1214 GMT September 23, 2019
They said this causes concerns about the ‘uncertain future’ the breakage would create for research opportunities there, express.co.uk reported.
Scientists have been observing the brunt ice shelf since 1915 but say this crack would be the biggest since observations began decades ago.
The scientists said, “It is not yet clear how the remaining ice shelf will respond following the break, posing an uncertain future for scientific infrastructure and a human presence on the shelf that was first established in 1955.”
A notable crack occurred in October 2016 which continues to progress east, but scientists said their more ‘immediate concern’ is the rift running through the brunt ice shelf.
NASA said the rift was “previously stable for about 35 years, this crack recently started accelerating northward as fast as 4km per year.”
Satellite images captured by NASA in January showed the rift, also known at the 'Halloween crack' which first appeared in October 2016.
This crack was extending east from the area known as the McDonald ice rumples.
Glaciologist at NASA’s Goddard Space Flight Centre Joe MacGregor said, “The near-term future of the brunt ice shelf likely depends on where the existing rifts merge relative to the McDonald ice rumples.
“If they merge upstream of the McDonald ice rumples, then it is possible that the ice shelf will be destabilized.”
NASA said the calving effect of the iceberg was part of the “life cycle of ice shelves, but the recent changes are unfamiliar in this area”.
Through satellite imagery and NASA research planes, they are able to discover and study icebergs.
In October a NASA research plane discovered a mile-wide rectangular iceberg with perfect right angles corners in Antarctica.
The iceberg was known as a ‘tabular iceberg’, recognizable by its cleancut edges.
This kind of iceberg forms when it breaks off ice shelfs with precision, but is rarely kept in its perfect state for long.
Glaciologist at the University of Maryland Kelly Brunt said in an interview to Live Science, “We get two types of icebergs.
"We get the type that everyone can envision in their head that sank the Titanic, and they look like prisms or triangles at the surface and you know they have a crazy subsurface.
“And then you have what are called ‘tabular icebergs’
“What makes this one a bit unusual is that it looks almost like a square.”