The largest iceberg in the world breaks apart

For Antarctic researchers, iceberg A23a is an old friend. The enormous ice massif had already broken off off the coast of the South Pole 37 years ago, but froze at the bottom of the Weddell Sea on its way north. After the ice floe (with an area twice the size of the canton of St. Gallen) broke loose again last year, it drifted at high speed into the South Atlantic Ocean.

Now the crew of an expedition ship has reached the ice behemoth and reported huge caverns and arches carved into the frozen walls by erosion.

Conservationist and photographer Richard Sidey is also on board the ship. He posted a spectacular photo of A23a on Instagram on Monday and wrote: “This morning I photographed A23a, the largest iceberg in the world! Weighing almost a trillion tons, this monster mountain is up to 400 meters thick and has an area of ​​3,900 square kilometers. Just incredibly big.”

“It was dramatic and beautiful to photograph,” Sidey told the BBC. “The mountain is incredibly big. I don’t think we can imagine how big he is. It’s definitely too big to photograph. It extends in both directions as far as you can see.”

“We saw waves about three to four meters high hitting the iceberg,” said expedition leader Ian Strachan, describing the encounter with the monster. “They caused ice cascades. A constant state of erosion.”

The further the iceberg gets from the South Pole, the more it will break off due to warmer air and water. A23a is currently drifting along the Antarctic Circumpolar Current, driven by westerly winds, 600 kilometers south of the South Orkney Islands, the BBC reports, citing information from the expedition team.

The big question is: how long can A23a survive? Even experts do not want to commit to this. In fact, the process can take years, as another example shows: Another iceberg observed by scientists is D28.

According to information, it is located in the South Atlantic Ocean, about 200 kilometers north of the archipelago of South Georgia (about 1,500 kilometers east of Cape Horn). Although the D28 has already lost a third of its mass, it is still compact since breaking off the ice shelf in 2019.