One of the largest glaciers on Earth is quickly melting, according to measurements taken by scientists. The Totten Glacier in East Antarctica is losing about 32 feet of its thickness annually, and warm ocean water is to blame.
Scientists from both the United States and Australia took ocean temperature samples from far below Totten glacier’s floating ice shelf. Analysis of the numbers determined warm ocean water is flowing underneath the glacier at 220,000 cubic meters per second.
This movement of warm water is reducing the mass of the glacier anywhere between 63 and 80 billion tons every year. The moving water is melting the ice sheet at the point it hits the ground. According to the survey, Totten glacier is melting faster than any other glacier in East Antarctica.
“This ice shelf is thinning, and its thinning because the ocean is delivering warm water to the ice shelf, just like in West Antarctica,” said Don Blankenship, a glaciologist at the University of Texas at Austin and one of the study’s co-authors, as cited by the Independent.
Scientists are particularly worried about the Totten Glacier melting as more ice drifts toward the ocean through this region than anywhere else in East Antarctica. The amount of ice that slowly moves through the area is larger than the state of California. Should this amount of ice melt and flow into the ocean, sea levels worldwide could rise nearly 12 feet.
The research team, led by Stephen Rintoul with the University of Tasmania in Hobart, sailed aboard the Aurora Australis to reach the Totten ice shelf in January 2015. The team was able to take ocean measurements at 10 different points along the ice shelf when an unexpected hole in the sea ice allowed the vessel to get closer than ever before.
“We knew the Totten has been thinning faster than other glaciers in East Antarctica, but nobody has known exactly why until we took these measurements,” said Rintoul, per a report from ABC News. “We found that warmer ocean water is reaching the cavity through this channel at temperatures capable of melting the ice shelf at the point where it meets ground.”
The ocean temperature measurements were taken at different depths ranging from 200 and 3,600 feet. The samples revealed warm water, named “modified circumpolar deep water,” was flowing toward the glacier. The underwater river is approximately six miles wide, half a mile deep, and runs near the western side of the glacier.
However, labeling the water “warm” is misleading. The actual temperature of the water is slightly below the freezing point, but due to pressures from extreme depths, the freezing point of ice is slightly lower. This lower freezing point makes the water beneath warm enough to thaw the glacier.
Until the research team discovered the warm water underneath the Totten Glacier, scientists could only speculate what was going on. Previous research suggested there were pockets inside where warm water would enter, causing the glacier to shrink and sink into the water.
Scientists fear the global consequences should Totten melt and fall into the ocean. During a prior period of warm climate experienced in the Pliocene Era, approximately 3 million years ago, worldwide temperatures and glacial melting caused a significant rise in sea levels. While not certain, scientists do not believe the melting of only the Totten Glacier would be enough to cause the same surge in ocean levels.
In Antarctica, the ice sheets covering the land are so massive, they actually extend out into the ocean. East Antarctica holds about 66 percent of all the ice on the continent, so a massive meltdown would have dire significance to worldwide coastal areas.
The research team’s report on the melting of Totten Glacier in East Antarctica was published Friday in the journal Science Advances.
[Featured Image by Torsten Blackwood – Pool/Getty Images]