Ocean study ripples current thinking

28 November 2008

New research on the major ocean current off southern Africa reveals an important effect far away in the north Atlantic - with potential consequences for our climate. Antenna catches the drift...

This research was published in the journal Nature on 27 November 2008.

Broadband Version

Modelling of the ocean currents around southern Africa from 2000 to 2004.

Video: Arne Biastoch

The researchers gathered existing data, such as temperature and salt content, for the Agulhas current off southern Africa. This information was fed into powerful computer simulations, which gave the researchers a valuable insight into how the current moves.
So what do the simulations show?

'Our model shows that water from the Agulhas current affects currents in the north Atlantic much faster than previously thought. Changes in the Agulhas current should be noticeable in currents thousands of miles north of it,' explains team leader Arne Biastoch.

Arne Biastoch, ocean scientist, Leibniz Institute of Marine Sciences, Germany.

Image: Arne Biastoch

It could have important consequences for our climate. The Gulf Stream, a key north Atlantic current, warms the UK, keeping us relatively toasty for where we are on the planet. If the Gulf Stream turned off because of changes in other ocean currents we'd be in for a big chill.

The Gulf Stream carries warm water from the tropics to Europe, releasing its heat into the air. The cool water then flows back south, where it warms up and starts the cycle again.

Image: Wikipedia Commons

So what's the next step?
'The currents around southern Africa need to be included in future modelling of the north Atlantic currents so that we have a better understanding of how they work.' Arne Biastoch
What do other experts think?

'This research shows that we need more understanding of how ocean currents affect each other to predict the future climate, and more importantly monitor the effect of global warming,' explains Gulf Stream expert Torsten Kanzow.

Torsten Kanzow, Gulf Stream expert, Southampton University.

Image: National Oceanography Centre