World’s largest iceberg calved in 1986 – Now it’s doing this!


Iceberg A23a weighs nearly a trillion metric tonnes. Known as A23a, is roughly 1,500 square miles — about three times the size of New York City – and it just started moving north.

The massive block of ice, which was once home to a Soviet research station, originally broke off from the Filchner-Ronne Ice Shelf in West Antarctica in 1986. It’s been stranded in the Waddell Sea since its base became stuck on the ocean floor.

Now the nearly trillion metric ton chunk is quickly drifting past the northern tip of the Antarctic Peninsula, fueled by strong winds and ocean currents, satellite images show.

Not anymore.

Key points:

  • Iceberg A23a weighs nearly a trillion metric tonnes and takes up 4,000 square km
  • It will likely be launched into the Antarctic Circumpolar Current
  • It’s possible A23a could again become grounded at South Georgia island