After years of suspense and nervously sweating scientists, it’s looking like the crack in the Larsen C ice shelf is finally in its final months. Once this giant ice crack works its way to the Antarctic’s edge, it will chop off a portion of ice larger than Rhode Island.
Project MIDAS has acquired new data from ESA’s Sentinel-1 satellites that show the Larsen C ice shelf has cracked another 17 kilometers (11 miles) between May 25 and May 31, 2017. This means that the crack is just 13 kilometers (8 miles) from the edge of the shelf and quickly heading its way.
These things are notoriously hard to predict and there have been endless reports of the crack being “about to break away” over the past year (as you may have noticed). However, project leader Professor Adrian Luckman has stated: "If it doesn't go in the next few months, I'll be amazed.”
"There hasn't been enough cloud-free Landsat images but we've managed to combine a pair of ESA sentinel-1 radar images to notice this extension, and it's so close to calving that I think it's inevitable," he added.
The crack is a big deal for a few reasons. When the crack reaches the edge, it will create a 5,000 square kilometer (1,930 square mile) piece of ice, that’s one of the biggest recorded icebergs ever. Since the ice shelf holds back a lot of glacier water from entering the sea, it’s estimated the shelf's disappearance will cause global waters to rise by 10 centimeters (3.9 inches).
"The eventual consequences might be the ice shelf collapse in years to decades," said Professor Luckman. "Even the sea level contribution of this area is not on anybody's radar; it's just a big geographical event that will change the landscape there."
The Larsen Ice Shelf is actually a series of shelves that’s been breaking up since the 1990s. The Larsen A ice shelf broke off in 1995 and there was also the sudden break-up of the Larsen B shelf in 2002. Although many scientists believed that climate change has made the cracks grow quicker, the event is best described as a geographical event rather than a climate event.
"We are convinced, although others are not, that the remaining ice shelf will be less stable than the present one," said Professor Luckman.
"We would expect in the ensuing months to years further calving events, and maybe an eventual collapse – but it's a very hard thing to predict, and our models say it will be less stable; not that it will immediately collapse or anything like that."