Satellite imagery and reports from the British Antarctic Survey

40-Meter-Tall, 1 Trillion Tonne Iceberg A23a Threatens Penguins and Seals on South Georgia

Jan 23, 2025, 07:30 PM

The world's largest iceberg, known as A23a, is drifting towards South Georgia, a remote British island in the South Atlantic Ocean. This colossal iceberg, which spans 3,500 square kilometers, is 40 meters tall and weighs nearly one trillion tonnes, poses a potential threat to the island's wildlife, particularly to the millions of penguins and seals that inhabit the area. A23a, which broke off from Antarctica's Filchner-Ronne Ice Shelf in 1986, has been on the move since becoming dislodged from the sea floor in December 2024. Moving at a glacial pace of one meter every three to seven seconds, the iceberg is expected to approach South Georgia in the next two to four weeks. Its approach could block access to feeding grounds for the island's wildlife, potentially leading to increased mortality rates among young penguins and seals during their summer breeding cycle. While researchers are not overly concerned about major harm, they note that the event is part of a natural process that is occurring more frequently due to human-caused climate change.