Mega iceberg A-68A dumped 168 billion tons of fresh water into the ocean

Scientists are wondering how all that water might impact the wildlife haven of South Georgia Island.

Amanda Kooser
Freelance writer Amanda C. Kooser covers gadgets and tech news with a twist for CNET. When not wallowing in weird gear and iPad apps for cats, she can be found tinkering with her 1956 DeSoto.
Amanda Kooser
2 min read
Satellite image showing the A-68A iceberg and pieces that have broken off

This 2021 satellite image shows the main A-68A iceberg and the chunks breaking off, including the large piece called A-68G.

European Space Agency

The saga of iceberg A-68A was riveting. It was the main part of the A-68 iceberg, which broke off the Larsen C ice shelf in Antarctica in 2017. Three years later it had floated into warmer waters and was threatening South Georgia Island, an important haven for penguins, seals and other wildlife. Fortunately, the jumbo berg broke up, but its impact may still be felt.

In a statement Thursday, the European Space Agency said the iceberg "released a colossal 152 billion tonnes of fresh water close to the island, potentially having a profound effect on the island's marine life." That works out to about 168 billion US tons. The University of Leeds in the UK related this to 20 times the amount of water in Loch Ness or 61 million Olympic-size swimming pools.

The original A-68 was one of the largest icebergs on record. It "calved" as part of a normal, natural process in which pieces break away. A research team used satellite data and imagery to measure the amount of water released by A-68A and published the findings in the journal Remote Sensing of Environment

The big berg also released a lot of nutrients into the ocean along with the fresh water. Lead author Anne Braakmann-Folgmann at the University of Leeds said, "This is a huge amount of melt water, and the next thing we want to learn is whether it had a positive or negative impact on the ecosystem around South Georgia."

Graphic visualizing how much water was released by iceberg A-68A into the ocean compared with the island of Manhattan.
Enlarge Image
Graphic visualizing how much water was released by iceberg A-68A into the ocean compared with the island of Manhattan.

This graphic visualizes how much water was released by A-68A into the ocean as compared to the height of landmarks like the Eiffel Tower and Mount Fuji and the size of Manhattan.

CPOM/ESA/Google basemap

In late 2020, British Antarctic Survey ecologist Geraint Tarling said the dust contained in the iceberg could fertilize ocean plankton in water, which in turn could provide a boost to the local food chain.

According to BAS, South Georgia is an important location for seals, threatened bird species, fish and migrating whales. While the great danger of A68-A bogging down was avoided, it now opens up new questions about how the berg's water and nutrients might affect the delicate ecosystem and the animals that live there. It'll take time to learn the answers.