Corrections Appended

Chicago

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.

In 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 1986 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.”