One of the oldest icebergs in the world is about to collide with a remote British island. It is a wildlife refuge, and the enormous ice structure, one of the largest in existence, threatens to alter its ecosystem.
This giant, named “A23a,” is currently 280 km away from the British territory of South Georgia. This site is home to seabirds, elephant seals, fur seals, king penguins, and emperor penguins.
The behavior of icebergs is unpredictable, and that’s why scientists are not entirely sure when it might collide with the island or if it will break apart before impact. What consequences could it bring.
One of the oldest icebergs: how it formed
How this iceberg formed.
A23a, one of the oldest icebergs in the world and the largest, is twice the size of Greater London and weighs almost a trillion tons.
It broke off from the Filchner Ice Shelf in Antarctica in 1986 and then got stuck on the seabed for nearly 30 years.
After breaking free in 2020, it surprised scientific observers by getting trapped in an oceanic vortex, a phenomenon that keeps objects spinning in place.
In December, A23a broke free and has been moving through what ecologists call the “iceberg alley,” located between the Antarctic continent and the Joinville Island group.
Now, scientific predictions confirm that its journey will follow the Antarctic Circumpolar Current towards the Southern Ocean, leading it directly to South Georgia.
What A23a, the largest iceberg, is like
A23a measured 3900 square kilometers when it first broke off. However, as it travels through warmer waters north of Antarctica, it will start to melt, shedding pieces of ice.
Even though it will be smaller, the iceberg will still have a significant impact if it collides with the island. Its ice cliffs are up to 400 meters high, and recent NASA satellite images show that the massive iceberg is visible even from space.
While the exact extent of the damage cannot be determined, it would be severe. In 2004, a smaller iceberg, A38, collided with the location and caused penguin chicks and seal pups to starve on the beaches. Their routes to food were blocked by huge ice chunks.
Does it have to do with climate change?
What an iceberg is and how it forms.
The UN General Assembly declared 2025 as the year of the glacier, and World Glacier Day will be celebrated on March 21. Given that glaciers are threatened by melting due to the increase in ocean temperatures and air, we are likely to see more giant icebergs in the future.
However, A23a formed long before the recent years of extreme overheating. Therefore, climate change cannot be blamed for its formation or why it is moving now.
Nevertheless, locals report that icebergs pose an increasingly significant threat.
The largest iceberg in the world is in the ocean
In late 2016, scientists detected a crack in the Larsen C Ice Shelf in the West Antarctic Peninsula, which led to the detachment of the A-68 iceberg in July 2017.
This iceberg, more than twice the size of Luxembourg and 235 meters thick, embarked on a 3 and a half year odyssey to a remote island in the Southern Ocean.
The detachment of A-68 exposed the seabed, transforming the habitat and creating unique conditions for marine life.
During its transient life, A-68 acted as a frozen lifeboat for various species. Scientists have tracked its impact, revealing how giant icebergs influence the surrounding ocean.
Do you already know our YouTube channel? Subscribe now!
