[House Hearing, 110 Congress]
[From the U.S. Government Publishing Office]
DISAPPEARING POLAR BEARS AND
PERMAFROST: IS A GLOBAL WARMING
TIPPING POINT EMBEDDED IN THE ICE?
=======================================================================
HEARING
BEFORE THE
SUBCOMMITTEE ON INVESTIGATIONS AND
OVERSIGHT
COMMITTEE ON SCIENCE AND TECHNOLOGY
HOUSE OF REPRESENTATIVES
ONE HUNDRED TENTH CONGRESS
FIRST SESSION
__________
OCTOBER 17, 2007
__________
Serial No. 110-64
__________
Printed for the use of the Committee on Science and Technology
Available via the World Wide Web: http://www.house.gov/science
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______
COMMITTEE ON SCIENCE AND TECHNOLOGY
HON. BART GORDON, Tennessee, Chairman
JERRY F. COSTELLO, Illinois RALPH M. HALL, Texas
EDDIE BERNICE JOHNSON, Texas F. JAMES SENSENBRENNER JR.,
LYNN C. WOOLSEY, California Wisconsin
MARK UDALL, Colorado LAMAR S. SMITH, Texas
DAVID WU, Oregon DANA ROHRABACHER, California
BRIAN BAIRD, Washington ROSCOE G. BARTLETT, Maryland
BRAD MILLER, North Carolina VERNON J. EHLERS, Michigan
DANIEL LIPINSKI, Illinois FRANK D. LUCAS, Oklahoma
NICK LAMPSON, Texas JUDY BIGGERT, Illinois
GABRIELLE GIFFORDS, Arizona W. TODD AKIN, Missouri
JERRY MCNERNEY, California JO BONNER, Alabama
LAURA RICHARDSON, California TOM FEENEY, Florida
PAUL KANJORSKI, Pennsylvania RANDY NEUGEBAUER, Texas
DARLENE HOOLEY, Oregon BOB INGLIS, South Carolina
STEVEN R. ROTHMAN, New Jersey DAVID G. REICHERT, Washington
JIM MATHESON, Utah MICHAEL T. MCCAUL, Texas
MIKE ROSS, Arkansas MARIO DIAZ-BALART, Florida
BEN CHANDLER, Kentucky PHIL GINGREY, Georgia
RUSS CARNAHAN, Missouri BRIAN P. BILBRAY, California
CHARLIE MELANCON, Louisiana ADRIAN SMITH, Nebraska
BARON P. HILL, Indiana PAUL C. BROUN, Georgia
HARRY E. MITCHELL, Arizona
CHARLES A. WILSON, Ohio
------
Subcommittee on Investigations and Oversight
HON. BRAD MILLER, North Carolina, Chairman
JERRY F. COSTELLO, Illinois F. JAMES SENSENBRENNER JR.,
EDDIE BERNICE JOHNSON, Texas Wisconsin
DARLENE HOOLEY, Oregon DANA ROHRABACHER, California
STEVEN R. ROTHMAN, New Jersey DAVID G. REICHERT, Washington
BRIAN BAIRD, Washington PAUL C. BROUN, Georgia
BART GORDON, Tennessee RALPH M. HALL, Texas
DAN PEARSON Subcommittee Staff Director
EDITH HOLLEMAN Subcommittee Counsel
JAMES PAUL Democratic Professional Staff Member
DOUG PASTERNAK Democratic Professional Staff Member
KEN JACOBSON Democratic Professional Staff Member
TOM HAMMOND Republican Professional Staff Member
STACEY STEEP Research Assistant
C O N T E N T S
October 17, 2007
Page
Witness List..................................................... 2
Hearing Charter.................................................. 3
Opening Statements
Statement by Representative Brad Miller, Chairman, Subcommittee
on Investigations and Oversight, Committee on Science and
Technology, U.S. House of Representatives...................... 7
Written Statement............................................ 9
Statement by Representative F. James Sensenbrenner, Ranking
Minority Member, Subcommittee on Investigations and Oversight,
Committee on Science and Technology, U.S. House of
Representatives................................................ 10
Written Statement............................................ 11
Prepared Statement by Representative Jerry F. Costello, Member,
Subcommittee on Investigations and Oversight, Committee on
Science and Technology, U.S. House of Representatives.......... 12
Witnesses:
Dr. Richard B. Alley, Evan Pugh Professor of Geosciences,
Department of Geosciences, Pennsylvania State University
Oral Statement............................................... 13
Written Statement............................................ 15
Biography.................................................... 18
Dr. Glenn Patrick Juday, Professor of Forest Ecology, School of
Natural Resources and Agricultural Sciences, University of
Alaska at Fairbanks
Oral Statement............................................... 19
Written Statement............................................ 34
Biography.................................................... 37
Dr. Susan D. Haseltine, Associate Director for Biology, U.S.
Geological Survey, U.S. Department of Interior
Oral Statement............................................... 37
Written Statement............................................ 39
Biography.................................................... 42
Ms. Kassie R. Siegel, Director, Climate, Air and Energy Program,
Center for Biological Diversity, Joshua Tree, California
Oral Statement............................................... 43
Written Statement............................................ 47
Biography.................................................... 76
Discussion
Relation of Astrophysics to the Arctic and Polar Bears......... 77
Ms. Siegel's Background........................................ 79
Are Humans Causing Climate Change?............................. 79
Climate Change From the Earth's Orbit.......................... 80
Evidence of Climate Change..................................... 81
Dr. Hansen and George Soros.................................... 82
Scientists Named Steve......................................... 86
Processes Leading to the Tipping Point......................... 87
Polar Bear Population Changes in Canada........................ 88
Naturally Occurring Climate Change............................. 89
Reducing Methane Emissions..................................... 93
Action Items to Reduce Emissions............................... 94
Polar Bear Populations 1,000 Years Ago......................... 95
Climate Change Since the Last Ice Age.......................... 96
Climate Change From Carbon Methane in the Permafrost........... 97
DISAPPEARING POLAR BEARS AND PERMAFROST: IS A GLOBAL WARMING TIPPING
POINT EMBEDDED IN THE ICE?
----------
WEDNESDAY, OCTOBER 17, 2007
House of Representatives,
Subcommittee on Investigations and Oversight,
Committee on Science and Technology,
Washington, DC.
The Subcommittee met, pursuant to call, at 10:05 a.m., in
Room 2318 of the Rayburn House Office Building, Hon. Brad
Miller [Chairman of the Subcommittee] presiding.
hearing charter
SUBCOMMITTEE ON INVESTIGATIONS AND OVERSIGHT
COMMITTEE ON SCIENCE AND TECHNOLOGY
U.S. HOUSE OF REPRESENTATIVES
Disappearing Polar Bears and
Permafrost: Is a Global Warming
Tipping Point Embedded in the Ice?
wednesday, october 17, 2007
10:00 a.m.-12:00 p.m.
2318 rayburn house office building
Purpose:
On Wednesday, October 17, 2007, the Investigations and Oversight
Subcommittee will hold a hearing on the impacts of global warming on
the Arctic. This hearing will provide the Committee with an opportunity
to hear from witnesses on three interrelated matters: (1) the current
situation in the Arctic, including the situation facing the polar bear,
(2) ways in which warming in the Arctic may accelerate global warming,
especially through the emission of more greenhouse gases, and (3)
interim steps that could be taken to reduce greenhouse gas emissions
while the Congress weighs more elaborate carbon trade or tax proposals.
One of the themes that should emerge from this hearing is that,
from a layman's perspective, the models used to project climate change
and its ramifications appear to be conservative in their projections.
This is because any phenomena that are not understood well enough to be
represented in models with confidence are excluded. These other
phenomena may accentuate or depress warming trends. In the case of the
Arctic, most of the phenomena that have been excluded from the models
are believed to accentuate warming and its effects. Few will depress
it. The modeling on polar bear survival, for example, uses projections
from the IPCC models to estimate future changes in sea ice extent.
Since the bears' condition is very dependent upon both the extent of
the sea ice and the duration of ice-free periods, projections of the
bear survival are very dependent upon projections of sea ice. This
summer the sea ice extent is far less than projected by the models.
Some important factors that induce additional warming are either
left out of IPCC models or are not fully accounted for, and therefore
the actual decrease in sea ice extent could be significantly greater
than the IPCC projections. For example, the IPCC modeling fails to
include positive feedbacks from permafrost thawing which could add
millions--even billions--of metric tons of greenhouse gases to the
environment. Projections of sea level rise in the IPCC exercise do not
include any run-off from melting ice sheets in Greenland or Antarctica
because the physical dynamics of that process are so poorly understood.
The result is that, as disturbing as the polar bear study is or as
worrisome as the IPCC reports are, they probably minimize the global
warming path we are on and the consequences we will live through as a
result of that warming.
Recent Global Warming Reports Related to the Arctic
The past twelve months have seen two remarkable stories related to
the Arctic. In January of 2007, the Department of the Interior proposed
to list the Polar Bear as an endangered species. This proposal came in
response to a successful lawsuit brought by the Center for Biological
Diversity, which charged that the decline in the bear's habitat--a
direct consequence of global warming--justified a listing. Subsequent
information developed by the U.S. Geological Survey (USGS) provides
ample reason to believe that the bear will disappear entirely from
large areas of its range in the next fifty years, and will be on the
verge of extinction by 2100.
Diminishing ice cover is directly tied to the survival of the polar
bear. Bears rely on ice from which to hunt seals--their main prey. The
analysis done by the USGS projects that in three of the four ice eco-
regions of the Arctic, it is most likely that the bears will be
eliminated by 2100. In the fourth region, the modeling projects almost
even odds that the bears will be somewhere between retaining a small
population to being extinct, but it appears that even a small
population may not be enough for sustaining the species beyond 2100.
The disturbing quality of the USGS analysis is that their models
were derived from statistical projections that have not predicted as
steep a decline of actual ice loss as has occurred in the Arctic. In
other words, the modeling of polar bear populations assumes more ice
extent than the real world is actually producing. Further, there was no
accommodation to the modeling made for the consequences of other
environmental factors that may occur if the world begins to extract
more resources from the Arctic and if a Northwest Passage becomes a
reliable shipping route. Such activities would have a further negative
effect on a remaining polar bear population.
The second event that has received widespread attention has been
the report that the melt of Arctic sea ice set a record for a new
summer minimum. The National Snow and Ice Data Center (NSIDC) announced
on October 1 that the ``Arctic sea ice during the 2007 melt season
plummeted to the lowest levels since satellite measurements began in
1979.'' The NSIDC lead scientist, Mark Serreze, commented that ``The
sea ice cover is in a downward spiral and may have passed the point of
no return. As the years go by, we are losing more and more ice in
summer and growing back less and less ice in winter. We may well see an
ice-free Arctic Ocean in our lifetimes. The implications for global
climate, as well as Arctic animals and people, are disturbing.'' There
has not been an ice-free summer in the Arctic in one million years.
Diminishing bears and sea ice are only the most widely reported
aspects of a warming Arctic. Global climate scientists worry about
``tipping points''--environmental processes that could lead to rapid
and irreversible changes in the overall global climate or in sea level
rise. The Arctic contains several potential sources of a tipping point
in the boreal forests, the albedo effects of melting ice and, one of
the most worrisome, permafrost.
Tipping Points in the North
The Arctic permafrost acts as a kind of frozen locker in which
carbon is stored. These frozen soils, as well as frozen peat, extend
over large areas of North America and Siberia--perhaps as much as 80
percent of the area. Much of the infrastructure of Russia, Alaska, and
the Canadian North is built on permafrost. With thawing of permafrost,
some of which extends more than 100 feet in depth, subsidence occurs;
peoples' homes, roads, and pipes all could be damaged or destroyed. As
disturbing as these consequences are, from a global perspective there
is a more profound result: thawing permafrost release stored carbon as
either carbon dioxide or as methane.
Estimates of the total stored carbon in Arctic soils are in the
range of one thousand gigatons. (See Zimov, Schuur, Chapin III,
``Permafrost and the Global Carbon Budget,'' Science Magazine, Vol.
312, 16 June, 2006). No one knows how much is currently being released,
though there are anecdotal reports of methane emerging so quickly from
pools in Siberia that it keeps ice from freezing in the dead of winter.
The Stordalen mire in Sweden has been observed to produce a 22-66
percent increase in methane emission as the permafrost thawed.
(Christensen, et. al., ``Thawing sub-arctic permafrost: Effects on
vegetation and methane emissions,'' Geophysical Research Letters, V.
31, L04501, 2004).
Work done at the National Center for Atmospheric Research (NCAR)
projects that over half of the topmost layer of permafrost (top ten
feet) will have thawed by 2050 and as much as ninety percent could thaw
by 2100. The analysts worked on this question with an eye to modeling
increased water runoff from the permafrost into the Arctic Ocean. Their
model did not tackle the question of carbon emissions from thawing
permafrost, but they conceded that such releases ``may be considerable
and the feedback is likely to be positive and possibly large.''
(Lawrence & Slater, ``A Projection of Severe Near-Surface Permafrost
Degradation During the 21st Century,'' Geophysical Research Letters, V.
32, L24401, 2005).
While scientists know that thawing permafrost and the release of
carbon stored in its frozen matrix could have an enormous impact on
overall greenhouse gas emissions, none of the modeling done for the
IPCC takes this feedback mechanism into consideration. Past and present
anthropogenic emissions of greenhouse gases may so warm the planet that
aggressive efforts over the next thirty years to reduce anthropogenic
emissions may not be enough to stop the thawing of permafrost and the
release of the enormous stores of carbon in those soils.
Permafrost is not the only potential source of accelerated warming.
Another potential source for carbon releases lies in the boreal forests
of the North. The region is warming and large areas of North America's
Arctic have been subjected to drought. The warmer weather has made the
region more hospitable to insects that have attacked the massive
conifer boreal forests. In the Province of British Columbia, Canada,
pine beetles have become an ``epidemic.'' As of 2006, the beetles had
destroyed $6 billion worth of trees and the provincial government began
pushing a massive logging increase to try to get ahead of the insect-
driven losses. It is estimated that B.C. alone contains almost seven
percent of the world's softwood. As a researcher at the Pacific
Forestry Centre in Victoria, Allan Carroll, puts it, ``There's no
question [the pine beetles] range has expanded over the last 30 years
due to ameliorating climate. . .'' (Webster & Cathro, ``Bitter Harvest:
Pine Beetle Infestation in B.C.,'' Canadian Business, January 2006).
Insect-weakened, dry trees are subject to fire. This past summer
saw the largest forest fire ever witnessed on Alaska's North slope. On
July 16, 2007 lightning started a fire that was still burning in the
first week of October. It had consumed more than a quarter of a million
acres of forest during its run, and the smoke plume could be seen from
50 miles away. Scientists in Alaska are concerned that the fire may
have damaged the permafrost beneath the forest, causing deeper thaw. As
these trees burn, and others succumb to drought and insects, carbon is
released into the atmosphere. The loss of trees to store carbon and the
release of carbon from dying forests is a potentially important source
of greenhouse gases. (Hopkin, ``Alaskan Fire Damages Permafrost,''
Nature, published online 9 October 2007).
Finally, the change in albedo in the North could have an important
impact on overall global temperature. As snow and ice melt, they reveal
the darker Earth and ocean. The overall color of the planet's surface
directly affects how much solar energy is absorbed by the planet and
how much is reflected back out into space. Being darker, the sea will
absorb more solar energy, warming the seas and accelerating the melting
of the ice. A similar process happens on land that would traditionally
be covered by snow. (Note that the loss of boreal forests may have a
small negative feedback by revealing a lighter ground under the dark
trees--thus reflecting marginally more solar energy back into space
than the forests).
Any of these processes that either cause the Earth to absorb or
retain more solar radiation will add to the overall warming of our
atmosphere. If the atmosphere warms enough to reach a tipping point on
the ice sheets of Greenland or Antarctica, the consequences for coastal
communities and the world economy would be devastating. Scientists do
not fully understand the dynamics of ice sheet melting, but it is not a
simple linear process where a certain temperature produces a certain
rate of melt. Rather there are feedbacks in the melting of the sheets
that suggests an exponential or accelerating reaction occurs when
melting begins. If the ice sheets of Greenland and Antarctica were to
both melt, it would increase the sea level by approximately 200 feet.
Experts believe that such an event is extremely unlikely. As one of our
witnesses will testify, it is expected that increases in sea level will
not occur so rapidly as to raise sea level at the rate of meters over
coming decades. However, because the physical dynamics of ice sheet
melting are not well understood, they were simply left out of the
IPCC's most recent projections of sea level rise in the 21st Century.
We currently have no reliable, comprehensive projection of sea level
rise due to this gap in our understanding of ice sheet dynamics in
conditions of warming.
A Modest Proposal for Action
The Center for Biological Diversity will appear to provide some
advice on steps that can be taken to reduce warming, with particular
emphasis on their efficacy in the Arctic. Among the steps they advocate
are programs to reduce methane emissions and ``black carbon.'' Black
carbon is soot that, in the Arctic, has a particularly pernicious
effect. When it is deposited on snow and ice it decreases its
reflectivity and increases its heat absorption leading to greater
melting. As the Arctic comes under more and more industrialization with
other warming, one could anticipate further production of black carbon.
Methane is a powerful greenhouse gas, with an estimated global warming
potential 23 times greater than carbon dioxide over a 100-year time
frame. Methane is a precursor to tropospheric ozone. In that form, it
traps shortwave radiation as it enters the Earth's atmosphere from the
sun and then when it is reflected back again by snow and ice. As a
consequence, its impact is strongest over the Poles. Reducing global
methane emissions would provide a particular benefit to the Arctic.
Witnesses
Dr. Sue Haseltine is the Associate Director for Biology at the U.S.
Geological Survey, U.S. Department of Interior and will make a
presentation of their findings regarding the future of the polar bear.
Ms. Kassie R. Siegel is the Director of the Climate, Air and Energy
Program at the Center for Biological Diversity. She will present their
preliminary plan for the mitigation of methane emissions.
Dr. Richard Alley, Evan Pugh Professor of Geosciences at Pennsylvania
State University, appeared before the Committee to testify about the
findings of the IPCC report earlier this year. He will testify about
matters including sea ice, albedo and ice sheet melting. He can also
answer questions regarding what factors have and have not been included
in IPCC modeling on the climate.
Dr. Glenn Juday is a Professor at the School of Natural Resources and
Agricultural Sciences, University of Alaska at Fairbanks, one of the
worlds leading centers for the study of the Arctic. He will testify
regarding both permafrost--what we do and do not understand about its
potential release of carbon--and the boreal forests.
Chairman Miller. Good morning. The hearing will come to
order. Today's hearing is entitled Disappearing Polar Bears and
Permafrost: Is a Global Warming Tipping Point Embedded in the
Ice?
This committee held three hearings on the 2007 report of
the Intergovernmental Panel on Climate Change, IPCC, one of
last week's winners of the Nobel Prize for Peace. The report of
the working group on impact, adaptation, and vulnerability
stated that the rapid climate changes occurring in the Earth's
polar regions would have cascading effects on key regional bio-
physical systems and cause global climatic feedbacks.
The report described the polar regions as geopolitically
and economically important and extremely vulnerable to current
and projected climate change. And the report said the polar
regions had the greatest potential to affect global climate
change and thus human populations and biodiversity.
In the past twelve months, there have been two remarkable
stories related to the Arctic that suggest that those climate
changes may be happening even faster than predicted and with
significant negative consequences. Earlier this month, the
National Snow and Ice Data Center at the University of Colorado
reported that the Arctic sea ice cover in the summer of 2007
had fallen to its lowest point since 1979. Sea ice coverage was
39 percent below the long-term average for 1979 to 2000 and
perhaps half the sea ice coverage of the 1950s.
According to the Center, Arctic sea ice has long been
recognized as a sensitive climate indicator. When global
temperatures rise, the sea ice cover sinks, and global
temperatures in the Arctic have risen four degrees Fahrenheit
since 1950. The lead scientist for the Snow and Ice Center
warned that the sea ice cover is in a downward spiral and may
have passed the point of no return. As the summers go by, we
are losing more and more ice in the summer and growing less and
less back in the winter. We may well see an ice-free Arctic
Ocean in our lifetimes. The implications for global climate, as
well as Arctic animals and people, are disturbing.
There has not been an ice-free summer in the Arctic in a
million years.
Not surprisingly, the U.S. Geological Survey in September
issued a report projecting that, based on the projected sea ice
melts, two-thirds of the world's polar bears will be gone by
2050. The USGS study projects that in three of the four ice
eco-regions of the Arctic, it is most likely that the bears
will be extinct by 2010. In the fourth region, the modeling
projects almost even odds that the bears will be somewhere
between having a small population to being extinct, but a small
population may not be enough to sustain the species.
Polar bears are adapted to hunting from sea ice. They hunt
primarily ringed seals and to a lesser degree bearded seals.
Less sea ice means less habitat. The USGS analysis relied on
models to project polar bear populations that are more
conservative about the melting of sea ice than the steeper
decline that is now being observed in the Arctic. Polar bears
are adapted to hunting from sea ice.
Diminishing bears and sea ice are only the most widely
reported aspects of a warming Arctic. Global climate scientists
worry about tipping points, atmospheric processes that could
lead to a rapid and irreversible change in the overall global
climate or in sea level rise. The Arctic contains several
potential sources of a tipping point in the boreal forests, the
albedo effect of melting ice and one of the most frightening,
carbon and methane release from melting permafrost.
Again, the polar regions, the Arctic and the Antarctic,
have the greatest potential of any region to affect global
climate everywhere. The impacts of global warming will be
greater in the polar regions, and those impacts will also
produce feedback effects that have globally significant
consequences. First, ice and snow reflect solar radiation in a
process known as albedo. It helps keep the Arctic cool and the
Earth cooler. When there is less ice and less snow, the exposed
soil and water absorb solar radiation instead of reflecting it;
and more solar radiation and warmth reaches land and stays in
the atmosphere. It becomes a cycle. Ice melts and snow cover is
reduced, resulting in less reflectivity and more warming,
resulting in more ice melting and reduction of snow cover and
on and on.
Second, because of higher temperatures in the Arctic, the
permafrost beneath large sections of Europe, Russia, Alaska and
Canada is also beginning to melt. There are estimated to be
almost 1,000 gigatons of carbon trapped in Arctic permafrost. A
gigaton is a billion tons. Human use of fossil fuels currently
emits approximately seven gigatons of carbon annually. In 2005,
scientists at the Snow and Ice project projected 50 percent
decrease of the topmost layer of permafrost by 2050 and as much
as a 90 percent decrease by 2100. If that happens, the
resulting release of CO2, carbon dioxide, and
methane could have a warming effect on our climate that defies
imagination.
Another potential source for carbon release rests in the
boreal forests of the North. Warmer weather has made them
vulnerable to insect pests, and drought has resulted in the
largest forest fire ever witnessed on Alaska's Northern Slope.
It may also have damaged the permafrost.
None of the models used in the IPCC projections of the
impact of global warming took into account the potential
release of those gigatons of carbon. A vast area of the world
that has been a net carbon sink could become a carbon dioxide
and methane producer that would dwarf the production of carbon
dioxide and methane now resulting from human activities. As Dr.
Ted Schuur wrote in Science magazine, factors inducing high-
latitude climate warming should be mitigated to minimize the
risk of a potentially large carbon release that would further
increase global warming.
Rapid Arctic ice and permafrost melt are the kind of events
with cascading effects that tip the planet's climate into an
uncontrollable cycle of warming. The result could be an
acceleration of the melting of the ice sheets in Greenland,
inundating coastal communities and devastating the world
economy.
For 20 years we have heard warnings from scientists, first
in a hearing here held by Mr. Gore, an alumnus of this
committee.
Now we are seeing the consequences of global warming in the
endangering of polar bears, in the eroding infrastructure of
the Arctic and in melting sea ice.
Dr. James Hansen of NASA said a year ago that we have 10
years to act. If he is right, we have nine years left to put
this country and the world on a path to reducing aggressively
our carbon emissions. We certainly can do that and probably at
a relatively modest cost if we have the will.
Some dismiss the threat of global warming as gloom and
doom, and proclaim themselves to be sunny optimists who believe
things will turn out all right. Willfully ignoring dangers and
turning a blind eye to all evidence that there is a problem
that needs our urgent attention is not optimism, it is folly.
It is optimism to believe that we will prove equal to the
challenges before us, however daunting; and I am optimistic in
that respect, but we better get about it.
[The prepared statement of Chairman Miller follows:]
Prepared Statement of Chairman Brad Miller
This committee held three hearings on the 2007 report of the
Intergovernmental Panel on Climate Change (IPCC), one of last week's
winners of the Nobel Prize for Peace. The report of the working group
on impact, adaptation and vulnerability stated that the rapid climate
changes occurring in the Earth's polar regions would have ``cascading
effects on key regional bio-physical systems and cause global climatic
feedbacks.'' (``Climate Change 2007: Impacts, Adaptation and
Vulnerability,'' Chapter 15, p. 655, Fourth Assessment Report of the
IPCC.) The report described the polar regions as geopolitically and
economically important and extremely vulnerable to current and
projected climate change. And the report said the polar regions had the
greatest potential to affect global climate change and thus human
populations and biodiversity. Id.
In the past twelve months, there have been two remarkable stories
related to the Arctic that suggest that those climate changes may be
happening even faster than predicted and with significant negative
consequences. Earlier this month, the National Snow and Ice Data Center
at the University of Colorado reported that the Arctic sea ice cover in
the summer of 2007 had fallen to its lowest point since 1979. Sea ice
coverage was 39 percent below the long-term average from 1979 to 2000,
and perhaps half the sea ice coverage of the 1950s.
According to the Center, Arctic sea ice has long been recognized as
a sensitive climate indicator. When global temperatures rise, the sea
ice cover shrinks. And global temperatures in the Arctic have risen
four degrees Fahrenheit since 1950. The lead scientist for the Snow and
Ice Center warned that, ``The sea ice cover is in a downward spiral and
may have passed the point of no return. As the years go by, we are
losing more and more ice in summer and growing back less and less ice
in winter. We may well see an ice-free Arctic Ocean in our lifetimes.
The implications for global climate, as well as Arctic animals and
people, are disturbing.''
There has not been an ice-free summer in the Arctic in a million years.
Not surprisingly, the U.S. Geological Survey in September issued a
report projecting that, based on projected sea ice melts, two-thirds of
the world's polar bears will be gone by 2050. The USGS projects that in
three of the four ice eco-regions of the Arctic, it is most likely that
the bears will be extinct by 2100. In the fourth region, the modeling
projects almost even odds that the bears will be somewhere between
having a small population to being extinct, but a small population may
not be enough to sustain the species.
Polar bears are adapted to hunting from sea ice. They hunt
primarily ringed seals and, to a lesser degree, bearded seals. Less sea
ice means less habitat. The USGS analysis relied on models to project
polar bear populations that are more conservative about the melting of
sea ice than the steeper decline being observed in the Arctic. Further,
the modeling did not consider the consequences of permafrost melt and
other environmental influences that would apply if the world begins to
extract more resources from the Arctic, and if a Northwest Passage
becomes a reliable shipping route. Those activities would have an
obvious negative effect on any remaining polar bear population.
Diminishing bears and sea ice are only the most widely reported
aspects of a warming Arctic. Global climate scientists worry about
``tipping points''--atmospheric processes that could lead to rapid and
irreversible changes in the overall global climate or in sea level
rise. The Arctic contains several potential sources of a tipping point
in the boreal forests, the albedo effects of melting ice and--one of
the most frightening--carbon and methane release from melting
permafrost.
Again, the polar regions--the Arctic and the Antarctic--have the
greatest potential of any region to affect global climate everywhere.
The impacts of global warming will be greater in the polar region, and
those impacts will also produce feedback effects that have globally
significant consequences. First, ice and snow reflect solar radiation
in a process known as ``albedo.'' It helps keep the Arctic cold and the
Earth cooler. When there is less ice and less snow, exposed soil and
water absorb solar radiation instead of reflecting it, and more solar
radiation and warmth reaches land and stays in the atmosphere. It's a
cycle: Ice melts and snow cover is reduced, resulting in less
reflectivity and more warming, resulting in more ice melting and
reduction of snow cover.
