Global warming is looking an ever more certain phenomenon, according to research partly funded by climate change sceptics.
The study by the Berkeley Earth project, the most comprehensive independent review of weather records to date, concluded that the Earth really is getting warmer.
The study compiled more than a billion temperature readings from global weather stations, plotting the global land temperature trend since 1800.
It showed that temperatures have indeed risen since the 19th century and that, since the mid 1950s, the average global land temperature has risen by around 1C.
The project was commissioned to resolve the dispute over previous findings, particularly in the wake of the 2009 'Climategate' affair, when hacked e-mails from the University of East Anglia suggested that global warming claims had been exaggerated.
The study produced similar conclusions to previous research by Nasa and the Met Office, together with the University of East Anglia, which indicated that global warming was happening.
“Our biggest surprise was that the new results agreed so closely with the warming values published previously. I was deeply concerned that the group [at UEA] had concealed discordant data".
The group's work also aimed to address claims from sceptical climate change bloggers about weather station data not showing a true warming trend. Sceptics claimed that higher temperature readings near cities skewed results from urban heat, but this research found that it did not significantly affect the averages because urban areas represent less than 1 per cent of the land on Earth.
"We have looked at these issues in a straightforward, transparent way, and based on that, I would expect legitimate sceptics to feel their issues have been addressed" Muller said.