Greenland Ice Melt Could Raise Sea Higher Than Expected

Greenland has more ice vulnerable to climate change than scientists once realized. Researchers have determined that the "shallow" glaciers that edge Greenland's coast actually stretch approximately five dozen miles inland - potentially contributing more to rising sea levels than previously thought.

Past assessments of climate change have all shown the same thing: Melting glaciers around the world are raising the sea level, and the ice melt in Greenland contributes heavily to this rise.

To predict just how much the ocean will be raised annually by Greenland's ice melt, NASA's Operation IceBridge began measuring and mapping the icy region's topography in 2009. Since then, the project has tripled what we know of Greenland's surface. Back in 2012, disturbing new footage from NASA satellites showed that the massive island's ice sheet was undergoing an unprecedented melt, resulting in a 97 percent loss of the surface sheet by mid-July.

However, according to researchers from the University of California in Irvine (UCI), these assessments of Greenland's ice melt literally only skimmed the surface of the problem.

A new study published in Nature Geoscience details how analysts were able to estimate the extent of Greenland's sub-surface ice despite the fact that conventional radar pinging and satellite readings are incapable of measuring to great depths along the icy coast.

Using a novel "mass conversion algorithm," researchers found that the apparently shallow glaciers that make up Greenland's coast actually stretch an average of nearly 65 miles inland underneath the island's bedrock.

"The glaciers of Greenland are likely to retreat faster and farther inland than anticipated - and for much longer - according to this very different topography we've discovered beneath the ice," lead author Mathieu Morlighem said in a UCI news release. "This has major implications, because the glacier melt will contribute much more to rising seas around the globe."

The study was published in Nature Geoscience on May 18.