Second, because of higher temperatures in the Arctic, the
permafrost beneath large sections of Europe, Russia, Alaska and Canada
is also beginning to melt. There are estimated to be almost 1,000
gigatons of carbon trapped in the Arctic permafrost. A gigaton is a
billion tons. Human use of fossil fuels currently emits approximately
seven gigatons of carbon annually. In 2005, scientists at the Snow and
Ice Data Center projected 50 percent of the topmost layer of permafrost
would melt by 2050 and as much as 90 percent by 2100. If that happens,
the resulting releases of CO2 and methane could have a
warming effect on our climate that defies imagination. Another
potential source for carbon release rests in the boreal forests of the
North. Warmer weather has made them vulnerable to insect pests, and
drought has resulted in the largest forest fire ever witnessed on
Alaska's Northern Slope. It may also have damaged the permafrost.
None of the models used in the IPCC projections of the impact of
global warming took into account the potential release of these
gigatons of carbon. A vast area of the world that has been a net carbon
sink could become a carbon dioxide and methane producer that would
dwarf the production of carbon dioxide and methane now resulting from
human activities. As Dr. Ted Schuur wrote in Science magazine in June
of 2006, ``Factors inducing high-latitude climate warming should be
mitigated to minimize the risk of a potentially large carbon release
that would further increase global warming.''
Rapid Arctic ice and permafrost melt are the kind of events with
``cascading effects'' that tip the planet's climate into an
uncontrollable cycle of warming. The result could be an acceleration of
the melting of the ice sheets in Greenland, inundating coastal
communities and the devastating the world economy.
For twenty years we have heard warnings from scientists--first in a
forum here held by Mr. Gore, an alumnus of this committee.
Now we are seeing the consequences of global warming in the
endangering of polar bears, in the eroding infrastructure of the Arctic
and in the melting sea ice.
Dr. James Hansen of NASA said a year ago that we have ten years to
act. If he is right, we have nine years left to put this country, and
the world, on a path to reducing aggressively our carbon emissions. We
certainly can do it, and probably at a relatively modest cost, if we
have the will.
Some dismiss the threat of global warming as gloom and doom, and
proclaim themselves to be sunny optimists who believe things will turn
out all right. Willfully ignoring dangers and turning a blind eye to
all evidence that there are problems that need our urgent attention is
not optimism, it is folly. It is optimism to believe that we can prove
equal to the challenges before us, however daunting. But we better get
about it.
Chairman Miller. The Chair now recognizes Mr.
Sensenbrenner, for an opening statement.
Mr. Sensenbrenner. Thank you very much, Mr. Chairman.
Today's hearing takes a wide breadth, from predicted declines
in polar bear populations, to whether polar bears should be
listed under the Endangered Species Act, to melting permafrost
and its implications to the ecological affect of climate change
on spruce tree populations. Individual topics are too complex
to approach in depth in a single hearing, but the common thread
is obviously climate change and the underlying truth that the
Arctic is melting.
There is obvious value in bringing the world's attention to
the problem, but we may have reached a tipping point when it
comes to raising awareness on climate change. We have the
world's attention; the question now is what we're going to do
about it. As the diverse subject matter of today's hearing
suggests, climate change can have broad effects that we are
only beginning to understand; but as I have continuously
maintained, solutions to climate change are no less complex
than the consequences. Our approach to combating climate change
cannot be shortsighted. We need to reduce our greenhouse
emissions, but we cannot do so in a way that jeopardizes our
ability to meet our energy demands or cripples our economy. Our
energy demands are rising, and running out of conventional
power plants is a real threat. We need to find solutions like
nuclear power that limit carbon emissions but also ensure that
our energy needs will be met.
We're also facing unprecedented economic challenges. As the
challenges of competing in the global economy grow, rapidly
developing countries like China and India have made it clear
that they will not hinder their economic growth to curb climate
change. I heard that repeatedly in Kyoto and Buenos Aires and
in the Netherlands. This means that any modest success that we
enjoy at limiting our emissions will be completely offset by
China and other nations. We cannot afford to stall our own
economic development when other nations will not be similarly
handicapped.
Today's hearing, like the hearing we had last month, is
focused on dire predictions relating to climate change. These
concerns are important, but we could just as easily be focused
on dire predictions about our ability to meet energy demands or
to meet the growing economic challenges of globalization. These
three challenges are deeply intertwined, and our solution to
them needs to be comprehensive and address all of them.
USGS's most recent report on polar bears and sea ice is in
some ways encouraging. While the report indicates that both sea
ice and polar bear populations will decline over coming
decades, the report does conclude that there will still be a
viable polar bear population even a century from now. It is
also encouraging that many of the problems we are facing, from
the national security implications we discussed last month to
the polar bears, sea ice, permafrost, and spruce trees we are
here to discuss today; they are all symptoms of the same
underlying problem. As we develop and implement technologies
for alternative energies, we reduce the threat from all of
these symptoms, and I am confident that we can reduce these
threats with a comprehensive approach that meets our energy
needs and strengthens our economy.
I yield back the balance of my time.
[The prepared statement of Mr. Sensenbrenner follows:]
Prepared Statement of Representative F. James Sensenbrenner, Jr.
Today's hearing takes a wide breadth--from predicted declines in
polar bear populations, to whether polar bears should be listed under
the Endangered Species Act, to melting permafrost and its implications,
to the ecological affects of climate change on spruce tree populations.
The individual topics are too complex to approach in depth in a single
hearing, but the common thread is obviously climate change and the
underlying truth that the arctic is melting.
There is obvious value in bringing the world's attention to the
problem, but we may have reached a tipping point when it comes to
raising awareness on climate change--we have the world's attention, the
question now is what we are going to do with it. As the diverse subject
matter of today's hearing suggests, climate change can have broad
effects that we are only beginning to understand.
But as I have continuously maintained, solutions to climate change
are no less complex than the consequences. Our approach to combating
climate change can not be short-sighted. We need to reduce our
greenhouse emissions, but we can not do so in a way that jeopardizes
our ability to meet our energy demands or cripples our economy. Our
energy demands are rising and running out of conventional power plants
is a real threat. We need to find solutions, like nuclear power, that
limit carbon emissions, but also ensure that our energy needs will be
met.
We are also facing unprecedented economic challenges. As the
challenges of competing in a global economy grow, rapidly developing
countries like China and India have made clear that they will not
hinder their economic growth to curb climate change. This means that
any modest successes that we enjoy at limiting our emissions will be
completely offset by China and other nations. We cannot afford to stall
our own economic development when other nations will not be similarly
handicapped.
Today's hearing, like the hearing we had last month, is focused on
dire predictions related to climate change. These concerns are
important, but we could just as easily be focused on dire predictions
about our ability to meet energy demands or to meet the growing
economic challenges of globalization. These three challenges are deeply
intertwined and our solution to them needs to be comprehensive.
USGS' most recent report on polar bears and sea ice is in some ways
encouraging. While the report indicates that both sea ice and polar
bear populations will decline over the coining decades, the report does
conclude that there will be still be viable polar bear populations even
one century from now. It is also encouraging that as many problems as
there are, from the national security implications we discussed last
month to the polar bears, sea ice, permafrost, and spruce trees we are
here to discuss today, they are all symptoms of the same underlying
problem. As we develop and implement technologies for alternative
energy, we reduce the threat from all these symptoms. And I am
confident that we can reduce these threats with a comprehensive
approach that meets our energy needs and strengthens our economy.
Chairman Miller. Thank you, Mr. Sensenbrenner. If there are
other Members who wish to submit additional opening statements,
your statements will be added to the record at this point.
[The prepared statement of Mr. Costello follows:]
Prepared Statement of Representative Jerry F. Costello
Mr. Chairman, I appreciate the Subcommittee addressing this issue
today and continuing an emphasis on matters affecting our environment.
The melting of the ice sheets and permafrost and the deterioration of
the boreal forests all have potentially severe consequences for the
Earth and scientific estimates of global climate change.
A central question we must address is how do we prepare for these
possible effects when the processes can be hard to track and the
physical properties in question are not always well understood? This
becomes very important when you consider that models to date have been
too conservative, predicting less melt than has actually occurred.
Loss of ice cover also is predicted to have a disastrous effect on
the polar bear population over the next century. I look forward to
hearing more about the consequences of ice melt and how to deal with
the uncertainty of some of these projections.
Mr. Chairman, I again commend you for calling this hearing so we
can have a better understanding of these issues. In an era of scarce
government resources, we must choose wisely how we prioritize issues
and create public policy, and this topic certainly can inform how we
view the debate on global climate change.
Chairman Miller. And now, I would like to introduce our
witnesses. Dr. Richard Alley is the Evan Pugh Professor of
Geosciences at Pennsylvania State University. Dr. Alley
appeared before the Committee to testify about the findings of
the IPCC Report earlier this year. Today he will testify about
matters including sea ice, the impact of albedo and ice sheet
melting. Dr. Glenn Juday is a Professor of the School of
Natural Resources and Agricultural Sciences at the University
of Alaska at Fairbanks, one of the world's leading centers for
the study of the Arctic. He will discuss recent climatic
changes in Alaska including those in the permafrost and what we
do and do not understand about the potential release of carbon
in the boreal forest. Dr. Sue Haseltine is the Associate
Director of Biology at the U.S. Geological Survey. She will
discuss the findings in its study on the population projections
of the polar bears for the next century. Ms. Kassie Siegel is
the Director at Climate, Air, and Energy Program at the Center
for Biological Diversity. The Center initiated a lawsuit under
the Endangered Species Act that resulted in the proposed
listing of the polar bear as an endangered species and resulted
in the USGS study. She will discuss the Center's proposed
rapid-action plan to address Arctic meltdown and to save the
polar bear.
As our witnesses should know, your full written statement
will be placed in the record; and your oral testimony is
limited to five minutes each. We will give you a little
forgiveness on that, but try to pay attention when you see the
red light come on. It is also the practice of the Subcommittee
to take testimony under oath. Do any of you have any objection
to being sworn in? I have to say it seems unlikely to me that
any testimony at this hearing would result in perjury charges,
but we do want to put you under oath. Just relax at that
prospect. And to relax you further, we also always ask if you
are represented by counsel today. You are entitled to be
represented by counsel. Do any of you have counsel today? You
are all on your own? Okay.
If you would now please stand and raise your right hand?
[Witnesses sworn]
Chairman Miller. Dr. Alley, you may begin.
STATEMENT OF DR. RICHARD B. ALLEY, EVAN PUGH PROFESSOR OF
GEOSCIENCES, DEPARTMENT OF GEOSCIENCES, PENNSYLVANIA STATE
UNIVERSITY
Dr. Alley. Thank you for the honor, Mr. Chairman. Honored
Members and guests, I have had the very good fortune to assist
the U.S. National Academy of Sciences and the Intergovernmental
Panel on Climate Change in their overarching assessments of the
issues of climate change. Those assessments have shown us with
high scientific confidence that our activities, fossil fuel
burning especially, are changing the composition of the
atmosphere, that this is changing the climate, that the changes
that have happened so far are very small compared to the
changes that will occur under business as usual, and that these
coming changes will have very large impacts on ecosystems and
economies.
This is science. It is not revealed truth. And there are of
course uncertainties related to this. Unfortunately, what we
find is that around that central estimate, things might be a
little bit better, they might be a little bit worse. We have
not yet found a lot better, but we have found the possibility
of a lot worse. That is especially linked to this issue of
abrupt climate changes or thresholds or what are now called
tipping points. And in looking at the tipping points, the
Arctic is the center of focus. I would like to mention a couple
of these; one of them is close to my own research on the
Greenland ice sheet. The Greenland ice sheet can exist in part
because it is so high left over from the ice age that the top
is cold. If you make it too warm so that you lower it enough, a
little bit of warming lowers the surface. That makes it warmer
yet. A little bit of cooling does not get you back to where you
had been, and the ice sheet is no longer survivable.
We know of no way that you can melt a Greenland ice sheet
in mere decades. It would be longer than that. But it remains
possible that we will reach a temperature over the next decade
which will cause melting of the Greenland ice sheet. Greenland
is about 23 feet vertically for the world's ocean. It would
certainly arrive much more slowly than what we saw in New
Orleans, but just as a scaling, the deepest water in New
Orleans after the hurricane was 20 feet; and so Greenland would
be more water than that for all the coasts of the world if we
tip it over.
Another tipping point that comes out of the Arctic is the
issue of changes in the North Atlantic circulation. In fact,
the IPCC said we have 90 percent confidence that that won't
happen, but 90 is not 100. We know in the past that when a lot
of fresh water was being put into the North Atlantic, sometimes
very large and surprising things happened. One of the outcomes
of those large and surprising things was a notable drying in
places where now some billions of people rely on rain-fed
agriculture. So in the unlikely event that the melt water from
Greenland should tip the North Atlantic, there are potentially
very large consequences.
The discussion you will hear coming down the line here on
sea ice, is that we have seen a reduction in sea ice. We have
seen this year a remarkable reduction in sea ice, and it is
losing the thick ice that has an easier time surviving for
years. And so the possibility exists as you shrink that sea ice
loose, the thick ice will soak up more sun because you don't
have the reflection; but we tip into a situation in which the
summertime sea ice is gone for long periods of time and hard to
get back. You will hear some of the impacts. This clearly
affects ecosystems; it opens resource exploitation; it opens
shipping; it opens coastal villages to waves that had been
blocked by the sea ice and quite a number of other changes; and
it may propagate into the climate of the lower latitudes with
possibly interesting results.
An analogy for predicting this is going to be difficult.
You know that if you sit in a canoe and you lean a little bit
that the canoe leans a little. If you lean a little more, at
some point the canoe flips. Telling exactly where the canoe
will flip is very difficult, and we can prove that because
people fall in sometimes. They can't predict that. Now, we are
changing the atmosphere, but we are changing many other things
as well, and nature certainly is out there changing things as
well. And so the analogy really should be trying to predict
when one might flip a canoe while having a large and
rambunctious golden retriever bouncing around in the boat with
you. This makes it much more difficult, and there will always
be under-certainties in these predictions.
To summarize then, we have high scientific confidence that
our fossil fuels and other activities are changing the
atmosphere, that this is changing the climate, that the changes
we have observed so far are small compared to the changes that
will come under business as usual, that this will have large
impacts on us and other living things. It will grow to be very
costly, and as has been mentioned, there are options for
solutions. This is science. It has associated uncertainties.
Unfortunately, because of the existence of tipping points and
other things, more of the uncertainty is on the bad side and
less of the uncertainty is on the good side. Thank you.
[The prepared statement of Dr. Alley follows:]
Prepared Statement of Richard B. Alley\1\
---------------------------------------------------------------------------
\1\ Any opinions, findings, conclusions, or recommendations
expressed in this publication are those of the author and do not
necessarily reflect those of the Pennsylvania State University, the
Intergovernmental Panel on Climate Change, the National Research
Council, or other organizations. My remarks neither prejudge nor
presage the contents of Synthesis and Assessment Product 1.2 of the
U.S. Climate Change Science Program, now in preparation and for which I
am one of the lead authors.
---------------------------------------------------------------------------
Changes in Arctic Ice With Special Focus on Greenland and Sea Level
Introduction
My name is Richard Alley. I am Evan Pugh Professor of Geosciences
and Associate of the Earth and Environmental Systems Institute at the
Pennsylvania State University. I have authored over 175 refereed
scientific publications in the areas of ice and climate, which are
``highly cited'' according to a prominent indexing service, and I have
given hundreds of presentations concerning my areas of expertise. My
research interests focus especially on glaciers and ice sheets, their
potential for causing major changes in sea level, the climate records
they contain, and their other effects on the environment. I have been a
member of many national and international committees, including
chairing the National Research Council's Panel on Abrupt Climate Change
(report published by the National Academy Press in 2002) and serving on
their Polar Research Board. I have contributed to the efforts of the
Intergovernmental Panel on Climate Change (IPCC) in various ways, and
served as a Lead Author on Chapter 4 (the Cryosphere), and on the
Technical Summary and the Summary for Policy-makers of Working Group I
of the Fourth Assessment Report, which was released in 2007. I
testified to the Committee in February of this year following release
of that Summary for Policy-makers; here, I will update some of that
testimony and provide special focus on the Arctic.
Ice Changes
Recent authoritative assessments from the National Research
Council, the Intergovernmental Panel on Climate Change, and other
sources have summarized the strong scientific evidence that human
activities are altering the composition of the Earth's atmosphere,
causing warming and other changes. There exists increasingly strong
evidence for widespread reductions in the Earth's ice, including snow,
river and lake ice, sea ice, permafrost and seasonally frozen ground,
mountain glaciers, and the great ice sheets of Greenland and
Antarctica, as summarized by the IPCC and elsewhere. Strong evidence
shows the dominant role of warming, which is primarily being caused by
human activities, in this loss of ice.
I will briefly summarize some of these many aspects, especially
focusing my attention on the issue of ice-sheet shrinkage and its
possible effect on sea-level rise. I will rely on my recent testimony
to the Committee, summarizing the recent IPCC report, as well as other
and more recent materials as needed.
Snow cover has decreased in most regions, as shown by satellite
data tied to limited surface observations. Snow melt is shifting
earlier into the spring. Declines in April 1 snowpack have been
measured in 75 percent of western North American sites monitored. As
summarized in the IPCC Working Group II report, concerns raised by this
decline include the dominant role now played by snowpack in supplying
summertime water to many regions of the U.S. West. Trends in snow cover
cannot be explained solely by changing precipitation (and indeed, in
some very cold places snow depth has increased with increasing
precipitation), but much of the overall shrinkage of snow cover can be
explained by rising temperature.
Freezing of rivers and lakes generally has been occurring later in
the fall, with thawing earlier in the spring, giving longer intervals
of open water. Coordinated data collection is scarce, however, and the
data set not extensive.
Arctic sea ice, formed by freezing of ocean water, has decreased in
area and thickness. The change in the summer has been especially large,
with ice lost from an area twice the size of Texas between 1979 and
2005 (decreasing trend in ice area of seven percent per decade over
that interval). Data sets from satellites, tied to observations from
ships and submarines, have been critical in documenting these changes.
An especially large loss of sea-ice area was observed during summer of
2007, pushing the late-summer minimum sea-ice area approximately 23
percent below the previous (from 2005) record minimum documented by
satellite, as reported by the National Snow and Ice Data Center (a
research institute at the University of Colorado with funding from NSF,
NASA, and NOAA). These very recent results were obtained using well-
documented techniques that have been detailed in peer-reviewed
publications; thus, while full peer-review and assessment of the latest
results are not yet completed, the results are generally considered to
be highly reliable. Although shifts in circulation of the ocean and
atmosphere may have contributed to the ongoing trend of sea-ice loss,
greenhouse gas warming is likely to have been important. (Any Antarctic
sea-ice changes fall within natural variability; cooling associated
with the ozone hole may be affecting Antarctic climate, a complex
subject beyond the scope of these brief remarks.)
Permanently frozen ground (permafrost) and seasonally frozen ground
are not readily monitored globally. However, available reports point to
overall warming and thawing of this ice in the ground, in response to
rising air temperatures and changes in snow cover.
Glaciers and ice caps occur primarily in mountainous areas, and
near but distinct from the Greenland and Antarctic ice sheets. On
average, the world's glaciers were not changing much around 1960 but
have lost mass since, generally with faster mass loss more recently.
Glacier melting contributed almost an inch to sea-level rise during
1961-2003 (about 0.50 mm/year, and a faster rate of 0.88 mm/year during
1993-2003). Glaciers experience numerous intriguing ice-flow processes
(surges, kinematic waves, tidewater instabilities), allowing a single
glacier over a short time to behave in ways that are not controlled by
climate. Care is thus required when interpreting the behavior of a
particular iconic glacier (and especially the coldest tropical
glaciers, which interact with the atmosphere somewhat differently from
the great majority of glaciers). But, ice-flow processes and regional
effects average out if enough glaciers are studied for a long enough
time, allowing glaciers to be quite good indicators of climate change.
Furthermore, for a typical mountain glacier, a small warming will
increase the mass loss by melting roughly five times more than the
increase in precipitation from the ability of the warmer air to hold
more moisture. Thus, glaciers respond primarily to temperature changes
during the summer melt season. Indeed, the observed shrinkage of
glaciers, contributing to sea-level rise, has occurred despite a
general increase in wintertime snowfall in many places.
Ice-sheet changes
The large ice sheets of Greenland and Antarctica are of special
interest, because they are so big and thus could affect sea level so
much. Melting of all of the world's mountain glaciers and small ice
caps might raise sea level by about one foot (0.3 m), but melting of
the great ice sheets would raise sea level by just over 200 feet (more
than 60 m). We do not expect to see melting of most of that ice, but
even a relatively small change in the ice sheets could matter to the
world's coasts.
A paper published in the journal Science earlier this year
(Rahmstorf et al., 2007) compared the projections made in the 2001 IPCC
Third Assessment Report to changes that have occurred. The carbon
dioxide in the atmosphere has followed expectations closely.
Temperature has increased just slightly faster than projected, but well
within the stated uncertainties. The central estimate of observed sea-
level rise is following near the upper edge of the stated uncertainties
of the expectations, however, well above the central estimate. Changes
in the ice sheets help explain this.
The 2001 IPCC report noted large uncertainties, but presented a
central estimate that the combined response of the ice sheets to
warming would be slight net growth averaged over the 21st century,
slightly reducing the sea-level rise from other sources, with increase
in total snowfall on the ice sheets exceeding increase in total melting
and with little change in ice flow. Data collected recently show that
the ice sheets very likely have been shrinking and contributing to sea
level rise over 1993-2003 and with even larger loss by 2005, as noted
in the IPCC report and updated elsewhere (e.g., Alley et al., 2007).
Thickening in central Greenland from increased snowfall has been more
than offset by increased melting in coastal regions. Many of the fast-
moving ice streams that drain Greenland (see the Figure, below) and
parts of Antarctica have accelerated, transferring mass to the ocean
and further contributing to sea-level rise. The total contribution to
sea-level rise from the ice sheets remains smaller than the
contribution from mountain-glacier melting or from the expansion of
ocean water as it warms. However, the existence of the ice-sheet
contribution, its important ice-flow source, and the large potential
sea-level rise from such mechanisms in the future motivate careful
consideration.
Ice-sheet behavior. An ice-sheet is a two-mile-thick, continent-
wide pile of snow that has been squeezed to ice. All piles tend to
spread under their own weight, restrained by their own strength (which
is why spilled coffee spreads on a table top but the stronger table
beneath does not spread), by friction beneath (so pancake batter
spreads faster on a greased griddle than on a dry waffle iron), or by
``buttressing'' from the sides (so a spatula will slow the spreading of
the pancake batter). Observations at a site in Greenland have shown
that meltwater on top of the ice sheet flows through the ice to the
bottom and reduces friction there. More melting in the future thus may
reduce friction further, speeding the production of icebergs or
exposing more ice to melting from warmth at low altitude, and thus
speeding the increase in sea level.
Some early gothic cathedrals suffered from the ``spreading-pile''
problem, in which the sides tended to bulge out while the roof sagged
down, with potentially unpleasant consequences. The beautiful solution
was the flying buttress, which transfers some of the spreading tendency
to the strong Earth beyond the cathedral. Ice sheets also have flying
buttresses, called ice shelves. The ice reaching the ocean usually does
not immediately break off to form icebergs, but remains attached to the
ice sheet while spreading over the ocean. The friction of these ice
shelves with local high spots in the sea floor, or with the sides of
embayments, helps restrain the spreading of the ice sheet much as a
flying buttress supports a cathedral. The ice shelves are at the
melting point where they contact water below, and are relatively low in
elevation hence warm above. Ice shelves thus are much more easily
affected by climatic warming than are the thick, cold central regions
of ice sheets. Rapid melting or collapse of several ice shelves has
occurred recently, allowing the ``gothic cathedrals'' behind to spread
faster, contributing to sea-level rise. Many additional ice shelves
remain that have not changed notably, and these contribute to
buttressing of much more ice than was supported by those ice shelves
that experienced the large recent changes, so the potential for similar
changes contributing to sea-level rise in the future is large.
Although science has succeeded in generating useful understanding
and models of numerous aspects of the climate, similar success is not
yet available for ice-sheet projections, for reasons that I would be
happy to explore with the committee. We do not expect ice sheets to
collapse so rapidly that they could raise sea level by meters over
decades; simple arguments point to at least centuries. However, the
IPCC report is quite clear on the lack of scientific knowledge to make
confident projections. Naive comparison of tabulated projections of
sea-level rise in the Third and Fourth Assessment Reports of the IPCC
might lead a reader to the mistaken conclusion that the more-recent
assessment has reduced uncertainties and concerns about sea-level rise.
However, the newer report specifically notes that projections exclude
contributions to sea-level change from ``future rapid dynamical changes
in ice flow'' (Table SPM-3) ``because a basis in published literature
is lacking'' (page SPM14), so that it is not possible to ``provide a
best estimate or an upper bound for sea level rise'' (page SPM15). (The
new report also notes a similar difficulty arising from lack of
knowledge of feedbacks in the carbon cycle, and referring to the
possibility that warming will cause much release of methane and carbon
dioxide from soils in the Arctic, sediments under the sea, or
elsewhere, contributing to more warming.)
Much discussion has focused on the question of ``tipping points''
or thresholds for abrupt change. Clearly, at sufficiently warm
temperatures, ice will melt. As discussed in the IPCC report,
sufficiently warm temperature, sustained for a sufficiently long time,
will melt the Greenland ice sheet, with more than a few degrees of
warming sustained over a few centuries to millennia being a reasonable
approximation but with no agreement on exact values. This is often
considered to represent a tipping point because a small cooling then
would not restore the ice sheet even if sustained for a long time; the
warming associated with the loss of the high-elevation and reflective,
hence cold, ice surface would overcome any small subsequent cooling.
Recent simple modeling (e.g., Schoof, 2007; also see Dupont and Alley,
2005) supports earlier work that ``tipping point'' behavior might be
observed in Antarctica as well, with warming sufficient to weaken or
remove certain ice shelves triggering ice-sheet changes to a new state.
These processes remain very poorly understood, and confident assessment
of their likelihood or rate is not now possible.
Synopsis
In summary, with high scientific confidence, changes are occurring
in much of the world's ice. These are being caused primarily by
warming. Globally, the warming is largely being caused by greenhouse
gases being released to the atmosphere by human activities. Shrinkage
of the large ice sheets was unexpected to many observers but appears to
be occurring, and the poor understanding of these changes prevents
reliable projections of future sea-level rise over long times.
Recently published estimates of the mass balance of the Greenland ice
sheet through time (modified from Alley et al., 2007). A Total Mass
Balance of 0 indicates neither growth nor shrinkage, and -180 Gt
yr-1 indicates ice-sheet shrinkage contributing
to sea-level rise of 0.5 mm/year (one inch in about 50 years), as
indicated. Each box extends from the beginning to the end of the time
interval covered by the estimate, with the upper and lower lines
indicating the uncertainties in the estimates. A given color is
associated with a particular technique, and the different letters
identify different studies. Two estimates have arrows attached, because
those authors indicated that the change is probably larger than shown.
The dotted box in the upper right is a frequently cited study
(Johannessen et al., 2005) that applies only to the central part of the
ice sheet, which is thickening, and misses the faster thinning in the
margins.
References Cited
Alley, R.B., M.K. Spencer and S. Anandakrishnan. 2007. Ice-sheet mass
balance: Assessment, attribution and prognosis. Annals of
Glaciology 46, 1-7.
