World’s biggest iceberg is caught on camera: Incredible footage shows ‘megaberg’ twice the size of Greater London as it floats out into the Southern Ocean after 30 years stuck to the seabed

Incredible footage has provided a new view of the world’s biggest iceberg as it begins its journey out into the Southern Ocean. 

The iceberg, called A23a, is around 1,540 sq miles in area – more than twice the size of Greater London (607 sq miles) – and a whopping 1,312 feet thick. 

It hit the headlines last week after it began to move, following 30 years stuck to the ocean floor. 

Now, the British Antarctic Survey (BAS) has released new video and images captured by the RRS Sir David Attenborough, showing the ‘megaberg’ stretching out into the distance beyond the research vessel. 

‘It is incredibly lucky that the iceberg’s route out of the Weddell Sea sat directly across our planned path, and that we had the right team aboard to take advantage of this opportunity,’ said Dr Andrew Meijers, Chief Scientist on RRS Sir David Attenborough and Polar Oceans Science Leader at BAS. 

Incredible footage has provided a new view of the world's biggest iceberg as it begins its journey out into the Southern Ocean

Incredible footage has provided a new view of the world’s biggest iceberg as it begins its journey out into the Southern Ocean

The iceberg, called A23a, is around 1,540 sq miles in area ¿ more than twice the size of Greater London (607 sq miles) ¿ and a whopping 1,312 feet thick

The iceberg, called A23a, is around 1,540 sq miles in area – more than twice the size of Greater London (607 sq miles) – and a whopping 1,312 feet thick

While A23a originally calved from the Filchner Ice Shelf back in 1986, it remained grounded on the seabed until last week. 

On November 24, the megaberg broke free and began moving out of the Weddell Sea sector into the Southern Ocean.

Now, the megaberg is likely to be swept along by the Antarctic Circumpolar Current into ‘iceberg alley’, according to the BAS. 

This puts it on a common iceberg trajectory towards the sub-Antarctic island of South Georgia.

This week, the RRS Sir David Attenborough happened to pass the iceberg as part of its planned route towards the Weddell Sea. 

‘We’re fortunate that navigating A23a hasn’t had an impact on the tight timings for our science mission,’ Dr Meijers said. 

‘It is amazing to see this huge berg in person – it stretches as far as the eye can see.’

The iceberg hit the headlines last week after it began to move, following 30 years stuck to the ocean floor

The British Antarctic Survey has released new video and images captured by the RRS Sir David Attenborough, showing the 'megaberg' stretching out into the distance beyond the research vessel

The British Antarctic Survey has released new video and images captured by the RRS Sir David Attenborough, showing the ‘megaberg’ stretching out into the distance beyond the research vessel

How do icebergs form? 

An iceberg is a piece of freshwater ice that has detached from a glacier and is floating in the ocean.

Icebergs form when pieces of ice break off the end of an ice shelf or a glacier that flows into a body of water.

This is called ‘calving’ and is a natural process that is responsible for ice loss at the edges of glaciers and ice sheets.

Aside from filming it, the researchers also took samples from the iceberg. 

They hope these will aid in our understanding of how climate change is affecting the Southern Ocean and the organisms that live there. 

Laura Taylor, a biogeochemist working on the mission, said: ‘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.

‘We took samples of ocean surface waters behind, immediately adjacent to, and ahead of the iceberg’s route. 

‘They should help us determine what life could form around A23a, and how this iceberg and others like it impact carbon in the ocean and its balance with the atmosphere.’

The record for the largest current iceberg changes most years, as new icebergs are calved off the Antarctic continent and subsequently break into smaller fragments.

While A23a originally calved from the Filchner Ice Shelf back in 1986, it remained grounded on the seabed until last week

While A23a originally calved from the Filchner Ice Shelf back in 1986, it remained grounded on the seabed until last week

Aside from filming it, the researchers also took samples from the iceberg. They hope these will aid in our understanding how climate change is affecting the Southern Ocean and the organisms that live there

Aside from filming it, the researchers also took samples from the iceberg. They hope these will aid in our understanding how climate change is affecting the Southern Ocean and the organisms that live there

Rising waters and air temperatures caused by global warming are triggering instabilities along the coasts of Antarctica and Greenland, accelerating melting and increasing the rates of calving. 

The former record holder was A76, which detached from an ice shelf in the Weddell Sea in May 2021, but it has since fragmented into three pieces. 

‘Calving of icebergs from Antarctica’s ice shelves is part of the natural life cycle of glaciers,’ said Professor Geraint Tarling, Ecosystems Science Leader at BAS.

Leave a Comment