By Ben Webster | Times Online | Feb. 25, 2010

The two most influential advisory bodies on climate change are planning independent reviews of their research in an attempt to regain public trust after revelations about errors and the suppression of data.

The Intergovernmental Panel on Climate Change is to appoint an independent team to examine its procedures after admitting having made errors that exaggerated the severity of the impact of global warming.

The Met Office, which supplies the global temperature trends used by the IPCC, has proposed that an international group of scientists re-examine 160 years of temperature data. The Met Office proposal is a tacit admission that its previous reports on such trends have been marred by their reliance on analysis by the University of East Anglia’s Climatic Research Unit.

Two separate inquiries are being held into allegations that the unit tried to hide raw data from critics and exaggerated the extent of global warming.

In a document entitled Proposal for a New International Analysis of Land Surface Air Temperature Data, the Met Office says: “We feel it is timely to propose an international effort to re-analyse surface temperature data in collaboration with the World Meteorological Organisation.”

The new analysis would test the conclusion reached by the IPCC that “warming of the climate system is unequivocal”. The IPCC’s most glaring error was a claim that all Himalayan glaciers would disappear by 2035. Most glaciologists believe it would take another 300 years for the glaciers to melt at the present rate.

The allegations about climate scientists are believed to have contributed to a sharp rise in public scepticism about climate change. This month an opinion poll found that the proportion of the population that believes climate change is an established fact and largely man-made has fallen from 41 per cent in November to 26 per cent.

The Met Office paper emphasises that the assessment would be independent and based on data freely available to the public. It says: “The proposed activity would provide a set of independent assessments of surface temperature produced by independent groups using independent methods.”

The Met Office privately proposed the reassessment last December, soon after more than a thousand leaked e-mails raised doubts about the integrity of some scientists at the Climatic Research Unit. The Times revealed on December 5 that the Department of Energy and Climate Change had stopped the Met Office announcing the reassessment because it feared that it would be seized upon as an admission of weakness on the eve of the Copenhagen climate summit.

The reassessment will look at the data in much greater detail than previous attempts and provide more information about which regions are suffering extreme heat waves and the greatest average changes in climate. The Met Office said that this would allow international funding to be directed to where it was most needed.

Data from 3,000 weather stations around the world has already been published on the Met Office website and it hopes that data from the remaining 2,500 will be available later this year.

The paper states that the reassessment is intended chiefly to “ensure that the datasets are completely robust and that all methods are transparent”.

The Met Office says that it does not expect “any substantial changes in the resulting global and continental-scale multidecadal trends”.

It said that the reassessment would take up to three years. It hopes the findings will be ready for the IPCC’s next report, to be published in 2013 and 2014.