World’s largest iceberg on collision course with island – putting millions of penguins in danger

It is twice the size of London and 130 feet tall.

A23a - dubbed the 'megaberg' - is a trillion-tonne slab of ice which broke free from its position last month and started drifting northwards.

A23a, the world's current largest iceberg

It broke away from Antarctica's Filchner-Ronne Ice Shelf back in 1986!
After being stuck for decades, this icy giant, roughly the size of Rhode Island, has been on the move since 2020.

Now, A23a is making waves in the Southern Ocean,… pic.twitter.com/mubuTkZfMS

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Experts have warned that the roaming iceberg is on a collision course with the British territory of South Georgia, posing a huge threat to the island's rich wildlife.

It is scheduled to hit the remote island in three to four weeks, and could block vital pathways for penguins to get food for themselves and their chicks.

If the iceberg gets wedged in the shallow waters close to the island, parent penguins will be forced to swim further in order to retrieve food for their offspring - burning more energy and putting both them and their babies at risk of starvation.

The imminent geographical disaster could "dramatically increase mortality rates" among penguins, according to British Antarctic Survey physical oceanographer Andrew Meijer - something that has happened in the past.

Meijer - who examined the "colossal" iceberg up close in December 2023 when it drifted past the research ship RRS Sir David Attenborough - told Oceanographic Magazine: "It's a huge wall, a Game of Thrones-style wall of ice that towers above the ship.

"South Georgia is an amazingly ecologically rich island. It's a breeding ground for a huge number of penguins, millions of penguins and seals," Mr Meijers added.

"There's lots of pups and chicks and they're all still dependent on their parents."

The iceberg started moving for the first time in more than three decades in November 2023.

Before then, it had largely been stranded after its base became stuck on the floor of the Weddell Sea.

Eventually, the A23a will break up into smaller icebergs and melt as icebergs do, Mr Meijers confirmed.