Dupont, T.K. and R.B. Alley. 2005. Assessment of the importance of ice-
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Biography for Richard B. Alley
Dr. Richard Alley is Evan Pugh Professor of Geosciences and
Associate of the Earth and Environmental Systems Institute at The
Pennsylvania State University, University Park, where he has worked
since 1988. He was graduated with the Ph.D. in 1987 from the University
of Wisconsin-Madison and with M.Sc. (1983) and B.Sc. (1980) degrees
from The Ohio State University-Columbus, all in Geology. Dr. Alley
teaches, and conducts research on the climatic records, flow behavior,
and sedimentary deposits of large ice sheets, to aid in prediction of
future changes in climate and sea level. His experience includes three
field seasons in Antarctica, eight in Greenland, and three in Alaska.
His awards include the Seligman Crystal of the International
Glaciological Society, the first Agassiz Medal of the European
Geosciences Union Cryospheric Section, a Presidential Young
Investigator Award, the Horton Award of the American Geophysical Union
Hydrology Section and Fellowship in the Union, the Wilson Teaching
Award and the Mitchell Innovative Teaching Award of the College of
Earth and Mineral Sciences and the Faculty Scholar Medal in Science at
Penn State. Dr. Alley has served on a variety of advisory panels and
steering committees, including chairing the National Research Council1s
Panel on Abrupt Climate Change, and has provided requested advice to
numerous government officials in multiple administrations including a
U.S. Vice President, the President's Science Advisor, and a Senate
Committee. He has published over 170 refereed papers, and is a ``highly
cited'' scientist as indexed by ISI. His popular account of climate
change and ice cores, The Two-Mile Time Machine, was chosen science
book of the year by Phi Beta Kappa in 2001. Dr. Alley is happily
married with two children, two cats, and two bicycles, and resides in
State College, PA, where he coaches recreational soccer and
occasionally plays some.
Chairman Miller. Thank you, Dr. Alley. A better analogy
might have been a Labrador retriever.
Dr. Juday.
STATEMENT OF DR. GLENN PATRICK JUDAY, PROFESSOR OF FOREST
ECOLOGY, SCHOOL OF NATURAL RESOURCES AND AGRICULTURAL SCIENCES,
UNIVERSITY OF ALASKA AT FAIRBANKS
Dr. Juday. Thank you. I just want to point out at the
beginning that I am bringing information that was requested
from Vladimir Romanovsky and John Walsh as well who are
specialists respectively in permafrost and sea ice, and I will
try not to misconstrue the information that comes from
publications that I have cited in the presentation; and if
there are more detailed questions, I can certainly have them
respond if it goes beyond my expertise. I am the frost guy.
First, on permafrost, permanently frozen ground or at least
ground that has remained in a frozen state for two years
underlies a significant part in the northern portion of the
planet and in certain places can contain large lenses of pure
water ice but a lot of frozen organic material. We have
recognized three kinds of permafrost, the continuous permafrost
in the coldest portion; the discontinuous permafrost where the
temperatures are marginal, and local, side factors take over
the determination of whether you are going to stay in the
frozen condition or not; and then in the southernmost extent,
only the very coldest spot localities in the landscape have
permafrost.
Permafrost temperature measurement has not been a big field
in science, and very few people have done that work. Dr.
Romanovsky is one of them and taking over some early work done
by Dr. Tom Ostercamp.
Here you see a plot of the actual frozen ground temperature
trends since the late 1970s, so we have about a 30-year
perspective. The trend is up. Equations that predict the
temperature of permafrost work exceptionally well with just a
few input factors, air temperature obviously is one of them,
but snow cover is an extremely important one. And we have seen
a very strong rise and then a kind of leveling or even a
backing off a little bit because of a trend toward decreasing
snow cover. All the models say more snow cover under the
warming Earth, and all the data say--not quite all the data but
a significant number of stations, they have had less.
Here is a depiction of nearly a century worth of air
temperature data from Central and Southcentral Alaska. You see
that permafrost forms in the region when the mean annual
temperature is between 0+C/32+F and -2,
and you see that in the Talkeetna area in Southcentral Alaska
with the decisive move of temperatures about 30 years ago in
the regime shift, we are completely out of that zone. And in
Central Alaska, in Fairbanks, about half of all years are spent
in the zone where at least some thawing will begin.
So what does this mean? Just allowing for not an
acceleration but a continuation of recent trends in
temperatures, the red areas depicted here would be those that
would thaw ultimately. Again, there is a long lag effect
because there is a lot of insulation power in that material
that is on the ground, and it goes some depth into the ground;
but the initiation of thawing would begin in the areas depicted
there.
Now, so what? Big deal. Who cares? Well, it is a big deal
for a couple of things. Linear infrastructure is the thing most
at risk, railroads, roads, pipelines, because you have to get
from point A to point B, and avoidance is not an option. So
that means you got to deal with it. It can be engineered, but
it is going to cost. Some structures, such as the pipeline,
advance the technology of dealing with permafrost with natural
convected cooling fans and things, but those were designed for
again, mean annual temperature. They are engineered for it and
achieving a certain amount of cooling and a careful look may
need to be paid at the design capacity of those systems.
Now buildings and building footprints on permafrost can be
a significant problem. If the building is small and low value
enough, maybe a low-cost solution like just adjustable
foundations can work. In other cases, if you are going to put a
major investment in the ground, you are dealing with probably
something else entirely.
Now, perhaps of more global significance is the role that
thawing the permafrost is going to have in releasing as you
pointed out, Mr. Chairman, the greenhouse gases into the
atmosphere. Spontaneous thaw of permafrost is observable on the
landscape today as you can see. It can come out in two
different forms, one, CO2 when the decomposition is
aerobic, but it can also come out as methane when the
conditions are anaerobic. And as lenses of ice thaw and then
melt, the ground subsides, fills with water, creates anaerobic
conditions, lack of oxygen, what comes out is methane. It
generally has been vastly underestimated in the past, and the
reason is it comes out in a way that is hard to measure, and
that is these bubbles.
Here you see the bubbles trapped in clear water ice. That
methane of course is an extremely powerful greenhouse gas, and
per unit volume is 21 times more powerful in producing a
greenhouse effect.
This, now, collapsed ponds and efoliation or bubbling up of
methane is a widespread phenomenon observable in parts of
Alaska and in Siberia.
So what does this all mean? Let us get some numbers on the
table here. As you pointed out, gigatons of carbon per year.
Recent years we have been combusting about 6.3. Essentially
permanent land use change in the tropical forest regions has
been usurping the uptake so that we get 7.9. However,
fortunately for us, uptake in storage on land has been about
2.3 and similar amount in the world ocean, so that the net
problem that we experience is an uptake of 3.3, which is
considerably less than the 7.9. I am afraid I have to tell you
that there is every indication that the ability of land
ecosystems to store carbon is going down and probably down very
significantly, and they may very soon be net neutral.
Now, in terms of storage, it is just a slightly different
story. The tundra and the boreal systems are pretty good at
growing plant material but really not so good at decomposing it
because of the cold soils. The tropical forests are some of our
most productive systems on the Earth, that is uptake of carbon,
but they decompose just about the same amount, very low
storage. So in that storehouse, that locker of carbon that
makes up the ground layer in the cold regions, we are seeing
some very momentous developments. For example, we had a
September tundra fire, extremely rare event; and it was not a
small one, it was a very, very large one. It was over 175,000
acres.
You can see the footprint of the fire on the north slope of
Alaska here. We have a reasonable record of wild land fire in
Alaska for 57 years, and the record is not being kept according
to the fuel type that burned, whether it was tundra or whether
it was forest; but I asked the Alaska Fire Service, and they
produced this statistic. If you draw a line at 68 North, north
of that there just generally aren't forests. So let us focus on
that, and we will be sure that we are getting a tundra single.
This is as clear as the evidence gets. There were no tundra
fires. Then came a period when at peak warmth we had one, two,
and now a very substantial increase in tundra fire.
Now, let us transition a little further south of the boreal
forest, that is that belt of conifer-dominated forest land
south of the tundra. It has this tilt to it, so that in the
western North American boreal is further north and more
productive in equivalent latitude than in eastern North
America, and that is because of the introduction of warm air
from the south by the storm systems and its export with a
little boost from the cold ice regions of eastern North
American Arctic.
This is a graphic I actually produced for the Select
Committee that I testified to two weeks ago. We were going to
this stand when we had to cancel the trip this summer but did
have the hearing, and in that stand that I have been monitoring
for 20-some years, I just plotted the predictive index of
temperature that tells us how much the forest should grow
versus the ring width, which is the vertical axis there of this
sample. And you can see that warmer, the less it grows. The
interesting thing is where the index doesn't work for example,
the forest grew less than the prediction. There is a good
reason for that, for example, spruce bud worm outbreaks, the
trees covered with volcanic ash.
Here is our record-warm summer, 2004, which predicted the
growth in 2005; and you see there is a zone of uncertainty
around the trend line which means that we are extremely close
to what you could call the kill zone, lethal temperatures,
where the trees would spontaneously die in the forest because
it is just too warm for their adaptive capabilities. You can
see that is about one degree C.
Now, is that a local phenomenon? Is that just something I
found in my plot in my course?
This is a satellite observed, photosynthetic trends
measured from 1980 through 2003 by Scott Goetz, and these are
pixels depicted here, 10-by-10 kilometer chunks of the Earth;
and if during that period of time the photosynthetic trend was
down or strongly down, it is colored blue, and as you can see,
the entire boreal forest of North America shows considerable
amount of blue or neutral--no large increases.
We are seeing things for example the spruce bud worm now
exhibiting outbreak behavior. It is an insect that hatches,
feeds on the foliage like this, and leaves the tree in this
condition after it is done feeding, and there is a direct
temperature control. It is a major insect species in the
Canadian boreal forest. We have never seen it in outbreak mode
in the northernmost boreal forest. Now it is. Temperatures were
too low, now they are warm enough, now it is killing the trees.
You can see clearly a record in tree growth. There is the
2005 hot, dry year. There is the spruce bud worm outbreak. This
is killing the growth of the forest. But that is not all. There
is leaf scorch on birch trees. It is the last symptom to appear
before the tree dies and when it is running out of water. A
three-tone color in which there is death or necrosis of tissue
around the margin and the breakdown of chlorophyll so that you
have the yellow zone, and finally, the green is retained only
around the veins where the water can be first introduced into
the leaf. Similar kill zone is apparent in our most sensitive
sites that grow birch, and in fact, of the 2004 temperature
indicating, well, we entered the kill zone. So do we have dead
trees? Yes. Head of the Forest Health Survey took my research
seriously, and so he went out and he looked and he found dead
trees that were not killed by insects that apparently were the
result of this phenomenon.
Fires, we had the record fire year in the season 2004. If
you take the northeast quadrant of Alaska, 15 to 20 percent of
all forest land burned in one year. Then something very close
to that happened the next year, another seven to 10 percent. So
in a two-year period, we had one-fourth to one-third of all
forest land in the northeast quadrant of Alaska burned.
Finally, I will just do a couple of comments about sea ice
that is going to be the subject of a lot of discussion from a
couple perspectives here.
This is the depiction of the sea ice cover as of I think it
is a week-and-a-half ago. You see the long-term mean in the
upper black line. The dashed line was the previous record low,
the 2005 record, and you see 2007, 25 percent below the
previous low record which was set only two years ago.
Here is a depiction of the seasonal and annual sea ice
extent. There are two different standards for measuring this.
In case there is some confusion in some of the numbers thrown
around, just be aware of that. There is this sea ice edge, and
there is also total sea ice cover, which accounts for leads and
openings further north but as you can see, a radical reduction
in a one-year period in the sea ice cover at the end of the
summer.
And perhaps as significant, there are these zones of
retreat that rotate around along with the movement of the ice
in the polar gyre that have brought open water conditions very
far north in the past but usually in a lobe or a finger in one
particular sector of the arctic. But during the period of the
satellite record, no open water has ever been seen in the area
depicted here, and that was entirely free of ice and contiguous
with other open water all the way to the south.
The last point I will make is a little community of
Shishmaref, you may have heard of it, had the opportunity, in
the hearing two weeks ago, to be accompanied by Mayor Stanley
Tocktoo who is mayor of this community, and just to give you a
picture of what they are dealing with, these are self-reliant
people who work hard. They engage in hard, physical labor, not
for cash but for a considerable period of the year to get the
food they need. They go out on the ice to hunt. They gather,
they fish, they engage in these activities; and they can tell
you, their environment is changing. Pack ice should be
presenting and forming right about now; it traditionally has
been, giving them access to the seals they hunt and a very
important part of their annual diet; and they are not able to
be safely on the ice at this time.
For example as you see here in February and the erosion
that is now possible from the storm and the fetch that the wind
has access to churn and push this water because of the
disappearance of the sea ice is causing enormously accelerated
erosion, and the community is literally being destroyed.
So in summary, the permafrost definitely is warming. The
first stages of thawing are obvious. The boreal forest has
burned, is sick, or is dying on a very extensive scale. Its
ability to store carbon is being severely compromised, and
immobilization of carbon that has previously been stored is
well under way. Sea ice is treating and also thinning. I have
touched on other things such as glacier melting, sea level
rise, lakes drying, species movements, etc., but if you have
questions on those areas, I will attempt to answer them. Thank
you.
[The prepared statement of Dr. Juday follows:]
Prepared Statement of Glenn Patrick Juday
with assistance by
Vladimir Romanovsky, Professor of Geophysics, UAF
John Walsh, President's Professor of Climate Change, UAF
F. Stuart Chapin III, Professor of Ecology, UAF
Stanley Tocktoo, Mayor of Shishmaref
Climate Change in the Alaskan Arctic and Subarctic: A Vast Panorama of
Comprehensive Environmental Change
Mr. Chairman and Members of the Committee, I would like to thank
you for the invitation to present some information to the Committee
concerning recent climatic changes, their current effects, and the
likely future situation in the Arctic and Subarctic. I have been
assisted in preparing my presentation by senior colleagues at the
University of Alaska in subjects related to climate change of interest
to the Committee.
I have had the opportunity to work with these colleagues in teams
involved in integrated climate change assessment, and they have
provided publications and data for this presentation. I have attempted
to restrict my characterization of their findings to these sources, but
if further clarification is required I will convey the issues back to
them for a definitive response.
I also recently had the opportunity to accompany Mayor Stanley
Tocktoo in recent meetings and testimony before Congress, and he
generously shared information from the presentation he used which was
assembled by the community of Shishmaref, Alaska.
The focus of my presentation is the American portion of the
Arctic--in Alaska. For a comprehensive review of the whole region,
especially the background setting and processes of this unique part of
the world, I refer the Committee to the Arctic Climate Impact
Assessment:
www.acia.uaf.edu
This written statement is meant to accompany the PowerPoint
presentation I have provided the Committee, which has maps, graphics,
citations, and other specific details.
1. Permafrost.
One of the unique features of the Arctic and Subarctic regions is
the extensive presence of cold soils and permafrost. Permafrost is soil
and ground material that remains frozen for more than two years.
Permafrost forms when mean annual temperatures are below freezing,
generally in the range of 0 to -2 degrees C. Differences in soil
texture, water content, and site characteristics can allow permafrost
to form at annual temperatures equal to freezing, or require annual
temperatures well below freezing. Permafrost everywhere disappears at a
great enough depth where heat from the geothermal gradient overcomes
cold surface temperatures. Permafrost (the frozen material itself)
occurs at a range of temperatures from near 0 degrees C to ten or more
degrees below. As a result, the coldest regions make up a continuous
permafrost zone across the landscape. Slightly warmer cold regions are
within the discontinuous permafrost zone, where occurrence of the
frozen state is influenced by local factors. Areas with only isolated
or sporadic masses of permafrost make up a third zone.
Permafrost can be ice-rich, in which case thawing melts the frozen
water content and causes ground subsidence, or it can be dry, leading
to little potential for surface change between the frozen or thawed
condition. Temperature trends in permafrost are increasing clearly, and
across nearly all the Arctic and Subarctic. Permafrost temperatures are
in exceptionally close agreement with predictive models of mean annual
air temperature, snow depth and duration, and soil composition.
Reliable permafrost temperature measurements generally date back only
to about 1970, although the predictive models can be run backward in
time with good confidence. Observations of permafrost thawing at its
southernmost limits in the U.S., Canada, and central Asia are
widespread.
Surface-disturbing activities, such as road and building
construction, and natural events such as wildfire, can tip the thermal
equilibrium toward thawing in warmer permafrost regions, and have for
some time. But these processes are producing more widespread effects in
recent warmer conditions. All the permafrost in central Alaska has been
trending upward in temperature, and now nearly all of it is only -0.5
to -2.0 degrees C. Annual air temperatures above freezing are now
occurring across large portions of the permafrost regions, and are
certain to thaw the permafrost if sustained. The only questions are
exactly where (the sequence of microsites) and how fast. Calculations
indicate that a substantial fraction of existing permafrost has started
or will start the thaw process (which may take decades or centuries to
complete to the greatest depths) in the next several decades.
Linear infrastructure (roads, pipelines, railroads, etc.) are at
most risk from thawing permafrost, because such developments must
proceed from point A to point B at some location, making avoidance of
permafrost unworkable. Developments and structures can be engineered to
minimize thaw or even keep ground material frozen. But such engineering
features are substantial costs and are not easily retrofitted.
Permafrost and other cold soils hold an amount of carbon that, if
it were entirely combusted, would double atmospheric CO2
content. Warming and/or thawing of the cold or permafrost soils is
beginning to move this carbon into the atmosphere in a variety of ways.
Some of the largest wildland fires or burning seasons on record
have occurred in the Arctic and Subarctic in direct response to
increasing temperatures and drying.
2. Boreal Forest.
About half of the world forest area has been converted to other
land uses on a long-term or essentially permanent basis. The boreal
forest is the most stable by far of all the world's forest regions in
terms of forest conversion or destruction. Until recently the boreal
forest has also been the most ecologically intact of the world's forest
regions. These characteristics and the substantial annual surplus of
growth (which removes carbon from the atmosphere) compared to
decomposition (which releases carbon to the atmosphere) made the boreal
forest one of the key land areas of the world in naturally reducing the
buildup of greenhouse gasses.
Now, a variety of high temperature-related stresses have become
pervasive in much of the boreal forest, especially in Alaska, seriously
affecting its ability to continue to store carbon at the same levels as
the past.
Measurement of tree-ring growth versus temperatures over the last
century or so have shown that many trees on many site types
consistently grow less in the warmer years and grow more in the cooler
years. This negative response to warming has only been appreciated for
the last decade or so, and it has been shown to be a consequence of
high temperature-caused lack of water that induces plant shut-down.
Because the temperature increases during the last few decades in
central Alaska have been among the greatest on the planet, the tree
growth reduction effect has been considerable. Temperatures that
consistently predict the growth of trees in boreal Alaska are
approaching lethal limits. During the record warm summer of 2004 and
2005, some tree death from drought appears to have occurred in
populations of Alaska birch.
High temperatures also trigger outbreaks of forest-damaging or
forest-killing insects. Outbreaks of known or suspected high
temperature-related insects have occurred simultaneously across boreal
Alaska and now much of western Canada.
Finally, wildland fires have increased to record levels and burned
one-fourth to one-third of all forest land in the northeast (hottest
and driest summers) quarter of Alaska.
3. Arctic Sea Ice.
Arctic Ocean sea ice is a complex and dynamic phenomenon. A variety
of physical processes occur as sea water nears freezing temperatures,
changes from the liquid to the solid state, and coalesces into larger
scale structures.
Of key biological importance is the expansion of water to maximum
density at four degrees C, which then causes sinking in the water
column to the bottomwater at that temperature. The sinking action
forces or displaces older, nutrient-rich bottomwater upward, allowing a
bloom of marine productivity during the time of year that sunlight is
available. Ice crystal and structures themselves serve as secure
attachment point for specially adapted algae, with is another unique
source of marine production in these cold waters compared to the rest
of the world ocean.
The Arctic is the world's most land-dominated ocean. Several
northward-flowing rivers transfer relatively large amounts of heat,
freshwater, and nutrients into the ocean. The result of all the
processes promoting productivity is a highly productive marine
ecosystem in the northern, ice-edged seas, in distinct contrast to the
level of annual production in nearby land ecosystems. It is no co-
incidence at all that the cultures and current activities of the native
people of the Arctic are highly oriented to hunting the abundant marine
mammals, birds, fish, and other resources of the productive continental
shelves and shores of their homeland.
During the strong global warming (probably due to orbital
influences on the amount of solar energy reaching the far north) that
decisively ended the last ice age starting about 12,000 years ago, a
period of seasonally ice-free Arctic Ocean occurred probably about
8,000 years ago. A gradual cooling began between 6,000 years ago, and
continued with irregular warm periods, until the last century.
Comprehensive satellite-based records of the mount of sea ice start
in the late 1970s. But the orientation of the Arctic residents and
harvested resources toward the sea, visiting fleets, and records from
explorers and the early scientific era give a good picture of the
extent and location of sea ice for the last century and a half, with
trends and low precision before, and very high precision for the most
recent 30 years.
Changes in sea ice that are unique in the last several centuries
have appeared suddenly and extremely strongly in the last five years,
culminating in an extreme record of ice disappearance in September
2007. Influx of warmer Atlantic and Pacific Ocean bottom water,
expulsion of multi-year ice, ice thinning, coating of the ice with
small, dark soot particles, and cycles of atmospheric currents all
played a role in the recent disappearance of Arctic sea ice. But the
feedback influence of converting sunlight-reflective ice with sunlight
absorbing open water on over huge areas of the Arctic Basin, represent
one of the strongest feedbacks to global temperature increases in
recent times of the planet. This change is not likely to be reversed
soon.
As I am sure the Committee is aware, a whole new set of strategic
international relations has appeared as a result of the Arctic Ocean
now becoming navigable to ordinary marine vessels. The residents of the
Arctic now have a more difficult time gaining access to harvestable
food resources on stable or predictable ice platforms. The lack of
near-shore ice may be reducing local marine productivity by putting the
ice edge over deep water. Finally, the existence of large areas of open
water allows more frequent and stronger storms to batter the shore
which is devoid of ice protection. The resulting extreme acceleration
of shoreline erosion is displacing people of the region.
I thank the Committee for focusing on these historic, rapidly
unfolding, and powerful events, and I offer to assist Members in
obtaining additional information.
Biography for Glenn Patrick Juday
Glenn Patrick Juday, is Professor of Forest Ecology and Director of
the Tree-Ring Laboratory in the School of Natural Resources and
Agricultural Sciences at the University of Alaska Fairbanks, where he
has worked since 1981. Dr. Juday is currently a Senior Investigator in
the NSF-supported Bonanza Creek Long-Term Ecological Research site in
central Alaska. His research specialties include climate change, tree-
ring studies, biodiversity and forest management, and forest
development following fire. He is the Lead author of the chapter on
Forests and Agriculture of the Arctic Climate Impact Assessment, and a
contributing author to the chapter on Biodiversity Conservation. Dr.
Juday has served as science advisor for several U.S., Asian, and
European television programs on climate warming, including the PBS
series Scientific American Frontiers His research results were
discussed in two issues of National Geographic magazine in 2004. He has
briefed and led trips for several Members of Congress. Dr. Juday was
recognized for outstanding accomplishments as Chairman of Forest
Ecology Working Group of the Society of American Foresters in 2000. He
is the author of over 30 scientific peer-reviewed journal articles and
book chapters including Nature, Climatic Change, Global Change Biology,
Forest Ecology and Management, and Canadian Journal of Forest Research.
He has book chapters published by Oxford University Press, Cambridge
University Press, and Annual Review of Ecology and Systematics.
Dr. Juday received his B.S. summa cum laude, in 1972 in Forest
Management from Purdue University, and his Ph.D. in 1976, in Plant
Ecology from Oregon State University. He completed a Rockefeller
Foundation Post-Doctoral Fellowship in Environmental Affairs, 1976-1977
serving as Executive Chair of the Oregon Natural Area Preserves
Advisory Commission. He spent a sabbatical in the headquarters of The
Nature Conservancy in Arlington Virginia in 1988.
Chairman Miller. Thank you, Dr. Juday. I did not want to
interrupt that because it is obviously important, but if you
would try to summarize some of your testimony, it would be
helpful to the Committee.
Dr. Haseltine.
STATEMENT OF DR. SUSAN D. HASELTINE, ASSOCIATE DIRECTOR FOR
BIOLOGY, U.S. GEOLOGICAL SURVEY, U.S. DEPARTMENT OF INTERIOR
Dr. Haseltine. Thank you, Mr. Chairman, and Members of the
Subcommittee for the opportunity to participate in today's
hearing. I would also like to introduce one of our sea ice
researchers from Alaska, Dave Douglass, sitting behind me. Dave
was a member of the team that produced the reports that I am
going to talk about today.
Global climate change is one of the most complex
environmental challenges obviously facing society today. And
while climate change is a natural, continuous Earth process,
changes to the Earth's climate are also related to human
activities; and whether the causes are natural or from human
influence, the USGS scientists focus on understanding the
impacts of climate change and potential adaptive strategies for
managing natural resources and ecosystems in the face of these
changes on the landscape.
The USGS conducts scientific research to understand the
likely consequences of climate change using three primary
strategies, first by studying how climate has changed in the
past and using the past to forecast responses into the future,
second by distinguishing natural and human-induced changes
where possible, and third by quantifying both biological and
physical responses to climate change.
Today I want to discuss the changes that have been observed
and modeled in Arctic sea ice and their impacts on the top
predator in that environment, the polar bear. Data from the
satellite record for the past three decades shows a decline of
about 10 percent per decade in the minimum annual sea arctic
sea ice extent at the end of the summer melt season; and in
this year's melt season, as has been noted, the minimum ice
coverage in the Arctic was measured at about four million
square kilometers, and that represents about 40 percent less
ice than was observed in 1979 when we had the first satellite
records.
While rising Arctic air temperatures have certainly
contributed to this loss of sea ice, there are several other
factors that have interacted to accelerate the loss, and there
is a growing scientific concern that the synergism of recent
events in the Arctic, regardless of their origin, may have
already pushed the Arctic past a threshold of cascading change.
The USGS and our partners around the Arctic have a robust
baseline of data for assessing polar bear populations, for
defining essential polar bear habitat in the sea ice, and for
making projections of future population status. The nine
recently released USGS reports build on this history of
research and collaboration and culminate in a new range wide
forecast of polar bear status under various projections of
future climate change. To forecast the status of polar bear
population worldwide during the 21st century requires modeling
information on the future habitat conditions for polar bears
and also on their projected population status. We used ten of
the general circulation models that were used in the IPCC
Fourth Assessment Report in projecting this change, and those
ten were the ones that most closely mirrored the sea ice change
that we have observed over the last few decades.
We used middle-of-the-road carbon loading scenarios in
making our projections, and we developed a future model then
that combined information about annual and seasonal sea ice
change, habitat preferences for polar bears, and population
demographics to predict likely polar bear numbers and
distributions into the future. The model results show that by
the mid-century polar bear populations will likely be
extirpated from their southernmost range in southeastern
Canada, as well as from the Arctic regions bordering Alaska,
Russia, and Europe. By late century, populations in east
Greenland and the North Beaufort Sea will also likely be gone.
And as stated before, these regions now support two-thirds of
the worldwide population of polar bears, which is estimated at
between 20,000 and 25,000 animals.
However, the models also predict a strong likelihood of
polar bears surviving in the high Canadian Arctic, which may
provide a source of animals to reestablish former ranges if the
Arctic's sea ice environment is restored to present conditions.
Preliminary USGS analysis of other carbon loading scenarios
indicate that less atmosphere carbon dioxide loading does not
substantially change outcomes for polar bears through the mid-
century but does result in less loss of sea ice and thus polar
bear habitat by the end of the 21st Century.
At the USGS we recognize that the momentum of atmospheric
greenhouse gas loading will challenge us with climate-related
issues for at least the next 50 years. A better understanding
of sea ice must be combined with an understanding of ecological
response and adaptation to provide the best information to the
decision-makers. We believe that outputs from coupled physical
and biological forecasting approaches, as presented in our
recent reports, will better inform decision-makers as they
address climate adaptation. Such forecasting will require
continued long-term monitoring of both sea ice and ecological
response, focused studies of ecological processes in response
to climate change, and the application of many new and emerging
modeling approaches by science with many different specialties
working together.
