OSLO - Evidence that humans are to blame for global warming is rising but governments are doing too little to counter the threat, the head of the United Nations climate panel said on Monday.

Rajendra Pachauri, chairman of the Intergovernmental Panel on Climate Change (IPCC), also said that costs of braking climate change in coming decades might be less than forecast in the IPCC's last report in 2001.

"If one looks at just the scientific evidence that's been collected it's certainly becoming far more compelling. There is no question about it," he told Reuters of research since 2001 into a link between human emissions of greenhouse gases and rising temperatures.

Pachauri was more forthright than at the last U.N. climate meeting in Montreal, Canada, in December, when he declined to say whether there was clearer scientific evidence that human activities were to blame.

The last IPCC report in 2001 said there was "new and stronger evidence" that gases released by burning fossil fuels in power plants, factories and cars were warming the planet.

Warming may herald catastrophic climate changes such as more heatwaves, droughts, floods and rising sea levels.

The IPCC, grouping research by about 2,000 scientists, will present its next report to the United Nations in 2007. The report is the mainstay for environmental policy-making.

Still, Pachauri said it was too early to draw exact conclusions.

A BBC report last week said the IPCC would say in 2007 that "only" greenhouse gas emissions can explain freak weather patterns. "That's premature because the report is still nowhere near completion," he said.

MORE ACTION

Pachauri said the world needed to do more.

"Given the gravity of the situation and the importance of taking action I hope that the global community will move a little more rapidly with some future agreements," he said.

The U.N.'s Kyoto Protocol, which obliges industrial nations to cut greenhouse gas emissions, entered into force last year after years of wrangling and weakened by a U.S. pullout.

Pachauri said people living in island states such as the Maldives in the Indian Ocean, Tuvalu in the Pacific or low-lying countries such as Bangladesh were among those most at risk.

"They are living in a state of fear," he said. "We must understand the reasons behind their fears. We're really talking about their very existence, the complete devastation of the land on which they're living."

And cities from New York to Shanghai, from Buenos Aires to London, could also be swamped by rising seas.

The IPCC report says that costs of curbing greenhouse gases in the toughest case could delay world growth from reaching projected 2050 levels until 2051 or 2052.

"That's not a heavy price to pay," he said in a speech at Oslo university. "Personally I think these (IPCC) projections are pessimistic."

He said more U.S. companies, cities and states were acting to cap greenhouse gas emissions even though President George W. Bush pulled the United States out of Kyoto in 2001, saying it was too costly and wrongly excluded developing nations.

"I think (U.S. action) is going to gather momentum," he said. He noted that even Bush had said in January that the United States was "addicted to oil".

© Copyright 2006 Reuters Ltd

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