Study: Sun not linked to climate change

LONDON, April 3 (UPI) -- A British study casts doubt on the theory that global warming is caused by cosmic rays rather than human activity.

Climate change skeptics argue that cutting carbon emissions is futile because they believe climate change is caused not by burning fossil fuels but by changes in cosmic rays that determine cloudiness and temperature.

Physicist Terry Sloan of Lancaster University and Arnold Wolfendale of Durham University said their research finds no evidence of a link between the ionizing cosmic rays and the production of low cloud cover.

"This is of vast significance because if the skeptics are right, it would mean we're wasting our time trying to cut greenhouse gases," the researchers said in a statement. "But we couldn't find the link they were proposing which means we are right to be cutting carbon emissions."

The cosmic ray theory was developed by Danish scientist Henrik Svensmark at the Danish National Space Centre and featured in a controversial British documentary, "The Great Global Warming Swindle." Svensmark suggested that when the solar wind is strong, the planet warms up because fewer clouds are produced and more of the sun's heat reaches the surface.