The world's largest iceberg is [1]now breaking apart rapidly in warmer waters after nearly 40 years adrift. "Earlier this year, the 'megaberg' known as A23a weighed a little under a trillion tons and was more than twice the size of Greater London," reports The Guardian. "It is now less than half its original size, but still a hefty 1,770 sq km (683 sq miles) and 60km (37 miles) at its widest point..." Scientists expect it to completely disintegrate within weeks. From the report:

> A23a calved from the Antarctic shelf in 1986 but quickly grounded in the Weddell Sea, remaining stuck on the ocean floor for over 30 years. It finally escaped in 2020 and, like other giants before it, was carried along "iceberg alley" into the South Atlantic Ocean by the powerful Antarctic Circumpolar Current. Around March, it ran aground in shallow waters off distant South Georgia island, raising fears it could disrupt large colonies of adult penguins and seals there from feeding their young. But it dislodged in late May, and moved on. [...] Iceberg calving is a natural process. But scientists say the rate at which they were being lost from Antarctica is increasing, probably because of human induced climate change.



[1] https://www.theguardian.com/environment/2025/sep/02/worlds-biggest-iceberg-crumbles-apart