Thank you for the opportunity to present and address you
today.
[The prepared statement of Dr. Haseltine follows:]
Prepared Statement of Susan D. Haseltine
Mr. Chairman and Members of the Subcommittee, thank you for the
opportunity to participate in today's hearing to discuss emerging
insights into the present and potential influences of climate
variability and change on resources of interest to the American people.
My name is Dr. Susan D. Haseltine, and I am the Associate Director for
biology at the U.S. Geological Survey (USGS).
Global climate change is one of the most complex and formidable
environmental challenges facing society today. While climate change is
a natural, continuous Earth process, changes to the Earth's climate are
related to human activities as well. Whether the causes are natural or
from human influence, our focus is on understanding the impacts of
climate change and the potential adaptive strategies for managing
natural resources and ecosystems in the face of these changes.
Today, one need only turn to the Far North to witness the emerging
signature of climate change. In Arctic and subarctic regions, the
shrinking extent of and structural changes in sea ice and permafrost
are a strong and visible signal of contemporary change in the Earth's
climate system. Sea ice controls its associated ecological systems:
From oceanographic patterns through the food chain to ice seals and
polar bears, the Arctic marine world is tied to the dynamics of sea
ice. I will focus my remarks on the realm of sea ice and recent
publications by the USGS on this environment and its top predator, the
polar bear. It should be recognized that this important work is part of
a broad body of research carried out by other federal agencies and
nations around the Arctic.
Data from the observed record document a recent history of change
in Arctic sea ice. Observations from the available satellite record
(1979-2007) show a decline of 10 percent per decade in the minimum
annual Arctic sea ice extent (end of summer melt season). That decline
is punctuated by this year's (2007) melt season, which reduced the
minimum ice cover in the Arctic to just over four million square
kilometers--as compared to the 7-8 million square kilometers observed
at the beginning of the satellite record (1979-1980). The 2007 melt
season thus reflects a roughly 40 percent reduction in ice extent from
the 1979-2000 average. Even more significant is the degree to which the
year 2007 surpassed the previous sea ice loss record of 2005--by about
one million square kilometers.
Owing to the influential role that sea ice plays in Earth's climate
system, numerous institutions and agencies worldwide (including the
USGS) are conducting research to better understand the mechanisms and
trajectory of sea ice change. The USGS is an active collaborator in
this arena. Complementing the extensive amount of research supported by
the National Science Foundation, NASA, NOAA and others, the USGS is
helping to define an emerging understanding of the changes in ice age
structure and the relationships of those trends to atmospheric
circulation patterns, thermal forcing, and other controlling
mechanisms. While rising Arctic air temperatures have certainly
contributed to the loss of sea ice, several other factors have
interacted to accelerate the loss. Changes in prevailing wind patterns
(Maslanik et al., 2007) have caused much of the older and thicker sea
ice to drift out of the Arctic Ocean (Rigor and Wallace, 2004;
Belchansky et al., 2005), leaving behind a younger and thinner ice pack
that is more vulnerable to the summer melt season. Concurrently, warmer
ocean water has been entering the Arctic from both the Atlantic
(Polyakov et al., 2007) and Pacific (Woodgate et al., 2006). A warmer
Arctic Ocean further reduces the air-water temperature gradient, which
suppresses winter ice growth (thickening) and renders it more
susceptible to summer melt. And finally, onset of the Arctic melt
season has been getting earlier (Belchansky et al., 2004; Stroeve et
al., 2006). Earlier springs trigger an earlier start to an important
positive feedback loop that begins when the bright surface of the ice
darkens from the presence of melt ponds and open water, the darker
surfaces warm faster because they absorb more solar radiation, and the
warmth promotes more melt--and so on. To what degree natural climate
variability has exacerbated the recent loss of sea ice is not well
understood. However, there is growing scientific concern that the
synergism of recent events, regardless of their origin, may have
already pushed the Arctic past a threshold of cascading change (Lindsay
and Zhang, 2005; Serreze and Francis, 2006).
The USGS is well poised to address the implications of ecological
change in the Arctic by integrating its geophysical and biological
expertise. Foremost among USGS biological studies in the Arctic is a
long-term program of polar bear research. Owing to both the study's
three-decade history and its longstanding collaboration with countries
within the circumpolar distribution of polar bears, the USGS has
accumulated a robust baseline of data crucial for assessment of
population status in long-lived species such as the polar bear, for
defining essential habitats, and for making projections of population
status into the future. Nine recently released USGS reports build on
this history of research and culminate in a new rangewide forecast of
polar bear status under various projections of future climate change
(Amstrup et al., 2007; Bergen et al., 2007; DeWeaver, 2007; Durner et
al., 2007; Hunter et al., 2007; Obbard et al., 2007; Regehr et al.,
2007a; Rode et al., 2007; Stirling et al., 2007).
Polar bears occur throughout portions of the Northern Hemisphere
where the sea is ice-covered for all or much of the year and
essentially derive their sustenance predominantly from ice seals such
as ringed seals. The dependence of polar bears on hunting at the ice
surface raises concern about the implications of sea ice loss. In the
southern parts of the polar bear range, such as Hudson Bay, the sea ice
melts entirely each summer and bears fast until the ice refreezes in
autumn. However, warming temperatures have established a trend of
earlier sea ice break-up, leaving the bears stranded on land and
deprived of food for longer periods of time (Stirling and Parkinson,
2006). Recent data published by USGS and Canadian scientists document
lower survival rates among young and sub-adult bears and establish
scientific linkages between less ice cover, reduced survival, and
population decline (Regehr et al., 2007b).
Similar to the early-warning signs seen in Western Hudson Bay,
declines in body condition and survival are now documented for polar
bears in Southern Hudson Bay and the Southern Beaufort Sea. These and
other signs of stressed polar bear populations, together with the
observed and forecasted declines in sea ice, prompted the USGS to
assemble a team of polar bear, sea ice, and modeling experts aimed at
reducing the uncertainties of observed and forecasted polar bear
population status worldwide.
Because of the poor fossil record, we do not know how the
forecasted distribution of bears compares to bear distribution at other
times in the past when ice extent may have been restricted similarly to
the models used for our forecasting.
The USGS assessed the pattern of observed changes in polar bear-sea
ice habitat over the last two decades and forecasted the range of
likely future habitat conditions out to the end of the century. Using
long-term satellite tracking data from polar bear populations
inhabiting the polar basin (Arctic Ocean), the USGS constructed habitat
selection models using data collected during 1985-1995, before the sea
ice changes had become pronounced. The resulting models demonstrated a
strong preference for sea ice habitats that were near the periphery of
the ice pack and over the shallow waters of the continental shelf. USGS
habitat models for the 1996-2006 period found preferred habitats have
already declined, especially in spring and summer with greatest losses
in the Southern Beaufort, Chukchi, Barents, and Greenland seas (Durner
et al., 2007).
The USGS then projected the range of likely future polar bear
habitat conditions employing ten General Circulation Models (GCM) from
the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment
Report. These models were selected on the basis of their ability to
reasonably simulate the amount of observed sea ice cover in the
Northern Hemisphere during the 20th century. It should be noted that
the USGS used GCM projections derived entirely from the IPCC SRES-A1B
greenhouse gas emissions scenario, which is also called the ``business
as usual'' or ``middle of the road'' scenario, to develop sea ice
projections. Preliminary USGS analyses of other emission scenarios (as
corroborated in the IPCC Fourth Assessment Report) indicate that
scenarios with less atmospheric carbon dioxide loading do not make a
substantive change in polar bear outcomes through mid-century, but do
result in less depletion of sea ice and thus polar bear habitat at the
end of the century.
Projections from the 21st century-based models exacerbated the
already observed habitat losses, and added losses throughout all
regions bordering Russia. Annual habitat loss for the full basin is
projected at more than 35 percent by the end of the century, with a
summer loss of nearly 80 percent for the Alaska-Eurasia portions of the
Basin. In contrast, polar bear habitats were projected to be relatively
stable during the 21st century in the high-latitude regions along the
northwestern Canadian Archipelago and northern Greenland. These results
are consistent with the general observation that most GCMs project
modest ice declines in winter but strong declines in summer, resulting
in either ice-free summers or remnant summer ice at the northernmost
latitudes of North America.
To forecast the status of polar bear populations worldwide during
the 21st century requires not only information on likely future habitat
condition (Durner et al., 2007) but also projections of population
status based on present vital rates (Hunter et al., 2007). The USGS
then developed a Bayesian network (BN) model structured around
population stressors that could affect the factors considered in
Endangered Species Act decisions (Amstrup et al., 2007). The BN model
combined empirical data, interpretations of data, and professional
knowledge into a probabilistic framework. The BN model incorporated
information about annual and seasonal sea ice trends on populations as
well as potential effects of other population stressors such as
harvest, disease, predation, and effects of increasing human activity
in the north due to ice retreat. Sensitivity analyses of the final
model indicates that sea ice habitat loss is the overarching stressor
responsible for model outcomes. Model results show that by mid-century,
polar bear populations will likely be extirpated, or eliminated, from
their southernmost range in southeastern Canada, as well as from
regions of the polar basin bordering Alaska, Russia, and Europe. By
late-century, populations in East Greenland and the Northern Beaufort
Sea also have a high probability of extirpation. Model projections
indicate a high likelihood of extirpation from regions of the Arctic
that presently support two-thirds of the worldwide population of polar
bears. These models, however, also predict a strong likelihood of
remnant populations surviving in the high Arctic, which may provide a
source of animals to reestablish former ranges if the Arctic's sea ice
environment were to be restored by an ultimate slowing and reversal of
global warming.
The USGS recognizes that the momentum of atmospheric greenhouse gas
loading will challenge us with climate-related issues for at least the
next 30-50 years. As such, we anticipate that the traditional
approaches to natural resource conservation, public land management,
and civil infrastructure planning may require accommodating and
adapting to ecosystem change. The USGS conducts scientific research to
understand the likely consequences of climate change, especially by
studying how climate has changed in the past, then using the past to
forecast responses to shifting climate conditions in the future,
distinguishing between natural and human-influenced changes, and
recognizing ecological and physical responses to changes in climate.
These strengths allow the USGS to play a critical role in conducting
climate change science across the Nation. A better understanding of sea
ice must be combined with an understanding of ecological responses and
adaptation. We believe that coupled physical-biological forecasting
approaches, as presented in recent USGS polar bear reports, will better
prepare decision-makers as they address climate adaptation. Such
forecasting will require continued long-term monitoring, focused
studies of process, and the application of new and emerging modeling
approaches implemented through collaborative efforts among federal,
academic and other partners.
Thank you for the opportunity to present this testimony. I am
pleased to answer any questions you and other Members of the Committee
might have.
References:
Amstrup, S.C., B. Marcot, and D.C. Douglas. 2007. Forecasting the
range-wide status of polar bears at selected times in the 21st
century. USGS Report to USFWS.
Belchansky, G.I., D.C. Douglas, and N.G. Platonov. 2004. Duration of
the Arctic sea ice melt season: regional and inter-annual
variability, 1979-2001. J. Climate, 17:67-80.
Belchansky, G.I., D.C. Douglas, and N.G. Platonov. 2005. Spatial and
temporal variations in the age structure of Arctic sea ice.
Geophys. Res. Lett., 32, L18504, doi:10.1029/2005GL023976.
Bergen, S., G.M. Durner, D.C. Douglas, and S.C. Amstrup. 2007.
Predicting movements of female polar bears between summer sea
ice foraging habitats and terrestrial denning habitats of
Alaska in the 21st century: Proposed methodology and pilot
assessment. USGS Report to USFWS.
DeWeaver, E. 2007. Uncertainty in climate model projections of arctic
sea ice decline. USGS Report to USFWS.
Durner, G.M., D.C. Douglas, R.M. Nielson, S.C. Amstrup, and T.L.
McDonald. 2007. Predicting the future distribution of polar
bears in the pelagic Arctic from resource selection functions
applied to 21st century general circulation model projections
of sea ice. USGS Report to USFWS.
Hunter, C.M., H. Caswell, M.C. Runge, E.V. Regehr, S.C. Amstrup, and I.
Stirling. 2007. Polar bear demography in the Southern Beaufort
Sea in relation to sea ice. USGS Report to USFWS.
Lindsay, R.W., and J. Zhang. 2005. The thinning of arctic sea ice,
1988-2003: Have we passed a tipping point? J. Climate, 18:4879-
4894.
Maslanik, J.A., S. Drobot, C. Fowler, W. Emery, and R. Barry. 2007. On
the Arctic climate paradox and the continuing role of
atmospheric circulation in affecting sea ice conditions.
Geophys. Res. Lett., 34, L03711, doi:10.1029/2006GL028269.
Obbard, T.L. McDonald, E.J. Howe, E.V. Regehr, and E.S. Richardson.
2007. Polar Bear Population Status in Southern Hudson Bay,
Canada. USGS Report to USFWS.
Polyakov, I., and 19 others. 2007. Observational program tracks Arctic
Ocean transition to a warmer state. Eos., 88(40):398-399.
Regehr, E.V., C.M. Hunter, H. Caswell, S.C. Amstrup, and I. Stirling.
2007a. Survival and reproduction of polar bears in the Southern
Beaufort Sea in relation to declining sea ice. USGS Report to
USFWS.
Regehr, E.V., N.J. Lunn, I. Stirling, and S.C. Amstrup. 2007b in press.
Effects of earlier sea ice breakup on survival and population
size of polar bears in Western Hudson Bay. Journal of Wildlife
Management. 71(8):000-000.
Rigor, I.G., and J.M. Wallace. 2004. Variation in the age of Arctic
sea-ice and summer sea-ice extent. Geophys. Res. Lett., 31,
L09401, doi:10.1029/2004GL019492.
Rode, K.D., S.C. Amstrup, and E.V. Regehr. 2007. Polar bears in the
Southern Beaufort Sea: Body size, mass, and cub recruitment in
relationship to time and sea ice extent between 1982 and 2007.
USGS Report to USFWS.
Serreze, M. and J. Francis. 2006. The Arctic on the fast track of
change. Weather. 61(3):65-69.
Stirling, I., T. McDonald, E. Richardson, and E. Regehr. 2007. Polar
bear population status in the Northern Beaufort Sea.. USGS
Report to USFWS.
Stirling, I. and C. Parkinson. 2006. Possible effects of climate
warming on selected populations of polar bears (Ursus
maritimus) in the Canadian Arctic. Arctic, 59 (3):261-275.
Stroeve, J., T. Markus, W. Meier, and J. Miller. 2006. Recent changes
in the Arctic melt meason. Ann. Glaciol., 44(1):367-374
Woodgate, R.A., K. Aagaard, and T.J. Weingartner. 2006. Interannual
changes in the Bering Strait fluxes of volume, heat and
freshwater between 1991 and 2004. Geophys. Res. Lett., 33,
L15609, doi:10.1029/2006GL026931.
Biography for Susan D. Haseltine
Career History and Highlights:
Dr. Haseltine has been with the USGS for more than 10 years. Before
joining the USGS, she was Eastern Region Director for the former
National Biological Service (NBS), and she became Chief Scientist for
Biology when the NBS joined the USGS in 1996.
Prior to joining the NBS, she managed the Refuges and Wildlife
program in the Upper Midwest in Minneapolis, Minn., for the U.S. Fish
and Wildlife Service (FWS) after serving as the Center Director for the
Northern Prairie Wildlife Research Center in Jamestown, N. Dak. She
joined the FWS as a researcher for the Patuxent Wildlife Research
Center in Laurel, Md., and worked for more than a decade as a
researcher and research manager before moving onto the Northern Prairie
Wildlife Research Center.
Education:
Dr. Haseltine has a doctorate and Master's in zoology from Ohio
State University and a Bachelor's in wildlife science from the
University of Maine.
Chairman Miller. Thank you, Dr. Haseltine. My great fear is
that Mr. Rohrabacher is going to think that my indulgence that
I am showing today on time limits for witnesses' testimony will
also apply for time limits for Members' questioning.
Ms. Siegel.
STATEMENT OF MS. KASSIE R. SIEGEL, DIRECTOR, CLIMATE, AIR AND
ENERGY PROGRAM, CENTER FOR BIOLOGICAL DIVERSITY, JOSHUA TREE,
CALIFORNIA
Ms. Siegel. Good morning, Mr. Chairman, and Members of the
Committee. Thank you so much for the opportunity to testify.
Early next year the polar bear will likely be listed as
threatened or endangered under the Endangered Species Act.
While enormously significant both legally and politically, the
listing of the polar bear will not in and of itself be enough
to save the polar bear or its Arctic Sea ice habitat. Last
month the Arctic Sea ice reached a stunning new minimum.
The sea ice looked like this in September 1979, and like
this in September 2007. This is a loss of one million square
miles off the average minimum sea ice extent of the past
several centuries, and the melt is happening faster than
forecast. This slide shows climate model predictions of sea ice
extent and the dashed colored lines compared to actual observed
sea ice extent in the heavy red line.
Sea ice in September 2007 was far below what any of the
models predicted and perhaps most worrisome, there is less ice
in the Arctic this year than more than half the models project
for 2050.
The polar bear is a creature of the sea ice and needs the
ice for all of its essential behaviors, including traveling and
mating and hunting the primary prey of ice-dependent seals.
Polar bears cannot hunt seals from land, and so tied to the ice
are they that some mother polar bears even give birth to their
cubs in snow dens like this one on top of the drifting ice.
Polar bears cannot survive without their Arctic sea ice
habitat. The situation for polar bears in a rapidly warming
Arctic is grim. Polar bears are drowning, resorting to
cannibalism when they don't have access to their usual food
sources, and starving.
This photograph was taken in Quebec, Canada, last month.
This bear is in the final stages of starvation. While we cannot
say for sure that this bear died as a direct result of global
warming, we do know that global warming is increasing and will
continue to increase the number of bears that suffer this fate.
But we also know that it is not too late to do something about
it. Motivated by the need to do so, the Center for Biological
Diversity filed a petition to list the polar bear under the
Endangered Species Act in February 2005. The listing process
has already benefited the species by raising awareness of its
plight and leading to new information, such as the U.S. study
which predicts the extinction of two-thirds of the world's
polar bears by 2050 which was conducted in support of the
listing process.
The Arctic has reached a critical threshold, and our window
to act, like the ice itself, is melting rapidly away; but it is
not too late. The grim projections from the USGS are based on
the A1B IPCC Emission Scenario in which CO2
concentrations reached 717 parts per million by the end of this
century. We know that business as usual cannot continue, and we
must limit CO2 concentrations to below 450 parts per
million. We need deep, rapid, and mandatory reductions in
CO2 to save the polar bear. But the Arctic has
advanced so far toward the tipping point that CO2
reductions are now necessary but not sufficient to save polar
bears. Anything else we do may be futile if we don't address
this most important of greenhouse gases. CO2 has a
long atmospheric lifetime, so the benefits of CO2
reductions today will take a long time to be fully felt. We
need a way to buy ourselves some time. Fortunately, we have an
opportunity to do just that by addressing methane and black
carbon emissions, both pollutants with short atmospheric
lifetimes and a very high warming impact in the Arctic. By
attacking methane and black carbon emissions, we can have a
short-term benefit in the Arctic, and we can provide ourselves
with the last and golden opportunity to give polar bears back
their future.
Methane is a globally well-mixed gas, 21 times more
powerful than CO2 but stays in the atmosphere for
about 12 years. Methane also leads to higher levels of
tropospheric ozone, which has a high warming impact in the
Arctic where it absorbs light energy reflected off the snow and
ice. So by reducing methane we can also reduce ozone levels in
the Arctic and provide a double benefit to the region in the
short-term.
Further good news is that there are enormous amounts of
cost-positive and no-cost methane reductions sitting on the
table today. We have fantastic opportunities to capture methane
from landfills and from livestock operations and use it to
generate energy and to reduce methane losses from natural gas
systems, just to name a few. According to conservative
projections from the U.S. EPA, conservative estimates, we can
reduce nearly 70 million metric tons of CO2
equivalent methane emissions in the U.S. by 2010 at a cost
benefit or no cost. That is the equivalent of getting paid to
take 12 million cars off the road, and we can do so much more
at low cost. But voluntary measures and the market have not
provided the so-called no regrets emission reductions. We
desperately need Congressional action.
Black carbon or soot is emitted from the inefficient
burning of fossil fuels, biofuels, and biomass. We have
opportunities to reduce soot from sources such as diesel fuel
and coal-fired power plants. Soot remains in the atmosphere for
only about five days but has an extraordinarily powerful
warming impact of about 500 times that of CO2 over a
100-year period. It is particularly important to address within
Arctic sources like diesel generators and ship engines.
The rapid melting of the Arctic is the Earth's early
warning system, and yet like beachgoers chasing the receding
waters immediately prior to a tsunami to gather up the exposed
shellfish, nations and industry are racing to the newly ice-
free areas to stake claims for fossil fuel development and
shipping routes that would commit us further down the path to
climate catastrophe.
To save the polar bear, we must not only find courage to
reduce greenhouse gas pollution but also to protect the Arctic
from further industrial exploitation. We believe that Congress
should act immediately to slash methane and black carbon
emissions. Methane emissions from landfills, livestock
operations, natural gas systems, and other sources should be
strictly limited. Black carbon emissions from the use of diesel
fuel and coal must also be addressed. These measures will also
greatly benefit our economy and public health. We also believe
Congress should enact a moratorium on new fossil fuel leasing
and development in the Arctic where these activities both
directly impact the species most at risk for global warming and
also contribute substantially to greenhouse gas emissions.
If we truly act with speed and determination, it is not too
late to save the polar bear, to save the entire productive
Arctic ecosystem, and to avoid the worst impacts of global
warming for ourselves.
Thank you.
[The prepared statement of Ms. Siegel follows:]
Prepared Statement of Kassie R. Siegel
Not too Late to Save the Polar Bear: A Rapid Action Plan to Address the
Arctic Meltdown
In early 2008, the polar bear will likely be formally declared
``threatened'' or ``endangered'' under the Endangered Species Act. But
listing of the polar bear under the Endangered Species Act, while
hugely significant both legally and politically, will not in and of
itself save the polar bear or its Arctic sea-ice habitat. In September
2007, the same month that Arctic sea ice reached a new record minimum
extent, government scientists predicted the polar bear would be extinct
in Alaska by 2050 if current greenhouse gas emission trends continue.
Predictions of polar bear extinction by 2050 may be optimistic.
Recent reports from scientists indicate that global warming impacts are
occurring earlier and more intensely than previously projected. Nowhere
is this more apparent than in the Arctic where, in 2007, sea-ice extent
shrank to a record one million square miles below the average summer
sea-ice extent of the past several decades, reaching levels not
predicted to occur until mid-century. Not only does the impending loss
of Arctic sea ice mean the loss of an entire ecosystem, it will also
greatly amplify warming impacts on a global level due to the greater
absorption of the sun's energy by open water compared to the reflective
ice.
The rapid melting of the Arctic should be seen as an early warning
of the broader climate crises to come if the U.S. and the world do not
respond to global warming with the necessary urgency. Instead, like
beach-goers chasing the receding waters immediately prior to a tsunami
to gather up the exposed shellfish, nations and industry are racing to
the newly ice-free areas to stake claims for fossil fuels and shipping
routes that would lead us further down the path to climate catastrophe.
The situation in the Arctic has reached a critical threshold. But
with immediate action it is still possible to slow the melting of the
Arctic. In addition to broader local, national, and international
efforts to reduce U.S. and global carbon dioxide (CO2)
emissions, saving the Arctic requires prompt reductions of other
greenhouse gases, along with specific efforts to address direct threats
to the region from industrial activities such as oil development and
shipping. Reducing emissions of methane and black carbon, which both
have short atmospheric lifetimes and a large warming impact on the
Arctic, is a critical component of any effective action plan. Immediate
methane and black carbon emissions reductions can buy the world a
little more time to achieve the deep reductions in CO2
emissions that are necessary to protect the far north. But the window
of opportunity to act, like the ice, is shrinking rapidly.
I. The Polar Bear, Global Warming, and the Endangered Species Act
Polar bears are completely dependent upon Arctic sea-ice habitat
for survival. Polar bears need sea ice as a platform from which to hunt
ringed seals and other prey, to make seasonal migrations between the
sea ice and their terrestrial denning areas, and for other essential
behaviors such as mating. Unfortunately, the polar bear's sea-ice
habitat is literally melting away.
Global warming is impacting the Arctic earlier and more intensely
than any other area of the planet. In parts of Alaska and western
Canada, winter temperatures have increased by as much as
3.5+C in the past 30 years (Rozenzweig et al., 2007). Over
the next 100 years, under a moderate emissions scenario, annual average
temperatures in the Arctic are projected to rise an additional 3-
5+C over land and up to 7+C over the oceans
(Meehl et al., 2007).
This rapid observed and projected warming is reflected in the
devastating melt of the Arctic sea ice, which is highly sensitive to
temperature changes. Summer sea-ice extent reached an unpredicted and
utterly stunning new record minimum in 2007 (NSIDC, 2007a,b; Figures 1,
2). At 1.63 million square miles, the minimum sea-ice extent on
September 16, 2007 was about one million square miles\1\ below the
average minimum sea ice extent between 1979 and 2000 (NSIDC, 2007a).
The 2007 minimum was lower than the sea-ice extent most climate models
predict would not be reached until 2050 or later. Leading sea ice
researchers now believe that the Arctic could be completely ice free in
the summer as early as 2030 (NSIDC, 2007b).
---------------------------------------------------------------------------
\1\ One million square miles is equal to about the area of Alaska
and Texas combined.
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Climate change in the Arctic has reached a critical threshold, and
the future of the ice-dependent polar bear is grim. Even short of
complete disappearance of sea ice, projected impacts to polar bears
from global warming will affect virtually every aspect of the species'
existence. These impacts include a reduction in the hunting season
caused by delayed ice formation and earlier break-up, resulting in
reduced fat stores, reduced body condition, and subsequent reduced
survival and reproduction; increased distances between the ice edge and
land, making it more difficult for bears to reach preferred denning
areas; increased energetic costs of traveling farther between ice and
land and through fragmented sea ice; and reduction in ice-dependent
prey such as ringed seals and bearded seals (Derocher et al., 2004).
Global warming will also increase the frequency of human/bear
interactions, as greater portions of the Arctic become more accessible
to people and as polar bears are forced to spend more time on land
waiting for ice formation (Derocher et al., 2004). More human/bear
interactions will almost certainly lead to increased polar bear
mortality.
Five of the world's polar bear populations are now classified as
declining, with a 22 percent decline--from 1,194 bears in 1987 to 935
bears in 2004--in Canada's Western Hudson Bay polar bear population
(Aars et al., 2006). Recently, reports of polar bear drownings,
cannibalism, and starvation have increased (Amstrup et al., 2006;
Regehr et al., 2006; Aars et al., 2006). With the amount, location, and
access to their ice-dependent seal prey changing rapidly, polar bears
are increasingly vulnerable to starvation.
Figure 1 shows a polar bear in the final stages of starvation. This
photo was taken on September 4, 2007 on the Caniapiscau River in
Canada, 160 km inland from Ungava Bay. While we cannot say for sure
that this bear starved to death as a direct result of global warming,
as we do not know the bear's history or origin, we do know that global
warming will increase the number of bears that suffer this fate. We
also know that we have the power to limit the number of polar bears
that starve, drown, and resort to cannibalism, and to save the species
from extinction by immediately reducing greenhouse gas pollution.
The Center for Biological Diversity submitted a Petition to the
Secretary of the Interior and U.S. Fish and Wildlife Service to list
the polar bear under the Endangered Species Act due to global warming
on February 16, 2005, motivated by the urgent need to reduce greenhouse
gas pollution and otherwise protect the species. The Endangered Species
Act is our nation's safety net for plants and animals on the brink of
extinction, and our strongest and best law for the protection of
imperiled wildlife. The Endangered Species Act listing process has
already benefited the polar bear, will provide additional protections
once the species is formally listed, and is a key component of saving
the species.
