The world's biggest iceberg, A23a, is on the move after 30 years: Is it a concern?

Scientists around the world are concentrating on the world’s largest iceberg which was formerly part of Antarctica. The iceberg, named A23a, is finally on the move after being stuck to the ocean floor for more than 30 years. Here’s all we know about it. Meet A23a – the world’s largest iceberg A23a is a massive iceberg that is more than twice the size of Greater London, covering an area of about 4,000 square kilometres. The iceberg broke away from the Antarctic coast in 1986, but it became stuck in the Weddell Sea and resembled a sort of “ice island.”

A23A, The World's biggest iceberg is on the move after being stuck to the ocean floor for more than 30 years. It split from the Antarctic coastline in 1986 but soon grounded in the Weddel Sea to become an ice island. The behemoth is 4,000 sq km (1,500 sq miles) in area, more... pic.twitter.com/VR01Gk6B4s

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It was a part of a massive berg outburst from the Filchner Ice Shelf on the White Continent. Its hosting of a Soviet research station at the time only serves to highlight how long ago its calving took place. Fearing that the equipment at the Druzhnaya One base would be lost, Moscow sent out an expedition to retrieve it. The tabular berg, however, didn’t travel far from the coast before its thick keel fixed it firmly to the bottom muds of the Weddell. It is on the move… Dr Andrew Fleming, a remote sensing expert from the British Antarctic Survey told BBC News, “I asked a couple of colleagues about this, wondering if there was any possible change in shelf water temperatures that might have provoked it, but the consensus is the time had just come. It was grounded since 1986 but eventually it was going to decrease (in size) sufficiently to lose grip and start moving. I spotted first movement back in 2020.” The winds and currents in recent months have accelerated the movement of A23a. Weddell sector icebergs, such as A23a, typically follow the Antarctic Circumpolar Current and pass via “iceberg alley,” a route that explorer Ernest Shackleton took in 1916 following the sinking of his ship, the Endurance.

Amongst my most popular enhancements is this beauty, from a colour paget plate by Frank Hurley. It's Sir Ernest Shackleton's ship Endurance - looking as though it is sailing the clouds - taken shortly before its sinking in the Antarctic in 1915. Its wreck was discovered last year pic.twitter.com/f0jcFgk81f

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What happens next Experts are predicting that the huge iceberg will be thrown towards the southern South Atlantic Ocean, close to the island of South Georgia, which is home to large icebergs sitting offshore. Millions of seals, penguins, and other birds live on this island. There is concern that A23a could disrupt South Georgia Island’s ecology if it gets close to the island. The regular feeding routes of seals, penguins, and seabirds may be disturbed if grounding occurs in this area. The importance of icebergs to the environment cannot be understated, notwithstanding possible disturbances. Mineral dust, essential nutrients that maintain the base of sea food cycles, is released as they melt. Scientists are now keeping a careful eye on A23a’s progress. With inputs from agencies