Is Ice Loss by Glaciers Abnormal?
In the last few decades, glaciers at the edge of the icy continent of Antarctica have been thinning, and research has shown the rate of thinning has accelerated and contributed significantly to sea level rise. New ice core research suggests that, while the changes are dramatic, they cannot be attributed with confidence to human-caused global warming, said Eric Steig, a University of Washington professor of Earth and space sciences. Previous work by Steig has shown 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 Niņo conditions in the tropical Pacific Ocean. Their new research suggests the '90s were not greatly different from
some other decades -- such as the 1830s and 1940s -- that also showed
marked temperature spikes. The researchers' results are based on their analysis of a new ice core from the West Antarctic Ice Sheet Divide that goes back 2,000 years, along with a number of other ice core records going back about 200 years. They found that during that time there were several decades that exhibited similar climate patterns as the 1990s. Antarctica mountain image via Shutterstock. Read more at Science Daily.
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