and--
	CHAIRMAN BARTON.  And so your skepticism for scientific 
	truth has not been welcomed with open warms.  Is that a 
	fair statement?
	MR. MCINTYRE.  I would say it has been an uphill fight.  
	Having said that one finds certain allies and certain 
	moments of comfort.  I mean, quite frankly I could
	understand why there would be some reluctance to take the
	claims seriously at the beginning.  That is one of the 
	reasons why I archived the source code and calculations 
	so that people could replicate it.  Aside from the fact 
	that I think it is something that should be done anyway,
	but my position was if anybody thinks that my results are 
	wrong, then I would like to know.  I would like to be the
	first person to know rather than the last person to know,
	and--but I--for example, the University Corporation of 
	Atmospheric Research put out a national press release 
	saying that all our claims are unfounded.  Sir John
	Houghton, co-chair of IPCC, testified to a Senate 
	committee that our claims were false.  So while I would
	say not all of our claims have been acknowledged, some of
	them have.  Both of these reports have certainly endorsed 
	a finding on methodology that surprised people and so, I 
	feel a little more comfortable now.  Also, some people have 
	been very generous and welcoming.  Dr. von Storch has
	encouraged me both publicly and privately.
	CHAIRMAN BARTON.  Dr. Crowley, this might be my last 
	question.  You mentioned in your oral statement--I didn't 
	see it in your written statement but it may have been 
	there--that there have been problems in the past with 
	correlation of current temperature readings and their 
	consequences with satellite readings and that those 
	correlations are much better today.  Is that true?  Did I--
	DR. CROWLEY.  Yes, that is true.
	CHAIRMAN BARTON.  Now, my understanding is that what 
	changed is that we have gone back and reprogrammed the 
	software on the satellites so that they will conform with 
	the model predictions.  Do you agree or disagree with that?
	DR. CROWLEY.  I completely disagree with that.
	CHAIRMAN BARTON.  Can you push your--I don't know that your 
	microphone is on.  You said--I think you said--
	DR. CROWLEY.  I disagree with you.  It is not the case of 
	trying to get it to conform to model predictions.  In fact,
	it stuck out like sore thumb for 10 years.  The climate 
	community took it very seriously as a disagreement and 
	pondered over it and there was eventually a comparison
	between two different groups of satellite analysts in 
	which they found a programming error in one of the
	algorithms for reducing the data that gave the differences 
	in the trends because this other group actually had gotten 
	a bigger trend in the satellite data than the one that 
	John Christy at University--
	CHAIRMAN BARTON.  Do you think that that disagreement is 
	worthy of being pursued by this subcommittee?
	DR. CROWLEY.  Well, what has happened is that the
	disagreement has diminished to the point where I am not 
	sure it is worth the subcommittee's effort to inquire. 
	It has been found to be a programming error, and an 
	innocent one but that happens when you are working with
	satellite or any other thing.  It just took a long time--
	CHAIRMAN BARTON.  Do you consider Dr. Mann's methodology 
	a programming error?  If you were Dr. Mann and--
	DR. CROWLEY.  No, because I don't think he actually
	wrote--I don't think his programs--when it is a programming
	error, it is like a coding error or something.  I think 
	that there is a methodological error, okay.  There is a
	difference between, as you know, since you took programming,
	between the--you can program a methodology that could be 
	wrong, okay.  So I don't think it was programming.  I 
	think it was a methodological error.
	CHAIRMAN BARTON.  Well, my time--
	DR. CROWLEY.  Not a--yeah, a methodological.
	CHAIRMAN BARTON.  Thank you, Mr. Chairman.
	MR. WHITFIELD.  Mr. Inslee, you are recognized for 
	10 minutes.
	MR. INSLEE.  Thank you.  I wanted to ask Mr. Karl about the
	conclusions, if I can find them here.  In your testimony you 
	talked about reviewing a variety of papers and you said of
	all the analysis, only one shows temperatures during medieval 
	times higher than those of the early 20th Century and none of 
	the analyses show temperatures higher than the last few 
	decades of the 20th Century and into the 21st Century.  So I 
	take it that means that none of the analyses that have been 
	done have shown temperatures at any point higher than the 
	last few decades and into this century. Is that an exhaustive 
	review of the analyses or is there something you might have 
	missed or is that pretty much a total review of the 
	literature on this?
	DR. KARL.  There is always a danger one could have missed a 
	report but none of the reports I looked at, which probably 
	seven or eight reports using the approaches from as been 
	discussed here.  I think "bonehead" is a term and RPG and 
	various terms have been given to these things, but I don't 
	think any of them show temperatures, except for one, that 
	were as warm as what we saw in the mid part of the 20th 
	Century, none of them as warm as the late part of the 20th
	Century and the early part of the 21st century, and in 
	addition, I might add the error bars are frequently being 
	discussed.  If you look at the error bars, the wide error 
	bars, the 95 percent confidence error bars, it is even hard 
	to find in those error bars in those reports to come up to 
	the levels as high as we see in the last couple decades.
	MR. INSLEE.  So is it a fair synopsis here that today we 
	have heard some criticism of one report that suggested that 
	these are higher temperatures we are experiencing now than 
	we have at any time in the last 1,000 years and multiple 
	reports that have reached the conclusion that it is likely 
	we are having higher temperatures right now than we did at
	any time in the last 1,000 years.  Is that sort of a fair 
	statement of what we are hearing?
	DR. KARL.  I think so, and again, the word "likely" you 
	know, I point out, we use the word "likely" with better 
	than two to one odds and so with that kind of a caveat, I 
	feel quite comfortable in saying that.
	MR. INSLEE.  Well, the way I look at this, just so you
	know, is that you have got about six studies showing that
	gravity exists and you have got one study questioning the 
	statistical mechanisms used in one of those six studies, 
	and I sort of conclude that both gravity and global 
	warming due to human activity exist, and that is just how 
	I look at it.  I want to refer--you also concluded, 
	"These analyses indicated that the later half of the 20th
	Century is certainly warmer than any time during the past
	several hundred years, parentheses, based on the length of
	the borehole and glacial length proxies, paren, and the
	past 1,200 years based on isotopic ice core records."  So 
	you indicated that these are warmer during the past 
	several years and you say based on the length of the 
	borehole and glacial length proxies.  What are those two 
	proxies?
	DR. KARL.  Those are proxies that are completely independent
	of the tree ring analysis which is heavily used in some of 
	these multi-proxy reconstructions.  But the borehole 
	measurements are--there is probably about--I think the 
	academy actually gave a number of about 679 different 
	boreholes where the conduction of heat from the atmosphere 
	is constantly conducting into the Earth's surface and you 
	can go back in time to try and deduce what the actual 
	temperatures were in the lower parts of the atmosphere.  Now, 
	you have to be careful which boreholes you look at but 
	nonetheless, with current methods, you can go back to about 
	400 or more years.  That was an important piece of evidence 
	that when we did the IPCC in 2001 we intercompared those 
	borehole measurements with the Mann record, for example.
	MR. INSLEE.  So as I take it then, we have got totally 
	independent results independent from the Mann analysis that
	is consistent with the conclusion that it is likely that we
	are in warmer temperatures now than we have been in the 
	last several hundred years.  Now, you made reference to
	glacial length proxies.  What are those?
	DR. KARL.  Now, the glacial length proxies, this is where a 
	model was used to try and look at the ablation of glaciers 
	across primarily the Northern Hemisphere and a model has 
	been shown to be able to reproduce approximately the 
	temperatures that would be needed to cause those glaciers to
	melt.  Again, you have to be careful about what glaciers you 
	select.  Some of them are more sensitive to precipitation but 
	nonetheless another independent method, and again, it shows 
	that the later part of the 20th Century is warmer than 
	anything we have seen in the last several hundred years.
	MR. INSLEE.  Now, you also reported that these analyses 
	indicated that these temperatures we are now experiencing are 
	warmer than in the past 1,200 years based on isotopic core 
	records.  Are the isotopic core records independent of the 
	Mann research and could you describe what they are?
	DR. KARL.  Yes.  They are independent as well.  The difference 
	is, they are far fewer in terms of geographic coverage.  So 
	what you are actually looking at here is the isotopic decay 
	within these records, the same kind of records that are looked 
	at for the air bubbles that are trapped in the ice.  Now you 
	try to relate through isotopic decay to temperatures and there 
	are some relationships that have been developed and again you 
	see some significant warming in the latter part of the 20th 
	Century compared to what we saw earlier.
	MR. INSLEE.  So we have multiple independent scientifically 
	sound measures to conclude these are the likeliest warmest
	temperatures we have had in 1,000 years independent of the 
	Mann report.  Is that correct?
	DR. KARL.  That is correct.
	MR. INSLEE.  Dr. Crowley, you talked about something that I 
	had heard and I appreciate you talking about it, about 
	amplitude, about the effect of how much amplitude there is in 
	the system, how sensitive the system it is to CO2 forcing, and 
	I think this is interesting because basically the Wall Street 
	Journal editorial staff has done everything they can to suggest 
	this is not a problem and they have attacked the Mann research 
	effectively saying that, but is it fair to say that actually if
	one would want to debunk the idea of global warming, if one 
	would want to say we shouldn't worry about global warming, if 
	one would want to say that we should really just continue on 
	our path of putting megatons of CO2 in the air without change, 
	if one really wanted to argue that, one would really want to 
	argue that Mann was right because Mann had a conclusion that 
	there was less effect on temperature by CO2 changes than some 
	of the other studies.  Is that right?
	DR. CROWLEY.  That is true.  Another way of putting it is that 
	those who love to hate Mann should learn to hate to love him.
	MR. INSLEE.  Well, that will take us about 8 minutes to figure 
	out up here on this panel.  But could you explain why that is?  
	I just heard this yesterday for the first time.  It is an 
	intriguing thought, that this could be a reversal of approaches 
	here, but why is it important to know how much CO2 can affect 
	temperature and what does the Mann research indicate versus 
	other research?
	DR. CROWLEY.  Well, it is like pushing on a string.  Jerry 
	North explained this to me years ago.  Suppose you have two 
	strings, one that is very thick, coiled spring, and then 
	another one that is very thin and weak.  You push on the thick 
	coiled spring, it is not going to move very much whereas one 
	that is very flexible is going to move a lot, and that is 
	really like pushing is like the climate forcing the responses 
	to climate system, so if you have a system that has a very
	low sensitivity, it is not going to respond much, like the 
	thickly coiled spring.  You have one that is less thickly 
	coiled, it is going to respond more and you are going to get 
	bigger temperature changes and that is the thing we worry 
	about, is whether the temperature change is being large, and 
	the study came out recently in Nature where we tried to 
	quantify that and that at least with respect to the 
	paleoclimate records and showed objectively what I was saying--
	MR. INSLEE.  So if Mann was wrong, this problem that we are 
	going to be at in 2100 when CO2 levels are twice the rate of 
	pre-industrial times--
	DR. CROWLEY.  We are going to have larger temperature 
	variability.
	MR. INSLEE.  So if Mann is wrong, that means we are going to 
	have greater increases in temperature once this CO2 levels 
	skyrocket like this and even some of the other researchers 
	have predicted.  Is that the situation?
	DR. CROWLEY.  Right.
	MR. INSLEE.  That will news to the Wall Street Journal 
	editorial board.
	DR. CROWLEY.  Sure.
	MR. INSLEE.  Thank you.
	MR. WHITFIELD.  Thank you, Mr. Inslee.  Dr. von Storch, in your 
	presentation you made the comment that parts of climate change 
	science, in particular paleoclimatic reconstructions have 
	suffered from gatekeeping and incestuous usage of reviewers and 
	then you talked about they have a bias toward interesting 
	results, and we have a lot of testimony today about the Wall 
	Street Journal and the oil industry and the coal industry love 
	to debunk all of this science about global warming, which may 
	be true, but I was interestingly reading an article the other 
	day about a gentleman named Chris Landsea, who was on the IPCC 
	panel and was an expert in hurricanes.  And we heard testimony 
	today in some of the opening statements that global warming is 
	causing more hurricanes, stronger hurricanes and it is a 
	serious problem.  Henry Waxman is the one that made that comment 
	and there was another person that made that comment.  And 
	Chris Landsea was asked by a gentleman named Dr. Kevin Trenberth 
	to provide the write-up for the AR4 assessment, the fourth 
	assessment report of the IPCC.  He was asked to do the write-up 
	for the Atlantic Hurricanes, and soon after he was asked, 
	Dr. Trinberth went to Harvard University and participated in a 
	program entitled on the topic: "experts to warn global warming 
	likely to continue spurring more outbreaks and intense hurricane
	activity."  And there was big press about it and there were all 
	sorts of articles written about it.  And Landsea was so upset 
	about this as they were just getting ready to do this assessment 
	that he submitted his resignation.  And he said, "It is beyond 
	me why my colleagues would utilize the media to push an 
	unsupported agenda that recenty hurricane activity has been 
	due to global warming.  Given Dr. Trenberth's role as the 
	IPCC's lead author responsible for preparing the text on 
	hurricanes, his public statements are so far outside of any 
	scientific understanding led me to concern that it would be 
	very difficult for the IPCC process to proceed objectively 
	with regards to the assessment on hurricane activity."  Now, 
	we are all human beings, we make a lot of mistakes.  We are 
	biased.  We do this, we do that.  But is that something that 
	happens in the IPCC frequently or infrequently or do you have 
	any comment about it?
	DR. VON STORCH.  Only through the media, and I had the 
	impression that this was not very helpful, what has happened 
	there, but I don't know the details, and this would be an 
	example where I would ask some social scientists to really go 
	after this, what really has happened here.  I think it would 
	be worth doing it.  But when we speak about this storm 
	business, I would like to tell a little story, namely in the
	early 1990s we had the press in northern Europe full of 
	messages that we would have more storms, and these storms 
	would be proof or would be a result of global warming going
	on.  And you have to know that when people think about 
	climate change, anthropogenic climate change in the past, it 
	always is associated with more storms.  So if you read about 
	the cooling in the 1970s, what the response would be, it was 
	cooler and more stormy, so it seems that it is part of our 
	cultural heritage that whenever we think we change climate 
	to the worse, then we have more storms.  Later on it turned
	out that we actually have less storms now in northern 
	Europe.  And if we believe our climate change models, and I 
	do believe them and I am sincerely convinced that we see 
	global warming happening.  If we believe these models then 
	we should have an intensification of storms in our part of 
	the world with stronger wind speeds of the order of 10 percent
	of the end of the century, that would be a signal which cannot 
	be detected.  While if you go into the details, then you find 
	out that several aspects are rather similar to the ongoing 
	hurricane debate, namely that good data exists only for a 
	short time.  Satellites are flying only since the 1970s or
	so, and observing this, and you have decades with strong 
	activity and decades with less strong activity.  It is the 
	same with the storms in our part of the world.  And so I 
	would say in this case one should be very careful in making 
	definite conclusions about that.  And if we believe our 
	models, and I am not sure if we should believe in this 
	respect our models, then we also should have a signal which 
	is much weaker now, hardly detectable at this time.  So in
	this case with the hurricanes, I would advise to wait a 
	little bit before definite conclusions are drawn.  And this 
	would be an example that somehow this preconception that
	storms are getting worse when climate is changing is somehow
	controlling what we think.
	MR. WHITFIELD.  Mr. McIntyre, I know that you and 
	Mr. McKitrick were the ones that first started looking at
	the Mann study or report.  How did that come about?  Was 
	this just an area of interest that you have had, or what?
	MR. MCINTYRE.  Well, that is actually a fairly long story
	but I was just--at that time I was just a private citizen. 
	The study was being--we were told in Canada that 1998 was
	the warmest year of the millennium.  I have worked in the
	mineral exploration business for many years.  I deal with 
	geologists who were unimpressed by that statement and I 
	just wondered one day how they knew that.  When I looked 
	at the IPCC report as somebody that is in the mineral 
	exploration business, which is a very promotional business, 
	I was struck at how promotional many of the statements 
	were and particular how promotional the hockey stick graph
	was.  I thought actually sort of in a professional way, 
	I thought it was well designed, well presented.  It was 
	there to convey a message but I certainly felt like I was 
	being sold when I saw that.  Some months later, business 
	was slow.  I thought I would be interested in looking at 
	the data.  I assumed there was some kind of due diligence
	package like you would see in a business thing that they 
	had prepared for the IPCC auditors.  At that time I had no
	idea that such things didn't typically exist in the 
	academic community so I e-mailed Dr. Mann out of the blue
	and asked him where the data was and just for the location
	of the data of this which I assumed to be part of the due 
	diligence package and he said he had forgotten where the
	data was.  So I was astonished as there had been so much
	publicity.  He said he would have an associate locate it 
	for me.  The associate said that it wasn't in any one 
	place, but he would get it together for me so I thought that
	was nice of him but just, it seemed an odd situation and I
	just thought well, nobody has ever looked at this and if
	nobody has ever looked at it, well, I will do it, so I didn't
	expect to be the center of an academic debate or any furor, 
	but when I looked at it, I started finding problems and here
	we are today.
	MR. WHITFIELD.  And I would ask Dr. Crowley and Mr. McIntyre
	or anybody else that wants to comment: the Wall Street 
	Journal that has been referred to many times today says that 
	Dr. Mann's methodology could produce hockey sticks from 
	random trendless data.  Is that a correct statement or is 
	that incorrect statement?
	MR. MCINTYRE.  Well, let me answer that.  That is true, and 
	that is the one specific item that was verified by both 
	panels, and both the NAS panel and the Wegman report 
	specifically confirm that his methodology would produce a
	hockey stick from random data.
	MR. WHITFIELD.  Okay.  Dr. Crowley, did you want to comment 
	on that?
	DR. CROWLEY.  I am not an expert in statistics so I just 
	have to defer from that answer.  All I can say is that when 
	we took a completely different approach with the very simple
	averaging, we got an answer that was pretty similar.
	MR. WHITFIELD.  Dr. von Storch?
	DR. VON STORCH.  I think I have a bit of reputation in 
	studies of climatology as I am the coauthor of I would say 
	the leading statistics book in that field.  So first of all,
	what Mr. McIntyre is saying is correct.  You can get that. 
	But this requires that you have no other significant signals 
	in the field, in particular no correlation in space, and
	this is not the case in climatological variables and so I 
	would say even if it is entirely true what he said and I 
	would include it in the next version of this book we have 
	written.  I would say in very many practical situations it 
	would not show up.
	MR. WHITFIELD.  Thank you.  My time has expired.
	CHAIRMAN BARTON.  Has Mr. Stupak not gone yet?
	MR. STUPAK.  No.
	CHAIRMAN BARTON.  Well, then let us get Mr. Stupak.  He has
	waited patiently all afternoon.
	MR. STUPAK.  Dr. Karl, if I may, Dr. von Storch says that 
	the reputation of the IPCC has increased to very high levels
	in the past years, that most lead authors are honest brokers
	of the work they review and that perhaps in such a complex 
	and large field as the IPCC is addressing, it may not be 
	possible to have lead authors who have not contributed to 
	the field.  But then Dr. von Storch concludes that an 
	independent review by the IPCC is not possible under the 
	current system.  How would you respond to that?
	DR. KARL.  Again, no human-conceived system is perfect.  I
	don't know how you might improve it in terms of the way it 
	operates today.  The peer review process really is driven by 
	others' availability to comment and the IPCC documents are
	open for everyone from every discipline to comment on 
	including the governments of the world.  I think one of the 
	issues that has been discussed in the hearing today is one 
	that is typical of science where you can publish something 
	but sometimes it takes a period of years to try and come up
	with a different analysis, technique, or to explore the 
	decisions that are made in a particular analysis technique. 
	The IPCC process right now is over a period of 2 years.  I 
	don't see how you could actually open up a process more 
	and I don't see how you could actually have a process 
	whereby every piece of information is going to be evaluated
	in terms of a new analysis, and that is the reason it is 
	done every 5 or 6 years to update, see if there are 
	differences.  So, for example, I am sure all the work being 
	done since the 2001 IPCC assessment and the next one that is 
	coming out next year will be included and assessed.
	MR. STUPAK.  Well, the 2001 IPCC report really referenced
	other studies other than the 1998 and 1999 Mann hockey stick 
	study, right?
	DR. KARL.  Yes.  In fact, as I said, it would have been--I 
	hate to use the words "very unlikely" because those are 
	like the words that are used in the IPCC but I don't think
	IPCC would have actually made a statement about the 1990s
	had it only been based on one article.  If it was just the
	Mann work, I just don't think we would have had the 
	confidence to say anything.
	MR. STUPAK.  I am looking at your 2001 report here, and I 
	am on page--and in there it says new analysis of proxy 
	data for the Northern Hemisphere indicate that the increase 
	in temperature in the 20th Century is likely to have been
	the largest of any century during the past 1,000 years.  It 
	is also likely that in the Northern Hemisphere the 1990s 
	was the warmest decade and 1998 was the warmest year.  That 
	was the conclusion of 2001 and that is based upon more than 
	just the Mann study.  Isn't that correct?
	DR. KARL.  That is correct.
	MR. STUPAK.  Okay.  You used the word "likely."  I know 
	today especially when the Chairman asked questions it was 
	like absolute based upon the Mann study and that is not the 
	case, it based upon--your 2001 report takes some other 
	things other than the Mann hockey stick study, right?
	DR. KARL.  That is correct.
	MR. STUPAK.  What is the significance of the word "likely"?  
	Not working in your field, I may have a different view of
	"likely" but you use it twice.  Can you give any further
	explanation of that?
	DR. KARL.  What we tried to do is clarify what we meant by
	the word "likely" because it can be taken all different 
	ways because it is used frequently in the literature.  We 
	define "likely" as a probability of the statement being 
	true between 66 and 90 percent of the time.  That means 
	slightly better than two to one odds at the low end, and 
	at the high end close to nine to one odds.
	MR. STUPAK.  You have been here all day.  Is there anything
	you have heard today which would make you change your mind
	about the conclusions of the 2001 IPCC report?
	DR. KARL.  No.  If you ask me to give qualifications about
	the findings in the 2001 report with the same caveat in 
	terms of defining likelihood, I personally would not
	change anything.
	MR. STUPAK.  And going further in this, your 2001 report,
	the IPCC report, they talk about the Jones et al., about 
	having the warmest year of the past millennium in the 
	Northern Hemisphere, Jones et al. in 1998 came to a 
	similar conclusion from largely independent data and 
	entirely independent methodology.  Crowley and Lowery in 
	2000 reach a similar conclusion.  Borehole data, Pollick, 
	et cetera, in 1998 independently support this conclusion 
	for the past 500 years.  So there is plenty of other 
	things to base that conclusion upon and not just the 
	Mann--
	DR. KARL.  That is correct.
	MR. STUPAK.  And somewhere today someone said something
	like there is over 900 reports or studies on global 
	warming.  Is that correct?
	DR. KARL.  I am sure there is even more than that.  I 
	think that was a random sample, so there is probably in 
	the tens of thousands.
	MR. STUPAK.  Okay.  Thank you.  Dr. Crowley, if I may, 
	when I was asking Dr. Wegman about this chart here, 
	which was showing the warm age there in around 1300 or 
	so, I think he called it the cartoon graph, was his word. 
	Is that based on any set of data or anything or--
	DR. CROWLEY.  That is pretty much a cartoon graph 
	ctually.  This is really in the first round of IPCC. 
	Nobody ever felt there was a need to--had thought of 
	whether there should be a need to have a quantitative 
	estimate of climate for the last 1,000 years.  They 
	wanted to try to provide a perspective and they didn't
	realize they didn't have one and they basically talked
	to some people and there was a lot of anecdotal 
	evidence for medieval warm period, that people said it
	was warmer than the present roughly during these years,
	you know, so it was really pretty much of a guesstimate, 
	and it was only when we started looking at a number of 
	sites that had a very good chronology so we knew where 
	they were in time and that we realized that the timing of 
	the warmth was not the same in different regions, that 
	that peak collapsed.
	MR. STUPAK.  So it is not fair to compare this cartoon 
	graph with Dr. Mann's hockey stick?
	DR. CROWLEY.  No, I don't think that was intention of 
	Dr. Wegman.  I think he was just--
	MR. STUPAK.  No, I guess the Wall Street Journal used 
	it more as one of those.  You said the Wegman report
	should not be a legitimate assessment of the science of 
	global warming or as a guide to policy modification.  
	Can you elaborate a little bit on that?
	DR. CROWLEY.  Well, I felt that--again, I have to--I 
	can't remember exactly where--do you have it listed where 
	I said that so I can--
	MR. STUPAK.  Let me find it here.
	DR. CROWLEY.  Last page.  So what I said is I disagree 
	with many in the fact sheet and also in the report itself. 
	It is not like I disagreed with what he was saying about
	his analysis of the Mann et al. record there but some of
	the recommendations that he was making I think that I
	felt there was a need---I just disagreed with him and so
	I was concerned that in terms of recommending any changes.
	I am not saying that interaction with statisticians is bad. 
	I strongly favor very enhanced interaction but a lot of 
	that is already happening.
	MR. STUPAK.  Mr. McIntyre, you are not a 
	paleoclimatologist, right?
	MR. MCINTYRE.  No.
	MR. STUPAK.  And you are not a statistician?
	MR. MCINTYRE.  I studied mathematics and statistics at 
	university.
	MR. STUPAK.  So are you a statistician then?
	MR. MCINTYRE.  I have not practiced as a statistician, but
	this is what I have been doing for the last few years.  I 
	think that--
	MR. STUPAK.  You have been doing statistics the last 
	2 years then?
	MR. MCINTYRE.  I have been working at statistical analysis
	of multi-proxy studies for the last 3 years.
	MR. STUPAK.  Three years.  Okay.
	MR. MCINTYRE.  I note that my findings have been endorsed 
	by both the NAS panel and the Wegman report.
	MR. STUPAK.  In this--again, reading the Wall Street Journal
	editorial.  I am not sure how accurate this is but it say 
	you and Mr. McKitrick published an article in a peer review 
	journal.  What discipline did the peer review?
	MR. MCINTYRE.  We have published articles in two journals, 
	Geophysical Research Letters, which is the same journal 
	that published the original Mann article, and Energy and
	Environment.
	MR. STUPAK.  Let me ask Dr. Crowley if I can.  Both you 
	and Dr. Karl and the National Research Council have stated 
	that the Mann study was not the most influential work in
	the IPCC 2001 report.  You testified that the papers that
	made the biggest differences were ones that said the 
	influence of greenhouse gases had to be used to reconcile 
	the data and the models and the most compelling driver was
	the fact that global temperatures kept going up and glacier 
	melt was increasing.  Why then is there so much emphasis on
	the Mann report?
	DR. CROWLEY.  Well, there has been this discussion before
	about it being used as an icon, okay, and people say well, 
	if it is not right, then is IPCC wrong, so there has then
	been that connection drawn.  So I think for rightly or 
	wrongly, I am not sure if IPCC is the only one responsible 
	for broad--for using that as an icon but it has effectively 
	become one and I think that is really the--what the--I 
	guess the argument settles down to.
	MR. STUPAK.  Thank you.  I guess my time is up.  We have 
	got 3 minutes to go vote.
	MR. WHITFIELD.  I want to thank all of you on the panel, 
	one, for being here, two, for being so patient, and three,
	for what you do and the contributions that all of you are 
	making.  We may or may not have some more hearings on this.
	I know we do have an invitation out to Dr. Mann and we
	will see if he is going to come or not.  But I want to 
	ask unanimous consent that the document binder be submitted
	into the record of this hearing, unanimous consent that the 
	document in Newsweek that Chairman Barton referred to about
	the cooling world be entered into the record and then I
	would like to keep the record open for 30 days for any 
	follow-up questions we may have.  So without objection, so 
	ordered and this hearing is concluded, and thank you all 
	again for being with us.  We genuinely appreciate it.
	[The information follows:]




	[Whereupon, at 4:12 p.m., the subcommittee was adjourned.]

RESPONSE FOR THE RECORD OF DR. GERALD R. NORTH, DEPARTMENT OF 
ATMOSPHERIC SCIENCES, TEXAS A&M UNIVERSITY


The Honorable Ed Whitfield

1. As you chaired the National Research Council panel that 
recently issued the report on millennial temperature 
reconstructions:
a. Where in the report did the panel describe "plausible" as 
suggesting roughly a 2/3rds probability of being correct?

In the report we shunned the use of numerical probability 
assessments in favor of descriptive statements (e.g., "high 
confidence") and statements that describe our relative confidence 
in different conclusions (e.g. "less confidence").  I may have 
mistakenly mentioned the "two to one odds" figure in the oral 
press release of the report, and it may also have appeared in 
some press accounts, but it does not appear in the report, and 
I avoided using it in my sworn testimony.  

b. In the report, did the panel attach probability estimates to
the term "plausible"?  

No. The committee avoided numerical probability estimates because 
many of the uncertainties associated with reconstructing surface
temperatures are not purely statistical in nature, but rather 
arise from physical factors associated with each proxy that 
are simply unquantifiable at this time.  In our view it is not
possible to quantify all of the inherent uncertainties 
associated with reconstructing surface temperatures from proxy 
data, which in turn precludes assigning numerical probabilities 
to statements regarding the unique nature of recent warmth.

c. Why did the panel choose to use the term "plausible," as 
opposed for example to terms such as "likely," to describe
confidence in millennial temperature reconstructions? 

In the IPCC reports, the term "likely" is used to indicate an
estimated probability of between 66% and 90%, i.e. greater 
than two-thirds odds but less than nine-in-ten chances.  We 
avoided numerical estimates such as these because we did not
want to imply that we had performed a rigorous probability 
assessment.  Instead, we tried to express our collective 
confidence in different conclusions using descriptive 
language.


2. When considering the panel's findings that it is "plausible" 
that recent decades were the warmest in a millennium, is that 
correct to interpret that to mean the panel's consensus view 
was that plausible means roughly a 2/3rds probability of being
correct, as was suggested in news reports following the press 
conference releasing the report?

Our working definition of "plausible" was that the assertion 
is reasonable, or in other words there is not a convincing 
argument to refute the assertion. We used this term to describe 
our assessment of the statement that "the last few decades of 
the 20th century were warmer than any comparable period over 
the last millennium" because none of the available evidence to
date contradicts this assertion. In our view it is not 
currently possible to perform a quantitative evaluation of
recent warmth relative to the past 1,000 years that includes 
all of the inherent uncertainties associated with reconstructing 
surface temperatures from proxy data.  This precludes stronger 
statements of confidence, but it does not mean that the 
assertion is false.  In fact, all of the large-scale surface 
temperature reconstructions that we examined support the 
assertion that global-mean temperatures during the last few
decades of the 20th century were unprecedented over at least 
the past 1,000 years, and a larger fraction of geographically
diverse proxy records experienced exceptional warmth during 
the late 20th century than during any other extended period 
from 900 A.D. onward.


3. Did the panel perform its own, in-depth technical analysis 
of the methods and procedures-- such as checking the underlying
data sets or attempting to replicate the findings - used in the 
various temperature reconstruction articles and presentations 
it considered in formulating its report?

Our committee relied on the published, refereed scientific 
literature to reach its conclusions.  We did not attempt to 
replicate the work of any previous author, with the lone 
exception of a simple computer program (reproduced in Appendix B 
of our report) that was used to illustrate an interesting 
artifact of the principal components methodology first noted by 
McIntyre and McKitrick.  When evaluating the results of different
studies, we placed higher confidence in those results that were 
reproduced in several different studies--for instance a number 
of independent lines of evidence indicate that the late 20th
century warmth was unprecedented in at least the last 400 years,
giving us high confidence in this conclusion.  Less confidence 
can be placed in conclusions regarding large-scale surface 
temperatures prior to about 1600 A.D. because there are simply
fewer independent lines of evidence to consider, although the 
evidence that does exist indicates that the late 20th century 
warmth is unprecedented for at least the last 1,000 years.


4. The NRC panel made specific reference to ice borehole studies 
in Greenland by Dahl-Jensen, which suggest warmer temperatures 
in that region during the Medieval Warm Period than today. Please
explain the value of regional temperature measurements such as
this for understanding the potential effects of recent warming 
trends?

There are two main reasons for using large-scale averages rather 
than individual regional measurements to evaluate global 
environmental changes: 1) Random measurement errors and climate 
fluctuations tend to cancel out when spatial averages are 
performed, allowing researchers to obtain a more reliable 
estimate than is possible for a local or a regional average; 
2) The greenhouse effect operates at the global scale, hence 
large-scale averages are the best way to evaluate the response
of the climate to increasing greenhouse gas concentrations. 
Current climate models also are better at computing large-scale
averages than regional-scale values.  

Of course in order to detect large-scale climate anomalies, 
either in the modern temperature record or in proxy-based 
temperature reconstructions, it helps to have a large network of
high quality measurements for geographically-diverse regions. 
The main reason that we have high confidence in the temperature 
increase over the past 100 years and in the statement that
temperatures are warmer now than at any other time over the last
400 years is because we have a sufficiently large number of 
well-characterized local measurements to calculate a reliable 
large-scale average.  Several proxies (including historical and 
archeological evidence as well as quantitative temperature 
estimates from ice cores and boreholes) indicate that the area 
around Greenland was warmer between about 1000 and 1200 A.D. 
than it is today.  There is also evidence for warm temperatures 
during medieval times from other regions of the world.  However, 
studies suggest that these warm anomalies appear to have occurred
at different times at different places rather than being globally
synchronous, and also appear to have been offset by cold 
anomalies in other regions.  The few large-scale surface 
temperature reconstructions that extend back far enough to 
rigorously compare large-scale medieval temperatures to modern 
warmth suggest that the medieval period was, at most, comparable
in warmth to the first half of the 20th century.  However, as 
noted above in response to question (4), it is difficult to 
quantify the full uncertainty associated with estimates of 
surface temperature prior to about 1600 A.D.  


The Honorable Bart Stupak

1. In the study performed by a special committee of the National
Academy of Sciences (NAS) on surface temperature reconstructions 
over the past 2,000 years, it was stated that, for the time prior 
to 1600 A.D., scientists are less certain about the actual 
average northern hemispheric surface temperatures. The Medieval 
Warm Period (MWP) occurred prior to 1600.  How certain are
climatologists that there was a globally or even hemispherically 
MWP that was warmer than the past several decades?

Indeed, the paucity of proxy data for periods prior to about 
1600 A.D., especially in the tropics and the Southern Hemisphere,
limits our confidence in statements regarding the global mean 
temperature of the past few decades compared to medieval times. 
Several proxies indicate that the area around Greenland was 
warmer between about 1000 and 1200 A.D. than it is today.  There 
is also evidence for warm temperatures during medieval times 
from other regions of the world.  However, studies suggest that
these warm anomalies appear to have occurred at different times 
at different places rather than being hemispherically or globally
synchronous, and also appear to have been offset by cold anomalies
in other regions.  Although it is difficult to quantify the full 
uncertainty associated with estimates of surface temperature prior
to about 1600 A.D., all of the large-scale surface temperature 
reconstructions that we examined support the assertion that 
global-mean temperatures during the last few decades of the 
20th century were unprecedented over at least the past 1,000 
years, and a larger fraction of geographically diverse proxy 
records experienced exceptional warmth during the late 20th 
century than during any other extended period from 900 A.D. 
onward.  Hence we find it plausible (or in other words, no 
evidence exists to refute the claim) that "the last few decades 
of the 20th century were warmer than any comparable period over
the last millennium."  This statement can be more strongly 
applied to the Northern Hemisphere than to the globe because 
there is very little proxy data from the Southern Hemisphere 
before about 1600 A.D.


2. The 1990 Intergovernmental Panel on Climate Change (IPCC) 
Report contains a "schematic diagram" that shows temperature
changes for 900 A.D. through 1975, but does not give specific
temperatures. The text of the report notes, "it is still not 
clear whether all the fluctuations indicated were truly global." 
Am I correct in my understanding that this schematic diagram is 
not a graph of specific data points consisting of global 
temperature for particular years or time periods? Am I also 
correct that the scientific consensus at the time was that 
there was significant uncertainty about whether the diagram 
accurately portrayed the global temperature profile over the 
last 1,000 years?

Yes, the schematic diagram that appeared in the 1990 IPCC 
Report was simply a qualitative depiction of how scientists 
thought that large-scale temperatures may have evolved from 
900 A.D. to about 1975. There was very little proxy data 
available at that time, and the data that did exist tended to 
be concentrated in just a few geographical regions, such as 
Greenland.  The lack of a temperature scale and supporting 
documentation strongly suggests that the diagram was not
based on a quantitative analysis, and also implies that 
there was considerable uncertainty about the magnitude and 
timing of the indicated fluctuations.  As stated in our 
report, there is still considerable uncertainty about the 
exact timing and magnitude of past temperature fluctuations,
especially prior to about 1600 A.D., but our knowledge has
advanced considerably since 1990.  Figure S-1 from our 
report illustrates the current state of the science in 
large-scale surface temperature reconstructions for the 
last 1,000 years.


3. What level of certainty is there that the temperature ranges 
for the period of 900 through 1975 A.D. schematically displayed
in the 1990 IPCC report are accurate? Prior to Dr. Mann's work, 
had anyone attempted to attach a level of certainty to the data 
relating to surface temperature reconstruction?

There were no uncertainty assessments attached to the 1990 IPCC 
diagram.  As discussed in response to question (2) above, this 
diagram was simply a qualitative depiction of how scientists 
thought that large-scale temperatures may have evolved from
900 A.D. to about 1975.  The papers by Dr. Mann and his 
colleagues in 1998 and 1999 were, to my knowledge, the first 
attempts to assign statistical error bars to a large-scale
surface temperature reconstruction. As noted in our report,
these error bars provide an indication of how well the
reconstructed temperatures match observations during the 
"calibration period," but they do not represent all of 
uncertainties inherent in reconstructing surface temperature 
from proxy data.  The actual uncertainties in the 
reconstruction would be somewhat larger, and difficult to
quantify.

4. Mr. McIntyre has testified that the NAS report stated that 
the bristlecone pine proxy used by Dr. Mann in his original 
work should not have been used. Was that the conclusion of the
panel? Please describe the conclusion and provide citations.

Let me quote directly from page 50 of the prepublication 
version of our report:

The possibility that increasing tree ring widths in modern 
times might be driven by increasing atmospheric carbon 
dioxide (CO2) concentrations, rather than increasing 
temperatures, was first proposed by LaMarche et al. (1984) for
bristlecone pines (Pinus longaeva) in the White Mountains of 
California. In old age, these trees can assume a "stripbark" 
form, characterized by a band of trunk that remains alive and
continues to grow after the rest of the stem has died. Such 
trees are sensitive to higher atmospheric CO2 concentrations 
(Graybill and Idso 1993), possibly because of greater water-use 
efficiency (Knapp et al. 2001, Bunn et al. 2003) or different 
carbon partitioning among tree parts (Tang et al. 1999). Support
for a direct CO2 influence on tree ring records extracted from 
"full-bark" trees is less conclusive. Increasing mean ring width 
was reported for Pinus cembra from the central Alps growing well 
below treeline (Nicolussi et al. 1995). Free-Air CO2 Enrichment 
(FACE) data for conifer plantations in the Duke Forest (Hamilton
et al. 2002) and at the alpine treeline (H�ttenschwiler et al. 
2002) also showed increased tree growth after exposure to 
atmospheric CO2 concentrations about 50 percent greater than 
present. On the other hand, no convincing evidence for such 
effect was found in conifer tree ring records from the Sierra 
Nevada in California (Graumlich 1991) or the Rocky Mountains in
Colorado (Kienast and Luxmoore 1988). Further evidence comes 
from a recent review of data for mature trees in four climatic 
zones, which concluded that pine growth at treeline is limited 
by factors other than carbon (K�rner 2003). While 'strip-bark' 
samples should be avoided for temperature reconstructions, 
attention should also be paid to the confounding effects of 
nthropogenic nitrogen deposition (Vitousek et al. 1997), since 
the nutrient conditions of the soil determine wood growth
response to increased atmospheric CO2 (Kostiainen et al. 2004). 
However, in forest areas below treeline where modern nitrogen
input could be expected to influence dendroclimatic records, 
such as Scotland (Hughes et al. 1984) and Maine (Conkey 1986),
the relationship between temperature and tree ring parameters
was stable over time.
 
In summary, it appears that there is a carbon dioxide 
fertilization effect in some trees, but not in all the places 
where the samples used in the Mann et al studies were taken.  
Also note that this section of the report discusses the 
calibration of tree-ring records since atmospheric carbon dioxide
levels started to increase around 150 years ago.  Hence, in 
context, what the clause "strip-bark samples should be avoided
for temperature reconstructions" was intended to convey is that
strip-bark samples from the mid-19th century to the present are
very difficult to calibrate against instrumental records of
temperature, and the easiest solution is therefore not to use 
them.  However, strip-bark data are considered suspect only after 
the modern increase in atmospheric carbon dioxide concentrations. 
This is why other studies that rely on strip-bark pine records 
only use them to infer past temperatures prior to 1850 (e.g.,
Biondi et al. 1999).  This reference, and all of those cited in
the above quote, can be found in the reference section of our 
report.


