According to the British Antarctic Survey, an iceberg that has been stuck for over 30 years is now floating away from Antarctic waters, making it one of the biggest icebergs in the world.

In 1986, a portion of the Antarctic’s Filchner Ice Shelf, referred to as A23a, broke off and became wedged on the ocean floor in the Weddell Sea. It has remained in this location for several years.

Currently, the iceberg, which weighs approximately one trillion metric tonnes, is moving at a rapid pace past the northern end of the Antarctic Peninsula. This movement is being assisted by strong winds and currents, as shown in recent satellite images.

The iceberg covers an area of approximately 4,000 sq km (1,500 square miles), making it three times larger than New York City and more than twice the size of Greater London.

According to glaciologist Oliver Marsh from the British Antarctic Survey, it is uncommon to witness such a large moving iceberg. As a result, researchers are closely monitoring its path.

As it gains momentum, the massive iceberg is likely to be carried into the Antarctic Circumpolar Current. This will guide it towards the Southern Ocean, following a route known as “iceberg alley” where other similar icebergs can be seen floating in the dark waters. The reason for its sudden movement is currently unknown.

According to Marsh, A23a may have gradually become thinner and gained slight buoyancy, allowing it to rise from the bottom of the ocean and be carried by ocean currents. A23a is also one of the oldest icebergs in the world.

On Friday, BBC was informed by Andrew Fleming, a specialist in remote sensing from the British Antarctic Survey, that the iceberg has been in motion for the last year and currently seems to be accelerating.

I inquired with a few coworkers about this matter, curious if there had been any fluctuations in shelf water temperatures that could have caused it. However, the general agreement is that it was simply a matter of timing,” Fleming explained to the BBC.

Fleming reported observing the iceberg’s movement in 2020. According to the British Antarctic Survey, it has since become dislodged and is currently being carried by ocean currents towards the sub-Antarctic region of South Georgia.

A potential scenario is that A23a may once again be stranded at South Georgia Island. This could potentially harm the wildlife in Antarctica, as millions of seals, penguins, and seabirds rely on the island for breeding and food. The large size of A23a could potentially block their access to these resources.

In the year 2020, there was concern over a large iceberg named A68 potentially causing harm to South Georgia by damaging the sea floor and disrupting food sources for marine life. Fortunately, this disaster was avoided when the iceberg split into smaller pieces, which could also happen to A23a in the future.

According to Marsh, a large iceberg in the Southern Ocean has the ability to endure for a significant period of time despite the warmer temperatures. This could result in the iceberg drifting towards South Africa and causing disruptions to shipping.

as sources

Based on information from Reuters and Associated Press

Source: theguardian.com