Overview

• A23a has fractured into several large pieces north of South Georgia, with researchers counting fragments up to A23f and warning the remnants could soon be too small to track.
• The berg has shrunk to roughly 1,700 square kilometers and has ceded the “largest iceberg” title to D15A, which spans about 3,000 square kilometers.
• British Antarctic Survey expects the pieces to keep circling counterclockwise around South Georgia and drift toward the northeast as breakup accelerates.
• Calved in 1986 from the Filchner–Ronne Ice Shelf, A23a stayed grounded for decades, detached around 2000, and has melted faster since moving into waters above freezing in early 2024.
• Researchers note iceberg calving is natural, but warmer oceans and altered circulation can destabilize ice shelves; melting ice shelves and glaciers are projected to raise sea levels substantially, though estimates carry wide uncertainty.