As scores of people around the world embraced the green-living spirit embodied by Live Earth festivities, one filmmaker couldn't help but voice his skepticism towards the environmental movement.

Global warming is nothing more than the earth's natural flow towards varying temperatures, according to Martin Durkin, the filmmaker behind the documentary, "The Great Global Warming Swindle."

He directed the documentary to rebut Al Gore's film, "The Inconvenient Truth", a testament to the earth's rapid demise at the hands of the public's environmentally-dismissive actions.

On the documentary's website, some of the arguments made against global warming are noted.

"Those who think global warming is a natural process point to the fact that in the last 10,000 years, the warmest periods have happened well before humans started to produce large amounts of carbon dioxide." it says. "There is some evidence to suggest that the rise in carbon dioxide lags behind the temperature rise by 800 years and therefore can't be the cause of it."

When Durkin appeared on Â鶹´«Ã½net on Saturday, the day the Live Earth concerts took place, he ridiculed the event, calling it hypocritical and ignorant.

"I think it's a combination of hypocrisy and ignorance because the idea of Al Gore and Madonna telling us the world is consuming too much makes the mind boggle," he said. "But ignorance because so few people are prepared to actually look at the evidence and there is so much evidence now that flatly contradicts the notion of man-made global warming.

"I think this is political prejudice rather than science," he continued.

Reports released by the Intergovernmental Panel on Climate Change earlier this year, which represent the consensus opinion of more than 120 governments, found that global warming is real and that human activities, most notably the burning of fossil fuels, are more than 90 per cent likely to be the cause.

One Toronto professor dismissed Durkin's documentary -- which hasn't found much favour in the scientific community -- and said the arguments he makes have long been settled.

"The climate is warming and humans are the cause of it. Natural cycles play a very minor role, if any," said Danny Harvey, a geography professor at the University of Toronto.

"If the warming continues, we're in big trouble. That -- and that's the scientific argument -- has been settled quite some time ago."

Harvey told Â鶹´«Ã½net he was happy Live Earth was more than just an excuse to rock and roll. He said concerts with positive messages like this one have an impact on their audience.

"I tuned into this morning before coming into the studio and I was pretty impressed with the messages and the information in between the various gigs by the various superstars and I think it's making a contribution to getting the message across," he said.

Harvey also said Live Earth shouldn't be criticized for not being a completely green event, but instead people should be focusing on the fact the world-wide event was able to mobilize a global public.

"Everything we do has a negative effect but some things have a greater negative effect than others," he said. "I think we need to look at the bigger picture in the longer term which is to mobilize public pressure for serious action by governments and we're not seeing serious action yet. Also, increasing the awareness of what we can do as individuals."