5. The recent work by Wahl & Amman redid Dr. Mann's original 
work, but recentered it as Mr. Mcintyre suggested. Wahl and 
Amman's work, however, resulted in the same "hockey stick" 
distribution. Please explain why this work was not fully 
considered and evaluated in the NAS study.

We did consider the Wahl and Ammann paper that was accepted for
publication in the journal Climatic Change on February 28th of 
this year, in which they found that decentering has only a 
relatively minor influence on the shape of the final 
reconstruction. This paper was one of many that influenced our 
evaluation of the Mann et al. (1998, 1999) papers and the 
robustness of surface temperature reconstructions in general.  
The effects of decentering are described explicitly in Chapter 
9 of our report, and our conclusions regarding how decentering 
influences surface temperature reconstructions can be found in
the following excerpt from page 106 of the prepublication 
version of the report:

As part of their statistical methods, Mann et al. used a type
of principal component analysis that tends to bias the shape of 
the reconstructions.  A description of this effect is given in 
Chapter 9.  In practice, this method, though not recommended, 
does not appear to unduly influence reconstructions of 
hemispheric mean temperature; reconstructions performed without 
using principal component analysis are qualitatively similar 
to the original curves presented by Mann et al. (Crowley and 
Lowry 2000, Huybers 2005, D'Arrigo et al. 2006, Hegerl et al.
2006, Wahl and Ammann in press).

Drs. Wahl and Ammann (along with Dr. Ritson) also authored a 
paper that appeared in Science magazine on April 28th of this 
year alongside a response written by Drs. von Storch and
Zorita.  These papers were under embargo during our
deliberations, and thus we were not able to consider them 
during our deliberations, although we did note (on page 105) 
that "the...debate in the scientific literature continues even
as this report goes to press (von Storch et al. 2006, Wahl et 
al. 2006)."  These papers address a separate statistical issue
than the one discussed above, in particular the issue of 
detrending the data prior to performing principal components 
analysis.  My personal impression of these two papers is that 
the quote cited above still applies, that is, none of the
statistical criticisms that have been raised by various authors
unduly influence the shape of the final reconstruction. This is
attested to by the fact that reconstructions performed without 
using principal components yield similar results.


6. In the hearing, Dr. Wegman challenged "anybody" to tell him 
the difference between 72 and 74 degrees Fahrenheit. Please 
describe the climatic and other changes that can result from a 
global increase in temperature of 2 degrees Fahrenheit.

As context, let me first point out that the difference in 
global-mean temperature between today and the height of the 
last Ice Age, when New York and Seattle were covered with over 
a kilometer of ice, is estimated to be only about 10 degrees
Fahrenheit.  Hence, a change in global-mean temperature of two
degrees would represent a considerable perturbation to the 
global climate system.  Small changes in local temperatures
can also be associated with large impacts. For example, for 
every degree Fahrenheit increase in mean annual temperature 
near Greenland, the rate of sea level rise is projected to 
increase by 10%. Snowpacks on mountains in the western U.S., 
which millions of people depend on for drinking water and 
other uses, is likewise extremely sensitive to small 
temperature changes.  Natural ecosystems are also vulnerable 
to changes in temperature--in the Midwest, a one degree 
change in annual mean temperature might translate into 
several hundred miles in the ecological distribution of 
certain plants and grasses, and a warming of just a few 
degrees could have devastating impacts on New England's maple 
syrup industry and California's vineyards. Many parts of 
the climate system are already feeling the impacts of the 
one degree rise in global-mean temperature observed during 
the 20th century. As we noted on page 27 of the prepublication
version of our report: "glaciers are retreating, permafrost 
is melting, snowcover is decreasing, Arctic sea ice is
thinning, rivers and lakes are melting earlier and freezing 
later, bird migration and nesting dates are changing, flowers 
are blooming earlier, and the ranges of many insect and plant
species are spreading to higher latitudes and higher elevations
(e.g., ACIA 2001, Parmesan and Yohe 2003, Root et al. 2003, 
Bertaux et al. 2004, Bradshaw and Holzapfel 2006)."


7. Dr. Von Storch testified that the effect of the "decentering"
error in the Mann study, which was the basis of the McIntyre and 
Wegman criticisms, was "very minor." The NAS study did not refer
to "decentering." How significant was the analysis of "decentering"
to the NAS conclusions?

I believe Dr. von Storch was referring to the same phenomenon that
I described in my response to your question #5.  Our committee 
did consider the effects of decentering, along with other 
criticisms of the Mann et al methodology, and found that it 
"does not appear to unduly influence reconstructions of 
hemispheric mean temperature."


8. At the hearing you were asked if you disputed the conclusions 
or the methodology of Dr. Wegman's report, and you stated that
you did not. Were you referring solely to Dr. Wegman's criticism
of the statistical approach of Dr. Mann, or were you also 
referring to Dr. Wegman's social network analysis and conclusions?

Dr. Wegman's criticisms of the statistical methodology in the 
papers by Mann et al were consistent with our findings.  Our 
committee did not consider any social network analyses and we 
did not have access to Dr. Wegman's report during our 
deliberations so we did not have an opportunity to discuss his 
conclusions.  Personally, I was not impressed by the social 
network analysis in the Wegman report, nor did I agree with most
of the report's conclusions on this subject. As I stated in my 
testimony, one might erroneously conclude, based on a social 
network analysis analogous to the one performed on Dr. Mann, that
a very active and charismatic scientist is somehow guilty of 
conspiring or being inside a closed community or 'mutual 
admiration society'.  I would expect that a social network 
analysis of Enrico Fermi or any of the other scientists 
involved with the development of modern physics would yield a
similar pattern of connections, yet there is no reason to
believe that theoretical physics has suffered from being a 
tight-knit community.  Moreover, as far as I can tell the only 
data that went into Dr. Wegman's analysis was a list of 
individuals that Dr. Mann has co-authored papers with.  It is
difficult to see how this data has any bearing on the 
peer-review process, the need to include statisticians on every
team that engages in climate research (which in my view is a
particularly unrealistic and unnecessary recommendation), or 
any of the other findings and recommendations in Dr. Wegman's 
report.  I was also somewhat taken aback by the tone of the
Wegman Report, which seems overly accusatory towards Dr. Mann
and his colleagues, rather than being a neutral, impartial
assessment of the techniques used in his research. In my 
opinion, while the techniques used in the original Mann et al
papers may have been slightly flawed, the work was the first 
of its kind and deserves considerable credit for moving the 
field of paleoclimate research forward. It is also important 
to note that the main conclusions of the Mann et al studies 
have been supported by subsequent research. Finally, while our
committee would agree with Dr. Wegman that access to research 
data could and should be improved, as discussed on page 23 of
the prepublication version of our report, we also acknowledge 
the complicated nature of such mandates, especially in areas 
such as computer code where intellectual property rights need 
to be considered.


The Honorable Marsha Blackburn

1. Dr. Mann used many temperature measurements from different 
sources to produce his graph. In your opinion, how much 
emphasis or reliance did he place on surface records and 
satellite measurements?

To perform their surface temperature reconstruction, Dr. Mann 
and his colleagues made use of proxy data derived primarily 
from tree rings, ice cores, and documentary sources.  Tree 
rings and ice cores, like other natural proxies, do not record 
temperature directly, but are correlated with local temperatures
through physical and physiological mechanisms.  They also 
made use of surface thermometer records from the last 150
years, which were used to calibrate the reconstruction (i.e. 
translate the proxy data into a record of temperature) and to 
validate their results (i.e. test whether the reconstructed 
temperatures match a portion of the observations reserved for
this purpose).  All paleoclimate reconstructions use a similar 
methodology, with the exception of reconstructions based on
borehole temperature measurements and glacier length records, 
which are translated directly into temperature time series 
using models based on the laws of physics. Satellite measurements 
are not used in any paleoclimate reconstructions because they 
only go back about 30 years, which is much too short for this 
application.

a. How much weight do you think should be given to these 
measurements?

Dr. Mann and his colleagues used all of the quality-controlled
proxy data that they had at their disposal at the time. As we 
indicated in our report, the available proxy data are plentiful 
and geographically diverse for the last 400 years, but decrease 
in number and become subject to increasing uncertainties going 
back further into the past. Hence, we have high confidence in
the surface temperature reconstructions based on these data for
the last 400 years, but less confidence in reconstructions for
the period from 900 to 1600 A.D.  This increasing uncertainty 
moving back in time is reflected, in part, by the increasing
size of the error bars prior to 1600 A.D. in the original 
'hockey stick' curve, although these error bars do not accoun
t for all of the uncertainties inherent in the reconstruction.


2. The surface record and the satellite measurements indicate
that if maybe natural warming and not human-induced warming. 
Yet, in your testimony, you say that increasing concentrations
of greenhouse gases caused the warming. How do we reconcile 
your statement with the historical record?

The temperature record alone cannot tell us the difference 
between 'natural' and 'human-induced' temperature changes. One 
has to try to explain the observed warming using the laws of
physics. During the last 100 years, the global-mean temperature
first increased strongly, then remained constant or decreased 
slightly, then increased strongly again.  Simple radiative 
transfer calculations and sophistical climate models both show
that the total amount of warming observed over the 20th 
century is consistent with the observed increases in greenhouse
gas concentrations in the atmosphere, which are undeniably the 
result of human activities. Changes in solar output can also 
influence the climate system.  However, satellite measurements 
show that the sun has not increased in luminosity over the 
last 30 years, and estimates based on terrestrial measurements 
show only a modest increase in solar output during the first
half of the 20th century.  A third factor that may have had a 
significant influence on global-mean climate during the 20th 
century is atmospheric aerosols. These are the tiny particles 
that, like greenhouse gases, are emitted from volcanoes and 
other natural sources as well as from anthropogenic sources, 
but have been increasing in concentration in the atmosphere over
the past century mainly due to the burning of fossil fuels and 
other human activities.  Aerosols influence climate in a variety 
of ways, some of which are well known and others of which are 
active areas of research, but in general they have a cooling 
influence on climate.  There is some evidence that suggests that
aerosols may be primarily responsible for the slight decrease in
global-mean temperature observed during the middle of the 20th 
century, and they might also be offsetting some of the warming 
due to greenhouse gases. 

a. Also, the historical record indicates that in the past 100 
years, the Earth's global temperature warmed and cooled 
significantly while the concentrations of carbon dioxide 
increased. Would this not also indicate that the level of carbon
dioxide in the atmosphere has had little effect on the warming 
of the atmosphere?

No. The Earth's temperature over the past 100 years was 
influenced by increases in carbon dioxide and other greenhouse 
gases, which have a warming effect, by changes in aerosols, which
generally cool the climate, and by other climate forcings.  
Thus, the observed temperature variations reflect the net effect
of these different forcings.  

We have a very good understanding of the direct impact of carbon 
dioxide and other greenhouse gases on global temperature.
Straightforward radiative transfer calculations tell us that
carbon dioxide has a significant influence on global climate.  
Sophisticated climate models also show that the observed 
temperature changes during the 20th century cannot be reproduced 
unless greenhouse gases increases are included. There are also 
other lines of evidence indicating that carbon dioxide and other
greenhouse gases have a strong influence on global climate.  For
example, models cannot reproduce the global-mean cooling that 
occurred during the last Ice Age without incorporating the reduced 
levels of greenhouse gases that prevailed during that time. 


3. You also state in your testimony that even if it was as warm 
or warmer 1000 years ago than today that it would not effect
today's consensus on global warming. That seems to not be logical
because if the Earth goes through natural cycles of warming and 
cooling, then would not the warming and cooling cycles over the 
past 60 and 500 years be a similar indication of phenomenon?

It is true that the Earth has experienced natural cycles of 
warming and cooling over its history, however natural climate 
forcings (solar activity, changes in natural aerosols) observed
over the last century are not large enough to produce the 
observed warming, especially for the last 30 years. There is a 
large and compelling body of evidence indicating that human-
induced greenhouse gas increases are responsible for at least
part of the total warming over the 20th century, and most of 
the warming over the last 30 years.  Over the last 100 years 
and especially the last 30 years, we have very good data for 
both temperature and all of the major climate forcings 
(greenhouse gases, solar activity, and aerosols).  Analyses of
these data indicate that human-induced greenhouse gases appear
to be responsible for much of the warming over the last 30 
years and at least part of the total warming over the last 
century. Reconstructions of surface temperature over the past 
1,000 years are one piece of the scientific evidence, but 
these reconstructions are sufficiently uncertain, especially 
prior to 1600 A.D., that they are not usually considered to be
among the primary evidence for human-induced global warming.  
In addition, temperature data alone do not tell us anything
about cause and effect.  

In contrast, we know that greenhouse gases did not vary much 
during the 1,000 years prior to the industrial revolution, 
but we have very little data about how solar output and 
aerosols varied over this period.  Moreover, what little 
evidence we do have shows only small variations in climate 
forcing due to natural causes. Hence, if we were to find 
out that the global-mean temperature 1,000 years ago was 
warmer than today, this would mean that the Earth's climate
is even more sensitive to small forcings than we thought, 
which would mean that projections of future warming may be 
overly conservative.


RESPONSE FOR THE  RECORD OF DR. THOMAS J. CROWLEY, NICHOLAS 
PROFESSOR OF EARTH SCIENCE SYSTEM, DUKE UNIVERSITY

Response by T. Crowley to Followup Questions on July 19 
Testimony

The Honorable Marsha Blackburn:

1. Do you agree or disagree with the surface record and 
satellite data which indicate that global temperatures did not
start to rise significantly until the 1998 El Nino?

I emphatically disagree with this statement.  The surface 
temperature record clearly shows very substantial warming 
before 1998.  Recent work furthermore indicates that the 
satellite observations are close to being reconciled with these 
surface observations - and that the prior differences between 
the two was to a coding error in the analysis of the satellite 
data, not a problem with the surface data.   Congresswoman 
Blackburn, anyone who tries to tell you that the warming did 
not occur until 1998 is seriously misleading you.  


2. Do you believe the available data shows a global Little 
Ice Age and/or Medieval Warm Period?  

It is not easy to give an unequivocal answer to this, because
southern hemisphere data are considerably more spotty than 
northern hemisphere data.  The available data suggest that 
the southern hemisphere did indeed have a cold period about
the same time as the northern hemisphere.  There are some 
indications of warmth in the southern hemisphere prior to 
that time, but it is not clear whether the timing of that 
warmth was the same as in the northern hemisphere. Although
some northern hemisphere places during the Middle Ages were 
locally warmer than they are today, in the best-dated records
the timing of Medieval warmth varied in different places.  
This is why composite reconstructions almost always show that 
the mean warmth for the Middle Ages is usually comparable to 
the mid-20th century but not the late 20th century.


3.  Do you agree or disagree with the statement that warming 
from  1900 to 1940 was caused by increase of solar activity 
or the warming of the Sun?

I disagree with the statement because it is too categorical. 
There are some indications that changes in solar behavior may
have contributed to the mid-20th century warming.  But when 
this "solar connection"is tested by going farther back in time 
the conclusions become much more equivocal.  The most methodical 
analysis (see Attachment #1 - Hegerl et al. 2003) provides at
best weak support for the long-term role of solar variability. 
Furthermore, the magnitude of past solar variations is very 
uncertain - even optimistic estimates indicate it is only a 
fraction of present greenhouse gas forcing.   The present 
thinking is that the mid-20th century warming was due to a 
combination of weakened volcanic cooling, greenhouse warming, 
"natural variability", and perhaps a modest contribution from 
solar output changes.


4.  What is your opinion on the effect of the 1998 El Nino on 
the recent rise in temperatures?  

The 1998 El Nino certainly contributed to the (at that time) 
record global temperatures but I don't think anyone seriously 
thinks it has a long term effect on global temperature - the
heat just dissipates too quickly in the atmosphere to have 
such an effect.  I might add that it has taken less than a 
decade for the continually rising temperatures to approach or
equal the 1998 temperatures.  This increase is very 
disconcerting in terms of how fast the planet is warming.

End of reply to the Honorable Marsha Blackburn

 
The Honorable Bart Stupak:

1. In the hearing, Dr. Wegman testified that your 2000 published 
work, which used a simple averaging proxy methodology, obtained 
the same "hockey stick" configuration as Dr. Mann's original 
work did.  Dr. Wegman blames this conclusion on "proxies 
appropriately selected" apparently because of use of the 
bristlecone pine proxy.

Please explain if and why your work also used the bristlecone 
pine proxy and respond to Dr. Wegman's criticisms of its use.

I do not recall Dr. Wegman making this testimony but will a
ccept your claim.  Actually the purpose of the Crowley-Lowery
2000 study (ms. submitted as hard copy during testimony) was 
not to reproduce Mann et al. with a different methodology but 
just to determine what would happen if we took a broad swath 
of data and just summed them up.  I was as surprised as anyone
that the result was as close to Mann et al. as it was - bristlecone 
pine or no bristlecone pine (the one we used was different than 
Mann et al's).  The principal significance of our finding was that 
the Mann et al. result appeared to be robust because it could be 
reproduced with a different methodology - a standard approach in 
science.  

The bristlecone pine business is a red herring.  If the bristlecone 
pine record is removed from the composite of a dozen or so records, 
it will show slightly greater warming in the Middle Ages.  But one 
record can only make so much a difference when it is averaged among
a dozen, especially since the general shape of the bristlecone pine 
record is comparable to the other records.

A more important objection to the bristlecone pine argument is that 
it should not be included.  Why not?  In statistics anyone can use 
something as a predictor or something else.  The question is how 
could a predictor is it?  Some have claimed that it should not be 
included because it is more affected by some other process (for
example, precipitation).  But a principal assumption of regression 
based prediction approaches is that the variables used for making 
predictions are linearly correlated with the variable they are 
predicting (in this theoretical case, precipitation with temperature). 
The degree of skill in the predictor can be tested by its correlation 
with temperature.  If it has a poor correlation, it has little skill. 
This is an approach we have adopted in later papers, but the purpose 
of the original study was to just take as simple as an approach as
possible.



2. There were numerous references in the hearing to a schematic 
drawing of what scientists supposed surface temperatures might have 
been from 1000 A.D. to 1975 in the 1990 report of the
Intergovernmental Panel for Climate Change (IPCC) .  You stated in 
your testimony that Dr. Mann's study represented the first attempt 
to estimate the uncertainties for surface temperature reconstructions
prior to the instrumental period.  Can you describe what level of 
uncertainty would have been placed on the 1990 schematic drawing, 
and what level of uncertainty Dr. Mann established for the period 
prior to 1600 A.D.  

This is a good question!  But before answering it I have to explain 
what happened during the formulation of the 1990 figure.   At that 
time we really did not have any hemispheric estimates of temperature.  
What IPCC did in 1990 was informally poll various experts for a  
"guesstimate" of what the temperatures were like (I vaguely recall 
being asked by someone around that time, but I do not know if it was
related to the IPCC figure).  Many scientists had heard of the 
"Medieval Warm Period" and stories of warmth greater than the 
present.  Despite warnings from a prominent Chinese scientist, and 
a prominent English scientist, that the timing of warmth in the 
Middle Ages was not the same in all places, many people (including 
some still now) assumed that the Medieval Warmth was globally 
synchronous.  Thus the 1990 figure - entirely schematic and left 
standing until it could be replaced by an alternate quantitative 
estimate, with meaningful uncertainty estimates (i.e., the Mann 
et al. paper, and others that have followed).

Now for the uncertainty estimates.  One would have to be very wary 
to apply uncertainty estimates to a qualitative figure, but if one
were to do so, then maybe a "ball park" 0.5 �C (about 1.0 �F) 
uncertainty might be applied.   If so, then one would have to 
conclude that is not possible to make a robust statement that the 
Middle Ages were warmer than the present, because the original 
estimate likely did not exceed 0.5�C above "present" (which at 
the time of writing of the report was about seventeen years ago).
[Note that I cannot find my copy of the original figure, so I 
would have to doublecheck the 0.5*C peak, but because the 
uncertainty estimate is also uncertain, I still stand by my 
conclusion about "inability to make a robust statement"

With respect to the uncertainty estimates prior to 1600 in the
Mann et al. paper,  the most that can be stated is the estimates
are substantially larger than for the later period just because
there are much fewer records.  The uncertainties for estimates
of annual temperature are about 0.5�C in Mann et al. (1999). 
However, the degree of uncertainty would decrease as records
are smoothed.  For example, forty year smoothing of the Mann
et al. record yields uncertainties of about 0.4�C.  Smoothing
comparable to the very smoothed 1990 IPCC figure has not, to my 
knowledge, been computed, but a reasonable guess would be that
it would be in the range of 0.2-0.3�C.


3. Please describe the peer review process for your most
recent publications. 

The peer review process has been pretty similar for my entire 
scientific career.  The paper goes out to 2-3 reviewers, who 
almost always provide anonymous peer reviews (i.e., they can 
say anything they want about it!).  If the reviewers like the 
paper but have questions, the editor will request that a 
revised manuscript be prepared that takes into account reviewer
concerns, and that a separate accounting be made to the editor
and reviewer about how specifically we addressed those concerned. 
Depending on the seriousness of the concerns, the editors will 
then either review the response themselves, or send it back to
the reviewers (if the concerns are minor he or she would 
probably not sent it back to the reviewers).  In some cases the 
reviewer may still be dissatisfied, in which case the authors 
would have to reiterate, but in many cases the reviewers will be
satisfied.  In some cases an editor might decide that if a 
reviewer is still dissatisfied, then the editor may choose to 
reject the paper.  Only after the editor is fully satisfied that 
reviewers and reconciled will the editor accept the paper.  In 
some cases the editor may accept a paper even if there are 
disagreements with reviewers, because a subject matter may be 
controversial and an editor may feel that all sides of an issue 
deserve a public airing.  In that case an editor may still 
accept a paper that has been opposed by a reviewer.


End of reply to the Honorable Bart Stupak


The Honorable Henry A. Waxman:

1. You were added to the witness list for this hearing on short 
notice, and therefore had very little time to prepare your 
testimony.  In reviewing your previously submitted testimony, is 
there anything you would like to clarify or supplement for the
record. 

Thank you for the opportunity to respond to this.  I am satisfied 
with most of the document but there are a few typos and 
grammatical mishaps I would like to correct.  I am also chagrined
by the choice of words I sometimes used to describe some of 
Dr. Wegman's report, and would like to change those.   I will 
therefore send you a slightly revised version of the original 
document that makes such changes.  If it is not possible to 
replace the original with the revision, then my statement 
herein is all I would like to add as a supplement.

End of Reply to the Honorable Henry A. Waxman






QUESTIONS SURROUNDING THE 'HOCKEY STICK' TEMPERATURE STUDIES: 
IMPLICATIONS FOR CLIMATE CHANGE ASSESSMENTS


THURSDAY, JULY 27, 2006

HOUSE OF REPRESENTATIVES,
COMMITTEE ON ENERGY AND COMMERCE,
SUBCOMMITTEE ON OVERSIGHT AND INVESTIGATIONS,
Washington, DC.


	The subcommittee met, pursuant to call, at 2:00 p.m., 
	in Room 2322 of the Rayburn House Office Building, 
	Hon. Ed Whitfield (Chairman) presiding.
	Members present: Representatives Stearns, Pickering, Bass, 
	Blackburn, Barton (ex officio), Stupak, Schakowsky, Inslee,
	Baldwin, Waxman, and Whitfield.
	Staff present: Mark Paoletta, Chief Counsel for Oversight 
	and Investigations; Peter Spencer, Professional Staff Member;
	Tom Feddo, Counsel; Matt Johnson, Legislative Clerk; 
	John Halliwell, Policy Coordinator; Clayton Matheson, 
	Analyst; Mike Abraham, Legislative Clerk; Edith Holleman, 
	Minority Counsel; David Vogel, Minority Research Assistant; 
	Chris Knauer, Minority Investigator; and Lorie Schmidt, 
	Minority Counsel.
	MR. WHITFIELD.  This hearing will come to order, and I 
	want to certainly welcome everyone to today's hearing.  
	This is the second day of our hearing regarding questions 
	about what we popularly call the hockey stick temperature 
	studies and the implications for climate change assessments.  
	We have reconvened this hearing to accommodate a key person
	in the matters before us, and that is Dr. Michael Mann of 
	Penn State University.  Dr. Mann was unable to attend the 
	session on the subject last week, and we are looking 
	forward to his testimony.
	As you know, he was one of the leaders in the methodology 
	of developing the methodology that developed the hockey 
	stick graph, and we hope we can continue to explore some 
	of the broader questions surrounding temperature 
	reconstruction findings, their use in the IPCC assessment, 
	and other issues that prompted our inquiry into this 
	matter last year.  Now the hockey stick graphic and the 
	underlying studies were influential in a prominent set of 
	findings by the IPCC, and really the hockey stick graphic 
	has become an icon for all those concerned about global 
	warming.
	In point of fact, from the very first set of findings on 
	the very first page of discussion in its 2001 summary for
	policy makers the IPCC states that 20th Century temperature 
	increases were likely the largest in 1000 years, and it was 
	likely that in the Northern Hemisphere the 1990s was the 
	warmest decade and 1998 the warmest year, a phrase that is 
	almost verbatim what Dr. Mann and his colleagues wrote in 
	their 1999 paper.  Next to these findings the IPCC summary
	then displays Dr. Mann and his colleagues' hockey stick 
	shaped temperature graph which helped this work prominently 
	and moved it into the public eye.
	Now let me just take a moment and make a few observations 
	about last week's hearing.  First, through our discussion
	of both the National Research Council report and the Wegman 
	report the original studies by Mann and his co-authors 
	appeared to be flawed, and cannot support the related 
	findings of the 2001 IPCC assessment.  Dr. Wegman's 
	independent committee found and reported that Dr. Mann and
	his co-authors incorrectly applied a statistical methodology 
	that would preferentially create hockey stick shapes.
	Dr. Wegman also found that more recent methodologies used in 
	temperature reconstruction studies may also generate
	problematic biases when determining temperature histories.  
	Now the National Research Council based on the Mann analysis 
	and newer supporting evidence finds that it is plausible that
	the Northern Hemisphere was warmer during the last few 
	decades of the 20th Century than during any period comparable
	in the preceding millennium.  Even less confidence, and I am
	quoting from their report, even less confidence can be placed 
	in the original conclusion by Mann that the 1990s are likely
	the warmest decade, and 1998 the warmest year.
	The NRC's panel review determined that Dr. Mann made in the
	words of the NRC witnesses inappropriate choices and that 
	the panel had much the same misgivings about Dr. Mann's work, 
	That was documented at much greater length by Dr. Wegman.  
	Moreover, both the NRC and Wegman reports essentially 
	corroborated the main criticisms raised by the McIntyre-McKitrick
	studies about Dr. Mann's initial hockey stick studies.  Now 
	while much attention was given to Dr. Wegman's social network 
	analysis, I think it is only fair to observe the limits of what
	he was trying to illustrate as he himself explained.
	Dr. Wegman was not seeking to impugn the integrity of any of 
	the scientists who work in the area, but it is clear that peer
	review somehow failed to pick up the flaws in the hockey stick 
	studies.  Dr. Wegman simply raises the possibilities that given 
	the evident publishing relationship among the authors of many of 
	the relevant works combined with the failure to involve 
	statisticians that Dr. Manns' peers may have been too close to
	the topic to scrutinize the studies as rigorously as they might
	have.
	Whatever the case, Dr. Manns' peers failed to catch the errors 
	that Wegman, the NRC and McIntyre identified.  Now this failure 
	as Dr. von Storch suggested last week may be less an issue with 
	the community of paleoclimatologists than with the journal 
	editors themselves.  Now finally I think it is important to 
	note that virtually everyone at the hearing last week, both 
	members and witnesses, took the view that criticisms of the
	hockey stick studies or of the peer review and assessment 
	process should not be considered as a judgment about the 
	changes in global temperature, but rather the issues at 
	hand concern legitimate questions about the rigor of 
	scientific analysis, the results of which ultimately reach
	policy makers and that is what we base our decision-making 
	decisions on.
	So the hockey stick story provides a clear case study into 
	what may be the lack of proper scrutiny, and the questions 
	last week about the independence of peer review or the gate
	keeping issues in my mind are legitimate.  And I think that 
	everyone would agree that we must be very careful and make 
	sure that when we do these analyses and they receive the 
	publicity that they do that they be scientifically based and
	as close to accurate as possible.
	Now in addition to Dr. Mann, both Dr. Wegman and 
	Dr. McIntyre are returning to recap their testimony and to 
	answer any questions related to their work, and certainly 
	Dr. Mann may want to raise some issues regarding what you 
	all said.  We have a few additional panelists as well.  As 
	we were preparing this panel, some have been suggested by 
	the minority side, and I am not sure which ones, but I want
	to welcome Dr. John Christy, the Director of the Earth 
	System Science Center, and an Alabama State climatologist at
	the University of Alabama, Huntsville, and Dr. Gulledge of
	the Pew Center for Climate Change.  And then finally I would
	like to recognize Dr. Ralph Cicerone, who is the President 
	of the National Academy of Sciences, and happened to be in 
	the same fraternity that I was, so, Dr. Cicerone, welcome.
	And he has been instrumental in the National Academy's focus
	on climate change research in recent years.  Indeed, he 
	chaired the National Research Council's 2001 report for 
	President Bush that helped pave the way for the United States
	to conduct its own climate change assessment.  I want to 
	welcome all of you.  Thank you for your time.  We look 
	forward to your testimony.  And I yield and recognize the 
	distinguished ranking member, Mr. Stupak.
	[The prepared statement of Hon. Ed Whitfield follows:]

PREPARED STATEMENT OF THE HON. ED WHITFIELD, CHAIRMAN, SUBCOMMITTEE 
ON OVERSIGHT AND INVESTIGATIONS

Good afternoon and welcome to a second day of our hearing regarding
questions about what we popularly call the "hockey stick" temperature
studies and the implications for climate change assessments.  
We've reconvened this hearing to accommodate a key person in the 
matters before us, Dr. Michael Mann, of Penn State University.  
Dr. Mann was unable to attend the informative session on this subject 
last week. Although Dr. Thomas Crowley - Dr. Mann's personally 
recommended replacement - did testify, we are providing Dr. Mann the 
opportunity to discuss his work and respond to some of the views 
expressed about his work. 
Welcome Dr. Mann, I'm looking forward to your testimony and 
participation.  I hope we can continue to explore some of the broader
questions surrounding temperature reconstruction findings, their use
in the IPCC assessment, and other issues that prompted our inquiry
into this matter last year.
 	The hockey stick graphic and the underlying studies were 
 	influential in a prominent set of findings by the IPCC.  In 
 	point of fact, from the very first set of findings on the
 	very first page of discussion in its 2001 Summary for 
 	Policymakers, the IPCC states that 20th Century temperature 
 	increases were likely the largest in 1,000 years and it was 
 	[quote] "likely that, in the Northern Hemisphere, the 1990s 
 	was the warmest decade and 1998 the warmest year," a phrase 
 	that is almost verbatim what Dr. Mann and his colleagues 
 	wrote in their 1999 paper. Next to these findings, the IPCC 
 	Summary then displays Dr. Mann and his colleagues' hockey 
 	stick-shaped temperature graph, which helped this work 
 	prominently into the public eye. 
Let me take a moment and make few observations about last week's 
hearing. 
First, through our discussion of both the National Research Council 
report and the Wegman report, we established that the original 
studies by Mann and his coauthors were flawed, and could not support 
the related findings of the 2001 IPCC assessment.  Dr. Wegman's 
independent committee found and reported that Dr. Mann and his
coauthors incorrectly applied a statistical methodology that would 
preferentially create hockey stick shapes.  Dr. Wegman also found 
that more recent methodologies used in temperature reconstruction 
studies may also generate problematic biases when determining 
temperature histories. 
The National Research Council, upon its review of the current state 
of science on this subject, likewise found that the hockey stick 
studies could not support the 2001 IPCC finding drawn from them.  
The NRC panel's review determined that Dr. Mann made, in the words
of the NRC witnesses, "inappropriate" choices, and that the panel 
had "much the same misgivings about [Dr. Mann's] work that was 
documented at much greater length by Dr. Wegman."  
Moreover, both the NRC and Wegman reports essentially corroborated 
the main criticisms raised by the McIntyre-McKitrick studies about 
Dr. Mann's initial hockey stick studies.  
While much attention was given to Dr. Wegman's social network 
analysis, I think it is only fair to observe the limits of what he
was trying to illustrate, as he himself tried to explain.  
Dr. Wegman was not seeking to impugn the integrity of any of the 
scientists who work in this area, but it is clear that peer review 
somehow failed to pick up the flaws in the hockey stick studies.  
Dr. Wegman simply raises the possibility that, given the evident 
publishing relationship among the authors of many of the relevant
works, combined with the failure to involve statisticians, 
Dr. Mann's peers may have been too close to the topic to 
scrutinize the studies as rigorously as they might have. Whatever 
the case, Dr. Mann's peers failed to catch the errors Wegman, the
NRC, and McIntyre identified.  
This failure, as Dr. von Storch suggested last week, may be less 
an issue with the community of paleoclimatologists, than with the
journal editors themselves.  The Committee can remain cautious 
about Dr. Wegman's social network analysis, as he is, and still
legitimately raise the broader question about the rigor of review
and breadth of reviewers in this field.  
Finally, I think it is important to note that virtually everyone
at the hearing last week - both members and witnesses - took the 
view that criticisms of the hockey stick studies or of the 
peer-review and assessment process should not be construed as a 
judgment about the changes in global temperatures.
Rather, the issues at hand concern legitimate questions about the
rigor of scientific analysis, the results of which ultimately reach
policy makers.  The hockey stick story provides a clear case study
into the lack of proper scrutiny, and the questions last week about
the independence of peer-review, or the "gate keeping" issues, were 
entirely legitimate.  I hope that as we proceed today, we keep this
in mind.  And I hope that we can all reach agreement on ways to 
improve the process. 
Let me note that we have, in addition to Dr. Mann, both Dr. Wegman
and Mr. McIntyre returning to recap their testimony and to answer 
questions related to their work, if necessary.  Both of them 
graciously agreed to adjust their busy schedules, including family 
and work obligations, to return today at our request so that 
Dr. Mann could confront his critics.  Thank you very much for 
coming back. 
We have a few additional panelists as well.  As we were preparing 
this panel, our minority counterparts requested an additional 
witness.  In the event, we accommodated their requests so that we 
could have as informative and balanced a panel as possible.   
So let me welcome Dr. John Christy, the Director of the Earth System
Science Center and Alabama State Climatologist at the University of
Alabama, Huntsville and Dr. Jay Gulledge, of the Pew Center for 
Climate Change.   
Finally, I'd like to recognize a most-distinguished witness,
Dr. Ralph Cicerone [sisserone], President of the National Academy 
of Sciences.  Dr. Cicerone has been instrumental in the National 
Academies' focus on climate change research in recent years. Indeed,
he chaired the National Research Council's 2001 report for President 
Bush that helped pave the way for the United States to conduct its 
own climate change assessments.  
Welcome Dr. Cicerone, and welcome all the witnesses, I look forward 
to another informative panel. 
I now yield to my distinguished Ranking Member, Mr. Stupak.

