The Greenland ice sheet is melting quicker than what scientists had previously thought. The largest ice sheet on the northern hemisphere that stretches nearly 656,000 square miles – and averages a thickness of more than a mile is dissipating at a faster pace than what scientists thought before. Just a few weeks ago scientists were talking about the extreme ice melt that was taking place in Western Antarctica. However, scientists believe that the ice melt in the Greenland ice sheet is likely as bad, or worse than the ice melt that is taking place on the southern hemisphere.

The issue at hand is that between the two ice sheets melting at the rate that they are, as the new estimates are significantly higher than what previous models suggested – and even up the ante from what the United Nations’ Intergovernmental Panel on Climate Change suggested.

Overall, the new estimates are born from two separate studies – both of which paint a grim picture of what the future will look like when it comes to the Earth’s coastlines.

For the first study, scientists from the University of Buffalo used laser altimetry to measure a series of elevation points atop Greenland’s ice sheet. Altogether 100,000 points were measured, and then compared to results from 1993 and 2012. The findings suggested that .68 millimeters of annual sea level rise would be expected moving forward. That’s alarming to scientists because that’s a greater annual sea rise than is forecasted in Western Antarctica. That would be equal to roughly 3 ½ inches of water rise in the world’s oceans at the hands of that kind of ice melt.

The second study evaluates the progress of what are known as “supraglacial lakes.” These are lakes that form and sit on top of the glacial ice, and then sometimes disappear into “mounlins,” or the crevices that exists between the patches of ice. These crevices are incredibly deep and give the water that exists – which is warmer due to its depth in the lakes – to spread more heat throughout the ice sheet and promote more melting. Something that would increase the production of melting ice throughout the Greenland ice sheet.

These two studies both paint an incredibly grim picture about what the future will look like for the Earth’s coast line, and major coastal cities all over the globe.

NASA/UB