They are the latest in a series of damaging revelations about the IPCC’s most recent report, published in 2007.
Last month, the panel was forced to issue a humiliating retraction after it emerged statements about the melting of Himalayan glaciers were inaccurate.
Last weekend, this paper revealed that the panel had based claims about disappearing mountain ice on anecdotal evidence in a student’s dissertation and an article in a mountaineering magazine.
And on Friday, it emerged that the IPCC’s panel had wrongly reported that more than half of the Netherlands was below sea level because it had failed to check information supplied by a Dutch government agency.
Researchers insist the errors are minor and do not impact on the overall conclusions about climate change.
However, senior scientists are now expressing concern at the way the IPCC compiles its reports and have hit out at the panel’s use of so-called “grey literature” — evidence from sources that have not been subjected to scientific scrutiny.
A new poll has revealed that public belief in climate change is weakening.The panel’s controversial chair, Rajendra Pachauri, pictured right, is facing pressure to resign over the affair.
The IPCC attempted to counter growing criticism by releasing a statement insisting that authors who contribute to its 3,000-page report are required to “critically assess and review the quality and validity of each source” when they use material from unpublished or non-peer-reviewed sources. Drafts of the reports are checked by scientific reviewers before they are subjected to line-by-line approval by the 130 member countries of the IPCC.
Despite these checks, a diagram used to demonstrate the potential for generating electricity from wave power has been found to contain numerous errors.
The source of information for the diagram was cited as the website of UK-based wave-energy company Wavegen. Yet the diagram on Wavegen’s website contains dramatically different figures for energy potential off Britain and Alaska and in the Bering Sea.
When contacted by The Sunday Telegraph, Wavegen insisted that the diagram on its website had not been changed. It added that it was not the original source of the data and had simply reproduced it on its website.
The diagram is widely cited in other literature as having come from a paper on wave energy produced by the Institute of Mechanical Engineering in 1991 along with data from the European Directory of Renewable Energy.
Experts claim that, had the IPCC checked the citation properly, it would have spotted the discrepancies.
It can also be revealed that claims made by the IPCC about the effects of global warming, and suggestions about ways it could be avoided, were partly based on information from ten dissertations by Masters students.
One unpublished dissertation was used to support the claim that sea-level rise could impact on people living in the Nile delta and other African coastal areas, although the main focus of the thesis, by a student at the Al-Azhar University in Cairo, appears to have been the impact of computer software on environmental development.
The IPCC also made use of a report by US conservation group Defenders of Wildlife to state that salmon in US streams have been affected by rising temperatures. The panel has already come under fire for using information in reports by conservation charity the WWF.
Estimates of carbon-dioxide emissions from nuclear power stations and claims that suggested they were cheaper than coal or gas power stations were also taken from the website of the World Nuclear Association, rather than using independent scientific calculations.
Such revelations are creating growing public confusion over climate change. A poll by Ipsos on behalf of environmental consultancy firm Euro RSCG revealed that the proportion of the public who believe in the reality of climate change has dropped from 44 per cent to 31per cent in the past year.
The proportion of people who believe that climate change is a bit over-exaggerated rose from 22 per cent to 31per cent.
Climate scientists have expressed frustration with the IPCC’s use of unreliable evidence.
Alan Thorpe, chief executive of the Natural Environment Research Council, the biggest funder of climate science in the UK, said: “We should only be dealing with peer-reviewed literature. We open ourselves up to trouble if we start getting into hearsay and grey literature. We have enough research that has been peer-reviewed to provide evidence for climate change, so it is concerning that the IPCC has strayed from that.”
Professor Bob Watson, who chaired the IPCC before Dr Pachauri and is now chief scientist at the Department for Environment, Food and Rural Affairs, insisted that despite the errors there was little doubt that human-induced climate change was a reality.
But he called for changes in the way the IPCC compiles future reports.
“It is concerning that these mistakes have appeared in the IPCC report, but there is no doubt the earth’s climate is changing and the only way we can explain those changes is primarily human activity,” he said.
Mr Watson said that Dr Pachauri “cannot be personally blamed for one or two incorrect sentences in the IPCC report”, but stressed that the chairman must take responsibility for correcting errors.
Another row over the IPCC report emerged last night after Professor Roger Pielke Jnr, from Colorado University’s Centre for Science and Technology Policy Research, claimed its authors deliberately ignored a paper he wrote that contradicted the panel’s claims about the cost of climate-related natural disasters.
A document included a statement from an anonymous IPCC author saying that they believed Dr Pielke had changed his mind on the matter, when he had not.