Further evidence that global warming is due to human activity was published today.
British and Swiss researchers have reported that the rise in global temperatures that has been detected over the past two decades cannot be blamed on the Sun.
They had examined data for radiation from the Sun, levels of which can cool or warm the planet's atmosphere.
In a paper published in the Proceedings of the Royal Society, in London, the team said that the Sun had been less active since 1985, even though global temperatures have continued to rise.
The study is co-authored by Mike Lockwood of Britain's Rutherford Appleton Laboratory and Claus Froehlich of the World Radiation Centre in Switzerland.
Most scientists say emissions of greenhouse gases, mainly from burning fossil fuels in power plants, factories and cars, are the prime cause of the current warming trend.
A dwindling group pins the blame on natural variations in the climate system, or a gradual rise in the sun's energy output.
The Royal Society, one of the world's oldest scientific academies, founded in 1660, said the new research was an important rebuff to climate change sceptics.
'At present there is a small minority which is seeking to deliberately confuse the public on the causes of climate change,' it said in a statement.
The Society added 'They are often misrepresenting the science, when the reality is that the evidence is getting stronger every day.'
