Underlying Ocean Melts Ice Shelf, Speeds Up Glacier Movement

"Warm ocean water, not warm air, is melting the Pine Island Glacier's floating ice shelf in Antarctica and may be the culprit for increased melting of other ice shelves, according to an international team of researchers.”

Penn state researchers have been studying atmospheric heat effects by looking at the remote Pine Island Glacier, or PIG, which has been rapidly thinning recently. Since PIG is in such a remote part of Antarctica it has taken years to collect proper data by drilling holes in the ice to place a variety of instruments and using radar to map the underside of the ice shelf and the bottom of the ocean. The study was done December through January 12-13, and Penn State’s research teams results were just reported Sept. 13, 2013.

The researchers have noted that the oceans are warmer than they have been in the past and this is causing the bottom of the ice shelf to melt more quickly. Also the terrain beneath the ice shelf is a series of channels, and the channels allow the water to flow out to the open ocean and warmer water to flow in, again melting the ice shelf from beneath. Although these ice shelves are melting this extra water doesn’t contribute to the rising sea level because its already in the water, but since most of the Antarctic glaciers are 

on land, that will increase the sea level.

Researchers all have different opinions on the ice shelf and it’s effects, some say that it should be incorporated into the sea level rise models of global warming while other research shows that without the ice shelf and glacier, melting would occur at an even faster rate.”The Antarctic has been relatively quiet as a contributor to sea rise," said Anandakrishnan. "What this work shows is that we have been blind to a huge phenomenon, something that will be as big a player in sea level rise in the next century as any other contributor."