Antarctica’s Thwaites Glacier, nicknamed the “Doomsday Glacier” due to its potentially catastrophic impact on sea levels, may dissolve faster than previously expected, according to a recent study.
New data and sea floor images published Monday in Nature Geoscience found the Florida-sized ice behemoth experienced a “rapid retreat” in the previous two centuries — and predicted that history may repeat itself in the near future.
A total loss of the glacier and its surrounding icy basins could raise sea levels from three to 10 feet, the researchers said.
Thwaites is already in a phase of “collapse” when viewed on geological time scales, yet new sea floor images suggest it once retreated at double its current rate — a pace of 2.1 kilometres per year — over a span of less than six months within the previous two centuries.
“Thwaites is really holding on today by its fingernails,” said Robert Larter, marine geophysicist with the British Antarctic Survey and study co-author, in a news release.
“We should expect to see big changes over small time scales in the future — even from one year to the next — once the glacier retreats beyond a shallow ridge in its bed,” he continued.
Through analyzing ridges on the sea floor, the scientists were able to map out the glacier’s movements as it bobbed along with the tide. This ‘map’ showed the rapid change occurred once the front of Thwaites detached from the seabed ridge that kept it grounded.
Currently, Thwaites is releasing 50 billion tons of ice into the water every year, accounting for four per cent of global sea level rise, according to the National Snow and Ice Data Centre. However, this study and recent ones like it suggest this pace can change rapidly.
For example, satellite images from late 2021 found a critical ice shelf holding the Thwaites Glacier together could shatter within the next few years.
Although scientists once thought of ice sheets as slow to respond, it’s becoming evident that this is not true, Alastair Graham, marine geophysicist at University of South Florida’s College of Marine Science and author of the study, said in the release.
“Just a small kick to Thwaites could lead to a big response,” he said.
https://news.google.com/__i/rss/rd/articles/CBMiywFodHRwczovL3d3dy50aGVwZXRlcmJvcm91Z2hleGFtaW5lci5jb20vdHMvbmV3cy93b3JsZC8yMDIyLzA5LzA2L2EtZG9vbXNkYXktZ2xhY2llci10aGUtc2l6ZS1vZi1mbG9yaWRhLW1heS1tZWx0LWZhc3Rlci10aGFuLWV4cGVjdGVkLXN0dWR5LWZpbmRzLmh0bWw_bGlfc291cmNlPUxJJmxpX21lZGl1bT10aGVwZXRlcmJvcm91Z2hleGFtaW5lcl93b3JsZNIBAA?oc=5
2022-09-07 01:50:31Z
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