British Scientist Criticises US Climate "Loonies"

"The increased intensity of these kinds of extreme storms is very likely to be due to global warming," Lawton told the newspaper in an interview.

"If this makes the climate loonies in the States realise we've got a problem, some good will come out of a truly awful situation," said Lawton.

Less than a month after Hurricane Katrina devastated large areas of the US Gulf coast, a new hurricane called Rita was roaring through the Gulf of Mexico towards the centre of the US oil industry.

Climate change policies sharply divide Bush from many other world leaders who have signed up for caps on emissions of greenhouse gases under the UN's Kyoto protocol. Bush pulled out of Kyoto in 2001, saying it was too expensive and wrongly excluded developing nations from a first round of caps to 2012.

In July this year, Bush launched a six-nation plan to combat climate change with Australia, China, India, Japan and South Korea focused on a shift to cleaner energy technology. Unlike Kyoto, it stops short of setting caps on emissions.

Asked what conclusion the Bush administration should draw from two powerful hurricanes hitting the United States in quick succession, Lawton said:

"If what looks like is going to be a horrible mess causes the extreme sceptics about climate change in the US to reconsider their opinion, that would be an extremely valuable outcome.

"There are a group of people in various parts of the world ... who simply don't want to accept human activities can change climate and are changing the climate. I'd liken them to the people who denied that smoking causes lung cancer."

Lawton said hurricanes were getting more intense, just as computer models predicted they would, because of the rising temperature of the sea.

"Increasingly it looks like a smoking gun," he said.

"It's a fair conclusion to draw that global warming, caused to a substantial extent by people, is driving increased sea surface temperatures and increasing the violence of hurricanes."