For the first time in human history, an ice shelf in East Antarctica has collapsed, scientists said Friday, as climate change shows no signs of slowing.
The collapse of the 460 square miles wide (1200 square kilometers) Glenzer-Conger ice shelf, which occurred last week, came as temperatures rose in the eastern section of Antarctica by as much as 70 degrees Fahrenheit above normal.
The ice shelf has been holding in the Conger and Glenzer glaciers from the warmer water. It collapsed between March 14 and 16, said ice scientist Catherine Walker of the Woods Hole Oceanographic Institute, reports the Associated Press.
NASA satellites first detected the collapse of the ice shelf. Satellite photos show the area had been shrinking rapidly the last couple of years, and now scientists wonder if they have been overestimating East Antarctica’s stability and resistance to global warming that has been melting ice rapidly on the smaller western side and the vulnerable peninsula.
“The Glenzer Conger ice shelf presumably had been there for thousands of years and it’s not ever going to be there again,” said University of Minnesota ice scientist Peter Neff.
“We still treat East Antarctica like this massive, high, dry, cold and immovable ice cube,” Neff said, reports The Guardian. “Current understanding largely suggests you can’t get the same rapid rates of ice loss [as in West Antarctica] due to the geometry of the ice and bedrock there.”
Satellite data from the Copernicus Sentinel-1 mission showed that movement of the ice shelf began between 5 and 7 March, Neff said.
Keeping an eye on Eastern Antarctica
The issue isn’t the amount of ice lost in this collapse, Neff and Walker said. That is negligible. It’s more about “where it happened.” And Neff worries that previous assumptions about East Antarctica’s stability may not be correct.
This worry is important because if the frozen water in East Antarctica melted — and that’s a millennia-long process if not longer — it would raise seas across the globe more than 160 feet (50 meters). It’s more than five times the ice in the more vulnerable West Antarctic Ice Sheet, where scientists have concentrated much of their research.
However, British Antarctic Survey geophysicist Rob Larter says, “Most of East Antarctica is relatively secure, relatively invulnerable and there are sectors in it that are vulnerable.”
“The overall effect of climate change around East Antarctica is it’s chipping away at the edges of the ice sheets in some places, but it’s actually adding more snow to the middle,” he added.
Benjamin Strauss, the president and CEO of Climate Central, a nonprofit that tries to educate policymakers and the public about the threats posed by climate change, told Yahoo News, “The same thing is true for the big ice sheets on Greenland and Antarctica and glaciers around the world. We turned up the thermostat. We’ve already heated the planet by a couple of degrees, but they’ve only begun to respond by melting. And that’s why we have all this extra sea level in the pipeline.
