NASA says a giant iceberg twice the size of all five New York City boroughs combined could soon break off the Brunt Ice Shelf in Antarctica.
Should the 660 square miles section separate, it would be the biggest iceberg to do so since monitoring of the ice shelf began with British explorer Ernest Shackleton’s survey in 1915.
The chasm that could lead to the break had been dormant for 35 years until 2012, when satellites first detected signs of activity, according to the British Antarctic Survey. It is now advancing North about 2.5 miles per year towards a West-East split in the ice known as the Halloween Crack, which was first detected in October 2016.
Once the two meet splits meet, it’s anticipated that a vast section of ice will detach from the shelf. While there are larger icebergs in the area, this could create further deterioration of the ice shelf, and possibly even lead to its break up.
“We don’t have a clear picture of what drives the shelf’s periods of advance and retreat,” NASA glaciologist Chris Shuman told IBT. “The likely future loss of the ice on the other side of the Halloween Crack suggests that more instability is possible, with associated risk.”
In recent years the rise in global temperatures has sped up the rate of ice loss on Antarctica, causing several large icebergs to break off, including a massive Delaware-sized berg that detached from the Larsen C Ice Shelf in July, 2017.
Researchers in Antarctica are trying to find out more about natural periods of fluctuation in the ice by searching for million-year-old ice cores that will contain valuable information about temperatures and atmospheric composition.