The "Atlantification" of the Arctic Ocean is underway. And no, that doesn't mean we're about to get the polar bear version of Outkast, but rather that the Arctic Ocean is rapidly becoming more like the Atlantic Ocean, according to new research published Thursday. The Arctic Ocean has historically been separated into two layers: a cold, less salty layer on top with a salty, warmer layer of Atlantic water underneath, Scientific American reports. The barrier between the two is called the cold halocline layer, and it's been responsible for preserving Arctic sea ice, according to Science. But the separation between the layers has been quickly breaking down over the past decade or so.
The temperature difference between the two layers has lessened by 2 degrees since 2002, and the top layer of cold water has gotten thinner in the past decade—possibly by as much as 180 feet. From 2013 to 2015, the layers merged completely in some areas. The loss of the cold halocline layer means sea ice in the Arctic is getting attacked from both sides. Warming air and warming surface ocean temperatures are creating a "positive feedback loop" that is decimating the ice. Sea ice in the Arctic is decreasing by 13% every decade, and soon the Arctic Ocean could be entirely ice-free during the summer. Between warmer water with more nutrients and no more ice to block the sun, it's unclear what will happen to the Arctic's ecosystem, Inverse reports. (One woman's desperation advanced Arctic exploration.)