Melting of Antarctica's 'Doomsday Glacier' could raise sea levels by 10ft, scientists say

Melting of Antarctica’s ‘Doomsday Glacier’ could raise sea levels by 10ft, scientists say

One of Antarctica’s largest glaciers is holding ‘by its fingernails’ as warming temperatures around the world threaten to cause further deterioration, which could then destabilize glaciers across the region.

Thwaites Glacier, located in the Amundsen Sea in West Antarctica, is among the fastest growing glaciers in the region, scientists say. Together with Pine Island, also located in the Amundsen Sea, the two structures are responsible for the greatest contribution to sea level rise in Antarctica.

Now scientists are discovering that the Thwaites Glacier, also known as the ‘Glacier of the Apocalypse’, is melting faster than previously thought as warm, dense deep water provides heat to the cavity current pack ice and melting its ice shelves from below, according to a study published Monday in Nature Geoscience.

Thwaites, roughly the size of Florida, is known for his quick retirement. But researchers from the College of Marine Science at the University of South Florida and the British Antarctic Survey have mapped a critical area of ​​the seafloor ahead of the glacier that could contribute to faster melting in the future.

PHOTO: Thwaites Glacier in West Antarctica.

Thwaites Glacier in West Antarctica.

James Youngel/NASA

Satellite images released in 2020 of the Pine Island and Thwaites glaciers, which sit next to each other, showed heavily crevassed areas and open fractures – two signs that shear zones on the two glaciers, where the ice shelf is thin, had weakened structurally over the past decade.

But scientists have now found that the Thwaites Glacier grounding zone is retreating closer to more than 2.1 kilometers per year, double the rate observed by satellite imagery in the fastest part of the grounding. between 2011 and 2019, according to the study.

Researchers have documented more than 160 parallel ridges that were created as a result of the glacier’s leading edge retreating and moving up and down with daily tides. Additionally, the scientists analyzed submerged rib-like formations about half a mile below the ocean, determining that each new rib likely formed in a single day.

Large calving events, when a large chunk breaks off, occurred on Thwaites in October 2018 and February 2020, when an unprecedented sea ice retreat occurred. The feedback process, likely triggered by further damage to the ice shelf, resulted in the preconditioning of ice shelves for further decay and large calving events.

PHOTO: An aerial view of the Thwaites Glacier in West Antarctica, January 30, 2019.

An aerial view of the Thwaites Glacier in West Antarctica, January 30, 2019.

Jeremy Harbeck/OIB/NASA

This makes the Thwaites and Pine Island Ice Shelves more susceptible to extreme weather changes in the ocean, atmosphere and sea ice. If Thwaites and Pine Island were to destabilize, several of the nearby areas would also collapse, causing widespread collapse, the scientists said. Thwaites alone could raise sea levels by around 10 feet, the scientists said.

In December, researchers at the University of Colorado at Boulder predicted that Thwaites would only last a few years before collapsing.

“Thwaites is really hanging on to his nails today, and we should expect to see big changes on small time scales in the future – even from year to year – once the glacier settles. will retreat past a shallow ridge in its bed,” Robert Larter said. , British Antarctic Survey marine geophysicist and co-author of the study, in a statement.

Researchers from the United States, United Kingdom and Sweden used a state-of-the-art robotic vehicle loaded with imaging sensors, dubbed “Ran”, to collect the images and supporting geophysical data, described by Anna Wahlin, physical oceanographer at the University. of Gothenburg, as “a pioneering study of the ocean floor”.

“The images Ran collected give us vital information about the processes taking place today at the critical junction between the glacier and the ocean,” Wahlin said.

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