Trillion-tonne 'A23a megaberg', the world’s biggest iceberg, breaks away

The world’s largest iceberg, A23a, breaks free and begins its journey through the Southern Ocean.

Listen to article

The world’s largest and oldest iceberg, A23a, has finally broken free after being stuck on the seafloor for over 30 years.

This massive iceberg, which weighs more than one trillion tonnes and is double the size of Greater London, was calved from Antarctica’s Filchner Ice Shelf in 1986.

@reuters

A nature photographer captures the A23a iceberg, the world's largest, during a trip on the Antarctic Ocean. #News #Reuters #A23a #iceberg #ocean #Antarctica

♬ original sound - Reuters

It remained grounded in the Weddell Sea, spinning in place due to a unique oceanic phenomenon, the Taylor Column, which trapped it until 2020 when it began drifting north.

Now, A23a has broken free and is expected to continue its journey through the Southern Ocean. Scientists predict it will follow the Antarctic Circumpolar Current, eventually moving towards South Georgia Island.

In warmer waters, the iceberg will likely break into smaller pieces and melt. Dr. Andrew Meijers from the British Antarctic Survey, who co-leads the Ocean:Ice project, expressed excitement about the iceberg’s movement, noting that it will provide valuable insights into the route of large icebergs and their effects on local ecosystems.

A year ago, scientists aboard the British Antarctic Survey’s RRS Sir David Attenborough captured the first images of A23a as part of their Biopole project.

The mission focused on studying how icebergs influence the ocean’s carbon and nutrient cycles. The researchers collected water samples to examine how the iceberg’s passage could impact marine life and the global carbon balance.