Southern Ocean Remains Major Carbon Dioxide Sink, Study Shows

Despite becoming warmer and fresher, the Southern Ocean — the massive body of water encircling Antarctica — still retains a huge capacity to absorb carbon dioxide from the atmosphere and transport it deep under the sea, a new study shows. Relying on a network of 3,000 robotic devices distributed from the surface of the Southern Ocean to a depth of 2,000 meters (6,562 feet), German researchers determined that the powerful Antarctic Circumpolar Current — which transports five times as much water as the Gulf Stream — has not yet lost any of its ability to absorb CO2 and drive it down to great depths, where it is stored. Scientists are concerned that a warming Southern Ocean could one day alter the flow of the the Antarctic Circumpolar Current and reduce its ability to absorb CO2 from the atmosphere; at present, the Southern Ocean pulls more CO2 out of the air than any of the world’s oceans. By comparing data from the 3,000 devices with data gathered by ships since the 1960s, researchers at the Leibniz Institute of Marine Sciences in Kiehl, writing in the journal Nature Geoscience, concluded that the Southern Ocean still remained a massive carbon sink.