New data may affect political debate over global warming.
The Earth's polar regions long have been considered canaries in the coal mine on climate change - the first places to look, many scientists said, to learn whether the planet's temperature is, in fact, rising. Indeed, climate models generally predict that the heating of the atmosphere - precipitated by global warming - will cause the vast layer of ice that covers Antarctica to melt, raising sea levels and changing regional climate patterns by altering ocean currents.
This week, that widely held presumption is being challenged.
Two studies of temperatures and ice-cap movements in Antarctica suggest that the Southern Hemisphere's "canary" isn't going down without a fight - key sections of the ice cap appear to be growing thicker, not thinner, as previously believed. And the continent's average temperature appears to have cooled slightly during the past 35 years, not warmed.
Even as scientists work to make their climate models more accurate in the light of the new data, political opponents of the proposed Kyoto Protocol - which would limit human activity thought to cause atmospheric warming - are likely to pounce upon the results. The studies will likely be seen as vindication of their argument that the Kyoto treaty shouldn't be ratified until more is known about the science of climate change.
"This shows we really don't understand the climate dynamics of Antarctica," says Peter Dornan, an assistant professor at the University of Illinois at Chicago. It was Dornan's team of scientists whose research highlighted the temperature trend as part of a broader study of cooling's effect on the microscopic plant and animal life in the McMurdo Dry Valleys of Antarctica.