World’s largest iceberg nears South Georgia, threatening baby penguins

Paris: The world's largest iceberg, measuring over twice the size of London, is drifting towards South Georgia, a remote island that serves as a crucial breeding ground for penguins and seals. Scientists are concerned that the massive block of ice could run aground, potentially threatening the island’s wildlife.

The iceberg, known as A23a, broke off from Antarctica’s ice shelf in 1986. Spanning roughly 3,500 square kilometres (1,550 square miles), it has been on a slow journey through the Southern Ocean. Unlike other large icebergs, A23a has remained mostly intact, resisting fragmentation as it moves northward.  

Andrew Meijers, a physical oceanographer at the British Antarctic Survey, explained, “It’s just like this white wall. It’s very sort of 'Game of Thrones'-esque, actually.” He described the iceberg as “a huge white cliff, 40 or 50 metres high, that stretches from horizon to horizon.”  

Possible collision with south Georgia 

Satellite imagery suggests that A23a may reach South Georgia’s shallow continental shelf within two to four weeks, although its exact path remains uncertain.  

“It could avoid the shelf and get carried into open water beyond South Georgia,” Meijers said.

“Or it could strike the sloping bottom and get stuck for months or break up into pieces.”  

If the iceberg grounds itself near South Georgia, it could disrupt the feeding patterns of seals and penguins raising their young on the island. “Icebergs have grounded there in the past, and that has caused significant mortality to penguin chicks and seal pups,” Meijers added.  

Impact on wildlife

South Georgia’s wildlife, particularly penguins and seals, is already facing challenges due to an outbreak of bird flu. The arrival of A23a could worsen the situation.  

“If the iceberg parks there, it’ll either block physically where they feed from, or they’ll have to go around it,” Meijers explained. “That burns a huge amount of extra energy for them, so that’s less energy for the pups and chicks, which causes increased mortality.”  

The iceberg's potential collision with the island could also litter the ocean with hazardous chunks of ice, making navigation difficult for fishermen.  

Hope for a detour  

Not all scientists believe a collision is inevitable. Raul Cordero from Chile’s University of Santiago is optimistic that the iceberg will avoid South Georgia.

“The island acts as an obstacle for ocean currents and therefore usually diverts the water long before it reaches the island,” he said.  

However, Meijers noted that the iceberg’s current trajectory appears to be heading straight towards the island.  

A natural phenomenon with global implications  

While icebergs are natural occurrences, the rate of ice loss from Antarctica is increasing due to climate change, Meijers said.  

As A23a melts, it could release nutrients into the water, encouraging the growth of phytoplankton, which feeds whales and other species. This phenomenon also provides scientists with an opportunity to study how such blooms absorb carbon dioxide from the atmosphere.  

Despite the potential benefits, the immediate threat to South Georgia’s wildlife remains a significant concern.

“It would be fairly tragic, but it’s not unprecedented,” Meijers concluded.

AFP