Critically important for the polar bear and any other species
threatened by global warming, the Endangered Species Act requires all
listing decisions be made ``solely'' on the basis of the ``best
scientific. . .data available.'' 16 U.S.C. 1533(b)(1)(A). A decision
not to list a petitioned species is subject to judicial review. It is
this ``best available science'' standard that provides a vehicle
through the petitioning process to force federal agencies to squarely
address the science of global warming. Moreover, once the Endangered
Species Act listing process is initiated, strict timelines apply, with
an initial finding due within 90 days of the petition, a proposed rule
within 12 months of the petition if the Fish and Wildlife Service finds
that the species meets the criteria for listing, and a final listing
determination within a year from the proposed rule. Species do not
receive any regulatory protection under the Act until they are
officially listed as threatened or endangered.
A series of administrative and legal events in the listing process
have greatly increased public awareness of the polar bear's plight. In
December 2005, ten months after the Petition was filed, the Center for
Biological Diversity, joined by NRDC and Greenpeace, sued the
Department of Interior for failing to issue an initial finding on the
Petition. In response, a positive initial finding was issued in
February, 2006, initiating both a public comment period and full status
review for the species. The deadline for the second required finding on
the Petition, due within 12 months of receipt of the petition, was only
one week away at the time the first finding was made. The lawsuit was
ultimately settled with a court-ordered consent decree setting a
deadline of December 27, 2006 for the Fish and Wildlife Service to make
the second determination.
On December 27, 2006, Secretary of Interior Dirk Kempthorne
announced that listing of the polar bear is warranted and that the Fish
and Wildlife Service would be publishing a proposed listing rule. The
proposal to list the polar bear was greeted by worldwide media
attention, resulting in over 250 television stories, more than 1000
print stories and over 240 editorials. Over 600,000 comments were
submitted during the public comment periods on the proposal. The final
listing determination is due on January 9, 2008.
Once the polar bear is listed, the Endangered Species Act requires
the Fish and Wildlife Service to identify and designate critical
habitat, convene a recovery team and develop and implement a recovery
plan. Additionally, the requirement for federal agencies to avoid
jeopardizing the species, and a prohibition against unpermitted take
(harm and harassment), will take effect. These regulatory protections
should provide substantial benefit to the polar bear (Cummings and
Siegel, 2007). While the polar bear has yet to receive any actual legal
protection as a result of the Endangered Species Act listing process,
the process has already played an important role by being a catalyst to
focus significant new scientific, public, and political attention on
the problem of the melting Arctic and global warming.
The listing process has prompted research and analysis on the
future of the polar bear, its sea-ice habitat, and the Arctic more
generally. Most important among these research efforts are the recent
reports released by the Department of Interior's U.S. Geological Survey
(USGS). The Fish and Wildlife Service asked the USGS to do the
following in support of the listing process: (1) develop population
projections for the Southern Beaufort Sea polar bear population and
analyze existing data on two polar bear populations in Canada; (2)
evaluate northern hemisphere sea-ice projections, as they relate to
polar bear sea-ice habitats and potential future distribution of polar
bears; and (3) model future range-wide polar bear populations by
developing a synthesis of the range of likely numerical and spatial
responses to sea-ice projections. The USGS produced nine administrative
reports addressing these questions and in doing so significantly
advanced the understanding of sea-ice loss and its implications for
polar bears.
The USGS conducted polar bear population modeling based on 10
climate models that most accurately simulate future ice conditions. The
USGS used the Intergovernmental Panel on Climate Change (``IPCC'') A1B
``business as usual'' scenario of future emissions to run the climate
models. In the A1B scenario, atmospheric carbon dioxide concentrations
reach 717 parts per million by 2100. These sea-ice projections were
used in a number of applications, including in a Bayesian Network model
developed by the USGS to most accurately project the future range-wide
status of the polar bear. The results are disturbing.
The USGS (Amstrup et al., 2007) project that two-thirds of the
world's polar bears will be extinct by 2050, including all of the bears
in Alaska. The ``good news'' is that polar bears may survive in the
high Canadian Archipelago and portions of Northwest Greenland through
the end of this century. However, their extinction risk is still
extremely high: over 40 percent in the Archipelago and over 70 percent
in Northwest Greenland (Amstrup et al., 2007:Table 8).
Moreover, the USGS emphasizes repeatedly that because all of the
available climate models have to date underestimated the actual
observed sea-ice loss, the assessment of risk to the polar bear may be
conservative. Perhaps most worrisome is the observation that part of an
area in the Canadian Archipelago expected to provide an icy refuge for
the polar bear in 2100 lost its ice in the summer of 2007.
The USGS projections of polar bear extinction risk are based on the
IPCC A1B ``business as usual'' scenario, near the center of the
distribution of all IPCC scenarios, in which atmospheric carbon dioxide
concentrations reach 717 parts per million by 2100 (Nakicenovic, 2000).
If future emissions meet or exceed the A1B scenario, the eventual
extinction of polar bears is virtually guaranteed, as extinction risk
will exceed 40 percent even in the high Canadian Archipelago in 2100,
and warming will continue after 2100. The USGS reports, however, do not
address the question of how much polar bear extinction risk can be
reduced if greenhouse gas emissions are curtailed significantly below
those assumed in the A1B scenario. Decreasing greenhouse gas emissions
substantially can limit the Arctic sea-ice melt and therefore lower
extinction risk for the polar bear.
While not explicitly making an Endangered Species Act listing
recommendation, the information contained in the USGS reports
definitively answers the question of whether the polar bear is in fact
in danger of extinction and therefore warrants the protections of the
Act with an emphatic and distressing ``yes.'' Any decision by the Fish
and Wildlife Service to deny or delay listing would be patently
unlawful. The point of the Endangered Species Act, however, is not
simply to add species to the list, but to actually save them. If
``business as usual'' emissions trends continue, the polar bear will be
driven extinct irrespective of Endangered Species Act listing or any
other management actions. Business as usual is simply no longer an
option. If the polar bear is to have a future, we as a nation and as a
global community must immediately begin implementing deep greenhouse
gas emissions reductions as well as change our management paradigms to
reflect the new realities presented by a warming Arctic. The remainder
of this paper sets forth an action plan to do so.
II. Reducing Greenhouse Pollutants Rapidly Enough to Address Arctic
Melting
The essential first component of an action plan to save the polar
bear is a mandatory reduction in CO2 pollution. Beginning
CO2 reductions immediately and eventually reducing them to a
small fraction of current levels such that atmospheric CO2
concentrations never rise above about 450 ppm is essential to saving
polar bears. But the Arctic has reached such a critical threshold that
CO2 reductions alone, even if undertaken immediately and
with determination, will almost certainly not be enough to slow and
reverse the warming and melting trend. This is because CO2,
once emitted, tends to remain in the atmosphere for centuries (Archer,
2005), and therefore the benefits of reductions today will not be fully
felt for some time.
Our window of opportunity to save polar bears relates to the fact
that the warming impact of ``non-CO2'' pollutants including
methane, tropospheric ozone, and black carbon (soot) is larger in the
Arctic than it is globally. The non-CO2 pollutants are
responsible for at least half of the warming in the Arctic (Hansen et
al., 2007), as opposed to about 30 percent globally (Forster and
Ramaswamy, 2007; Figure 4). Black carbon has a disproportionately large
warming impact in the Arctic, and both black carbon and methane have
much shorter atmospheric lifetimes than CO2. This means that
immediately reducing these pollutants can buy some desperately needed
time and presents our best opportunity for slowing and reversing the
Arctic melting before it is too late.\2\
---------------------------------------------------------------------------
\2\ For ease of comparison, the volume of each pollutant is
expressed as its ``carbon dioxide equivalent'' in millions of metric
tons. Thus, one million metric tons of methane is equivalent to 21
million metric tons of CO2 equivalent (MtCO2eq).
---------------------------------------------------------------------------
Fortunately, there are many feasible reduction measures available
today for these pollutants, with literally hundreds of millions of
metric tons of CO2eq ``no-cost'' reductions on the table,
including many that could be undertaken at a net economic benefit.
(Tables 1-4). According to conservative projections by the U.S. EPA,
about 500 MtCO2eq of global methane emissions reductions
could be achieved globally by 2020 at a cost benefit or no cost (EPA,
2006; Table 4, Figure 7). Nearly 70 MtCO2eq of these
available reductions are in the United States (EPA, 2006; Table 2,
Figure 6). The EPA estimates total technically feasible methane
reductions for 2020 at over 2400 MtCO2eq globally and nearly
280 MtCO2eq in the U.S., many of which can be achieved at
low cost (EPA, 2006; Tables 2 and 4; Figures 6,7).
Reductions in CO2, methane and black carbon will have
major public health benefits as well. Many of the measures necessary to
reduce global warming pollution, including increasing energy
efficiency, increasing the use of renewable energy and phasing out
fossil fuels, and ultimately changing our land use, transportation, and
consumption patterns, will improve our quality of life, improve our
economy, and make the world a healthier, safer, and more equitable
place. Congress should act immediately to explicitly cap and then
rapidly reduce not only CO2, but also the non-CO2
pollutants.
Below we review necessary reductions in greenhouse gas pollutants
and opportunities for targeted actions to protect the Arctic. Further
detail on mitigation strategies for methane, black carbon, nitrous
oxide, and the high global warming potential gases is found in Appendix
A.
A. Carbon Dioxide
Because CO2 is the most important greenhouse gas, the
rapid and mandatory reduction of CO2 emissions is the
backbone of any plan to slow the Arctic melt (Quinn et al., 2007) and
thus save the polar bear. If carbon dioxide concentrations are not
controlled soon, polar bears will have little chance of future survival
regardless of what else is done. Leading scientists warn that CO2
concentrations must be kept below about 450 ppm in order to keep the
climate system within the range of variability of the past 650,000
years and minimize the chance of triggering major climate feedbacks,
such as a large scale release of methane from the Arctic permafrost,
that would greatly amplify anthropogenic warming (Hansen et al., 2006;
Hansen et al., 2007). They further warn that the 450 ppm limit may need
to be reduced further in the future (Hansen and Sato, in prep.).
Keeping global CO2 concentrations below 450 parts per
million would require the U.S. to begin reducing its emissions quickly,
and to reduce them to 80 percent or more below 1990 levels by the
middle of this century.
It is essential that the U.S. rejoin the U.N. Framework Convention
on Climate Change negotiating process and participate in global
solutions. The Bush Administration has been blocking progress at the
international level for over six years, and the U.S. and Australia are
the only developed countries that have refused to ratify the Kyoto
Protocol, the first mandatory greenhouse gas reduction agreement under
the Framework Convention process. The U.S. should commit to meeting its
Kyoto target of reducing its emissions to seven percent below 1990
levels between 2008 and 2012, and join negotiations for much deeper
emissions reductions after 2012.
Congress must pass legislation that caps and rapidly reduces
greenhouse gas pollution with mandatory measures. Fortunately, there
are several bills introduced that if passed, enacted, and fully
enforced, would result in emissions dropping to approximately 80
percent below 1990 levels by 2050, including the Safe Climate Act (H.R.
1590, Waxman) and the Global Warming Pollution Reduction Act (S. 309,
Sanders). The survival of the Arctic sea ice and the polar bear depends
upon one of these bills or something similar becoming law soon.
However, the Arctic melt has advanced so far towards a tipping
point that CO2 reductions are necessary, but not sufficient,
to save polar bears. In addition to current legislative proposals,
Congress must target other pollutants, including methane and black
carbon, to provide the necessary short-term climate benefit to the
Arctic.
B. Methane
Methane is the most important of the non-CO2 pollutants,
with a global warming potential 21 times greater than carbon dioxide,
and an atmospheric lifetime of 12 years (Forster and Ramaswamy, 2007).
Methane constitutes approximately 20 percent of the anthropogenic
greenhouse effect globally, the largest contribution of the non-
CO2 gases. As a precursor to tropospheric ozone, methane
emissions have an even more powerful impact on climate. In the Arctic
this impact is strongest in winter months, which can result in an
acceleration of the onset of spring melt (Shindell, 2007). Tropospheric
ozone, unlike other greenhouse gases, absorbs both infrared radiation
and shortwave radiation (visible light). Thus, tropospheric ozone is a
particularly powerful greenhouse gas over highly reflective surfaces
like the Arctic, because it traps shortwave radiation both as it enters
the Earth's atmosphere from the sun and when it is reflected back out
again by snow and ice. Reducing global methane emissions will reduce
ozone concentrations in the Arctic, providing a double benefit to the
region.
According to conservative projections by the U.S. EPA, about 500
MtCO2eq of methane emissions reductions could be achieved
globally by 2020 at a cost benefit or at no cost (EPA, 2006; Table 4,
Figure 7). That is the equivalent of taking almost 90 million cars and
light trucks off the road. Nearly 70 MtCO2eq of these
available reductions are in the United States (EPA, 2006; Table 2,
Figure 6). That is the equivalent of taking over 12 million cars and
light trucks off the road. The EPA estimates total technically feasible
methane reductions for 2020 at over 2400 MtCO2eq globally
and nearly 280 MtCO2eq in the U.S., many of which can be
achieved at low cost (EPA, 2006; Tables 2 and 4; Figures 6, 7).
The EPA's cost projections are conservative for a number of
reasons, including the use of a 10 percent discount rate. Using a lower
discount rate would result in additional cost benefit or no-cost
reductions. Moreover, the EPA analysis does not account for the value
of significant air quality and health benefits that would accompany
methane reductions. West et al. (2006) found that reducing global
methane emissions by 20 percent would save 370,000 lives between 2010
and 2030, due to the reduction in ozone related cardiovascular,
respiratory, and other health impacts. Methane reductions would also
decrease ozone-related damage to ecosystems and agricultural crops
(West et al., 2006). Methane is the primary component of natural gas,
and many abatement options include the use of captured methane to
generate energy. The benefits of displacing other fossil fuel energy
sources with captured methane are also not captured in the EPA (2006)
analysis.
While EPA (2006) may underestimate available no-cost and low-cost
methane (and other non-CO2 gas) mitigation options, even
this conservative analysis shows the enormous opportunities available
to us today (Tables 1-4; Figures 6-7). These reductions can be achieved
with currently available technology, as described in Appendix A.
Moreover, mandatory greenhouse gas regulation will speed the
development and deployment of new technology and mitigation options,
making much deeper reductions feasible in the very near future.
C. Black Carbon or Soot
Black carbon, or soot, consists of particles or aerosols released
through the inefficient burning of fossil fuels, biofuels, and biomass
(Quinn et al., 2007). Black carbon warms the atmosphere, but it is a
solid, not a gas. Unlike greenhouse gases, which warm the atmosphere by
absorbing long-wave infra-red radiation, soot has a warming impact
because it absorbs short-wave radiation, or visible light (Chameides
and Bergin, 2002). Black carbon is an extremely powerful greenhouse
pollutant. Scientists have described the average global warming
potential of black carbon as about 500 times that of carbon dioxide
over a 100 year period (Hansen et al., 2007; see also Reddy and
Boucher, 2007). This powerful warming impact is remarkable given that
black carbon remains in the atmosphere for only about four to seven
days, with a mean residence time of 5.3 days (Reddy and Boucher, 2007).
Black carbon contributes to Arctic warming through the formation of
``Arctic haze'' and through deposition on snow and ice which increases
heat absorption (Quinn et al., 2007; Reddy and Boucher, 2007). Arctic
haze results from a number of aerosols in addition to black carbon,
including sulfate and nitrate (Quinn et al., 2007). The effects of
Arctic haze may be to either increase or decrease warming, but when the
haze contains high amounts of soot, it absorbs incoming solar radiation
and leads to heating (Quinn et al., 2007).
Soot also contributes to heating when it is deposited on snow
because it reduces reflectivity of the white snow and instead tends to
absorb radiation. A recent study indicates that the direct warming
effect of black carbon on snow can be three times as strong as that due
to carbon dioxide during springtime in the Arctic (Flanner, 2007).
Black carbon emissions that occur in or near the Arctic contribute the
most to the melting of the far north (Reddy and Boucher, 2007; Quinn et
al., 2007).
Reductions in black carbon therefore provide an extremely important
opportunity to slow Arctic warming in the short-term, and mitigation
strategies should focus on within-Arctic sources and northern
hemisphere sources that are transported by air currents most
efficiently to the Arctic. Conversely, allowing black carbon emissions
to increase in the Arctic as the result of increased shipping or
industrial activity, will accelerate loss of the seasonal sea ice and
extinction of the polar bear. Black carbon reductions will also provide
air quality and human health benefits.
Despite its significance to global climate change and to the Arctic
in particular, black carbon has not been addressed by the major reports
on non-CO2 gas mitigation, nor is it addressed in current
global warming bills in the 110th Congress. Black carbon reductions are
an essential part of saving the Arctic sea ice and the polar bear, and
should be addressed by Congress in this session. Abatement
opportunities are discussed further in Appendix A.
D. Other Non-CO2 Pollutants
Nitrous oxide and the high global warming potential gases do not
have the same heightened impacts in the Arctic as methane and black
carbon. Nevertheless, because these gases have high global warming
potentials and long atmospheric lifetimes, and because there are many
readily available mitigation measures to reduce them, they present
important opportunities for reducing global warming overall and are
therefore an important part of saving the Arctic and the polar bear.
Nitrous oxide has a global warming potential 310 times that of
carbon dioxide and an atmospheric lifetime of approximately 114 years
(Forster and Ramaswamy, 2007). It constitutes the second largest
proportion of anthropogenic non-CO2 gases at seven percent.
The main sources of nitrous oxide emissions are agriculture,
wastewater, fossil fuel combustion, and industrial adipic and nitric
acid production.
High global warming potential (High-GWP) gases fall into three
broad categories: hydrofluorocarbons (HFCs), perfluorcarbons (PFCs),
and sulfur hexafluoride (SF6). Hydrofluorocarbons were
developed to replace ozone-depleting substances used in refrigeration
and air conditioning systems, solvents, aerosols, foam production, and
fire extinguishing. HFCs have global warming potentials between 140 and
11,700 times that of carbon dioxide, and their atmospheric lifetimes
range from one year to 260 years (EPA, 2006).
Perfluorocarbons are emitted during aluminum production and
semiconductor manufacture (EPA, 2006). Their global warming potential
ranges from 6,500 to 9,200 times that of carbon dioxide. In addition,
they have extremely long atmospheric lifetimes (e.g., 10,000 and 50,000
years for two common PFCs).
The highest global warming potential exists in sulfur hexafluoride
at 23,900 times that of carbon dioxide. Sulfur hexafluoride remains in
the atmosphere for 3,200 years. Sulfur hexafluoride is used: (1) for
insulation and current interruption in electrical power transmission
and distribution; (2) during semiconductor manufacture; and (3) to
protect against burning in the magnesium industry.
Further information on abatement options for these pollutants is
found in Appendix A.
E. Reduced CO2 and Non-CO2 Pollutants and the
Future Arctic
As discussed above, keeping CO2 levels below 450 ppm and
substantially reducing all non-CO2 forcings is essential if
we are to keep global temperatures from rising more than 1+C
above 2000 levels and thereby minimize the risk of triggering major
climate feedbacks which would lead to significantly elevated warming
(Hansen et al., 2006). Achieving such greenhouse gas reductions is
therefore critical if we are to not only prevent the extinction of the
polar bear, but avoid the most catastrophic impacts of global warming.
But even under such a scenario, the Arctic will still undergo
significant additional warming with the concomitant additional loss of
sea ice. Approximately 0.6+C of additional warming is
already in the pipeline due to the excess energy in the Earth's climate
system from past greenhouse gas emissions (Hansen et al., 2005; Alley
et al., 2007). Additional warming will follow rising CO2
levels even if we keep such levels below 450 ppm. As with the warming
observed to date, the Arctic will continue to warm more rapidly than
the global average. Substantial additional reduction of Arctic sea ice
over the course of this century is therefore likely unavoidable. For
the polar bear, things are going to get much worse before they begin to
get better.
As grim as the outlook for the polar bear is, it is not hopeless.
Unlike the terrestrial ice-sheets of Greenland, the melting of which
may become irreversible on human-relevant timeframes, the Arctic sea
ice, portions of which melt and reform every year, may be capable of
relatively rapid recovery following climate stabilization. Assuming
greenhouse emission targets can be met, the climate can be stabilized,
and with subsequent reductions in atmospheric CO2 levels,
the Arctic sea ice can recover to levels supporting long-term viable
populations of polar bears and other ice-dependant species. The key to
polar bear persistence then, is weathering the very bumpy ride through
the next half-century. To shepherd the polar bear through the ensuing
decades, we must reduce all other stressors on the species and its
habitat and tailor national and international management of the
sensitive Arctic ecosystem to the new reality of a rapidly changing
Arctic.
III. A New Management Paradigm for a Warming Arctic
As the September, 2007 sea-ice minimum starkly illustrates, global
warming in the Arctic is not a future problem that can be shunted off
to the next generation of decision-makers. It has arrived and is
already leaving starving and drowning polar bears, melting permafrost
and coastal erosion in its wake. While implementing the rapid
reductions in emissions of both CO2 and non-CO2
pollutants described above is essential to avoid runaway future warming
in the Arctic and elsewhere, if polar bears are to survive we also have
to adapt policy measures to the warming that has already occurred, that
is unavoidably in the pipeline, and that will inevitably come with
projected rising atmospheric CO2 levels. The Arctic of 2007
is very different than the Arctic of just a decade ago; the Arctic of
2050 will be virtually unrecognizable.
While the ongoing changes in the Arctic are now readily apparent,
for the most part, U.S. federal agencies have utterly failed to
incorporate this new reality into their decision-making affecting the
Arctic. With the possible exception of the Department of Defense (see,
e.g., ONR, 2001), federal agencies are making planning decisions and
issuing permits, authorizations and leases in and affecting the Arctic
with a near-total disregard for the rapidly changing conditions in the
region. This is leading to uninformed and unwise decision-making
negatively affecting the polar bear and the entire Arctic ecosystem.
If U.S. agencies have been slow to recognize and respond to new
conditions as the sea ice recedes, the rest of the world has been quick
to claim the spoils of a warming Arctic. Russia, Norway and Denmark
have all recently staked competing territorial claims to portions of
the oil-rich Arctic seabed while Canada has asserted sovereignty over
the increasingly ice-free Northwest Passage. Similarly, the specter of
a seasonally ice-free Arctic carries with it the likelihood of greatly
increased shipping in the region.
Many of these elements of a changing Arctic carry a double threat
to the polar bear. Increased oil and gas development in the Arctic
threatens not just to degrade important polar bear habitat, but will
also lead to further fossil fuel commitments, making emissions
reduction targets all the more difficult to reach. Increased shipping
in the Arctic carries increased risks of oil spills and further
disruptions of the polar bear's habitat, but also, perhaps more
importantly, would lead to a substantial injection of additional black
carbon directly where it would do the most damage to the Arctic
climate. Finally, territorial disputes in the Arctic will lead to an
increased military presence in the Arctic leading to disruption and
pollution from vessels and aircraft as well as increasingly frequent
polar bear/human interactions--encounters that the polar bears almost
always lose.
If we are to respond to the warming Arctic in a manner compatible
with the long-term survival of the polar bear, we must directly
confront the changes taking place in the region. Federal agencies must
incorporate the best available information about global warming and its
impacts on the Arctic into all decisions directly or indirectly
affecting the Arctic. We must also reduce direct impacts on polar bears
and their habitat from shipping and industrial activities through such
measures as a moratorium on the expansion of such activities in areas
subject to U.S. control. Finally, because protecting the polar bear and
the Arctic is only possible with the cooperation of not only all Arctic
nations, but with the global community more broadly, we should initiate
and engage in proactive multilateral efforts to protect the Arctic and
its resources so they remain largely unspoiled for future generations
in a manner similar to what has been accomplished under the Antarctic
Treaty. Each of these measures is described in more detail below. All
are necessary if polar bears are to survive in the very different
Arctic we have given them.
A. Incorporate Global Warming into Federal Agency Decisions
Congressional action and new laws explicitly capping and reducing
CO2 and non-CO2 pollutants are clearly necessary
if we are to slow and ultimately reverse global warming and save the
Arctic and the polar bear. Nevertheless, existing law allows, and in
some cases requires, the executive branch to take significant action to
address the current and future impacts of global warming on vulnerable
human landscapes, natural ecosystems, plants and wildlife. Use of this
authority will benefit all imperiled species, including the polar bear.
Unfortunately, such statutory mandates have largely been underutilized,
ignored, or explicitly rejected by the current administration.
Existing laws governing federal agencies that relate to global
warming and the Arctic fall into three broad categories: laws requiring
the compilation and analysis of information relevant to decision-
makers; laws requiring the contribution of a given agency decision or
action to greenhouse gas emissions and global warming be analyzed and
in some cases mitigated; and laws requiring the changing status of
species and resources in a warming climate be properly considered in
decision-making. Several laws address more than one of these
categories. Examples of each, relevant to the polar bear, which the
administration has ignored or underutilized are briefly discussed
below.
Information-generating statutes:
The Global Change Research Act (GCRA) requires the administration
to provide to Congress and agencies an assessment of the trends and
effects of global climate change on the United States, to be updated
every four years. 15 U.S.C. Sec. 2936(2)-(3). The last such assessment
was prepared in 2000. The administration is under court order to
prepare a new assessment by May 2008, as the result of a lawsuit
brought by the Center for Biological Diversity, Friends of the Earth
and Greenpeace.
The Marine Mammal Protection Act (MMPA) requires regularly updated
stock assessment reports that summarize the current status of all
marine mammals subject to U.S. jurisdiction. 16 U.S.C. 1361 et seq.
Updated stock assessments for polar bears and walrus are two years
overdue. Stock assessments for ice-dependant seals relied upon by polar
bears for food, while regularly updated, do not incorporate recent
information on global warming and sea-ice declines.
Analysis of greenhouse gas emissions from federal actions:
The Outer Continental Shelf Lands Act (OCSLA) governs the leasing
of tracts for offshore oil development in federal waters, including
those areas of the Beaufort and Chukchi seas utilized by polar bears.
In approving the 2007-2012 Program covering all offshore leasing in the
U.S., the Secretary of Interior refused to quantify the greenhouse gas
emissions from the oil and gas expected to be produced under the
program and failed to monetize CO2 and non-CO2
pollutants in calculating the economic costs and benefits of the
program.
The National Environmental Policy Act (NEPA) requires the
preparation of an environmental impact statement analyzing all
significant impacts of proposed federal actions. Few NEPA documents for
significant greenhouse gas generating projects prepared to date analyze
the impacts of such emissions. None that we are aware of analyze the
impacts of greenhouse gas or black carbon emissions on Arctic warming
or the polar bear.
The Endangered Species Act (ESA) requires each federal agency to
ensure through consultation with the Fish and Wildlife Service that any
federal action does not jeopardize the continued existence of any
listed species or destroy or adversely modify its critical habitat. 16
U.S.C. 1536. To date, despite the fact that existing regulations
require consultation on any action ``directly or indirectly causing
modifications to the land, water, or air,'' 50 C.F.R. 402.02, no
federal agency has ever engaged in consultation regarding the impacts
of greenhouse gas emissions flowing from a given agency action.
Analysis of the changing Arctic in federal decision-making:
Each of the statutes mentioned above require informed decision-
making and the use of the best available science. Nevertheless, few if
any agency decisions directly affecting the polar bear's Arctic habitat
have properly taken into account the changing status of the species in
a melting Arctic. For example, in August 2006, the Fish and Wildlife
Service issued regulations under the MMPA allowing unlimited take of
polar bears from all oil and gas related activities in the Beaufort Sea
region for a period of five years. Despite a request from the Marine
Mammal Commission to consider the impacts of global warming in making
the required determination of ``negligible impact'' under the statute,
the Service issued the authorization assuming impacts would be similar
to those documented when similar authorizations were issued more than a
decade previously and prior to the substantial changes of sea ice and
polar bear population size and distribution evidenced by recent
scientific observations. See 71 Fed. Reg. 43926 (Aug. 2, 2006).
