80 Mile Crack Threatens Antarctic Ice Shelf
A huge crack that scientists found across a fragile ice shelf in Antarctica is continuing to widen and grow, a new study reveals.
For some time now, experts have been observing the progression of a large rift in Larsen C, the northernmost major ice shelf in Antarctica and the fourth largest ice shelf in the peninsula.
According to the new report, the crack is spreading across the ice shelf at a rapid rate and may eventually cause its collapse.
More specifically, scientists say the crack may carve out an iceberg the size of the state of Delaware. For comparison, Larsen C is just slightly smaller than Scotland in size.
No one knows for sure when this ice shelf collapse will happen, but when it does, it will be the largest calving event in the Antarctic peninsula since the turn of the century. It will also be the third biggest collapse ever recorded, as well as the largest from the Larsen C ice shelf.
Researchers from the British Antarctic Survey say Larsen C is called an ice shelf because its entirety is covered by a 350-meter thick ice that floats on top of deep ocean waters.
Between 2011 and 2015, the crack across the ice shelf grew 18.6 miles (30 kilometers), widening to about 200 meters in length. It has continued to grow since then.
Now, a group of scientists report that as the intense winter polar night over Antarctica comes to an end, they have been able to observe a glimpse of what happened to the rift when it could not be observed via satellite.
The scientists, who are part of Project MIDAS, found that the large crack had grown another 13.67 miles (22 kilometers) since it was observed in March, and has widened to about 350 meters. The full length of the crack is now 80 miles (130 kilometers), researchers say.
This means that it may only be a matter of time before an enormous part of Larsen C gets carved out of the ice shelf. MIDAS researchers say about 9 to 12 percent of Larsen C is expected to break off during the ice calving event.
Glaciologist Martin O’Leary, one of the study researchers, calculated that the amount of ice lost would be about 6,000 square kilometers (2,316 square miles).
Still, O’Leary says it is hard to predict when it will happen.
“It’s a lot like predicting an earthquake,” says O’Leary. “Exact timings are hard to come by.”