One of the world’s largest icebergs is moving for the first time in thirty years, scientists announced Friday, November 24. At nearly 4,000 square kilometers, Antarctic iceberg A23a is about three times the size of New York City.
Since breaking away from the Filchner-Ronne Ice Shelf in West Antarctica in 1986, the iceberg that once housed a Soviet research station has remained largely stuck, its submerged portion coming to rest at the bottom of the Weddell Sea.
However, recent satellite images have shown that the nearly billion-ton iceberg is now drifting quickly past the northern tip of the Antarctic Peninsula, pushed by strong winds and currents.
“Iceberg Corridor”
It’s rare for an iceberg of this size to move, said Oliver Marsh, a glaciologist with the British Antarctic Survey. As it gains strength, the colossal iceberg will likely be thrown into the Antarctic Circumpolar Current, which will then carry it toward the Southern Ocean on a trajectory known as the “iceberg corridor,” where other icebergs of its kind float in the dark waters.
The reason for his trip is currently unknown. “Over time it probably became a little thinner and gained that little extra buoyancy that allowed it to rise from the seafloor and be pushed by the ocean currents,” said Oliver Marsh. A23a is also one of the oldest icebergs in the world.
It is possible that it may run aground on the island of South Georgia, located in the southern Atlantic, which could pose a problem for Antarctic flora and fauna. Millions of seals, penguins and seabirds breed on the island and forage in the surrounding waters.
In 2020, another huge iceberg, A68, threatened to collide with South Georgia Island but ultimately broke into smaller pieces beforehand. A fate that A23a could also experience.