An ice sheet in Antarctica is melting not because of warm air, but due to warm water flowing beneath it and a team of international researchers believe this could be going on in multiple ice shelves.

According to a press release, researchers at Penn State University (PSU) aided in studying the melting of the Pine Island Glacier's floating ice shelf in Antarctica. The Pine Island Glacier (PIG) has been rapidly melting recently.

"We've been dumping heat into the atmosphere for years and the oceans have been doing their job, taking it out of the air and into the ocean," said Sridhar Anandakrishnan, professor of geosciences, PSU. "Eventually, with all that atmospheric heat, the oceans will heat up."

The researchers at Penn State performed the geophysics for the project, whose results were published Friday in the journal Science.

The team gathered data on PIG by drilling holes in the surface of the ice and used instruments with radar capabilities to map the underside of the ice shelf and the bottom of the ocean.

Water can transfer more heat than air and the flow of water underneath the shelf is causing the rapid melting. Channels through which water flows beneath the ice have become large enough to now allow it to flow out to the ocean and for warmer water to flow in.

"The way the ocean water is melting the ice shelf is a deeply non-uniform way," said Anandakrishnan. "That's going to be more effective in breaking these ice shelves apart."

As the PIG, which is located on land, continues to melt, it will add more ice shelf mass to the water, which will contribute to already rising sea level. Anandakrishnan said the study is a forewarning of what will happen further down the line.

"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."