The Antarctic Ocean Current threatens to slow dramatically: a drama for our climate | Science and the planet

These currents transport important elements—such as heat, oxygen, carbon, and nutrients—around the globe. Previous research has already shown that a slowdown in the North Atlantic Current could make Europe colder. In addition, the Australian study also shows that slowing currents may make it more difficult for the ocean to absorb carbon dioxide from the atmosphere.

The report explains how Earth’s network of ocean currents is driven in part by the downward movement of cold, dense, salty water to the seafloor near Antarctica. If fresh water melted from the southernmost ice sheet of our planet, then sea water would become less salty and denser. As a result, the downward movement of currents will slow down.

Scientists said that the deep currents in the oceans of the northern and southern hemispheres have been stable for thousands of years, but are now being hindered by a warming climate. “Our calculations show that if global carbon emissions continue at current rates, the Antarctic vortex will slow by more than 40 percent over the next 30 years,” said oceanographer Matthew England, the scientist who led the study. Eventually it can reach a complete dead end. “If the oceans had two lungs, this current would have one.”

Another scientist involved in the study, Adele Morrison, explained in a press conference that as ocean circulation slowed, surface waters quickly reached their maximum capacity of how much carbon they could absorb. According to Morrison, this will have more consequences for marine ecosystems than for Antarctica itself. “Deep ocean currents bring nutrients – which sink to the bottom when organisms die – to replenish nutrients for the global ecosystem and fisheries.”

According to scientists, deep water currents in Antarctica can slow down twice as fast as the North Atlantic current. “It’s amazing to see this happen so quickly,” climate scientist Alan Meeks told Reuters. “It now appears to be gaining momentum. This is important news.”