The effects of global climate cycles on Southern Ocean temperatures drove cycles of melting and freezing in the East Antarctic Ice Sheet every few thousand years, according to a new study.
By analyzing unusual rock samples collected years ago in Antarctica, scientists at the University of California, Santa Cruz, have discovered a remarkable record of how the East Antarctic Ice Sheet has responded to changes in climate over a period of 100,000 years during the Late Pleistocene.
The East Antarctic Ice Sheet is the world’s largest ice mass. Understanding its sensitivity to climate change is crucial for efforts to project how much sea level will rise as global temperatures increase. Recent studies suggest it may be more vulnerable to ice loss than previously thought.
The new study, published September 15 in Nature Communications, provides evidence of changes at the base of the ice sheet over a broad area in response to cyclic changes in climate during the Pleistocene. The changes are reflected in the types of minerals deposited at the base of the ice sheet.
Read more at University of California, Santa Cruz
Image: UCSC researchers analyzed two rock samples collected in Eastern Antarctica in which alternating layers of calcite and opal reflect cyclic changes in the subglacial environment. Sample MA113 is 9 centimeters thick and comes from Mount Achernar Moraine on the side of Law Glacier. (Credit: Gavin Piccione)