World's Largest Iceberg, Visible From Space, On Course To Collide With Remote British Island

A23a, the world's largest iceberg, weighing more than one trillion tons, is set on a collision course with a remote British island off Antarctica, according to a BBC report. Measuring nearly 3,900 square km at its peak -- roughly three times the size of New York City, the "megaberg", visible from space, is heading northwards from Antarctica towards South Georgia, regarded as a wildlife haven. As per experts, the iceberg is now just 280 km away from the British territory and is expected to make contact in two to four weeks, depending on the currents.

"South Georgia sits in 'iceberg alley' so impacts are to be expected for both fisheries and wildlife, and both have a great capacity to adapt," Mark Belchier, a marine ecologist who advises the South Georgia government, told the publication.

If the iceberg collides, its fragmented pieces could float around South Georgia uncontrollably for years, jeopardising the fate of king penguins as well as elephant and fur seals.

"If this happens (the iceberg grounding) it could seriously impede access to feeding grounds for the wildlife - seals and penguins mostly - that breed on the island," said Dr Andrew Meijers, an oceanographer with the British Antarctic Survey (BAS).

This is not the first instance when animals in the region are facing an existential crisis. In 2004, another iceberg named A38 grounded on its continental shelf in the north-east of South Georgia. The penguin and seal population declined as they were prevented from using their foraging routes due to massive ice chunks blocking the way.

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Journey of A23a

The journey of iceberg A23a has been a collection of fascinating scientific events. 'The megaberg' broke free from the Filchner Ice Shelf in 1986 but got stuck in the Weddell Sea's bottom mud for 30 years. It remained a static "ice island" until 2020 when it finally began to drift again. Slowly at first, it then accelerated northward, moving towards warmer air and waters.

For several months, the iceberg was trapped in a rare oceanographic phenomenon known as a Taylor Column, where rotating water above a seamount held it in place. This unusual event caused A23a to spin in a single spot, delaying its expected rapid drift north.

However, in December 2024, it broke free and started its rapid descent down south. Scientists around the world are now anxiously checking satellite pictures to monitor the daily movements of the iceberg and hoping that it somehow avoids the island.