The World’s Biggest Antarctic Iceberg A23a is on the Move After 30 Years

(CTN News) – The largest iceberg in the world is finally breaking free of the ocean floor after sitting there for over 30 years.

It became an ice island in the Weddell Sea shortly after calving in 1986 off the Antarctic coast; the name is A23a.

Its area is about double Greater London’s, at nearly 4,000 sq km (1,500 sq miles).

The berg has been rapidly migrating for the last 12 months, and it is now about to burst its seal outside of Antarctic waters.

It’s not merely the breadth of A23a that makes it a genuine behemoth.

This sheet of ice is around 1,312 feet thick, or 400 meters thick. As an example, the highest European skyscraper, the London Shard, is just 310 meters tall.

A23a was a berg that broke off from the Filchner Ice Shelf on the White Continent.

Its hosting of a Soviet research station at the time is indicative of how long ago it calved.

For fear of losing it, Moscow sent an expedition to empty the Druzhnaya 1 base of its equipment. The tabular berg, however, was fast fastened to the bottom-muds of the Weddell Sea by its deep keel as it sailed away from the coast.

So, why is A23a changing hands today, some 40 years later?

British Antarctic Survey remote sensing specialist Dr. Andrew Fleming stated, “I asked a couple of colleagues about this, wondering if there was any possible change in shelf water temperatures that might have provoked it, but the consensus is the time had just come.” He cited this development.

It had been on the ground since 1986, but its diminutive size meant it would ultimately lose its grip and begin to move. It was in 2020 when I noticed the first movement.

A23a is currently crossing the northern edge of the Antarctic Peninsula after putting on quite a show in the past few months, propelled by winds and currents.

Iceberg Alley Beckons: A23a’s Path Towards the South Atlantic

The Antarctic Circumpolar Current is a known “iceberg alley” that would likely expel A23a and send it hurtling towards the South Atlantic, as happens to the majority of icebergs from the Weddell sector.

In 1916, when his ship, the Endurance, was crushed by crushing sea ice, renowned explorer Sir Ernest Shackleton managed to flee Antarctica by utilizing this very water movement and the associated westerlies.

Shackleton directed his lifeboat toward South Georgia, an island where large tabular bergs may often be seen lying offshore. The blocks’ keels make them prone to get stuck on the shallow continental shelf of the British Overseas Territory.

No matter how large a berg is, it will eventually melt and disappear.

The scientists will be keeping a careful eye on A23a’s development.

It might disrupt the breeding season for millions of seabirds, penguins, and seals if it touches down at South Georgia. The enormous size of A23a poses a threat to the animal’s ability to feed their offspring because it could interfere with their regular eating patterns.

However, it is incorrect to view icebergs as only potential hazards, like the Titanic and everything. In recent years, their significance to the ecosystem as a whole has come to light.

The mineral dust that was embedded in the ice when these massive bergs were glaciers scratching against the Antarctic rock bed is being released as they melt. The tiny creatures that make up the ocean’s food web get their nourishment from this dust.

“In many ways these icebergs are life-giving; they are the origin point for a lot of biological activity,” said Dr. Catherine Walker of the Woods Hole Oceanographic Institution, who was born in the same year as A23a. “I identify with it; it’s always been there for me.”