Read all about the denial industry in the article below. Vested interested in a fossil fuelled economy are very affraid of the facts they know to be true - but which hurt their bottom line.
I doubt science has ever been so badly misused since the rise of nazism... except maybe for the tobacco industry's feeble attempts to make smoking seem harmless.
http://www.guardian.co.uk/climatechange/story/0,,1875760,00.html