	MR. STUPAK.  Thank you, Mr. Chairman.  Today we are holding
	a very strange hearing.  Originally scheduled to give 
	Dr. Michael Mann a chance to respond to critics who provided
	testimony to this committee last week, this hearing has now 
	expanded to allow these critics to attack the very science 
	of global warming.  Witnesses reappearing in the committee 
	today, once commissioned by the Majority to do a very limited 
	and biased review, had attempted to discredit Dr. Mann's 
	8-year old study on reconstruction of surface temperatures 
	over the last thousand years, and his conclusion that the
	earth is warming at an unprecedented rate.
	However, as Dr. North testified last week, a comprehensive 
	review of temperature reconstruction research by the National
	Academy of Science at the request of the Science Committee 
	found that there were numerous other studies concluding that
	the Earth is warming at an unprecedented rate.  Now instead 
	of allowing Dr. Mann to respond to last week's allegations, 
	two of our witnesses, apparently unhappy with the outcome of 
	last week's hearing have decided to rewrite and expand their
	testimony to raise new issues, new complaints, and new 
	questions.
	This re-written testimony is no longer limited to Dr. Mann's 
	statistical methods and their own work, but also includes 
	areas of climatology totally outside their expertise.  As a 
	result, it appears that these critics have lost interest in 
	simply attacking Dr. Mann's work.  Now the purpose of today's 
	hearing is to cast doubt on all scientific evidence of global
	warming.  Mr. Chairman, if we are going to discuss the larger
	issue of global warming, which many of us on this side would 
	be happy to do, we need to put more time and effort into 
	putting together a series of well thought out hearings with 
	adequate time for witnesses and staff to prepare.
	If the Majority were truly interested only in temperature 
	reconstruction over the past thousand years we could have heard
	from all of the scientists who have worked on this topic both
	before and after Dr. Mann's original 1998 and 1999 publications.
	Instead, the Majority asked Dr. Wegman, a statistician with no
	expertise in paleoclimatology, to verify only Mr. McIntyre's
	critique of Dr. Mann's initial work.  Dr. Wegman was not even
	asked if Dr. Mann's conclusions would change if the criticisms
	were incorporated and the analysis were re-created, nor did he
	volunteer to do that.
	Other climatologists have recreated Dr. Mann's work and have 
	come to the same conclusions using both similar and different 
	data sets and methodologies.  Dr. Wegman, who has not reviewed 
	this work and did not discuss any of the studies in his 
	testimony last week, will try to discredit all of these 
	studies with an unsupported hypothesis questioning the 
	independence of a large group of scientists work.
	Another witness we will hear from today, Dr. Christy, has 
	supported the science behind global warming but will argue 
	that by acting to curb global warming we may deny the poor 
	in other countries the advantages that we have here in America.
	This is also the argument of a new group, the Interfaith 
	Stewardship Alliance, but we have not heard from the alliance 
	when trying to provide low-income emergency assistance for
	people in my district.
	However, the threat of rising temperatures and the negative 
	results of them, including diminished agricultural production,
	and quite possibly the flooding of vast heavily populated 
	coastal areas due to the melting of the polar ice caps, can
	be far more of a threat to developing countries than efforts
	to limit harmful industrial emissions.  The National Climatic
	Data Center has recently confirmed that the first half of 
	2006 was the warmest first half of any year in the United 
	States since 1895.  This warming trend is continuing.
	Today's headline in the Washington Post, I should say 
	Tuesday's headline in the Washington Post, "Deadly Heat 
	Continues in California."  The morgue in Fresno, California
	has many bodies of elderly people overcome by heat.  
	Unprecedented temperatures have been recorded recently in 
	Oregon and South Dakota, among other places.  Forty-five 
	percent of the United States is in moderate to extreme 
	drought conditions.  These conditions have spawned more than 
	50,000 wildfires burning approximately 4 million acres.
	Congress is not particularly capable to judge science that 
	deals with linear regressions, Pearson's R square, centering
	and de-centering, or regulized expectation maximization.  As 
	Dr. Cicerone will remind us, that is why Congress created the
	National Academy of Science.  We are, however, able to 
	understand the strategy of Exxon Mobil, outlined in their 
	1998 action plan.  This plan argued, and I quote, "victory 
	will be achieved when average citizens understand, recognize 
	uncertainties in climate science."  This appears to be the 
	focus of today's hearing, to confuse and complicate the 
	findings of climate scientists, and Dr. Mann is unfortunately 
	in the crosshairs.  I yield back the balance of my time.
	[Additional information submitted for the record follows:]




	MR. WHITFIELD.  The chair recognizes the chairman of the Energy 
	and Commerce Committee, Mr. Barton of Texas.
	CHAIRMAN BARTON.  Thank you, Mr. Chairman, and thank you for 
	this hearing.  I want to thank our witnesses for being here, 
	some of them for the second time.  We are obviously glad to 
	have Dr. Mann here.  We appreciate you being able to join 
	us.  It is clear from last week's hearing on global climate 
	temperature studies that we face issues involving more than 
	the particulars of Dr. Mann's specific hockey stick study.  
	However, it is the particulars of these studies and how 
	the existing climate assessment process has dealt with 
	them that got us here today.
	I appreciate the participation of this panel.  I am glad 
	that Dr. Ralph Cicerone is here.  He is the President of 
	the National Academy of Sciences.  I think he is going to 
	add significant weight and gravitus to the hearing today.  
	As you noted in your statement, Chairman Whitfield, last 
	week's hearing demonstrated why we as policymakers need to 
	understand the quality and the reliability of the science 
	on which we are urged to base public policy that is both 
	sweeping and costly.  Some very respected and authoritative 
	sources testified last week that Dr. Mann's studies were 
	flawed.  They couldn't support the findings for which they 
	were used in the United Nations Climate Change Assessment, 
	the IPCC.  Today I hope that we are going to examine some of 
	these issues in more detail.
	I recognize that additional work has been published that 
	supports the broad outline of some of those conclusions in 
	Dr. Mann's initial hockey stick study, but according to the 
	National Research Council even that subsequent work cannot 
	provide the level of confidence that IPCC placed upon the 
	original hockey stick analysis.  Nothing about the process 
	of turning observations into accepted theory is smooth.  It 
	has been said that the politics of small towns and big 
	universities are brutal.  They make us look amateurs by 
	comparison.  Looking at what is happening in this issue, I 
	think that might well be true.  Unfortunately, that is the
	way this science progresses.
	I not only accept it, bumps included, but, believe it or not, 
	I support it.  What I can't accept is the improbable notion 
	that this committee may not ask science or research-related 
	questions that bear on policy making when the answers could
	improve the information we use to reach the policy decisions 
	that we are elected to make.  It is just wrong to say that 
	questions are not permitted, free debate is improper or 
	that anyone who wonders if the scientific establishment 
	really has it right should be dismissed as anti-science or
	oblivious to the real risk of man-made climate change.
	This committee holds a very key role in any policy-making
	decision related to climate change.  As its Chairman, I 
	have an obligation to be cognizant of that and to do 
	everything possible to get a fair record but also get into 
	the details of some of the theories that the policies, the 
	recommended policies, are supposedly based upon.  We are 
	interested in Dr. Mann's work, not because of Dr. Mann, as 
	nice a fellow as he may or may not be; we are interested 
	in Dr. Mann's work because it was the original.  It was 
	seminal.  It is referred to.
	I haven't seen Vice President Gore's movie, but I am told 
	in that movie Dr. Mann's hockey stick diagram is shown 
	repeatedly.  It is only fair to take a look at the original 
	seminal work to see if it really lives up to what it claims 
	to be.  During our last hearing, we were shrugged at for 
	asking about that particular study saying it was too early, 
	too distant, but the fact is that that particular study is
	the study that much of the latter conclusions have been 
	based upon.  It is only common sense to take a look at 
	it.  We are going to work on the issue, and if it turns 
	out that that study is not the right study and if there 
	are more current studies that are more correct, we will 
	take a look at those too and we will find out what the 
	truth is.  The truth is the truth.  The truth may be 
	inconvenient.  It may be politically incorrect, but the 
	truth is the truth.
	A couple of months ago Chairman Whitfield and I asked 
	the U.S. Government Accountability Office to help us 
	examine Federal data sharing policies especially as they
	related to climate change research.  This work will help 
	our efforts to improve the exchange of scientific data
	and other essential information, which as we have seen 
	has been a particular problem in the climate change 
	arena.  When the dust settles on these hearings, I am 
	going to prepare a request to the National Research 
	Council, which Dr. Cicerone who is with us today 
	chairs, to take some of the issues that Dr. Wegman and 
	others have raised and take a look at it.
	I am going to ask for a study to assess how to include 
	a wider spectrum of scientific disciplines in climate 
	change research so that we can be enlightened by the 
	very best work across the field of scientific 
	research.  I am going to ask that this study be 
	coordinated and run though the NRC's Division on 
	Engineering and Physical Sciences so that we can 
	ensure that the disciplines like mathematics and 
	physics and statistics participate up front.  I would 
	be happy to hear any of Dr. Cicerone's comments on 
	that today as we go forward.
	Letting a wider scientific community address questions 
	about climate change assessments can only help the 
	process and improve the results.  We have an obligation 
	on this committee on behalf of the American people to 
	ensure that the decision makers have the best 
	information possible, not just the politically correct 
	information.  I want to thank again our panel for 
	coming.  I want to especially thank Dr. Mann for 
	changing his schedule to be here.  I look forward to a 
	very productive exchange of views as we go forward 
	today.  Thank you, Mr. Chairman.
	[The prepared statement of Hon. Joe Barton follows:]

PREPARED STATEMENT OF THE HON. JOE BARTON, CHAIRMAN, COMMITTEE 
ON ENERGY AND COMMERCE

Thank you, Chairman Whitfield.  It is clear from last week's 
hearing on global climate temperature studies that we face 
issues involving much more than the particulars of Dr. Mann's 
"hockey stick" studies.  However, it is the particulars of 
these studies - and how the existing climate assessment process 
dealt with them - that got us here today.  And so I appreciate 
that Dr. Mann accepted our invitation to lay out his important 
work on global temperature reconstruction, as well as to answer 
our broader questions concerning climate change assessments.   
I also appreciate the participation and perspective of our 
distinguished panelists today, including Dr. Ralph Cicerone, 
the President of the National Academy of Sciences.  Let me also 
welcome back Dr. Wegman and Mr. McIntyre, who testified last 
week.  
  	As you noted, Chairman Whitfield, last week's hearing 
  	demonstrated why we as policymakers need to understand 
  	the quality and reliability of the science on which 
  	we are urged to base policy that is both sweeping
  	and costly.  Some very respected and authoritative 
  	sources testified last week that Dr. Mann's studies 
  	were flawed, and that they couldn't support the 
  	findings for which they were used by the United 
  	Nation's climate change assessment, the IPCC.   
  	Today I hope we can examine some of these issues a 
  	bit more.  
I do recognize that additional work has been published that 
supports in broad outline some of the conclusions of 
Dr. Mann's initial "hockey stick" studies.  But according to 
the National Research Council, even that subsequent work 
cannot provide the level of confidence that IPCC placed upon
the hockey stick studies.  
Nothing about the process of turning observations into 
accepted theories is smooth.  It has been said that the 
politics of small towns and big universities are brutal 
enough to make our kind look amateurish by comparison, and I 
think that might be true.   In any case, that's the way 
science progresses.  I not only accept it -- bumps 
included -- but I support it.  
What I can't accept is the improbable notion that this 
committee may not ask science- or research-related questions 
that bear on policymaking when the answers could improve the 
information we use to reach those policy decisions.  It is 
just wrong to say that questions are not permitted, or that 
free debate is improper, or that anyone who wonders if the 
scientific establishment really has it right should be 
dismissed as anti-science or oblivious to the real risks of 
manmade climate change.  Because this Committee holds a key 
role in any policymaking relating to climate change, as its 
Chairman I will do everything I can to ensure that the very 
best information on these issues is available to us.
We're interested in Dr. Mann's work because it is seminal.  
During our last hearing, some shrugged at it as distant and 
early, but the fact is that Dr. Mann's conclusions influence
both current research and global policy.  As we try to close 
the loop on our concerns, I also want to emphasize that this 
Committee will continue to work on the issues raised here, 
to help ensure the reliability of future scientific assessments.    
A couple of months ago, Chairman Whitfield and I asked the 
U.S. Government Accountability Office to help us examine 
federal data sharing policies, especially as they related to 
climate change research.  This work will help our efforts to 
improve the exchange of scientific data and other essential 
information - which as we have seen has been a particular 
problem in this climate change arena.  
Also, when the dust settles on these hearings, I'm going to 
prepare a request to the National Research Council, which 
Dr. Cicerone chairs, to take on some of the issues that
Dr. Wegman and others have raised for us.  I will ask for a 
study that assesses how to include a wider spectrum of 
scientific disciplines in climate change research so that we 
can be enlightened by the very best work that our scientists 
conduct, all of them.  I'll ask that this study be coordinated 
and run though the NRC's Division on Engineering and Physical 
Sciences, so that we can ensure that disciplines like 
mathematics, physics, and statistics participate up front.  
I'll welcome Dr. Cicerone's perspective on this today, so that
we can formulate an effective request.
Letting a wider scientific community address questions about 
climate change assessments can only help the process and 
improve the results.  We have an obligation on this Committee 
to ensure that America's decision-makers have the best 
information possible.  
Thank you all for coming to testify today.  I yield back the 
remainder of my time. 

	MR. WHITFIELD.  Mr. Waxman of California is recognized.
	MR. WAXMAN.  Thank you very much, Mr. Chairman.  The 
	magnitude of global warming and the crisis that we are 
	facing on this planet demands a serious response from 
	this body. We should be holding hearings to understand 
	the ramifications of recent studies detailing the 
	harmful effects of global warming that we are seeing 
	all around us from increased wildfires in the west to 
	more intense hurricanes, more acidic oceans.  We should
	examine practical steps this Congress and the 
	Administration must take to reduce global warming 
	pollution.  We should explore how best to re-engage 
	with the international community on addressing this 
	problem because this is going to require all countries 
	to do their part.
	We should investigate the well-funded effort by certain 
	oil companies to manufacture controversy and cast doubt
	on the reality of global warming and the human 
	contribution to it.  This hearing today is the third 
	that this committee has held on the issue of global 
	warming.  We are the committee that would move 
	legislation forward on this subject, and this is really 
	a continuation of the second one, which was last week.
	In that hearing, the Republican majority attempted to 
	discredit a respected climate scientist and a study 
	he published 8 years ago.  Well, not only is this use of 
	the subcommittee ridiculous and unfair, it is also a 
	waste.  Yet, despite its intended focus, today's hearing 
	does give us the opportunity to learn more about the 
	current state of climate science, and I am looking 
	forward to hearing the views of Dr. Ralph Cicerone, who 
	is the President of the National Academy of Sciences, 
	and the Chairman of the National Research Council and a
	fraternity brother of the Chairman of this subcommittee,
	and he is an eminent climate scientist.
	I am also very pleased we are going to hear from 
	Dr. Mann, who is one of the world's most distinguished 
	paleoclimatologists.  Eight years ago, Dr. Mann and his
	colleagues published a groundbreaking study that 
	reconstructed the temperature of the Earth over the past 
	600 years using proxy data such as tree rings.  Since 
	2002, Dr. Mann has published another half dozen papers 
	revising and building on his work.  These latter studies, 
	as well as many independent paleoclimate reconstructions 
	by other scientists continue to find the same thing.  The 
	warmer temperatures in the last few decades are 
	unprecedented compared to anything we have experienced in 
	the last thousand years.
	Now the Majority, the Republicans, won't use this hearing 
	to examine Dr. Mann's recent studies or the independent 
	confirmation of its work.  Instead, they want to focus 
	exclusively on his original work in 1998 and 1999 because 
	they think they can find a statistical flaw.  So what? 
	The strategy is not a subtle one.  Because they think they
	found a flaw in one study out of thousands the Majority 
	wants to build the one study into the pillar of the 
	scientific case for global warming.  The Chairman seems 
	to think that if he can discredit one climate scientist, 
	Dr. Mann, he can cast doubt on all the climate change 
	research.  In effect, it is back to the tactics of the 
	tobacco industry.
	I remember well when they would send their scientists to 
	come in and just cast a little doubt about whether 
	smoking cigarettes really do cause cancer, whether there 
	is really a medical problem.  I think intimidation is 
	part of the strategy we are seeing.  This subcommittee 
	launched this campaign against Dr. Mann and several of 
	his colleagues last year by demanding to know the source 
	of funding for every study they had ever conducted and 
	demanding that they turn over all the data for all their 
	research.  These are bullying tactics and they drew highly
	unusual protests from the American Association for the 
	Advancement of Science, the National Academy of Sciences, 
	and the Republican Chairman of the House Science Committee, 
	among others.
	Well, we are having Dr. Mann here today.  It is important 
	that he be here.  Last week we held a hearing where he was 
	criticized.  Now he has got his accusers back again.  They 
	couldn't wait to have the hearing where all of them were 
	together.  But this subcommittee will hear about Dr. Mann's 
	work from him and those who criticize him.  The subcommittee 
	will hear the many other completely independent lines of 
	evidence that support the reality of global warming and the 
	role of humans in causing it.
	The scientific evidence of human contribution to global 
	warming is clear and compelling.  The only open question is 
	how long members of this subcommittee will keep pretending 
	that it doesn't exist.  I don't know how many hearings we 
	are going to have on the subject of Dr. Mann's one study in 
	1998, but it seems to me that as we look around this country 
	and in in fact all around the world just today we are seeing 
	a continuation of some of the highest temperatures on 
	record.  We ought to get serious about this matter of 
	global warming and climate change.  We ought to be holding 
	hearings about the important issues that relate to it and 
	not this one issue over and over again.  I yield back the 
	balance of my time.
	MR. WHITFIELD.  I would point out that even though 
	Dr. Mann was not here last week, he did suggest that 
	Dr. Crowley come on his behalf, and Dr. Crowley did 
	testify.  I recognize the gentleman from Mississippi for 
	an opening statement.
	MR. PICKERING.  Mr. Chairman, I thank you for this hearing, 
	and I yield back my time.  I want to get to the panel as 
	quickly as possible.
	MR. WHITFIELD.  Mrs. Blackburn, you are recognized.
	MRS. BLACKBURN.  Thank you, Mr. Chairman.  I do want to 
	thank you for the hearing, and I want to welcome all of our 
	witnesses.  I want to thank you for being patient with us 
	and allowing us some more time to visit with you.  At last 
	week's hearing we did hear testimony regarding errors in 
	Dr. Mann's 1998 and 1999 hockey stick report, and today we 
	are going to be able to hear Dr. Mann's response to that. 
	We are pleased to have him join us and are looking forward 
	to that response.
	I do still have some questions, and I find some of the 
	circumstances involving Dr. Mann's paper a little bit 
	disconcerting.  It seems that it could only be corroborated 
	by a social network and that seems to be a problem.  It is 
	difficult for me to see how scientists and policy makers 
	could agree with and legislate anything based on research 
	which by all appearances cannot be corroborated by 
	independent review.  Second, it is apparent that until now 
	no independent experts have examined Dr. Mann's data and 
	statistical procedures.
	Again, it is difficult to rely on data that has not been 
	rigorously examined for consistency and validity.  I am 
	looking forward to some answers on that, and I would not 
	say that it is intimidation that has brought questions 
	forward.  I would say it really is curiosity and a desire 
	to know answers.  Finally, I have noticed a trend, and this 
	trend raises questions, and it is that trend by where a close 
	group of scientists who support climate change theory tend to 
	be serving as the primary peer reviewers and the lack of that 
	independent review, and those reviewers are checking one 
	another's work.  And it may be strictly coincidence but again 
	it does not lead me to believe these papers are being as 
	thoroughly examined as they might by those that are 
	independent, and the public is not being as well served as 
	they should of what they are told is scientific proof.
	It is critical that even if we should discount the 1990 IPCC 
	report, recent analysis of over 250 climate studies and 
	historical records showed that the medieval warm period was 
	global and higher than present day temperature, and they both 
	concurred that the little Ice Age occurred worldwide and 
	produced a substantial drop in the average temperature.  Also, 
	satellite data and the U.S. surface record indicate that the 
	Earth's temperature in the past 100 years has undergone both 
	warming and cooling trends.
	Last week I mentioned in 1960 when I was in high school there 
	was a commonly held premise that we were returning to the Ice 
	Age and by the time I reached my current age and a new 
	millennium dawned we would be in a perpetual winter with food 
	shortages, et cetera.  So we had that, that we were dealing 
	with in a cooling trend and that we were being taught as 
	high schoolers in the '60s, but recent trends seemed to be 
	caused by solar activity in the 1990 El Nino, not necessarily 
	by the increase of green house gas emissions.
	Mr. Chairman, policy makers depend on the integrity of data. 
	The public depends on the integrity of data.  Educational 
	institutions depend on the integrity of data and results, 
	and I believe it is necessary and proper for us to set 
	quality standards for data release and verification for any 
	research that receives Federal funds.  Thank you, and I yield 
	back.
	MR. WHITFIELD.  Thank you.  I recognize Ms. Baldwin of 
	Wisconsin for her opening statement.
	MS. BALDWIN.  Thank you, Mr. Chairman.  Again, we are here 
	discussing global warming, and again I think our focus is off 
	target.  Rather than addressing action steps to address global 
	warming in a bipartisan coordinated and effective manner, we 
	are covering up the real issues with irrelevant chatter about 
	the basis of a study that was released almost a decade ago, a 
	study that has been updated, revised, reviewed, and validated 
	time and time again in recent years.  Unfortunately, the goal
	of these hearings is not to show that there is an abundance 
	of science demonstrating that the Earth is warming at an 
	unprecedented rate, that carbon dioxide levels are rising, 
	and that human activities are largely the cause.  Rather it 
	is an attempt to poke holes in an old study and divert 
	attention away from the decisions that we as policy makers 
	often have to make.
	Decisions like should we let big business profits override 
	human interests or should our policy time horizon be a few 
	short years or should we be thinking about protecting 
	generations yet to come.  For if this hearing and even 
	Dr. Wegman's analysis were not commissioned for political 
	reasons but rather out of a concern that study after study 
	shows the Earth is warming, sea levels rising and snow caps 
	melting, then we would be focusing on current information. 
	The committee would have asked Dr. Wegman to review 
	Dr. Mann's and other reputable scientists' work that has 
	been published in recent years.  But this is not what the 
	committee requested nor what Dr. Wegman studied.
	Instead, the focus is on Dr. Mann's 1998 and 1999 study that 
	contains acknowledged flaws.  The argument made over the 
	last week against Dr. Mann's early work are old and tired 
	and really I believe their desperate attempts to divert 
	attention away from what countless experts agree, that 
	climate change is happening, the global warming is 
	happening, and that our actions, things we as humans do 
	each and every day, contribute to this crisis.  It is 
	troubling that the United States appears to be alone on this 
	island of skeptics.  More troubling is that we are virtually 
	alone and are inaction.
	Despite being the largest consumer of electricity, oil, and 
	natural gas, we refuse to take bold steps that will allow us 
	to lead the world on environmental issues, yet countries with 
	significantly smaller footprints on the world are making 
	incredible advances that improve the quality of the air they 
	breathe, the food and water they consume, and the lifestyles 
	they lead.  Let me just give a couple of examples.  China's 
	fuel economy standards are more stringent than those in 
	Australia, Canada, California, and the United States.  
	Meanwhile, we haven't increased our fuel economy standards in 
	over 20 years.
	Brazil's ethanol program, the largest in the world, has 
	created rural jobs, reduced air pollution, and reduced 
	Brazil's green house gas emissions while reducing its 
	dependence on imported oil, yet we refuse to take necessary 
	steps to reduce our dependence on foreign energy.  Denmark 
	has the highest utilization rate of wind energy in the world 
	with wind producing approximately 20 percent of Danish 
	electrical consumption.  Meanwhile, our government has issued 
	notices of presumed hazard to wind developers in the Midwest
	halting and threatening to permanently derail wind production.
	And just yesterday Northern Ireland announced that all new 
	homes built starting in 2008 must have solar roof panels. In 
	this country, I look forward to the day when we take this bold 
	step.  Mr. Chairman, we could spend the next few hours 
	discussing the fine points of Dr. Mann's 1998 and 1999 study, 
	and Dr. Wegman's analysis of it, or we could focus on what is 
	really going on.  The Earth's temperature is rising and has 
	reached levels higher than ever recorded.  It is true 
	regardless of whether you center, de-center, or average the 
	data each and every way you read it the conclusion is the 
	same.
	False logic will not bring us closer to an understanding of 
	the scientific truth, so let's stop politicizing science.  
	Rather, let's show our commitment to our environment which 
	we have a moral and ethical obligation to protect.  I hope 
	that today we will take steps in that right direction but I 
	fear we will not.  I yield back, Mr. Chairman.
	MR. WHITFIELD.  Thank you, Ms. Baldwin.  I recognize 
	Mr. Stearns of Florida.
	MR. STEARNS.  Thank you, Mr. Chairman, and I thank you for 
	having this hearing.  Listening to the folks on the other 
	side, I would say to my colleague from California asking why 
	aren't we spending our time developing legislation, I would 
	say it is probably incumbent upon us as Chairman Barton 
	pointed out to find out if the facts are correct.  We have 
	from the last hearing some inquiry that shows there 
	potentially exists some dubious research particularly embodied 
	on the hockey stick effect that shows a huge global warning 
	in our period.
	Now if you look at the data and you go to the recent release
	from the National Research Council, Thursday, June 22, 2006,
	it shows that from the period 1400 A.D. to 1900 A.D. were in 
	a little Ice Age, but when you go back further back to 1000 
	A.D. to 1400 A.D. we were in a warm period, so is it possible 
	that what we are seeing here is sinusoidal and that perhaps 
	we should inquire if this hockey stick graph is the basis for
	this alarm that we should start developing legislation
	immediately.  Obviously, it is the centerpiece of movies.  
	It is the centerpiece of documents that have been popular, 
	but what it shows is that the temperatures were stable in 
	other parts of our period and were much higher in the 
	medieval and obviously there was not the human population, 
	there was not the gasoline that supposedly is driving this 
	warming period now.
	So I think we owe it to our constituents.  We owe it to 
	all the Americans to find out if the policy decision for 
	this hockey stick is accurate so I think what we are doing 
	today, Mr. Chairman, is just simply trying to develop an 
	accurate understanding of what is out there.  Now we had the 
	hearing last week and we heard from Dr. Wegman.  This report 
	provided an independent critique of the statistical method 
	of Dr. Mann, which shows that his information basically 
	produced the hockey stick.  Dr. Mann asserted that the 
	increase in the temperatures in the Northern Hemisphere in 
	the 20th Century is likely to have been the largest of any 
	century during the past 1,000 years.
	The report also found that 1990 was the warmest decade and 
	1998 the warmest year of the millennium.  Dr. Mann's claims 
	are repeated so often they are now considered facts, but as 
	often the case with statistics, a deeper look at some of 
	these claims show that perhaps there is more than meets the 
	eye.  Dr. Wegman's final report found that Dr. Mann misused
	certain statistical methods in his studies which 
	inappropriately selected hockey stick shapes in the 
	temperature history.  Dr. Wegman concludes that Dr. Mann's 
	work cannot support the claim that the 1990s were the warmest
	decade of the millennium.
	Specifically, Dr. Wegman found that the temperature proxies 
	used by Dr. Mann are incorrectly centered on the mean of the
	period 1902 to 1995 rather than on the whole time period.  
	Because the hockey stick proxies are centered too low, they 
	will exhibit a larger affected variance allowing the graph 
	to exhibit a much more dramatic jump in average temperature. 
	The net effect of de-centering in Dr. Mann's study is to 
	produce this hockey stick shape.  Centering on the overall 
	mean is a critical factor in using the principal component
	of methodology properly according to Dr. Wegman.
	So that is sort of in a nutshell what we have here so by 
	golly, I think it is worthwhile to have a second hearing on
	this, Mr. Chairman, and to try to understand what is 
	happening here, and at the same time not be overly critical 
	of anybody because in the end all we want is the truth, and 
	to understand if we are in an emergency situation or 
	basically we are in a period where there are highs and lows 
	in this earth temperature.  And, in fact, in the report that 
	has come out with the working group of the Intergovernmental
	Panel on Climate Change, which was used in many reports, it 
	shows the last 140 years the temperature of the Earth has 
	gone up 1.5 degrees Fahrenheit, so that is 140 years.  Now 
	that could be coming off a cold cycle which means 1.5 
	degrees Fahrenheit is even more negligible.
	So the question of global warming is something we should 
	look at, and I think before we pass legislation or as 
	Ms. Baldwin talked about this chattering irrelevance, we 
	should find out what is relevant to the studies and if they 
	make sense before we pass legislation.  I yield back, 
	Mr. Chairman.
	MR. WHITFIELD.  Thank you.  The chair recognizes 
	s. Schakowsky of Illinois.
	MS. SCHAKOWSKY.  Thank you, Mr. Chairman.  I find this 
	hearing really depressing among other things.  There is a
	sense that somehow there is a pretense that what we are 
	engaged in here is some sort of scientific-like inquiry 
	but the fact of the matter is that the scientific 
	community has reached consensus.  You can say anything 
	you want at this hearing but that is simply the truth.  
	I want to read something from Al Gore's book but lest you 
	think it is Al Gore's words it is a statement of 48 Nobel 
	Prize winning scientists.  It says, "By ignoring scientific
	consensus on critical issues such as global climate change 
	President Bush and his Administration are threatening the
	Earth's future."
	I am not so upset about a waste of time.  We do plenty of 
	that around here.  But I am depressed about it because that 
	is what is at stake here, the time that we are spending 
	here.  I also just want to say since we are getting into 
	this petty he said, you said, back and forth, the charts that
	Al Gore said--he talked about this teacher of his, 
	Dr. Roger Ravelle.  It was his chart that he first 
	presented.  When he showed a chart that looks very similar
	to our hockey stick it was Dr. Lonnie Thompson's study that
	he was talking about.  These have been repeated over and 
	over again.  How many times, 928 peer reviewed articles 
	dealing with climate change published in scientific journals 
	during the previous 10 years, percentage in doubt as to the 
	cause of global warming, 0 percent.
	The answer is in.  And so it seems to me unless somewhere 
	there, and Dr. Wegman already has told us over and over 
	again, he is nearly a paleoclimatologist, he is not a 
	climate scientist of any sort, unless someone can tell us 
	that the planet is not warming and that it is not that the 
	warming, I am sure no one would do that, that the warming 
	is not at least in part attributable to human activity then
	what we should be talking about is what we are going to do 
	to address the problem.  What do we know?  We know Greenland 
	is melting.  We know that some of our districts could be 
	under water.  We know that human life as we know it could be 
	unsustainable in many ways on this planet.  Drought, more 
	severe storms, flooding, all the things, not to mention for 
	my littler grandchildren that polar bears are drowning and 
	different species of trees aren't going to be there.
	Look in magazines, the old National Geographics, to look at 
	the changing of the trees in the north.  This is happening. 
	So why we would be spending our time in what may be--fight 
	about it.  Fine.  Let the scientific community do whatever it 
	wants, Dr. Mann and his old study, and let Dr. Mann defend 
	himself, but what we should be sitting down and doing, what 
	are those strategies that we can employ to decrease the 
	effects of global warming so that life as we know--so what 
	if it is normal?  So what if--but if human activity is 
	contributing to a greater than normal warming or even an 
	upswing right now and the life that we have established on 
	this planet is in danger then we ought to be thinking about 
	the ways that we address this problem.
	And Mr. Waxman talked about the tobacco companies.  Well,
	we have now here on July 27, 2006, ABC News--ever wonder 
	why so many people still seem confused about global 
	warming?  This is a quote from the--the answer appears to 
	be that confusion leads to profit especially if you are in 
	some parts of the energy business.  One Colorado electric 
	cooperative has openly admitted that it has paid $100,000 
	to a university academic who prides himself on being a 
	global warming skeptic.  Intermountain Rural Electric 
	Association is heavily invested in power plants that burn 
	coal, one of the chief sources of greenhouse gases that 
	scientists agree is quickly pushing Earth's average 
	temperature to dangerous levels.
	Scientists and consumer advocates say the co-op is trying 
	to confuse its clients about the virtually total 
	scientific consensus on the causes of global warming.  Now 
	virtually totally scientific consensus.  Well, maybe we
	can find one or two more.  Maybe we could have a dozen 
	more hearings of individuals who want to come in and 
	challenge what is the scientific consensus.  But I am 
	depressed about it and I am worried about it because time 
	is wasting for us to do something constructive about this. 
	I thank you, Mr. Chairman.
	MR. WHITFIELD.  Thank you.  Mr. Bass of New Hampshire.
	MR. BASS.  Thank you, Mr. Chairman.  I wasn't planning to 
	give an opening statement but I am kind of warming up to 
	it here.  I have been somewhat amused listening to these 
	opening statements going back and forth like a ping pong 
	ball across the table, and I just have to observe that
	we could sort of divide this debate into four different 
	categories.  We have the don't worry, be happy crowd. 
	We have the crowd that believes that the world is warming
	but because we can't agree on what to do, we might as well 
	let the good times roll while we can.  Then there is the 
	for want of a better word the political crowd that 
	maintains that this whole issue is the fault of George 
	Bush, Halliburton, the tobacco companies, tax cuts, and 
	failure to raise the minimum wage.
	Frankly, Mr. Chairman, I think these hearings have been 
	constructive.  I think they have been logical.  I think 
	Dr. Wegman's testimony's last week was dispassionate, 
	scientific, interesting.  I think it is great that we have 
	Dr. Mann here today to present another point of view.  I 
	happen to believe personally that there is a problem of 
	global warming in the world and there is a pretty good 
	possibility that that may have been caused by the excessive 
	growth of the use of hydrocarbons over the last century.  I 
	don't blame Republicans or Democrats or tobacco companies 
	or any other entity for it.  I think it is an issue that 
	we need to address, and we need to address it in a logical 
	fashion, and this is the beginning of that process.
	Now I think if I were a member of the general public I 
	would want to have a few questions answered ultimately as 
	a result of this debate.  Number one, is there a warming 
	trend going on?  Number two, is it caused by natural 
	sources or by man?  Are the oceans getting warmer?  Are 
	hurricanes getting stronger?  Is global warming the reason 
	why hurricanes might be getting stronger?  The oceans are 
	a CO2 sink.  Is global warming affecting the ability of 
	the oceans to absorb CO2 and so forth?  I think that is 
	the logical progression that a hearing such as the one 
	that we had last week and what we have today leads to--we 
	don't need to have a hearing that deals with the 
	conclusions before we build the evidence.
	So I want to thank you, Mr. Chairman, for this hearing and 
	as one who supports the concept that we need to address 
	this problem I think we are moving in the right direction. 
	I yield back.
	MR. WHITFIELD.  Thank you.  At this time I recognize 
	Mr. Inslee of Washington.
	MR. INSLEE.  This really is pathetically unworthy of 
	America, the most technologically oriented society in human 
	history, and we are here debating the equivalent of 
	gravity.  Literally while America literally burns we 
	fiddle.  This hearing makes Nero look like a responsible 
	Roman citizen.  And we have got to pull our heads out of 
	the sand in that regard.  Now the reason is--and I am not 
	depressed like Ms. Schakowsky.  I am enraged.  Since the 
	last hearing if anybody bothers to read the newspapers an 
	article comes out showing that 80 percent of the mass of 
	the glaciers in my state in North Cascades National Park, 
	one of the jewels in the crown, melted.  A study comes 
	out yesterday.  Highest heat loss, 50 deaths in 
	California, and we are sitting here fiddling around.
	Article comes out yesterday.  We have a dead zone in the 
	North Pacific where fish are dying because of change in 
	the circulation patterns in our oceans.  And we sit here 
	and fiddle around.  This would be the equivalent after 
	the Titanic of the oversight committee having a hearing 
	on how they arranged the deck chairs back in that good 
	old day.  Now why is this so ridiculous?  It is 
	ridiculous because there is total scientific consensus 
	not only in American but in the world that we are 
	responsible in part for the change in the climatic 
	systems of the globe.  I would refer to a science article 
	that studied 928 peer reviewed articles and not a single
	one of those peer review articles said anything that most
	of the folks on the Majority side want them to say.
	They all said that every single association in the world 
	that has studied this have concluded the climate is 
	changing and humans are partially responsible.  That 
	includes the American Meteorological Society, the 
	American Geo-Physical Unit, the Advancement of Science
	Association, the American Academy of Sciences, and the 
	International Panel of Climate Change.  And you know what 
	they got here?  They got nothing.  They got nothing to 
	say that those things are not true.  We are sitting here
	trying to poke holes in an 8-year old study.  You know 
	what it is like to me?  It is like at the soccer final 
	championship, and you saw the head butt by Zidane.  He 
	head butted, and everybody says he butted him.  And they 
	would argue but there was a guy up there in section 23B 
	and it didn't look like a head butt to him, and maybe 
	his eyesight was a little bad.
	The world knows what is going on here, and it is a sham. 
	I want to refer to some of the science of this.  They
	know it is a sham if you look at this graph up here.  
	Atmospheric concentrations of carbon dioxide are going 
	up unassailable.  
	Next slide, please.  

	Our contributions are going up from fossil fuel burning. 
	No question about that.  Next slide, please.
	We see the contributions, the CO2 levels globally over 
	the last 400,000 years on the top and the temperature at 
	the bottom.  What you see is that they are very, very 
	closely related.  It is an amazing relationship.  And 
	what you will see at the top if I can get a laser pointer 
	to show right up here were 370 PPM.  That is higher than 
	any time in the last 400,000 years, and what is scary is 
	it is going through the roof.  It will be double 
	preindustrial times in my lifetime and my children's 
	lifetime.
	None of this is arguable.  All of this is known.  And we 
	are going to hear discussion today that we have ice core 
	data that I will talk about that is independent of 
	Dr. Mann's research.  We have physical evidence of changes 
	of oxygen isotopes that prove what is going on, which is 
	we are changing the climate of the United States and the 
	world.  Next slide, please. 

I just want to show you, this is Antarctic ice core data.  The 
blue showing, if I can get my facts straight here, the blue 
showing temperature, the red showing CO2 variations.  The 
relationship is incredibly similar.
	And again if you look where we are going to be during my 
	lifetime and my children's lifetime, we will be right 
	here.  We will be almost off the charts, and we will be 
	double what we were in preindustrial times.  I challenge
	anyone here at this table, and I got an outstanding 
	question for all of you in this hearing, you tell me if 
	you double CO2 levels for preindustrial levels if you 
	think that is a good idea for America.  I want all of 
	you tell me if you think that is a good idea.  I think it 
	is a really bad idea.  We ought to start being more the 
	American eagle and less the ostrich and we ought to fly 
	with new technology instead of putting our head under 
	the sand on this issue and then this commerce committee 
	will start helping America.
	Next slide, please, if I can just show you one more 
	thing.
	
This is a picture of ice core.  We are sitting here talking about 
some paleoclimatic proxy data, and we are going to spend hours 
talking about it, but the fingerprints, the DNA evidence, is in 
the air in that core picture I am showing you because it is 
400,000 year old air.  We can directly measure the oxygen isotopes 
that is a direct measurement of the temperature.  We know what is 
going on and it is not a pretty picture.  And I look forward to 
the day that we start doing something about this instead of just
having these ridiculous examples and arguing gravity.  Thank you, 
Mr. Chairman.
	One more comment too before I leave just briefly.  I 
	noted Mr. Barton, my good friend, I congratulate him on 
	the baseball game this year, they whooped us again, and I 
	notice he hadn't seen this movie about climate change.  I 
	am going to invite Mr. Barton to go see this movie with 
	me.  I am going to buy him as much popcorn as he wants, 
	and I am going to agree to go to any movie he wants to go 
	to from Zorba the Greek to Lawrence of Arabia, anything 
	he wants me to see.  I think it would be good for both of 
	us.  Thanks very much.
	MR. WHITFIELD.  Thank you very much.  You can see we are a 
	very social group.
	CHAIRMAN BARTON.  If I go he is going to have to pay.
	MR. WHITFIELD.  Obviously this is a subject that people 
	feel very strongly about, and we are delighted with our 
	witnesses on the first panel today.  Now it is your turn 
	to talk, and we appreciate you being so patient while we 
	talked.  Our first witness, and I will introduce all of 
	you, Dr. Michael Mann who is the Associate Professor and 
	Director of the Earth System Science Center at Penn State 
	University, University Park, Pennsylvania; Dr. John Christy, 
	Professor and Director of Earth System Science Center, 
	University of Alabama in Huntsville; Dr. Ralph Cicerone, 
	President of the National Academy of Sciences; Mr. Stephen 
	McIntyre of Toronto, Ontario, Canada; Dr. Jay Gulledge, 
	Senior Research Fellow, Pew Center on Global Climate 
	Change; and Dr. Edward Wegman, Director, Center for 
	Computational Statistics at George Mason University.
	We welcome all of you.  As you know, this is an Oversight 
	and Investigations hearing, and we do take our testimony 
	under oath, and I would ask any of you do you have any 
	objection to testifying under oath?  Under the rules of the 
	House and rules of the committee you also are entitled to 
	legal counsel.  I am assuming that none of you have legal 
	counsel with you today, but do any of you have legal counsel 
	today?  Okay.  Then if you would stand and raise your right 
	hand, I would like to swear you in.
	[Witnesses sworn.]
	MR. WHITFIELD.  Thank you very much.  All of you are now 
	under oath.  And, Dr. Mann, we will recognize you for 
	5 minutes for your opening statement.

