Iceberg Nearly as Large as Amsterdam Detaches from Antarctic Ice Shelf

According to a BBC report, a sizable iceberg has broken away from the region of Antarctica that is home to the UK’s Halley research facility. The 380 square kilometer iceberg is almost as large as Amsterdam and about the size of the Isle of Wight in the United Kingdom. It is the third iceberg to break off close to the surface in the previous three years. A few weeks ago, a crack on the ice shelf suddenly appeared, causing the iceberg to break off. The last pause occurred in the wee hours of May 20.

The iceberg calved after a 14-kilometre-long split emerged at 90 degrees from the existing Halloween Crack. This comes after a long period of ice weakening at McDonald’s Ice Rumples, according to the British Antarctic Survey. Notably, there is no evidence that the calvings are related to climate change.

The British Antarctic Survey relocated the research facility in 2017 because of worries about how the ice was acting, according to the BBC. Skis were used to move its buildings to a safe distance from any potential threats. Halley is perched atop the Brunt Ice Shelf, a glacier outcrop that the continent has slid into the Weddell Sea. Currently undergoing a highly dynamic phase, this shelf will occasionally drop icebergs at its forward edge.

Moreover, the staff members have been deployed to the research centre only during the Antarctic summer, which begins in November and lasts till March. A new team will return to Halley in November.

Dr Oliver Marsh, a glaciologist with four seasons of experience on the Brunt Ice Shelf, initially discovered the calving using GPS technology. “This calving was expected since the appearance of Halloween Crack eight years ago and reduces the total area of the ice shelf to its smallest extent since monitoring began,” he said.

“Tabular iceberg calving is part of the natural behaviour of ice shelves but often causes large changes in ice shelf geometry and can impact local ocean circulation. Our science and operational teams continue to monitor the ice shelf in real-time to ensure it is safe, and to maintain the delivery of the science we undertake at Halley,” he continued.

Professor Adrian Luckman, a professor at Swansea University, who studies Antarctic ice shelves, added, “Antarctica’s floating ice shelves grow gradually by ice flow and shrink episodically by iceberg calving. The balance between these two processes impacts their ability to hold back ice on land. It is concerning, therefore, that even in this relatively cold sector of Antarctica there have now been three large iceberg calvings in the last 3-4 years. The Brunt Ice Shelf is providing plenty of data to help us understand the calving process and predict the future evolution of these important ice bodies.”