Climate change sceptics won over by the evidence

The Earth really is getting warmer, according to new research by a US scientific group created in the aftermath of the 'Climategate' affair - and backed by opponents of any scientific evidence of global warming, the Koch brothers.

The Berkeley Earth Project began after University of California physics professor Richard Muller became concerned that earlier climate researchers had not been entirely open with their data, when emails leaked in 2009 from the UK's University of East Anglia led to allegations that research had been manipulated.

But after further research using new data and techniques, the Berkeley group has confirmed the same trend towards global warming observed by earlier studies, including data from 40,000 weather stations around the world whose output has been digitally recorded.

Overall, the study - which is published on the group's website - found that the Earth's temperature over land has risen by 1 degree C since 1950. The group's findings mirror closely those of three earlier studies shown in the graph below, and widely decried in climate sceptic circles.

"Our biggest surprise was that the new results agreed so closely with the warming values published previously," Muller said of the group's results, which have been published on its website. "This confirms that these studies were done carefully and that potential biases identified by climate change sceptics did not seriously affect their conclusions."

The new study received a cautious reception by Professor Phil Jones, the University of East Anglia Climate Research Unit scientist heavily criticised during 'Climategate', because it had not been published in a peer-reviewed journal.

But from other quarters, the welcome was wholehearted.

"This study also proves once again how false it was for 'sceptics' to allege that the e-mails hacked from UEA proved that the CRU land temperature record had been doctored," said Bob Ward, policy and communications director for the Grantham Research Institute for Climate Change and the Environment in London.

"It is now time for an apology from all those, including US presidential hopeful Rick Perry, who have made false claims that the evidence for global warming has been faked by climate scientists."

The Berkeley team plans to follow-up its land-based research by looking at ocean temperatures to build up a more complete picture of climate change.