Iceberg A-81 approached South Georgia in late October 2026, more than three years after calving from Antarctica's Brunt Ice Shelf. NASA's Terra satellite acquired an image of the berg on October 20, 2026, using the MODIS instrument. The image was produced from MODIS data distributed through NASA's EOSDIS LANCE and GIBS/Worldview. NASA Earth Observatory published it as the Image of the Day for October 27, 2026. In the image, the iceberg sits at the boundary of the island's shallow underwater shelf. The image captured the berg as it slowed, not as it stopped.
A-81 is roughly 1,550 square kilometers, or 600 square miles, according to NASA Earth Observatory. That size was reported after the berg broke from the ice shelf. The berg left the Brunt Ice Shelf in January 2023. For more than three years, the clockwise Weddell Gyre carried it along the coast of the Weddell Sea. Fast is relative. Some icebergs linger close to home for decades, running aground near the ice shelves that spawned them. Others circle partway around the continent on coastal currents. A-81 instead took a route well traveled by the region's bergs and moved north out of the Weddell Sea. In May 2026, it rounded the tip of the Antarctic Peninsula. From there it crossed the Scotia Sea, and by late October it was at South Georgia, a remote island in the South Atlantic Ocean, roughly 2,300 kilometers (1,400 miles) north-northwest of the Brunt Ice Shelf.
South Georgia has stopped icebergs before
Two researchers, Jan Lieser of Australia's Bureau of Meteorology and Christopher Shuman of the University of Maryland (retired), reported that the berg slowed noticeably in the days before the October 20 image. It appeared to be bumping along the edge of the island's underwater shelf. South Georgia has affected icebergs before. In 2025, A-23A grounded on the shelf and later broke apart. The island has slowed or stopped bergs in earlier events. The shallow shelf around South Georgia is what caused the recent slowdown.
The Brunt Ice Shelf calved A-81 after a long wait
Becoming an iceberg took time. A rift in the Brunt Ice Shelf called Chasm 1 stayed relatively stable for about 35 years. Around 2012 it began growing again. By 2019 it was advancing quickly enough that a break seemed imminent. The ice held on for several more years before calving in January 2023.
Calving is a normal part of the life cycle of ice shelves. Scientists watch Brunt closely because it is home to the British Antarctic Survey's Halley Research Station, a major base for Earth, atmospheric and space science research since the 1950s. Brunt has recently shed several large icebergs in quick succession. It produced A-74 from the North Rift in 2021 and A-83 from the Halloween Crack in 2024. A-74 has since broken up. A-83 is still intact and follows A-81 north, with a handful of other bergs apparently leaving the Weddell Sea.
For anyone planning a voyage that includes South Georgia, the question to put to an operator is how current iceberg positions are being monitored around the island.