One of the world's foremost meteorologists has called the theory that helped Al Gore share the Nobel Peace Prize "ridiculous" and the product of "people who don't understand how the atmosphere works".

Dr William Gray, a pioneer in the science of seasonal hurricane forecasts, told a packed lecture hall at the University of North Carolina that humans were not responsible for the warming of the earth.

His comments came on the same day that the Nobel committee honoured Mr Gore for his work in support of the link between humans and global warming.

"We're brainwashing our children," said Dr Gray, 78, a long-time professor at Colorado State University. "They're going to the Gore movie [An Inconvenient Truth] and being fed all this. It's ridiculous."

At his first appearance since the award was announced in Oslo, Mr Gore said: "We have to quickly find a way to change the world's consciousness about exactly what we're facing."

Mr Gore shared the Nobel prize with the United Nations climate panel for their work in helping to galvanise international action against global warming.

But Dr Gray, whose annual forecasts of the number of tropical storms and hurricanes are widely publicised, said a natural cycle of ocean water temperatures - related to the amount of salt in ocean water - was responsible for the global warming that he acknowledges has taken place.

However, he said, that same cycle meant a period of cooling would begin soon and last for several years.

"We'll look back on all of this in 10 or 15 years and realise how foolish it was," Dr Gray said.

During his speech to a crowd of about 300 that included meteorology students and a host of professional meteorologists, Dr Gray also said those who had linked global warming to the increased number of hurricanes in recent years were in error.

He cited statistics showing there were 101 hurricanes from 1900 to 1949, in a period of cooler global temperatures, compared to 83 from 1957 to 2006 when the earth warmed.

"The human impact on the atmosphere is simply too small to have a major effect on global temperatures," Dr Gray said.

He said his beliefs had made him an outsider in popular science.

"It bothers me that my fellow scientists are not speaking out against something they know is wrong," he said. "But they also know that they'd never get any grants if they spoke out. I don't care about grants."