The trillion-ton iceberg got trapped above a whirling vortex of ocean current.
About 375 miles northeast of the Antarctic Peninsula, near the South Orkney Islands, a colossal iceberg weighing one trillion tons is slowly spinning in the ocean like a giant top. This massive ice block, the world’s largest iceberg, is known as “A23a.” In February 2024, the British Antarctic Survey (BAS) announced that A23a had entered its “spinning era” and released footage of the iceberg rotating to Kylie Minogue’s “Spinning Around,” adding a touch of humor to the otherwise awe-inspiring event. The mesmerizing motion of this city-sized berg has captured the internet’s attention, thanks to its fascinating history.
Currently, the berg is “maintaining a chill 15-degree rotation per day,” as the BAS wrote on X. However, for the past three decades, the iceberg was still perfectly positioned at the Weddell Sea's bottom. It was not until 2020 that A23a finally detached, broke free from the seafloor, and started moving towards the Southern Ocean, per The New York Times. However, as it turned out, the iceberg never moved away. It stayed there for what seemed like a slow-motion dance session. It is now spinning on the other side of the South Scotia Ridge.
Surprisingly, the A23a mega iceberg is very much still with us and has postponed its expected melty journey north…
— British Antarctic Survey 🐧 (@BAS_News) August 4, 2024
This Cornwall-sized piece of ice is now just spinning in an ocean vortex near the South Orkney Islands, maintaining a chill 15° rotation per day🍹 https://t.co/30WWXlQXPJ pic.twitter.com/wj0rStxMlh
BAS used the imagery captured by instruments aboard NASA satellites between December 2023 to February 2024 to demonstrate the consistent rotation of the iceberg. But it's spinning around is not for no reason. This is a scientific phenomenon known as a “Taylor column.”
The #A23a megaberg is in its spinning era 💃💞
— British Antarctic Survey 🐧 (@BAS_News) February 14, 2024
These dance moves down #IcebergAlley are part of the iceberg’s long, melty journey into warmer waters.
Don’t be deceived by your screen size - this is the biggest iceberg in the world, around the size of Cornwall or Rhode Island! pic.twitter.com/XF5UWg4NBz
IFL Science explains Taylor’s Column as when a rotating cylinder of water forms when an ocean current meets a seamount. In this case, it is the Antarctic Circumpolar Current, that BBC describes as “a juggernaut that moves a hundred times as much water around the globe as all Earth's rivers combined.” This vigorous current meets a seamount or an underwater mountain in the Scotia Sea to trigger this twirling motion of A23a.
“It’s basically just sitting there, spinning around and it will very slowly melt as long as it stays there,” said Alex Brearley, a physical oceanographer and head of the Open Oceans research group at the British Antarctic Survey, per The New York Times. “What we don’t know is how quickly it will actually come out of this.”
Usually, after detaching from the seabed, most icebergs drift into the warmer waters, and after a warm bath, they eventually melt. But the fate of this gigantic iceberg is still uncertain. Different experts have different opinions as to what awaits it. For instance, Christopher A. Shuman, a glaciologist and research professor at the University of Maryland, Baltimore County, told The New York Times that A23a would eventually move toward the island of South Georgia in the South Atlantic and melt. Whereas, polar expert Professor Mark Brandon believes that “Usually you think of icebergs as being transient things; they fragment and melt away. But not this one,” per BBC. According to Mark, “A23a is the iceberg that just refuses to die.”