World's biggest iceberg A23a drifting towards penguin-packed island

The world's largest iceberg, a 40-meter-high wall of ice larger than the Australian Capital Territory, is steadily drifting towards a remote British island near Antarctica, six weeks after breaking free from its seabed anchor point. This ice block, named A23a, is described as a colossal iceberg weighing nearly a trillion tons and could potentially collide with South Georgia Island, after which it will either become grounded or be guided around the island by ocean currents.

If the iceberg becomes grounded, it could make it difficult for penguin parents on the island to feed their chicks, leading to some of the young starving. While scientists and researchers are not currently concerned about the potential damage the iceberg might cause, some are excited about the natural processes involving A23a, which they believe are occurring more frequently due to human-caused climate change.

Andrew Meijers, a physical oceanographer at the British Antarctic Survey, stated that iceberg calving is normal, but it is happening more frequently as climate change causes more freshwater to flow into the ocean. Mr. Meijers observed the iceberg up close in December 2023 when it first drifted past the research vessel RRS Sir David Attenborough.

He noted that for every part of the iceberg visible above the water, there are more than ten times as much ice below the surface. Mr. Meijers also stated that the iceberg is slowly moving at a speed of one meter every three to seven seconds. Over the next two to four weeks, the iceberg will approach South Georgia Island, where it may become grounded in shallow waters near the British territory, or it may be diverted around it.

Eventually, A23a will break apart and melt like other icebergs, but researchers are now more concerned about the potential impact it may have on the penguin summer breeding cycle. This iceberg initially calved from Antarctica in 1986 but was trapped for decades in a congested area of sea ice. On December 13th of last year, the British Antarctic Survey announced that the colossal iceberg had broken free from its latest seabed anchor point and was drifting in the Southern Ocean.