West of the Ice Continent, the last shelf of the Thwaites Glacier is increasingly cracking, according to new scientific observations. An event with dramatic consequences for coastal areas.
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Under the effect of global warming, alarming cracks threaten the “apocalypse glacier”. West of Antarctica, the Thwaites Glacier, 120 km wide, 600 km long and 3 km deep, is increasingly fragile, according to new observations made public * Monday, December 13. “The final collapse of the last ice shelf of the Thwaites Glacier [qui représente un tiers du glacier] could start by crossing cracks and hidden crevices in as fast as five years “, write the glaciologists.
Thanks to satellite data, underground radars and GPS measurements, they observed breaks in this pack ice which serves as the buttress of the glacier. “The ice shelf is kind of like a windshield, with a series of slowly opening cracks. You’re like, ‘I would have to change my windshield and someday, bang, there are million other cracks “, explains glaciologist Erin Pettit to Science *. The ice structure is also weakened by warmer seawater seeping below.
The fate of this distant piece of ice is crucial, especially for those living in coastal areas. The collapse of this platform will indeed accelerate the detachment of the glacier and its melting in the waters of the ocean. Thwaites is already contributing 4% of the 8 ” sea level rise seen today and this contribution could increase by a quarter with the demise of the last platform. If the glacier, threatened on the horizon of a few centuries, disappeared, the sea level would rise by 65 cm. Worse, all of West Antarctica, which contains enough ice to push the oceans up 3.3 meters, would then be threatened.
As three glaciologists explained to franceinfo in 2019, this catastrophic scenario is irreversible today because of global warming caused by our too carbon-intensive lifestyles (transport, food, housing). But there is still time to limit the damage. “If we manage to return to a period that is a little colder for example, it is quite conceivable that the glacier will continue to retreat but in a very, very slow manner”, explained in 2019 Eric Rignot, professor of Earth sciences at the University of California at Irvine. As long as we drastically reduce our greenhouse gas emissions.
* All links marked with an asterisk are in English.