Iceberg Five Times the Size of New York Breaks Away From Antarctica

One of the largest icebergs in the world—which is roughly five times the area of New York City—is on the cusp of escaping from the waters around Antarctica after being stuck to the sea floor for 30 years.

A23a, which has an area of 1,500 square miles, broke away from the icy southern land mass in 1986, but became grounded in the Weddell Sea, which sits to the south of the South Georgia and South Sandwich Islands.

The iceberg has been drifting for a number of years, but is shortly expected to move beyond the Antarctic Peninsula that juts out towards the southern tip of South America, and is expected to move into the southern Atlantic Ocean.

Its movement since 2020 and beckoning release in open water has raised questions as to why it is occurring now, after nearly four decades.

"I asked a couple of colleagues about this, wondering if there was any possible change in shelf water temperatures that might have provoked it, but the consensus is the time had just come," Andrew Fleming, a remote sensing expert from the British Antarctic Survey, told the BBC.

"It was grounded since 1986 but eventually it was going to decrease [in size] sufficiently to lose grip and start moving," he added.

Newsweek approached the British Antarctic Survey via email for further comment on Friday.

Icebergs are one of several forms of ice sheet loss that contribute to rising sea levels; between 1992 and 2018, ice lost in Antarctica and Greenland raised sea levels by seven tenths of an inch. Rising sea and air temperatures caused by climate change is contributing to a greater amount of ice loss and is known to contribute to the calving of ice that forms icebergs.

A23a will now travel along what is known as one of the world's "iceberg alleys"—a current of water that travels around the continent, into the Weddell Sea before being pushed out by the Antarctic Peninsula, dragging icebergs along with it.

The ice that forms A23a was originally the site of a Soviet research station, Druzhnaya 1. After the ice shelf broke away, an expedition was dispatched to rescue the research station's equipment and airlift it to another one.

According to the NASA Earth Observatory, there used to be an even larger iceberg—one that held the title of largest— when it broke from Antarctica's Ronne Ice Shelf in May 2021.

Dubbed A76, it had an area of roughly 1,667 square miles. But within a month it had broken into three pieces.