One of the planet’s best-observed ice shelves has just undergone a major change. On Sunday, a huge chunk of Antarctica’s Brunt Ice Shelf — a chunk the size of two New York cities — broke loose.
The British Antarctic Survey said on Monday that the iceberg is 1,550 square kilometers in size.
This is the second major ice shelf breakdown, known as calving, in two years, though scientists have long predicted it will happen. Cracks have been developing naturally throughout the ice shelf for a decade, according to the British Antarctic Survey.
The Brunt Ice Shelf lies across the Weddell Sea from the site of another ice shelf that has made headlines, the Larsen C Ice Shelf in the Antarctic Peninsula. Last year, the— which was about the size of New York City and long considered stable — .
It was the first time in human history that Antarctica had collapsed like this. It happened after onebrought unusually warm air to the region, with many pointing to climate change as a possible factor.
But according to BAS glaciologist Dominic Hodgson, the latest breakup of an iceberg from Brunt “is not linked to climate change.”
“This calving is expected and part of the natural behavior of the Brunt Ice Shelf,” Dodgson said.
A large crack in the Brunt Shelf, known as a fissure, had been dormant for decades, but in 2012 scientists discovered a major change. It grew continuously from 2015, and by December last year, researchers said it “spread across the entire ice shelf.”
It is the second time in two years that an iceberg has calved off the ice shelf.
The latter, known as A74, emerged in February 2021 – less than 5 years after the formation of a new crack known as the Halloween Crack. It is slightly smaller than the last breakdown and has since drifted into the Weddell Sea.
The newest iceberg is named by the US National Ice Center. Researchers believe it will likely follow the path of the A74 out to sea.