Antarctic Glacier Changes and Man-Made Global Warming
April 18, 2013; 3:10 PM
New ice core research from the University of Washington indicates that the accelerated rate of glacier thinning along the edge of Antarctica cannot be attributed with confidence to human-caused global warming.
Previous work by Eric Steig, a University of Washington professor of Earth and space sciences showed that rapid thinning of Antarctic glaciers was accompanied by rapid warming and changes in atmospheric circulation near the coast. His research with Qinghua Ding, a UW research associate, showed that the majority of Antarctic warming came during the 1990s in response to El Niño conditions in the tropical Pacific Ocean. (from the University of Washington News)
This new study now indicates that the 1990's were not greatly different from other warm decades such as the 1830's, 1940's and others.
Key excerpts from the University of Washington News report....
"If we could look back at this region of Antarctica in the 1940s and 1830s, we would find that the regional climate would look a lot like it does today, and I think we also would find the glaciers retreating much as they are today," said Steig, lead author of a paper on the findings published online April 14 in Nature Geoscience.
The most prominent of these in the last 200 years - the 1940s and the 1830s - were also periods of unusual El Niño activity like the 1990s. The implication, Steig said, is that rapid ice loss from Antarctica observed in the last few decades, particularly the '90s, "may not be all that unusual."
The same is not true for the Antarctic Peninsula, the part of the continent closer to South America, where rapid ice loss has been even more dramatic and where the changes are almost certainly a result of human-caused warming, Steig said.