TESTIMONY OF DR. MICHAEL E. MANN, ASSOCIATE PROFESSOR AND DIRECTOR,
EARTH SYSTEM SCIENCE CENTER, THE PENNSYLVANIA STATE UNIVERSITY; 
DR. JOHN R. CHRISTY, PROFESSOR AND DIRECTOR, EARTH SYSTEM SCIENCE 
CENTER, NSSTC, UNIVERSITY OF ALABAMA IN HUNTSVILLE; DR. RALPH J. 
CICERONE, PRESIDENT, NATIONAL ACADEMY OF SCIENCES; MR. STEPHEN 
MCINTYRE, TORONTO, ONTARIO, CANADA; DR. JAY GULLEDGE, SENIOR 
RESEARCH FELLOW, PEW CENTER ON GLOBAL CLIMATE CHANGE; AND DR. 
EDWARD J. WEGMAN, DIRECTOR, CENTER FOR COMPUTATIONAL STATISTICS, 
GEORGE MASON UNIVERSITY

DR. MANN.  Mr. Chairman, members of the committee, thank you for 
inviting me here to appear before you today.  I became a climate 
scientist because the Earth's climate is a fascinating and complex 
system and understanding how it works is so important.  Part of my 
research has involved examining preindustrial climate history in 
order to learn about the natural variations in the Earth's climate.  
My research in this field, not just the initial work that my 
colleagues and I published in the late 1990s, but my recent research 
as well suggests late 20th Century Northern Hemisphere average 
temperatures are unprecedented over at least the past 1,000 years.
	Of course, we have accurate thermometer measurements only 
	back about 100 years, and so we estimate climate prior to 
	that period from indirect sources called climate proxies 
	such as tree rings, corals, and ice cores.  This work 
	involves many uncertainties and there are numerous judgment 
	calls that must be made.  For that reason we are rarely 
	categorical in the conclusions that we reach.  What is 
	important, however, is that the scientific community has 
	reached consensus that recent northern hemispheric average 
	warmth appears to be unprecedented over at least the past 
	1,000 years, and that this warmth can only be explained by 
	anthropogenic or human influences on the climate.
	This conclusion is not based on single studies or isolated 
	research but is confirmed by many studies using different 
	sets of data and independent statistical methods and indeed 
	this conclusion was just echoed weeks ago by a report of 
	the National Academy of Sciences, the most prestigious 
	nonpartisan scientific body in the Nation.  So where does 
	my research fit into this?  Taken as a whole my own 
	research is in accord with the scientific mainstream 
	reflected in the National Academy report and elsewhere that 
	there has been unprecedented warming in the Northern 
	Hemisphere over the past 100 years.
	Exhibit A, if you can take a look at Exhibit A there, that 
	shows that this conclusion is common to a number of similar 
	studies including two I was involved with.  This committee 
	is not looking at my work on the whole or on the larger 
	body of science on this issue.  It is instead focusing on 
	the first study of this type my colleagues and I published 
	and undertook in 1996 while I was still a graduate student.  
	While there were previous reconstructions based on proxy 
	data our study was the first to estimate global patterns 
	of past temperature change and the first to estimate 
	uncertainties.  Our initial study published in the journal, 
	Nature, in 1998 was followed by an additional study in the 
	journal, Geophysical Research Letters, in 1999.  The main 
	conclusion of the 1998 study was that there had been 
	unprecedented warming in the Northern Hemisphere in recent 
	decades.  The 1999 study reinforced this conclusion but 
	also reassessed and expanded the uncertainties and added 
	he tentative conclusion that it was likely that the 1990s 
	were the warmest decade over that thousand year time period 
	and that 1998 was the warmest year.
	The 1999 study included a graphic depiction of the 
	temperature history over the last millennium, which 
	demonstrated an unprecedented rise during the 20th Century. 
	Some have dubbed this graphic the hockey stick.  If the 
	question this committee seeks to answer is whether knowing
	what I know today, a decade after starting the original 
	study, my colleagues and I would conduct it in exactly the
	same way, the answer is plainly no.  The field of 
	paleoclimate reconstruction has evolved tremendously over
	the past decade.
	Important new proxy data have been developed. 
	Reconstructions have been compared with independent 
	estimates from climate model simulations and confirmed by 
	those simulations.  Statistical methods for reconstructing 
	climate from proxy data have been refined and rigorously 
	tested, and I have been actively working in each of these 
	areas.  This is important because all the focus of criticism
	on our work in the late 1990s has been on the statistical 
	conventions we used.  My co-authors and I have not used those 
	conventions in our later work.
	The critique goes only to our first reconstruction effort.  It
	does not apply to our more recent studies all of which 
	indicate the same basic hockey stick result.  Exhibit B 
	demonstrates this point.  The green reconstruction does not 
	use principal component analysis at all so the statistical 
	conventions being discussed here have no relevance, and it is 
	the same basic reconstruction, if you will, essentially the 
	same "hockey stick."  Now our critics do not confront the 
	fact that our basic conclusion is not an isolated or 
	aberrational finding reached only in one study.  Every 
	climate scientist who has performed a detailed reconstruction 
	of the climate of the past 1,000 years using different proxy 
	data and different statistical methods has come up with the 
	same basic hockey stick pattern, that is to say a 
	reconstruction that agrees with our original reconstruction 
	within its estimates uncertainties.
	My critics also fail to recognize that even if their 
	criticisms are accepted it has no bearing on the outcome.  
	Dr. Wegman's report argues that the hockey stick pattern 
	derives from the statistical conventions used in our 1998 
	and 1999 studies.  However, using alternative statistical 
	conventions yields the same hockey stick pattern.  The 
	hockey stick pattern is intrinsic to the data.  That was 
	the conclusion of the National Academy.  Page 116 of the 
	National Academy report says the statistical convention my 
	colleagues and I used "does not appear to unduly influence
	reconstructions of hemispheric mean temperature; 
	reconstructions performed without using principal component
	analysis are qualitatively similar to the original curves 
	presented by Mann et al."
	This was also the conclusion reached by Dr. Hans von Storch 
	who testified here last week, and by four independent teams 
	of scientists who published peer reviewed articles 
	considering and rejecting the conclusion that the statistical
	methods used in our early studies were responsible for the 
	hockey stick result.  Finally, my critics ignore the fact 
	that other scientists have repeated original results using 
	the centered PCA analysis that Dr. Wegman favors and have
	concluded that the result is basically the same as we 
	originally reported.  This is summarized in Exhibit C.
	So even if one accepts as valid the criticisms about the 
	statistical conventions used in our early work our results are 
	essentially unaffected.  As you can see, the two curves are 
	barely distinguishable within the width of the lines that are 
	shown.  And as I have said before our key conclusion that 
	recent hemispheric warmth appears unprecedented over at least 
	the past millennium has been confirmed by every study that 
	has examined the same question.
	Finally, it is worth expressing again that paleoclimate 
	reconstructions represent just one of many independent lines 
	of evidence that support the conclusion that human activity 
	is already having a substantial impact on global climate.  
	I appreciate this opportunity to answer the committee's 
	questions.  I am sorry I could not be here last week but 
	as I had explained to committee staff, I had to take care 
	of my infant daughter while my wife was attending a 
	conference.
	[The prepared statement of Dr. Michael E. Mann follows:]


PREPARED STATEMENT OF DR. MICHAEL E. MANN, ASSOCIATE PROFESSOR AND 
DIRECTOR, EARTH SYSTEM SCIENCE CENTER, THE PENNSYLVANIA STATE 
UNIVERSITY




	MR. WHITFIELD.  Dr. Mann, thank you.  You have heard all 
	the bells going off.  We do have a series of four votes on 
	the floor but before we go, Dr. Christy, I am going to ask
	you to give your opening statement.  Then we will recess for
	probably about 30 minutes and we will come back and take the 
	rest of the testimony.
DR. CHRISTY.  Thank you.  Chairman Whitfield, Ranking Member Stupak, 
and committee members, I am John Christy, Director of the Earth System 
Science Center at the University of Alabama in Huntsville, and the 
Alabama state climatologist.  I served as a lead author of IPCC 2002 
chapter on observations with Dr. Mann, and as panelist on the NAS 
report on temperature reconstructions.  As the lead author of the 
IPCC, I helped craft the now infamous statement about the 1990s and 
1998 being the warmest decade and year.
	Our confidence was described as likely rather than very 
	likely or virtually certain.  In other words, we chose a 
	relatively low level of confidence because of the following 
	concerns known at that time.  First, that the hockey stick 
	was new and had not had time for independent analysis for 
	confirmation or revision.  Two, a key factor or a key anchor
	for that early part of the record was a western tree ring 
	series that explained only about 5 percent of the overall 
	variability.  And, three, that the unavoidable constraints 
	on the length of the calibration and validation periods 
	really prevented confident knowledge of the relative warmth 
	of different centuries.
	A more disappointing aspect of the IPCC regarding temperatures 
	over the last millennium was that some important work was not 
	included, specifically the work of Dahl-Jensen et al., 1998, 
	which I recommended for inclusion many times, was completely 
	missing from this section.  These borehole temperatures from
	Greenland represented probably the most reliable regional 
	temperatures over the last millennium.  Thus, in at least 
	one location we had high confidence that it was warmer 1,000 
	years ago, and though Greenland's temperature may not be 
	tightly connected to hemispheric averages, Greenland is 
	important for sea level averages.  If Greenland were warmer
	in the relatively recent past were its edges also melting 
	as they appear to be now under cooler conditions?  I believe 
	the IPCC missed an opportunity to demonstrate climate 
	complexity by excluding this information in 2001.  
Dr. Roy Spencer and I created the first satellite-based data set 
temperature back in 1990.  We are now working on improvements to the 
8th revision brought about by the divergence of the two most recent 
satellites.
	When asked by others, we provided sections of our code and 
	relevant data files.  By sharing this information, we opened 
	ourselves up to exposure or a possible problem which we had
	somehow missed, and frankly this was not personally easy.  On
	the other hand, if there was a mistake we wanted it fixed.  
	Not knowing the outcome of the work done by scientists at
	Remote Sensing Systems they asked if they could publish what
	we had sent them.  In my formal scientific response, I wrote,
	"Oh, what the heck.  I think it would be fine to use and 
	critique, that is sort of what science is all about."
	And so it was that in August 2005 RSS published a clear 
	example of an artifact which created errors in the tropics in 
	our data.  In Science magazine the following November we 
	published the information about our now-corrected 
	temperatures and expressed our gratitude to RSS for 
	discovering our error.  While a bit painful, this process as 
	recommended in the National Academy's report, resulted in 
	progress and better scientific information.
	Finally, greenhouse gas concentrations are increasing, and 
	therefore the radiation budget of the atmosphere will be 
	altered.  In response, the surface temperatures will or 
	should rise.  Our observational work, however, has not been 
	able to show clear support for the manner or magnitude of 
	this response as depicted by current climate models.  For 
	policy makers this is important.  For example, we cannot 
	reliably reproduce or predict the climate for large regions 
	within the United States.  It would be a far more difficult 
	task to reliably predict the effects of a policy that reduce
	greenhouse gas emissions.
	Simply put, we cannot say with any confidence to you or to 
	the American taxpayer that by adopting policy X we will cause 
	an impact Y on the weather of the climate system.  
What I really find disturbing today is the demonization of energy and 
its most common byproduct, carbon dioxide, CO2.  I cannot call CO2 a
pollutant when it is a source of life on the planet.  CO2 is plant 
food.  But, as importantly, the extra CO2 we have put in the air 
represents astounding improvements in the health, longevity, and 
quality of human life.  I suspect half of us in this hearing room 
would not be here but for the benefits wrought by affordable energy. 
Energy use is not evil.
	I believe my experience in Africa is important in this whole 
	discussion of energy and climate.  In the 1970s I taught 
	science and math as a missionary teacher, and I saw the 
	energy system there.  The energy source was wood chopped 
	from the forest.  The energy transmission system was the
	backs of women and girls hauling wood an average of three 
	miles each day.  The energy use system was burning the 
	wood in an open fire indoors for heat and light.  The 
	consequence of that energy system was deforestation and 
	habitat loss while for people it was poor respiratory 
	and eye health.  The U.N. estimates 1.6 million women 
	and children die each year from the effects of this 
	indoor smoke.
	Energy demand will grow, as it should, to allow these 
	people to experience the advances in health and quality 
	of life that we enjoy.  They are far more vulnerable to 
	the impacts of poverty, water pollution, and political 
	strife than whatever the climate does.  I simply close 
	with a plea, please remember the needs and aspirations 
	of the poorest among us when energy policy is made.  
	Thank you very much.
	[The prepared statement of Dr. John R. Christy follows:]


PREPARED STATEMENT OF DR. JOHN R. CHRISTY, PROFESSOR AND DIRECTOR, 
EARTH SYSTEM SCIENCE CENTER, NSSTC, UNIVERSITY OF ALABAMA IN 
HUNTSVILLE





	MR. WHITFIELD.  Dr. Christy, thank you.  We are going to 
	go vote.  It is now 15 after 3:00 so we will reconvene 
	about 15 till 4:00.  Down in the basement there is a 
	little snack center and if you go out the main first floor 
	of the Rayburn Building and walk over to Longworth there 
	is a wonderful ice cream shop so whatever you decide to do.
	[Recess.]
	MR. WHITFIELD.  The hearing will reconvene, and we apologize 
	for the delay.  We are about 35 minutes later than we said. 
	But, Dr. Cicerone, you are recognized for your 5-minute 
	opening statement.
DR. CICERONE.  Thank you, Chairman Whitfield and members of the
committee.  My name is Ralph Cicerone.  I am President of the National 
Academy of Sciences and Chairman of the National Research Council.  
Prior to this year, I was Chancellor of the University of California at
Irvine where I was Aldrich professor in Earth System Science and also
professor of chemistry.  This afternoon I will summarize the state of
scientific understanding on climate change very briefly, based on 
findings and recommendations in NAS and NRC reports and in some recent 
refereed publications.  Our reports, quite often written with the 
National Academy of Engineering and the Institute of Medicine, go 
through a peer review process and although we are not part of the 
Government, we were chartered by Congress and President Lincoln to 
provide advice on matters of science and technology.
	I would like to first start with how is it that humans can 
	influence the climate of an entire planet.  The strongest 
	answer is the greenhouse effect which is a natural
	phenomenon.  Without the natural greenhouse effect, the 
	Earth would be much colder than it is right now.  We can
	test that prediction by looking at Mars and Venus, for 
	example.  Now humans are amplifying the natural greenhouse 
	effect.  Just to give you one major, the extra energy 
	trapped near the earth's surface by a variety of greenhouse 
	gases is about 2-1/2 watts per square meter now, which is
	about 100 times larger than all the energy usage by humans 
	worldwide on the entire planet from all sources, fossil
	fuels, nuclear wind, hypothermal, you name it.  It is a big 
	number.  This is what gives humans leverage to influence an
	entire planetary climate.
	There is no doubt that the Earth is warming.  Weather station
	records and ship-based observations show that the global 
	average surface temperature in the air has increased by about 
	1.2 degrees Fahrenheit since the beginning of the last 
	century, more than half of the increase since 1975.  Scientists
	have also measured upward temperature trends in the lower 
	atmosphere and in the upper oceans, and this continuing warming 
	has been accompanied by worldwide changes and many other 
	indicators, such as decreases in Arctic sea ice thickness and 
	extent, and shifts in ecosystems.
	What is the primary evidence for this widely accepted view 
	that global warming is occurring, that human beings are 
	responsible at least in part for the warming and that the 
	Earth's climate will continue to change during this current 
	century.  There are many lines of evidence.  Let me summarize 
	them briefly.  First, measurements show large increases in 
	carbon dioxide and other greenhouse gases, such as methane and 
	nitrous oxide, beginning in the middle of the 19th Century.  
	These increases in greenhouse gases are due to human 
	activities such as burning fossil fuel for energy, 
	agricultural and industrial processes, and so forth.  The 
	concentration of carbon dioxide is now at its highest level 
	shown by actual measurements in the last 650,000 years.  The 
	record has been extended back that far now.
	Second, we understand how carbon dioxide and other greenhouse 
	gases physically affect global temperature.  Rigorous 
	radioactive transfer calculations of the temperature changes 
	due to increasing greenhouse gas concentrations, together 
	with reasonable assumptions about climate feedbacks provide a 
	physically based mathematically sound explanation for the 
	observed warming.
	Third, state-of-the-art mathematical climate models are able 
	to reproduce the warming of the past century, but only if 
	human-caused greenhouse gases are included.  Fourth, and I
	did not have this in my written testimony, but simulations 
	of the stratospheric penetrating volcano, Mount Penatubo, in 
	mid-June 1991 were able to show the exact timing of the cooling 
	that took place afterwards based on the sulphate particles and 
	got the magnitude of the cooling almost right.  And these were
	primitive models at the time.  Models have improved a great
	deal since.
	Fifth, analysis of high-quality, precise measurements of the 
	sun's total brightness over the past 25 years show little, if
	any, change in the long-term average of solar output over this 
	time period.  Thus, changes in the sun, the best explanation 
	for a natural explanation cannot explain the warming over the
	past 25 years.  
Six, the oceans have warmed in recent decades and the stratosphere 
has cooled.  Land masses north of the tropical region in the Northern 
Hemisphere have warmed even more than the oceans.  All of these large
scale changes, their sizes and patterns are consistent with the 
predicted geographical and temporal pattern of greenhouse surface 
warming.
	Seventh, ice covered regions of the Earth have experienced 
	significant melting.  For example, the average annual sea
	ice extent of the Artic has decreased by about 8 percent
	or nearly a million square kilometers over the past 30 
	years.  Sea ice thickness measured, for example, by the 
	United States Navy has decreased over the period.  
	Measurements from Earth orbiting satellites from synthetic 
	aperture radars and from Earth's gravity sensors over the 
	last few years have shown that both Greenland and West 
	Antarctic ice sheets are losing ice.
	Eighth, several publications in the last 2 years show that 
	hurricane intensities have increased in some parts of the
	world in lock step with sea surface temperatures.  
While we are quite certain that the Earth's surface has heated up 
during the last 30 years, and that it is hotter now than at any 
time during the last 400 years, predicting what will happen to 
important climate variables besides temperature is more difficult.
	As we stated in our 2001 report climate change simulations 
	yield a globally averaged surface temperature increase by 
	the end of this century of maybe 2-1/2 to 10 degrees 
	Fahrenheit.  As I said, temperature is easier to predict 
	than other changes such as rainfall, storm patterns, and 
	ecosystems, and the prediction of extreme events, which is 
	what probably humans and other biological creatures respond
	to the most are very difficult.
	While these future climate changes and their impacts are 
	inherently uncertain, they are far from unknown.  We can 
	paint useful broad brush pictures now of how global warming
	may affect certain regions of the world.  For example, these 
	mathematical models generally project more warming in 
	continental regions than over the oceans and in polar regions
	rather than near the equator.  Precipitation is expected to
	increase in the tropics, decrease in the subtropics, and 
	increase in the midlatitudes.  Rainfall is expected to 
	increase in monsoon regimes.  We can give a lot of broad brush 
	predictions like that that are difficult to prove, but that is 
	the state of the science now.
	Even if no further increases in the atmospheric concentrations 
	of greenhouse gases occur, which would be a difficult to 
	achieve scenario, we are very likely to experience additional 
	warming of about 7/10ths of a degree Fahrenheit in the coming 
	decades.  In colder climates such warming could bring less 
	severe winters and longer growing seasons if soil moisture is 
	adequate.  Several studies, quite credible, have projected 
	that summertime ice in the Arctic could disappear in this 
	century, the end of the century.
	The combined effects of ice melting and sea water expansion 
	from ocean warming will likely cause the global average sea 
	level to rise by anywhere between 1/10th and 9/10ths of a 
	meter in this century.  So coastal communities will experience 
	increased flooding due to seal level rise and are likely to
	experience more severe storms and storm surges.  And of
	course increased acidification of the surface ocean due to
	the added carbon dioxide from the atmosphere is occurring. 
	It will continue and it will harm marine organisms such as 
	corals and some plankton species.
	In summary, there are multiple lines of evidence supporting 
	the reality of and human roles in global climate change.  I 
	think I will stop there to be as brief as possible.  With 
	your permission, Mr. Chairman, I have submitted two 
	appendices.
	[The prepared statement of Dr. Ralph J. Cicerone 
	follows:]


PREPARED STATEMENT OF DR. RALPH J. CICERONE, PRESIDENT, NATIONAL 
ACADEMY OF SCIENCES



	MR. WHITFIELD.  Well, thank you so much, and your entire 
	statement is part of the record, and we appreciate your 
	being here.  Mr. McIntyre, you are recognized for 
	5 minutes.

MR. MCINTYRE.  Thank you. Good afternoon, Mr. Chairman, and 
members of the committee.  My name is Stephen McIntyre.  I 
appreciate the invitation to appear before you once again.  I will 
recap my testimony from last week, referring to the NAS and Wegman 
reports.  The Wegman report drew attention to a remarkable lack of 
independence in data used in supposedly independent studies.  Some
proxies are used in nearly every such study.  This raises the 
spectre that problems in one proxy can spill over to multiple 
reconstructions.
	One such problem has already been identified.  The NAS panel
	agreed that strip bark bristlecones should be avoided in 
	temperature reconstructions but they did not assess the 
	potential impact of this conclusion.  Last week I showed that
	this recommendation reversed the estimates of medieval modern 
	levels in the Crowley and Lowery reconstruction.  Here we 
	show the impact of this on the Mann study, where the 
	conclusion of 20th Century uniqueness does not withstand 
	removing the bristlecones.  Every reconstruction using 
	bristlecones will have to be reconsidered in the light of 
	thee NAS recommendation.
	By coincidence the key bristlecone sites are located in an
	area recently studied by Dr. Christy where he recompiled 
	high altitude temperature data.  There is actually a slight 
	negative correlation between Christy's temperature data and 
	Mann's key principal component series.  You can readily see 
	why the NAS panel said that bristlecones should be avoided
	as a temperature proxy.  Further grounds for concern about 
	the use of this data comes from fossil trees located well 
	above modern tree lines in this area, dated to the Medieval 
	Warm Period.  Recent ecological niche studies have concluded 
	that the annual minimum temperatures in this area were 3.2 
	degrees Centigrade warmer, that is 6 degrees Fahrenheit 
	warmer, than at present.
	Dr. Mann likes to say that any problems do not arise 
	simply, and I emphasize simply, from the flawed PC method. 
	If the proxies were ideal, such as the synthetic data 
	studied by von Storch and Zorita, the bad method may not 
	make a difference.  But in such circumstances a simple 
	average would also have a hockey stick shape which were not
	observed in the simple average of the Mann proxies.  The
	real problem, and the one observed by Wegman, is that the 
	PC method as applied to low quality data caused a minor 
	pattern, in this case bristlecones, to be exaggerated as
	a dominant pattern in worldwide climate.
	Notably, Dr. Mann's testimony does not mention 
	bristlecones but in his data, the hockey stick shape is 
	dependent on them.  The graph here shows in red the 
	contribution to his reconstruction for bristlecones.  The 
	other colors show the contribution from other classes of 
	proxies.  As you can see, there is very little information
	from the other proxies.
	Dr. Mann has also said that he can get a hockey stick 
	shape in another way.  There are many ways of processing 
	Mann'a data set.  Some result in hockey stick shape 
	series, some do not.  Burger and Cubasch in 2005 showed a 
	bewildering variety of outcomes based on a slight 
	variation in methodology.  Sometimes you are told that 
	scientists have moved on, and that the criticized methods
	are no longer used.  This is not the case.  All of 
	Dr. Mann's more recent work used his disputed PC1.  Mann's 
	PC1 was used in the prominent article, Osborne and Briffa 
	2006, and even occurs illustrated as a temperature proxy 
	in one of the NAS illustrations.
	An important control on any statistical study is reporting
	of adverse results.  The verification r2 statistic is 
	commonly used in paleoclimate studies and was said in the 
	original article to have been considered.  However, early 
	periods of the reconstruction failed the significance test,
	a fact which was never reported.  At the NAS press 
	conference, Dr. Bloomfield said that he found nothing 
	unusual about MBH reporting.  If paleoclimate research 
	practices do not require scientists to disclose results 
	adverse to their claims, then this reduces the ability of 
	policy makers to rely on these studies.
	Last week I pointed out many problems with data and code 
	access.  Much relevant Mann data did not become available 
	until 2004, 6 years after the original study, and then
	only after a formal complaint to Nature.  Mann's archiving
	practices are by no means the worse in the community.  
	Much of Lonnie Thompson's data remains unarchived 20 years 
	after it was collected.  The efforts of your committee led 
	to Dr. Mann disclosing a considerable amount of source
	code.  Unfortunately, the source code does not operate 
	with the data as archived and it does not include code for
	important steps such as the calculation of confidence
	intervals or PC retention rules.
	Wahl and Ammann have been described as independent studies
	but they are co-authors and collaborators with Dr. Mann 
	and their efforts, whatever their merit, can hardly be 
	described as independent.  To the credit of Wahl and 
	Ammann, they have archived their code for their study
	following a practice that we followed.  Their code 
	reconciles to ours and any differences between the studies 
	do not arise from differing arithmetic.
	The interest of this committee in reconstruction seems to
	have been prompted in part when Dr. Mann was quoted by 
	the Wall Street Journal as saying that he would "not be 
	intimidated into disclosing his algorithm."  Such 
	attitudes are inconsistent with the requirement of policy
	makers if they are to rely on such studies.  If you are 
	to rely on paleoclimate studies you should be concerned 
	about disclosure, data access, and replication because, 
	first, peer review at journals is very limited and does 
	not constitute sufficient due diligence for policy 
	reliance.
	Second, IPCC does not carry out independent testing or 
	verification.  Third, to enable and facilitate independent
	testing, paleoclimate research needs to achieve 
	dramatically improved standards for archiving data and 
	code.  Fourth, because much of the work is funded by the 
	U.S. Federal government, improved administrative practices
	by NSF and DOE could make a direct and immediate impact
	and improvement.  Thank you.
	[The prepared statement of Stephen McIntyre follows:]

PREPARED STATEMENT OF STEPHEN MCINTYRE, TORONTO, ONTARIO, CANADA

SUMMARY

1. little reliance can be placed on the original MBH reconstruction, 
various efforts to salvage it or similar multiproxy studies, even 
ones which do not use Mann's principal components methodology;
2. peer review as practiced by academic journals is insufficient 
due diligence for policy reliance. IPCC reports are only a literature
review rather than independent due diligence.
3. to enable and facilitate independent testing, paleoclimate research
practices need to achieve dramatically improved standards for
archiving data and code. 
4. administrative policies governing work directly funded by the 
U.S. government can make a direct and immediate difference.

Good morning, Mr Chairman and members of the Committee. 
My name is Stephen McIntyre. I appreciate the invitation to appear
before you once again. I will recapitulate my testimony from last
week, making further reference to the NAS and Wegman reports.
The Wegman report drew attention to a remarkable lack of 
independence in the proxies used in supposedly "independent" 
studies. Some sites are used in nearly every study. This 
raises the spectre that problems with one proxy can spill over 
to multiple studies. One such situation has already been 
identified. The NAS panel agreed that strip-bark bristlecones
should be "avoided in temperature reconstructions".  Last week,
we showed that this reversed medieval-modern levels in the 
Crowley and Lowery 2000 reconstruction. Figure 1 below shows 
the impact on MBH, where conclusions of 20th century uniqueness 
do not withstand removing the bristlecones. Wegman showed that 
bristlecones were used in multiple studies and each one will 
have to be reconsidered in light of the NAS recommendation.

Figure 1. MBH99 reconstruction and estimate of MBH99-type 
reconstruction without bristlecones. 20-year gaussian smooth.

By coincidence, the key bristlecone and foxtail proxies that 
establish the pattern in Mann's critical PC series are located 
in almost the exact area studied by Christy, as shown in the 
location map on the left. As you see, there is little correlation
on either a smoothed or unsmoothed basis  - actually a slight 
negative correlation - between  temperature and Mann's PC1. You
can readily see why the NAS panel said that this data should be
avoided as a temperature proxy.



Figure 2. Left - location of foxtail and bristlecone sites in 
the Sierra Nevada and White Mountains. Right - Black - annual 
mean of maximum and minimum temperatures (data, Christy, pers. 
comm.); red - MBH98 NOAMER PC1.

Further grounds for concern about using Mann's PC1 as a
temperature proxy comes from the evidence of fossil trees well 
above modern tree lines, dated to the Medieval Warm Period. 
Millar et al. 2006 concluded that annual minimum temperatures in
this area were then significantly warmer (+3.2 �C) than at
present.   

Figure 3. A dead trunk above current treeline from a foxtail pine
that lived about 1000 years ago near Bighorn Plateau in Sequoia
National Park.

Dr Mann likes to say that any problems do not arise simply from 
the flawed PC method. However, it's not true that the flawed PC 
method has nothing to do with the problems. A simple average of
Mann's proxies does not yield a hockey stick shaped series, as 
shown in Figure 4 below. If you have proxies of ideal quality, 
even a bad PC method can yield meaningful results - which is 
what von Storch and Zorita observed, using idealized data 
generated in a climate model. However, the problem is that 
Mann's PC method was applied to low-quality data, where the 
flawed method caused a minor pattern in bristlecones to be 
exaggerated as a "dominant pattern" in worldwide climate. 

Figure 4. Left: Top - Average of all 415 MBH proxies; bottom - 
MBH reconstruction. Both in standard deviation units.

In the MBH data set, the hockey stick shape is dependent on the
bristlecones. All the statistical salvage jobs Dr. Mann cites 
are variations on schemes to load the final weight on the very 
data the NAS panel said should not be used.

Figure 5.  Top - Contribution (deg C) of proxy groups (proxy 
type x continent e.g. Asian tree rings; South American ice 
cores) to the MBH reconstruction, with bristlecones and foxtails
in red. Bottom - Same series in standard deviation units. The
bristlecone contribution closely matches the final MBH 
reconstruction.

There are many ways of processing the MBH data - some result in 
hockey-stick shaped series; some do not. B�rger and Cubasch 2005 
showed a bewildering variety of outcomes based on slight 
variations in MBH methodology. 


Figure 6: Different MBH-type results from slight methodological 
differences from Burger and Cubasch [2005] SI Figure 1.

Sometimes you're told that scientists have "moved on" and that 
the methods criticized by Wegman and the NAS panel are no 
longer used. However, this is not the case. Rutherford et al.,
coauthored by Dr Mann and published in late 2005, used the 
identical PC method as the 1998 paper.
Although 415 individual proxy series were used, data reduction
by using leading PCs of tree-ring networks results in a 
smaller set of 112 indicators in the multiproxy-PC network 
available back to 1820 (Fig. 1a), with a decreasing number of
indicators available progressively further back in time. 
Twenty-two of the indicators (representing 95 individual proxy
series) extend back to at least A.D. 1400.

Mann's PC1 was also used in Osborn and Briffa 2006. And 
despite criticisms of the PC methodology by the NAS panel, 
they themselves used it, perhaps inadvertently, in one of 
their illustrations as a temperature proxy - see the top panel 
of Figure 6 of the NAS report. 
An important control on any statistical study is reporting of 
adverse results. The verification r2 statistic is commonly used 
in paleoclimate studies and was said to have been considered in 
MBH98. However, its early periods had insignificant values of 
this statistic, a fact that was never reported. At the NAS
press conference, Dr Bloomfield said that he found nothing 
unusual about reporting of results in MBH. If paleoclimate 
research practices do not require scientists to disclose 
results adverse to their claims, then this reduces the ability 
of policy-makers to rely on these studies. 


Source: Wahl and Ammann 2006.

Last week, we pointed out many problems with data and code 
access in paleoclimate. In the MBH case, much relevant data 
did not become available until the 2004 corrigendum, 6 years 
after the original study, and only then after a formal
complaint to Nature. The efforts of your committee led to
Dr Mann disclosing a considerable amount of source code. 
Unfortunately, as Dr Wegman reported to you, the source code
does not work with any data sets presently archived and is 
inoperable. It also does not include code for some important 
steps, such as MBH99 confidence intervals or PC retention 
rules, which neither ourselves nor Wahl and Ammann have been 
able to replicate. Since Wahl and Ammann are recent coauthors 
and collaborators with Mann, their efforts hardly can be 
described as "independent" replication.
Dr Mann and his associates are by no means the worst in the 
paleoclimate field in archiving data. It is undoubtedly
frustrating for Dr Mann to be the center of attention when 
many of his colleagues are much worse. For example, despite 
over 2 years of effort, I have been unsuccessful in learning 
what sites were used in one of three paleoclimate studies 
illustrated in the IPCC Third Assessment Report (Briffa et 
al 2001). These sites were recently been used by Mann and 
coauthors, who have also failed to even disclose the location
of the sites.
The reason why data access and replication should be of 
concern to you is that: 
(1) peer review at journals is very limited and does not 
constitute sufficient due diligence for policy reliance; 
(2) IPCC does not carry out due diligence on articles.  
(3) In order to properly assess a study, it needs to be 
replicated. Placing obstacles in the way of access to data 
and code makes this either impossible or simply impractical for 
people with less than infinite patience. 
(4) Because much of the work is funded by the U.S. federal 
government, there are direct and practical steps that can be 
taken with NSF and DOE that would have an immediate impact 
in improving the quality of due diligence in this field.

	MR. WHITFIELD.  Thank you.  Dr. Gulledge, you are recognized 
	for 5 minutes.
DR. GULLEDGE.  Thank you, Mr. Chairman, Ranking Member, and members 
of the committee.  I am Jay Gulledge.  I am a Senior Research Fellow
with the Pew Center on Global Climate Change, and an Adjunct 
Assistant Professor at the University of Louisville, where I
conduct research on the carbon cycling.  I just want to try to 
provide a little bit of context here today.  I am not a 
paleoclimatologist or a statistician, but I am a professional 
scientist observing--I am a generalistic climate change scientist 
through my duties at the Pew Center on Global Climate Change.
	[Slide]
	Next slide, please.  I just want to reiterate, now 
	Dr. Cicerone mentioned most of these things, but this is not
	about the fundamentals of climate change science and the 
	hockey stick reconstruction is not a foundation.  Chain 
	activities are increasing greenhouse gases.  The Earth is 
	warming.  These are unequivocal facts.  The warming over the 
	past 5 decades has been attributed through sound science to
	human activities associated with greenhouse gases.  The 
	effects of warming are being seen today all over the globe, 
	and this warming is going to continue for a long time even if
	we stabilize greenhouse gases in the atmosphere today.  Next
	slide.
	[Slide]
	Now the main points I want to make today, the so-called 
	hockey stick controversy is not a scientific construct.  The
	controversy is in science and that is because debate is
	normal in science and people re-examine each other's methods 
	and so forth.  This is not controversial.  It is just not 
	controversial in science.  The criticisms of the hockey stick
	scientifically speaking do not undermine the climate, the 
	science of climate change.  It is just not central to our 
	understanding of it.
	The results of the hockey stick actually represent a 
	gradual development in the understanding in the paleoclimate
	community of past climate, not any kind of step change in 
	the understanding.  This is readily demonstrated from the 
	scientific literature over the past 20 years.  And in my
	opinion climate change assessments are working well under
	the supervision of climatologists.
	[Slide]
	The next slide, I just want to point out the bottom quote 
	here from the NAS report that says the surface temperature 
	reconstructions I have included such as the hockey stick 
	are consistent with other evidence of global climate change 
	and can be considered, and this is the operational phrase 
	here, my point, as additional supporting evidence.  It is
	not central to climate science.  Next slide.
	[Slide]
	This is the hockey stick as presented in the 2001 IPCC.  It 
	is a reconstruction of the average northern hemispheric
	temperature over the last thousand years.  Next slide.
	[Slide]
	And the main conclusions as you have heard over and over 
	again the 20th Century is the warmest in the past thousand 
	years.  The 1990s were the warmest decade, and even 1998 
	being the warmest year as represented by the blade of the 
	hockey stick here.  Next slide.
	[Slide]
	Now the criticisms that have been discussed in this hearing 
	as leveled by McIntyre and McKitrick have to do with 
	statistical methodology and whether they were applied properly,
	inappropriate use of data, and a general complaint that this 
	has resulted in an incorrect elimination of the Medieval Warm
	Period which would show where the red oval is here.  Next 
	slide.
	[Slide]
	Now as a result of these criticisms this committee has asked
	Mr. Wegman to produce a report along with his colleagues to
	examine these criticisms.  And the primary objective of this 
	report, as quoted from the report, is to "reproduce the 
	results of McIntyre-McKitrick nor to determine whether the 
	criticisms were valid and have merit."  I put in red the 
	last phrase.  I think this has not been accomplished by the 
	Wegman report at all, and I will illustrate why.  Next
	slide.
	[Slide]
	It just seems reasonable that you got to look at what has 
	happened since this because you are trying to find out the 
	reliability of the science here.  Second, Mann's claims 
	that McIntyre and McKitrick didn't apply his method 
	correctly are not addressed in the Wegman report at all but
	they certainly are germane.  If those criticisms are being 
	used to question the work then that has to be examined.  
	Corroborating evidence wasn't looked at.  That was the 
	strength of the NAS report, I would say.  And finally in red
	here a very important report with regard to the questions of
	this committee was really overlooked by this report showing 
	up only in a footnote on a later page or on a middle page.
	But this thing, this study by Wahl and Ammann from the 
	National Center of Atmospheric Research, actually looked at 
	all the main criticisms of the McIntyre-McKitrick papers, 
	and whether they are correct or not, this should have been 
	examined by any investigation wanting to look into the 
	merits of the McIntyre-McKitrick criticisms.  Next slide.
	[Slide]
	Now what they are showing is that they are able to reproduce 
	extremely closely the original Mann 1998 hockey stick.  Here
	in gray is the original Mann result, and if you can't see 
	it it is because it is under the red line, which is their 
	emulation.  They did this writing their own code in the R
	programming language, and they made a very faithful 
	reproduction. Next.
	[Slide]
	Now using their reproduction they then tested whether or not
	the McIntyre-McKitrick criticisms had an effect on the 
	result of the reconstruction.  In this figure they have 
	corrected for the de-centering problem prior to the PC 
	analysis, and also they removed the gaspe tree ring series 
	that was questioned by McIntyre and McKitrick.  And the
	result is the only change that occurred that has any 
	significance is in the 14th Century.  You see the red line 
	is their emulation of Mann and the blue, which is sticking 
	up a little bit on the very left hand of the graph, is 
	the effect of the corrections.
	Now this really just doesn't change--and these green and 
	magenta are the 95 percent confidence intervals.  This 
	really just doesn't change the picture of the 20th Century
	being unique.  Now it does leave the impression that 
	perhaps there is a trajectory of warming as you move back 
	in time.  Maybe that continues to go up and the Medieval
	Warm Period, which isn't even shown here, maybe got warm.
	Next slide, please.
	[Slide]
	I asked Dr. Ammann yesterday whether or not he had used 
	these corrections and taken them back in time.  He said 
	that he had, that he has a paper that is submitted for
	review on this, and I want to make clear that this hasn't 
	been peer reviewed yet.  It is the same correction applied
	to the data going back a thousand years, and this is the 
	result.  The blue line is the emulation of Mann 1999.  The 
	red line is the result.  And in fact it does not continue 
	to go up.  And this is going to be my last slide so don't 
	be concerned.  There are a lot more slides in your 
	handout.  I want to point out here that if you look at 
	the medieval times here which would be the first couple 
	of frames from the left in that graph it is warmer than 
	what you see to the right of that.  There is a Medieval 
	Warm Period on this graph.  It is just weak, and that 
	is completely consistent with the scientific examination 
	of paleoclimate over the last 20 years. There has been 
	a consistent trajectory and this is completely consistent 
	with that.  Thank you.
	[The prepared statement of Dr. Jay Gulledge follows:]

PREPARED STATEMENT OF DR. JAY GULLEDGE, SENIOR RESEARCH FELLOW, 
PEW CENTER ON GLOBAL CLIMATE CHANGE

Mr. Chairman, Ranking Member, and Members of the Committee:
Thank you for the opportunity to speak today. I am Jay Gulledge, 
Ph.D., Senior Research Fellow for Science and Impacts at the Pew 
Center on Global Climate Change.  I am also an Adjunct Assistant 
Professor at the University of Louisville, which houses my academic 
research program on carbon cycling.
The Pew Center on Global Climate Change is a non-profit, 
non-partisan and independent organization dedicated to providing 
credible information, straight answers and innovative solutions in
the effort to address global climate change.  In our eight years of
existence, we have published almost seventy reports by experts in 
climate science, economics, policy and solutions, all of which have
been peer-reviewed and reviewed as well by the companies with which
we work.
Forty-one major companies sit on the Pew Center's Business
Environmental Leadership Council, spanning a range of sectors, 
including oil and gas (BP, Shell), transportation (Boeing, Toyota), 
utilities (PG&E, Duke Energy, Entergy), high technology (IBM, Intel,
HP), diversified manufacturing (GE, United Technologies), and 
chemicals (DuPont, Rohm and Haas).  Collectively, the 41 companies
represent two trillion dollars in market capitalization and three 
million employees.  The members of the Council work with the Pew 
Center to educate the public on the risks, challenges and solutions 
to climate change.  
If you take nothing else from my testimony, please take these three
points:
1.  The scientific evidence of significant human influence on 
climate is strong and would in no way be weakened if there were no
Mann hockey stick.
2.  The scientific debate over the Medieval Warm Period (MWP) has 
been gradually evolving for at least 20 years.  The results of the 
Mann hockey stick simply reflect the gradual development of thought
on the issue over time.
3.  The impact of the McIntyre and McKitrick critique on the 
original Mann paper, after being scrutinized by the National Academy 
of Science, the Wegman panel and a number of meticulous individual 
research groups, is essentially nil with regard to the conclusions
of the Mann paper and the 2001 IPCC assessment.
The science of climate change is an extraordinary example of a 
theory-driven, data-rich scientific paradigm, the likes of which,
arguably, has not occurred since the development of quantum 
mechanics in the first half of the twentieth century. The product 
of this strong scientific framework is a body of strong, 
multifaceted evidence that man-made greenhouse gases are causing 
contemporary global warming, and that this warming trend is 
inducing large-scale changes in global climate. The primary evidence
is based on physical principles and observational and experimental 
analysis of contemporary climate dynamics, as opposed to analyses
of past climates, which are the subject of this hearing. We can
now say with confidence that the evidence of human influence on
climate is strong, as described by Dr. Cicerone.
Although paleoclimatology - the study of ancient climates - is an 
important part of the climate science frame work, reconstructions
of temperature over the past millennium play a secondary, 
expendable role in the larger body of evidence, as stated in the
recent NAS report titled, Surface Temperature Reconstructions for
the Last 2,000 Years: "Surface temperature reconstructions are 
consistent with other evidence of global climate change and can 
be considered as additional supporting evidence" (National 
Research Council 2006, p. 23; hereafter referred to as the NAS
report). Dispensing with such reconstructions entirely or 
proving them fundamentally flawed would have little, if any, 
impact on our understanding of contemporary climate change. This 
statement does not imply that millennial climate reconstructions 
are unimportant, but their main influence will be in the future,
when their potential to reveal how climate varied across the 
earth's surface from year-to-year in the past (i.e. an annual 
record of spatially explicit climate dynamics) is fully realized. 
At that point, such reconstructions will be used in a manner
parallel to thermometer records today. This capability would 
contribute significantly to resolving the current genuine debate 
in climate science, which is not about whether humans are 
changing the climate-a point over which there is no scientific 
controversy-but is about how much human influences will change 
the climate in the future as a result of greenhouse gas 
accumulation and other forcings we apply to the climate system.
In other words, the goal of spatially explicit paleoclimate 
reconstructions is to help climatologists determine how 
physical forcings, such as solar radiation, volcanic eruptions,
land-use changes, and changes in atmospheric greenhouse gases,
have affected the planet in the past, so that we can improve 
estimates of how they will do so in the future. 
The early MBH reconstructions (Mann et al. 1998; Mann et 
al. 1999; hereafter referred to as MBH98 or MBH99 or,
collectively, MBH) were the first to offer spatially explicit 
climate reconstructions and therefore represented a 
breakthrough in climate change science that continues to 
develop and promises to further our understanding of climate
physics in the future. The Wegman report's conclusion that 
paleoclimatology "does not provide insight and understanding
of the physical mechanisms of climate change" (p. 52), fails
to appreciate that the purpose of Dr. Mann's research is to 
improve our knowledge of physical mechanisms of climate 
change by examining how they operated in the past.
Turning our attention to the methodological issues this 
hearing seeks to investigate, in my opinion, the Wegman 
report failed to accomplish its primary objective, which 
was "to reproduce the results of [McIntyre & McKitrick] in
order to determine whether their criticisms are valid and 
have merit" (p. 7). Although the panel reproduced MM's 
work-verbatim-it only partially assessed the validity, and 
did not at all assess the merits, of the criticisms 
directed toward the MBH reconstructions. For instance,
MM (McIntyre and McKitrick 2003; McIntyre and McKitrick 
2005; heafter referred to collectively as MM) allege that
the so-called MBH "hockey stick" result is biased by 
methodological errors that undermine the conclusion that 
the late 20th century was uniquely warm relative to the 
past 1000 years. This critique only has merit if, after 
correcting for the errors pointed out by MM, the resulting 
reconstruction yields results significantly different from 
the original result that can no longer support the claim 
of unusual late 20th century warmth. However, the Wegman 
Report takes no steps to make such a determination. 
Fortunately, a different group, one well qualified both 
statistically and climatologically to tackle this question
of merit, had already performed the task several months 
before the Wegman Report was released. The study by Wahl & 
Ammann (In press; hereafter referred to as WA06), was 
peer-reviewed and accepted for publication in the journal,
Climatic Change, early last spring, and has been publicly 
available in accepted form since last March 
(http://www.cgd.ucar.edu/ccr/ammann/millennium/refs/ 
WahlAmmann_ClimChange2006.html). This study, titled, 
Robustness of the Mann, Bradley, Hughes Reconstruction of
Northern Hemisphere Surface Temperatures:  Examination of 
Criticisms Based on the Nature and Processing of Proxy 
Climate Evidence, carefully reproduced the MBH98 
reconstruction and then used their faithful reproduction 
to test MM's suggested corrections. They tested each of 
the criticisms raised by MM in all of their published 
papers, including both the peer-reviewed and non-peer-
reviewed papers. Given that this report specifically 
examined MM's criticisms, including the decentering issue
that was the main focus of the Wegman report, it is
unfortunate that the Wegman report dismissed it in a
footnote (p. 48) as "not to the point."
WA06 have performed a meticulous and thorough evaluation
of MBH98, and the answers that this committee seeks about
the MBH reconstructions are to be found within this report.
After examining each of MM's three methodological 
criticisms, WA06 accepted two of them as valid, and have 
used them to correct the MBH98 reconstruction. I will now 
show you what effect these corrections have on the MBH98
reconstruction, and then reconsider the uniqueness of the 
late 20th-century warming trend in the light of these 
corrections. 


