March 4 (UPI) -- The oldest and largest iceberg on Earth landed on a sub-Antarctic island belonging to Britain Tuesday.
According to the British Antarctic Survey research organization, the mass known as A23a has stopped drifting and run aground on South Georgia, an unpopulated island that is part of the British Overseas Territory of South Georgia and the South Sandwich Islands and is approximately 932 miles from the Falkland Islands.
Estimated to weigh roughly a trillion tons, A23a had broken away, or calved, from Antarctica's Filchner Ice Shelf in 1986 and then stayed atop the seabed in the Weddell Sea within the Southern Ocean for more than 30 years. It then began drifting toward South Georgia in 2020, but in late 2024 the iceberg got stuck within a Taylor Column, an oceanographic phenomenon where water spins objects while keeping them in place, and delayed A23a's anticipated northward drift.
Speaking with the media, oceanographer Dr. Andrew Meijers said now that A23a is grounded, "it is even more likely to break up due to the increased stresses," but that its fate is "practically impossible to predict."
He also explained that while icebergs are part of the normal lifecycle of the Antarctic ice sheet, about 6,000 billion tons of its mass has been lost since 2000, and that has been matched by increasing melting of ice shelves and a measured loss of grounded Antarctic ice "attributed to anthropogenic climate change."
South Georgia is home to penguins, seals and albatross, among other wildlife, and while Meijers says A23a is not likely to impact the animals, it could possibly "interrupt their pathway to feeding sites and force the adults to expend more energy to travel around it," which could make it harder for the resident birds to properly feed their young. However, in his opinion, "if the berg is stimulating ocean productivity, this could actually boost populations of local predators like seals and penguins."
Meijers also notes that as A23 continues to break up, it could create smaller icebergs that might make some regions dangerous for fishing operations.
