New footage has shown Antarctica’s Thwaites Glacier is shrinking from below in a way scientists didn’t expect — rapid melting is taking place along cracks at its base.
Although ice loss is slower than expected elsewhere, the 130 km (80 mi) wide glacier (the “Doomsday River”) could contribute more than 65 cm (25 in) of sea level rise. or so. The point where the glacier meets the ocean and seabed, known as the “land line”, has already receded 14 kilometers. [8.7 ميل] Since the 1990s, the amount of ice flowing from the area has nearly doubled.
Using a combination of remote sensing and underwater images taken by a robot, a team of researchers from the US and UK was able to observe the process directly under the Thwaites Glacier for the first time.
The researchers saw that the warm water formed balcony-like structures at the base of the ice shelf. In these areas, in addition to cracks, melting occurred faster than expected.
The results of an interdisciplinary study of the two studies were published in the journal Nature this week.
“These new ways of looking at the glacier allow us to understand that it’s not just about how much melting occurs, but how and where it happens in these very warm parts of Antarctica,” said Cornell University geologist Brittney Schmidt.
“Warm water penetrates the weakest parts of the iceberg and makes it worse,” Schmidt said in an interview with Reuters.
Over nine months of observations, the water near the ground line became warmer and saltier, but the rate of melt remained constant at 2 to 5 meters per year – less than predicted by computer models.
The team then took the Icefin robot through the well and found stepped terraces, cracks, or faults.
Cracks have also been seen along the surface of the glacier, prompting scientists to predict that they could one day play a major role in the collapse of the glacier.
“Our results are amazing, but the glacier is still in trouble,” says Peter Davies, an oceanographer with the British Antarctic Survey.
Source: Science Alert
