This NASA Earth Observatory image shows iceberg A68 after its split from the Antarctic ice shelf in 2017.


NASA Earth Observatory/Joshua Stevens/Landsat data from the USGS

Iceberg A68 was an eye-popping behemoth when it broke off of an Antarctic ice shelf in 2017. A huge piece of that iceberg (a chunk known as A68a) is on a disquieting path toward the wildlife haven of South Georgia Island in the southern Atlantic Ocean.

In a statement on Wednesday, the British Antarctic Survey (BAS) warned the iceberg could disrupt the local wildlife if it becomes grounded near the island. Ocean-foraging penguins and seals could be particularly vulnerable.

“Ecosystems can and will bounce back, of course, but there’s a danger here that if this iceberg gets stuck, it could be there for 10 years,” BAS ecologist Geraint Tarling said. “An iceberg has massive implications for where land-based predators might be able to forage.”

Researchers are concerned penguins and seals might have to detour around the huge iceberg to find food while raising their young. 

There could be a silver lining if the iceberg sticks to the open ocean. “It carries enormous quantities of dust that fertilize the ocean plankton in the water that cascades up the food chain,” Tarling said. 

Satellites have been tracking A68 since it broke off and current data shows it’s located 250 miles (400 kilometers) from the island and is making a beeline toward it. It’s still possible the iceberg’s path could change, carrying it past the island. BAS has requested more data from the European Space Agency’s Sentinel-1 spacecraft. 

The iceberg was one of the largest on record when it first calved, and A68a remains a monstrous size. BAS remote-sensing manager Andrew Fleming described it as “spectacular.” “The idea that it is still in one large piece is actually remarkable, particularly given the huge fractures you see running through it in the radar imagery,” Fleming said.

If the iceberg finally makes it to warmer waters, its fate would be sealed. It would eventually break up and melt away. If not, it could mean hard times for some of the animal residents of South Georgia Island.

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