Antarctica: an expanse of ice floe as big as twelve times Paris collapses


Global warming

Called “Conger,” this ice shelf collapsed in mid-March as temperatures at the South Pole hit record highs. This melting is one of the most significant events in Antarctica for 20 years.

One thousand two hundred square kilometers, or twelve times the size of the city of Paris, reduced to crumbs in a few days. Scientists reveal this Friday, based on satellite data, that a huge expanse of sea ice collapsed in eastern Antarctica around mid-March, as reported by the Guardian. Called “Conger”, this ice shelf had been shrinking since the mid-2000s, but in recent months the melting has apparently accelerated.

The record temperatures, measured last week in Antarctica, do not seem to be a coincidence. On March 18, the Concordia station, located more than 3,000 meters above sea level, showed -11.8 ° C. That is more than 40 degrees above normal for the season. From “never seen in Antarctica” according to several scientists.

March was, moreover, according to the professor of glaciology at the Scripps Polar Center Helen Amanda Fricker, a month particularly favorable to ice floes collapses: at least three major calvings – detachment of a piece of ice from a glacier – have been recorded in East Antarctica.

“The sign of what could happen in the future”

According to Catherine Colello Walker, a scientist at NASA and the Woods Hole Institute of Oceanography interviewed by the Guardian, the collapse of Conger remains “one of the most significant in Antarctica since the early 2000s”. However, she assures us that this is not likely to have significant effects, “but that it is a sign of what could happen in the future”.

The collapse of part of the pack ice is not in itself dangerous for the rise in the global level of the oceans, since it is only an expanse of ice which rests on the sea. But its detachment can greatly accelerate the melting of a much larger glacier, which could have dramatic consequences.

The climatologist specializing in glaciology at the University of Grenoble-Alpes-CNRS, Catherine Ritz, explained this phenomenon in Freed in 2021: “Here’s how it works: the glacier sits on land, and when it gets to the water’s edge, it develops a frozen floating tongue. If it leaves, it’s like removing a plug and the melting of the rest of the glacier is accelerating.

Fears point to West Antarctica

Conger’s rupture should not have any particular consequences because, as Professor Matt King, who heads the Australian Center of Excellence in Antarctic Sciences, notes in the Guardian, it fortunately only protected a small glacier. But otherwise, it could have “seriously raise sea levels”. A scenario that may occur in the future, assures Matt King: “Given global warming, we will see more and more ice shelves breaking up.”

The glaciers that most concern scientists in Antarctica are found in the west. The enormous Thwaites glacier, the size of the United Kingdom, is particularly scrutinized very closely. Nicknamed the “glacier of the apocalypse”, it would contain enough water to raise the oceans by more than two meters. A study, published by Oregon State University in the United States in 2021, estimates that a large part could come off in the next five years, which could cause a chain reaction and a point of no comeback.





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