Largest iceberg in 50 years breaks off Antarctic ice shelf

The biggest iceberg in more than 50 years has broken off the Amery Ice Shelf in Antarctica.

The iceberg, named D28, covers around 1600 square kilometres and is estimated to weigh 315 billion tonnes.

It's so large that it's likely to take several years to disintegrate and melt. In the meantime, it will need to be monitored and tracked in case it becomes a hazard to shipping.

Australian Antarctic Division (AAD) glaciologist Ben Galton-Fenzi says the iceberg separated from the shelf last Thursday.

"The calving will not directly affect sea level, because the ice shelf was already floating, much like an ice cube in a glass of water," Dr Galton-Fenzi told ABC.

"But what will be interesting to see is how the loss of this ice will influence the ocean melting under the remaining ice shelf and the speed at which the ice flows off the continent."

Helen Amanda Fricker, a professor and glaciologist at the Scripps Institution of Oceanography, says scientists have been expecting an iceberg to calve from the area for the past decade.

"I am excited to see this calving event after all these years. We knew it would happen eventually, but just to keep us all on our toes, it is not exactly where we expected it to be," she told the BBC.

But scientists say that climate change was not a factor in the iceberg leaving Antarctica. Prof Fricker said that the "calving event is part of a healthy ice shelf cycle".

"While there is much to be concerned about in Antarctica, there is no cause for alarm yet for this particular ice shelf," she added.

However even this Amery Ice Shelf iceberg is dwarfed by a one trillion tonne iceberg, which broke off from Antarctica's Larsen C Ice Shelf in 2017.

Newshub.