think that obviously has to be recognised as a factor >>> one strong anti-regulation voice is dr patrick michaelsctor of the center for the study of science at the cato institute. this libertarian think-tank was co-founded by charles koch in 1974. today, koch and his brother david head koch industries one of the largest private companys in america. through their company and foundations they donate to politicians and issues surrounding the fossil fuel industry. >>> let's start really simply, does climate change exist? >> of course, climate change has existed since the earth got an atmosphere. >> is climate change manmade. >> some of it has a human cause, that's correct. >> but michaels is among a group of scientist cited by senator inhofe that believe the worsening climate change models are wrong. >> i would argue that every model that we have - i wouldn't argue, these are facts, okay. shows that if we drop our emissions to zero, we don't do anything really detectable over the course of 100 years. that's incontrovertible reality coming from our own environmental protection agency's models. >> that