The Copenhagen Diagnosis: Sobering Update on the Science
On the eve of the Copenhagen conference, a group of
scientists has issued an update on the 2007 report of the
Intergovernmental Panel on Climate Change. Their conclusions? Ice
at both poles is melting faster than predicted, the claims of
recent global cooling are wrong, and world leaders must act fast if
steep temperature rises are to be avoided.
by elizabeth kolbert
Yale 360 - Ahead of talks in
Copenhagen, a group of leading climate scientists has issued a new
report summarizing the most recent research findings from around
the world and concluding that scientists have underestimated the
pace and extent of global warming. The report - titled “
Copenhagen Diagnosis” - finds that in several key areas
observed changes are outstripping
target=”_blank”>the most recent projections by the UN’s
Intergovernmental Panel on Climate Change and warns that “there is
a very high probability of the warming exceeding 2 °C unless global
emissions peak and start to decline rapidly” within the next
decade.
The report points to dramatic declines in Arctic sea ice, recent
measurements that show a large net loss of ice from both Greenland
and Antarctica, and the relatively rapid rise in global sea levels
- 3.4 millimeters per year - as particular reasons for concern.
Sea-level rise this century, it states, “is likely to be at least
twice as large” as predicted by the most recent IPCC report, issued
in 2007, with an upper limit of roughly two meters.
“Sea level is rising much faster and Arctic sea ice cover shrinking
more rapidly than we previously expected,” Stefan Rahmstorf,
department head at Germany’s Potsdam Institute for Climate Impact
Research, said in a press release accompanying the report.
“Unfortunately, the data now show us that we have underestimated
the climate crisis in the past.”
Several elements of the climate system could reach a
‘tipping point’ in coming decades.
According to the report, which was released today, there are
several elements of the climate system that could reach a
“tipping point” in coming decades if current emissions trends
continue. The report notes that even at current greenhouse gas
concentrations, it is already “very likely” that a “summer ice-free
Arctic is inevitable.” The Greenland Ice sheet, too, the report
warns, “may be nearing a tipping point where it is committed to
shrink.”
The report’s 26 authors include scientists from Germany, France,
Switzerland, Austria, Canada, the U.S., and Australia. Most were
also authors of the last IPCC report, and donated their time to
draft “The Copenhagen Diagnosis.” The University of New South
Wales’ Climate Change Research Centre provided logistical
support.
“We thought that the IPCC report from 2007 was a superb report, but
of course science doesn’t stand still,”
target=”_blank”>Richard Somerville, a climate modeler and
professor emeritus as the Scripps Institution of Oceanography,
said. “And we thought it would be helpful if we could provide some
kind of updated assessment.”
In an e-mail message from Antarctica, where he is doing fieldwork,
target=”_blank”>Robert Bindschadler, of NASA, said the group
had been prompted to write the report by “the rapidity and serious
consequences of climate change.”
Georg Kaser, a glaciologist at the University of Innsbruck, said he
hoped policymakers would respond to the report by deciding to
“totally phase out fossil-fuel burning within the next two
decades.”
“Dreaming is allowed,” he added. “Frankly speaking, I would not
like to be a policymaker that has just two options: one, phasing
out fossil fuel burning immediately, or two, committing our society
to major and long-lasting changes in the climate system.”
The report states that ‘global cooling’ has not
occurred over the past decade.
The report was already completed but not released by the time
world leaders, including President Obama, announced in Singapore on
Nov. 15 that they had abandoned the goal of reaching a legally
binding agreement in Copenhagen. Since then, several countries have
announced commitments to reduce their greenhouse gas emissions,
including South Korea, which last week pledged to a cut of 20
percent below “business as usual” by 2020, and Brazil, which
promised reductions of 40 percent below current projections by
2030. But the United States, with some of the highest per capita
emissions in the world and the second-highest overall emissions,
after China, has made no commitment, and legislation to curb
emissions, which narrowly passed the House this year, is not
expected to be taken up by the U.S. Senate until after the
Copenhagen session is over.
Andrew Weaver, a climate modeler at Canada’s University of Victoria
and one of the authors of “The Copenhagen Diagnosis,” said he found
the announcement that world leaders were
target=”_blank”>abandoning the goal of reaching a binding agreement
this year “unacceptable.”
