A23a broke off the Filchner Ice Shelf in 1986, about 4,000 km² of ice. It then sat aground in the Weddell Sea for more than 30 years. In 2020 it floated free. Over Pirie Bank a rotating column of water trapped it for most of 2024, and in March 2025 it ran aground off South Georgia. It then drifted north into warmer water and broke apart in early 2026. After the breakup the track follows the largest remaining piece. The berg is drawn to scale.
Source: Track and size: Brigham Young University Antarctic iceberg database (U.S. National Ice Center and satellite data). Sea ice and seabed: E.U. Copernicus Marine Service GLORYS reanalysis (GLOBAL_MULTIYEAR_PHY_001_030)
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