The original MBH98 "hockey stick" is shown as a gray line 
(Fig. 1). The WA06 reproduction of MBH98 is shown in red 
(Fig. 1). Except for a couple of minor simplifications, 
WA06 remained faithful to the original MBH method and
retained all of the original MBH data, including the original
instrumental temperature series from 1992. They wrote their 
own computer code to perform the calculations, using the R 
programming language, as recommended by the MM and the Wegman
report, rather than the original Fortran language used by
Dr. Mann. As you can see, the two reconstructions are 
materially the same. This result demonstrates that MBH98 can
be reproduced based on information available in the original
MBH papers and supplemental information and data available
on the Internet.

Fig. 2. WA06 corrections of MBH98 for accepted MM corrections. 
The left frame shows original WA06 emulation of MBH in red 
and the corrected reconstruction accounting for decentering 
and excluding the Gaspe tree-ring series in blue. The right 
frame shows the same but with the bristle cone pine series 
removed (green line). Instrumental data are shown in black.


With this successful reproduction in hand, WA06 were able to
test the effects of each of MM's criticisms on the outcome 
of the MBH98 reconstruction. After carefully considering the
validity of MM's three criticisms of MBH's reconstruction 
methodology, WA06 agreed that 1) decentering the proxy data
prior to Principle Component analysis and 2) including the 
poorly replicated North American Gasp� tree-ring series from 
1400-1449 both affected the MBH results. After correcting for 
these effects, WA06 obtained the results shown in blue 
(Fig. 2, left frame). The result is a slightly warmer (0.1 
�C) early 15th century, with no other time period affected. 
MM's third methodological criticism surrounding the inclusion 
of the bristlecone/foxtail pine series was rejected for 
several reasons. The right frame in Fig. 2 illustrates that 
excluding these series has little effect on the MBH98 
reconstruction, except to force it to begin in 1450 instead of 
1400, because of lack of a data. Since the exclusion had 
little effect, and losing these data series would hinder 
reconstructions of earlier climate, WA06 rejected this 
criticism.

Fig. 3. Wahl-Ammann corrections of the MBH99 reconstruction 
(Ammann & Wahl, submitted). The original MBH99 reconstruction 
is shown in blue and the corrected WA version is shown in red. 
Corrections were made for the decentering issue and the Gaspe 
tree-ring series. Instrumental data are in black. 

The additional 15th-century warmth revealed by making the 
valid MM corrections still does not approach the warmth of
the late 20th century, so MM's critique cannot yet be said 
to have merit. However, the corrected result creates the 
impression of an upward temperature trend backward in time
before 1400, begging the question of what would happen to 
the Middle Ages in the 1000-year MBH99 reconstruction if it 
were also corrected? Answering that question is requisite for 
determining the merit of MM's critique of MBH. The original 
1000-year MBH99 reconstruction is shown in blue and the 
corrected version is shown in red (Fig. 3; Ammann & Wahl, 
submitted). Carrying the correction back to the full 
millennium reveals that the largest effects remain in the 
early 15th century, and both earlier and later periods were 
less affected. Therefore, there is very little difference
between the corrected MBH98 and MBH99 reconstructions and the 
originals, and the original observation that the late 20th 
century is uniquely warm in the context of the past 1000 years
is not affected. Hence, the valid methodological caveats that 
MM pointed out do not undermine the main conclusions of the 
original MBH papers or the conclusion of the 2001 IPCC 
assessment. 
The scientific debate over the Medieval Warming Period (MWP) 
has been on the same trajectory for at least 20 years, with 
early indications that the MWP was not a globally coherent
event becoming more solid over time. The MBH99 reconstruction
represented an evolutionary step-not a revolutionary change-in
this established trajectory. The 1990 IPCC figure that 
Mr. McIntyre, the Wall Street Journal editorial page, and 
Dr. Wegman have used in their own assessment of past climate 
is a cartoon, as stated by Dr. Wegman in his testimony last 
week. I have confirmed this with a number of individuals who 
were involved with the 1990 IPCC report or with versions of
the schematic that pre-dated the 1990 IPCC report. The 
schematic is not a plot of data and is inappropriate as a
comparison to MBH. The text of the 1990 IPCC report clearly 
states that the figure is a "schematic diagram" and that "it
is still not clear whether all the fluctuations indicated
were truly global" (p. 202). Furthermore, only three sources 
of information were cited and those sources conflicted on 
whether the Northern Hemisphere was warm or cold:  "The late 
tenth to early thirteenth centuries... appear to have been 
exceptionally warm in parts of western Europe, Iceland and 
Greenland... China was, however, cold at this time, but South 
Japan was warm..." Clearly, this report certainly did not 
paint a picture of any consensus regarding a Medieval Warm 
Period as a hemisphere-wide phenomenon and characterizing it 
as such reveals a fundamental misunderstanding of climate 
science.
The 1992 and 1995 IPCC reports continued this same trajectory 
of thought. Four years before MBH99, citing 6 papers-still a 
very limited number by twice as many as were cited in 1990-the
1995 report stated:
There are, for this last millennium, two periods which have
received special attention, the Medieval Warm Period and the
Little Ice Age. These have been interpreted, at times, as 
period of global warmth and coolness, respectively. Recent
studies have re-evaluated the interval commonly known as the 
Medieval Warm Period to assess the magnitude and geographical
extent of any prolonged warm interval between the 9th and 
14th centuries... The available evidence is limited 
(geographically) and is equivocal. ...a clearer picture may
emerge as more and better calibrated proxy records are produced.
However, at this point, it is not yet possible to say whether,
at a hemispheric scale, temperatures declined from the 11-12th 
to the 16-17th century. Nor, therefore, is it possible to 
conclude that the global temperatures in the Medieval Warm 
Period were comparable to the warm decades of the late 20th 
century" (p. 174).
Remember that this was written by a team of climatologists as a
consensus statement. The consensus at this time, as in 1990, 
was that there was no strong evidence of a hemisphere-wide MWP. 
Continuing the same trajectory, the 2001 IPCC Third Assessment 
Report examined evidence from 10 cited sources for the MWP. 
The consensus at this point seemed to be turning to the 
conclusion that the there actually  was a generally warm 
Northern Hemisphere  during the Middle Ages, but that it was
not a strong, coherent pattern of warming:
It is likely that temperatures were relatively warm in the
Northern Hemisphere as a whole during the earlier centuries 
of the millennium, but it is much less likely that a 
globally-synchronous, well defined interval of "Medieval 
warmth" existed, comparable to the near global warmth of the
late 20th century... Marked warmth seems to have been confined 
to Europe and regions neighboring the North Atlantic.
Since the MBH reconstructions were hemisphere-wide, and the
MWP probably was not, it should not surprise us that the 
reconstructions lack a strong MWP (MBH99 does show slightly 
warmer temperatures in the 9th to 14th centuries than in the
15th to 19th centuries).
All available evidence indicates that the situation during the
Middle Ages was fundamentally different that what is happening
with climate today, which is a well-documented, globally 
coherent warming trend that is happening North, South, East, 
and West; at low latitudes and high latitudes; over land and 
over-and into-the sea. There are new data, published earlier 
this year, indicating that the atmosphere above Antarctica has
warmed dramatically in recent decades (Turner et al. 2006). 
There is no large region on Earth where large-scale 20th century
warming has not been detected, which simply cannot be said of 
the MWP.
Wahl and Ammann (2006) have demonstrated that the results of
MBH are robust "down in the weeds":
Our examination does suggest that a slight modification to the 
original Mann et al. reconstruction is justifiable for the 
first half of the 15th century (~ +0.05�), which leaves entirely
unaltered the primary conclusion of Mann et al. (as well as many 
other reconstructions) that both the 20th century upward trend
and high late-20th century hemispheric surface temperatures are 
anomalous over at least the last 600 years. 

The NAS has affirmed the MBH results are also robust in the 
bigger picture, as well: 
The basic conclusion of MBH99 was that the late 20th century 
warmth in the Northern Hemisphere was unprecedented during at 
least the last 1,000 years. This conclusion has subsequently 
been supported by an array of evidence that includes both 
additional large-scale surface temperature reconstructions and
pronounced changes in a variety of local proxy indicators, 
such as melting on icecaps and the retreat of glaciers around 
the world, which in many cases appear to be unprecedented 
during at least the last 2,000 years. Not all individual proxy 
records indicate that the recent warmth is unprecedented, 
although a larger fraction of geographically diverse sites 
experienced exceptional warmth during the late 20th century than
during any other extended period from A.D. 900 onward. (p. 3)

Examination of the IPCC reports through time, as well as the 
primary scientific literature, reveals why the MBH results are
so robust-MBH simply assimilated all the available evidence into
a quantitative reconstruction-evidence that had already been 
evaluated qualitatively as lacking a coherent MWP.
This committee is seeking to know the significance of the 
criticisms leveled at the MBH reconstruction for climate change 
assessments. The significance is that these criticisms have 
resulted in the most thoroughly vetted single climate study in
the history of climate change research. Dr. Tom Karl summarized
the impact most succinctly in his testimony to this committee 
last week when he said that he would stand by the IPCC's 
original assessment:  "If you ask me to give qualifications 
about the findings in the 2001 report with the same caveat in 
terms of defining likelihood, I personally would not change 
anything." Hence, the impact of the MM critique, after being 
scrutinized by the NAS, the Wegman panel, and a number of 
meticulous individual research groups, is essentially nil with
regard to the conclusions of MBH and the 2001 IPCC assessment.
Also relevant to this committee's questions about climate
change assessments is the revelation that climate scientists
do know their business, and that a lack of knowledge of
geophysics is a genuine handicap to those who would seek to
provide what they deem "independent review." If the assessment 
of climate science presented in Mr. McIntyre's presentation to 
the NAS committee, the Wegman Report, and the WSJ is an example 
of what can be expected from those who have not conducted 
climate research, then the investigation launched by this 
committee has demonstrated clearly that "independent review" 
by non-climate scientists is an exceedingly ineffective way to 
make climate change assessments.

References
Mann, M E, R S Bradley and M K Hughes (1998). "Global-scale 
temperature patterns and climate forcing over the past six 
centuries." Nature 392(6678): 779-787.
Mann, M E, R S Bradley and M K Hughes (1999). "Northern hemisphere
temperatures during the past millennium: Inferences, uncertainties,
and limitations." Geophysical Research Letters 26(6): 759-762.
McIntyre, S and R McKitrick (2003). "Corrections to the Mann et 
al. (1998) proxy data base and northern hemisphere average 
temperature series." Energy & Environment 14(6): 751-771.
McIntyre, S and R McKitrick (2005). "Hockey sticks, principal 
components, and spurious significance." Geophysical Research 
Letters 32(3).
National Research Council, C O S T R F T L, 000 Years. (2006). 
"Surface temperature reconstructions for the last 2,000 years." 
from http://www.nap.edu/catalog/ 11676.html.
Turner, J, T a Lachlan-Cope, S Colwell, et al. (2006). 
"Significant warming of the Antarctic winter troposphere." 
Science 311: 1914-1917.
Wahl, E and C Ammann (In press). "Robustness of the Mann, 
Bradley, Hughes reconstruction of northern hemisphere surface
temperatures:  Examination of criticisms based on the nature 
and processing of proxy climate evidence." Climatic Change 
(accepted).

	MR. WHITFIELD.  Dr. Wegman, you are recognized for
	5 minutes.
DR. WEGMAN.  Thank you.  Good afternoon.  I would like to begin 
by summarizing our previous testimony.  Let me first begin by 
circumscribing the substance of our report.  As you know, we 
were asked to provide an independent verification by 
statisticians of the critiques of the statistical methodology 
found in the papers of Dr. Michael Mann, Raymond Bradley, and 
Malcolm Hughes, published respectively in Nature and Geophysical
Review Letters.  These two papers have commonly been referred 
to MBH98 and 99.  The critiques have been made by Stephen 
McIntyre and Ross McKitrick published in Energy and Environment
in 2003, and in that same journal and also in Geophysics Research 
Letters in 2005.  We refer to these as MM03, 05A, 05B, respectively.
	We were also asked about the implications of our assessment.
	We were not asked to assess the reality of global warming, 
	and indeed this is not an area of our expertise.  Our panel
	was composed of myself from George Mason University, 
	Dr. David W. Scott from Rice University, and Yasmin Said, 
	Dr. Said, from the Johns Hopkins.  This ad hoc panel has 
	worked pro bono, has received no compensation, and has no
	financial interest in the outcome.
	The debate over Dr. Mann's principal components methodology
	has been going on for nearly 3 years.  When we got involved,
	there was no evidence that a single issue was resolved or 
	even nearing resolution.  Dr. Mann's RealClimate.org website
	said that all of Mr. McIntyre and Dr. McKitrick claims had 
	been discredited.  UCAR had issued a news release saying that
	all their claims were unfounded, by the way, based on the 
	Ammann paper just referred to.
	The situation was ripe for a third party review of the types 
	that we and Dr. North's NRC panel have done.  Because of the
	very high visibility of the original study, we see no harm 
	and much advantage of having two independent analyses of the
	situation, from quite different perspectives.
	While the two studies overlap on the important topic of 
	Mann's principal components methodology, Dr. North's NRC 
	panel considers topics that were outside the scope of our
	study, such as other temperature reconstructions.  Where 
	we have commonality, I believe our report and the NRC 
	panel essentially agree.  The error in the use of principal 
	components methodology, the NRC panel reported under some
	conditions, the leading principal component can exhibit a
	spurious trend in the proxy-based reconstruction.
	The NRC panel illustrated this with their own spurious 
	hockey stick in Figure 9-2 on page 87 of the report.  Our 
	explanation of this phenomenon was similar, the authors 
	make the seemingly innocuous and somewhat obscure 
	calibration assumption.  Because the instrumental temperature
	records are only available for a limited window, they use 
	instrumental temperature data from 1902-1995 to calibrate 
	the proxy data set.  This would seem reasonable except for 
	the fact that temperatures were rising during this period. 
	So that centering on this period has the effect of making 
	the mean value for any proxy series exhibiting the same 
	increasing trend to be decentered low.
	Because the proxy series exhibiting the rising trend are 
	decentered, the calculated variance will be larger than 
	their normal variance when calculated based on centered 
	data, and hence they will tend to be selected 
	preferentially as the first principal component.  The 
	centering of the proxy data is a critical factor in using
	principal components methodology.
	The effect of decentering was illustrated by us in
	Figure 2, which is Figure 4.3 in our report.  The top panel
	represents the North American Tree Ring PC1 as calculated
	based on the MBH98 methodology.  The bottom panel illustrates
	the PC1 based on the same set of tree ring proxies with the
	centered PCA computation.  We believe that our discussion, 
	together with the discussion from the NRC report should take
	the centering issue off the table.  The decentering 
	methodology is simply incorrect mathematics as was 
	illustrated in our Appendix A as well as with ample 
	simulation evidence in both our report and that of the 
	NRC report.
	I am baffled by the claim that incorrect method doesn't
	matter because the answer is correct anyway.  The method
	wrong plus answer correct is just bad science.  But with
	the centering issue off the table, the question then 
	shifts from principal component analysis to which proxies
	exhibit the hockey stick shape and whether these proxies
	contain valid temperature signals.  We agree with Dr. Mann
	that the hockey stick shape is in some proxies.
	Figure 4 is an image that I showed in our previous 
	testimony showing just six bristlecone pine proxies used 
	in the construction of the North American PC1 series.  The
	hockey stick shapes are clearly visible in the last two 
	proxies.  Given our discussion, it is clear how the 
	decentering methodology will select these and give them 
	prominence in PC1.  So the question is are these valid 
	temperature proxies.  I quote from our report, "Graybill
	and Idso, 1993, specifically sought to show that 
	bristlecone pines were CO2 fertilized.  Bondi et al., 
	1999, suggest bristlecones are not reliable temperature 
	proxy for the last 150 years as it shows an increasing 
	trend in about 1850 that has been attributed to 
	atmospheric CO2 fertilization."  We also know that IPCC
	1996 report stated that the possible confounding effects 
	of carbon dioxide fertilization need to be taken into 
	account when calibrating tree ring data against climate 
	variations.  At the very least, the effect of these 
	proxies on temperature reconstruction should be examined.
	Figure 5 shows Dr. Mann's own illustration, MBH, Internet, 
	2003, of the direct effect of North American tree ring 
	data on reconstruction results in the 15th century.  
	Indeed, it is our understanding as outsiders that all 
	parties agree as to the significance of this tree ring 
	network to final results, and that has made the use of 
	the tree ring network a disputed issue as Mr. McIntyre has 
	just pointed out.
	Figure 6 is also a repeat graphic from my previous 
	testimony.  Please note that the Bristlecone/Foxtail PC1
	proxy is used not only in MBH, but in virtually every 
	subsequent reconstruction.  We do not claim to be experts 
	in dendrology either but it seems to us as outsiders that 
	there are sufficient confounding factors that proxies based 
	on bristlecones should be avoided.  We should add that we 
	were specifically asked to resolve the differences between 
	MPH98/99 and the McIntyre and McKitrick papers.  There is 
	a bewildering array of subsequent work that we were not 
	asked to consider, but which probably deserves much more 
	intense scrutiny.  We would include such refereed papers 
	as Rutherford et al., 2005, and Wahl and Ammann, 2006, 
	which are purported to be written by independent teams, 
	but which are co-authored by Dr. Mann himself in Rutherford 
	et al. and by Dr. Mann's student Dr. Ammann in Wahl and 
	Ammann.
	MR. WHITFIELD.  Dr. Wegman, excuse me for interrupting.  You 
	are about 3 minutes over on the testimony, and we did hear 
	your testimony last week and we have it in the record.  And
	we genuinely appreciate your being back here today, and I 
	am sure we will have some questions for you.
	DR. WEGMAN.  Thank you, sir.
	MR. WHITFIELD.  And you adequately covered last week also 
	the social network and which we appreciate very much.
	[The prepared statement of Dr. Edward J. Wegman follows:]


PREPARED STATEMENT OF DR. EDWARD J. WEGMAN, DIRECTOR, CENTER FOR 
COMPUTATIONAL STATISTICS

Good morning. I would like to begin by summarizing our previous 
testimony. The debate over Dr. Mann's principal components 
methodology has been going on for nearly three years. When we got 
involved, there was no evidence that a single issue was resolved 
or even nearing resolution. Dr. Mann's RealClimate.org website 
said that all of the Mr. McIntyre and Dr. McKitrick claims had 
been "discredited". UCAR1 had issued a news release saying that 
all their claims were "unfounded". Mr. McIntyre replied on the 
ClimateAudit.org website. The climate science community seemed 
unable to either refute McIntyre's claims or accept them. The 
situation was ripe for a third-party review of the types that we 
and Dr. North's NRC panel have done. Because of the very high 
visibility of the original study, we see no harm and much 
advantage of having two independent analyses of the situation, 
from quite different perspectives.
While the two studies overlap on the important topic of Mann's 
principal components methodology, the Dr. North's NRC panel 
considers topics that were outside the scope of our study, such
as other temperature reconstructions. Where we have commonality, 
I believe our report and the NRC panel essentially agree. On the 
error in the use of principal components methodology, the NRC
panel reported, "...under some conditions, the leading principal 
component can exhibit a spurious trend in the proxy-based 
reconstruction. To see how this can happen, suppose that instead
of proxy climate data, one simply used a random sample of 
autocorrelated time series that did not contain a coherent signal. 
If these simulated proxies are standardized as anomalies with 
respect to a calibration period and used to form principal 
components, the first component tends to exhibit a trend, even 
though the proxies themselves have no common trend. Essentially,
the first component tends to capture those proxies that, by 
chance, show different values between the calibration period and 
the remainder of the data." 


The NRC panel illustrated this with their own spurious hockey 
stick in Figure 9-2 on page 87. Our explanation of this
phenomenon is similar. "... the authors make a seemingly innocuous 
and somewhat obscure calibration assumption. Because the 
instrumental temperature records are only available for a limited 
window, they use instrumental temperature data from 1902-1995 to 
calibrate the proxy data set. This would seem reasonable except
for the fact that temperatures were rising during this period. 
So that centering on this period has the effect of making the 
mean value for any proxy series exhibiting the same increasing 
trend to be decentered low. Because the proxy series exhibiting 
the rising trend are decentered, the calculated variance will be
larger than their normal variance when calculated based on 
centered data, and hence they will tend to be selected
preferentially as the first principal component. ... The centering
of the proxy series is a critical factor in using principal
components methodology." 


The effect of decentering was illustrated by us in Figure 2, which
is Figure 4.3 in our report. The top panel represents the North
American Tree Ring PC1 as calculated based on the MBH98 
methodology. The bottom panel illustrates the PC1 based on the 
same set of tree ring proxies with the centered PCA computation. 


To illustrate that this spurious decentering effect is not limited
to just hockey sticks we created an additional illustration based
on the IPCC 1990 temperature curve. With 69 uncorrelated white 
noise proxies and one IPCC 1990 curve, it is clear that decentering
can overwhelm the remaining proxies and preferentially select the 
one anomalous one. 
We believe that our discussion together with the discussion from 
the NRC report should take the "centering" issue off the table. The
decentered methodology is simply incorrect mathematics as was 
illustrated in our Appendix A as well as with ample simulation 
evidence in both our report and that of the NRC report. I am baffled
by the claim that the incorrect method doesn't matter because the 
answer is correct anyway. Method Wrong + Answer Correct = Bad Science.
But with the centering issue off the table, the question then shifts 
from principal component analysis to which proxies exhibit the hockey
stick shape and whether these proxies contain valid temperature 
signals. We agree with Dr. Mann that the hockey stick shape is in 
some proxies.


Figure 4 is an image that I showed in our previous testimony showing
just six sample Bristlecone pine proxies used in the construction of
the North American PC1 series. The hockey stick shapes are clearly 
visible in the last two proxies. Given our discussion, it is clear
how the decentering methodology will select these and give them 
prominence in PC1. Are these valid temperature proxies? I quote from
our report, "Graybill and Idso (1993) specifically sought to show that 
Bristlecone Pines were CO2 fertilized. Bondi et al. (1999) suggest
[Bristlecones] 'are not a reliable temperature proxy for the last 
150 years as it shows an increasing trend in about 1850 that has been 
attributed to atmospheric CO2 fertilization.' ... We also note that 
IPCC 1996 report stated that 'the possible confounding effects of 
carbon dioxide fertilization need to be taken into account when
calibrating tree ring data against climate variations.'" At the very 
least, the effect of these proxies on temperature reconstruction 
should be examined.


Figure 5 shows Dr. Mann's own illustration (MBH, Internet, 2003) of 
the direct effect of North American tree ring data on reconstruction
results in the 15th century. Indeed, it is our understanding as 
outsiders that all parties agree as to the significance of this tree
ring network to final results. And that has made the use of the tree 
ring network a disputed issue.


Figure 6 is also a repeat graphic from my previous testimony. Please 
note that the Bristlecone/Foxtail PC1 proxy is used not only in MBH,
but also in virtually every subsequent reconstruction. We do not
claim to be experts in dendrology, but it seems to us as outsiders 
that there are sufficient confounding factors that proxies based on 
Bristlecones should be avoided. We should add that we were specifically
asked to resolve the differences between MBH98/99 and MM03/05a/05b. 
There is a bewildering array of subsequent work that we were not asked 
to consider, but which probably deserves much more intense scrutiny. We 
would include such refereed papers as Rutherford et al. (2005) and Wahl 
and Ammann (2006), which are purported to be written by independent 
teams, but which are co-authored by Dr. Mann himself in Rutherford et 
al. and by Dr. Mann's student Dr. Ammann in Wahl and Ammann.


Indeed, far from there being uniform agreement on the hockey stick 
shape, B�rger and Cubasch (2005) have reported that a discomforting 
array of different results can be obtained from MBH proxies under 
minor methodological differences. Figure 7 illustrates that while 
there may be reasonable consensus on warming since 1900, i.e. the 
calibration period, as the NRC report suggests, paleoclimate 
temperature reconstruction past 1600 is much more problematic. 
Indeed, on the matter of consensus, the NOAA website titled A Paleo 
Perspective ... on Global Warming has the following contradictory 
statements: "The latest peer-reviewed paleoclimatic studies appear
to confirm that the global warmth of the 20th century may not 
necessarily be the warmest time in Earth's history, what is unique 
is that the warmth is global and cannot be explained by natural 
forcing mechanisms."
 From http://www.ncdc.noaa.gov/paleo/globalwarming/paleobefore.html
Also from the same website: "In summary, it appears that the 20th 
century, and in particular the late 20th century, is likely the 
warmest the Earth has seen in at least 1200 years." 
From http://www.ncdc.noaa.gov/paleo/globalwarming/medieval.html


We do agree with Dr. Mann on one key point: that MBH98/99 were not
the only evidence of global warming. As we said in our report, "In
a real sense the paleoclimate results of MBH98/99 are essentially
irrelevant to the consensus on climate change. The instrumented
temperature record since 1850 clearly indicates an increase in 
temperature." We certainly agree that modern global warming is 
real. We have never disputed this point. We think it is time to 
put the 'hockey stick' controversy behind us and move on. 
I would like to make it clear that our role as statisticians in 
the hockey stick game is not as players in the hockey game, but 
as referees. What we have seen and continue to see is that, not 
withstanding the efforts by Dr. Nychka and others at NCAR, there 
is relatively little interaction between the statistical community 
and the climate science/meteorology communities although the 
latter frequently use statistical techniques. Statisticians in 
general have to pay their mortgages just like everyone else and 
in general cannot afford to do pro bono work such as we have been
doing. We advocated in our report that if statistical methods are
being used, then statisticians ought to be funded partners engaged
in the research to insure as best we possibly can that the best 
quality science is being done. Drs. Nychka and Bloomfield, the 
statisticians involved with the NRC report, raise other issues on 
calibration, validation, and full quantification of uncertainty in
these studies. Indeed there are a host of fundamental statistical 
questions that beg answers in understanding climate dynamics.

Sampling
How were the 70 trees in NOAMER 1400 selected? 
 4 Arkansas
 4 Arizona
 13 California
 12 Colorado
 3 Georgia
 1 Louisiana
 1 Montana
 1 North Carolina
 5 New Mexico
 14 Nevada
 3 Oregon
 1 South Dakota
 3 Utah
 1 Virginia
 4 Wyoming

How representative are these trees of the population of trees 
that grew from 1400-2000? In terms of geography, altitude, and 
type. If these trees seemed "interesting" to various individuals 
who took the core samples, do you believe those trees can/should 
be treated as a "random sample"? Are there biases in the selection 
of these trees? Presumably many trees could not be sampled because 
they had died or been harvested. What is the effect of this 
"censoring" on your data (and your analysis)? Similar questions 
exist about ice cores and how representative such data might be. 
What are the effects of gas diffusion in the ice core layers?

Analysis
What is the correlation between temperature and tree ring growth?
What calibration studies have been performed? The rescaling steps 
taken seem to suggest that the correlation must be near 100%. Is 
that the case? The temperature proxy search is a regression
problem. Why did you choose to use principal components (not 
appropriate for finding a nonstationary mean)? What weights do you
use to combine different proxy types? Why? If the data are not a 
random sample, then what confidence can be given to any modeling 
and to any "error bars"?

Forecasting and Modeling
CO2 modeling shows a rapid increase in the near term. What do the
models show in the longer term? Given the apparent high 
correlation between CO2 and temperature in the model outputs, how
direct is the link in the model itself? What is the difference 
between a true forecast and a "model run"? Do you believe your 
model runs have any statistical validity? The output looks like 
a Taylor series with no higher order terms?

Planning Experiments
What data should be collected that would be most cost-effective in
increasing our understanding of the climatic models and the 
underlying physics (and statistics)? Is all data valuable? How does
one avoid the desire to collect data at sites that appear 
"interesting" beforehand? What are the parallels between modern 
experimental science and experimental medical research of the 1960's?
How many surgeons were "certain" their treatments were superior or 
that drugs were safe and found out otherwise with carefully designed
and controlled studies? Is the risk of global warming so acute that 
such studies are deemed unwise?
Our report is not aimed at criticizing Dr. Mann or his colleagues,
but in outlining a path for doing the science better.  We note that 
the American Meteorological Society has a Committee on Probability 
and Statistics. I believe it is amazing for a committee whose focus 
is on statistics and probability that of the nine members only two 
are also members of the American Statistical Association, the premier 
statistical association in the United States, and one of those is a 
recent Ph.D. with an assistant professor appointment in a medical 
school. The American Meteorological Association recently held the 
18th Conference on Probability and Statistics in the Atmospheric 
Sciences (January, 2006). Of the 62 presenters at a conference with
a focus on statistics and probability, only 8 (12.9%) are members of
the American Statistical Association. I believe these two communities
should be more engaged and if nothing else our report should highlight
to both communities a need for additional cross-disciplinary ties.

	MR. WHITFIELD.  So at this time I will start off the questions,
	and I would direct my first question to Dr. Mann and 
	Dr. Christy and Dr. Cicerone.  If you look at the 1990 U.N. 
	report from the Intergovernmental Panel on Climate Change, it 
	is quite pronounced the so-called Medieval Warming Period.  
	And so the first question I would ask was there a Medieval 
	Warming Period, Dr. Mann?
	DR. MANN.  Let me tackle that first.  Actually the graphic 
	you are referring to in the 1990 report was not an actual 
	numerical estimate.  It was a schematic based on very limited
	evidence in some parts of the globe, and that was actually 
	emphasized in the report that they based that schematic on very 
	limited information.  Another interesting thing about that 
	plot is that it actually ends in 1975.  Now there has been 
	roughly .5 degrees C of additional warming in the climate in 
	the Northern Hemisphere since 1975.  And if you superimpose--
	MR. WHITFIELD.  How much since then?
	DR. MANN.  Point 5 degrees C additional warming since 1975.
	MR. WHITFIELD.  Point 5 degrees.  Okay.
	DR. MANN.  Yes.  So if you superimpose that on the end of 
	that 1990 curve where it stops in 1975 actually the modern 
	warmth is above the medieval peak.  So it actually reinforces 
	the later conclusions shown in the 1996 report and the 2001 
	report.
	But we have learned a lot since then.  For example, we know 
	that the so-called Medieval Warm Period was actually fairly 
	cold in the tropical Pacific.  There is coral data that tell 
	us that it was a La Nina like period.  Now that means that 
	there were large parts of the global surface that were cold 
	at that time.  As we learn more about the regional detail, 
	we realize that it is incorrect to simply label that period 
	as the Medieval Warm Period, and that is why most scientists 
	now call it the Medieval Climate Anomaly.
	MR. WHITFIELD.  Okay.  Dr. Christy, would you make comment 
	about it?
	DR. CHRISTY.  Yes.  Regarding the 1990 picture--
	MR. WHITFIELD.  The Medieval Warming Period.
	DR. CHRISTY.  Some places were obviously warm, other places 
	weren't, and it is one that doesn't look like it has a warm 
	period at that time but there were other places that were 
	warmer than today, I think.
	MR. WHITFIELD.  Okay.  And Dr. Cicerone.
	DR. CICERONE.  I have nothing to add.  I went back and looked 
	at the cartoon after last week's hearing and read all the 
	surrounding pages and I have nothing to add.
	MR. WHITFIELD.  Okay.  Now Mr.--
	CHAIRMAN BARTON.  Mr. Whitfield, could I--
	MR. WHITFIELD.  Yes, sir.  Yes, sir.
	CHAIRMAN BARTON.  Why do we call that a cartoon and these 
	others something different?  I know the methodology is 
	different but I would assume that the 1990 graphic was based 
	on some mathematical evidence.  It may not have been as 
	complicated with as many variables as Dr. Mann's later work, 
	but I don't think they just pulled that out of the air, did 
	they?
	DR. MANN.  Let me comment.  Actually it is a schematic.  It 
	is a cartoon.  It was not a numerical estimate.
	CHAIRMAN BARTON.  They threw spaghetti up on the wall and 
	wherever it stuck is what they put in the chart.
	DR. MANN.  Guided by some qualitative interpretations of 
	historical climate records in a few locations in the Northern 
	Hemisphere.  It was not a quantitative estimate of climate.
	CHAIRMAN BARTON.  There is no averaging, there is no data to 
	back it up?
	DR. MANN.  There is no numerical estimate that I am familiar 
	with that went into that calculation that went into that 
	graphic.  There was no calculation.
	DR. GULLEDGE.  Mr. Barton, I have some--if you please.  I 
	actually spoke to some scientists who a couple have actually 
	retired now who were involved in a 1975 NAS report on climate 
	change that actually used a figure like this.  And I spoke to 
	Dr. Tom Webb who remembers the development of this figure and
	it actually originated from somebody's lecture notes at one 
	time from the early '70s.
	CHAIRMAN BARTON.  There is no data set?
	DR. GULLEDGE.  That is correct.  There is no data set that is
	used in the production of this plot.  There were studies where
	they said it looks like the north Atlantic was warm.  There
	are studies that say China was cold.  You know, we are 
	proposing that there may have been a warm period in the Middle 
	Ages, and to quote from the 1990 IPCC report in reference to 
	this figure it says specifically, "It is still not clear 
	whether all the fluctuations indicated in the diagram were 
	truly global."  And that is directly from the report referring 
	to this diagram.
	CHAIRMAN BARTON.  Thank you, Mr. Whitfield.
	MR. WHITFIELD.  Yes, sir.  Just referring to Mr. Inslee's chart 
	about CO2 concentration levels and temperatures going back 
	400,000 years, it is constantly up and down, constantly up and 
	down.  Now is that something that we normally expect that CO2 
	emissions constantly go up and down for 400,000 years?  Would 
	someone reply to that?
	DR. CICERONE.  May I respond?
	MR. WHITFIELD.  Yes, sir.
	DR. CICERONE.  The CO2 data comes from extracting gas 
	dissolved in ice as was explained last week.
	MR. WHITFIELD.  And where is the Vostock ice core, where is 
	that?
	DR. CICERONE.  It is at a particular region in Antarctica 
	where the ice is so thick that you can actually go back that 
	many years and do reasonable dating.  It doesn't mean that 
	every year is exactly one year but it is pretty good resolution 
	so they crush the ice or melt it.  The problem with melting is
	some of the gas can dissolve in liquid so probably the safest 
	technique is to crush the ice and extract the air.  The CO2
	record is absolutely quantitative.  It shows that through the 
	last four ice ages if you go back to 650 or 700,000 years when 
	the Earth was cold the CO2 amounts were low.
	When the Earth was warm in between the ice ages the CO2 got 
	higher, and the range was about 180 to 280 parts per million.  
	Those are the natural cycles of the Earth.  People have tried 
	very hard to say did the CO2 increase cause the warming or the
	cooling or did the warming and cooling cause the CO2.  The only
	evidence that seems clear is that there were times when the 
	warming preceded the CO2 and the cooling preceded the loss in 
	CO2 but they are nearly linked in time.  So people are 
	scratching their heads, what are the feedbacks that cause this?  
	How did these ice ages start?  What triggered them?  How do we 
	get out of them?
	Methane amounts also track perfectly.  When Earth was warm 
	methane was two-thirds of a part per million.  When it was 
	cold it was one third of a part per million.  Now we are at 
	five-thirds of a part per million so we are out of that range. 
	That is about all I can say.  So the biological process that 
	release CO2 and methane were probably responsible.
	MR. WHITFIELD.  So it is continually going up and down.  Would 
	you anticipate that it would go down at some point in the 
	future or do you feel like it is going to continue to go up?
	DR. CICERONE.  Well, the CO2 that is in the air now is 385 
	parts per million, which is 200 parts per million larger than 
	the 180 minimum at cold times and 100 larger than the CO2 
	maximum at hot times.  It is going to take 200 years for that 
	CO2--if we quit putting CO2 in the atmosphere today and all 
	the plants decomposed, it would take a couple hundred years 
	for the CO2 to fall back to that region.  It is not going to
	happen.
	MR. WHITFIELD.  And what percent of all the CO2 being emitted 
	today would you say is man-made and what percent is natural?
	DR. CICERONE.  Well, the decay in biota and respiration and 
	geological processes put 100 gigatons of CO2 carbon in the 
	air each year.  Combustion of fossil fuels puts in 6 or 7.  
	So the natural inputs are larger by far but the equilibrium 
	of the system as established as Professor North mentioned last
	week is the processes that suck it up are about 100, so the 
	imbalance is the 6 or 7 and about half of that shows up in 
	the air and the other half seems to go in the oceans every 
	year.
	MR. WHITFIELD.  But the natural emissions are overwhelmingly 
	larger than man made but the man-made part is what messes up 
	the equilibrium.
	DR. CICERONE.  Well, numerically they are overwhelmingly 
	larger but the atmosphere seems to think otherwise because 
	the atmosphere is responding to the increase.
	MR. WHITFIELD.  Right.  Now, Dr. Christy, you have done some 
	work on satellites, observations of the Earth's surface, and 
	I read a book a number of years ago entitled "A Moment on the 
	Earth" by a guy named Greg Easterbrook, and there was some 
	part of that where he talked a lot about the satellites were 
	not--the models being used to project global warming and the 
	satellite observations were not in sync.  I am sure I am not 
	expressing it in the proper scientific way but hopefully you 
	may know what I am referring to.
	And I know that some of the work that you did, you received a 
	lot of criticism or not criticism, but people were taking 
	shots at you also because you had an error in your work 
	relating to satellites and you were off like .035 percent of
	one degree or something.  But would you elaborate a little bit 
	about the satellite observations today and how that matches up 
	with the global warming that we hear about from a scientific 
	standpoint?
	DR. CHRISTY.  Yeah, it is curious.  I have a couple papers 
	coming out this year, in fact, in which we show that the 
	evidence indicates the atmosphere is not warming as fast as
	it is typically thought from enhanced greenhouse gases 
	particularly in the tropics, so that is the short answer.
	MR. WHITFIELD.  Okay.  And these papers will be coming out 
	when?
	DR. CHRISTY.  I turned the page proofs back for one yesterday
	so it is probably a couple months.  The other one will 
	probably be about 3 months.
	MR. WHITFIELD.  Okay.  My time has expired.  Mr. Stupak.
	MR. STUPAK.  Mr. Chairman, as a courtesy to Mr. Waxman I am 
	going to yield my time to Mr. Waxman, and I will assume his
	time when his time comes.
	MR. WAXMAN.  Thank you very much, Mr. Stupak.  Mr. Chairman, 
	it is interesting that you are citing Gregg Easterbrook as 
	someone who in the past had been a skeptic, and he recently 
	wrote where he said "as an environmental commentator, I have 
	a long record of opposing alarmism.  But based on the data I 
	am now switching sides regarding global warming, from skeptic
	to convert."
	MR. WHITFIELD.  Well, I mentioned his name so you could bring
	that up, Mr. Waxman.
	MR. WAXMAN.  All right.  Dr. Mann, your work was extensively 
	criticized by Dr. Wegman last week.  He criticized certain 
	statistical aspects of your work and provided testimony on 
	global warming more generally.  However, Dr. Wegman isn't a 
	climatologist, and I would like to give you the opportunity 
	to respond to some of his statements from last week's hearing.
	He stated, "Carbon dioxide is heavier than air." And "if the
	carbon dioxide is close to the surface of the Earth it is 
	not reflecting a lot of infrared back."  Would you care to 
	respond to that statement?
	DR. MANN.  Yes.  It is a somewhat problematic statement on
	a couple levels.  First of all, of course the greenhouse 
	effect is not based on the reflection of radiation, it is 
	based on the absorption of outgoing radiation. Rather than
	escaping to space it is radiated back towards the surface 
	and the surface has to warm up in response to that.  So 
	reflections isn't involved at all.  It is the process of 
	absorption, selective absorption.
	The other problem with that statement is that the well
	mixed atmospheric constituents, oxygen, nitrogen, carbon 
	dioxide, their distribution, their vertical distribution 
	in the atmosphere doesn't have to do with their weight or
	their relative masses.  It just has to do with the basic 
	force balances that act in the atmosphere.  There is gravity 
	and then there are gradients due to the pressure of the 
	atmosphere and these two things have to balance out.  And it
	turns out that all of the well-mixed gases decay with the
	same vertical profile falling to about one-third of their 
	surface concentration at roughly eight kilometers up in the
	atmosphere.  And that is true for CO2 as well as oxygen.
	MR. WAXMAN.  I thought that at the time, and I am glad to 
	hear your response because I knew there was something wrong 
	with that statement.  When Dr. Wegman was asked about your 
	research since 1999 he stated that you had circled your 
	wagons "and tried to defend this incorrect methodology."  I
	would like to know if this is true.  Did you continue to 
	use the same methodology or have you worked to improve your
	approach since 1998?
	DR. MANN.  Thanks for the question.  It is another troubling
	statement that you quote there because of course my 
	collaborators and I have far from circling our wagons, we 
	have been spearheading efforts to develop more sophisticated 
	statistical methodologies for reconstructing climate and 
	rigorously testing those methods using climate model 
	simulation.  We published a number of papers that show that
	the methods we used performed very well in the context of
	climate model simulations where we know the answer.  We 
	don't have to guess because we have the simulation.  There
	were some other statements--
	MR. WAXMAN.  Well, let me asks you about some of the other 
	statements because he attempted to impeach your statistical
	background by complaining that you used non-standard 
	statistical phrases in your research like "statistical 
	skill."  Can you help us understand?  Is this an unusual 
	phrase as Dr. Wegman suggests?
	DR. MANN.  That was another very odd statement on his part, 
	and I found his lack of familiarity with that term somewhat
	astonishing.  The American Meteorological Society considers
	it such an important term in the context of statistical 
	weather forecasting verification that they specifically 
	define that term on their website and in their official 
	literature.  And in fact it is defined by the American 
	Meteorological Society in the following manner: "A 
	statistical evaluation of the accuracy of forecasts or the
	effectiveness of detection techniques."  Several simple
	formulations are commonly used in meteorology.  The skill 
	score is useful for evaluating predictions of temperatures, 
	pressures, et cetera, et cetera, so I was very surprised
	by that statement.
	MR. WAXMAN.  Dr. Wegman testified he thought global 
	warming "is probably less urgent than some would have it 
	be."  He also discounted the impact of increasing the 
	planet's temperature by 2 degrees testifying that he would
	"challenge anybody to go out and tell the difference 
	between 72 and 74 degrees Fahrenheit."  Dr. Mann, the
	impacts of climate changes are a well studied area.  Does 
	Dr. Wegman have any basis for being so cavalier about 
	global warming?
	DR. MANN.  Well, just to provide some context.  The 
	difference between the height of the last glacial period
	when there was more than a kilometer of ice sitting above
	New York City global temperatures were probably only about
	4 degrees colder than they are today so that gives you
	some idea of the dramatic nature of climate associated 
	with fairly moderate changes in global mean temperature.  
	Those changes in global mean temperature are often 
	associated with much larger changes in certain very 
	important regions like the Arctic where the warming over
	the last century is much greater than the global mean, 
	and we have seen melting of perma frost and other impacts
	of that.
	MR. WAXMAN.  He also said that global warming "must be
	understood in the context which is that we have relatively
	speaking a Little Ice Age, which everybody seems to 
	acknowledge, and so it is not so surprising that it is 
	warming if we are coming out of a Little Ice Age."  Does
	Dr. Wegman's statement accurately reflect the scientific 
	consensus?
	DR. MANN.  No.  In fact, the implications are just about 
	the opposite of what he had stated.  In fact, we know with
	the climate models that we have today that embody the 
	basic physics of the atmosphere and the ocean and the
	interactions between them, actually we can describe, we
	can predict and explain the factors that underlied the 
	Little Ice Age and the fact that certain regions like 
	Europe cooled somewhat more dramatically than the rest of
	the globe some time between the 17th and 19th Century.
	It turns out that that is the response of the climate to 
	the changes in natural factors like explosive volcanic 
	eruptions and small changes in solar radiants that were 
	relevant to the past.  Those same models that so successfully 
	describe the Little Ice Age tell us that there is no way to 
	explain the warming of the last century without the influence 
	of human beings on concentration of greenhouse gases in the 
	atmosphere.
	MR. WAXMAN.  So I shouldn't be nostalgic for that Little Ice 
	Age.
	DR. MANN.  Perhaps not.
	MR. WAXMAN.  Did Dr. Wegman ever contact you to talk about 
	your work or ask for any further explanation from you about it?
	DR. MANN.  No.
	MR. WAXMAN.  Some have criticized you for lack of willingness 
	to disclose your data and computer code.  Could you briefly 
	tell us how you have handled the availability of your research?
	DR. MANN.  Well, first of all I would like to draw a 
	distinction between data and code.  The statement was made 
	earlier here that I didn't make my data available until 2004, 
	and that is simply incorrect.  Our entire data set was 
	available on the worldwide web several years before that.  Now
	a code, well, that is a different sort of thing.  It is a 
	matter of intellectual property because it takes a lot of work
	to implement the algorithm that one might be using to perform
	a certain sort of operation, but as long as the algorithm is
	available then other people can independently reproduce your 
	work without having the actual physical code.
	And, in fact, that is what Dr. Wahl and Dr. Ammann have shown.
	They have independently implemented our algorithm in a 
	different programming language that is available to anybody 
	who wants to go to their website to access it.  As a matter 
	of fact, over the past few years we have been making all of
	our codes available for all of the calculations that we do,
	and that is actually a standard that many others in our 
	community, the climate research community, haven't really 
	followed, so we are sort of leading the way there.
	MR. WAXMAN.  Thank you.  I want to ask Dr. Christy about this 
	because you stated that you provided your computer code to 
	other researchers when it has been requested, and you 
	specifically mentioned providing your code to Remote Sensing
	Systems or RSS.  Is that accurate?
	DR. CHRISTY.  We provide the part of the code that was in
	question.
	MR. WAXMAN.  Well, I contacted RSS about your testimony and
	Mr. Frank Wentz sent me a letter last night, and he wrote to
	say, "Dr. Christy has never been willing to share his 
	computer code in a substantial way," and he provides the text 
	of a 2002 e-mail exchange between RSS and yourself.  And 
	according to this letter when asked for your code, you replied
	"I don't see how sharing code would be helpful because there
	are at least seven programs that are executed (several 
	thousands lines of code) and we would be forced to spend a 
	considerable amount of time trying to explain coding issues 
	of the spaghetti we wrote."  In light of this letter, 
	Dr. Christy, I would be interested if you care to clarify your 
	testimony because Mr. Wentz wrote further, "I think the 
	complexity issue was a red herring.  My interpretation of 
	Dr. Christy's response is he simply didn't want us looking over
	his shoulder, possibly discovering errors in his work.  So we 
	had to take a more tedious trial-and-error approach to 
	uncovering the errors in his methods."
	And then he went on to explain "RSS manages data software from
	a large array of climate satellites."  What do you say about 
	that?  That sounds inconsistent with what you have told us.
	DR. CHRISTY.  We shared with them the parts of the code that 
	they were most concerned about.  What is called the drift 
	effect was one of them.  Because ours were machine dependent 
	and so on like that but we did share not only that but we 
	also shared the intermediate data to say, okay, if you 
	implement this code this is the intermediate data you should 
	get, and that is what they published.
	MR. WAXMAN.  I must say I am a politician as all the people 
	here at our dais are and all of us engage in politics as we 
	know it, but here is a session with scientists, and you went
	ahead and attacked Dr. Mann, who is an accomplished and 
	respected climate researcher.  I think you and Dr. Wegman 
	attempted to smear his good name.  Now I just got a letter
	from another person--
	MR. WHITFIELD.  The gentleman's time has expired.
	MR. WAXMAN.  --in your field who says that you haven't been
	forthcoming, so I just want to point out to all of you, we 
	don't do the back biting as frequently as it seems to me that 
	some of you scientists seem to do to each other.
	MR. WHITFIELD.  But Dr. Christy did say that he shared part of
	the code that he asked for.
	DR. CHRISTY.  Yes.  They got what they wanted.
	MR. WAXMAN.  May I ask unanimous consent to put the letter
	from Dr. Wentz in the record?
	MR. WHITFIELD.  Without objection.
	MR. STEARNS.  I would object, Mr. Chairman.
	MR. WHITFIELD.  Okay.  Objection.
	MR. STEARNS.  I object just because I think staff should have 
	an opportunity to see the letter first.
	MR. WHITFIELD.  Okay.
	MR. WAXMAN.  I certainly would share it with staff.  Assuming 
	staff sees no objection from the letter that I received last 
	night, I would like to--
	MR. STEARNS.  Mr. Chairman, you remember last time that I asked
	a letter to be submitted to the record and they objected until 
	they saw it--
	MR. STUPAK.  But we put the letter in.
	MR. STEARNS.  I know, but I produced a letter for the gentleman.
	MR. WHITFIELD.  If I could have order a minute.  We will look at 
	the letter.  We will have staff look at the letter.  In the
	meantime I recognize the Chairman of the full committee for 
	10 minutes.
	[The information follows:]



