In 1986, the iceberg broke off and soon ran aground in the Weddel Sea between Queen Maud Land and the Antarctic Peninsula. Since then, the iceberg, named A23a, has mostly remained lying around.

But in 2020, it began to weaken and now scientists can say that it has broken free from the seabed. Now the ice mass is located near the northern tip of the Antarctic Peninsula.

It will probably follow the Southern Ocean Current into the South Atlantic via a route called “iceberg alley” because of the large number of icebergs that end up here.

Nine times bigger than Oslo

This iceberg is almost nine times the size of the Oslo area. It weighs almost three trillion tons and is more than 400 meters thick.

There may be no particular reason why A23a is moving at this time, experts say.

– Over time, it may have become slightly thinner and gained greater buoyancy, allowing it to lift off the sea floor and be carried by ocean currents, says glaciologist Oliver Marsh.

Can cause problems

It is not impossible that the iceberg could run aground again on the South Georgia Islands in the South Atlantic.

This could be a major problem for the rich animal life on the islands, as access to food at sea could be reduced for millions of seals, penguins and birds. Something similar almost happened in 2020 with the A68 iceberg, but this was averted when the iceberg broke up.

– But an iceberg this size has the potential to last quite a long time in the Southern Ocean, Marsh said.

According to glaciologists, this could reach South Africa, which could pose problems for shipping.