If you want to prove them wrong, the data is available.
Put it this way, do you think that if the data supported those special interests who have paid a lot of money to discredit climate scientists that they wouldn't use it to actually do so?
The beautiful thing about science is that it doesn't care if you don't believe it, it simply is. The data is all there.
I still find it fascinating that people believe that one particular discipline of scientists - not all scientists, specifically one narrow discipline - is involved in a "pseudoreligious political" conspiracy.
What here is more likely? That they're right, or that 97% of all climate scientists on earth in every country, every university, every company, every government, every society are all in lockstep under some grand master plan to... what? Funnel small amounts of money to them?
Even if we take the ludicrous position that every government has decided to work together in perfect unison to run a grand conspiracy to generate tax money/green policy/some other right wing bogeyman de-la-jeure, how on earth are they going to keep all the scientists to go along with it? It sure isn't money - have you seen the salary of a scientist? The easy money is working for ExxonMobil or the Koch brothers. The money on the anti-climate-change side is vastly higher than it is on the "regular science" side. There's no way that 97% of scientists in the field would go along with it - all it would take is for one to be tempted by the dump truck full of cash to blow the conspiracy open, and that hasn't happened - despite all the attempts to discredit climate scientists.
It's not even as if the data they are using is somehow hidden. This is data collected globally from thousands of sources and hundreds and hundreds of people available to anyone who wants to study it.
The fact that you are classifying an entire discipline of science as "pseudoreligious" says it all really. You disagree with 97% of scientists on this issue, but you're not sure why (or you lack the arguments as to why) except that you've been told they are all involved in some conspiracy, so you make it into some political ideology battle.
I guess I should trust the 3% of programmers who say that there are NSA backdoors in the Linux kernel. I mean, some guy on 4chan said it and I believe him. Those pseudoreligious zealots on slashdot are just trying to get me to use Linux so the government can spy on me.