I don't know the answer to this either, but I've seen this kind of compartmentalization in lots of very smart folks. I know a guy who's a brilliant optics engineer and has had success both in business and academia. He's not sold on climate change as a fact.
The fact that you used the word "sold" already implies to me its a matter of faith.
Climate change is a highly politicized and potentially corrupt push of an agenda. As Im not working on climate change or related sciences, all I can do is believe on what an alleged aggregate of scientist tell me, its pure faith.