World

Meet A-76, the world’s largest Iceberg

An enormous iceberg has calved from the western side of the Ronne Ice Shelf, lying in the Weddell Sea, in Antarctica.

Published

May 20, 2021

In recent images captured by the Copernicus Sentinel-1 mission, the iceberg is slightly larger than the Spanish island of Majorca, or a little bigger than the state of Rhode Island. Image courtesy of ESA, Public Domain.

An enormous iceberg has calved from the western side of the Ronne Ice Shelf, lying in the Weddell Sea, in Antarctica. The iceberg, dubbed A-76, measures around 4320 sq km (1,668 square miles) in size – currently making it the largest berg in the world.

While the iceberg’s official name does not reflect its enormous size, the European Space Agency (ESA) says it has snatched first place from the A-23A iceberg (approximately 3880 sq km in size) which is also located in the Weddell Sea.

The naming of icebergs is based on science, according to CNN. The ESA explains that icebergs are traditionally named from the Antarctic quadrant in which they were originally sighted, then a sequential number, then, if the iceberg breaks, a sequential letter.

Antarctica gives birth to world’s largest iceberg

The iceberg has been described as either an ironing board or a very large finger. It is roughly 105 miles (170 kilometers) long and 15 miles (25 kilometers) wide, and was spotted by the British Antarctic Survey and confirmed from the US National Ice Center using Copernicus Sentinel-1 imagery.

The Sentinel-1 mission consists of two polar-orbiting satellites that rely on C-band synthetic aperture radar imaging, returning data regardless of whether it is day or night, allowing us year-round viewing of remote regions like Antarctica.

Despite its enormous size, A-76 will not directly create a rise in sea level as it melts, eventually. This is because the ice shelf that this iceberg calved from was already floating on water, sort of like an ice cube floating in a glass of water.

But keep in mind that Antarctica’s ice shelves help to slow the flow of glaciers and ice streams into the sea; so indirectly, the loss of parts of an ice shelf eventually contributes to rising seas, according to the National Snow and Ice Data Center (NSIDC).

However, scientists don’t think that human-induced climate change caused the calving of A-76 or its nearby predecessor, A-74.

“A76 and A74 are both just part of natural cycles on ice shelves that hadn’t calved anything big for decades,” Laura Gerrish, a researcher at the British Antarctic Survey, wrote on Twitter. “It’s important to monitor the frequency of all iceberg calving, but these are all expected for now.”

Iceberg A-74 pictured by Landsat 8 on 1 March 2021 Image: NASA Earth Observatory image by Joshua Stevens – Public Domain

In this article:Antarctica, Esa, iceberg A-76, Ronne ice shelf, Sentinel 1 mission

Written By Karen Graham

We are deeply saddened to announce the passing of our dear friend Karen Graham, who served as Editor-at-Large at Digital Journal. She was 78 years old. Karen's view of what is happening in our world was colored by her love of history and how the past influences events taking place today. Her belief in humankind's part in the care of the planet and our environment has led her to focus on the need for action in dealing with climate change. It was said by Geoffrey C. Ward, "Journalism is merely history's first draft." Everyone who writes about what is happening today is indeed, writing a small part of our history.