He went on: “Maybe they should be honest, and stand up and say,
‘You know what? As your political leaders we do not accept that we
owe anything to future generations.’ I don’t think they’d ever say
that, but this is what they are saying if they don’t deal with this
problem.”
“The Copenhagen Diagnosis” is not the first report to warn that
climate change is occurring even more rapidly than had been
predicted by the IPCC. Indeed, the UN itself has made this point.
In September, the United Nations Environment Program released its
“Climate Change Science Compendium 2009.” In the foreword of that
report, UN Secretary General Ban Ki-moon noted that “climate change
is accelerating at a much faster pace than was previously thought
by scientists.” He warned: “Unless we act, we will see catastrophic
consequences including rising sea levels, droughts and famine, and
the loss of up to a third of the world’s plant and animal
species.”
‘We see changes that we did not anticipate two or
three years ago.’
“The Copenhagen Diagnosis” is explicitly aimed at
“policy-makers, stakeholders, the media and the broader public”
target=”_blank”>on the eve of the international climate talks
that begin on Dec. 7. It takes up several questions of the sort not
typically addressed in scientific forums, but frequently raised on
the Internet and in the press. One of these is whether the Earth’s
atmosphere is already saturated with carbon dioxide.
The answer to this question, the report says, is “Not even
remotely. It isn’t even saturated on the runaway greenhouse planet
Venus, with its atmosphere made up of 96% CO2 and a surface
temperature of 467 °C.” Similarly, the report states, “global
cooling” has not occurred over the past decade, “contrary to claims
promoted by lobby groups and picked up in some media.” In fact,
“even the highly ‘cherry-picked’ 11-year period starting with the
warm 1998 and ending with the cold 2008 still shows a warming trend
of 0.11 °C per decade,” the report concludes.
The report notes that in recent years, solar output has been at a
low ebb. Meanwhile, warming has continued: “It is perhaps
noteworthy that despite the extremely low brightness of the sun
over the past three years temperature records have been broken
during this time… The years 2007, 2008 and 2009 had the lowest
summer Arctic sea ice cover ever recorded, and in 2008 for the
first time in living memory the Northwest Passage and the Northeast
Passage were simultaneously ice-free. This feat was repeated in
2009. Every single year of this century (2001-2008) has been among
the top ten warmest years since instrumental records began.”
As Effects of Warming Grow, UN Report is Quickly
Dated
The 2007 report from the Intergovernmental Panel on Climate Change
was a voluminous and impressive document. Yet key portions of the
report are already out of date, as evidence shows the impacts of
warming intensifying from the Arctic to Antarctica.
Coming to Copenhagen: Prospects for Success?
With prospects waning that a binding accord on
reducing greenhouse gas emissions can be reached at the climate
talks in Copenhagen next month, ten environmental leaders and
climate experts outline for Yale Environment 360 what they
believe can still be accomplished.Konrad Steffen, a glaciologist at
the University of Colorado who recently returned from taking
measurements on Antarctica, said, “We as scientists wanted to make
sure we provided all possible information. We tried to stay away
from judgment calls - you wouldn’t believe the lengthy emails that
we had - but on the other hand we wanted to make sure the urgency
is there. We want to tell people it is urgent. We see changes that
we did not anticipate two or three years ago.”Gavin Schmidt,
a NASA climate scientist who was not involved in “The Copenhagen
Diagnosis,” said he thought the report was scientifically sound,
but questioned whether it would have much impact on its target
audience. “Knowing exactly how fast emissions are rising, or sea
ice is melting, is useful and interesting, but my guess is that it
will not have much effect on the delegates, since it doesn’t
address the actual equity and political issues that are at the
heart of the slow movement towards an agreement,” said
Schmidt.
Richard Somerville, of Scripps, acknowledged that scientific
information - up-to-the minute or otherwise - was often ignored at
climate negotiations.
“I’ve been to several of these meetings,” he said. “The delegates
and the leaders say very kind things about the IPCC and thank it
for its excellent work. But then, from a scientist’s point of view,
once the negotiations start they might as well be negotiating, say,
steel tariffs. I’ve actually heard politicians say - I won’t name
any names - ‘We don’t want to be constrained by the science.’” But,
he added, that only makes it more essential to get the information
out.
“Not politicians and not money and not public opinion, but the
climate system itself imposes a time scale,” Somerville said. “And
if the world chooses not to stick within that, well, Mother Nature
bats last.”
Source: www.e360.yale.edu
