Antarctic Ocean Currents Slowing

Australian scientists who are studying the phenomenon say that the deep ocean currents around Antarctica are slowing down and will eventually collapse. If that happens, it could have disasterous climate effects and reduce the oceans' capability to absorb carbon dioxide. Their study was published in the leading scientific journal, Nature The Earth's ocean currents and weather are driven by currents of heavy salt water descending to the seabottom around Antarctica. As the continent's ice cap melts producing lighter fresh water which slows the downward movement. Computer modeling shows that this overturning of ocean water will decrease by 40% in the next 30 years on a trajectory to collapse. Changes in the Atlantic Meridonal Overturning Circulation (AMOC)could cool northwester Europe significantly. This system is now weaker than it has been in the last 150 years.

The Antarctic current slowdown will also affect ocean ecosystems since the upwelling current brings nutrients from the seabed closer to the surface. One of the current features of the southern sea is the abundance of nutrients that feed plankton and fish that in turn are consumed by larger animals such as whales, seals, penguins and dolphins. The effect of Antarctic meltwater on ocean currents has not yet been factored into IPCC climate change models, but the effect will be significant.