The world's largest iceberg is on course to collide with the island of South Georgia, a key haven for wildlife in the south Atlantic Ocean, scientists say. They add it could have a grave impact on the ecology and economy of the island.
The giant iceberg carved off the Larsen C ice shelf on the eastern Antarctic peninsula in 2017. Named by scientists as A68a, it has since drifted toward South Georgia, a remote British island.
Satellite images show the iceberg is still largely intact. Some 150 kilometers long and 48 kilometers wide, it is traveling at one kilometer per hour and is on course to hit South Georgia in around 30 days.
Its shallow depth of 200 meters means it could drift very close to the island and ground just offshore. South Georgia is home to huge colonies of penguins and seals. Their feeding grounds could be blocked just as breeding season gets under way, says scientist Geraint Tarling of the British Antarctic Survey.
"That means they have to go a lot further, they have to go around the iceberg, or to actually go further to find sources of food. And that time is quite critical at this particular period of their life cycle. They have to get back to their chicks and pups in short amounts of time so that they don't starve in the interim," Tarling told VOA.
The grounding of the iceberg would disturb the soft sediment on the seabed, polluting the surrounding seas, ecologists say. As the iceberg melts, it also would release large amounts of fresh water into the ocean, potentially affecting the krill populations that are a staple food for the island's wildlife.
Tarling says the iceberg could stick around for a decade and change the entire ecosystem. "These are globally significant populations of these species. If these species fail in this particular area, then the numbers globally are going to go down quite dramatically."
Iceberg carving in Antarctica is a natural process – but it's modifying with climate change.
"What we're seeing with models and some observations now is the rate at which this is happening is increasing. And so, this might become more of a usual thing into the future," Tarling told VOA.
The iceberg also could damage South Georgia's valuable fishing industry. Licenses are sold to catch Patagonian sawtooth fish and krill, which supply omega-3 oils for nutrition supplements.
The hope is that changing weather patterns could yet divert the iceberg into the open ocean, where it would eventually break up and melt.