NASA’s scientists have expressed concern about a potential problem if an iceberg twice the size of New York City broke off from Antarctica’s Blunt Ice Shelf. Moreover, they are also concerned about what would happen to the remaining shelf, as a science research station could be sitting on a part of the ice shelf that could become unstable.
It’s no secret that the warmer global ocean temperatures and climate change work together in melting the ice-shelves on the southern continent. However, the pieces of ice that break off are no longer so small. There are more icebergs than usual that have already broken off and floated into the ocean, but scientists are particularly concerned about this shelf, as the British Antarctic Survey’s Halley Station is located on it, and possibly in danger’s way.
Cracking across Antarctica’s Brunt Ice Shelf is set to release an iceberg w/ an area about 2x the size of NYC. The splitting could result in an uncertain future for the shelf’s scientific research & human presence. See what @NASAEarth satellites captured: https://t.co/Atppp05I5j pic.twitter.com/WrI1p3bqVC
— NASA (@NASA) February 24, 2019
Scientists fear that the iceberg twice the size of New York City could emerge off the Blunt Ice Shelf, after observing the newly-grown cracks across the ice shelf in the last few years.
“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,” the scientists wrote on the website.
“The near-term future of Brunt Ice Shelf likely depends on where the existing rifts merge relative to the McDonald Ice Rumples,” Joe MacGregor, a glaciologist at NASA’s Goddard Space Flight Center said in the statement. “If they merge upstream (south) of the McDonald Ice Rumples, then it’s possible that the ice shelf will be destabilized.”
The latest observations and photos were made on Jan. 23, showing an ice crack called the Halloween crack, mainly because it appeared in October 2016. However, the crack has progressed and continued to grow eastward. Another crack, called Chasm 1, has caused scientists to be even more concerned, because even though the crack was stable for 35 years, it has been progressing faster and recently began accelerating toward the north at about 2.5 miles per year, heading toward the Halloween crack.
When the crack cuts all the way across, it could result in 660 square miles of ice breaking off the shelf. Scientists noted that even though that break wouldn’t make it to the top 20 list of icebergs that have broken off of ice shelves, it would be the largest one that will have broken off the Brunt Ice Shelf since 1915, when measurements began.
NASA said that the calving process is normal in the ice shelves life cycle. However, these accelerated changes are worrisome and unfamiliar for that area. The ice shelf was surveyed by Ernest Shackleton in 1915, and since then its edge hasn’t been evolving as fast as in the last few years.
“We don’t have a clear picture of what drives the shelf’s periods of advance and retreat through calving,” NASA/UMBC glaciologist Chris Shuman said. “The likely future loss of the ice on the other side of the Halloween Crack suggests that more instability is possible, with associated risk to Halley VIa.”