Scientists have reported that an iceberg nearly the size of Delaware could break away from one of Antarctica's largest ice shelves within months.
Growing Crack In Antarctica's Larsen C Shelf
The looming break-off is blamed on the crack in the ice shelf called Larsen C that has been growing at an accelerating rate. The rift, which has grown to about 60 miles long and about 300 feet wide, has left only 12 miles of ice connecting the chunk to the rest of the floating ice shelf.
Scientists Not Alarmed
If the crack grows by another dozen miles, the iceberg may break off and float away but some scientists watching the growing crack are not alarmed.
University of Colorado scientist Ted Scambos said that the chunk of ice may break off soon possibly in March this year and this would eventually change the shape of the ice shelf.
Scambos and other scientists, however, said that they do not see other key signs that the crack would cause a catastrophic collapse of the entire shelf. Scambos said on Friday that although a chunk of the ice will break off, it will not lead to runaway disintegration of the shelf.
A Natural Phenomenon
Jay Zwally, a NASA glaciologist, said that large icebergs periodically break off from Antarctica naturally.
"By itself this calving is not a cause for alarm," Zwally said. "The ice shelf has been thinning as other ice shelves have been thinning in the Antarctic peninsula."
Although climate change would come up as a likely culprit for the event, scientists said that they have no direct evidence that support a causal link. They said that the break-off is not a climate event but a geographical one.
In a tweet, Project Midas, a UK-based Antarctic research project that investigate the effects of the warming climate on the Larsen C ice shelf, said that the break-off is a normal phenomenon.
There’s no need for alarm! This is a fairly normal event, although it is spectacular and quite rare https://t.co/xwKOOKLicD
— Project MIDAS (@MIDASOnIce) January 6, 2017
Concerns For Eventual Consequences Of The Break-Off
Concerns, however, remain on the eventual impact of the break-off. The consequences of this break-off could be on the ice shelf and these could gradually happen in years or decades.
Ice shelves are sheets of floating ice that protect and support inland glaciers. Although the separated iceberg would not raise sea levels when it flows aways from the shelf, it could accelerate further breakup of the ice shelf. A possibility looms that if the shelf breaks up even more, it would eventually cause a rise in the world's sea level.
It is estimated that global waters would rise by 3.9 inches if all of the ice that the Larsen C shelf now holds back enter the sea.
"Ice shelves serve a critical role in buttressing ice that's on land," said NASA scientist Thomas Wagner said.