Rajendra Pachauri, the head of the international body which produces key reports to advise governments on climate change, today defended the use of "grey literature" which is not published in scientific journals.
The Intergovernmental Panel on Climate Change (IPCC) has come under fire after a high-profile mistake was exposed in its most recent assessment of the scale and impacts of global warming — a claim the Himalayan glaciers would melt by 2035.
The claim came from a report by charity WWF and was based on remarks made by an Indian scientist which were never published in a scientific, peer-reviewed journal.
The IPCC has said it regretted the mistake, revealed at the height of the row over climate science which blew up amid efforts to secure a new global agreement to tackle rising greenhouse gas emissions.
In a hearing today of the InterAcademy Council, an organisation of the world's science academies which is conducting an independent review of the processes and procedures of the IPCC, Pachauri described the inclusion of the glacier claim as "human failure" which should not have happened.
But the IPCC's chairman said there was a need to use information which was not from peer-reviewed scientific journals, because in some places that was the only research that had been done.
He said the media and other sections of society had misunderstood the role of such information, labelling it grey literature, "as if it was some form of grey muddied water flowing down the drains".
Dr Pachauri said academic work being done by bodies including the International Energy Agency, the World Bank, national governments and charities "cannot be ignored", but had to be closely examined to make sure it was robust.
He said there had been comments from contributors before publication but "they were not very specific in this regard".
He told the hearing in Amsterdam: "Somehow it just missed everybody's attention.
"It is in my view a human failure which happened a few times, we just have to make sure something like this doesn't happen once again."
Dr Pachauri said the mistake was buried in the 1,000 page report and did not get used in the much-shorter summary which is written for use by policy-makers.
And he said: "We have been less than adequate in informing the public that, yes, there was an error but that does not take away anything from the fact the glaciers are melting at a very rapid rate.
"This is where our communication skills need to be enhanced."
Even if the Himalayan glaciers did not melt by 2035, glaciers around the world were in decline, with water supplies predicted to fall and the melting ice contributing to sea level rises, he said.
"Although there was this error, there's a whole lot of valid information and assessment on glaciers which we can only ignore at our own peril and the peril of generations yet to come," he said.