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Lamont, Okla: For decades, a small group of scientific
dissenters has been trying to shoot holes in the
prevailing science of climate change, offering one
reason after another why the outlook simply must be
wrong.
Over time, nearly every one of their arguments has
been knocked down and polls say 97 percent of working
climate scientists now see global warming as a serious
risk. Yet in recent years, the climate change skeptics
have seized on one last argument that cannot be so
readily dismissed. Their theory is that clouds will save
us.
They acknowledge that the human release of
greenhouse gases will cause the planet to warm. But they
assert that clouds — which can either warm or cool the
earth, depending on the type and location — will shift
in such a way as to counter much of the expected
temperature rise and preserve the equable climate on
which civilization depends.
“Clouds really are the biggest uncertainty,” said
Andrew E. Dessler, a climate researcher at Texas A&M.
“If you listen to the credible climate skeptics, they’ve
really pushed all their chips onto clouds.”
Richard S. Lindzen, a professor of meteorology at
the Massachusetts Institute of Technology, is the
leading proponent of the view that clouds will save the
day. His stature in the field — he has been making
seminal contributions to climate science since the 1960s
— has amplified his influence.
Dr. Lindzen says the earth is not especially
sensitive to greenhouse gases because clouds will react
to counter them, and he believes he has identified a
specific mechanism. On a warming planet, he says, less
coverage by high clouds in the tropics will allow more
heat to escape to space, countering the temperature
increase.
His idea has drawn withering criticism from other
scientists, who cite errors in his papers and say proof
is lacking. Enough evidence is already in hand, they
say, to rule out the powerful cooling effect from clouds
that would be needed to offset the increase of
greenhouse gases.
However, politicians looking for reasons not to
tackle climate change have embraced Dr. Lindzen, who has
obliged by assuring them that they are running no risks
by refusing to enact emission limits.
And with climate policy nearly paralyzed in the
United States, many other governments have also declined
to take action, and worldwide emissions of greenhouse
gases are soaring. |
