The world’s largest and longest-lived iceberg, A23A, is slowly breaking apart in the South Atlantic Ocean. It broke off from Antarctica’s Filchner-Ron Ice Shelf in 1986, nearly four decades ago. At the time, it covered an area of ​​3,672 square kilometers and weighed an estimated one trillion metric tons—larger than the US state of Rhode Island.

“A23A is currently breaking apart rapidly and could disappear completely within weeks,” said Andrew Meijers, an oceanographer at the British Antarctic Survey (BAS).

After breaking apart in 1986, the massive iceberg became trapped at the bottom of the Weddell Sea and spent more than three decades there. In 2020, as the ice began to melt, it resurfaced and began its journey towards the South Atlantic Ocean, pulled by Antarctic currents.

Satellite images from the European Union show that A23A is now 1,770 square kilometers, less than half its original size. Its widest point is about 60 kilometers. It is now moving at an average speed of 20 kilometers per day.

The iceberg approached South Georgia Island in March, causing concern for local penguins and seals. But in May, it began its northward journey again.

Scientists say that while icebergs break up naturally, climate change is accelerating the rate. Warmer ocean waters and strong waves are melting the iceberg from below, accelerating the breakup.

The collapse of A23A means that D15A has now become the world's largest iceberg. It is about 3,000 square kilometers in area and is located off the coast of Antarctica near the Davis Territory in Australia.