As the above examples demonstrate, management decisions directly
affecting the polar bear have not caught up with the science
demonstrating significant changes in the status of the species and its
Arctic ecosystem. As uninformed decision-making is often unwise
decision-making, the polar bear will continue to be harmed by federal
agency actions until and unless all relevant agencies start
incorporating the most recent information regarding global warming and
its impacts on the Arctic into their decision-making. Climate-informed
decision-making is already the law; now it needs to be translated into
action.
B. Reduce Other Stressors on Polar Bears and the Arctic
While a business-as-usual warming scenario would doom the polar
bear to extinction and render any other conservation efforts
irrelevant, saving the polar bear will require not just dramatically
changing greenhouse gas emission trajectories but also addressing other
cumulative threats to the species. While climate-informed decision-
making will probably be better decision-making, and will reduce
cumulative impacts to the polar bear, certain activities, no matter how
thoroughly vetted, should simply no longer be allowed in polar bear
habitat. Among these are activities that directly add black carbon to
the Arctic (e.g., shipping) and activities that directly disturb polar
bears and degrade their essential habitats (e.g., oil and gas
development).
In 2003 the National Research Council noted that ``[c]limate
warming at predicted rates in the Beaufort Sea region is likely to have
serious consequences for ringed seals and polar bears, and those
effects will accumulate with the effects of oil and gas activities in
the region.'' (NRC, 2003). Since the NRC report, both the impacts of
global warming on the polar bear and the cumulative impacts of oil and
gas activities have greatly accelerated. With the lease sales in the
Beaufort and Chukchi seas scheduled under the 2007-2012 Program, and
the ongoing rapid leasing and development of the NPR-A, the vast
majority of polar bear habitat subject to U.S. jurisdiction, whether at
sea or on land, is now open for oil and gas leasing and development.
See Figure 8 (Map of existing and proposed leases in the Beaufort and
Chukchi seas).
Polar bears in the Beaufort Sea and elsewhere are already
undergoing food stress, and as a consequence resorting to cannibalism
or simply starving (Amstrup et al., 2006; Regehr et al., 2006; Aars et
al., 2006). Cub survival is down (Regehr et al., 2006; Aars et al.,
2006). Denning has shifted from occurring mostly on ice to mostly on
land and numerous bears now congregate on land pending the fall freeze-
up of the sea-ice (Regehr et al., 2006; Aars et al., 2006). At the same
time, the Beaufort Sea coast is becoming increasingly industrialized.
This combination is potentially devastating for the species. Denning
bears with reduced fat stores from a shorter hunting season are both
more vulnerable to disturbance from oil industry activities and
increasingly dependant upon areas subject to such industrial
development. Similarly, hungry bears, trapped on land, are more likely
to wander into oil camps and facilities looking for food, where their
odds of being directly killed by humans acting in self-defense or being
exposed to oil and other chemicals increases dramatically.
In addition to direct impacts on polar bears, oil industry activity
also impacts their prey, such as ice seals which may be exposed to
seismic surveys, icebreakers and other disturbances which could either
harm these animals or render them less available for bears to hunt. Oil
industry activity also results in methane and black carbon emissions in
the Arctic from production activities, and of course substantial
CO2 emissions from the ultimate combustion of the recovered
oil and gas.
Given the rapidly changing Arctic, the precarious status of polar
bears, and the numerous adverse impacts of oil and gas industry
activities on the species, we believe that there should be a moratorium
on new oil and gas leasing and development in the range of the polar
bear. Such a moratorium should be implemented immediately and remain in
effect until and unless such activity can be demonstrated to not have
adverse impacts on the polar bear, and any greenhouse emissions
directly or indirectly associated with such activities are shown to be
consistent with a comprehensive national plan to reduce CO2
and non-CO2 pollutants to levels determined necessary to
avoid the continued loss of sea ice.
In addition to oil and gas activities, a growing cumulative threat
to the polar bear is likely to be increased shipping in the Arctic
which brings with it black carbon emissions, the risk of oil spills,
and direct disruption and disturbance of polar bears and their prey.
The U.S. should work in appropriate international fora such as the
International Maritime Organization and the Arctic Council to prevent
the establishment of new shipping routes in the Arctic. Simultaneously,
the U.S. should require that any vessel transiting Arctic waters
subject to U.S. jurisdiction utilize fuels and engine technologies that
minimize black carbon emissions (see, e.g., Ballo and Burt, 2007), and
apply for and operate consistent with take authorizations under the
MMPA and ESA so as to minimize direct impacts to polar bears and their
prey.
Finally, persistent organic pollutants (POPs) represent a
significant threat to polar bears and other Arctic species. As polar
bears operate in an increasingly food-stressed state, they are likely
to metabolize body fat containing unhealthy concentrations of POPs. The
impact of POPs on individual polar bears can have both lethal and sub-
lethal effects. As polar bear populations decline, and individual bears
become more vulnerable, the disruptive cumulative effects of POPs on
the species are likely to grow. Reduction or elimination of these
compounds, both through application of U.S. law and international
effort will likely provide substantial benefit to polar bears.
While many of the cumulative threats to the polar bear are subject
to direct regulation by the U.S. and can and must be addressed
immediately, the ultimate survival and recovery of the polar bear will
require international efforts, not just to reduce greenhouse gas
emissions and stabilize the climate system, but to protect the fragile
Arctic habitat upon which the polar bear depends.
C. Towards an International Arctic Protection Regime
Ultimately, the protection of the polar bear and its Arctic habitat
is the shared responsibility of not only the U.S., or even the five
Arctic nations with polar bear populations, but of the broader global
community. As global warming transforms and increases human access to
the Arctic, we must be as proactive as possible in protecting this
area. Since much of the Arctic is beyond any country's control, and
many portions are now contested by competing national claims, a key
component of an Arctic protection strategy rests in the international
arena (See Figure 9). Just as the Antarctic Treaty arose in the context
of competing national claims to that continent, the territorial
disputes that are shaping up in the Arctic as the sea ice recedes and
commercial exploitation of the region becomes foreseeable, present not
just a threat, but an opportunity. Given we are entering the
International Polar Year, the time is ripe to push for international
action to permanently protect the shared treasure of the Arctic. The
U.S. should proactively promote the large-scale protection of the
Arctic through all existing international mechanisms, including the
International Agreement for the Conservation of Polar Bears, the Arctic
Council, and the United Nations Convention on the Law of the Sea. The
U.S. cannot remain a spectator as other nations compete to divide up
the resources of a newly accessible Arctic. We need to become
participant, not to stake our own claims, but to lead efforts to render
any such claims irrelevant, and shepherd the Arctic and the polar bear
through the rapid changes of the coming decades.
IV. Conclusion
We are committed to saving the polar bear from the ravages of
global warming for its own sake, as well as ours. Because the Arctic is
the Earth's early warning system, what is happening to the polar bear
now is a harbinger of what will happen to the rest of the world if
business-as-usual politics and emissions continue. We cannot allow this
to happen. It is not too late to save the Arctic-if we take action
today. Immediate reductions in both CO2 and non-CO2
pollutants, along with protection of the Arctic from direct physical
incursions, offer a true window of opportunity and hope. Acting to
reduce greenhouse emissions in a timeframe rapid enough to save the
polar bear will also provide us with the necessary urgency to tackle
the challenge of global warming before its impacts drown not only polar
bears but entire cities. We must begin immediately.
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APPENDIX A:
Mitigation Strategies for Non-CO2 Pollutants
The primary non-CO2 pollutants are methane, black carbon
(soot), nitrous oxide, and the high global warming potential gases
(Figure 4). The global warming potential of each of these pollutants is
more powerful than carbon dioxide--21 (methane) to 23,000 (sulfur
hexafluoride) times as powerful over a 100 year period (Forster and
Ramaswamy, 2007). The duration over which each of the gases is present
in the atmosphere and contributing to the greenhouse effect varies from
12 years (methane) to centuries (fluorinated gases). For ease of
comparison, the volume of each pollutant is expressed throughout this
report as its ``carbon dioxide equivalent'' in millions of metric tons.
Thus, one million metric tons of methane is equivalent to 21 million
metric tons of CO2 equivalent (MtCO2eq).
A. Methane
Methane is the most important of the non-CO2 pollutants,
with a global warming potential 21 times greater than carbon dioxide,
and an atmospheric lifetime of 12 years (Forster and Ramaswamy, 2007).
Methane constitutes approximately 20 percent of the anthropogenic
greenhouse gas effect globally, the largest contribution of the non-
CO2 gases. However, methane emissions anywhere in the world
will have a disproportionate warming impact in the Arctic, due to the
fact that methane is also an ozone precursor. Tropospheric ozone,
unlike other greenhouse gases, absorbs both infrared radiation and
shortwave radiation (visible light). Thus, tropospheric ozone is a
particularly powerful greenhouse gas over highly reflective surfaces
like the Arctic, because it traps shortwave radiation both as it enters
the Earth's atmosphere from the sun and when it is reflected back out
again by snow and ice. Reducing global methane emissions will reduce
ozone concentrations in the Arctic, providing a double benefit to the
region.
According to conservative projections by the U.S. EPA, about 500
MtCO2eq of global methane emissions reductions could be
achieved globally by 2020 at a cost benefit or no cost (EPA, 2006;
Table 4, Figure 7). Nearly 70 MtCO2eq of these available
reductions are in the United States (EPA, 2006; Table 2, Figure 6). The
EPA estimates total technically feasible methane reductions for 2020 at
over 2400 MtCO2eq globally and nearly 280 MtCO2eq
in the U.S., many of which can be achieved at low cost (EPA, 2006;
Tables 2 and 4; Figures 6,7).
The EPA's cost projections are conservative for a number of
reasons, including the use of a 10 percent discount rate. Using a lower
discount rate would result in additional cost benefit or no-cost
reductions. Moreover, the EPA analysis does not account for the value
of significant air quality and health benefits that would accompany
methane reductions. West et al. (2006) found that reducing global
methane emissions by 20 percent would save 370,000 lives between 2010
and 2030, due to the reduction in ozone related cardiovascular,
respiratory, and other health impacts. Methane reductions would also
decrease ozone-related damage to ecosystems and agricultural crops
(West et al., 2006). Methane is the primary component of natural gas,
and many abatement options include the use of captured methane to
generate energy. The benefits of displacing other fossil fuel energy
sources with captured methane are also not captured in the EPA (2006)
analysis.
While EPA (2006) may underestimate available no-cost and low cost
methane (and other non-CO2 gas) mitigation options, even
this conservative analysis shows the enormous opportunities available
to us today (Tables 1-4; Figures 6-7). These reductions can be achieved
with technology available today. Moreover, mandatory greenhouse gas
regulation will speed the development and deployment of new technology
and mitigation options, making much deeper reductions feasible in the
very near future.
1. The Waste Sector
Methane produced in the waste sector comes from two main sources:
landfills and wastewater. Landfills produced approximately 12 percent
of all global methane emissions in 2000. Landfills provide one of the
largest single sources of available emissions reductions, as the EPA
(2006) estimates that 88 percent of landfill methane emissions could be
abated with existing technology. Methane is produced in managed
(sanitary) landfills due to the anaerobic decomposition of organic
waste. Approximately 50 percent of landfill gas is methane and the
other 50 percent is largely made up of carbon dioxide. Sanitary
landfills are found predominately in developed countries. Open dumps
that do not promote anaerobic conditions are more common in developing
nations, but these countries are rapidly adopting landfill management
techniques because of the many advantages of sanitary waste disposal.
In the U.S., large landfills with capacity exceeding 2.5 megagrams (2.8
million short tons) are regulated under the Clean Air Act.\1\ Despite
the current programs in place, the U.S. is the largest source of
landfill methane in the world, producing in 2000 nearly three times as
much landfill emissions as the next largest producer, China (EPA, 2006:
III-5).
---------------------------------------------------------------------------
\1\ In March of 1996, EPA promulgated guidelines (61 Fed. Reg.
9905) for controlling the emissions from existing Municipal Solid Waste
landfills and the New Source Performance Standards for new or modified
Municipal Solid Waste landfills under authority of Section 111 of the
Clean Air Act. Although there are some differences in requirements for
landfills constructed or expanded under different stages of the
development of the regulations, in general the guidelines required the
following:
1) Installation of gas collection and control systems for new and
modified landfills designed to hold 2.755 million tons or more of waste
over their lifetime, and that could be expected to emit more than 50
---------------------------------------------------------------------------
megagrams per year of non-methane organic compounds (NMOC).
2) When any landfill reaches the above thresholds, it must within 30
months install a gas collection and control system that covers all
portions of the landfill. The collected landfill gas must be combusted
at a high enough temperature to destroy 98 percent of the toxics.
3) Three conditions be met prior to capping or removal of the
collection and control system: (1) The landfill must be permanently
closed; (2) the collection and control system must have been in
continuous operation a minimum of 15 years; and (3) the annual NMOC
emission rate routed to the control device must be less than 50
megagrams per year.
Landfill methane can be abated either through capture and flaring
or use for energy generation, or by diverting organic material from
landfills and into composting and recycling-reuse programs. Landfill
gases are already captured and flared at a number of U.S. landfills. A
preferable option is to use the methane directly for electricity or
heat generation, or to sell it to industrial users for energy use (EPA,
2006). Using methane for energy generation, as opposed to simply
flaring it, has the additional benefit of displacing the emissions that
would have resulted from otherwise supplying the energy created.
The second source of waste emissions is wastewater. Wastewater
contributes approximately nine percent of global methane emissions
(EPA, 2006). Domestic wastewater processing involves removing organic
matter, solids, pathogens, and chemicals. These produce a biomass
``sludge'' that is digested either anaerobically to produce methane, or
aerobically to produce carbon dioxide. Approximately 45 percent of the
sludge is usually digested, and the remainder is sent to landfills. The
amount of methane produced is proportional to the organic content of
the sludge.
Industrial sources with especially high organic content include
meat and poultry processing, pulp and paper processing, and produce
processing industries. The EPA estimates that 77 percent of meat and
poultry wastewater degrades anaerobically due to use of lagoons.
Similarly, lagoons are used for pulp and paper processing.
The abatement options for wastewater include: (1) reduced anaerobic
digestion and (2) collection and subsequent flaring or utilization.
Reductions in anaerobic digestion can be accomplished through aeration
and reduced usage of settling lagoons. Collection is used in series
with an anaerobic digester. The collected methane can be flared, or
preferably used for energy generation. EPA (2006) states that because
most centralized wastewater treatment facilities already either flare
or use captured methane for safety reasons, the ``add-on'' abatement
options to existing systems are limited. Large abatement opportunities
depend primarily on the creation of managed wastewater treatment
systems in developing countries, which will require large-scale
structural changes in wastewater management practices (EPA, 2006).
Because the primary motivation for the installation of improved
wastewater treatment has historically been the direct public health
benefits from disease prevention, EPA (2006) did not calculate cost
estimates. The increasing use of centralized wastewater treatment
facilities worldwide is clearly necessary and will bring enormous
benefits both for public health and climate change mitigation.
2. The Energy Sector
Enormous methane mitigation potential exists in the energy sector.
The three main sources globally are natural gas systems (16 percent of
total methane emissions), coal mining (six percent) and oil (0.95
percent). Abatement opportunities from natural gas systems are
particularly promising as natural gas is a rational transition fuel as
the global economy is decarbonized. Oil is more carbon-intensive than
natural gas, and coal the most carbon-intensive of all. Coal-fired
power plants, and therefore coal mining, must be reduced and then
eliminated. Nevertheless, methane abatement opportunities currently
exist and should be implemented wherever mining continues. Mitigation
opportunities are also available for abandoned coal mines.
The United States is the top consumer of natural gas and is second
only to the Russian Federation in methane emissions from natural gas
systems. Methane emissions occur during production, processing,
transmission and storage, and distribution of natural gas. There are a
variety of mitigation options that address each of these stages.
During extraction, the gas is passed through dehydrators to remove
water and other liquids. It is then transported through lines to a
processing facility for further refinement. The processed gas, which is
95 percent methane, is then compressed and transmitted to storage and
distribution facilities. Finally, the gas is decompressed to be
distributed for home or commercial use.
Leakage from lines and equipment is the main source of methane
emissions. These emissions can be abated through a variety of methods,
which can be broadly categorized as changes in operational practice,
equipment upgrade and replacement, and though direct inspection and
maintenance. A number of these measures will actually save the operator
money, on the order of 20-25$/tCO2eq (EPA, 2006:II-27).
The second largest source of energy sector methane emissions is
coal mining. Methane is produced as organic matter turns to coal. It
accumulates in pockets near a coal seam, and is eventually released
during the mining process. More methane is produced by deeper seams.
Because methane is dangerous, it is extracted and usually vented to the
atmosphere. Some methane is also produced during coal processing and
from abandoned mines.
Abatement of mining-related emissions may be through one of three
broad methods: (1) degasification, where methane is captured but not
vented prior to operations; (2) enhanced degasification, which involves
special drilling techniques and capture and use of methane; and (3)
oxidation of ventilation air methane (VAM) to produce energy (EPA,
2006). Approximately 57 percent of the methane obtained through
degasification--the drilling of wells or boreholes prior to mining--can
be piped out and sold for energy. If additional enrichment techniques
are used to further refine the methane obtained during degasification,
called enhanced degasification, approximately 77 percent of the methane
may be sold for energy. Finally, approximately 97 percent of
ventilation air methane, which is a much lower concentration, can be
mitigated through oxidation and use for local energy. Due to its low
concentration of methane, this gas is not suitable for distribution.
Because the captured methane can be used or sold for energy,
approximately 17 percent of emissions can be abated at no cost or
positive economic benefit. At a cost of less than 15$ per
tCO2eq, approximately 80 percent of emissions from coal
mining could be eliminated. Profitable options have been addressed in
EPA's Coalbed Methane Outreach Program started in 2001 to reduce and
use coal mine methane (http://www.epa.gov/cmop/resources/
webbrochure.html).
The third major energy-sector source of methane is oil production.
Fugitive emissions are released during crude oil production,
transportation, and refining (EPA, 2006). Oil production accounts for
approximately 97 percent of these methane emissions. Methane emissions
from onshore oil production are more easily captured and transported
than those from offshore production.
The major sources of production emissions are: volatilization of
high pressure crude oil as it enters the holding tank, equipment leaks
and vessel blowdowns (removal of liquids through pressurization), and
fugitive leaks and combustion during flares (EPA, 2006).
There are three abatement options: (1) flaring instead of venting;
(2) direct use for energy; and (3) reinjection of the methane to the
oilfield to enhance later oil recovery. Safety considerations make
flaring more feasible at onshore facilities. This measure has the
potential to reduce methane emissions by 98 percent over 15 years.
Flaring is the least preferred mitigation option as it does not produce
energy, thereby displacing other emissions, yet results in additional
CO2 emissions. The second option is the direct use of the
methane for energy at offshore platforms, and has the potential to
reduce 90 percent of methane emissions. The third option is to re-
inject the methane into the oilfield. This can reduce methane emissions
by 95 percent over 15 years.
3. The Agricultural Sector
Agriculture accounts for approximately 52 percent of global methane
emissions, and these are expected to increase by 30 percent in 2020
(over 2000 levels). The main agricultural sources of methane are rice
fields and livestock. Methane emissions from rice fields occur due to
anaerobic decomposition of organic matter in flooded rice fields. The
majority (90 percent of emissions) of rice production occurs in Asia.
Management practices that include variation in the timing of field
flooding, tilling practices, and fertilization can reduce the amount of
methane production.\2\
---------------------------------------------------------------------------
\2\ Some agricultural practices which reduce methane emissions lead
to an increase in nitrous oxide production, and thus mitigation options
must be carefully tailored so that only measures resulting in a net
decrease in greenhouse gas emissions are implemented.
---------------------------------------------------------------------------
The second major source of agricultural methane is livestock. This
includes both methane gas emitted by ruminants as a result of digestion
(enteric fermentation) and methane emitted by manure. While all
ruminants produce some methane, the majority of global methane emitted
due to enteric fermentation comes from cows used for beef and dairy
production. Switching to higher quality feed and lower volumes of feed
can reduce methane from enteric fermentation because high quality feed
increases the proportion of energy that is available for use by the
animal and consequently reduces the amount that is wasted as
methane.\3\ As a result, these mitigation options actually have a net
economic benefit for the producer.
---------------------------------------------------------------------------
\3\ High-energy feed, such as grain, can also increase the methane
produced by the manure. However, the need for a trade-off between lower
enteric fermentation emissions and manure emissions will be eliminated
if manure emissions are mitigated through the use of digesters.
---------------------------------------------------------------------------
Methane is also produced by manure during anaerobic decomposition.
These conditions occur when liquid manure is stored in lagoons, ponds,
tanks, and pits. The trend in the U.S. is to increasingly store manure
under these conditions. Furthermore, duration of time stored in this
manner and temperature affect the amount of methane that is produced.
The mitigation options for manure methane involve different types
of methane digesters that can capture the methane and produce energy. A
manure digester is a system of containers to collect and biologically
treat manure with naturally occurring microorganisms. The anaerobic
environment facilitates the generation and capture of methane. The
methane can then be burned to convert to CO2, and to produce
heat and/or electricity. Digesters may also include systems to collect
and separate solids. Large-scale digesters can be used for capture and
off-site energy use while temperature digesters can be used at smaller
facilities where the energy is used on-site.
C. Black Carbon or Soot
Black carbon, or soot, consists of particles or aerosols released
through the burning of fossil fuels, biofuels, and biomass (Quinn et
al., 2007). Black carbon warms the atmosphere, but it is a solid, not a
gas. Unlike most greenhouse gases that warm the atmosphere by absorbing
longwave infra-red radiation, soot warms the atmosphere by absorbing
visible light (Chameides and Bergin, 2002). Black carbon is an
extremely powerful greenhouse pollutant. Scientists have described the
average global warming potential of black carbon as about 500 times
that of carbon dioxide over a 100 year period (Hansen et al., 2007; see
also Reddy and Boucher, 2007; Bond and Sun, 2005). This powerful
warming impact is remarkable given that black carbon remains in the
atmosphere for only about four to seven days, with a mean residence
time of 5.3 days (Reddy and Boucher, 2007).
Black carbon contributes to Arctic warming through the formation of
``Arctic haze'' and through deposition on snow and ice, which increases
heat absorption (Quinn et al., 2007; Reddy and Boucher, 2007). Arctic
haze results from a number of aerosols in addition to black carbon,
including sulfate and nitrate (Quinn et al., 2007). Arctic haze may
either increase or decrease warming, but when the haze contains high
amounts of soot, it absorbs incoming solar radiation and leads to
heating. In addition, aerosols may interact with clouds changing
droplet number and size, which in turn can alter albedo, or
reflectivity.
Soot also contributes to heating when it is deposited on snow
because it reduces reflectivity of the white snow and instead tends to
absorb radiation. A recent study indicates that the direct warming
effect of black carbon on snow can be three times as strong as that due
to carbon dioxide during springtime in the Arctic (Flanner, 2007).
Black carbon emissions that occur in or near the Arctic contribute the
most to the melting of the far north (Reddy and Boucher, 2007; Quinn et
al., 2007).
Reductions in black carbon therefore provide an extremely important
opportunity to slow Arctic warming in the short-term, and mitigation
strategies should focus on within-Arctic sources and northern
hemisphere sources that are transported by air currents most
efficiently to the Arctic. Conversely, allowing black carbon emissions
to increase in the Arctic as the result of increased shipping or
industrial activity, will accelerate loss of the seasonal sea ice and
extinction of the polar bear. Black carbon reductions will also provide
air quality and human health benefits.
Despite its significance to global climate change and to the Arctic
in particular, black carbon has not been addressed by the major reports
on non-CO2 gas mitigation, nor is it explicitly addressed in
current global warming bills in the 110th Congress. Black carbon
reductions are an essential part of saving the Arctic sea ice and the
polar bear, and should be addressed by Congress in this session.
The highest priority sources for regulation include the following:
diesel generators and residential stoves within the Arctic, ships
operating in or near Arctic waters, diesel truck and automobile
engines, and biomass burning.
Specific measures that should be implemented include replacing
diesel generators with alternative energy sources, improving the
efficiency and/or particulate matter traps on residential stoves, or
fuel switching in residential stoves.
Ships operating in or near Arctic waters can introduce black carbon
directly into the region and should therefore be stringently regulated.
One of the simplest ways to reduce black carbon emissions from ships is
simply to slow them down (Ballo and Burt, 2007:26). A ten percent
reduction in speed can result in a 23.3 percent reduction in emissions
(Ballo and Burt, 2007:27). Requiring ships to switch to cleaner, lower
sulphur content fuels will also reduce black carbon emissions (Ballo
and Burt, 2007:29). There are a variety of design changes available to
increase the efficiency of ships and therefore decrease their emissions
(Kleiner, 2007). Finally, shipping should be stringently limited in the
Arctic, as discussed above.
All diesel engines are a significant contributor to black carbon
emissions. Emissions from diesel cars and trucks should be more
stringently regulated (Jacobson, 2002). Abatement options include
upgrading vehicles, installing end of the pipe filters, better vehicle
maintenance, and buy out/buy back programs for super emitters.
Emissions reductions from biomass burning and other sources are
most important when the Arctic ice extent is relatively large (Quinn et
al., 2007), and therefore regulating both the amount and timing of
anthropogenic biomass burning can also reduce black carbon levels in
the Arctic.
Much more attention needs to be focused on identifying and
implementing black carbon emissions from all sources.
D. Nitrous Oxide
Unlike methane and black carbon, nitrous oxide and the high global
warming potential gases discussed below do not have a disproportionate
impact on the Arctic. Nevertheless, because these gases have high
global warming potential, long atmospheric lifetimes, and because there
are many readily available mitigation measures to reduce them, they
present important opportunities for reducing global warming overall and
are therefore an important part of saving the Arctic and the polar
bear.
Nitrous oxide has a global warming potential 310 times that of
carbon dioxide and an atmospheric lifetime of approximately 120 years.
It constitutes the second largest proportion of anthropogenic non-
CO2 gases at seven percent. The main sources of nitrous
oxide emissions are: agriculture, fossil fuel combustion, and
industrial adipic and nitric acid production.
1. Agriculture
Agriculture is the largest source of anthropogenic nitrous oxide
(84 percent) (EPA 2006). These emissions are projected to increase by
37 percent in 2020 (over 2000 levels). Agricultural nitrous oxide is
produced primarily (1) through the processes of nitrification and
denitrification of soil, (2) by livestock manure, and (3) from rice
farming.
Nitrous oxide emissions occur as a result of addition of nitrogen
to the soil through fertilization, nitrogen-fixing crops, retention of
crop residues, and cultivation of high organic content soil (peat or
histosol) (EPA, 2006). Nitrous oxide emissions can also result from
volatilization of applied nitrogen and runoff.
In 2000, the United States' soil nitrous oxide emissions were
second only to the former Soviet Union, and are predicted to surpass
the FSU by 2010. Practices such as irrigation, drainage, tillage, and
fallowing all influence nitrous oxide emissions.
An important consideration when selecting abatement options is that
a number of practices may reduce nitrous oxide emissions while
increasing carbon dioxide emissions, resulting in a net increase in
greenhouse gases. The abatement options presented below are those that
do not result in increased carbon dioxide emissions.
The options include reduced fertilization or more efficient
fertilization, and no-till management to maintain at least 30 percent
of the ground covered by crop residue after planting. The most
effective fertilization option is the use of a fertilizer that includes
a nitrification inhibitor. No-till, or conservation tillage, is
effective primarily because it reduces carbon loss. The net reductions
potential for croplands is approximately 24 percent, with 15 percent
possible at zero net cost.
Rice fields produce both methane and nitrous oxide. The cycle,
however, is different for each of the gases so that some methods that
reduce one gas may increase the other. Thus, management practices must
be considered carefully to balance the effects. Shallow flooding, off-
season straw, and ammonium sulfate are the management practices that
can reduce nitrous oxide emissions as well as methane emissions. The
practice of mid-season drainage reduces methane substantially while
increasing nitrous oxide. Yet, due to the magnitude of methane
reduction, this practice results in a net reduction of equivalent
greenhouse gases.
