One of Antarctica’s largest ice shelves just received some bad news. The crack running along the middle of the ice shelf, already quite long, has apparently grown by an alarming 11 miles. Researchers now fear that it is only a matter of time, as short as a couple of months, until the crack becomes a break and part of the ice shelf floats away forever.
The crack
The newest crack is on an ice shelf named Larsen C. Larsen C is more than 1000 feet thick, meaning it takes some pretty powerful forces to crack this ice. In its entirety, Larsen C is almost the size of Scotland, making it the fourth largest ice shelf in Antarctica. The additional 11 mile crack that was recorded joins a crack in Larsen C that has been in place since 2010. Sadly, the crack, also known as a rift, is growing larger every year. This 11 mile growth, for instance, occurred between the beginning of December 2016 to present day. This follows a 13 mile growth recorded earlier in 2016. Since 2011, the crack has grown 50 miles. The rift is currently almost 100 miles long and over 1000 feet wide. There are only 12 miles between the edge of the crack and the edge of the sea. Only 12 miles separate this chunk of ice shelf from breaking off for good.
What happens if it breaks off?
If the crack grows long enough for the ice shelf to break, a piece of ice roughly 2000 square miles will detach from the ice shelf. 2000 square miles is approximately the size of the state of Delaware. This loss will be 10% of Larsen C’s area and will leave the ice shelf at its most receded position in history. With a receded area, Larsen C will be more vulnerable to future cracks and rifts. Ice shelves in Antarctica work to protect the glaciers and keep them frozen. If the shelves are vulnerable and unstable, they are unable to adequately keep Antartica’s glaciers from melting into the ocean. This would lead to global rises in sea level.
Due to the instability of Larsen C, the British Antarctic Survey team refused to camp on the surface this year. Over the years, Larsen C has also suffered from ice thinning, as well as the reported rift. Many researchers believe the cause of these rifts and ice thinning is global warming. Overall, the Antarctic Peninsula is warming and the earth’s seas are warmer on average, both thought to be caused by climate change.
Have we seen this before?
Unfortunately, Larsen C is not the first Antarctic ice shelf to be at risk. Two smaller ice shelves, Larsen A and Larsen B have all but disappeared. In 2002, Larsen B had a large rift in it, similar to the one in Larsen C right now. The rift caused the ice shelf to crack, collapse and essentially disintegrate. After the collapse of Larsen B, the glacier it was protecting began to speed up and flow into the sea at an alarming rate. The fear is that Larsen C may be following in the alarming footprints of Larsen B.
According to leading researchers, it’s not so much a matter of if Larsen C will break off and collapse like its brother ice shelf, but rather when. As Adrian Luckman, head of Project MIDAS, put it, “if it doesn’t go in the next few months, I’ll be amazed.” Luckily, Antarctica is home to other thicker sheets of ice such as the West Antarctic and East Antarctic ice sheets. But researchers are doubtful that even the thickest ice at the southern pole will be able to withstand the ill-effects of human caused climate change.