A massive rift is threatening Antarctic Larsen C ice shelf to collapse

Image credit: NASA

New Delhi: Scientists have found that a huge crack is spreading at an alarming rate in one of the world’s biggest ice shelves - Larsen C, which is also the fourth largest Antarctic ice shelf overall.

For almost two years now, researchers from Project MIDAS, a British Antarctic Survey that involves teams from several UK universities, have been tracking the progress of a large rift in the Larsen C Ice Shelf.

They said that this rift, which may threaten the stability of Larsen C, has grown significantly and rapidly during the Antarctic polar night, which is now coming to an end.

As of August 2016, the rift had grown another 22 kilometres in length since it was last observed by satellites in March this year, and has widened to about 350 meters. Researcher said that the full length of the rift is now 130 kilometres.

Researchers say as this rift continues to extend, it will eventually cause a large section of the ice shelf to break away as an iceberg.

“We previously showed that this will remove between nine and twelve percent of the ice shelf area and leave the ice front at its most retreated position ever. The trajectory of the rift now implies that the higher of these two estimates is more likely,” researchers report in a blog.

“Computer modeling suggests that the remaining ice could become unstable, and that Larsen C may follow the example of its neighbour Larsen B, which disintegrated in 2002 following a similar rift-induced calving event,” they add.

The Larsen ice shelf is divided into three smaller ice shelves - Larsen A, B, and C. Larsen A and B have already experienced massive declines over the past two decades. The Larsen A ice shelf disintegrated in January 1995.

Researchers warn it may be only a matter of time before we see the loss of a massive chunk of Larsen C ice shelf, and when that happens it'll be the third largest loss of Antarctic ice recorded in history.

If Larsen C loses all its ice, scientists have estimated that it would raise global sea levels by 10 centimeters, or just under 4 inches.

The MIDAS Project will continue to monitor the development of the rift and assess its ongoing impact on the ice shelf.