The final major agricultural source of nitrous oxide is livestock
manure. The practices outlined above for reductions in methane
emissions from livestock manure also apply to reductions in nitrous
oxide.
2. Industrial production
The production of nitric and adipic acid account for approximately
five percent of nitrous oxide emissions. Nitric acid accounts for
approximately 67 percent and adipic acid accounts for approximately 33
percent of emissions. Nitric acid is used in fertilizers as well as
explosives, metal processing, and etching. Adipic acid is a component
of nylon, synthetic lubricants and plastics, polyurethane resins, and
plasticizers. It is also used in some artificial foods to impart a
``tangy'' flavor.
Plants that produce nitric acid and do not employ nonselective
catalytic reduction may generate up to 19 kilograms of nitrous oxide
per ton of nitric acid. The majority of plants in the U.S. do not use
this technology, and approximately 80 percent of plants worldwide do
not use it. Nitric acid plants can reduce their emissions by 90 to 95
percent through high-temperature or low-temperature catalytic
reduction. The costs are minor: approximately $2-$6/tCO2eq.
The high-temperature option is less expensive and reduces nitrous oxide
by 90 percent. The low-temperature option costs slightly more and
reduces emissions by 95 percent.
The abatement option for adipic acid plants is thermal destruction.
This option costs only $0.50/tCO2eq and can reduce nitrous
oxide emissions by 98 to 99 percent.
E. High Global Warming Potential Gases
High global warming potential (High-GWP) gases fall into three
broad categories: hydrofluorocarbons (HFCs), perfluorcarbons (PFCs),
and sulfur hexafluoride. Hydrofluorocarbons were developed to replace
ozone-depleting substances used in refrigeration and air conditioning
systems, solvents, aerosols, foam production, and fire extinguishing.
HFCs have global warming potentials between 140 and 11,700 times that
of carbon dioxide, and their atmospheric lifetimes range from one year
to 260 years, respectively.
Perfluorocarbons are emitted during aluminum production and
semiconductor manufacture (EPA, 2006). Their global warming potential
ranges from 6,500 to 9,200 times that of carbon dioxide. In addition,
they have extremely long atmospheric lifetimes, e.g., 10,000 and 50,000
years for two common PFCs.
The highest global warming potential exists in sulfur hexafluoride
at 23,900 times that of carbon dioxide. Sulfur hexafluoride remains in
the atmosphere for 3,200 years. Sulfur hexafluoride is used: (1) for
insulation and current interruption in electrical power transmission
and distribution; (2) during semiconductor manufacture; (3) to protect
against burning in the magnesium industry.
1. Hydrofluorcarbons
a. Refrigeration and Air Conditioning
Hydrofluorocarbons are used for refrigeration and air conditioning,
solvents, foam manufacture, aerosols, and in fire extinguishers. The
emission of hydrofluorocarbons related to refrigeration occurs during
manufacturing and servicing, leaks during operation, and disposal. An
indirect effect of using these systems is the use of energy and
resulting emission of carbon dioxide. Thus, mitigation measures should
be evaluated both for direct HFC emissions as well as carbon dioxide
emissions.
There are a variety of uses for refrigeration systems: household
refrigeration, car air-conditioning, chillers for large spaces such as
shopping malls as well as submarines and nuclear reactors, retail food
refrigeration, cold storage warehouses, refrigerated transport,
industrial refrigeration during manufacture, and residential and
commercial air conditioning and heat pumps. Because a number of these
systems currently use ozone-depleting substances that are being phased
out as equipment ages, the impact of switching systems has been
incorporated into the mitigation analysis (EPA, 2006).
The abatement options fall into three categories: practice options,
alternative refrigerant options, and technology options. Practice
includes actions such as leak repair, refrigerant recovery/recycling,
and sales restrictions on HFCs. The alternative refrigerants include
ammonia, hydrocarbons such as isobutene, and carbon dioxide.
Many of the abatement options carry a net economic benefit, such
that the U.S. alone could reduce over 20 metric tons CO2eq
emissions by the year 2020 at no cost or at a net economic benefit.
b. Solvents
Solvents used in precision and electronic cleaning, and to a much
lesser extent metal cleaning, have replaced ozone-depleting substances
in a variety of ways, including substitution of HFCs and PFCs. There
are three main mitigation options: (1) improved solvent containment and
use of carbon absorption; (2) use of aqueous or semi-aqueous cleaning
processes; and (3) conversion to different low-global warming potential
compounds or organic compounds.
The conversion to alternative compounds is a no-cost abatement
option that could reduce baseline emissions by approximately 25 percent
by the year 2020. Similarly, conversion to semi-aqueous cleaning
processes would only cost approximately $0.67/tCO2eq.
c. Foam manufacture
HFCs are used during the blowing process to produce foam. These
emissions are expected to rise dramatically in coming years. Another
ozone-depleting substance, hydrochloroflurocarbons (HCFCs), is still in
use in developing countries, but will be phased out with time. The U.S.
currently allows the use of HCFC-22, but not HCFC-141b.
Emissions occur during the manufacture process, during foam
application, while foams are in use, and when they are discarded.
Abatement can be achieved through replacement of the blowing agent used
in the manufacture process and proper disposal of appliance foam at
end-of-life. Several of the replacement options would bring a net
economic benefit. The total possible reduction from the predicted 2020
baseline emissions is approximately 31 percent.
d. Aerosols
Aerosols are used to propel a variety of products. After CFCs were
banned in the U.S., some products began using HFCs as propellants.
Medical applications, such as inhalers, currently still use CFCs, but
these companies are developing HFC alternatives.
Abatement of non-medical HFC emissions involves replacing current
HFCs with other HFCs that have a lower global warming potential,
hydrocarbon propellants, and other application methods such as hand
pumps, roll-on applicators, and powders. All of these non-medical
options can be achieved at no cost and would reduce current HFC
emissions by at least 57 percent in the year 2020.
Transitioning away from CFCs has proven to be a challenge with
medical inhalers. One alternative for some patients, however, is the
use of dry powdered inhalers. The use of this application method has
the capability of reducing medical propellant HFC emissions by half.
e. Fire Extinguishing
Halon was traditionally used in fire extinguishing systems--both
portable fire extinguishers and ``total flooding'' systems that protect
large spaces. Due to its ozone depleting characteristics, halon is
being replaced in some instances with HFCs.
Depending on the application, HFC systems can be replaced by inert
gas systems, water mist systems, or fluorinated ketone systems. In
addition, abatement can be achieved through recovery and reuse of HFCs
and through improved detection mechanisms to prevent erroneous release
in total flooding systems.
f. HCFC-22
As mentioned above, HCFC-22 is an ozone depleting substances that
is used in refrigeration, some solvents, and synthetic polymer
production. One of the byproducts is HFC-23, which has a global warming
potential of 11,700 times that of carbon and an atmospheric lifetime of
260 years. The U.S. is close behind China as the second largest
producer of HFC-23 emissions resulting from production of HCFC-22.
There are several options for mitigating HFC emissions.
Manufacturing optimization can maximize HCFC-22 production and minimize
HFC-23 production at very lost cost. Thermal oxidation of HFC-23 by
product can reduce 95 percent of HFC emissions. Oxidation costs only
about $0.23/tCO2eq and can reduce HFC emissions at existing
plants by 88 percent, even assuming that current plans to minimize
HCFC-22 are implemented.
At the commemoration meeting of the Montreal Protocol on September
21, 2007, the U.S. and other developed nations agreed to a schedule of
reductions that includes ceasing to use HCFCs by 2020, which is 10
years sooner than previously agreed. Thus, the assumptions upon which
the EPA 2006 report were based may be inapplicable.
2. Perfluorocarbons
a. Aluminum production
The aluminum industry is the largest source of PFC emissions. PFCs
are emitted when so-called anode effects occur during the smelting
process. The amount of PFCs emitted depends directly on the number and
duration of such events.
Although the aluminum industry has taken voluntary reductions and
has pledged further reductions, there are still mitigation options that
should be implemented to further reduce emissions. The two main methods
are: installation of computer control systems and installation of
alumina point-feed systems. The computer control system is considered a
minor retrofit and the alumina point-feed system is considered a major
retrofit. The efficacy of these measures depends on the current
technology used by the plant. They may reduce PFC emissions by up to 97
percent when combined at some facilities. The implementation of these
options can also come at an economic benefit in some facilities.
b. Semiconductor manufacturing
The manufacture of semiconductors releases PFCs, sulfur
hexafluoride, and HFC-23 primarily during plasma etching of thin films
and cleaning chemical-vapor-deposition (CVD) chambers. Etching is
estimated to account for approximately 20 percent of emissions, while
CVD chamber cleaning accounts for approximately 80 percent. PFC
emissions also occur as a by-product of reactions between other gases.
The U.S. is the second largest emitter of PFCs, although it is a member
of the World Semiconductor Council, which has committed to voluntary
reductions in emissions.
The most effective abatement option is nitrogen trifluoride remote
cleaning technology. This system can reduce emissions by approximately
95 percent. This option has a net economic benefit and when implemented
could reduce baseline emissions by 42 percent, even assuming the
industry meets its voluntary emissions reduction goal. The second most
effective option is point-of-use plasma abatement during the etching
process.
3. Sulfur hexafluoride
a. Electrical industry
Sulfur hexafluoride is primarily emitted by the electrical
industry. Sulfur hexafluoride is used as a dielectric insulator in
transmission lines, sub-stations, and transformers. The United States
is the largest emitter of sulfur hexafluoride. The electric industry
has recently begun reducing its sulfur hexafluoride emissions, however
much more remains to be done.
Sulfur hexafluoride emissions can be reduced through sulfur
hexafluoride recycling, leak detection and repair, and equipment
refurbishment. Recycling presents the greatest opportunity for
mitigation, with a net economic benefit and potential for emissions
reduction of approximately 43 percent above and beyond currently
planned reductions. Many companies already recycle sulfur hexafluoride.
The average efficacy of their systems is 80 percent, but this could
easily be increased to provide for 95 percent reductions in sulfur
hexafluoride emissions. Leak detection and repair can reduce emissions
that occur during operation. Finally, equipment refurbishment can also
reduce emissions.
b. Magnesium production
Sulfur hexafluoride is currently used as a cover gas during
magnesium production to prevent spontaneous combustion. Essentially all
of the sulfur hexafluoride is emitted into the atmosphere. The
International Magnesium Association, representing 80 percent of the
industry, has pledged to eliminate sulfur hexafluoride by 2011. They
will do so by substituting different cover gases.
Emissions can be abated by replacing sulfur hexafluoride with
either sulfur dioxide or fluorinated gases. New technology has solved
the toxicity, corrosion, and odor concerns associated with sulfur
dioxide. Thus, it is can fully eliminate emissions that contribute to
global warming, and is relatively inexpensive. The replacement of
sulfur hexafluoride with fluorinated gases is also possible, although
these gases still have global warming effects.
Biography for Kassie R. Siegel
Kassie Siegel is Director of the Climate, Air, and Energy Program
at the Center for Biological Diversity, a non-profit membership
organization which c ombines conservation biology with litigation,
policy advocacy, and an innovative strategic vision in working to
secure a future for animals and plants hovering on the brink of
extinction, for the wild areas they need to survive, and by extension
for the physical, spiritual, and cultural welfare of generations to
come.
Siegel is a graduate of the Boalt Hall School of Law at the
University of California, and has worked for the Center for Biological
Diversity since 1998. She develops and implements campaigns and
strategies for the reduction of greenhouse gas pollution and the
protection of wildlife threatened by global warming, and also litigates
cases addressing global warming under federal and State law.
Siegel is the author of the Petition submitted by the Center for
Biological Diversity in February 2005 seeking protection of the polar
bear under the Endangered Species Act, and lead counsel of the lawsuit
filed in December 2005 by the Center, Greenpeace and NRDC to compel the
Bush Administration to respond to the Petition, which resulted in the
January, 2007 proposal to list the polar bear as threatened under the
Endangered Species Act. She has drafted similar petitions for other
species threatened by global warming, such as twelve of the world's
penguin species, including the Emperor penguin. Siegel is also a
volunteer presenter for the Climate Project.
SELECTED PUBLICATIONS AND PRESENTATIONS
Cummings, B., and K. Siegel (in press). Biodiversity, Global Warming
and the United States Endangered Species Act: The Role of
Domestic Wildlife Law in Addressing Greenhouse Gas Emissions.
In Adjudicating Climate Control: Sub-National, National, and
Supra-national Approaches (W.C.G. Burns and H.M. Osofsky,
eds.), Cambridge University Press.
Cummings, B., and K. Siegel. 2007. Ursus maritimus: Polar Bears on Thin
Ice. Natural Resources and Environment 22, Number 2, Fall
2007:3-7.
Siegel, K. `CEQA and Global Warming Matters' Private Enforcement of
Environmental Law: Prosecuting and Defending Citizens' Suits,
The Environmental Law Section of the State Bar of California,
May 2007, Oakland, California.
Siegel, K., R. Fairbanks, and S. Sakashita `Global Warming and
Biodiversity,' 25th Annual Public Interest Environmental Law
Conference, March 2007, Eugene, OR.
Siegel, K. `Global Warming, Biodiversity, and the Endangered Species
Act,' Environmental Law Conference at Yosemite, The
Environmental Law Section of the State Bar of California,
October 2006, Fish Camp, California.
Siegel, K. `The No Surprises Litigation,' The Endangered Species Act
Conference, CLE International, June 2004, Santa Barbara, CA.
BAR MEMBERSHIPS
Active member of California Bar (No. 209497);
admitted to practice before the California Supreme Court, the
U.S. District Courts for the Northern, Southern, Central, and
Eastern Districts of California, and the U.S. Court of Appeals
for the Ninth Circuit.
Inactive member of Alaska Bar (No. 0106044); admitted
to practice before the Alaska Supreme Court.
Discussion
Relation of Astrophysics to the Arctic and Polar Bears
Chairman Miller. Thank you, Ms. Siegel. I now recognize
myself for an initial round of questions.
There was a Congressional Delegation, a Co-Del, of Members
of this committee a couple months ago to Greenland; and I was
part of the delegation, and it was striking. The scientists we
talked to came from a variety of what appeared to be different
disciplines that all intersected, the Arctic. They all called
themselves snow and ice guys, but their disciplines were
varied; and it took me a while to realize yes, that does have
an intersection with research on the Arctic. Now, they also
appeared to be kind of members of a fraternity. They all knew
each other, knew each other's work, they'd hung out together
probably in the few bars there are in Greenland, so they were
familiar with each other's work.
There is a recent paper on polar bears that paints a much
more optimistic picture, Ms. Siegel, or Dr. Haseltine. And one
of the authors is an astrophysicist which I have got to say
still does not strike me. I still do not see the intersection
of astrophysics and polar bears or the Arctic, but perhaps
there is one that I am missing. The paper was by Dike and
Willie Soon and Willie Soon is apparently an astrophysicist. Is
astrophysics one of the disciplines that has an intersection
with research in the Arctic or into polar bears? Dr. Alley? Dr.
Juday? Dr. Haseltine?
Dr. Haseltine. I have to say that we have an astrophysics
branch at USGS that works with NASA, and we didn't use their
models in projecting polar bears.
Chairman Miller. I took that as a delicate way of saying
no, you didn't really think astrophysics had a particular
application in modeling--any of the rest of you know of any
work being done by astrophysicists that pertain to projections
of the climate and the arctic and the effect on polar bears?
Dr. Alley. There has been a long interest in trying to sort
out what of the changes that are occurring are natural and what
of the changes occurring are human caused, and astrophysics
feeds into this from one side because very clearly changes in
the sun will affect the climate strongly. And there are
hypotheses that are not very well validated that changes in
cosmic rays or other things will matter. And so we do talk to
astrophysicists on the climate end, and their output has been
assessed and included in the work of the National Academy or
the IPCC in saying with high confidence that the recent changes
we see in the Arctic are not astrophysical, they are us.
Chairman Miller. How about specifically the effect on polar
bears?
Dr. Alley. I personally--normally when I get to the point
of talking about biology, I get a big smile on my face and I
show pretty pictures of what I have seen, but I turn to an
expert.
Chairman Miller. Okay. And I assume that all of you kind of
knew each other before this? You didn't meet the first time
tonight, today, is that correct? Okay. You knew of each other?
Knew each other by reputation at least, even if you hadn't had
beers together in a bar on the Bering Sea. Are you familiar
with Dr. Willie Soon other than from the recent paper, from
research in this area?
Dr. Juday. Yes, I try to keep up with the community in what
is sometimes called the climate skeptics, and he has been
prominent there. Sometimes I get good ideas of how to test some
of what I think I am finding and take a more skeptical eye
toward it.
Chairman Miller. Ms. Haseltine, you look like you are ready
to say something on this topic? Ms. Siegel, are you familiar
with this paper and what is your take on it?
Ms. Siegel. I am, Mr. Chairman, and I would like to point
out that the paper was funded by the Charles G. Kotch
Charitable Fund, American Petroleum Institute, and ExxonMobil,
and that that authors include discredited climate deniers
Willie Soon, David Legates, Sally Baliunas, and others. I would
also like to point out that it was published as a viewpoint in
the journal Ecological Complexity, not as a peer-reviewed
science article. This is essentially an op-ed masquerading as a
peer-reviewed science journal. The article was also based on
the assertion that there is no significant warming trend in
Western Hudson Bay, which is simply not true. Breakup now
occurs three weeks earlier in western Hudson Bay than it did 30
years ago. The sea ice is in fact declining in the Arctic. From
late spring to breakup is the most important hunting time for
polar bears when they eat large numbers of ringed seal pups.
They now have less time on the ice to hunt. Body condition and
cub survival have declined, and female polar bears that do not
reach a certain minimum body weight cannot reproduce. The
population has declined 22 percent from 1,200 bears in 1987 to
less than 950 bears in 2004. Leading polar experts have said
that suggestions that today's polar bear populations will be
able to obtain food sources to replace seals caught on the ice
surface is fanciful. Polar bears in western Hudson Bay during
the ice-free months are in a hibernation-like state, a
physiological state of fasting. They cannot replace extremely
energy-intensive seal blubber with berries and opportunistic
scavenging. Leading polar bear experts have stated that we must
quickly and significantly reduce greenhouse gas emissions in
order to save polar bears.
Chairman Miller. Thank you. My time has now expired. Mr.
Rohrabacher.
Ms. Siegel's Background
Mr. Rohrabacher. Thank you very much, Mr. Chairman. Ms.
Siegel, what is your degree in, educational background?
Ms. Siegel. I did my undergraduate work in anthropology and
economics, and I am an attorney.
Mr. Rohrabacher. You have an undergraduate degree in?
Ms. Siegel. Anthropology and economics from the College of
William and Mary in Williamsburg, Virginia.
Mr. Rohrabacher. I couldn't find that in your bio here. It
just states you went to Boalt Hall?
Ms. Siegel. Exactly, Boalt Hall at the University of
California.
Mr. Rohrabacher. Right, I know that. That is in Berkeley,
is it not?
Ms. Siegel. That is correct.
Mr. Rohrabacher. The Chairman quoted Mr. Hansen earlier,
Dr. Hansen, and I understand that Dr. Hansen has received a
substantial amount of money for his research from George Soros
who is a--of course to say is politically active is to put that
mildly. Has anyone else here or the organizations you are
associated with or you yourself received money from Mr. Soros
or his foundations to do your research or your activities? Has
your organization received any money from Mr. Soros?
Are Humans Causing Climate Change?
Ms. Siegel. Not to my knowledge.
Mr. Rohrabacher. Not to my knowledge. Very loyal answer.
There is no question obviously that the Earth is going through
a warming trend right now. There is no question about that. One
realizes that the Earth warming trends perhaps dozens of times,
and the major question is is this warming trend caused by human
activity. If it is not, should we not be looking at adapting
rather than arrogantly thinking that mankind can reverse what
has been a trend of nature over these many hundreds of
thousands, if not millions of years of the life of the planet?
Let me just say, and of course we are looking at the effects of
this in terms of polar bears, et cetera. One of the reasons
some of us like myself are skeptical of some of these things is
just that I remember very much the predictions of dire and doom
for the caribou. We ended up building a pipeline across Alaska,
and I don't have to ask you, you all know, that the caribou
population has drastically expanded since that pipeline,
although people were testifying before Congress and just as
adamant as yourselves that the caribou population was going to
be decimated by the fact that there would be a pipeline across
Alaska. And quite often we hear people with these dire
predictions in order to whatever, accomplish perhaps other
political ends. This might be more consistent with what Mr.
Soros has in mind. Let me ask you this. We know the ice cores
and these testings that give us an understanding of climate
change in the planet, apparently Dr. Timothy Ball, who is a
former climatology professor at the University of Winnipeg,
stated that the theory, and I quote, in theory the claim that
if CO2 goes up, temperature will go up is wrong. The
ice core record for the last 420,000 years shows exactly the
opposite, that indeed increases in the temperature bring about
more CO2, rather than CO2 increases
bringing about the increase in the temperature, which of course
leads directly to whether or not human kind is actually causing
this increase in temperature. Now, Dr. Juday was mentioning how
the methane gas is bubbling up as the temperature increases. It
seems to me your testimony backed up Dr. Ball's observation,
because what you were saying is that as the temperature has
gone up there is more methane being put into the atmosphere. It
would be wrong to say that methane increasing in the atmosphere
was causing the temperature to go up, is that not correct?
Dr. Alley. If I were to take my credit card and overspend,
I would go into debt and then I would start to make interest
payments which would contribute to my debt further. If your
accountant were to try to understand my debt based solely on my
over expenditures, your accountant would fail. If your
accountant included the interest payments that were triggered
by my going into debt, your accountant would succeed. What we
know very clearly is that the ice age cycles referred to by Dr.
Ball are caused by features of Earth's orbit.
Climate Change From the Earth's Orbit
Mr. Rohrabacher. By what?
Dr. Alley. Caused by features of Earth's orbit. Imagine
that you are the sun for the moment, this is the Earth. My
North Pole if it stood straight up would never get a sunburn
from your brightness, but because it is inclined, I can get a
sunburn on my North Pole; and the North Pole nods over 41,000
years, more sunburn, less sunburn. That plus a wobble and a
change in the shape of the orbit caused the ice age. But those
changes from the ice age caused changes in CO2 and
in methane, and when we try to explain the very large change in
temperature on the planet for the ice ages, if we assume that
CO2 and methane do not cause warming, no one has
ever explained how big the changes are in the same way that
your accountant could not explain my debt without including my
interest payments. If we use the warming that is expected from
the CO2 and the methane, we explain what happened.
And so in exactly the same way that the interest payments on my
debt contribute to my debt, it must be included to explain my
debt. The interest payments of CO2 coming up with
the warming contribute to further warming and must be included
to explain that warming.
Mr. Rohrabacher. I will have to admit that I don't
understand a thing that you just said----
Chairman Miller. You can ask further in the next round of
questions.
Mr. Rohrabacher.--but I will say that you did tend to
indicate that the climate change that we have seen in the past
at least was caused by changes, by the sun and by changes in
the Earth rather than by human activity.
Dr. Alley. Very clearly, the ice age cycle is not to our
credit. It is nature's.
Mr. Rohrabacher. Thank you.
Evidence of Climate Change
Chairman Miller. Dr. Juday I think does want to respond.
Dr. Juday?
Dr. Juday. Yeah, I was trying to get the point across that
there are these amplification mechanisms, and the initial push
can be in the short-term solar variability, volcanic eruptions
of the particular kind that can cool things down and the
coupled atmosphere marine circulation patterns. I have a slide
that is in the post-presentation phase there where I did a test
of this, and it is a long-term record. It starts in 1917, and
it shows the date of ice breakup on the Tanana River in Alaska.
The crews that were building the Alaska railroad got bored, and
so they did a lottery and so to the minute it has been done
exactly the same way ever since. And by accounting for just
exactly those factors, solar variability and solar cycle, there
have been El Ninos and the couple of really big volcanic
eruptions that we have had, take those out of that record, and
they have a dramatic impact. When it is supposed to be cold,
boy, we make it cold and the breakup is late; and when it is
supposed to be warm, boy, they make it warm. Take them out. And
what is left is a trend, and the only way to explain that trend
is there is some underlying process. If you look further at the
character of that process, what do you see? The daily high
temperatures haven't changed all that much. The daily low
temperatures have increased at the rate of three to three and
one-half degrees C per century. Our growing season length has
doubled. The winter temperatures have warmed.
So something is happening that is dampening heat loss, not
adding extra heat during the summer.
Mr. Rohrabacher. Doctor, the only question is whether it is
human-caused or not.
Dr. Juday. The characteristics are exactly the
characteristics of the way a greenhouse gas process works. So
it matches, and if there is a better theory, I would pursue
that.
Mr. Rohrabacher. The sun.
Dr. Hansen and George Soros
Chairman Miller. A couple points quickly. Dr. Hansen, I
understand, denies the allegation that he has gotten money from
George Soros. He is not here to defend himself. He is not a
witness here today. He is a scientist at NASA. My understanding
is that he is one of the world's leading climate scientists,
but he has been charged with having received money from Mr.
Soros, from George Soros. He says it is not true, and we have a
statement from him actually in which he said that that is not
true. So we will now enter that into the record.
[The prepared statement of Dr. Hansen follows:]
Prepared Statement of Dr. James Hansen
. . .And Other Forms of Lawlessness
27 September 2007
The latest swift-boating (unless there is a new one among seven
unanswered calls on my cell) is the whacko claim that I received
$720,000.00 from George Soros. Here is the real deal, with the order of
things as well as I can remember without wasting even more time digging
into papers and records.
Sometime after giving a potentially provocative interview to Sixty
Minutes, but before it aired, I tried to get legal advice on my rights
of free speech. I made two or three attempts to contact people at
Freedom Forum, who I had given permission to use a quote (something
like ``in my thirty-some years in the government, I have never seen
anything like the present restrictions on the flow of information from
scientists to the public'') on their calendar. I wanted to know where I
could get, preferably inexpensive, legal advice. Never got a reply.
But then I received a call from the President of the Government
Accountability Project (GAP) telling me that I had won the Ridenaur
Award (including a moderate amount of cash--$10,000 I believe; the
award is named for the guy who exposed the Viet Nam My Lai massacre),
and offering pro bono legal advice. I agreed to accept the latter
(temporarily), signing something to let them represent me (which had an
escape clause that I later exercised).
I started to get the feeling that there may be expectations
(strings) coming with the award, and I was concerned that it may create
the appearance that I had spoken out about government censorship for
the sake of the $. So I called the President of GAP, asking how the
nomination process worked and who made the selection. He mentioned that
he either nominated or selected me. So I declined the award, but I
continued to accept pro bono legal advice for a while.
The principal thing that they provided was the attached letter to
NASA. This letter shows me why scientists drive 1995 Hondas and lawyers
drive Mercedes. I have a feeling that the reader of that letter had at
least one extra gulp of coffee that morning.
But it turns out that GAP has lost most of their cases in defending
whistle-blowers. It is obviously not because they are crummy lawyers.
Things are getting pretty tough in our country. It is still not clear
to me what rights of free speech we actually have today.
Some people think that things must have changed in our government,
since I have been speaking pretty freely of late. That is mainly
appearance. The (free speech) situation in NASA is good at the moment
only because our Administrator made a strong statement. The rules as
written, according to GAP, will allow the next Administrator, if he so
desires, to hammer the free speaker. But the big problem is that the
Offices of Public Affairs in most agencies, at the Headquarters level,
have been staffed with political appointees, who in effect are running
Offices of Propaganda (Mark Bowen has written a book about this, which
will come out in December). Public Affairs people at the field centers
are dedicated professionals, but political appointees occupy the
Headquarters positions in Washington. I complained about this to a
Government Reform committee in the House (littp://www.columbia.edtL/
jehl/20070319105800-43018.pdf), saying that there should be a law that
Public Affairs must be staffed by professional civil servants, not
political appointees. I did not seem to raise much interest. Too much
reform for a Reform committee, I guess.
