Scott Aaronson's response to Lubos Motl's skepticism is informative:
"My position is an incredibly simple one: just like with the link between smoking and cancer, or the lack of a link between vaccines and autism, or any other issue where I lack the expertise to evaluate the evidence myself, I’ll go with what certainly looks like an overwhelming consensus among the scientists who’ve studied the matter carefully. Period. If the climate skeptics want to win me over, then the way for them to do so is straightforward: they should ignore me, and try instead to win over the academic climatology community, majorities of chemists and physicists, Nobel laureates, the IPCC, National Academies of Science, etc. with superior research and arguments.
"To this, the skeptics might respond: but of course we can’t win over the mainstream scientific community, since they’re all in the grip of an evil left-wing conspiracy or delusion! Now, that response is precisely where “the buck stops” for me, and further discussion becomes useless. If I’m asked which of the following two groups is more likely to be in the grip of a delusion — (a) Senate Republicans, Freeman Dyson, and a certain excitable string-theory blogger, or (b) virtually every single expert in the relevant fields, and virtually every other chemist and physicist who I’ve ever respected or heard of — well then, it comes down to a judgment call, but I’m 100% comfortable with my judgment."
https://www.scottaaronson.com/blog/?p=1307