An example of a glacier calving in Antarctica (this particular one is on the Antarctic Peninsula.)
It’s been a dramatic end to the southern summer in Antarctica this month, at least as seen from space.
A massive heat wave over the southern polar region may have influenced three glacial calving events in East Antarctica in March, according to Helena Amanda Fricker, a glaciology professor at the Scripps Polar Center.
The largest of the three events was the complete collapse of the Conger Ice Shelf, which was as large as the area of New York City as recently as January. NASA satellite images captured the shelf disintegrated into large and small icebergs.
“Iceberg calving events are a natural part of the "checks and balances" of the Antarctic Ice Sheet, it has to shed the mass it gains through snowfall,” Fricker wrote on Twitter. “But since there was also an extreme warming event around this time, obviously we do need to examine if there is a link.”
On March 17, the US National Ice Center confirmed that an iceberg labeled C-38 had broken away from the shelf.
“C-38 comprised virtually all that remained of the Conger ice shelf,” USNIC said in a statement.
Sentinel-1A image of icebergs C-38 from March 17, 2022
The Conger Ice Shelf has been shrinking since at least 1973, but the melting and recession has accelerated dramatically in the past few years before its final demise.
“The concern is that floating ice shelves collapsing leads to acceleration of ice upstream,” tweeted University of Minnesota professor Peter Neff. “Floating ice shelves are like corks in a bottle; when they go, the upstream ice accelerates.”
This phenomenon was observed following the rapid collapse of the Larsen Ice Shelf in 2002. Accelerated glacial melt in Antarctica could intensify the process of sea level rise around the planet.
“We tend not to think of ice shelf collapse in East Antarctica,” Neff wrote. “Ice shelf collapse is a serious process no matter where in Antarctica... Effect should be small here, but highlights we can't sleep on East Antarctica.”