The world’s biggest iceberg, known as A23A, is crumbling after drifting in the Southern Ocean for almost forty years. Scientists have confirmed that the megaberg, which calved from Antarctica’s Filchner Ronne Ice Shelf in 1986, is now collapsing rapidly and could disappear entirely within weeks.
Once covering nearly 4 000 square miles and weighing close to one trillion tons, A23A was larger than Rhode Island and twice the size of London. For decades it remained lodged in the Weddell Sea before beginning to drift in 2020. Recent satellite images show that the iceberg has lost more than half its original size, with massive chunks breaking off, including some nearly 400 square miles in area.
Researchers warn that the final collapse could happen suddenly, with entire sections disintegrating in a matter of hours as warmer spring temperatures and stronger ocean currents take their toll. Although melting icebergs do not directly raise sea levels, the speed of A23A’s demise highlights the accelerating changes in Antarctica’s fragile ice systems and the broader threat of climate change.
The title of the world’s largest iceberg has already passed to D15A, but A23A’s dramatic end carries symbolic weight. It represents both the natural cycle of Antarctic ice and the increasing influence of human driven warming on the polar environment. Scientists say its story provides crucial insights into how ice shelves and glaciers may respond in the years ahead, shaping future sea level risks and the health of global marine ecosystems.
For many, the fall of A23A is more than the end of a floating island of ice. It is a reminder of the scale of change happening at the ends of the Earth and a warning of what could come if warming trends continue unchecked.