Warm Atlantic currents, the biggest woolly jumper in the world.

The Atlantic Conveyor Belt

This is the name for a global network of vast ocean currents that circles the world. If it wasn't for the Atlantic Conveyor, it would be very cold in the UK. And it maybe shutting down.
 

Keeping Britain warm

Britain is as far north as parts of Canada, where it is cold enough for polar bears to live. We have a temperate climate because currents circulating in the Atlantic Ocean bring warm water from the tropics to northern Europe. The currents are part of the overturning circulation, or Atlantic Conveyor Belt. As they flow they release heat into the atmosphere which in turn warms the land. They act like a gigantic central heating system. The rate at which the currents carry heat northwards is equivalent to the power of about one million power stations.

A predicted slowdown

In 2001 computer models of climate showed that, as carbon dioxide in the atmosphere increases, the Atlantic Conveyor could slow down or turn off altogether. Since then scientists have found evidence of a slowdown but they need more data to confirm the trend exists.

Hollywood took up the idea in the disaster movie ‘The Day after Tomorrow’. Here the Conveyor turns off and triggers the arrival of a New Ice Age overnight. This is science fiction.

Climate models show that if the Conveyor turned off completely temperatures in Europe would fall by from 4°C to 6°C.  This would occur ten or twenty years after a slowdown.

What drives the Atlantic Conveyor?