Gulf Stream is not slowing down, scientists claim
Published 30/03/2010 | 15:52
The Gulf Stream is not being slowed down by climate change, a study indicates.
Research suggests that fears that Ireland could be plunged into an ice age by a waning Gulf Stream are unfounded.
The current, responsible for Ireland ’s mild climate by bringing a constant flow of warm water and weather from the tropics, has not significantly changed in nearly 20 years, scientists said.
They believe that small differences observed in its pace since research began in 1993 are part of a natural cycle.
The findings call into question theories proposed by some environmentalists that global warming could shut down the stream, causing temperatures to fall dramatically in Europe.
Such a catastrophe was dramatised in the apocalyptic Hollywood film The Day After Tomorrow, and is predicted in some computer models of climate change.
A team of NASA scientists used satellites to monitor changes in the height of the sea to follow changes in the flow of the Gulf Stream.
They found that between 2002 and 2009, there was no discernible trend and that its flow changed vastly over the seasons.
Satellite records dating back to 1993 did suggest a minor increase in flow overall, although the researchers believe it is too small to be significant.
Dr Josh Willis, from Nasa's Jet Propulsion Laboratory (JPL) in California, said: “The changes we’re seeing in overturning strength are probably part of a natural cycle.
"The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling."
The Gulf Stream is crucial in maintaining the mild climate in Britain and Europe. Without the flow of warm water from the Mid Atlantic, the British Isles would be 4-6c colder than they are.
It forms part of a larger movement of water, known as the Atlantic Meridional Overturning Circulation, and is driven by surface winds and differences in the density of water.
The new research is published in the journal Geophysical Research Letters.