Ocean floor sensors will warn of failing Gulf Stream | Environment | The Observer

A new sensor network to monitor the Gulf Stream:

An armada of robot submarines and marine sensors are to be deployed across the Atlantic, from Florida to the Canary Islands, to provide early warning that the Gulf Stream might be failing, an event that would trigger cataclysmic freezing in Britain for decades.

The £16m system, called Rapid Watch, will use the latest underwater monitoring techniques to check whether cold water pouring south from melting Arctic ice sheets is diverting the current's warm waters away from Britain....

in 2004, Dr [Meric] Srokosz - with his Southampton colleagues Professor Harry Bryden and Dr Stuart Cunningham - set up Rapid, a temporary array of sensors fixed to the seabed that provided daily measurements of the Gulf Stream for the first time. The first results, which were published last year, revealed that the Gulf Stream fluctuates in a highly unpredictable fashion.

'The Gulf flows at an average rate of 20 million cubic metres per second,' added Srokosz. 'But this flow varies from as little as four million cubic metres to about 35 million. This means past isolated measurements could be highly misleading.'

As a result, Srokosz has designed Rapid Watch, which has just received £16m from the Natural Environment Research Council. 'Rapid was a proof of concept study,' he said. 'Rapid Watch is a full-scale detection system.' Rapid Watch, which will begin operations later this year, will monitor the Gulf Stream until 2014. Cables will moor monitoring devices to the seabed and measure current flow, temperature and other variables at depths down to 5,000 metres.

In addition, robot probes - called gliders - will study the current as they descend and ascend. 'Robot gliders can currently operate to depths of about 1,000 metres, but soon versions that can dive to 5,000 metres should be ready.

'Certainly, it is critical we now find out how the Gulf Stream is behaving,' added Srokosz. 'It has an immense influence on our climate - and our lives.'