[folkrav]

Do I need to hold the opinion that water is wet for it to be factual?

To answer your question, if by climate change you refer to the dramatic post-industrialisation acceleration of warming and climate disturbances, the correct answer is "the overwhelming majority of existing evidence points to yes".

[what]

Is water wet though? It’s the substance that makes other things wet, but is it wet itself?

[folkrav]

If we go full on aykchyually on this, technically no, sure. I however assume most English speakers would be familiar with the idiom lol