Controversy-ridden UN climate panel has said it is reassessing another of its claim for linking global warming to an increase in the number and severity of natural disasters, bringing fresh embarrassment to it.

The latest criticism of the Intergovernmental Panel for Climate Change (IPCC) comes after the panel admitted its mistake in asserting that Himalayan glaciers could disappear by 2035.

The report also included another claim that rapidly rising costs from events such as floods and hurricanes were linked to climate change.

“We are reassessing the evidence and will publish a report on natural disasters and extreme weather with the latest findings. Despite recent events the IPCC process is still very rigorous and scientific,” The Sunday Times quoted professor Jean-Pascal van Ypersele, vice-chair of the IPCC as saying.

The newspaper claims that report, which won the panel a noble peace prize, was based on an unpublished paper that had not been subjected to routine scientific scrutiny.

When the paper was eventually published, in 2008, it said: “We find insufficient evidence to claim a statistical relationship between global temperature increase and catastrophe losses.”

Despite this change the IPCC did not issue a clarification ahead of the Copenhagen climate summit last month, the paper said.

Two scientific who checked drafts of the report had urged greater caution in proposing a link between climate change and disaster impacts, but were ignored.

The new controversy also goes back to the IPCC’s 2007 report in which a separate section warned that the world had “suffered rapidly rising costs due to extreme weather-related events since the 1970s“.

It said a part of this increase was due to global warming.

The academic paper at the centre of the latest questions was written in 2006 by Robert Muir-Wood, head of research at Risk Management Solutions, a London consultancy, who later became a contributing author to the section of the IPCC’s 2007 report dealing with climate change impacts.

Muir-Wood wanted to find out if the 8 per cent year-on-year increase in global losses caused by weather—related disasters.

He found from 1950 to 2005 there was no increase in the impact of disasters once growth was accounted for. For 1970-2005, however, he found a 2 per cent annual increase which “corresponded with a period of rising global temperatures.”

Muir-Wood was careful to point out that almost all this increase could be accounted for by the exceptionally strong hurricane seasons in 2004 and 2005.

Despite such caveats, the IPCC report used the study in its section on disasters and hazards, but cited only the 1970-2005 results.

Meanwhile, IPCC Chairman Rajendra Pachauri on Saturday said the UN body will use more rigorous research systems in the future.