	CHAIRMAN BARTON.  We are about truth, and my guess is 
	Mr. Waxman's letter helps the truth so we will almost 
	certainly put that in the record.  Dr. Mann, I read your
	prepared testimony and I have listened to your synopsis, and 
	you said something that I didn't see in the prepared testimony. 
	Maybe it was there.  You talked about scientists trying to 
	make certain they don't make categorical statements.  I don't
	know exactly but it sounded, to coin a phrase, plausible what 
	you said.  Now in our opening statements my friends on the
	other side, and they really are my friends.  We get along a 
	lot better off camera than we do on camera.
	Their opening statements seem pretty categorical to me.  
	Their minds seem to me to be pretty made up, that this is a
	major problem and it is time to stop foot dragging and let's get 
	on and fix it.  I don't quite have that religion yet.  I haven't 
	been born again quite yet.  And that is what this is all about.  
	If in fact all these things that my friends, Mr. Inslee and 
	Ms. Schakowsky and Mr. Waxman, believe so fervently are 
	literally factually true without question then we need to move 
	to problem solution.
	But I look at these data sets, I look at these data points, I 
	look at these theories and things, and I see a sign curve 
	phenomenon where the Earth gets warmer, the Earth gets cooler, 
	the Earth gets warmer the Earth gets cooler.  It certainly 
	appears that it is getting warmer faster in this century.  It 
	is certainly plausible that it has got to be partially caused 
	by man-made emissions.  But I think it is a little early to 
	categorically make some of the statements that my friends on 
	the Minority side are making.
	And the reason that we asked you to try to provide your data 
	sets and your codes and stuff is because yours was the very 
	first one and it is referred to.  Now there may be a hundred
	since then and maybe we ought to look at all hundred of them
	, but yours is the one even in the National--the science 
	review--Research Council review.  It talks about that in the 
	executive summary. So do you feel--from everything I can
	find out about you is that you are a very fine person and an
	excellent scientist and totally dedicated to your work, but 
	do you think it is fair to ask you to try to let other people
	verify that first study since it seemed to have such an 
	impact on the community?
	DR. MANN.  Well, no, I don't think it is unfair at all to 
	expect the scientific community to validate previous results
	and to refine them, and that process has been occurring over 
	the past 10 years since our work was begun.  I think the 
	National Academy members at their press conference said 
	something to the effect that they felt that the scientific 
	process had worked quite well in this area in that methods 
	have been refined, new proxy data have become available.  
	Multiple estimates are now available where there were three 
	at the time of the IPCC 2001 report.  There are now more
	than a dozen different estimates.  There are also independent
	model simulations--
	CHAIRMAN BARTON.  You don't think it is unfair to have a 
	little scrutiny to the--if it is a conclusion, anybody has a 
	right to a conclusion and an opinion but when it gets into 
	the mainstream that it is just a given that is what I take a
	little exception to even today.  Now I want to ask a 
	follow-up question.  Dr. Wegman said when he tried to get 
	enough information to try to verify the model, verify the 
	algorithm, he says he had some trouble getting that.  Now you
	talked about codes and algorithms.  What is the difference, 
	and I am not a statistician and I am not a climatologist or a
	paleoclimatologist.  What is the difference between a code 
	and an algorithm?
	DR. MANN.  Okay.  Let me try to use an analogy.
	CHAIRMAN BARTON.  Use a simple one.
	DR. MANN.  I will do my best.
	CHAIRMAN BARTON.  The simpler, the better.
	DR. MANN.  Well, let's think of an algorithm is--suppose you
	were trying to build a house.  And you wanted to build a house
	and the data would be the materials you need to build the 
	house, the nails, the wood, et cetera.  The algorithm would be 
	the architectural plan.  Now what would the code be?  Well, 
	imagine that instead of builders you had a computer to make your
	house for you.  Well, the code would be implementing the 
	architectural plan by telling the computer to pick up the 
	hammer, pick up the nail, hammer it in.  And so the code is
	simply implementing the algorithm but the real scientific
	process is embodied within the algorithm, and the algorithm is 
	what has been independently reproduced.
	CHAIRMAN BARTON.  What is proprietary about a formula or 
	mathematical model that tries to compute something as 
	gargantuan as world climate over 2,000 years?  I don't see 
	anybody making any money on that.  I mean if you put it out 
	there and said this is what is happening and try to predict 
	the future, why should that not all be made available in some 
	public way that independent reviewers can try to replicate it?
	DR. MANN.  Well, let me preface this by putting out that we 
	now as a matter of course do make available our codes that we 
	have written to implement these different methods and so the
	Rutherford et al. paper that was shown earlier reproduces 
	essentially the original reconstruction, that entire code can 
	be downloaded from our website.
	CHAIRMAN BARTON.  If we asked, which we are going to, asked 
	Dr. Cicerone--we are going to ask him to review some of these 
	recommendations that Mr. McIntyre and Dr. Wegman and others 
	have made, but one of them is going to be that because the 
	stakes are so big and the consequences are so big that these 
	models and data sets and things be made available in some way 
	that they can be verified.  Do you have a problem with that?
	DR. MANN.  No.  I think this is a bigger question than one 
	that should be asked of me.   There are bigger questions about 
	intellectual property rights, and people--the scientific 
	community and the policy makers need to work that out, what 
	is the balance between making sure that scientists are 
	allowed to write a code, spend a whole lot of time doing it 
	and be able to implement it and use it without immediately 
	having to turn it over to somebody else who suddenly then 
	gets all of their intellectual contributions over a several 
	year period.  So I think there is a balance there.  I don't 
	disagree with the premise of what you are saying.
	And I think there is the issue that Dr. Christy brought up 
	earlier, if you take, for example, our 1998 work, well, that 
	was a program, I think you alluded to this last week, it was 
	written in Fortran and a fairly--
	CHAIRMAN BARTON.  I was stunned to know that that program 
	was still in existence.
	DR. MANN.  It is still more widespread than you might think
	actually.
	CHAIRMAN BARTON.  What generation is it now because I was 
	up to Fortran 4.
	DR. MANN.  It was 90 and then--and we were back in F77, 
	Fortran 77 is what we wrote this program in.  So there is the 
	issue of platform dependence.  And now we are getting away 
	from that.  For example, we write all of our codes now in MAT 
	Lab, which is a portable programming language and anybody who 
	has MAT Lab can implement it.  And that is the direction 
	things are moving but to apply the standard to work that was 
	done 10 years ago may be unfair because the standards have 
	changed.
	CHAIRMAN BARTON.  Dr. Christy, I read your testimony, and I 
	want to compliment you on its preparation and your 
	forthrightness.  On page 11 you talk about, in the second 
	paragraph, that the issue of climate model evaluation has 
	been performed mostly by the modelers themselves.  It is 
	my view, this is you speaking here, and recommendation that
	policy makers would learn much from independent hard-nosed 
	assessments of these model simulations by those who are not 
	directly vested in the outcome.  Some of this is going on 
	but the level of support is minimal.  Do you still stand by 
	that?
	DR. CHRISTY.  Yes, I do.  I think probably any scientific 
	endeavor could stand with independent eyes looking over it.
	CHAIRMAN BARTON.  Dr. Cicerone, do you agree with that 
	statement?
	DR. CICERONE.  The more the merrier.  I have done a lot of 
	mathematical modeling maybe 15 or 20 years ago, and I 
	remember efforts to try to compare models where 
	unfortunately what happened was everybody said, well, 
	let's put the same assumptions in the models and see how 
	they do.  And I think it worked against the science because 
	it created less independence.  So to do this kind of 
	exercise I think we have to take everything into account but 
	generally it is a good idea in my opinion.
	CHAIRMAN BARTON.  I know I am over time.  I want to read one 
	more paragraph in Dr. Christy's testimony because it kind of 
	encapsulates the policy dilemma that we are faced with and 
	ask the panel to comment on it.  And I am quoting, "To 
	understand the scale of what we are dealing with this serves 
	as a rough example.  We know that we on Earth benefit from 
	10 terawatts of energy production today.  To achieve a 
	reduction of the CO2 representing 10 percent, 1 terawatt, of 
	that production we need 1,000 nuclear power plants at 1,000 
	megawatts each.  Massive implementation of wind and solar 
	does not achieve this result and would not provide the 
	baseload power needed by the economies today in any case.  
	Thus, to have a 10 percent impact on emissions from energy, 
	that is growing at the same time, will require a tremendous 
	and difficult and expensive restructuring of energy supplies."
	So even if we accept the problem and move to solution to get 
	a 10 percent reduction in CO2 takes 1,000 megawatt nuclear 
	power plants and it probably doesn't have any impact for 50 
	to 100 years.  Do you all want to comment on that, anybody, 
	other than Dr. Christy, which you can.  It is your statement.
	DR. CHRISTY.  I would just say the energy committee is where 
	a lot of this is going to be done and that is just to give 
	you an idea of the scale of what you are going to be 
	tackling, I think, in the next few years.
	CHAIRMAN BARTON.  That is why I am still a skeptic.  I don't
	want to jump in there especially if this is a naturally 
	reoccurring phenomenon that is exacerbated by human emissions 
	but it is going to happen regardless of what we do.  
	Dr. Cicerone.
	DR. CICERONE.  The numbers that you just summarized from
	Dr. Christy are really intimidating.  I agree with you.  I 
	would like to see us all get together with the elements of a 
	win-win strategy.  There are some actions we can take as 
	first steps, I think, which are truly win-win, and they have 
	to do with energy efficiency.  Just look at it from the 
	United States point of view.  If we could decrease our 
	dependence on foreign energy we would improve national 
	security, we would decrease the trade deficit, we would, I 
	think, stabilize geo politics a little, we would increase 
	national competitiveness by making our manufactured products 
	cheaper.
	When energy prices are high you know better than I our 
	manufactured products have to bear that increase.  We could 
	develop new products which would create new world markets 
	and we could be leaders.  We would decrease the energy costs 
	for households and incidentally slow down the emissions of 
	CO2.  So I think we need a win-win strategy and we can take 
	a bite out of that 1,000 gigawatts with energy efficiency.
	CHAIRMAN BARTON.  My time has more than expired so I 
	apologize.  Thank you all for being here.
	MR. WHITFIELD.  I recognize Mr. Stupak of Michigan.
	MR. STUPAK.  Thank you.  We were talking about that Fortran 
	4 program, and I was just wondering was that during the 
	Medieval Warming Period we have been talking about?  If I 
	may, Mr. Chairman, when I gave my opening statement I had a 
	couple of exhibits.  I should have asked at that time that 
	they be made part of the record with my opening statement.  
	It is the Interfaith Stewardship Alliance that I mentioned 
	and how they were funded by ExxonMobil, so if I may without 
	objection put that as part of my opening statement.
	MR. WHITFIELD.  And we have a copy of it.
	MR. STUPAK.  Yes.
	MR. WHITFIELD.  Thank you.
	MR. STUPAK.  Dr. Cicerone, just speaking of the Medieval 
	Warming Period as it was described in the Wall Street 
	Journal.  We talked a little bit about it earlier.  In 
	fact, are we even sure that even happened in the Northern 
	Hemisphere, that Medieval Warming Period that the Wall 
	Street Journal talked about, that was that chart there, 
	the 1990 chart that we had some discussion about earlier.
	DR. CICERONE.  I am sorry.  Were you addressing that to 
	me, sir?
	MR. STUPAK.  Yes, sir.
	DR. CICERONE.  Okay.  There were certainly records of 
	warm places in that period of time.
	MR. STUPAK.  Warm places and cold places.
	DR. CICERONE.  The question continues to be how extensive 
	was it, how long did it last, and how solid is the 
	evidence.  But, yes, there is evidence of a Medieval Warm 
	Period, but no one can sit here and tell you how 
	geographically extensive it was with strong evidence and 
	how long it lasted.  But, yes, there was a Medieval Warm 
	Period.
	MR. STUPAK.  Dr. Crowley says that even though it was 
	difficult to unequivocally assert that the current warming 
	period is significantly greater than the peak warmth of 
	the Medieval Warm Period there is even less justification 
	for saying that the medieval period was warmer than it 
	is today, is that correct?
	DR. CICERONE.  The committee that Professor North 
	reported on, Professor North from Texas A&M, last week 
	representing the National Research Council, I am pretty 
	sure what they concluded was there was no evidence that 
	that period was warmer than say the year--the decade of 
	the 1990s through 2006.
	MR. STUPAK.  But were considerably warmer?
	DR. CICERONE.  They could not say with strong evidence 
	that each year in the 1990s was warmer than then but there 
	was no evidence that the Medieval Warm Period over an
	extensive geographical region was as warm as the Northern
	Hemisphere is now.
	MR. STUPAK.  Is it fair to say then that neither the 
	pro-hockey stick researchers or the anti-hockey stick 
	researchers can talk with scientific certainty about this 
	medieval period, would that be correct?
	DR. CICERONE.  In certain locations they can where there 
	were records kept, but the question again is how does one 
	location compare with all the others.  For example, some 
	proxy indicators from China inferred what the temperatures 
	were from agricultural crops and stream flows and so 
	forth, which are pretty extensive, but it is hard to 
	compare the timing of those with other strong proxies 
	from elsewhere.
	MR. STUPAK.  Let me ask you this question then.  This is the 
	second hearing we have had on this hockey stick theory, but 
	you were on the National Academy of Science panel that looked 
	at these studies.  Are you telling us basically forget the 
	hockey stick and the Medieval Warm Period, it is a 
	diversion?  Is it your position that global warming is 
	occurring now in the 20th and 21st Century?  Human beings are 
	at least partially responsible.  Our climate will continue to 
	change during the next century and we ought to pay attention 
	to it today.  Is that fair to say?
	DR. CICERONE.  Well, I wouldn't say forget the hockey stick 
	and efforts to reconstruct because what we can learn, and if 
	we work harder we might be able to learn some more about the 
	context, it is still important, but, yes, all the other 
	evidence shows us that the climate is changing and that the 
	human hand is there causing at least part of the warming and 
	that everything we know from physics and chemistry and 
	mathematics is that it is going to continue as long as we 
	continue to load up the atmosphere with greenhouse gases.
	MR. STUPAK.  Do you think it is useful then, Doctor, for us 
	policy makers to hold hearings on just one 8-year old study, 
	Dr. Mann's study, that your committee found was not even the 
	principal evidence for the conclusion about current warming 
	period?
	DR. CICERONE.  I hope that it has been useful.  I have 
	never seen this kind of interest before.  I think a couple--
	I have forgotten who said it earlier on about that this 
	could be--perhaps it was Mr. Bass, who said this could be 
	the beginning of even more serious interest.  So I guess I 
	will wait and see what happens.
	MR. STUPAK.  If there is so much interest in this one and if 
	in the Vice President's book he talks about 928 more peer 
	reviewed articles, so that means if we have two hearings for 
	every one of these we would have about 1,800 hearings just 
	on global warming.  I guess that would be a sufficient 
	amount to get everyone's attention.  Let me ask this 
	question if I can.  There has been a lot of discussion about 
	social networking, and I think it is a practice that is not 
	utilized, should not be utilized.  Peer review and whether 
	it is an accepted practice, isn't it, in paleoclimatology 
	field, social networking, Dr. Cicerone?
	DR. CICERONE.  No.  No, that was I guess kind of an original 
	piece work.  It is not common.
	MR. STUPAK.  Have you looked at or have you reviewed 
	Dr. Wegman's social network analysis of the paleoclimatology 
	field?
	DR. CICERONE.  Last week at the time of the hearing I got a 
	copy and I read it.
	MR. STUPAK.  I know that the National Academy of Science
	has done research of social networking analysis.  Do you 
	have any views you would care to share with us about the 
	field of research?
	DR. CICERONE.  Not today.  I think there is probably some 
	developments that have taken place in the classified arena 
	that I am not totally up on that I would like to find out 
	earlier before I would comment.
	MR. STUPAK.  Is it a relatively new field?
	DR. CICERONE.  Graph theory, the kind of statistical 
	patterns, I think so.  I haven't seen it applied to this 
	kind of a field of study before.
	MR. STUPAK.  What do you think of Dr. Mann's social network 
	analysis of the paleoclimatology field?  Dr. Wegman's.  I am 
	sorry.  I said Dr. Mann's.  Dr. Wegman's.
	DR. CICERONE.  I have no further comment.
	MR. STUPAK.  Okay.  Dr. Wegman, in looking at your report 
	here today and your testimony, I am on page 6, if you would, 
	sir, and I am looking at the paleo perspective on global 
	warming.  And you say these are contradictory statements, and 
	I guess I am a little confused on it and maybe you could help 
	us out.  It says the latest--and I am quoting the first here, 
	the first paragraph on page six.  You got it there?
	DR. WEGMAN.  Yes.  
MR. STUPAK.  "The latest peer-reviewed paleoclimatic studies appear 
to confirm that the global warmth of the 20th Century may not 
necessarily be the warmest time in Earth's history, what is unique is 
that the warmth is global and cannot be explained by natural forcing 
mechanisms."  And it says also from the same website, and this is a 
NOAA website, "In summary, it appears that the 20th Century, and in 
particular the late 20th Century, is likely the warmest the Earth has 
seen in at least 1,200 years."  How is that inconsistent?  You said 
contradictory statements.  How is that contradicting?
	DR. WEGMAN.  Well, at one stage people are suggesting that 
	it is the warmest and another stage it is saying it not 
	necessarily the warmest.  Being likely is a phrase that has 
	been bandied about quite a bit.
	MR. STUPAK.  But aren't those really different time frames?  
	One is talking about 1,200 years, the other one is talking 
	about the 20th Century and Earth's history, it seems like, 
	because one says the 20th Century and particularly the late 
	20th Century is likely the warmest, and the other one is 
	talking about the earth's history.  So that is why I didn't 
	see it as inconsistent.  One is talking about 20th Century, 
	late 20th Century, and the other one is talking about all of 
	Earth's history, so that is why I didn't see the 
	inconsistency.  Do you see what I am saying, those two 
	statements?
	DR. WEGMAN.  Yes, sir, I see what you are saying.
	MR. STUPAK.  Dr. Mann, if I may ask you a question.  I want 
	to go back to this social network.  Dr. Wegman has 
	hypothesized that you have a social network of 42 other 
	scientists and that they cannot independently evaluate your 
	work because they have at various times co-authored work 
	with you.  This may be based on his belief that people who 
	interact regularly will foster a common attitude or 
	identity.  What is your response to that?
	DR. MANN.  Well, frankly, I was a bit baffled by that 
	finding.  My profession is highly competitive.  We often 
	disagree publicly.  Scientists disagree publicly and in 
	our articles, with each other on certain matters, and yet 
	we can co-author on other areas where we agree so there is 
	no contradiction in--
	MR. STUPAK.  Well, do you have peer review of your articles 
	by people who don't agree with you?
	DR. MANN.  I have probably had articles rejected because of 
	reviews by people who were co-authors with me on other 
	articles.  In fact, I am quite certain that is the case.  Of 
	course, Dr. Christy and I are co-authors and yet there are a 
	lot of issues in the science that we don't agree on.  So I 
	was very surprised by that.  I was flattered by that.  The 
	implication that as a post doc when I started this work back
	in the late 1990s that I was sort of the center of the entire 
	field of climate research but it is as incorrect as it is 
	flattering.
	MR. STUPAK.  You don't dominate the thinking of the entire 
	paleoclimatology community, do you?
	DR. MANN.  Well, I don't know if I do now but I am sure I 
	didn't back in the late 1990s.
	MR. STUPAK.  My time is up.  Thank you, Mr. Chairman.
	MR. WHITFIELD.  Thank you.  At this time I recognize 
	Mr. Stearns of Florida.
	MR. STEARNS.  Thank you, Mr. Chairman.  Mr. McIntyre, you 
	are the only one who doesn't have a Ph.D. here on the table 
	so I thought I would ask you this question.  As I understand 
	your background, your undergraduate degree is mathematics.  
	Is that from Oxford?
	MR. MCINTYRE.  My degree in mathematics was from the 
	University of Toronto but I attended Oxford subsequently.  I 
	think my stay there probably overlapped with that of 
	President Clinton's.
	MR. STEARNS.  Oh, good.
	MR. MCINTYRE.  I think we might have played rugby against 
	one another.
	CHAIRMAN BARTON.  We hope you did a little more studying than 
	he did.
	MR. STEARNS.  Well, you know, I just want to give you your 
	due here.  We have heard in testimony that Drs. Wahl and 
	Ammann have reproduced Dr. Mann's work and shown your 
	criticism to be invalid, and I guess--is this true and were 
	your criticism erroneous?  I will give you an opportunity to 
	respond to that.
	MR. MCINTYRE.  Well, a couple of points.  First of all, the 
	code that we used to emulate Dr. Mann's work reconciles 
	almost exactly with that of Wahl and Ammann. And so any 
	conclusions that differ are not because of differences in 
	how we have emulated the reconstruction.  They think that 
	certain steps are fine, we don't.  They have in my opinion 
	not carefully considered the implication of bristlecones. 
	Our codes reconcile so right now I am confident in our 
	conclusions that if you remove the bristlecones you have a 
	major impact on the final results.
	Last December, I met with Ammann in San Francisco and 
	suggested to him that since our codes reconciled so closely 
	that it would make sense if we co-authored a paper in which 
	we set down the points that we agreed on, set down the 
	points we disagreed on in an objective way so that we didn't 
	seem to be launching missiles at one another and creating 
	more controversy.  I said that we could declare an armistice 
	for 6 weeks until we accomplished this, and if we didn't get 
	to conclusion everybody would go back to square one and that 
	each of us could write separate appendices, say where we 
	disagreed.
	I formally sent e-mails to him suggesting that.  He told me 
	in San Francisco that if he did that that that would 
	interfere with his career advancement.
	MR. STEARNS.  Dr. Wegman, I am going to give you an 
	opportunity to respond to some of the testimony today.  The 
	testimony of both Dr. Gulledge and Dr. Mann draw upon the 
	findings of Dr. Wahl and Ammann to suggest your work 
	doesn't matter.  Let me give you an opportunity to respond 
	to that.
	DR. WEGMAN.  Well, I think although the social network 
	analysis has been sort of dismissed the amazing thing to me 
	is that these supposed independent replications of the 
	original Mann work are done by Rutherford et al., which 
	includes the top seven people in the social network that we 
	identified last week.  Every one of them is in there, and 
	they are frequent co-authors with Dr. Mann.  So I can 
	hardly see how that is an independent replication of his 
	original work.
	Secondly, on Dr. Mann's r�sum� he lists Dr. Ammann as one
	of his students as a co-advisor to him although Dr. Ammann 
	does not list him as an advisor.  But it is clear to me 
	that Wahl and Ammann are not independent agents as well.
	MR. STEARNS.  And that goes to this idea of the social 
	network you are talking about?
	DR. WEGMAN.  Yes.  We never claimed, by the way, that 
	Dr. Mann was, in 1998 as a post doc was the center of the 
	social network.  What we are saying is that subsequently 
	he has 42 co-authors many of whom, particularly the top 
	seven in the block we identified, who are frequent 
	co-authors with him and co-authors with each other, and 
	there is some element of thinking that if they are frequent 
	co-authors they are thinking the same way.
	MR. STEARNS.  Is there anything else that you have heard 
	Dr. Mann say earlier that you would like to comment on?  
	You are welcome to go across the spectrum.
	DR. WEGMAN.  Well, first of all, in the question that 
	Mr. Waxman mentioned about the carbon dioxide distribution, 
	that was prefaced by a comment by me that I didn't know 
	anything about this but I suppose, for example, that carbon 
	dioxide, so that was purely a hypothetical conjecture which I 
	did not mean to be taken as testimony.  It was also clear in 
	the discussion that even Dr. North talked about a barrier of 
	carbon dioxide at high levels of the atmosphere so he gave in 
	his diagram an illustration that carbon dioxide was not mixed 
	so that certainly is something that should be clarified.  I 
	did not mean to testify that carbon dioxide sat at the ground 
	level.  That certainly was not what I was saying.
	MR. STEARNS.  Any other thing that has come up that you wish 
	to comment on either that Dr. Mann or others have spoken on 
	or perhaps we as members have spoken on you would like to--
	DR. WEGMAN.  Well, I stand by the statements that I have made 
	and particularly in the written testimony that I didn't get a 
	chance to comment on.   My own sense is that if you look at, 
	for example, this matter of statistical skill, it doesn't 
	matter that the American Meteorological Society says what 
	statistical skill is.  Statisticians do not recognize that 
	term.  I went around to a whole dozen or so of my 
	statisticians network and asked them if they knew what they 
	were talking about.  It is my contention that there is a gulf 
	between the meteorological community and the statistical 
	community.
	We examined, for example, this committee that is on 
	probability and statistics of the American Meteorological 
	Society.  We found only two of the nine people in that 
	committee are actually members of the American Statistical 
	Association, and in fact one of those people is an assistant 
	professor in the medical school whose specialty is 
	bio-statistics.  The assertion I have been making is that 
	although this community, the meteorological community in 
	general and the paleoclimate community in particular, used 
	statistical methods.  They are substantially isolated.  They 
	are using our methods but not talking to us.  In contrast, 
	we are not doing meteorology and--
	MR. STEARNS.  You are talking to them.
	DR. WEGMAN.  We are talking to them.
	MR. STEARNS.  I understand.
	CHAIRMAN BARTON.  Would the gentleman yield just for 
	clarification, please?  Dr. Mann in his testimony referred to 
	this Dr. Ammann and Wahl study who said they have recentered 
	the data and the conclusion is the same if I understood him 
	correctly.  Could you comment on that because one of your 
	points was when you center it correctly the conclusions don't 
	follow.
	DR. WEGMAN.  The studies are done in different ways.  There 
	is the so-called CFR methodology, the CPS methodology, and in
	I believe it was Dr. Mann's 2005 report he illustrates several 
	different studies that do this.  One of the things that is 
	critical is the set of proxy data that you use when you are 
	trying to replicate these studies.  And in fact if you use a 
	nice set of proxies that all have the same signal in them 
	then it really doesn't matter a whole lot what methodology you 
	use.  If you use a very mixed set of proxies that have some 
	noise and different kinds of structure in it then it does 
	matter what kind of--
	CHAIRMAN BARTON.  It goes to Mr. McIntyre's point that 
	depending on the data set you use it is the result you are 
	going to get.
	DR. WEGMAN.  That is right.
	CHAIRMAN BARTON.  If I understood him correctly.
	MR. STEARNS.  Reclaiming my time.  Mr. Christy, Dr. Christy, 
	have you read Dr. Wegman's report, and, if so, what is your 
	opinion of his working conclusion?  I understand you are one 
	of the individuals that was in the group that developed the 
	National Research Council on surface temperature 
	reconstruction of the last 2,000 years, so I would 
	appreciate, Dr. Christy, your comment.
	DR. CHRISTY.  This is the short answer.  I have not read 
	the report.
	MR. STEARNS.  You have not read the report?
	DR. CHRISTY.  No, I am sorry.
	MR. STEARNS.  Okay.  Dr. Cicerone, you are the President of 
	the National Academy of Science.  Dr. Wegman is an appointed
	member of the National Academy of Science Board of 
	Mathematical Sciences and Their Application.  He is chair 
	of the NAS Committee on Applied and Theoretical Statistics, 
	highly credentialed in math and statistics, wouldn't you 
	say?  Shouldn't we take his judgments on statistical matters 
	very seriously, and don't they carry significant weight?  
	Would you say his judgment about statistical matters is 
	important and that he has credibility based upon those 
	credentials?
	DR. CICERONE.  Yes.
	MR. STEARNS.  So there is some attempt by some folks to make 
	some of his findings not correct but based upon what you just 
	said this man is highly credible in math and statistics and 
	we should take his judgment particularly on statistical 
	matters with a high credibility?
	DR. CICERONE.  Yes, but not on the mixing of gases.
	MR. STEARNS.  Not on the mixing of gases.  All right.  Thank 
	you, Mr. Chairman.
	MR. WHITFIELD.  The chair recognizes Mr. Inslee.  Oh, no, 
	Ms. Schakowsky.  I am sorry.  Ms. Schakowsky.
	MS. SCHAKOWSKY.  Thank you, Mr. Chairman.  I want to begin 
	by referring to the end of Dr. Christy's testimony where you 
	drew on a certain kind of expertise where you were a 
	missionary in Africa, and you end with a plea.  And I just 
	want to quote from the testimony.  It says, speaking of the 
	people in Africa you say, "They are far more vulnerable to 
	the impacts of poverty, water, and air pollution, and 
	political strife than whatever the climate does." I actually
	found that to be a pretty strange comment from someone who 
	is the chair of the Earth System Science Center and deal 
	with climate.
	And I wanted to actually ask Dr. Cicerone don't those issues 
	of certainly of water and air pollution, et cetera, are they 
	unrelated entirely to issues of climate?
	DR. CICERONE.  No.  Of course they are related.  I don't 
	know what Dr. Christy would answer to the question of what 
	he meant, but, yes, it is clearly related.
	MS. SCHAKOWSKY.  So I was really confused by that because, 
	first of all, I have to tell you I resented that a little 
	bit.  I close with a plea to remember the needs and 
	aspirations of the poorest amongst us when energy policy is 
	made as if to say that those of us who would ask for some 
	changes in business as usual and energy as usual somehow
	are not taking into consideration the poor people of Africa. 
	So I found that a condescending remark, I have to tell you.
	But are not those things--because I have to tell you, 
	Dr. Christy, that precisely for the reasons of the kind of 
	impact it will have on human life including drought and 
	exacerbating poverty and even you mention political strife, 
	war water actually do worry me a bit.  So how do you 
	segregate that from climate issues?
	DR. CHRISTY.  Was that water wars?
	MS. SCHAKOWSKY.  You said political strife.  I would say 
	that if we end up with a situation where people are fighting 
	over water or limited food supplies because of drought that
	that could be related to the climate, could it not?
	DR. CHRISTY.  We don't know what is going to happen, for 
	example, with the water cycle as the climate evolves so--
	MS. SCHAKOWSKY.  The overall statement about water and air 
	pollution, are they unrelated to climate?
	DR. CHRISTY.  We know today that people die because of water 
	pollution, air pollution and those other things.  Those are 
	issues that we know today and can assess and determine how 
	answers and solutions can be found.  So those are critical 
	things to do today.  And I am sorry if that last line came 
	across condescendingly.  When you live with the people as I 
	did you know that they don't have much of an advocacy in 
	places.
	MS. SCHAKOWSKY.  Actually in the Congress they do have a 
	number of people who care and advocate on their behalf.  I 
	wanted to get to that and it is a perfect lead into the 
	Chairman's question, and what do we know, this was his 
	question, and so I wanted to look at Dr. Gulledge's materials 
	that he provided.  And again I would like to ask him or 
	anyone, it says in your presentation, Dr. Gulledge, human 
	activities are increasing atmospheric greenhouse gases, that 
	that is unequivocally agreed to in the scientific community. 
	The Earth is warming unequivocal at an unprecedented rate, 
	confident, so somewhat less.
	Warming over past five decades caused primarily by man-made 
	greenhouse gases, confident.  So let me add one more preface 
	to this question that I would like to put to the panel, first 
	of all, the question of agreement.  We have a panel here 
	where it is three and three, so if there is a reporter 
	looking at this they would say, well, there is three people 
	who agree with this, three that don't, so there is a split 
	here.  So part of my question is does the disagreement over 
	your unequivocal, unequivocal, confident on this panel 
	reflect the scientific community in any kind of accuracy.  
	And I would like to just question these unequivocal and 
	confident ratings.
	DR. GULLEDGE.  Well, I am not sure if you are describing the 
	panel as being three against three on whether they agree with 
	these statements or not, but I suspect that it might not 
	fall out exactly that way.
	MS. SCHAKOWSKY.  Okay.
	DR. GULLEDGE.  It might vary among some of the lower 
	statements and then--
	MS. SCHAKOWSKY.  Then let me ask this, let me ask the 
	panel.  Is there anyone who disagrees with the 
	unequivocal--that it is unequivocal that human activities 
	are increasing atmospheric greenhouse gases?  Is there 
	anybody?  Okay, good.  That the Earth is warming?  Okay.  
	And at an unprecedented rate?
	DR. CHRISTY.  What is the confidence level on that?
	MS. SCHAKOWSKY.  Confident.
	MR. MCINTYRE.  I don't know that it is unprecedented.
	MS. SCHAKOWSKY.  Actually I wanted to ask you--I hope you 
	don't think this sounds rude but when I looked at the 
	witness list I see, you know, everyone has got kind of a
	credential and then it just says your name, so I wanted 
	to ask you about your credentials, Mr. McIntyre, and 
	perhaps it gets into social networks because when I asked 
	for your resume what I found was: for the last 16 years I 
	have been an officer and director of several small public 
	mineral exploration companies, previous to that I worked 
	for a large international mining company, and that mainly 
	it is your experience in mineral exploration industry that 
	you tout in your resume and your background.  I don't know 
	if that gets to social networks or not.
	MR. MCINTYRE.  Well, in this case this has nothing to do 
	with any work that I have ever done.  I just became 
	interested in it as a citizen when I read the studies, and 
	I thought that politicians were facing difficult policy 
	decisions so I thought that it would be interesting to 
	examine one particular paper which was being cited by the 
	Canadian government.  It wasn't clear to me how people 
	knew that 1998 was the warmest year in the millennium, and 
	I was just interested in how--
	MS. SCHAKOWSKY.  So are you qualified to make a judgment 
	on whether or not the Earth is warming at an unprecedented 
	rate?
	MR. MCINTYRE.  For the things that I have published on, my 
	statistical and mathematical skills are adequate for what 
	I have published on.  The findings that we have had about 
	principal components have been--
	MS. SCHAKOWSKY.  But are you qualified to comment on whether
	or not the Earth is warming at an unprecedented rate?
	MR. MCINTYRE.  Well, you asked whether the people knew or 
	didn't know.  I am just saying I didn't know.
	CHAIRMAN BARTON.  Will the gentlelady yield?
	MS. SCHAKOWSKY.  Yes.
	CHAIRMAN BARTON.  That group is much more qualified than I am 
	to comment on these things, and yet I have the responsibility 
	as Chairman of the committee to put the bill together to 
	change the way Americans work every day if we decide to do 
	something about it.
	MS. SCHAKOWSKY.  Absolutely.  Absolutely.
	CHAIRMAN BARTON.  The least qualified--I will stipulate--
	MS. SCHAKOWSKY.  And me too.  I am with you.
	CHAIRMAN BARTON.  The quality of the commenters is more on 
	that side of the dais than at least it is in the Chairman's 
	chair.  I am not going to comment on anybody else's 
	qualifications but in a democracy anybody with an opinion is 
	entitled to express that opinion and some are more qualified 
	than others obviously because of their credentials, but I 
	don't think we have a standard of witnesses that says unless 
	you have a Ph.D. you cannot testify before--
	MS. SCHAKOWSKY.  Well, actually we are having a--reclaiming 
	my time.  Actually we are having a conversation today about 
	the science here so it is not just about opinion, and it is 
	relevant, I think, to talk about.  And Dr. Wegman has been 
	pretty up front about what he is qualified to testify to and 
	what he is not, and I think that that is fair and it is fair 
	to ask for individual's backgrounds and what their connections 
	or interests might be.  That is the kind of conversation that 
	we are having.
	But what I really wanted to get to was your question about 
	what is it that we know, and if there is pretty wide agreement 
	or no comment because you don't know that human activity is 
	increasing atmospheric greenhouse gases and that the Earth is 
	warming and that it has certain consequences.  Mr. Chairman, 
	when you said that you are a skeptic the difficulty of the 
	task at hand to me is not a reason to be a skeptic about the 
	science.
	Admittedly, this is a daunting task, and we heard about the 
	1,000 nuclear power plants or whatever it could take, but we 
	also heard practical suggestions from Dr. Cicerone about 
	energy efficiency that we could make a start on this.  And 
	so if there is widespread agreement that human activity is 
	contributing to this that this climate--that the warming of 
	the climate is happening, that it can have very detrimental 
	effects.  I am anxious to understand why we don't just move 
	toward solution at this point, and that is what I really was 
	getting to so I have over stepped my time, and I thank you, 
	Mr. Chairman.
	MR. WHITFIELD.  Thank you.  And at this time I will recognize 
	Mrs. Blackburn of Tennessee.
	MRS. BLACKBURN.  Thank you, Mr. Chairman, and you all are 
	very patient with us.  As I said in my opening remarks, I 
	think a lot of this is born out of curiosity of knowing what 
	the truth is and being able to have some answers.  And I will 
	tell you one of the reasons I have such an interest in this.  
	I have a mom who is 81 years old who has been very involved 
	in conservation efforts all of her life.  She won the Keep 
	America Beautiful Lifetime Achievement Award here about 15 
	years ago, and she is very careful in her instruction to her 
	children and her grandchildren that one of the things we 
	have to be very careful about is environmental extremism 
	which many times hurts our argument for actually being good 
	conservationists and leaving this Earth in better shape than 
	we have found it.
	And so when we have studies that seem to go around the horn 
	and then they can't be substantiated and they are coming out 
	as government proof as something it does cause us questions. 
	And as I mentioned, we have been through this thing and we 
	have talked about it and I have talked about how when I was 
	growing up in the 60s that, the thing was that it was going--
	we were going to be in an ice age or have a return of the 
	ice age.  And then I guess that there were some schooled 
	scientists, if you will, some of your colleagues maybe who 
	found that that was not going to be so.
	So I think it is important that we have the opportunity to 
	visit with you and find out what is an item of agreement 
	and what is not an item of agreement.  And, Dr. Mann, if I 
	could have your attention for just a few moments if you 
	don't mind, I would like to direct my question, my opening 
	question, to you.  You have said that other studies have 
	confirmed your results, but it does not appear that their 
	statistical analysis has been thoroughly examined, and I 
	wanted to know if you would be open to a review by an 
	independent team of top statisticians of climate change 
	papers before those papers get published.
	You know, I think Dr. Christy had mentioned that in some of 
	his work there were some flaws that were found.  He mentioned 
	that in his testimony and then they submitted to that.  So if 
	we are going to put government money into papers should they 
	be reviewed by others other than your social network before 
	they are published with government funds and considered to be 
	the truth?
	DR. MANN.  Well, I think there is a misunderstanding about 
	the nature of peer review as it currently exists with 
	scientific journals, and there have been some misstatements 
	along these lines in the previous comments by some of the 
	others on this panel.  For example, two of the studies that 
	have shown that the centering convention in PCA doesn't 
	make a difference in the reconstruction as shown also by 
	Dr. Gulledge were done by groups that are entirely 
	independent of me and my collaborators, von Storch and 
	Zorita.  In fact, von Storch and Zorita and I and my 
	collaborators have had vigorous disagreements in the peer 
	reviewed literature.
	So one of the studies that actually validated our approach 
	in showing that the centering convention doesn't make a 
	difference was by that group.  Another scientist at Woods 
	Hole, Peter Huybers, if I could finish that, also came up 
	with the same result so there are four different studies, 
	only one of which I was connected with that came to that 
	conclusion so the peer review process is actually working 
	quite well.
	MRS. BLACKBURN.  My question to you is do you think that 
	they should be submitted for independent review before they 
	get published?
	DR. MANN.  Well, that goes on so again it requires an 
	understanding of what the peer review process at the major 
	scientific journals actually is.  For example, with Nature 
	and Science when they receive a paper that involves both 
	statistics and climatology you can be certain that they 
	will seek out leaders in the world's scientific community 
	in all of the relevant areas before they make a decision 
	about the publication of that paper, and that is standard 
	in most of the leading journals.
	MRS. BLACKBURN.  Now let me ask you this then.  If your 
	work were submitted to an independent group and they had 
	questions or found items that needed to be changed would 
	you be willing to make those changes prior to that work 
	being published?
	DR. MANN.  Again, as I have tried to convey to this 
	committee in my earlier testimony and some of my earlier 
	responses to questions, in fact, that has been going on for 
	more than 10 years now.  My collaborators and I have been 
	re-examining the data.  Other groups have been re-examining
	the data, testing different methods, testing the methods
	with climate models simulations, figuring out which methods 
	perform well, which methods don't perform so that process 
	is ongoing.  It has been going on for more than a decade 
	now and that is how scientific progress works.
	MRS. BLACKBURN.  Thank you.  Dr. Wegman, your thoughts on 
	those questions?
	DR. WEGMAN.  Well, I think, first of all, we disagree on, 
	you know--Dr. Mann did not answer your question which was 
	if--
	MRS. BLACKBURN.  Absolutely he did not answer my question.
	DR. WEGMAN.  If you would submit to a statistical review 
	panel, would you be willing to do that.  He did not answer 
	that question.  And one of the troubling aspects of this 
	paleoclimate and the meteorological community in general 
	is that they don't have interaction with statistical 
	people even though they used statistical methods heavily.  
	We have examined this group in general as I mentioned 
	before with Mr. Stearns.  We have tried to examine this 
	to see the engagement of the meteorological community, 
	the paleoclimatology community with the statistical 
	community, and it is almost non-existent, so they are not 
	interacting with our group although they are using methods 
	that are based in the statistical literature.
	I would like to see, frankly, I would like them to be 
	engaged with us.  I think it would be a good idea.  What we 
	were trying to do in our testimony was create a path to a 
	better way of doing the science essentially saying that 
	these are two groups that should be interacting and in some 
	sense it behooves the meteorological community to be 
	interacting with us.  They are using our methods.  We are 
	not using their methods.  So I think it would be an 
	important thing to do and I--
	MRS. BLACKBURN.  Let me ask you very quickly too, I had 
	Michael Crichton's testimony that he had before the 
	Senate.  Let's see, I think this was in '05.  And he was 
	talking about having a--that government grants should 
	require a replication package which would provide some 
	transparency as part of their funding where posting that 
	package online so that saying that if it is funded with 
	government money there is no reason to exclude anyone from 
	reviewing the data that is found in research.  Is that the 
	type thing that you think would be appropriate for 
	transparency?
	DR. WEGMAN.  As I said last week in one of our conclusions, 
	basically when there is important public policy and human 
	health implications this stuff ought to be subject to 
	exceptionally more intensive review.  We drew the NIH model 
	out last time talking about the FDA and how the FDA requires 
	some statistical consultation just to that the drug issue, 
	and it seems to me that in this climate arena this has 
	incredibly important implications for society in general, 
	the world in general, and I think it ought to be carefully 
	reviewed.  The fact is Dr. Mann continues to appeal to 
	peer review but the fact is the peer review process 
	failed in the 1998 paper.
	MRS. BLACKBURN.  And you would say that was primarily 
	because it was not an independent and separate review 
	outside of that social network?
	DR. WEGMAN.  I believe that is the case.
	MRS. BLACKBURN.  Okay.  Thank you very much.  Dr. Christy, 
	let me ask you this.  There is an article we have gone to 
	a couple different times in my office, Energy, Environment 
	and Economics.  It was Dr. Soon wrote an article, Ten 
	Myths of Global Warming.  I don't know if you have seen 
	that or not.  Are you--
	DR. CHRISTY.  Sorry, ma'am.  I haven't seen it.
	MRS. BLACKBURN.  Okay.  I know there is so much here that 
	has been written.  We have killed a lot of trees using 
	all this paper, haven't we?  Okay.  And he talks about 
	showing the Medieval Warm Period, and I was going to ask 
	you to comment on this but since you have not and my time 
	has basically expired I will just let that pass.  And I 
	thank you.  Thank you, Mr. Chairman.
	MR. WHITFIELD.  Thank you.  At this time I recognize 
	Mr. Inslee for 10 minutes.
	MR. INSLEE.  Thank you.  I think this really is an amazing 
	hearing.  It is amazing because all six people at this 
	table have all agreed on the fundamental thing that this 
	Congress has got to figure out, and that is whether CO2 
	is going up, whether humans are partially responsible for 
	that, and whether that is part of the reason the Earth is 
	getting warmer.  That is the fundamental issue that 
	Congress faces.  And all six people at this table agree 
	with those propositions so I have been asking myself why 
	if we have unanimity on the fundamental question that we 
	got to ask, has Congress not done diddley to do anything 
	about this, and I think the answer is fear, because we 
	fear our inability to deal with it we blind ourselves to 
	the science.
	And I think it is a little bit like a person who is shown 
	an X-ray of their lung cancer, refusing to believe it 
	because they don't want to deal with it.  And I think that 
	is a pretty good metaphor of what is going on right 
	here.  I want to ask Dr. Cicerone, because I think he 
	represents President of the National Academy of Science, 
	how many scientists are involved in that organization, by the 
	way?
	DR. CICERONE.  About 2,000 members, but our work is done 
	largely by another 6,000 people who are chosen from 
	expertise from different fields who are non-members.
	MR. INSLEE.  So I figure there is somewhere between 6,000 
	and 8,000 scientists that you represent here today, and I 
	am impressed by that.  The consensus as I understand it 
	in the scientific community is that smoking causes lung 
	cancer on a more probable than not basis in certain 
	instances.  Is it the scientific consensus now on a more 
	probable than not basis that increasing CO2 is associated 
	with global climate change and that humans are responsible 
	for increasing CO2?
	DR. CICERONE.  Yes.
	MR. INSLEE.  So we can say that we have the same level of 
	probability in our belief as to what humans are doing to
	raise temperatures or at least that both are above 
	50 percent as we do about lung cancer, is that a fair 
	statement?
	DR. CICERONE.  I think we understand the mechanics of 
	CO2 and climate better than we do of what causes lung cancer.
	MR. INSLEE.  So here we as a country have decided to try to 
	limit and reduce the tremendous damage that is done by lung 
	cancer, but we have got as good or better science on a 
	global cancer and this Congress hasn't done a single thing
	to deal with that, and I think that is very, very 
	disturbing.  Now could I put a slide up here, please, 
	gentlemen, if we can?  I want to ask Dr. Cicerone to explain 
	something to us.
	If we look at this slide it is going to show the cyclical 
	nature--that is not actually the one I want.  Yes.  If we 
	look at this slide here it shows the cyclical nature. It 
	is from Dr. Gulledge's slides.  It will show the cyclical 
	nature going back 450,000 years ago moving forward to 
	today.  We also see CO2 going down, back up, down, back 
	up, down, back up, and we show a natural variability that 
	has occurred before the industrial age of from about 190 
	parts per million to about 290 parts per million, and I 
	think that is what Dr. Cicerone referred to as the natural 
	variability that has occurred before we started burning 
	coal, oil, gas, and wood.
	Now what I see since the industrial period I have seen 
	this vertical curve go up, and it is vertical since the 
	beginning of the industrial period, so that now we are 
	at a level, this says about 372.  I actually think it is 
	about 382 today.  And as I understand it, it is bound 
	again on about a vertical curve on this scale to levels 
	of about 550 PPM double, double the highest level of CO2 
	in pre-industrial ages back 450,000 years.
	So is my understanding of that, Dr. Cicerone, basically 
	accurate that we have an accelerated rate of CO2 that will 
	end up about twice as high carbon dioxide, which is a 
	known heat trapping gas in our atmosphere that is 
	occasioned since the dawn of the pre-industrial age?
	DR. CICERONE.  Yes, although I don't think it is necessary 
	that we will end up at double CO2.  And then also we don't 
	know for sure what happened before this time.  This is the 
	longest instrumental record we have of real data.
	MR. INSLEE.  So this is going back as far as we can with 
	real data.  We are at higher levels by about 130--excuse 
	me, more than that, about 170 parts per million, is that a 
	fair statement?
	DR. CICERONE.  Above the minimum, yes.
	MR. INSLEE.  Now the projections I have seen would suggest 
	that if we continue to spew carbon dioxide and methane into 
	the air or carbon dioxide into the air the best assessments 
	I have seen we will end about double pre-industrial levels
	by the end of the century.  Could you give us your best 
	estimate of that or comment on that at all?
	DR. CICERONE.  Oh, by the end of the century.  It depends 
	on human population.  It depends on our energy usage and 
	what technologies we are using to produce the energy so you 
	have to make assumptions about human population, how much 
	energy we will use, and what the technologies will be.  
	Double CO2 is certainly plausible.  It really depends on 
	what humans do.
	MR. INSLEE.  And it depends on what this Congress does, and 
	what Congress should do is what British Petroleum has 
	done.  British Petroleum 7 or 8 years ago decided they were 
	going to meet Kyoto targets.  Maybe it was 5 years ago.  
	And in 3 years they met their Kyoto targets in their 
	internal operations.  They reduced their CO2 as much in 
	their internal operations as the Kyoto targets would 
	require.  You know what they did?  They saved $350 million 
	in wasted energy when they decided to adopt efficiencies of 
	the type that Dr. Cicerone talked about.
	The other thing we will do is try to get these plants 
	started.  Right down the hallway here yesterday I met with 
	these guys, Iogen Corporation.  They are going to open up 
	the first cellulosic ethanol plant in southeastern Idaho.  
	When they do that, we will power our cars on E-85 
	ethanol.  We will reduce our CO2 emissions per mile by 
	80 percent or more.  They actually think it may actually 
	be negative because of some of the stuff you grow actually 
	takes carbon out of the air and puts it into the soil.  It 
	might actually be negative.
	This is the kind of thing we need to do, and we are not 
	going to do that until we come to grasp what this science 
	really is.  I want to ask--I think there is just such an 
	overwhelming consensus of--I will just read the Academy of 
	Science report.  "The IPCC's conclusion that most of the 
	observed warming of the last 50 years is likely to have 
	been due to the increase in greenhouse gas concentrations 
	accurately reflects the current thinking of the scientific 
	community on this issue."  That is a direct quote from the 
	National Academy of Science.  Now there has been some 
	issues brought about Dr. Mann's studies.  There has been 
	some questions about Dr. Christy's studies.  I frankly 
	think there are some legitimate questions about the 
	statistical assessments, and the first one Dr. Mann did, I 
	think they have been changed a little bit since then, I 
	think the same could be said for Dr. Christy, but I guess 
	the question I have, Dr. Cicerone, if Mr. and Mrs. Mann 
	had never met and we never had the services of Dr. Mann, 
	would that have varied the conclusion of the National 
	Academy of Sciences on these fundamental questions?
	DR. CICERONE.  You must be referring to his parents and 
	not his wife.
	MR. INSLEE.  I am indeed.
	DR. CICERONE.  I don't think so.
	MR. INSLEE.  And why do you say that?  In other words, if 
	Dr. Mann's work had just never appeared, and, by the way, 
	I respect it and I think it has added to the debate but if 
	his work had never occurred why do you think the Academy 
	of Science would still reach the same fundamental 
	conclusions?
	DR. CICERONE.  Because of the blending of the physical 
	evidence, the mathematical rigor and the comparisons that 
	can be made now with the predictions and the actual 
	records of the last 30 years especially.
	MR. INSLEE.  And I have a chart here, gentlemen, if you 
	can put it up here of ice core data.  I think it might be 
	the last slide on the series that I had introduced.  If 
	you have the groupings of the one that I had brought 
	today.  This is just another representation of the CO2.  
	There should be one more slide.  You are not finding it 
	right now.  Let's keep going.  Just go through these 
	quickly.  Right there.  Okay.  This is a slide basically 
	showing ice core data and we show CO2, and if I can read 
	this basically this is methane at the top, carbon dioxide 
	here, from ice core data showing these levels, only it 
	goes backwards.  These are today's dates.  This goes back 
	400,000 years.  These are today's dates showing CO2 levels 
	higher in ice core data than at any time in the last I 
	believe it is 400,000 years.  It should be 600,000 years.
	If you can, Dr. Cicerone, can you describe how that ice 
	core data work through the deuterium isotopes, if you can 
	just give us a quick description.
	DR. CICERONE.  I mentioned earlier the way the gases are 
	pulled out of these dated ice cores.  With CO2 you can do 
	it two ways.  With methane you can do it two ways.  With 
	nitros oxide you get similar results, low when it was 
	cold, high when it was warm.  The deduction of temperatures 
	at the same time depends on the different isotopes, the 
	different forms of the same chemical like carbon, the same 
	element in carbon, in this case oxygen and hydrogen where 
	because the way they evaporate a gas like water evaporates 
	differently if it has heavy hydrogen in it, deuterium, for 
	example, or oxygen 18 instead of O-16.
	We can go back and infer what the temperature was in the 
	vicinity of the ice when it formed or the snow in this case 
	which later becomes ice.  These records are pretty widely 
	used now, and under certain circumstances they are 
	absolutely the best we can do.  They are very 
	quantitative.  The statistics are clear.  There is some 
	concern over whether the temperature at which the snow 
	formed that made the ice was really a global or a 
	hemispherically average temperature or did it just reflect 
	what was happening regionally, but there you can go into 
	how much O-18 was in the oceans and the changes are big 
	enough that you can infer a pretty good geographical 
	validity of these temperature deductions as well as the 
	carbon dioxide.
	MR. INSLEE.  Thank you, and thank you all for your 
	testimony today.
	MR. WHITFIELD.  We may just have a short second round 
	here.  I am going to recognize the Chairman of the full 
	committee for 5 minutes.
	CHAIRMAN BARTON.  Yeah, and I have to go so I apologize 
	for going out of order.  This is today's USA Today 
	newspaper, the temperature map on the back.  It shows 
	the high temperature was 126 degrees Fahrenheit and the 
	low temperature was 43 degrees Fahrenheit.  That is 
	yesterday.  Is there a model in existence that can 
	replicate this with any degree of accuracy?  This is 
	yesterday's temperature.  Dr. Mann, do you have a model 
	that can do that?  This is just one country.
	DR. MANN.  I personally do not.
	CHAIRMAN BARTON.  We have got an 83 degree difference 
	on one day out of 365 days in one country.
	DR. MANN.  If I can just talk a little bit to that.
	CHAIRMAN BARTON.  I only have 4 minutes and--
	DR. MANN.  I will make it quick.
	CHAIRMAN BARTON.  Dr. Christy, you are the meteorologist, 
	I think, for Alabama.  Do you have a model that could 
	even do this in Alabama?
	DR. CHRISTY.  No, sir, we wish we did.
	CHAIRMAN BARTON.  Okay.  Now did you want to comment, 
	Dr. Cicerone?
	DR. CICERONE.  I would.  Chairman Barton, you said any 
	degree of accuracy.  That gives us some room.  The 
	British meteorological office is probably the world's 
	best.  They are in the Ministry of Defense in England. 
	Their models have pretty good predictive capability.  
	If you average over a few days and you say let's not 
	argue about the difference between San Francisco and 
	Marin County or San Antonio and El Paso.  If you average 
	over enough space in time they can hit that.  The models 
	at Penn State University are excellent.  The National 
	Weather Service can give you some degree of accuracy and 
	predictability, and they can reproduce a lot of those 
	patterns.
	CHAIRMAN BARTON.  Well, my point is, and I am not trying to 
	be cute about this, in preparing for last week's hearing I 
	read the summary and I read most of the report of the 
	National Academy of Sciences here, the National Research 
	Council.  I read Dr. Wegman's report.  And somewhere in 
	those two reports it said the data sets they use to base 
	all these models on in the whole world there are like 60 
	or less data sets.  There are just not a lot of data, and 
	we are trying to make predictions over thousands of 
	years.  Even where we have really good records for the 
	last hundred years, and some of the most advanced 
	satellites and smart people that put these computer models 
	together with hundreds of variables, we can't really 
	predict after the fact yesterday's weather with too much 
	accuracy, and yet to go to Dr. Christy's point if we 
	accept Congressman Inslee's point that we need to be in 
	solution mode a thousand nuclear power plants by themselves 
	is a trillion and a half dollars, and that will get you a 
	CO2 reduction of 10 percent.
	There are somewhere between 5,000 and 10,000 power plants in 
	this country.  Now I don't know exactly but I know there 
	are only 100--I think 112 operating nuclear plants of those 
	between 5,000 and 10,000.  And that is just one part of the 
	economy.  We have got 300 million cars and trucks.  We have 
	a lot.  I mean, it is not scientifically accurate but we have
	got a boon' doggle worth of economic consequences if we 
	really go where Mr. Inslee says we ought to be going.  And 
	I am not dogmatic about it.  I am concerned when I hear 
	Dr. Cicerone say that the parts per billion of CO2 in the 
	atmosphere is 100 parts per million higher than it ever has 
	been.
	Now that has got to give anybody pause to think, but I look 
	at all these charts and all these data sets and I can't back 
	it up, but it would certainly appear to me to be plausible, 
	to use that term again, that the Earth is always changing 
	temperature.  It is either in a warming period or a cooling 
	period.  It appears that it is a curve function.  It 
	appears that it is over the same general period of time and 
	it certainly appears that in the last 100 years that the 
	upward curve has accelerated at a more rapid rate than say 
	a thousand years ago.  But it is not clear what, if 
	anything, we can do to change that basic system.  And so 
	before we go off the deep end I really do want to make sure 
	that these models are independently reviewed and really are 
	scientifically accurate and really can be replicated.  And 
	I really do want to know what the confidence levels are.  
	We are going to get to problem solution, and we are going 
	to have a huge debate about that.  But since we can't even 
	predict with much accuracy what yesterday's temperature was, 
	it is a little bit much to ask us to make multi-trillion 
	dollar decisions on models that 10 years ago when Dr. Mann 
	put out his report, he was the first one, and even today 
	most of the people that are doing the modeling are some 
	part of his network, which is not a bad thing.  It shows you 
	operate with a lot of smart people that care a lot about 
	the environment.
	But it doesn't mean that the United States government 
	makes trillion dollar changes in public policy until we 
	get a little bit more information about that, and that is 
	why we are doing these hearings.  And so I apologize for 
	going another minute over but I thank you, Mr. Chairman, 
	for holding this, and I thank the members, Mr. Inslee and 
	Mr. Stupak and Mrs. Blackburn for being here.  I wish every 
	member of the Oversight Subcommittee was here.  I wish we 
	had more intensity on this so that we could get more 
	involved.  Thank you, Mr. Chairman.
	MR. WHITFIELD.  Thank you.  Dr. Mann, did you want to make 
	a comment?
	DR. MANN.  I just wanted to clarify a distinction here in 
	this discussion.  On the one hand we are talking about 
	weather, and that is the day-to-day fluctuations and the 
	character of the atmosphere, and in the other cases we are 
	talking about climate and there is a very important 
	distinction between the two.  Climate is the statistics, 
	the long-term statistics of the weather, and there are 
	certain things that we can say very well about climate.
	CHAIRMAN BARTON.  But your model is predicting temperature 
	change.
	DR. MANN.  It is not a model.
	CHAIRMAN BARTON.  That may be the variable but that is the 
	variable, and we are talking about catastrophic consequences 
	with 3 to 4 degree Fahrenheit changes.
	DR. MANN.  That is the point.  It is not a model.  A model 
	is a set of numerical equations that we try to solve the 
	equations that describe the atmosphere and the ocean.  Our 
	reconstructions aren't that.  They are not a model.  The 
	models are a completely different thing, and there are 
	weather forecasting models as well as climate models, and in 
	certain things the climate models are quite good.  We are 
	doing very well now in predicting El Ninos.
	CHAIRMAN BARTON.  What term should I be using?  Not model.  
	Program, algorithm?
	DR. MANN.  They are statistical reconstructions and data and 
	then there are the models, and I just wanted to make that 
	distinction.
	CHAIRMAN BARTON.  I stand corrected.
	MR. WHITFIELD.  I just have one other question I would like 
	to ask because we have heard a lot today about core samples, 
	and I have been sort of interested in this chart that 
	Mr. Inslee brought in showing CO2 concentrations and from 
	that extrapolating temperatures.  And I would just ask Mann 
	and Christy and Cicerone once again, I didn't really ask 
	this question before, but I would like for you to tell us 
	the facts about the reliability of the ice core samples.  
	And we have heard a lot of comments about using that to 
	determine CO2 and then the question is using ice core 
	samples as historical thermometers.  Can they really be 
	considered accurate thermometers.  Can you take those 
	CO2 levels from ice cores and extrapolate in an accurate 
	way?
	DR. MANN.  I will take the first stab at that.  There are 
	certain physical processes and there are basic physical 
	processes that control the ratio of different isotopes, 
	of oxygen in the ice, the water that is in solid form, it 
	is ice trapped in those ice cores, and so it is on a 
	somewhat different footing from some of the other sorts 
	of proxies like tree rings that we use where we are 
	relying on some biological relationship.
	In the case of ice core isotopes it is really physics.  
	It is physics that is controlling the ratio of the different 
	isotopes of oxygen and that is telling us something about 
	the sea surface temperatures when the water evaporated from 
	the ocean because the ice that is deposited at some point 
	had to evaporate from the ocean surface.  It also tells us 
	something about the local conditions when the ice was 
	deposited.  Both the evaporation and the deposition depend--
	they influence the ratio of those isotopes.
	DR. CHRISTY.  Just in terms of the temperatures, reproducing 
	temperatures from them?
	MR. WHITFIELD.  Yes.
	DR. CHRISTY.  The closer you get to the poles, the better the 
	temperature relationship is.  I think in the NAS report we 
	show six tropical and Tibetan ice cores and they are all 
	different.  All six of them are different.  But the closer 
	you get to the poles the relationship looks a lot better 
	there.
	MR. WHITFIELD.  Okay.  Do you have anything to add, 
	Dr. Cicerone?  Okay.  Yes.  Mr. Waxman had asked we enter 
	into the record the remote sensing system letter which we 
	will do and you asked about the interface stewardship 
	alliance which we will do.  And then we are going to keep the 
	record open for 30 days.  And does anyone else have any 
	comments?
	MR. STUPAK.  If I may, Mr. Chairman.  We were talking 
	earlier, I was going to start off my questioning and we were 
	talking about the Fortran, and I was joking with the 
	Chairman so I forgot to ask these questions.  Dr. Wegman, 
	in your report you state that, and I am quoting now, "We 
	judge that the sharing of research materials data and results 
	by Dr. Mann was haphazardly and grudgingly done."  You also 
	go on to state that Dr. Mann--you had trouble reading 
	Dr. Mann's code in part because it was in Fortran and that 
	you had trouble understanding some of the data that 
	Dr. Mann used.
	Did you or your co-authors contact Mr. McIntyre and get his 
	help in replicating his work?
	DR. WEGMAN.  Actually, no.  What I did do was I called 
	Mr. McIntyre and said that when we downloaded his code we 
	could not get it to work either, and it was unfortunate that 
	he was criticizing Dr. Mann when in fact he was in exactly 
	the same situation.  Subsequently, he reposted his code to 
	make it more user friendly and we did download it 
	subsequently and verified that it would work.
	MR. STUPAK.  And then after you re-downloaded and verified 
	it worked, did you have any further contact with 
	Mr. McIntyre then?
	DR. WEGMAN.  Well, as I testified last week, Dr. Said and 
	myself had gone to one of the meetings where he was talking, 
	and we spoke with him but did not identify who we were at 
	the time.  This was early in the phase.  Subsequently, I had 
	had no contact with him until basically last week.
	MR. STUPAK.  Okay.  Any of your co-authors that you know of, 
	Dr. Said or any others, have contact with Mr. McIntyre other 
	than that one time at this convention or wherever he was 
	speaking?
	DR. WEGMAN.  One of my graduate students, John Rigsby, who 
	did the code for us, worked the code for us, did have some 
	interaction with him in order to verify some of the details 
	of the code.
	MR. STUPAK.  So you, Dr. Said and this Mr. Rigsby would be 
	the people who had contact with Mr. McIntyre then?
	DR. WEGMAN.  That is correct, yes.
	MR. STUPAK.  Thank you.  Nothing further.
	MR. WHITFIELD.  Mr. Inslee, do you have any--
	MR. INSLEE.  I just want to comment in response to Chairman 
	Barton's comment about the 1,000 or 10,000 nuclear plants 
	he posited might be necessary.  I really--and I don't want 
	to get in debate about nuclear but I am really much more 
	optimistic about that, and the reason I say that is that we 
	have been so successful in improving the efficiency of our 
	economy because of the intellectual capital of men and women 
	like you who have helped us develop technologies to be much 
	more efficient.  Let me give you an example.
	We actually per unit of gross domestic product use almost 
	half as much energy as we did in 1973.  You think about 
	that.  Since 1973 our economy produces twice as much 
	domestic product with the same amount of energy that it did 
	in 1973, and there is just no reason on this green Earth 
	that all of a sudden we got stupid, that we are not going 
	to be able to continue as the most brilliant society on 
	Earth and innovation to continue those efficiency 
	innovations.
	And they are not rocket science.  Three of my neighbors 
	drive cars that have already reduced their transportation 
	related CO2 by 50 percent.  The Chairman talked about the 
	need to reduce our emissions by 40 percent to meet Kyoto. 
	Three of my neighbors and myself, I may add, have already
	reduced ours by 50 percent in our transportation sector. 
	Simple.  They are on the lots today.  This is no new 
	technology.  So I just want to say in partial closing 
	that I am a person, as my comments have indicated, who
	believe this is a major challenge for us and that we have 
	to act, and it is well past the date where we need to 
	move to solutions rather than debating the problem.
	But I also believe that I am an optimist because I totally 
	believe it is in the human--it is capable because of our 
	intellectual ability to invent our way out of this 
	pickle.  And those who are people of great faith, because 
	the faith community is now becoming engaged in this debate, 
	because we are stewards of God's creation, and they are 
	starting to urge Congress to act as well.  We also ought 
	to be optimists and believe we can do it.
	And I got to tell you, in the last 3 weeks I have met five 
	people, one in cellulosic ethanol, one in wave power, one 
	in efficiency in cars, one in efficiency in airplanes the 
	Boeing 787 we are building in Seattle is going to get 
	20 percent better fuel mileage than their last model.  
	These are the kind of things that America is going to do 
	when we tackle this.  So I just hope that this is a first 
	step toward moving just one quick question, Dr. Cicerone. 
	I have heard there has been some new evidence about 
	finding large amounts of energy in the ocean that has 
	suggested that this is sort of new research to indicate 
	in the last 12 months.  Is this something I am dreaming or 
	is there new research in that regard?
	DR. CICERONE.  Maybe methane clath rates would be the only 
	thing I am--
	MR. INSLEE.  I am sorry.  What I mean is as far as we found 
	temperature increases in the oceans that have--
	DR. CICERONE.  Oh, yeah.  The result was reported about a 
	year and a half ago about over the last 40 or 45 years the 
	oceans, the upper 700 meters or so have warmed up, and I 
	summarize it very briefly in my testimony, yes.
	MR. INSLEE.  And I will put in the record a study called 
	Penetration of Human-Induced Warming into the World's 
	Oceans.  It is published in Science in July, 2005.  Many 
	people thought this was sort of the nail in the coffin of 
	skeptics about global warming.  And again thank you for 
	your testimony.
[The information follows:]
	DR. GULLEDGE.  Mr. Inslee, if I may just may make a 
	comment.  Also regarding Mr. Barton's comments, I realize 
	he is gone.  I am also from Texas and I use scientific terms 
	from down there.  There are whole passels of money to be 
	made on alternative energy, and it is not just about being 
	expensive.  Also, there are real serious costs to inaction 
	that have not been figured into this equation here.
	MR. INSLEE.  And I just want to compliment the Chairman's 
	humor about this.  As I was walking off the field at the 
	baseball game this year and he was at third base, and I 
	just pulled my hamstring.  As I was walking by he says, 
	well, Inslee, I suppose that was because of global warming 
	too.  So he has a great finely tuned sense of humor and we 
	will look forward to using it as the debate goes on.  
	Thank you.
	MR. WHITFIELD.  Thank you, Mr. Inslee.  I would like to 
	stipulate that in my district we just opened up two new 
	ethanol plants as well.  So I want to thank you all very 
	much for your patience.  We got documents to enter here.
	MR. STUPAK.  Mr. Chairman, that is a request to put in an 
	abstract of an article.  I would suggest we just get the 
	whole article, put it in there, and then we have the 
	complete article for everyone to see.
	MR. WHITFIELD.  Okay.  Without objection.
	MR. STUPAK.  That can serve as a place holder until I get 
	the whole article.
	MR. WHITFIELD.  So ordered.  And then we will keep the 
	record open.  Mr. Inslee.
	[The information follows:]



