A new study, has found that, contrary to common belief, the East Antarctic Ice Sheet (EAIS) is vulnerable to rising planet temperatures and this could result in a dangerous rising of sea levels. The EAIS is the largest on the planet. If it were to fully melt, oceans could rise by 52 metres. Until now, although the rapid melting of West Antarctica was well documented, little was known about the EAIS, but I was thought that it was a fairly protected body of frozen freshwater.
The study, by Laura Herraiz-Borreguero and Alberto Garabato and published in Nature Climate Change, has looked at the ice sheet in more detail and has found that the surrounding water has warmed by 0.8 to 2.0 C in the 2010-2018 period as compared to the average from 1930-1990. As a result, there has been ice-mass loss and, although the scale is yet unknown, if global temperatures rise by more than 2.0 C, this could lead to instability in the EAIS and the rising of sea levels by many metres.
The rate at which the waters in the region have been warming has tripled since the 1990’s, particularly around East Antarctic continental slope, precisely where the ice sheet is losing more mass. The researchers have found that strong westerly winds have shifted in recent decades and now poleward, especially during the Summer. This changes currents and puts warmer waters in contact with the EAIS. Access to East Antarctica’s ice shelf is particularly difficult and this has resulted in insufficient reliable data to have a more profound understanding of the changes happening in the water system.
Herraiz-Borreguero, the study’s lead researcher, stated: “The consequences of warmer waters lapping the continental shelf would be severe. If warm water is able to penetrate the continental shelf and heat glacial ice, which currently sits on bedrock below sea level, “then the ice melt would be almost unstoppable.”