The widening crack could break off an enormous chunck of ice - the size of Delaware
A crack in one of Antarctica’s largest ice shelves has grown enormously in the past few months and researchers suspect that it could dislodge an entire ice shelf. And this break off could lead to destabilize a larger area of Antarctic ice.
The ice shelf, called Larsen C, is the fourth largest ice shelf in Antarctica and is roughly the size of Scotland. Researchers from the British Antarctic Survey have been monitoring a crack on this ice shelf for years and they have found that crack is spreading across the ice shelf at an alarming speed. The crack grew around 18 miles in four years since the project MIDAS was started in 2011. Last year, it was more 600 feet wide and now it is around 1100 feet wide, extending at a jaw-dropping rate. If it continues to expand at the same rate, Antarctic will likely end up losing one of its big ice shelves. This will be the third largest loss of Antarctic ice after Larsen A and Larsen B which collapsed and disintegrated in 1995 and 2002 respectively.
“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,” wrote members of the Project MIDAS team in the blog.
“Computer modeling suggests that the remaining ice could become unstable, and that Larsen C will follow the example of its neighbor Larsen B, which disintegrated in 2002 following a similar rift-induced calving event.”
Since March, the last time when satellites were able to observe Larsen C, the crack has further grown 22 kilometers. Researchers speculate that we will loss around 6,000 kilometers of Antarctic ice in future, which is nearly the size of Delaware. But when will it happen, no one knows.
"It's hard to tell how soon it could break - we really don't have a good handle on the processes which control the timing of the crack propagation.”Martin O'Leary from MIDAS project told Washington Post.
"It's a lot like predicting an earthquake - exact timings are hard to come by. Probably not tomorrow, probably not more than a few years.”
Ice shelves act as gatekeepers which prevents glaciers floating on Antarctica from crashing into the ocean. Without them, glaciers cannot stabilize. They enter the ocean faster and accelerate the pace of global sea level rise.
Meanwhile, the MIDAS team will continue to monitor the rift and will assess its impact on ice shelf and more broadly Antarctica.