	
MR. INSLEE.  Mr. Chairman, I would like to submit an essay.  It is 
published in Science called the Scientific Consensus of Climate 
Change.  It relates to that 928 papers as well as the article I 
ust made reference to.  Thank you.
	MR. WHITFIELD.  Okay.  Without objection.  And we will 
	keep the record open for 30 days.
	[The information follows:]



	MR. WHITFIELD.  Thank you all again for your testimony.  We 
	look forward to working with you as we move forward.  That 
	concludes today's hearing.
	[Whereupon, at 6:48 p.m., the subcommittee was adjourned.]


RESPONSE FOR THE RECORD OF DR. MICHAEL E. MANN, ASSOCIATE PROFESSOR 
AND DIRECTOR, EARTH SYSTEM SCIENCE CENTER


Question No. 1.  I understand that although your current practice 
is to make your computer code available publicly, many researchers 
in your field do not do so. Although computer code may not have 
commercial value, why would a researcher not want to release his 
code?

Answer:  
	This is a question that my colleagues and I have wrestled 
	with over the years.  As the question acknowledges, for the 
	past five years or more, my colleagues and I have made 
	public our computer codes, just as we made public our code 
	for the 1998 study last year.   Our decision to make our 
	code public comes at a time when there is increased 
	standardization in codes, and the need to tailor codes to 
	accommodate the various and often idiosyncratic computer 
	systems that were used in the 1990s has diminished.  But 
	even today, many, perhaps most, climate scientists do not 
	share their codes.  In my view, there are legitimate 
	reasons for reaching that decision, even though it is not 
	the decision my colleagues and I have made. 
	For one thing, most code is written to enable scientists 
	to perform specific functions, and thus code is generally 
	written in a form of short-hand that is not easily 
	understood by others.  To make code usable by other 
	researchers, the code writer has to undertake significant 
	additional work, in the form of documentation, testing for 
	potential platform dependence, tidying, and so forth, that 
	places a significant burden on the code writer.  Many 
	scientists do not think that undertaking that additional 
	burden is worth it.  
	Second, access to computer codes is not necessary to 
	replicate a study.  I realize that some of my critics have 
	argued otherwise, but it is just not the case that 
	scientists need access to computer codes to replicate 
	studies.  As I tried to make clear in my testimony before 
	the Committee, a study may be replicated if the scientists 
	conducting the initial study make available both the 
	underlying research data and an algorithm that gives a 
	step-by-step account of how that data was analyzed.  As my 
	testimony pointed out, the 1998 and 1999 work by my 
	colleagues and me was recently replicated by a team of 
	scientists (Wahl and Ammann) who did not have access to our 
	codes, but who were able to replicate our work without 
	difficulty.  So replication does not depend on access to 
	computer codes.
	Moreover, scientists, like entrepreneurs, corporations, and 
	others engaged in the production of intellectual capital, 
	are competitive, and rightly so.  Competition in the 
	marketplace of ideas is what science is all about.  We would 
	all like to make our greatest possible contributions to 
	advancing the forefront of our scientific disciplines.  
	Indeed, we are rewarded (in terms of grants, promotions, 
	academic recognition, and do forth) in proportion to the
	contributions we make in the advancement of science.  Asking 
	scientists to release their codes before they have had an 
	opportunity to apply them to a number of potential 
	interesting problems is asking them to sacrifice their 
	competitive advantage. This would be no different than 
	asking Microsoft to release the code for its latest 
	operating system as soon as it reaches the market.  Microsoft
	is not about to do that, and most people would consider a 
	requirement that Microsoft freely dispense its intellectual 
	property --- its codes --- as antithetical to the principles 
	of a free market.  The argument is no different in the case 
	of scientists and their computer codes or other tools of 
	their trade.

