Scientists have long believed that while most of the rest of the globe has been getting steadily warmer, a large part of Antarctica -- the East Antarctic Ice Sheet -- has actually been getting colder. However, new research shows that for the last 50 years, much of Antarctica has been warming at a rate comparable to the rest of the world.
According to a paper documenting the warming to be published Thursday in Nature, the warming in West Antarctica is greater than the cooling in East Antarctica, meaning that on average the continent has gotten warmer.
"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, a University of Washington professor of earth and space sciences and lead author of the paper.
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 study found that warming in West Antarctica exceeded one-tenth of a degree Celsius per decade for the last 50 years and more than offset the cooling in East Antarctica.
(Xinhua News Agency January 22, 2009)