Around 61% of the world's freshwater is locked up in Antarctic ice—but a new study warns that accelerating melting on the continent is helping push up the sea levels around it. Researchers found that between 1992 and 2011, sea levels rose more around Antarctica than in the Southern Ocean as a whole. "Freshwater is less dense than salt water, and so in regions where an excess of freshwater has accumulated we expect a localized rise in sea level," the author of a study published in Nature explains to the BBC.
The researchers say their models suggest freshwater runoff, not natural fluctuations, is the only explanation for the 2mm-per-year rise. "We can estimate the amount of water that wind is pushing onto the continental shelf, and show with some certainty that it is very unlikely that this wind forcing is causing the sea level rise," the lead researcher says. The researchers say the freshening of the water may explain growth in sea ice in the area, though that growth comes as new satellite-produced maps show that ice sheets on land are melting at an unprecedented rate, the Guardian notes. (Last month, researchers revealed that they had found life half a mile below the West Antarctic Ice Sheet.)