... said the guy who posted earlier that he didn't get that the term 'climate denier' was created to subconsciously link them to holocaust deniers.
The comparison between the two groups is apt. Both groups ignore the overwhelming, irrefutable facts for idealogical reasons. They deny the facts, and adopt a faith based position ("I don't believe the holocaust was real"), usually by vilifying the source of the facts ("Jews are evil, therefore the holocaust is a Zionist conspiracy"). In the case of global warming deniers, the argument is that leftists are forwarding an agenda, therefore it can't be real ("Al Gore is evil, therefore global warming is a left wing conspiracy").
Therefore, global warming deniers are just that - people who deny the facts based on their own belief system. As I said before, you can choose to believe what you want, you can believe the earth is flat, or that the moon is made of cheese, or that global warming isn't real, or that it isn't caused by mankind. But if you do, it is because you don't believe, not because of the facts. Because the facts prove you wrong.