So I present you this. What we have here is something exceedingly common, and something that I have recently talked about. We have a decrease amongst those who accept the current climate change as man- made. As such, there has also been a increase in those who believe that there is not consensus as to the cause of the global warming within the scientific community (especially climate and geologic-based sciences).
Why do we have this negative trend of (un) acceptance? We see that there has been a shift from complete denial that the world's climate is changing, to the attitude that we are not to blame. The leading counter- argument is thus: We don't know enough about CO2 levels to conclude that it is playing a part in the green house effect.
Never mind that since 1861 we have known about the absorption of long wave radiation by CO2. Forget mountains of evidence we have staring not only us, but future generations of stubborn assholes in the face. Never mind that we have numbers screaming at us, telling us that green house gases do in fact have an effect on global warming.
We live in a free country. We don't have anyone dictating what we believe, nor what information we have access to. So when I see someone actively denying global climate change, and our role in it, I see a fool. To deny the work of so many hard working scientists, is to be not only willfully ignorant, but arrogant to the highest degree. Dunning- Kruger. Look it up.