The Arctic and Antarctic spheres, each have their own reasons to fear, now. The glacier meltdown at Canada’s Arctic circle is increasing the sea-level on one side, in the North. On the other side, deep down in the South, Antarctic waters are now witnessing blocks of ice floating on them.
The Pine Island Glacier has shed another block of ice. This one seems to be tinnier compared to the icebergs that broke off in 2014 and 2015. The event proves the ice shelf’s fragility, adding to several other evidences.
Pine Island is one of the main glaciers responsible for moving ice from the interior of the West Antarctic Ice Sheet to the ocean. It delivers about 79 cubic kilometers of ice per year into the Pine Island Bay.
The scientists are studying this glacier closely, as this points out to a faster loss of ice in the near future. They also fear that such a retreat would lessen the shelf’s buttressing effect. This would allow more inland ice to flow out to the ocean, ultimately melting and contributing to sea level rise.
Landsat 8, American Earth Observation satellite by NASA, captures an image of Pine Island Glacier’s floating edge on 26 Jan. 2017, after the recent break.
Ian Howat, a glaciologist at Ohio State University, says that the event was about 10 times smaller than in July 2015. Also, she said that in 2015, a 30-kilometer-long rift developed below the ice surface. This then broke through and calved an iceberg spanning 583 square kilometers. She said, “I think this event is the calving equivalent of an ‘aftershock’ following the much bigger event”.
“Such a ‘rapid fire’ calving does appear to be unusual for this glacier”, Howat adds. The phenomenon fits into larger picture of basal crevasses in the center of the ice shelf being eroded by warm water. This, thereby causing the ice shelf to break from the inside out. Scientists expect that these rifts will result in more calving in the near future.