Cold, Hard Facts
IN the debate on global warming, the data on the climate of Antarctica
has been distorted, at different times, by both sides. As a polar
researcher caught in the middle, I’d like to set the record straight.
n January 2002, a research paper about Antarctic temperatures, of
which I was the lead author, appeared in the journal Nature. At the
time, the Antarctic Peninsula was warming, and many people assumed that
meant the climate on the entire continent was heating up, as the Arctic
was. But the Antarctic Peninsula represents only about 15 percent of
the continent’s land mass, so it could not tell the whole story of
Antarctic climate. Our paper made the continental picture more clear.
My
research colleagues and I found that from 1996 to 2000, one small,
ice-free area of the Antarctic mainland had actually cooled. Our report
also analyzed temperatures for the mainland in such a way as to remove
the influence of the peninsula warming and found that, from 1966 to
2000, more of the continent had cooled than had warmed. Our summary
statement pointed out how the cooling trend posed challenges to models
of Antarctic climate and ecosystem change.
Newspaper and
television reports focused on this part of the paper. And many news and
opinion writers linked our study with another bit of polar research
published that month, in Science, showing that part of Antarctica’s ice
sheet had been thickening — and erroneously concluded that the earth
was not warming at all. “Scientific findings run counter to theory of
global warming,” said a headline on an editorial in The San Diego
Union-Tribune. One conservative commentator wrote, “It’s ironic that
two studies suggesting that a new Ice Age may be under way may end the
global warming debate.”
In a rebuttal in The Providence Journal,
in Rhode Island, the lead author of the Science paper and I explained
that our studies offered no evidence that the earth was cooling. But
the misinterpretation had already become legend, and in the four and
half years since, it has only grown.
Our results have been
misused as “evidence” against global warming by Michael Crichton in his
novel “State of Fear” and by Ann Coulter in her latest book, “Godless:
The Church of Liberalism.” Search my name on the Web, and you will find
pages of links to everything from climate discussion groups to Senate
policy committee documents — all citing my 2002 study as reason to
doubt that the earth is warming. One recent Web column even put words
in my mouth. I have never said that “the unexpected colder climate in
Antarctica may possibly be signaling a lessening of the current global
warming cycle.” I have never thought such a thing either.
Our
study did find that 58 percent of Antarctica cooled from 1966 to 2000.
But during that period, the rest of the continent was warming. And
climate models created since our paper was published have suggested a
link between the lack of significant warming in Antarctica and the
ozone hole over that continent. These models, conspicuously missing
from the warming-skeptic literature, suggest that as the ozone hole
heals — thanks to worldwide bans on ozone-destroying chemicals — all of
Antarctica is likely to warm with the rest of the planet. An
inconvenient truth?
Also missing from the skeptics’ arguments is
the debate over our conclusions. Another group of researchers who took
a different approach found no clear cooling trend in Antarctica. We
still stand by our results for the period we analyzed, but unbiased
reporting would acknowledge differences of scientific opinion.
The
disappointing thing is that we are even debating the direction of
climate change on this globally important continent. And it may not end
until we have more weather stations on Antarctica and longer-term data
that demonstrate a clear trend.
In the meantime, I would like to
remove my name from the list of scientists who dispute global warming.
I know my coauthors would as well.
Peter Doran is an associate professor of earth and environmental sciences at the University of Illinois at Chicago.
Credits to http://nytimes.com/2006/07/27/opinion/27doran.html
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