Scientists have long thought that the the world’s oceans play a key part in reducing the amount of carbon in the atmosphere, but a team of British and Australian scientists recently discovered precisely how this process works. The team found that naturally occurring funnels suck carbon dioxide deep into the Southern Ocean, where it is safely stowed away – however the team believe that this process may be threatened by the onset of climate change.
The carbon-sucking funnels in the Southern Ocean are created by the confluence of wind, ocean eddies and currents. The research team estimated that about a quarter of the carbon dioxide on Earth is located under the world’s oceans, but of that 40% is in the Southern Ocean.
The team, led by Jean-Baptiste Sallee, found that the carbon is sucked down to a depth of about 1,000 meters where it is locked away for hundreds to thousands of years. The scientists are not exactly sure how it gets there once it dissolves into the ocean waters, although they believe that the wind plays a key role in forcing it down. The sheer size of these funnels is amazing – after looking at 10 years of data, the research team realized that this ‘carbon sucking phenomena’ were, on average, 100 kilometers in diameter!
“You add the effect of these eddies and the effect of the wind and the effect of prominent currents in the Southern Ocean, you add these three effects, it makes … 1,000 km-wide funnels that bring the carbon from the sea surface to the interior,” study author Jean-Baptiste Sallee said to reporters. “This is a very efficient process to bring carbon from the surface to the interior. We found in the Southern Ocean there are five such funnels.” said Sallee.
The team also found that the eddies counterbalanced the release of stored carbon due to the violent mixing of the sea. “This does seem to be good news, but the thing is what will be the impact of climate change on the eddies? Will they stop, will they intensify? We have no idea,” said Sallee.
The team also don’t know whether the same funneling process occurs in the same way in the world’s other oceans, but Sallee noted that Southern Ocean was “one of the most energetic places on Earth”, and any such funnels would be bigger there than anywhere else.