There is no denying that Global Warming exists. It is just unproven that man is the cause of it.
I don't know of anyone who says that man has NO role (at least on this thread), but science supports that there is no proof that man contributes to Global Warming. IMO, it's extremely arrogant to think that we can have that kind of effect on the planet. It will be here long after we are gone. We're like a mild case of eczema.