The Spectacular Erosion of the World's Largest Iceberg

The Magnificent A23a Iceberg

Erosion has chipped dramatic features into the iceberg as it floats through the ocean away from Antarctica, spectacular new photos show. Erosion has carved huge arches and cavernous hollows into the world’s largest iceberg as it floats through the ocean away from Antarctica, spectacular new photos show.

A23a is currently the largest iceberg in the world.

The images were captured by photographers aboard a vessel run by the company EYOS Expeditions, which has been cruising along a section of the A23a iceberg. The photos reveal the vast scale of the iceberg — which is more than twice the size of the UK capital, London — as it stretches off into the distance.

The A23a iceberg is being gradually eroded as it moves further north of Antarctica and encounters milder air and warmer ocean temperatures. The expedition team witnessed chunks of the iceberg break off into the sea, an EYOS Expeditions spokesman told CNN.

A23a is on the move after nearly three decades of being grounded on the seafloor in Antarctica. The huge mass of ice broke away from the Filchner-Ronne ice shelf in 1986, calved and grounded on the Antarctic’s Weddell Sea floor almost immediately. A23a is currently the largest iceberg in the world.

The Enormous Scale and Carved Features

The images show the deep surface cracks, as well as hollowed out caves, carved into the iceberg. Huge caverns and long jagged cracks can be seen in the iceberg. The iceberg is about 400 meters (1,312 feet) thick, and almost 4,000 square kilometers (1,544 square miles) in area. That’s more than three times the size of Los Angeles.

Huge caverns and long jagged cracks can be seen in the iceberg.

A satellite imagery of the world's largest iceberg, named A23a, seen in Antarctica, November 15, 2023. Courtesy of European Union/Copernicus Sentinel-3/Handout via REUTERS THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. MANDATORY CREDIT.

A satellite imagery of the world's largest iceberg, named A23a, seen in Antarctica, November 15, 2023. Courtesy of European Union/Copernicus Sentinel-3/Handout via REUTERS THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. MANDATORY CREDIT.

Implications of the Erosion

The world’s biggest iceberg is on the move. A23a has held the 'largest current iceberg' title several times since the 1980s, occasionally being surpassed by larger but shorter-lived icebergs, including A68 in 2017 and A76 in 2021. The enormous iceberg will eventually disappear completely.

Scientists have said that, while this particular iceberg likely broke away as part of the natural growth cycle of the ice shelf, climate change is driving worrying changes in this vast, isolated continent with potentially devastating consequences for global sea level rise. Last February, Antarctic sea ice reached its lowest extent since records began, at 691,000 square miles.