Comment A large Antarctic glacier that could raise sea levels several feet is melting faster than predicted, according to a new study published Monday in the journal Nature Geoscience. Thwaites Glacier — dubbed the “glacier of doom” because scientists estimate that without it and its supporting ice shelves, sea levels could rise more than 3 to 10 feet — is located in the western part of the continent. After recently mapping it in high resolution, an international team of researchers found that the ice sheet experienced a phase of “rapid retreat” sometime in the past two centuries – lasting less than six months. According to a press release accompanying the study, the researchers concluded that the glacier “lost contact with a seabed ridge” and is now retreating at a rate of 1.3 miles per year — double the rate they predicted between 2011 and 2019 . Unlike some other land-bound glaciers, Thwaites is grounded to the seabed, making it more vulnerable to warming waters as a result of human-induced climate change. Thwaites already accounts for about 4% of annual sea level rise. Critical Antarctic ice shelf could fail within five years, scientists say “You can’t remove the Thwaites and leave the rest of Antarctica intact,” Alastair Graham, a marine geologist at the University of South Florida and co-author of the study, said in a telephone interview. He described the consequences of losing Thwaites as “existential”. According to the United Nations, more than 40 percent of the world’s human population lives within 60 miles of the coast – areas that will be hit hard by the tide. “Thwaites is really holding on today by its claws, and we should expect to see big changes on small time scales in the future – even from one year to the next – when the glacier retreats past a shallow ridge in its bed.” , said Robert Larter of the British Antarctic Survey, co-author of the study. Satellite images taken late last year revealed that an ice shelf used to stabilize the eastern part of Thwaites Glacier has shown signs of cracking – which scientists say could lead to a ‘spider’ effect across the wedge if hit with strong winds, according to The Washington Post. The researchers say, however, that the collapse of the continental shelf would not immediately contribute to sea-level rise, although it could accelerate the erosion of Thwaites Glacier by collapsing ice caps from the structure into the sea. Graham said his team could not predict with certainty if or when the glacier structure could completely dissolve, but that reducing global warming emissions over the next 75 years would be critical to its survival. “Right now, we can do something about it — especially if we can stop the ocean from warming,” he said.
