By IANS,
Washington : Much of Antarctica has been warming, not getting any colder, as suspected by scientists studying climate change.
The study found that warming in West Antarctica exceeded a tenth of a degree Celsius per decade for the last 50 years and more than offset the cooling in East Antarctica.
“West Antarctica is a very different place than East Antarctica, and there is a physical barrier, the Transantarctic Mountains, that separates the two,” said Eric Steig, co-author of the study and professor, University of Washington (UW).
For years it was believed that a relatively small area known as the Antarctic Peninsula was getting warmer, but that the rest of the continent – including West Antarctica, the ice sheet most susceptible to potential future collapse – was cooling.
Steig noted that the West Antarctic Ice Sheet, with an average elevation of about 6,000 feet above sea level, is substantially lower than East Antarctica, which has an average elevation of more than 10,000 feet.
While the entire continent is essentially a desert, West Antarctica is subject to relatively warm, moist storms and receives much greater snowfall than East Antarctica.
The researchers devised a statistical technique that uses data from satellites and from Antarctic weather stations to make a new estimate of temperature trends.
“People were calculating with their heads instead of actually doing the math,” Steig said. “What we did is interpolate carefully instead of just using the back of an envelope.
“While other interpolations had been done previously, no one had really taken advantage of the satellite data, which provide crucial information about spatial patterns of temperature change,” he said.
Satellites calculate the surface temperature by measuring the intensity of infrared light radiated by the snow pack, and they have the advantage of covering the entire continent. However, they have only been in operation for 25 years, said an University of California-Berkeley release.
The study was published in the Thursday edition of Nature.