A new glacier was born this week off the coast of Antarctica: A81, a huge block of ice with an area of 1,550 square kilometers (more than the surface of the Golan Heights), broke off from the Brant Ice Shelf during an exceptionally high spring tide. According to British Antarctic Survey (BAS) glaciologist Dominic Hodgson, its breakaway is “Part of the natural behavior of the Brant Ice Shelf”, and contrary to many reports is not related to climate change.
Satellite photographs recorded the moments of disconnection, on the Antarctic coast facing the South Pacific Ocean. The disconnection took place about a decade after the progress of a dormant crack in the ice, “Chasm-1” (Chasm-1) was detected. Two years ago a smaller glacier, A74, broke off from the same ice shelf. A chasm is a crack in the ice shelf that extends all the way from the surface to the ocean below. An ice shelf is a piece of floating ice that extends from glaciers formed on land.
Ted Scambos, a senior research scientist at the University of Colorado at Boulder, explains that the new glacier “is a huge mass of ice, about 500 billion tons,” but it is far from the largest glacier ever. An even more extensive glacier, A76, broke off in May 2021 from the Rhône-Filchner ice shelf, and before it broke it was considered the largest glacier ever, with an area of 4,320 square kilometers.
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The disconnection of A81, as it is now called according to the decision of the US National Ice Center, is not expected to affect the British Antarctic Survey’s Haley research station, which was moved offshore inland in 2016 as a precaution, after the crack in Abyss 1 began to grow However, “the new break places the base about 15 kilometers from the ocean, and new cracks may develop over the next few years, which will require another expensive move of the station,” Scambos says. The new glacier is expected to advance along a path similar to that of the A74 into the Weddell Sea.
Contrary to several glacier breakups and ice shelf collapses in recent years, which have been linked to climate change, a press release from the British Antarctic Survey stated that the breakup is part of a “natural process” and that “there is no evidence of a significant impact of climate change.” The chasm began to grow due to “tensions that accumulated due to the natural growth of the ice shelf”, said the glacier law from Northumbria University Hilmar Gudmundsson in an interview with the BBC in 2019.
Scambos describes the splitting of the glacier as a result of tremendous physical pressure. “The chisel was a small island, the MacDonald Ice Shelf,” Scambos says. “The ice was pushed against this rocky mountain by the force of the ice flow, and the rock forced it to split and eventually break off and break away from the floating ice shelf. These huge blocks of ice, sometimes the size of a small country, are spectacular. But they’re just part of how the Antarctic ice sheet works . In most cases, they have nothing to do with climate change.”