They found that at some point over the past two centuries, the base of the glacier had broken away from the seabed and retreated at a rate of 2.1 kilometers per year. This is double the rate observed by scientists over the past decade.
This rapid decay may have happened “as recently as the mid-20th century,” Alastair Graham, the study’s lead author and a marine geophysicist at the University of South Florida, said in a press release. .
This suggests that the Thwaites has the ability to undergo a rapid retreat in the near future, once it has moved away from a seabed ridge that helps keep it in check.
“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, a marine geophysicist and one of the study’s co-authors from the British Antarctic Survey, said in the statement.
The Thwaites Glacier, located in West Antarctica, is one of the largest on the planet and is larger than the state of Florida. But that’s just one faction of the West Antarctic Ice Sheet, which contains enough ice to raise sea levels up to 16 feet, according to NASA.
With the climate crisis accelerating, this region has been closely watched due to its rapid melting and capacity for widespread coastal destruction.
The Thwaites Glacier itself has preoccupied scientists for decades. As early as 1973, researchers wondered if it presented a high risk of collapse. Nearly a decade later, they discovered that – because the glacier is anchored to a seabed rather than dry land – warm ocean currents could melt the glacier from below, destabilizing it from below.
In the 21st century, scholars began documenting the rapid retreat of the Thwaites in a series of alarming studies.
“From satellite data, we see these large fractures propagating across the surface of the pack ice, essentially weakening the ice fabric; a bit like a crack in a windshield,” said British Antarctic oceanographer Peter Davis. Survey. CNN in 2021. “It spreads slowly over the sea ice and eventually fractures into many different pieces.”
Monday’s findings, which suggest the Thwaites is capable of retreating at a much faster rate than recently thought, were documented during a 20-hour mission in extreme conditions that mapped an area under Houston-sized navy, according to a press release.
Graham said this search “was truly a once-in-a-lifetime mission”, but the team hopes to return soon to collect seafloor samples so they can determine when previous rapid retreats occurred. This could help scientists predict future changes to the “doomsday glacier”, which scientists had previously assumed would be slow to change – something Graham said this study disproves.
“Just a little kick to the Thwaites could lead to a big response,” Graham said.