Question No. 2.  Dr. Wegman states that paleoclimatologists do not 
interact with statisticians.  Do you have any response to that 
statement? What steps, if any, is the paleoclimatology field taking 
to ensure that it is using appropriate statistical methodologies?
Answer:
	Unfortunately, Dr. Wegman made this claim without engaging 
	in any effort to ascertain the extent to which climate 
	scientists interact with statisticians.  To the contrary, 
	Dr. Wegman simply assumed --- without data, indeed, without 
	any basis at all --- that climate scientists, and 
	paleoclimatologists in particular, do not interact with 
	statisticians. 
	Dr. Wegman's accusation could not be further from the truth. 
	The participation of statisticians in climate science has 
	become so routine that there is an entire field of climate 
	research known as "statistical climatology," which involves 
	the collaboration of large numbers of statisticians and 
	climate scientists.  There are even textbooks dedicated to 
	the study of statistical climatology.  In his testimony 
	before the Committee, Dr. Hans Von Storch found it necessary 
	to inform Dr. Wegman of this fact.  And Dr. Von Storch 
	should know; he and Dr.  Francis Zwiers (a Ph.D. statistician 
	specializing in climate applications) have written one widely
	used textbook on statistics and its applications to climate 
	studies.  Another statistician, Professor Dan Wilks of 
	Cornell University, has written an additional textbook on 
	statistics and its applications to the atmospheric sciences.   
	The extensive collaboration between climate scientists and 
	statisticians is also reflected in the academic literature. 
	Hundreds of papers have been published in the climate and 
	paleoclimate literature involving the collaboration of 
	statisticians and climate scientists.   These are all 
	publicly available and could have been identified by 
	Dr. Wegman in a few hours of research.  Two members of the 
	NRC committee that reviewed paleoclimate reconstructions 
	in its recent report (Dr. Douglas Nychka and Dr. Peter 
	Bloomfield) are statisticians (both of their doctorates are 
	in statistics) who have published in the climate literature
	and who have actively collaborated with climate scientists.
Had Dr. Wegman bothered to make even the slightest inquiry, he would 
have found that there are in fact many statisticians (that is, 
individuals with doctorates in statistics) who have been and remain 
active members of the community of researchers in the areas of 
atmospheric science and climate research.  Even a cursory review of 
the structure of our community reveals this readily.  I have been 
informed that many of my statistical climatologist colleagues are 
deeply offended by Dr. Wegman's unfounded pronouncements to this 
Committee, pronouncements which effectively deny their contribution 
to the advancement of science.  
	Moreover, the American Meteorological Society --- the 
	leading professional organization of atmospheric 
	scientists --- has a Committee on Probability and 
	Statistics, and members of the committee are drawn from 
	both atmospheric/ocean/climate scientists and 
	statisticians.  I was a member of that committee for a 
	3-year term (2003-2005) that recently ended.  The 
	committee's website can be found here:
http://www.isse.ucar.edu/ams/ams_ps.html, and the committee 
members' biographies are available here:
http://www.isse.ucar.edu/ams/ams_ps.html#members.   The chair of 
the committee, Dr. Rick Katz is a statistician (with his
doctorate in statistics from Penn State University) and senior 
scientist at NCAR.  Other statisticians on the committee include 
Dr. Tilmann Gneiting (Department of Statistics, University of 
Washington), and Dr. William Briggs (Adjunct Assistant Professor of 
Statistical Science, Cornell University). These statisticians are 
active members of the climate research community.
	Equally important, one of the primary centers for climate 
	research in the U.S., NCAR, has maintained a thriving 
	Geophysical Statistics Project ("GSP"), which was founded 
	more than a decade ago. This program has been funded by 
	the National Science Foundation's Division of Mathematical 
	Sciences, which has recognized for some time the importance 
	of encouraging statisticians to collaborate actively with 
	atmospheric scientists/climate scientists.   I participated 
	as a graduate student in GSP's inaugural workshop in 1994.  
	Many leading statisticians (e.g., Dr. Grace Wahba, 
	Dr. Arthur Dempster, and Dr. Noal Cressie) were 
	participants.  The GSP has since thrived, providing an 
	important opportunity for collaboration between 
	statisticians and climate researchers.  More information 
	can be found at the GSP webpage: http://www.image.ucar.edu/GSP/.   
	It bears noting that the project has now produced more than 
	two dozen Ph.D. statisticians who have become active 
	researchers in the atmospheric, oceanographic, and 
	climate sciences.  Its members and visitors have included 
	dozens of statisticians who have worked collaboratively
	with atmospheric scientists and climate researchers. The 
	leader of the project, Dr. Douglass Nychka, was one of 
	the members of the aforementioned NRC panel.  He was also 
	a consultant in the recent paper by Wahl and Ammann that
	refutes the oft-cited criticisms of the Mann et al. work 
	by McIntyre and McKitrick.

Question No. 3. Dr. Wegman has hypothesized that the peer review 
process failed and allowed publication of your 1998 and 1999 
studies without adequate vetting of the study.  This was based in
part on his social network analysis that showed you have 
connections with 42 other authors in paleoclimatology.  Of the 
42 co-authors identified by Dr. Wegman, how many of them were 
co-authors with you in or before 1999?

Answer:
	Dr. Wegman's accusations are so riddled with flaws that 
	it's hard to know where to begin in response.  But let me
	first address the specious accusation by Wegman that the 
	peer-review process somehow "failed" with respect to our 
	'98 and '99 studies.  It is bewildering that Dr. Wegman 
	(who has no expertise in the area of atmospheric 
	science/climate, and indeed was wholly unable to correctly 
	answer some of the most basic questions about climate 
	science during the hearings) would characterize the 
	publication of our work as a "failure."   One would 
	assume that an academic would avoid rendering judgments 
	in fields in which he is demonstrably unknowledgeable.  
	Certainly the scientific community has reached the 
	precisely the opposite conclusion.  Our 1998 and 1999 
	studies are widely cited, and the conclusions stated in 
	them have been repeatedly reaffirmed.   Just one example 
	of the scientific support for these works should 
	suffice:  The National Research Council panel in their 
	recent Report characterized our study as 
	"groundbreaking", and the panel concluded that its key 
	conclusions have held up over nearly a decade of 
	exhaustive and independent follow-up research.  That is
	a pretty good track record by any standard.  Thus, 
	judged by experts who understand climate studies, 
	Wegman's efforts to disparage our work as "failed" are 
	nothing short of silly.  
	Let me next address Wegman's equally specious and 
	unsupported claim that scientists who work in a given 
	field cannot objectively review the work of their
	colleagues and competitors in that field.  By way of 
	illustration, I have attached (as Attachment 1 to these 
	Responses) the famous 1927 photograph of attendees of the 
	Solvay Physics meeting in Brussels.  It shows a group of 
	29 physicists engaged in a collegial, small conference.  
	Virtually every attendee was a driving figure behind our 
	understanding of modern physics.  Appearing in the photograph 
	are Einstein, Heisenberg, Bohr, Fermi, Dirac, de Broglie, 
	Born, Pauli, Langmuir, Planck, Curie, Compton, Ehrenfest, 
	Lengevin, and others of equal prominence.  The members of this
	group all knew each other, worked with each other, 
	collaborated on research with one another, visited each other,
	went mountain-climbing together, and so forth.  Familiarity 
	did not compromise their contributions to science.  While I 
	do not claim that the group I collaborate with is likely to 
	duplicate the feats of the scientists who gathered in Brussels 
	80 years ago, the point remains --- scientific collaboration 
	does not turn scientists into timid lapdogs unwilling to 
	criticize the work of their colleagues.   
	Let me turn now to the specifics of the question.  It is 
	baffling how Dr. Wegman arrived at the number (42) he used to 
	describe my co-authors.  One would think that a statistician 
	could do simple arithmetic.  My curricular vitae (CV) is 
	available on the internet, and it is clear that Wegman consulted
	it (but not me) in the preparation of his paper.  Nonetheless,
	none of the numbers he uses add up.  Part of the problem may 
	stem from Wegman's ill-advised effort to distinguish between
	authors engaged in "paleoclimatology" and "climatology," since
	most climate researchers have worked, in some manner, on some
	aspect of paleoclimate.   So the distinction he attempts to 
	draw between "paleoclimatologists" and "climatologists" is 
	illusory at best.  This too underscores the hazards of an
	amateur seeking to draw conclusions in a field in which he
	has no expertise.    
	But to answer the question Wegman poses, let us consider the 
	correct numbers (see Attachment 2 to these Reponses) which 
	are based on all of my peer-reviewed journal publications as 
	listed on my CV (and not including "gray literature" such as 
	book chapters, encyclopedia pieces, reports, conference 
	proceedings, letters to editors, opinion pieces).  I published 
	with 10 co-authors prior to 1993 based on my undergraduate 
	research in solid state physics.  These publications are 
	unrelated to climate research, and are not included. 
	So let us consider just my climate-related papers (i.e., post 
	1993), as Wegman purports to do.   In climate research, I had
	14 co-authors through the year 1999.  I had 101 co-authors
	through the end of 2005.   So Wegman's calculations, based on
	42 co-authors, are off-base by more than a factor of two.  
	Wegman also appears to have made even more fundamental errors 
	in his review of the science (a point I address below).   
	But I believe the question goes to how influential I was in 
	the field, in a relative sense, at the time of publication of
	my '98 and '99 studies.   After all, Wegman claims that there
	is, in essence, an almost sinister conspiracy of like-minded
	climate scientists who act as a cartel to control the published
	literature in climate studies.  And his "proof" is the fact 
	that I have published with many prominent scientists who, in 
	Wegman's view, would be unwilling to criticize my 1998 and 1999
	work even if it were seriously flawed.  But this theory does 
	not wash.  Apart from the fact that even my closest 
	collaborators are perfectly willing to criticize my work when
	they think it is flawed, Wegman's math just does not support 
	his theory.  As indicated above, the vast majority (86%) of 
	my co-authorships occurred after my 1998/1999 studies.  So 
	Wegman's effort to suggest that I was influential in the 
	field at the time these studies were published, or in the 
	aftermath of their publication, cannot be squared with the 
	data, and is, in fact, nothing short of absurd.  

Question No. 4.  Does the scientific community rely exclusively or 
primarily on the peer review process conducted before an article
is published to test the robustness and validity of new scientific 
discoveries or theories? Or does the development of science depend
on an iterative process that involves not only peer review before 
publication, but also review and competing research and analysis 
by other scientists after publication?
	
Answer: 
	This question raises an important issue that was 
	unfortunately not adequately aired at the hearing.  
	Dr. Wegman and others have expressed the view that the 
	scientific community somehow places exclusive reliance on
	the peer review process as the determinant of scientific 
	truth.  But the peer review process is hardly the only, let
	alone most important, way that the scientific community 
	tests the accuracy and reliability of scientific papers. 
	Indeed, Wegman's contention reflects a fundamental lack of
	understanding of the basic principles that govern the 
	scientific discipline.  Science progresses through an 
	open, self-correcting process whereby scientists place 
	their ideas in the marketplace, typically by publishing 
	articles in peer review journals.  The peer review process 
	ensures only that basic mistakes are not made, that the 
	article acknowledges the existing literature on the subject,
	and that it contributes in some way to the exploration of
	important scientific issues.  But peer review does not and
	cannot vouch for the accuracy of the paper.  That is the 
	function of the scientific process, by which other scientists 
	test out and question the work of their peers.  Some ideas
	stand the test of time; others do not.  Copernicus was proven
	right over time; Ptolemy's conception that the Earth forms 
	the center of the universe was proven wrong.   Much of 
	Einstein's work has stood up to reevaluation, but some of 
	his theories have been proven to be incorrect as well.  
	It is relevant in this context to again emphasize that the 
	key conclusion that my colleagues and I drew tentatively in 
	our work in the late '90s --- that late 20th century Northern 
	Hemisphere average warmth was likely unprecedented in at least
	the past 1000 years --- has held up for more than a decade, 
	after dozens of independent studies have reexamined that
	claim.  So it has passed this important test of time.  The 
	peer-review process is simply a quality control process to 
	make sure that claims, theories, and ideas that are self-
	evidently flawed from the beginning do not clutter the pages 
	of the legitimate peer-reviewed scientific journals, that is,
	to ensure that published papers have potential merit.  Peer 
	review is a simple first step at quality control.  It does 
	not, nor should it, be considered evidence that the 
	conclusions of a particular published paper are accurate or 
	not.  No single paper should ever be used to establish the 
	validity of a particular hypothesis or conclusion.  The
	accuracy of claims, hypotheses, conclusions, indeed theories, 
	can only be established by examining the collective body of 
	peer-reviewed research to date on any particular topic, and 
	the overall thrust of that body of research.  Indeed, the 
	importance of broad-based scientific assessments (such as 
	those provided by the Intergovernmental Panel on Climate 
	Change or "IPCC") is to evaluate the entire body of peer-
	reviewed literature on a particular topic and to determine 
	the consensus, if there is one, that emerges in that body 
	of literature. 

Question No.  5.  Should all scientific papers be withheld from 
publication until the results are independently replicated?
	
Answer: 
	This question also raises an important issue that was not 
	adequately aired at the hearing.   Once again, Dr. Wegman 
	and others suggested at the hearing that scientific pa
	pers 
	be shelved for the time it takes for the results to be
	verified independently.  This view is misguided, and, if
	followed, would seriously undermine the development of 
	scientific knowledge.   It takes considerable time to 
	replicate a study.  Meanwhile, important findings that 
	would be unavailable to other scholars.  Such a requirement
	would dangerously slow the progress of science.  
	As I explained above, in my view development of scientific 
	knowledge can take place only through an open, self-
	correcting process whereby scientists put out ideas, other
	scientists test them, and those ideas which stand up to 
	future tests survive while those that do not are ultimately 
	rejected.  It is important in this context that ideas with
	potential merit be placed in the scientific discourse in a 
	timely manner, so that they can be followed up in a timely
	manner by the entire scientific community and not just a few 
	researchers engaged in replication, and the scientific 
	process can proceed at an appropriate pace.  Were the 
	suggested requirement to be followed where all papers 
	required independent replication before publication, this 
	would bog down the scientific process to a near standstill.  
In data-poor areas of science such as paleoclimatology, the added 
benefit of new data is much more valuable than the pure replication 
of a past study.  "Replication" in a pure sense provides very poor 
value for money.  A good example would be the now- famous GRIP and 
GISP2 ice cores from Greenland.  These are two different Greenland
ice cores that were drilled at two nearby but distinct locations
by two different (one U.S. and one European) teams.  Had the total 
available funding simply been used for both teams to drill cores 
at the same site, and thereby replicate each other's work, only the
technical accuracy of the coring would have been validated.  
Instead, the reproduction of a record that was nearby but separate 
gave both support to the main results, but also allowed the groups 
to discover a mix-up in dating prior to 100,000 years ago in one
of the two cores.  So drilling two different ice cores, rather than
drilling from the same source twice, proved to be a far more 
valuable use of the available funding and resources.
	The proponents of this idea also ignore the near-
	impossibility of its implementation.  How would scientists
	be persuaded to replicate the unpublished work of others?
	What would their incentives be to conduct this work quickly,
	especially if it meant sacrificing the time researchers
	would prefer to spend on their own work?  Would every study
	be subject to replication?  Or only important studies?  And
	who would decide which studies required replication prior to 
	publication?  Who would pay for these replications?  Would 
	the government pay for them?  Is Congress prepared to double 
	the size of research budgets for all of the major scientific
	funding agencies (e.g. NSF, NIH, NOAA, etc.)?  And these 
	practical problems are only the tip of the iceberg.
	My essential plea here is that Congress should not fix that 
	which is not broken.  Since Copernicus' time the scientific
	process has successfully weeded out the wheat from the 
	chaff.    It would be dangerous for Congress or any 
	government body to tamper with that process.
	There is another element of this question which raises a 
	deeply troubling matter with regard to Dr. Wegman's 
	failure to subject his work to peer review, and Wegman's 
	apparent refusal to let other scientists try to replicate
	his work.   Professor David Ritson, Emeritus Professor of
	Physics, Stanford University, has found error in the way 
	that Dr. Wegman models the "persistence" of climate proxy
	data.  Interestingly, this is the same error Steven 
	McIntyre committed in his work, which was recently refuted 
	in the paper by Wahl and Ammann, which was in turn vetted
	by Dr. Douglass Nychka, an eminent statistician.  
	Dr. Ritson has determined that that the calculations that 
	underlie the conclusions that Dr. Wegman advanced in his 
	report are likely flawed.  Although Dr. Ritson has been 
	unable to reproduce, even qualitatively, the results 
	claimed by Dr. Wegman, he has been able to isolate the 
	likely source of Wegman's errors.  What is so troubling is
	that Dr. Wegman and his co-authors have ignored repeated 
	collegial inquiries by Dr. Ritson and apparently are 
	refusing to provide any basic details about the 
	calculations for the report (see Attachments 3 and 4 to 
	this Response).   It would appear that Dr. Wegman has 
	completely failed to live up to the very standards he 
	has publicly demanded of others.
	Moreover, the errors that Dr. Ritson has identified in 
	Dr. Wegman's calculations appear so basic that they would 
	almost certainly have been detected in a standard peer
	review.   In other words, had Dr. Wegman's report been 
	properly peer-reviewed in a rigorous process where peer-
	reviewers were selected anonymously, it likely would not
	have seen the light of day.   Dr. Wegman has thus 
	unwittingly provided us with a prime example of the 
	importance of the peer review process as a basic first 
	step in quality control.


RESPONSE FOR THE RECORD OF DR. JOHN R. CHRISTY, PROFESSOR AND 
DIRECTOR, EARTH SYSTEM SCIENCE CENTER, NSSTC, UNIVERSITY OF 
ALABAMA IN HUNTSVILLE


28 August 2006


Hon. Ed Whitfield
Chairman
Subcommittee on Oversight and Investigations
Committee on Energy and Commerce
2125 Rayburn House Office Building
Washington DC  20515-6115

Dear Rep. Whitfield,

Thank you for the opportunity to appear before your Subcommittee 
to address issues of global climate change.  I especially thank 
you for the opportunity to clarify some of the material that was 
entered into the official record which appeared to contradict my
testimony.  I assure you that what I presented was accurate as 
to my experiences and understanding of climate change in general
and dataset construction in particular.

I will be happy and available to answer any further questions 
regarding my appearance.


Sincerely,




John R. Christy
Director, Earth System Science Center
Alabama State Climatologist
University of Alabama in Huntsville


Questions from Rep. Whitfield for John R. Christy

(1) During the hearing, Mr. Waxman introduced into the hearing 
record a letter from Frank J. Wentz regarding your sharing of
code with Remote Sensing Systems 9RSS).  Please explain your 
interactions with RSS (and Mr. Wentz) and subsequent interactions 
with Dr. Mann, as mentioned in your testimony.

(1) Answer

In the Hearing before the Subcommittee on Oversight and 
Investigations of the House Committee on Energy and Commerce on 
27 July 2006, I testified about our cooperation with Remote 
Sensing Systems (RSS) regarding sharing of satellite data and 
code.
Mr. Waxman introduced into the record a letter from Mr. Frank 
Wentz of RSS which included an email from me to Mr. Wentz, over 
4 years old, implying an apparent lack of cooperation.  The 
problems here are (a) that this March 2002 email to Mr. Wentz 
from me was simply the first in a long series of emails in 
which we indeed cooperated, and (b) that this exchange related
to a different dataset than the one I was speaking of in my
testimony.  The following discussion describes the way these 
two datasets were examined by RSS.

Mid-Tropospheric (MT) Temperature Product
Another RSS Scientist, Dr. Carl Mears (not Dr. Mann), began 
constructing an MT product from the raw microwave digital 
counts in early 2002, following much of our published 
methodology.  There were some discrepancies between our two 
results.  Mr. Wentz asked for the code with which we 
constructed our MT data so as to resolve these differences.  
As stated in my first email on the subject, shared by 
Mr. Waxman in Mr. Wentz's letter, I declined to send the code
for the reasons given.  However, there were many further 
exchanges of information (in terms of the Hearing language: 
there were discussions about the "algorithms") to the point 
that RSS understood the three main differences between our
two datasets.  Mr. Wentz's description of "trial and error" 
in his letter in this process left out the important point 
that we were in constant communication on the details and 
subtleties of the dataset construction process.  
During this time, we discussed at great length matters 
concerning (1) the methodology of calculating the strength
of the target-temperature effect, (2) the methodology of 
determining intersatellite biases and to a lesser extent (3) 
the adjustments for the satellites' east-west drifting 
(diurnal effect.)  
At a conference in Asheville NC, (Oct. 2003) Dr. Mears 
presented a talk entitled "Understanding the difference
between the UAH and RSS retrievals of satellite-based 
tropospheric temperature estimate" and stated he was 
satisfied as to having understood the main reasons for the
differences between our two datasets.  Indeed in this 
presentation, Dr. Mears used some of the adjustment files 
we had provided to them to help answer questions of how our
adjustment process worked (i.e. diurnal drift files.)  He 
also displayed our target factor calculations, again provided 
to RSS, along with a detailed description of their 
computation.  It was clear we had provided information to 
understand the discrepancies.
RSS was also able to publish these findings and results 
(Mears et al. 2003).  I was a reviewer of that paper and 
recommended publication. In my view, this closed the episode 
on this dataset.  

Lower Tropospheric (LT) Temperature Product
In 2005, Dr. Mears also led in the development of a different
temperature product, LT, which UAH had been producing since 
1992.   He addressed the issues of hot target calibration
coefficients and intersatellite biases to his satisfaction but
was unable to replicate our diurnal effect.  He asked for more 
information and we supplied the appropriate section of the 
code and intermediate adjustment files so he could test the 
code against the output.  With these in hand he was able to
discover the artifact in the algebra which created the error
most visible in the tropics.  
That we supplied these items is inarguable as the paper 
published by Mears and Wentz (2005) in Science displays the 
UAH adjustment files.  Additionally, even though we did not 
know the outcome of their study at the time, I granted 
permission to publish our files as shown by this following 
exchange between Dr. Mears and myself on 13 May 2005 in which
he responds to me for being open in this way.

13 May 2005  8:41 p.m.

Hi Carl:

Anyway, something jogged my memory this morning that you had 
asked about using the UAH diurnal adjustments in a paper, and 
I didn't respond with a firm answer.  Sorry.  I think it would
be fine to use and critique ... that's sort of what science is
all about.

[John Christy]


13 May 2005  1:58 p.m.

Hi John

Thanks for permission -- I strongly approve of your view of 
science expressed [above].  I think that things that aren't 
nutty or poorly explained should be published in the open 
literature without too much fuss, so that they can then be 
commented on.....  Of course, different people have different 
opinions about what constitutes nutty.

You[r] global diurnal effect agree[s] pretty much with mine, 
but it's the *opposite* sign.  The real difference is in the 
tropics.  I suspect the same calculation for 20S to 20N will 
show a much larger effect.  With the model-based diurnal 
correction, the big disagreement with the surface in the tropics 
goes away.

[Carl Mears  Remote Sensing System] 

So, the apparent contradiction between my testimony and the 
letter from Mr. Wentz sprang from a misunderstanding of how 
two different datasets were being addressed.  One (MT) was 
solved without sharing the specific code but for which we did 
supply ancillary data files and considerable information.  The 
other (LT) needed parts of the code to resolve the discrepancy. 
In the Hearing, Mr. Waxman dealt with the former while I dealt
with the latter.  In both cases, however, UAH did cooperate 
with RSS.

Mears, C.A., M.C. Schabel, and F.J. Wentz, 2003:  A reanalysis 
of the MSU channel 2 tropospheric temperature record. 
J. Climate, 16, 3650-3664.

Mears, C.A. and F.J. Wentz, 2005:  The effect of diurnal 
correction on satellite-derived lower tropospheric temperature. 
Science, 309, 1538-1551.
(2) As you were a member of the National Research Council
panel that recently issued the report on millennial temperature
reconstructions:

(a) Where in the report did the panel describe "plausible" as 
suggesting roughly a 2/3rds probability of being correct.
(b) In the report, did the panel attach probability estimates 
to the term "plausible"?
(c) Why did the panel choose to use the term "plausible," as 
opposed for example to terms such as "likely", to describe 
confidence in millennial temperature reconstructions?

(2a) Answer

The report did not intend for "plausible" to be equated with 
"2/3rds" probability of being correct.  My view ,as a panel 
member, is that "plausible" was chosen to indicate a lack of 
quantifiability in describing confidence in pre-1600 temperatures.

(2b) Answer

"Plausible" was chosen precisely because it implied that 
probability estimates could not be assigned to pre-1600 
temperature estimates due to (a) the limited amount of proxy 
information available and (b) the unknown confidence with which 
these proxy records may determine temperature.  The current proxies
are mostly consistent with the notion that pre-1600 temperatures 
were cooler than late 20th century temperatures, but the evidence 
is still too meager and uncertain.

(2c) Answer

As a member of the IPCC 2001 Lead Author team I outlined in my 
testimony why the word "likely" was chosen in that document.  
"Likely" in the IPCC 2001 terminology had an estimated likelihood 
defined as being at least 2/3rds probable.  The NRC panel chose 
"plausible" for reasons given in (2b) above.  My view of the NRC 
report is that our IPCC statement was inadequate in that the IPCC 
should have separated the last millennium into two periods with 
higher than "likely" confidence for post-1600 and lower than 
"likely" confidence for pre-1600 estimates.  

(3) When considering the panel's findings that it is "plausible" 
that recent decades were the warmest in a millennium, is it 
correct to interpret that to mean the panel's consensus view was 
that plausible means roughly 2/3rds probability of being correct, 
as was suggested in the news reports following the press 
conference releasing the report?

(3) Answer

I was disturbed when reading the press reports that implied the 
panel had endorsed with "likely" confidence statements about the 
pre-1600 temperatures. The panel did not conclude that there was 
a 2/3rds probability that late 20th century warmth was greater 
than at anytime prior to 1600.  As noted above, there are 
indications that such is the case, but the data do not allow
statements of quantifiable confidence to be made at this point.

(4) In your testimony, you mention your recent study relating to 
California regional temperature trends and human influences on 
those trends (Christy et al. 2006a).  Please describe the purpose 
and conclusions of that study.

(4) Answer

As a native of Fresno and an avid weather observer since being a 
teenager there, I had an abiding interest in determining the extent
of temperature changes in the Valley.  This eventually led to a 
study funded by the National Science Foundation.  The first part 
of the study was a data gathering effort in which every available 
long-term dataset for the Valley and nearby Sierras was acquired, 
many by manual digitization from paper records.  The second part 
was the development of a means to merge all of these data into a 
regional time series of temperature for daytime and nighttime 
temperatures separately, for each season separately and for the 
Valley and Sierras separately.  
We discovered that Valley nighttime temperatures were rising 
rapidly while daytime temperatures were generally falling slightly.
In the Sierras however, there were no real significant trends,
with perhaps a suggestion of nighttime cooling in summer and fall. 
This result suggests that the significant changes in the land 
surface of the Valley (irrigation and perhaps urbanization) are 
causing the changes in the Valley.  The fact there were no 
long-term changes in the Sierras for this period suggests that 
the enhanced greenhouse effect has not been a significant factor 
in Central California in terms of temperature changes.  (For 
regions this small, one must always consider the natural variations
of climate as also being an issue with which to deal, but such 
variations should have affected both Valley and Sierra in the 
same way.)

(5) Please explain why the measurement of average global (or 
average hemispheric) temperature change does or does not represent 
an adequate metric for understanding or predicting the risks of
potential climate change impacts.

(5) Answer

Thermometers near the surface will respond to all of the forcing
processes that act upon them.  Thus, surface temperature over 
land will show responses to changes such as urbanization and other
land-use changes in addition to that of atmospheric forcing from
aerosols or greenhouse gases.   As a result, it is difficult to 
extract out the impacts of one particular forcing on surface 
temperature with high confidence.  
Daily temperature is commonly reported as two values, the maximum 
and minimum, from which the daily average is calculated.  Maximum 
temperature is more relevant for climate change as it occurs when
the surface and upper atmosphere are more closely connected 
through vertical mixing and thus will give a better idea of what 
the general climate system as a whole is doing.  Minimum 
temperature is more closely related to a shallow layer near the 
ground and is thus impacted more by urbanization, aerosol pollution
and other land-use changes.  Thus, daily average temperature is 
partially dependent on processes that impact minima. 
Theoretically, the temperature of the ocean surface is a better 
quantity to measure in terms of observing a variable that has a 
more direct relationship to a forcing such as greenhouse gases.  
However, there are large areas of the ocean that have never been 
systematically observed over long-periods, and the manner by which
ocean temperatures have been taken and the associated biases 
contain a certain level of uncertainty, especially in the earliest 
years.
Surface temperature is one metric for assessing climate variations
and change, but is less informative than others.  Indeed the ability 
of model simulations to depict surface temperature distributions is 
quite primitive at this stage.  Focusing on the global average 
surface temperature also circumvents the fact that the spatial 
distribution of those changes is more important than the overall 
average in terms of risk and impact. For example, our work in 
California, the SE USA and preliminary work in East Africa indicate
models are not able to replicate what the observations since 1900
have shown, though for the global average they are not in great 
error.  Additionally, the lowest layer (or boundary layer) of the 
atmosphere in which these surface thermometers are positioned, is
an extremely complicated part of the climate system which is not 
well-represented in climate models. Average surface temperature, 
while valuable in local terms to humans who live on the surface, 
is a rather limited and complicated variable, compounding its 
lack of utility in providing a high level of understanding about
greenhouse-gas induced climate change.
A much more fundamental measurement needed to assess how various 
forcing mechanisms are affecting the planet is the heat content, 
which is essentially the number of joules of energy in the 
system.  So, by counting the number of joules of energy in the 
deep atmosphere, ocean (mainly upper ocean), and other components
such as ice caps, one has access to a better metric for 
understanding how much extra energy is (or is not) being trapped
in the climate system. Knowing the number of joules, however,
is still a step removed from knowing whether particular 
components of the Earth (and human) system might be at "risk"
for a significant impact.
It is a very subjective task to address the idea of "risk" of 
potential impacts of a changing climate (either natural or 
human-induced) from surface temperature considerations, and 
as important, the possible impact of specific policies.  The 
various processes that affect surface temperature render it a 
less-than-optimal gauge of human-induced climate change 
impacts, even if concentrating on the better measure - daily 
maximum temperature.  Thus, it is even more difficult to 
assign an observed change in surface temperature to a 
particular cause.


Questions from Rep. Supak for John R. Christy

(1) In your written testimony, you stated that the poor of 
the world are more vulnerable to the impacts of poverty, 
water and air pollution, and political strife (sic) than to 
whatever the climate does.  You also made a plea that the 
poor of the world not be denied the use of energy.  A recent
article in the Washington Post recorded the tremendous cost 
of subsistence farmers and urban dwellers in Peru because of 
the melting of the glaciers that has caused a water crisis. 
The loss of glacial ice in the Himalayas will affect 300 
million people relying on snowmelt for the water supply.  
(See attached, "On the roof of Peru, Omens in the Ice;  
Retreat of Once-Mighty Glacier signals Water Crisis, Mirroring
Worldwide Trend," July 29, 2006, A1.)

(a) Is it your position that nothing should be done in the 
developed world to control its fossil fuel energy use while
we wait for development to reach these poor people who are 
directly suffering today from the effects of climate change?
(b) What do you propose to protect the poor people of the world 
today from the effects of climate change, particularly as it 
relates to their water supply and ability to raise crops to feed
their families?

This is an important issue to me and I will strive to provide a
policy-relevant answer.  Thank you for addressing an issue that
has considerable import to millions.
The questions above are introduced with a Washington Post news 
article describing the apparent plight of Peruvians who depend
on annual snow/glacial melting for a portion of their water 
needs.  These types of articles generally present dramatic 
assertions and tend to highlight whatever is alarmist and 
attention-grabbing.  After all, the ability of the media to 
survive is dependent on how many people's attention may be 
grabbed.  Assertions are not science.  Science is numbers
(as Lord Kelvin said.)
Tropical glaciers have been advancing and retreating for thousands 
of years, and are not exceptionally good indicators of 
temperature.  (Note for example: Scientists Unravel Mystery of 
Growing Glaciers, 24 Aug 2006, Guardian Unlimited, describing the 
growth of glaciers in the western Himalaya, Karakoram and Hindu 
Kush mountains.)   In Fig. 6.1 of the NRC Surface Temperature 
Reconstruction Report (2006 of which I was a co-author), ice 
cores of three glaciers are shown for South America and three 
for the Tibetan Plateau.  Two of the 6 show an increase in the 
proxy temperature since 1000 A.D. while the other 4 show level or
declining trends.  In particular, the glacier identified in the 
Post article (Quelccaya) shows a long decline (cooling) to about 
1800 with a rise to about 1950 and fairly level since then which
doesn't match human-induced climate change theories well at all.
Dr. Lonnie Thompson, who studies this glacier more than anyone, 
indicated to me that he believed this glacier was about 1,500
years old.  Thus, it appears that these glaciers advance and 
retreat on many time scales and should not be depended upon for 
the long term.  This is what the numbers suggest.
A society which depends on the annual melting of "glacial" ice 
is therefore dependent on an erratic system.  The following 
letter to the editor addresses the problems of the Peruvian water 
situation, noting that ineffective water management rather than
global warming is the problem.

Peru Shows Why Water Privatization Is Needed

Washington Post
Sunday, August 6, 2006; B06

Doug Struck reported on the water crisis in Lima, Peru, and on the
role that accelerated glacier melting has played in recent years 
["On the Roof of Peru, Omens in the Ice," front page, July 29]. 
But more than a billion people throughout the developing world 
lack access to clean water, and that is largely due to the dismal
performance of the public sector, which is in charge of 97 percent
of formal water distribution in poor countries. Water shortages 
are even common in Cherrapunji, India, which has been described 
as the wettest place on Earth.

In Lima, a quarter of the city's 8 million people don't have 
piped water. The article quotes an engineer at Peru's public 
monopoly who suggests that if the utility did connect those 
2 million people, there would not be enough water to serve them.
The article does not mention that some 40 percent of the water 
piped through the public utility is lost to leakages and otherwise 
unaccounted for.

Peru's public water utility has failed to serve a huge percentage
of the population for decades. Privatization would increase 
access to water, reduce death and diseases, and introduce 
accountability and rational pricing, as countless cases of 
successful water privatization around the world have shown. The 
first to benefit would be Lima's poor, who currently pay 
exorbitant black-market prices for water.

IAN V�SQUEZ

Director
Project on Global Economic Liberty
Cato Institute
Washington

The main problem in poor agricultural societies like Peru is that
the country's institutions and regulations encourage wasteful 
water usage in rural areas that particularly harm the poor.
Agricultural productivity is mainly undermined by major factors 
(lack of property rights, closed economies, civil wars, state 
marketing boards, erratic macroeconomic policy, low growth, bad 
infrastructure, etc.) that have nothing whatsoever to do with 
global warming. In areas like Peru where glacier melting seems 
to have reduced water supply, it would be far cheaper to pay for
a range of solutions (a system of dams and irrigation, relocation
of some vulnerable citizens, etc.) than it would to implement 
alternatives that would reduce growth in both rich and poor 
countries and in the end have no impact on the problem.  So the
better approach is to encourage locally-focused solutions at a 
far smaller cost than top-down energy suppression measures which 
in reality will not impact the climate.
In summary, alarmist articles, such as was as attached with these
questions, are not designed to give hard scientific information
from which policy can be made.  The real issues in this arena 
often boil down to how public water management entities have 
failed to store, allocate and distribute water effectively,
efficiently and sustainably.  

(1a) Answer

As indicated in my testimony, it is my view that people should be
given greater access to energy produced by the most efficient
and clean means possible because energy provides longer and better 
lives.  At present, much of the poor's energy is produced from 
biomass burning (wood, dung) which destroys habitat and fouls the 
air with toxic smoke.  In that context, energy from fossil fuels 
can be an environmental and humanitarian step forward.  Though 
expensive and intermittent, other sources, such as solar or wind,
could help fill part of the gap.  However, cost, reliability and
base-load power requirements are three factors that must be 
considered and which tend to work against solar and wind.
I do not subscribe to the notion that climate change (about which 
we can do anything about) is causing these people serious problems
today.  Tropical glaciers are known to have advanced and retreated
many times in the past.  People who are dependent on a particular 
status quo of a dynamical system like mountain glaciers are
operating in a belief-system that the actual climate cannot 
guarantee.  The present retreat of several of the glaciers in this 
part of the tropics leads one to hope these people can adapt to 
such variability.  (But note above the growth of glaciers in South
Asia.)  Their water still falls as rain and snow, and capturing 
that water for dry spells is a prudent plan to pursue.  The issue 
of water policy goes far beyond Peru and the impacts of climate 
change (see below).

(1b) Answer

Let me first say that the future distribution and quantity of 
rainfall is unknown.  Rainfall patterns have been notoriously 
variable over the centuries as evidenced by paleo-climate research
during the period when no human-influence on climate was possible. 
Additionally, rainfall in general is more important than temperature 
for sustaining life.  
Climate models are unable to confidently predict where the rain may 
increase, decrease or stay the same.  Further, efforts to "control"
climate change are misguided as we have no way to confidently 
determine how a particular policy for controlling greenhouse gases 
will impact precipitation.
Water policy is a vast and complex issue with climate variability 
being only one component.  The political aspects of water 
availability are significant and the growth of water-dependent 
systems (human and agricultural) in desert areas is going to be 
a challenge to sustain whatever the climate does (see introductory
comments to these answers).  In the U.S. for example, we know that 
creating the availability and performance of an acre-foot of fresh 
water in California (where over 80% goes to irrigation) costs about
15 times that of creating the same acre-foot in Alabama.  Where 
then should the country invest its funds for the most benefit, both
financially and environmentally?
The policy-relevant issues for a political body are to determine 
(1) where and how much water there is, (2) who owns the water and 
therefore who controls its use, (3) what uses are sustainable
environmentally, financially and politically, (4) what 
infrastructure may be built to use the available water efficiently, 
confidently and sustainably, and (5) what incentives are available
to pay for (4).  
I suspect water will become more and more commoditized in the 
future, so that some investment will come from the commercial 
sector to store and distribute water.  How governments, especially
poor governments, take advantage of such investments to provide 
clean water for human consumption (and a great leap forward in
health care) will be done on a country-by-country basis, but I 
cannot predict how effective that process will be.  U.S. policymakers 
could facilitate the reduction of water crises by helping governments
answer these 5 questions.

(2) Your published work on satellite-derived lower tropospheric 
temperature data was used for several years as evidence that there 
is no global warming, since it appeared to show that the 
temperatures in the tropics were actually cooling.  In 2005, 
Dr. Carl Mears and Dr. Frank Wentz of Remote Sensing Systems in 
Santa Rosa, California, published an article in Science magazine 
showing that, because of orbital drift and decay that was not 
controlled for in your study, the temperature measurements were 
gradually taken later and later in the day when temperatures 
were cooling.  The article also found a mathematical error in 
your work.  When corrected, the data pointed to an increase in 
tropical temperatures, not a decrease.

Is you original work still being used as evidence that there is
no global warming?  Have you corrected this work?

There are a number of issues intermingled in these comments and
questions that need clarification.  Beginning in June 1998 and 
for every month since then, the University of Alabama in 
Huntsville (UAH) global temperature measurements reported positive 
global trends for all versions of the lower tropospheric (LT)
temperature dataset.  The tropical trends were not different from
a zero trend when Mears and Wentz began looking at the methodology
of our version 5.1 (v5.1).  As noted in my testimony they 
discovered an artifact of our adjustments for satellite drift which 
created a cooling error in the tropics for LT.  (We produce other 
temperature products which used the same methodology to account 
for this drift but which were not affected by this artifact.)
A fair bit of confusion arose when Mears and Wentz published the 
discovery of this error in August 2005 and in the same 
publication introduced a new LT dataset of their own.  The
implication of this publication was that the error they found
was the difference between our old dataset and their new dataset
which was significant, about 0.10 �C/decade. In other words, the
impression given in the article was that their new dataset 
represented a corrected version of our old dataset.  Unfortunately,
this was not the case.  The actual impact of the error in UAH's 
v5.1 was not addressed in their paper.  As Roy Spencer and I 
published in Science magazine later in 2005, the effect of that 
error was small, +0.035 �C/decade (at that time from +0.090 to 
+0.125 �C/decade), being within our originally published error 
margin assigned to v5.1.  In the tropics, the effect was to
increase the trend from  +0.00 to +0.05 �C/decade.
We corrected the error in May 2005 and with the publication of 
Mears and Wentz put the data on a public website in August 2005, 
though it was provided to several scientists before that date.  
This new version, v5.2, has been publicly available since that 
time.  So there are two LT datasets with somewhat differing trends,
UAH's and RSS's.
Of interest to the committee is the fact I will have two papers to 
be published shortly which indicate UAH v5.2 is highly consistent
with independent temperature measurements of the LT layer.  These
papers show that it is very likely that the tropical atmosphere 
is warming at a rate equal to or less than that of the surface, a 
characteristic no climate model that we have examined replicates. 
Thus, there is evidence that the theoretical ideas of how the 
large-scale atmosphere should be responding to the enhanced 
greenhouse effect, as embodied in climate models, still have 
shortcomings.
As to the first question, we provide only the latest version of
our data to the public.  And, since 1998 any version of our lower
tropospheric dataset would have shown a positive global trend. 
Thus, if someone is using UAH data to claim no global warming, I 
would speculate they are likely using pre-1998 data or are somehow 
altering the data to make that conclusion.  I don't know of any
current claims to that effect, and UAH has been forthright in
reporting positive trends (and the likelihood that at least part
of that positive trend is due to enhanced greenhouse gases) these 
past 8 years.
In answering the second question, the discussion above describes 
the events that led to the correction of the drift error and UAH's
corrected data have been publicly available since August 2005. 
However, one should be aware that datasets are always subject to 
revision, and we look forward to v6.0 of our current dataset, though
there will be little change in the outcome relative to v5.2.