The world’s largest iceberg – more than twice the size of London – could be headed for a remote island where a scientist warns it disrupts feeding for baby penguins and seals.
The massive wall of ice is slowly moving from Antarctica on a potential collision course with South Georgia, an important wildlife breeding ground in the South Atlantic.
Satellite imagery suggested that unlike previous “megabergs” this rogue was not falling into smaller fragments as it tore through the Southern Ocean, Andrew Meijers, a physical oceanographer with the British Antarctic Survey, told AFP on Friday.
He said it was difficult to predict its exact course, but prevailing currents suggested Colossus would reach the shallow continental shelf around South Georgia in two to four weeks.
But what might happen next is anyone’s guess, he said.
It can escape the shelf and take to the open waters beyond South Georgia, a British overseas territory (about 1,400 kilometers (870 mi) east of the Falkland Islands).
Or it could strike the bottom of the slope and become stuck for months or break into pieces.
Meijers said this scenario could seriously threaten seals and penguins trying to feed and raise their young in the city.
“Icebergs have grounded there in the past and have caused significant mortality for penguin chicks and seal pups,” he said.
‘white wall’
The world’s largest and oldest iceberg, approximately 3,500 square kilometers (1,550 sq mi), known as A23A, was calved from the Antarctic shelf in 1986.
It remained stuck for more than 30 years before finally being freed in 2020, its lengthy journey north occasionally delayed by ocean forces that kept it spinning in place.
Meijers – who encountered the iceberg while leading a scientific mission in late 2023 – described “a huge white rock, 40 or 50 meters high, that stretches from horizon to horizon”.
“It’s like this white wall. It’s very Game of Thrones-esque, actually,” he said, referring to the dark fantasy series.
A23a followed the same route as previous large-scale icebergs, passing along the east side of the Antarctic Peninsula through the Weddell Sea, known as “Iceberg Alley”.
Weighing in at a little under a trillion tons, this monster block of freshwater was being whipped around by the world’s most powerful ocean “jet stream” – the Antarctic Circumpolar Current.
Raul Cordero of the University of Santiago in Chile, who is also part of the National Antarctic Research Committee, said he was confident the iceberg would bypass South Georgia.
“The island acts as a barrier to ocean currents and therefore usually removes water long before it reaches the island,” he said.
“The iceberg is moved by that water flow, so the chance of hitting it is not as high,” although chunks could, he said.
Another scientist, glaciologist Soledad Tiranti currently on an Argentine exploration trip in the Antarctic, said that icebergs like A23A “are so deep that they usually get stuck before reaching an island or mainland”.
icy barrier
It’s summer in South Georgia and resident penguins and seals along its southern coast are foraging in the frosty waters to bring back food to fatten their young.
“If the iceberg parks there, it will either physically block where they feed, or they will have to go around it,” Meijers said.
“It burns a huge amount of extra energy for them, so it’s less energy for the pups and chicks, which causes increased mortality.”
The seal and penguin populations on South Georgia are already having a “bad season” with the bird flu outbreak “and that (iceberg) will make it significantly worse,” he said.
As A23A eventually melts, it may seed the water with nutrients that encourage phytoplankton growth, feeding whales and other species, and allowing scientists to study how such blooms occur. How carbon dioxide is absorbed from the atmosphere.
While icebergs are natural phenomena, Meijers said the rate at which they were being lost from Antarctica was increasing, possibly due to human-induced climate change.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)