A massive 490 square mile iceberg over 20 times the size of Manhattan broke off from the Brunt Ice Shelf, probably the most closely monitored ice shelf on Earth, near a British research station in Antarctica this past week. So that’s not normal. Or is it?
According to the British Antarctic Survey (BAS), they first started noticing cracks in the nearly 500-foot thick iceberg almost a decade ago.
As a result, BAS glaciologists (yes, that’s what they are called) have been expecting this giant slab of ice ever since they first detected growth of vast cracks in the ice – a process called “calving.”
“Our teams at BAS have been prepared for the calving of an iceberg from Brunt Ice Shelf for years. We monitor the ice shelf daily using an automated network of high-precision GPS instruments that surround the station, these measure how the ice shelf is deforming and moving,” BAS director Jane Francis said in a statement. “We also use satellite images from ESA, NASA and the German satellite TerraSAR-X. All the data are sent back to Cambridge for analysis, so we know what’s happening even in the Antarctic winter, when there are no staff on the station, it’s pitch black, and the temperature falls below minus 50 degrees C (or -58F).
“Over coming weeks or months, the iceberg may move away; or it could run aground and remain close to Brunt Ice Shelf. Halley Station is located inland of all the active chasms, on the part of the ice shelf that remains connected to the continent. Our network of GPS instruments will give us early warning if the calving of this iceberg causes changes in the ice around our station.”
Scientists believe that this calving should not be a threat to Halley Research Station, but they are still keeping a sharp eye on it.
“This is a dynamic situation. Four years ago we moved Halley Research Station inland to ensure that it would not be carried away when an iceberg eventually formed. That was a wise decision,” stated Simon Garrod, BAS Director of Operations. “Our job now is to keep a close eye on the situation and assess any potential impact of the present calving on the remaining ice shelf. We continuously review our contingency plans to ensure the safety of our staff, protect our research station, and maintain the delivery of the science we undertake at Halley.”
While many would speculate that this calving was caused by climate change, the BAS researchers say not so fast.
“Change in the ice at Halley is a natural process,” reads the BAS press release. “and there is … no evidence that climate change has played a significant role.”