The bottom line is: I did not receive one thin dime from George
Soros. Perhaps GAP did, but I would be surprised if they got $720,000
(that's a lot of Mercedes). Whatever amount they got, I do not see
anything wrong with it. They are a non-profit organization. Seems like
a great idea to have some good lawyers trying to protect free speech.
By the way, in case anybody finds out that George Soros INTENDED to
send me $720,000 but could not find my address, please let me know! We
are pretty hard pressed here.
Scientists Named Steve
Chairman Miller. I have a peculiar question that may take
you a while to think about because we all know people named
Steve. It may take us a second to think of who they are. One of
the frustrations of dealing with what scientists think is that
there are so many scientists. But there is a science blog
called Panda's Thumb that has done kind of a canvas of the
scientists named Steve. I thought that that was a more workable
number of people. And when there is a dispute about what
scientists think, rather than try to canvas all scientists,
they try to canvas the scientists named Steve, an intriguing
idea and one that probably makes statistical sense. It is
probably a statistically valid sample. Do you know of any
climate skeptics who believe that either the globe's climate is
not changing, it is not warming, or that the cause is not human
activity named Steve? You can get back to us on that.
Dr. Alley. I am finding one right now.
Chairman Miller. How about scientists named Steve? Can you
think of scientists named Steve who believe that the world's
climate is changing and it is warming and it is resulting in
human activity, named Steve? Dr. Allen?
Dr. Alley. Steven Schneider Stanford would be a good
starting point.
Chairman Miller. Okay. Dr. Juday, any Steves come to your
mind?
Dr. Juday. Yeah, there is one I thought of.
Chairman Miller. Okay. Dr. Haseltine.
Dr. Haseltine. I would say Steve Amstrup who is our lead
polar bear biologist in Alaska and experiences conditions in
the Arctic out in the field every year.
Chairman Miller. Okay.
Dr. Haseltine. He certainly believes the climate is
changing.
Processes Leading to the Tipping Point
Chairman Miller. So it is two to nothing among Steves that
you can think of. Okay. But you all can think of other Steves
and get back to this on what the Steves you know, the
scientists named Steve, think. Dr. Alley, I understand that the
IPCC probably had some difficulty of kind of projecting exactly
what the processes were that would lead to the cascading
effect, the tipping point that you talked about. How well are
they accounted for, and particularly the ones we talked about
today, the melting of the permafrost, the release of carbon
dioxide and methane from the permafrost. How much was that
considered in the IPCC modeling?
Dr. Alley. It is not well included in the IPCC modeling. In
fact, there is a statement in regard to the sea level rise that
because of lack of inclusion of these carbon cycle feedbacks,
which is what you are referring to, and because of lack of
inclusion of understanding about the changes in the flow of the
ice sheets, that they can provide neither a best estimate nor
an upper limit on what sea level will do, and those were the
two uncertainties that were especially highlighted.
Chairman Miller. Anyone else? That seemed to be a question
for Dr. Alley or anyone else. Congratulations by the way on
winning the Nobel Prize.
Dr. Juday. Mr. Chairman, I think to squeeze the last bit of
uncertainty out of that question, we have one more piece of
information that we need, which is we need to poke holes in the
tundra and see if there is charcoal in them because the fact
that we are seeing fires now, and it is warmer now and that
makes it flammable doesn't quite rule out the possibility that
it happened before. It is not reported, it is not known,
everybody that I have spoken to who works in--charcoal, base of
the tundra? No, no, no. But we have to do that work in order to
be absolutely confident that this isn't already dialed into the
system that we have now.
Chairman Miller. Well, I will actually set an example and
not use the last 18 seconds of my time. Mr. Rohrabacher?
Mr. Rohrabacher. Thank you. I don't know if he ever signed
his name Steve but I certainly know numerous other scientists
who don't believe in the global warming that we are
experiencing today as human-caused. I also note there is a
scientist named Patrick Michaels who was the former Chairman of
the Committee of Applied Climatology of the American
Meteorological Society who suggests that all these reports of
the melting of all the ice on Greenland are totally
exaggerated. I have a quote here from----
Dr. Juday. Congressman, if I can just clarify what I
intended my response to be, all of the factors that can produce
warming or cooling happen all at the same time, and all I was
saying is that you have to account for all of them. It is a
good thing when you are trying to quantify one to isolate it
and see what strength its effect is, but then don't make the
mistake of going back and saying, oh, the others don't happen.
They all happen at the same time.
Polar Bear Population Changes in Canada
Mr. Rohrabacher. All I can suggest is there are a lot of
people who, a lot of very, very well-known scientists,
respected scientists throughout the world, people especially at
the senior levels who are--that they believe that their fellow
scientists have been influenced by the desire to get government
grants for funding and the fact that since Bill Clinton became
President of the United States, the bill all those years back,
that in order to get those grants you had to believe global
warming was caused by human beings. I have a statement here,
several here, of scientists, Dr. Mitch Taylor, a polar bear
biologist in the government there in Canada, and he is
suggesting that the polar bear population is not going down. In
fact, in 13 populations of polar bears in Canada, 11 are stable
or increasing in number, another quote suggesting the polar
bear numbers were actually underestimated in prior years and
thus now in fact are not seeing this decrease as it is being
suggested today. Are these two scientists just off or----
Dr. Haseltine. I could respond to that. I believe the 13
populations that you see quoted there are the 13 that at least
have some of their territory in Canada. That is the number in
Canada, and in the reassessment that we did over the last year,
five of those populations are declining, two of them are
depressed from over hunting, several of them are stable, I
don't remember the exact number, and none of them are
demonstrating to be increasing. So that is the----
Mr. Rohrabacher. So Dr. Taylor, the head of this department
there whose job it is to keep track of this, this isn't just a
side desk, this is what his job is, is wrong and you are right?
Dr. Haseltine. Well, I am quoting from the results of the
study in a recent article by----
Mr. Rohrabacher. Which is a study by the Geological Survey?
Dr. Haseltine. Right, and a recent article by Ian Sterling
who is one of the senior polar bear researchers for the
Canadian Wildlife Service. And so I think this individual who
works with Nunavut territories in Canada----
Mr. Rohrabacher. Okay, well----
Dr. Haseltine.--is using older information.
Naturally Occurring Climate Change
Mr. Rohrabacher. Well, let me put it this way. There are
experts who are not named Steve who are disagreeing with what
the findings are of the people here today. Let us just note
this that again, the central issue is whether or not all of
these things are caused by human activity or not. Just
coincidentally two nights ago the History Channel again ran,
with updates quite often, its long documentary on the mini-ice
age; and one of the facts I noticed there what they presented
which is again showing how 1,000 years ago it was a lot warmer
up in Greenland and Iceland and these places, a lot warmer than
it is today. And in fact, I don't know what the polar bear
population was at that time, and I am not sure that is not the
natural number of polar bears we should have in the world as
compared to now, but they did note that they said the volcanic
activity during the mini-ice age was about five times greater
than it has been over the last 150 years and that volcanic
activity which they then went into with their scientists on the
History Channel were indicating that volcanic activity actually
creates a situation where the Earth would be warmer without
that volcanic activity because it reflects the rays of the sun.
So here we have only one degree or maybe one and one-half
degrees warmer over the 150 years since the end of the mini-ice
age, and we have five times less the volcanic activity which
would tend to make it a warmer situation, not to mention
sunspots or whatever else; there is a natural explanation for
this as compared to the fact that we are driving in SUVs or we
have industrialization which of course can in no way explain
the warming that is also going on on Mars and Jupiter. So why
is it that we should be so concerned and try to regulate human
activity to save the polar bears when all of this may be just a
natural occurrence?
Chairman Miller. I was relieved to hear the word why,
suggesting that there was actually a question there. We are now
over the time, but you could respond briefly.
Dr. Juday. I was lead author of a chapter of Arctic climate
impact assessment in which we reviewed the evidence based on
tree ring studies that gives us essentially a complete record
from 8,000 years, and it shows the ups and downs of the
climate; and I would just refer you to that if you would like
to go through what has happened when, and I believe you can
download it at www.acia.uaf.edu. You have brought up several
different ideas there, and I just offer to talk to you to help
untangle some of them and distinguish between two things, the
empirical fact of what has happened and the interpretations of
why, the attribution.
Dr. Alley. Just to add, as you know, scientists float all
kinds of wonderful ideas and smart ones and crazy ones and we
bubble with ideas and then you help pay for activities that
seek to assess these and to give you sort of what stands
solidly and what is not solid, and those activities often come
out of the National Academy of Sciences, they come out of the
Intergovernmental Panel on Climate Change. Those groups have
assessed these. They have looked at the effect of volcanoes,
the effect of sun, the effect of other things and come to high
scientific confidence that in fact you see our footprint now in
what is going on. I would also like to add, and you were
quoting a scientist earlier, suggesting that perhaps we are
twirking our research to gain government grants and that we
might not be completely honest in what we are doing? Sir,
personally, I am under oath and I would never, ever, ever do
that and I do not believe any of my colleagues would do that.
Rest yourself absolutely assured that we are trying our hardest
and we are not lying to you, sir.
Mr. Rohrabacher. I will submit for the record at this point
then several quotations from very respected scientists making
that suggestion of others and who----
Dr. Alley. I am under oath.
Mr. Rohrabacher.--skewed research, et cetera, et cetera, in
order to get government grants. I will be happy to submit those
for the record.
[The information follows:]
Submitted for the Record
by Representative Dana Rohrabacher
QUOTES FROM EMINENT SCIENTISTS ON
SEVERAL GLOBAL WARMING ISSUES
Undue pressure and influence related to funding as well as political
peer pressure
William Gray
Bio
Dr. William M. Gray is a world famous hurricane expert and emeritus
Professor of Atmospheric Science, Colorado State University
Quote From an article in Discover, Vol. 26 no. 9, September 2005
``So many people have a vested interest in this global-warming thing--
all these big labs and research and stuff. The idea is to frighten the
public, to get money to study it more.''
See http://discovermagazine.com/2005/sep/discover-dialogue/
``Researchers pound the global warming drum because they know there is
politics, and money behind it.''
Richard Lindzen
Bio
Dr. Richard Lindzen is an atmospheric physicist, the Alfred P. Sloan
Professor of Meteorology at MIT and a member of the National Academy of
Science Lindzen is known for his research in dynamic meteorology--
especially atmospheric waves.
Quote From a Wall Street Journal op ed April 12, 2006; Page A14
``Alarm rather than genuine scientific curiosity, it appears, is
essential to maintaining funding. And only the most senior scientists
today can stand up against this alarmist gale, and defy the iron
triangle of climate scientists, advocates and policy-makers.''
See http://www.opinionjournal.com/extra/?id=110008220
Quote From Environment News, November 1, 2004 Publisher: The Heartland
Institute
``Global warming debate is more politics than science''
Dr. William Happer Jr.
Bio
Dr. Happer was named Eugene Higgins Professor of Physics and Chair of
the University Research Board and is a Fellow of the American Physical
Society, the American Association for the Advancement of Science, and a
member of the American Academy of Arts and Sciences, the National
Academy of Sciences and the American Philosophical Society.
Quote
When Director of Energy Research at the U.S. Department of Energy for
two years, Happer was asked to leave. ``I was told that science was not
going to intrude on policy.''
``With regard to global climate issues, we are experiencing politically
correct science. Many atmospheric scientists are afraid for their
funding, which is why they don't challenge Al Gore and his colleagues.
They have a pretty clear idea of what the answer they're supposed to
get is. The attitude in the administration is, `If you get a wrong
result, we don't want to hear about it.' ''
See http://www.sepp.org/Archive/controv/controversies/happer.html
Dr. Petr Chylek
Bio
Dr. Petr Chylek is a member of the technical staff at Space and Remote
Sensing Sciences, Los Alamos National Laboratory and an Adjunct
Professor of Physics and Atmospheric Science, Dalhousie University,
Halifax and New Mexico State University.
Quote
``Scientists who want to attract attention to themselves, who want to
attract great funding to themselves, have to (find a) way to scare the
public. . .and this you can achieve only by making things bigger and
more dangerous than they really are.''
See http://www.sepp.org/Archive/weekwas/2001/Aug25.htm
Dr. Bjorn Lomborg
Bio
Dr. Lomborg is adjunct professor at the Copenhagen Business School, and
author of the best-selling ``The Skeptical Environmentalist.'' He
organized the ``Copenhagen Consensus'' which brought together some of
the world's top economists.
Quote
``Its fear-mongering arguments have been sensationalized, which is
ultimately only likely to make the world worse off.''
See http://www.opinionjournal.com/extra/?id=110009182
Cost of Mitigatiion
Patrick Michaels
Bio
Dr. Patrick Michaels is a senior fellow at the Cato Institute and a
Research Professor of environmental sciences at the University of
Virginia. He is a Past President of the American Association of State
Climatologists and was Program Chair for the Committee on Applied
Climatology of the American Meteorological Society.
Quote from an article ``Live With Climate Change'' in USA Today on
February 2, 2007
``The stark reality is that if we really want to alter the warming
trajectory of the planet significantly, we have to cut emissions by an
extremely large amount, and--a truth that everyone must know--we simply
do not have the technology to do so. We would fritter away billions in
precious investment capital in a futile attempt to curtail warming''
See http://www.cato.org/
pub-display.php?pub-id=7502
Sea Level Change
Patrick Michaels
Bio
Dr. Patrick Michaels is a senior fellow at the Cato Institute and a
Research Professor of environmental sciences at the University of
Virginia. He is a Past President of the American Association of State
Climatologists and was Program Chair for the Committee on Applied
Climatology of the American Meteorological Society.
Quote from an article ``Global Warming: So What Else Is New?'' in the
San Francisco Chronicle on February 2nd, 2007.
``As measured recently by satellite, and published in Science magazine,
Greenland is losing .0004 percent of its ice per year, or 0.4 percent
per century. All modern computer models require nearly 1,000 years of
carbon concentrations three times what they are today to melt the
majority of Greenland's ice. Does anyone seriously believe we will be a
fossil-fuel powered society in, say, the year 2500?''
``A small but very vocal band of extremists have been hawking a
doomsday scenario, in which Greenland suddenly melts, raising sea
levels 12 feet or more by 2100.'' ``. . .it is repeated everywhere, and
its supporters are already claiming that the IPCC'' . . . ``is now
wrong because it has toned down its projections of doom and gloom.''
See www.cato.org/pubdisplay.php?pub-id=7543
Decline of Polar Bear Population
Dr. Mitchell Taylor
Bio
Dr. Mitchell Taylor, Polar Bear Biologist, Department of the
Environment, Government of Nunavut, Igloolik, Nunavut
Quote
``Of 13 populations of polar bears in Canada, 11 are stable or
increasing in number. They are not going extinct, or even appear to be
affected at present,''
See http://ff.org/centers/csspp/library/co2weekly/20060505/
20060505-17.html
IPCC Climate Models
Fred Singer
Bio
Dr Fred Singer is an atmospheric physicist and Professor Emeritus of
Environmental Sciences at the University of Virginia, adjunct scholar
at the National Center for Policy Analysis, and former Director of the
U.S. Weather Satellite Service.
Quote
``The models have erroneously predicted a 20th century surge in the
Earth's temperatures to match surging CO22 concentrations in
the atmosphere. It hasn't happened.''
See http://potpourriessays.blogspot.com/2007/06/global-warming.html
Richard Lindzen
Bio
Richard Lindzen is an atmospheric physicist, the Alfred P. Sloan
Professor of Meteorology at MIT and a member of the National Academy of
Science Lindzen is known for his research in dynamic meteorology--
especially atmospheric waves.
Quote from the Sunday Telegraph, October 30 2006
``As the primary ``consensus'' document, the Scientific Assessment of
the UN's Intergovernmental Panel on Climate Change notes, modelers at
the United Kingdom's Hadley Centre had to cancel two-thirds of the
model warming in order to simulate the observed warming.
``So the warming alarm is based on models that overestimate the
observed warming by a factor of three or more, and have to cancel most
of the warming in order to match observations.
``The temperature is as likely to go down as up.''
http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/10/29/
nclimate129.xml
Kevin Trenberth
Bio
Dr. Kevin E. Trenberth is Head of the Climate Analysis Section at the
National Center for Atmospheric Research. He has published over 400
scientific articles or papers, including 40 books or book chapters.
Quote
None of the models used by IPCC are initialized to the observed state
and none of the climate states in the models correspond even remotely
to the current observed climate. In particular, the state of the
oceans, sea ice, and soil moisture has no relationship to the observed
state at any recent time in any of the IPCC models.
See http://blogs.nature.com/climatefeedback/2007/06/
predictions-of-climate.html
Reducing Methane Emissions
Chairman Miller. Please do that, and Mr. Rohrabacher, you
have promised to provide that list on several occasions for the
record, and we have not gotten it at previous hearings, but we
will certainly be happy to take that.
It now appears that George Soros and ExxonMobil may be in a
desperate competition to identify a scientist named Steve whose
research they can fund. Ms. Siegel, it is true that you are not
a scientist on this panel. You are a lawyer, but it appears
that your testimony was the most hopeful of the testimony that
we have heard today. The three scientists were less hopeful or
their presentations were more grim than yours, but I do have a
couple questions about what we can be doing which is part of
your testimony as well. There is a landfill in my district.
There are landfills in everybody's district, but in this one,
it is being closed up, it is being covered over, and they are
still pulling off the methane and piping it a mile or two away
to a manufacturer who then uses that methane and burns it for
energy. What is it that governments and corporations and
individuals can be doing and are doing that would significantly
reduce methane?
Ms. Siegel. Thank you, Mr. Chairman. As you mentioned, we
have enormous opportunities to reduce methane from the waste,
the agriculture, and the energy sectors. One of the most
important things we can do in the waste sector is to divert
organic materials from landfills through composting, recycling,
and reuse programs. Where that is not feasible, methane can be
captured from the landfill gas and used to generate
electricity. The U.S. EPA estimates that 88 percent or 110
million metric tons could be abated this way in this country by
2010, and 10 percent or 12 million metric tons could be abated
at a cost benefit or no cost.
We can also capture methane from wastewater treatment
plants and use it to generate electricity. The biggest
opportunities are in the developing world where EPA estimates
there are approximately 600 million metric tons of
CO2, equivalent methane emissions reductions sitting
on the table. We don't have cost estimates for this, but it is
clear that expanding wastewater treatment facilities in the
developing world will have enormous public health benefits for
disease prevention and greatly reduce methane emissions.
In the energy sector, we also have enormous opportunities.
One of the primary sources of methane from natural gas systems
is through the leakage from lines and equipment, and there are
many, many different measures that fall into three categories
including operational changes, equipment upgrade and
replacement, and better inspection and maintenance; and over 50
percent of methane emissions, or 76 million metric tons, could
be abated this way with technology available today. 14.5
percent or 20 million metric tons could be done at a cost
benefit of up to $25 per metric ton from the natural gas
sector. Methane is also released from coal mining because
methane is produced when organic matter turns to coal and is
present in coal seams. We need an immediate moratorium on new
coal-fired power plants and to ultimately phase out existing
plants, and therefore coal mining as well; but nevertheless, it
is foolish to allow methane emissions to continue where coal
mining is still carried out for the time being. Nearly 50
percent or 25 million metric tons of baseline emissions could
be eliminated by the year 2010 in the U.S. at a cost benefit or
no cost. About 86 percent could be eliminated for less than $15
per ton.
Also, in the agricultural sector, we have very important
opportunities to capture methane from manure lagoons rather
than just letting the manure sit in the lagoons and emit the
methane using something called methane digesters. A digester is
a system of containers to collect and biologically treat manure
with naturally occurring microorganisms. The methane can then
also be used to generate electricity.
The EPA conservatively estimates that 11 million metric
tons of CO2 equivalent cost beneficial or no-cost
emissions could be abated this way from the agricultural
sector.
Action Items to Reduce Emissions
Chairman Miller. Thank you. One other question about along
the lines of action items, things that we can actually do. You
mentioned black carbon and the role that black carbon plays in
global warming. According to a recent NASA study, I assume it
was a NASA study and not a George Soros study, it could have
been by Dr. Hansen, black carbon which is really just
particulate matter or soot. I think you used the word soot
actually from industrial and biomass sources, is having a
significant warming impact in the Arctic because it reduces the
reflectivity of snow and ice. And according to NASA, about a
one-third of the black carbon in the arctic was actually coming
from South Asia and one-third from burning biomass or
vegetation around the world and one-third from North America,
Russian, and Europe. What can be done to reduce those sources
and is it happening? Is anyone doing it?
Ms. Siegel. The origin of black carbon that is deposited in
the Arctic is a very important area for further research, but
it is clear that the U.S. has a leadership role to play in this
regard. There are many, many things that can be done. For
example, we can replace diesel generators in the Arctic with
alternative energy sources, and where that is not possible
improve the efficiency and particulate controls on these
generators. We can replace coal and biomass burning in
residential stoves with alternative fuels or improve the
efficiency in particulate traps. Stringently regulating diesel
use in cars and trucks is very, very important and options
include upgrading vehicles, installing end-of-pipe filters,
better vehicle maintenance, and buyout/buyback programs for
super-emitters. We also need to not approve new coal-fired
power plants, phase out of existing coal-fired power plants by
increasing energy efficiency in the use of alternative energy,
and where coal-fired power plants must continue to operate for
now, implement more effective particulate controls. If we did
all these things we could start seeing progress by January
2009.
Chairman Miller. Thank you, Ms. Siegel. Mr. Rohrabacher.
Polar Bear Populations 1,000 Years Ago
Mr. Rohrabacher. Thank you very much. I am just surprised
that my staff had not submitted the quotes before, but we will
be submitting these quotes for the record. One of them I just
happen to have with me right now is from a Dr. William Grey who
is one of the world's most respected hurricane experts and
Emeritus Professor of Atmospheric Science at Colorado State
University who suggests that so many people have a vested
interest in this global warming thing, all these big labs and
research. The idea is to frighten the public to get money to
study it more. That is the end of that quote. And there are
about dozens of other quotes that we will put at least five or
six of them in the record. Dr. Grey is a respected person.
There are many, many respected scientists who are skeptical not
of the idea that the Earth is going through a warming trend but
that this has something to do with human activity. Again, the
show that I just happened to see on the History Channel, which
repeated and it is a wonderful documentary, went into great
detail about the sun and about volcanic activity and those
things that caused the temperature to change then. Let me ask
you this, 1,000 years ago before this mini-ice age, before this
trend that brought the temperatures down, which I might add,
all the studies that I have seen on global warming start at the
bottom of the mini-ice age after 500 years reduction of
temperature using that as the baseline, and you are one and
one-half degrees warmer than it was at the lowest point, as if
we should be concerned about that. Let us go back to that, the
1,000 before. How many polar bears were there 1,000 years ago
when the temperature was much different than it is today?
Dr. Haseltine. I don't think we know the number of polar
bears at that time. We do know that polar bears existed back
then.
Mr. Rohrabacher. If we say they can't exist if it is going
to be warmer now, we could assume there are fewer polar bears.
Now, is the number of polar bears 1,000 years ago what would be
the natural polar bear population or is it what it is now?
Dr. Haseltine. I don't believe there is a natural number of
polar bears. There will be a number of polar bears that their
habitat can support.
Climate Change Since the Last Ice Age
Mr. Rohrabacher. I think it is wonderful to see these
pictures of the skinny polar bear up there and tearing at our
hearts, those of us who love animals, and I do; and so you say,
then we have to do something which then gives us the right to
have the acceptance of our people to regulate their lives in
the name of saving that polar bear who now is thin as if we are
causing the polar bear to be thin. But in reality, 1,000 years
ago before any human activity had anything to do with
temperatures on the planet, even if you accept that 1,000 years
ago, the polar bear population was totally different. It was
warmer. Maybe you could tell me what was the ice cap like or
what was the level of ice in Greenland 1,000 years ago?
Dr. Alley. Our observations are not as good as we would
like, and we are working on that. The Climate Change Science
Program is going to do a report on that, and I am one of the
authors. So to be very clear, I cannot either prejudge or
presize what that report will say.
Mr. Rohrabacher. Well, what was Greenland like and what----
Dr. Alley. What we can say is that Greenland seems to have
responded to temperature. When it was warmer, it got smaller,
when it was colder it got bigger and that we are now pushing
toward temperatures that will pass those of the medieval warm,
that will pass those of the----
Mr. Rohrabacher. Well, no, no, we are one and one-half
degrees warmer now than it was 150 years ago and we have so
much less volcanic activity, et cetera. And it was how many
degrees warmer was it 1,000 years ago?
Dr. Alley. There are places--we do not have----
Mr. Rohrabacher. In Greenland and Iceland?
Dr. Alley. We do not have a reliable global--probably a
degree or two, something in that neighborhood.
Mr. Rohrabacher. What do the ice cores show us?
Dr. Alley. The ice cores show a very small signal that is
about one degree, one and one-half degrees or something in that
neighborhood in the summit of Greenland which is the one I
worked on----
Mr. Rohrabacher. How much----
Dr. Alley.--and that is based on my work.
Mr. Rohrabacher. How much warmer was it when they had all
these Vikings and everybody living in Greenland and Iceland and
they have all this agriculture going on? How much warmer was it
then? I think the History Channel put it at eight degrees to 10
degrees warmer.
Dr. Alley. That would seem very large to me. Ice core
records would indicate that we are back up to where we were if
not passing it.
Dr. Juday. Yeah, that is probably the case. I, by the way,
did a story, was interviewed, by a reporter from the Wall
Street Journal and--farmer in Greenland. So we are back to
about where we were 1,000 years ago. It is my suggestion if you
want to find that warmer period to use, I would suggesting the
hosing thermal maximum, the warmest it got since the end of the
last ice age, and that would be in the range of 6,000 to 8,000
years ago. It was warmer than it is now. It has been cooling
since----
Mr. Rohrabacher. All right, so 8,000 years ago there was a
period with almost no ice up there, and we think that today----
Dr. Juday. No, the tree line was further north. You can
find frozen remains of the trees almost to----
Mr. Rohrabacher. All right. So it was dramatically warmer
1,000 years ago and 8,000 years ago.
Dr. Juday. We are probably warmer now than 1,000 years ago.
We probably exceeded that.
Climate Change From Carbon Methane in the Permafrost
Chairman Miller. We are past time. We do have votes coming
up, so we do need to conclude the hearing. I just have one more
question for Dr. Alley. You said that the permafrost and frozen
peat, the possibility of release of carbon methane in the
permafrost and frozen peat was a big hole in the modeling by
the IPCC of how our climate could change and how our climate
could warm, but you didn't say how much. Do you have a sense of
how big the effect of that can be?
Dr. Alley. What it looks like based on simple models based
on what we know is that it doesn't--if we humans burn all of
our fossil fuel, the feedbacks from the permafrost do not
double what we did, but they are large enough that they
wouldn't matter to what we would do.
Chairman Miller. Large enough didn't matter?
Dr. Alley. Yeah, so we scientists like to say order of when
we are a little bit confused, so order of 10 to 30 percent sort
of feedbacks coming out of this, amplifying what we would do in
a burn it all.
Dr. Juday. If you could take all of the rapidly
decomposable carbon, because some of it is locked away in a
form, and it is just not going to come out, but so that is
killing everything and burning up everything, it would double--
it is equal to the atmospheric reservoir. So it would double
atmospheric CO2, so we are not going to do that,
even under the worst scenarios, but it does look like a
significant percentage of non-renewable percentage of it could
and probably has started to be mobilized.
Chairman Miller. Anyone else? Okay. I think that our
hearing is at a close. I want to thank all of you for
testifying today. There may be additional questions that could
be submitted in writing. You may think more about the scientist
you know named Steve and provide additional answers. And with
that, the witnesses are excused, and the hearing is now
adjourned.
[Whereupon, at 11:43 a.m., the Subcommittee was adjourned.]