As Antarctic ice melts, all of that fresh water pours into the ocean, essentially diluting it by reducing its salinity. That, in turn, is dramatically slowing the currents that, like a conveyor belt, carry oxygen, carbon dioxide, and nutrients through the sea and around the world.
A study published last week in the journal Nature modeled the impacts of this phenomenon, called overturning circulation, on the deepest ocean currents, particularly in the southern hemisphere. It found that the world is on the verge of a potentially catastrophic slowdown, which could have a devastating effect on climate change, marine ecosystems, and the stability of Antarctic ice.
