As climate change accelerates, the Thwaites Glacier, called the Doomsday Glacier, is also changing rapidly.
It throws billions of tons of ice into the ocean each year, which is about 4% of the annual rise in sea level. Particularly rapid melting occurs at the point where the glacier meets the seafloor, which has retreated about 14 kilometers since the late 1990s, exposing a larger chunk of ice to relatively warm ocean water.
Thwaites’ complete collapse could cause sea levels to rise more than 70 centimeters, enough to flood many cities.
The ice shelf could collapse much sooner than previously thought.
To better understand its changes, a group of American and British scientists from the International Thwaites Glacier Society visited the glacier.
They drilled a 600-metre-deep hole in the ice using a hot-water drill and sent various instruments to take measurements in the glacier over the course of five days.
A torpedo-like robot called Icefin was sent, allowing them to access areas that were nearly impossible to explore before. The remote-controlled device took pictures and recorded information about the temperature and salinity of the water, as well as ocean currents.
“It was really able to gather data from the seafloor by swimming to dynamic places,” he said. CNN Britney Schmidt is an associate professor at Cornell University and lead author of one of the articles on the subject.
Peter Davies, an oceanographer with the British Antarctic Survey and lead author of another paper, said the results of the study paint a “very fine and complex picture”.
The scientists found that the rate of melting under the flat part of the ice shelf was slower than expected, even as the glacier retreated. The melting rate averaged between 2 and 5.4 meters per year, which is less than anticipated, according to the study.
Melting is being suppressed by a layer of colder, fresher water at the base of the glacier, between the ice shelf and the ocean, according to the study.
“The glacier is still in trouble,” Davis concluded in a statement. “We found that despite some melting, the glacier is still retreating rapidly, so it doesn’t seem like much effort is needed to get the glacier out of balance.” .