The Great global warming update:

Allegre's second thoughts
The Deniers -- The National Post's series on scientists who buck the conventional wisdom on climate science

LAWRENCE SOLOMON, Financial Post
Published: Friday, March 02, 2007

Claude Allegre, one of France's leading socialists and among her most celebrated scientists, was among the first to sound the alarm about the dangers of global warming.

"By burning fossil fuels, man increased the concentration of carbon dioxide in the atmosphere which, for example, has raised the global mean temperature by half a degree in the last century," Dr. Allegre, a renowned geochemist, wrote 20 years ago in Cles pour la geologie.." Fifteen years ago, Dr. Allegre was among the 1500 prominent scientists who signed "World Scientists' Warning to Humanity," a highly publicized letter stressing that global warming's "potential risks are very great" and demanding a new caring ethic that recognizes the globe's fragility in order to stave off "spirals of environmental decline, poverty, and unrest, leading to social, economic and environmental collapse."

In the 1980s and early 1990s, when concern about global warming was in its infancy, little was known about the mechanics of how it could occur, or the consequences that could befall us. Since then, governments throughout the western world and bodies such as the United Nations Intergovernmental Panel on Climate Change have commissioned billions of dollars worth of research by thousands of scientists. With a wealth of data now in, Dr. Allegre has recanted his views. To his surprise, the many climate models and studies failed dismally in establishing a man-made cause of catastrophic global warming. Meanwhile, increasing evidence indicates that most of the warming comes of natural phenomena. Dr. Allegre now sees global warming as over-hyped and an environmental concern of second rank.

His break with what he now sees as environmental cant on climate change came in September, in an article entitled "The Snows of Kilimanjaro" in l' Express, the French weekly. His article cited evidence that Antarctica is gaining ice and that Kilimanjaro's retreating snow caps, among other global-warming concerns, come from natural causes. "The cause of this climate change is unknown," he states matter of factly. There is no basis for saying, as most do, that the "science is settled."

Dr. Allegre's skepticism is noteworthy in several respects. For one, he is an exalted member of France's political establishment, a friend of former Socialist president Lionel Jospin, and, from 1997 to 2000, his minister of education, research and technology, charged with improving the quality of government research through closer co-operation with France's educational institutions. For another, Dr. Allegre has the highest environmental credentials. The author of early environmental books, he fought successful battles to protect the ozone layer from CFCs and public health from lead pollution. His break with scientific dogma over global warming came at a personal cost: Colleagues in both the governmental and environmental spheres were aghast that he could publicly question the science behind climate change.

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