What we know about iceberg A23a and its collision course with a remote British island

Iceberg A23a is on a collision course with the remote British island of South Georgia, which provides an Antarctic haven for penguins and seals.

ist mit mehr als 4000 km² der aktuell größte Eisberg der Welt (Stand: Dezember 2024).[1][2] Seine Fläche entspricht ungefähr der Fläche der Insel Mallorca. Er weist ein Gewicht von etwa 1 Billion Tonnen auf.Er ist vor rund 40 Jahren aus dem Filchner-Ronne-Schelfeis. frei und bewegt sich nach einer langen Pause auf Südgeorgien zu. Dort bedroht er eine empfindliche Tier- und Pflanzenwelt - auch und gerade durch weil durch das Abschmelzen sehr viel Süßwasser in den Südatlantik gelangt und damit die Lebensbedingungen von Krill gefährdet. Der Eisberg ein Tafeleisberg. Er ist oben völlig eben.
The iceberg is around three times the size of the Peak District. (Getty)

The world’s largest iceberg is heading towards a remote British island of South Georgia in the South Atlantic Ocean and could threaten millions of penguins and seals that live there.

The huge iceberg A23a measures almost 1,500 square miles, roughly twice the size of Greater London, and is as tall as the Shard in London.

Dr Andrew Meijers, physical oceanographer at British Antarctic Survey told Yahoo News that the collision may have a deadly impact on baby seals and penguins.

After the iceberg broke off from one of the ice shelves four decades ago, it immediately grounded on the shallow ocean bottom. It has since spent three years slowly meandering northwards.

Millions of penguins and seals live on South Georgia. (Getty)
Millions of penguins and seals live on South Georgia. (Getty)

"It wasn’t until the end of 2023, that it came out, and that was when I encountered it on a research vessel," Dr Meijers said.

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Millions of seals, penguins, and seabirds breed on South Georgia and forage in the surrounding waters.

Dr Meijers said: "People might be worried that it's likely to come into contact with South Georgia in the next two or four weeks. South Georgia is home to fur seals and penguins, and currently, they're in the middle of their breeding.

"So if it grounds, it will disrupt their access to food supplies, which means a lot of the chicks and pups are likely to die. That’s on top of a bad season already, because bird flu is affecting seals and penguins in the region.

ANKARA, TURKIYE - JANUARY 23: An infographic titled
(Getty)

The iceberg calved off West Antarctica's Filchner-Ronne Ice Shelf in 1986 and previously hosted a Soviet research station.

For many years, it was stranded after its base became stuck on the floor of the Weddell Sea but in 2023 it broke off and started moving until it eventually passed the northern tip of the Antarctic Peninsula.

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"It is presently in a meander of the current and not moving directly towards the island," Dr Meijers said. "But our understanding of the currents suggest that it is likely to again move towards the island soon.

ist mit mehr als 4000 km² der aktuell größte Eisberg der Welt (Stand: Dezember 2024).[1][2] Seine Fläche entspricht ungefähr der Fläche der Insel Mallorca. Er weist ein Gewicht von etwa 1 Billion Tonnen auf.Er ist vor rund 40 Jahren aus dem Filchner-Ronne-Schelfeis. frei und bewegt sich nach einer langen Pause auf Südgeorgien zu. Dort bedroht er eine empfindliche Tier- und Pflanzenwelt - auch und gerade durch weil durch das Abschmelzen sehr viel Süßwasser in den Südatlantik gelangt und damit die Lebensbedingungen von Krill gefährdet. Der Eisberg ein Tafeleisberg. Er ist oben völlig eben.
Experts now fear the iceberg could stop seals and penguins feeding in South Georgia. (Getty)

"The current follows the shallow continental shelf around the island to the southeast, but the question is whether the berg will follow this out into the open South Atlantic, or run up onto the shelf and become stuck for some time."

The iceberg could ground against the island, meaning that the many seals and penguins which live there could be unable to access food.

The iceberg is currently 173 miles away from the island, according to the BBC.

Antarctica - December 26th 2023 - Photo of A23a Iceberg Wide View from Cruise Ship Behind Crowd. Passenger Photographs From Staircase Camera
Cruise ship passengers look at A23a in December 2023. (Getty)

Large slabs of ice are already breaking off A23a, and experts fear it could break into segments which could hang around South Georgia for years.

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"If this happens it could seriously impede access to feeding grounds for the wildlife - seals and penguins mostly - that breed on the island," Dr Meijers explained.

In 2020, another gigantic iceberg, A68, stirred fears that it would collide with South Georgia.

Researchers feared that the iceberg would end up crushing marine life on the sea floor and cutting off food access, but the iceberg eventually broke into smaller chunks.

The root cause of the melting of such huge icebergs is climate change, Dr Meijers said. "This iceberg is a natural phenomenon, but it really does represent an increase in the ice loss of Antarctic ice shelves.

"Since 2020, the ice shelves have lost six trillion tons of ice. They've gotten smaller by then amounts, and that's due to climate change."