A new study shows a slowdown in deep ocean currents, caused by melting Antarctic ice, is coming sooner than expected. An earlier study suggested that water circulation in the deepest parts of the oceans would slow by 40% by 2050 if emissions remained high.
But the study published Thursday in Nature Climate Change shows that this process has in fact already slowed by 30% between the 1990s and 2010. The implications could be significant, with Antarctica's deep ocean acting as a key "pump" for the global network of ocean currents.