Published on January 2nd, 2017 | by James Ayre0
East Antarctica Ice Sheet More Vulnerable To Melting “Than Expected”
January 2nd, 2017 by James Ayre
Going on a mix of climate modeling, satellite observation, and on-site measurement, new research has indicated that East Antarctica’s ice sheet may be more vulnerable to melting “than expected.”
The recent work — the result of a team led by Jan Lenaerts of Utrecht University/KU Leuven and Stef Lhermitte of TU Delft/KU Leuven — argues that strong winds bringing warm air and blowing out snow make surrounding ice shelves more prone to melting than thought, and thus make the enormous East Antarctic ice sheet more prone to rapid melting than researchers have generally supposed.
Why does this matter?
“Tens of meters of rising sea levels are locked away in Antarctica,” notes Lenaerts. “And our research has shown that also East Antarctica is vulnerable to climate change.”
With melting of Antarctica’s ice sheets (the West Antarctic ice sheet is even more prone to melting than the East one) many of the world’s major cities and shipping ports will be swamped, and will eventually have to be abandoned. This will lead directly to the displacement of hundreds of millions of people, and thus to food insecurity, cultural disintegration and conflict, and war (whether the sort that we have been seeing in Syria, Somalia, etc., or the larger inter-state kind).
The press release provides more:
“However, to the researchers’ astonishment, the ice shelves in some regions of East Antarctica are melting faster than scientists had previously assumed. These ice shelves appear to be extremely sensitive to climate change. … This is because the strong and persistent wind transports warm, dry air to the region, and blows away the snow. This darkens the surface, which subsequently absorbs more of the sun’s heat. The result is a local warmer microclimate with a few literal ‘hotspots’. Because the ice shelf is floating in the ocean, its melting does not immediately contribute to sea level rise. However, the ice shelves around Antarctica are extremely important for ice sheet stability, because they hold back the land ice. If the ice shelves collapse, this land ice ends up in the ocean and consequently sea level will rise.”
Part of the new work was based around a “mysterious” crater that’s present on the King Baudoin ice shelf.
“In January 2016, the researchers visited the crater and discovered that it was a collapsed lake, with a moulin — a hole in the ice — which allowed the water to flow into the ocean. … Moreover, the researchers discovered that there were many meltwater lakes hidden under the surface of the ice, some of which were kilometres across. Underwater video images provide a clear image of the amount of meltwater present in the area.”
“That was a huge surprise. Moulins typically are observed on Greenland. And we definitely never see them on an ice shelf. … The crater isn’t new; we found it on satellite images from 1989. The amount of melt water differs immensely from year to year, but it clearly increases during warm years.”
Interesting times ahead. As a reminder, it’s worth keeping a close eye on what happens in the Arctic Ocean in 2017. With how strange the winter has been there so far, the year could hold some notable events.