World’s Largest Iceberg Runs Aground Near South Georgia

 

World's largest iceberg, A23a, grounded on British island

The enormous iceberg known as A23a, currently the largest in the world, appears to have become stuck after drifting through the Southern Ocean near Antarctica for several years.

Weighing approximately a trillion metric tonnes (1.1 trillion tons), A23a has seemingly halted off the coast of South Georgia, a British Overseas Territory in the southern Atlantic Ocean. This information was revealed in a statement from the British Antarctic Survey (BAS) on Tuesday.

As of August 2024, the iceberg covered a vast area of 3,672 square kilometers (1,418 square miles), making it slightly smaller than Rhode Island but over twice the size of London.

Originally part of the Filchner Ice Shelf in Antarctica, A23a separated in 1986 and remained grounded in the Weddell Sea for over three decades before finally beginning its drift in 2020.

By late 2024, the iceberg’s journey was interrupted when it became trapped, rotating for months around an underwater mountain, delaying its expected movement northward.

After eventually breaking free, concerns arose that A23a might drift toward South Georgia, potentially obstructing access to crucial feeding areas for seals and penguins inhabiting the island.

However, these fears have lessened since the iceberg now appears to have settled on the continental shelf about 90 kilometers (56 miles) from the coastline.

Massive Iceberg on Collision Course with Wildlife-Packed South Georgia Island

“If the iceberg stays grounded, we don’t expect it to significantly affect the local wildlife of South Georgia,” said Andrew Meijers, an oceanographer at the BAS, in the statement.

On the other hand, its presence could offer ecological benefits.

“Nutrients stirred up by the grounding and from its melt may boost food availability for the whole regional ecosystem, including for charismatic penguins and seals,” he said.

Though A23a remains intact for now, past trends indicate that icebergs following a similar course often “soon break up, disperse and melt,” according to Meijers.

“Now it’s grounded, it is even more likely to break up due to the increased stresses, but this is practically impossible to predict,” he said in the statement.

“Large bergs have made it a long way north before – one got within 1000km of Perth Australia once – but they all inevitably break up and melt quickly after.”

When A23a eventually fractures, the resulting smaller icebergs will create navigational challenges for fishing and shipping, as they are harder to identify and track compared to a singular massive iceberg, Meijers explained.

“Discussions with fishing operators suggests that past large bergs have made some regions more or less off limits for fishing operations for some time due to the number of smaller – yet often more dangerous – bergy bits,” he said.

Scientists believe A23a’s detachment was a natural part of the ice shelf’s growth cycle, rather than a direct consequence of climate change linked to fossil fuel emissions.

However, global warming is causing alarming transformations in Antarctica, with potentially severe consequences for rising sea levels worldwide.