Fears that global warming will shut down the Gulf Stream and plunge Britain into a mini-ice age are unfounded, a study shows.

There is no evidence the phenomenon - which brings a constant flow of warm water and mild weather to northern Europe - has slowed down over the past 20 years, climate scientists say.

'The changes we're seeing in overturning strength are probably part of a natural cycle,' said researcher Josh Willis, from Nasa.

Image
Cold reality: Some scientists had predicted that global warming would cause the Gulf Stream to slow triggering an ice age in Britain
The Gulf Stream is vital to Britain's mild climate. Without the flow of warm water from the Mid Atlantic, the British Isles would be 4-6c colder than they are.

Some environmentalists have argued that global warming could shut off the stream - sending temperatures spiralling down across Europe as they rise elsewhere.

The controversial scenario was dramatised in apocalyptic Hollywood blockbuster The Day After Tomorrow and is predicted in some computer models of climate change.

The idea that a slowdown of the ocean currents would trigger such a rapid change in climate is pure fantasy, explained Dr Willis.

Comment: Well, given the kind of fantasy NASA, NOAA and the IPCC have engaged in for the past decade and more, forgive us for taking anything uttered by the "experts on climate change" with large quantities of sea salt. The sudden shutdown of the North Atlantic Drift bringing a dramatic chill to Europe is a concept that is taken seriously in many quarters, including some in NASA.

'But the Atlantic overturning circulation is still an important player in today's climate,' he added.

'Some have suggested cyclic changes in the overturning may be warming and cooling the whole North Atlantic over the course of several decades and affecting rainfall patterns across the U.S. and Africa, and even the number of hurricanes in the Atlantic.'

Image
Hollywood dramatisation: The Day After Tomorrow depicts the catastrophic effects of climate change
The study used satellite data to study the pattern of Atlantic currents between 2002 and 2009. Researchers from Nasa's Jet Propulsion Laboratory found no long-term trend, just short-term variability, according to the study published in Geophysical Research Letters journal.

The Gulf Stream is one of the strongest currents in the world. It is driven by surface winds and differences in the density of water.

Fears that the circulation was slowing emerged in a study by the UK National Oceanography Centre in 2005.

The United Nation's Intergovernmental Panel on Climate Change's last report in 2007 said it was 'very likely' that the Gulf Stream will slow down during the next 100 years.

Most climate models suggest it will slow down by one quarter over the 21st century.

Although the slowing of the Gulf Stream would have a cooling effect on Europe, the IPCC claims temperatures will still rise overall.