Megaberg A23A has crash landed near the British overseas territory of South Georgia, an island in the southern Atlantic Ocean home to just 1,000 people and unique animals
Brits narrowly avoided a clash with the world’s largest iceberg when it ran aground on an island earlier this week.
The “megaberg”, officially designated Iceberg A23A, came to rest near South Georgia, grinding onto the edge of the British overseas territory’s continental shelf between March 2 and 3. Scientists traced the ice block, a remnant of the Antarctic Filchner ice shelf that has been on the move for nearly 40 years, to the southwest of the landmass, after it made a six-week northern turn over January and February.
The British Antarctic Survey (BAS), which is observing the nearly trillion tonne slab, is now just 73 kilometres (45 miles) off the coast of the island, which is home to around 1,000 people and a growing population of seals, penguins and a host of unique birds. They now stand to benefit from the dramatic shift, which is expected to bring some local ecological changes.
Dr Andrew Meijers, an oceanographer at the British Antarctic Survey, said the continued grounding is unlikely to cause “significant” changes to the local ecology. But he added it could stir up nutrients from the seafloor that make new food available for the island’s most “charismatic” inhabitants.
He said: “If the iceberg stays grounded, we don’t expect it to significantly affect the local wildlife of South Georgia. In the last few decades, the many icebergs that end up taking this route through the Southern Ocean soon break up, disperse and melt.” Dr Meijers added: “Nutrients stirred up by the grounding and from its melt may boost food availability for the whole regional ecosystem, including for charismatic penguins and seals.”
While animals may see a net benefit from the iceberg’s movements, the official said it may disrupt commercial fishing operations. Dr Meijers said: “Commercial fisheries have been disrupted in the past however, and as the berg breaks into smaller pieces, this might make fishing operations in the area both more difficult and potentially hazardous.”
Satellite tracking imagery appears to show the iceberg is keeping its shape, at least for the time being, Dr Meijers said, meaning additional disruption is unlikely in the near future. Scientists will take the opportunity to explore how the iceberg affects local ecology.
Iceberg A23A was released into the Weddell Sea in 1986 during a major breakaway, and spent more than 30 years grounded on the sea floor before it started drifting in 2020. Before making landfall on South Georgia, the ice sheet had been moving through warmer Southern Ocean currents.
The British territory of South Georgia has no indigenous population but is home to researchers and supporting staff.
