Although there is an important role for scepticism in science, for almost 30 years some corporations have supported a disinformation campaign about climate change science.

While it may be reasonable to be somewhat sceptical about climate change models, these untruths are not based upon reasonable scepticism but outright falsification and distortions of climate change science.

These claims have included assertions that the science of climate change has been completely "debunked" and that there is no evidence of human causation of recent observed warming. There are numerous lines of evidence that point to human causation even if it is not a completely settled matter. Reasonable scepticism cannot claim that there is no evidence of causation and some other claims frequently being made by the well-financed climate change disinformation campaign, and they amount to an utter distortion of a body of evidence that the world needs to understand to protect itself from huge potential harms.... 

Read the full article here: http://www.guardian.co.uk/environment/cif-green/2010/nov/01/climate-science-disinformation-crime