The largest iceberg in the world accelerates its movement
An iceberg that covers almost 1,500 square miles, roughly three times the size of New York City, is moving into the open ocean. Here’s where it’s headed.
The melting of icebergs is nothing new, but when an especially large section of the polar ice shelf breaks loose it can generate quite the stir given the consequences that it could have. Such is the case now, with the focus curretnly on a particular one called A23a, the largest in the world.
The large mass of ice has moved from the Weddell Sea out into the waters of the Atlantic Ocean, it weighs one trillion tons and it has a surface area of 1,500 square miles. To put that last figure into context, it is about three times the size of New York City and slightly bigger than O’ahu Island in Hawaii. “It stretches as far as the eye can see,” said Chief Scientist aboard the RRS Sir David Attenborough Dr Andrew Meijers.
To all this, we must add its thickness which is estimated to be as much as 1,300 feet in some sections. That is about the size of the Empire State Building which is 1,250 feet tall. According to the British Antarctic Survey website, this iceberg calved off from the Filchner Ice Shelf in 1986 but was grounded in the seabed nearby and has been stuck there until now. In late November the mammoth piece of ice broke free and it is likely to be swepted along by an Antarctic Circumpolar Current into the southern Atlantic Ocean ‘iceberg alley’ towards the South Georgia Islands.
On these sub-Antarctic islands, where 75% of its surface is covered by snow, you can find animals such as elephant seals, penguins and seals, as well as different types of seabirds, including albatrosses, petrels, cormorants, seagulls. or sea terns. The population of the islands barely reaches 1,000 inhabitants.
The principal investigator of the BIOPOLE program and scientific leader of ecosystems at BAS, Geraint Tarling, explained that the calving of icebergs is “part of the natural life cycle” of glaciers. Polar ecosystems play a crucial role in regulating the balance of carbon and nutrients in the world’s oceans and are impacted by melting icebergs in numerous ways.”
Possible benefits of detachment
Although a possible future grounding near the islands would cause devastating consequences for the fauna and flora there, blocking access to migrating ocean wildlife, the experts point out that icebergs end up melting, leaving benefits for the environment in their wake with the consequent release of mineral sediments within, which would serve as a source of nutrients for organisms.
This is how biogeochemist Laura Taylor explained it. “We know that these giant icebergs can provide nutrients to the waters they pass through, creating thriving ecosystems in otherwise less productive areas. What we don’t know is what difference particular icebergs, their scale, and their origins can make to that process.”