Oddly enough, most of the news coverage neglected to mention that the document released on Feb. 2 by the UN's Intergovernmental Panel on Climate Change was not the latest multiyear assessment report, which will run to something like 1,500 pages when it is released in May. It was only the 21-page "Summary for Policymakers," a document written chiefly by government bureaucrats -- not scientists -- and intended to shape public opinion. Perhaps the summary will turn out to be a faithful reflection of the scientists' conclusions, but it wouldn't be the first time if it doesn't.
In years past, scientists contributing to IPCC assessment reports have protested that the policymakers' summary distorted their findings -- for example, by presenting as unambiguous what were actually only tentative conclusions about human involvement in global warming. This time around, the summary is even more confident: It declares it "unequivocal" that the Earth has warmed over the past century and "very likely" -- meaning more than 90 percent certain -- that human activity is the cause.
That climate change is taking place no one doubts; the Earth's climate is always in flux. But is it really so clear-cut that the current warming, which amounts to less than 1 degree Celsius over the past century, is anthropogenic? Or that continued warming will lead to the meteorological chaos and massive deaths that alarmists predict? It is to the media. By and large they relay only the apocalyptic view: Either we embark on a radical program to slash carbon-dioxide emissions -- that is, to arrest economic growth -- or we are doomed, as NBC's Matt Lauer put it last week, to "what literally could be the end of the world as we know it."
Perhaps the Chicken Littles are right and the sky really is falling, but that opinion is hardly unanimous. There are quite a few skeptical scientists, including eminent climatologists, who doubt the end-of-the-world scenario. Why don't journalists spend more time covering all sides of the debate instead of just parroting the scaremongers?
Only rarely do other views pierce the media's filter of environmental correctness. A recent series by Lawrence Solomon in Canada's National Post looked at some of the leading global-warming dissenters, none of whom fits the easy-to-dismiss stereotype of a flat-Earth yahoo. There is, for example, Richard S.J. Tol -- IPCC author, editor of Energy Economics, and board member of the Centre for Marine and Climate Research at Hamburg University. Tol agrees that global warming is real, but he emphasizes its benefits as well as its harms -- and points out that in the short term, the benefits are especially pronounced.
"Tol is a student of human innovation and adaptation," writes Solomon. "As a native of the Netherlands, he is intimately familiar with dikes and other low-cost adaptive technologies, and the ability of humans in meeting challenges in their environment." Whatever changes global warming may bring, Tol is confident that human beings will adjust to them with ingenuity and resourcefulness.
Another dissident is Duncan Wingham, professor of climate physics at University College London and principal scientist of the European Space Agency's CryoSat Mission, which is designed to measure changes in the Earth's ice masses. The collapse of ice shelves off the northern Antarctic Peninsula is often highlighted as Exhibit A of global warming and its dangers, but Wingham's satellite data shows that the thinning of some Antarctic ice has been matched by thickening ice elsewhere on the continent. The evidence to date, Wingham says, is not "favorable to the notion we are seeing the results of global warming."
Still other scientists profiled by Solomon contend that the sun, not man, plays the dominant role in planetary climate change.
Henrik Svensmark of the Danish National Space Center, for instance, believes that changes in the sun's magnetic field, and the corresponding impact on cosmic rays, may be the key to global warming. Nigel Weiss, a past president of the Royal Astronomical Society and a mathematical aerophysicist at the University of Cambridge, correlates sunspot activity with changes in the Earth's climate. Habibullo Abdussamatov, who heads the space research laboratory at Pulkovo Astronomical Observatory in Russia, points out that Mars is also undergoing global warming -- despite having no greenhouse conditions and no activity by Martians. In his view, it is solar irradiance, not carbon dioxide, that accounts for the recent rise in temperature.
Climate-change hyperbole makes for dramatic headlines, but the real story is both more complex and more interesting. Chicken Little may claim the sky is falling. A journalist's job is to check it out.
(Jeff Jacoby is a columnist for The Boston Globe.)