I don't think "global warming zealots" exist, or that it's a religion. That seems like a dishonest caricature to me, and how anything seems when it's unclear to the layperson what makes it credible. Nor do I think the middle point between two extremes is always correct. 2+2=5 is in between 2+2=4 and 2+2=6, but that doesn't make it the most reasonable.

Confounding effects like the heat island effect, shade, albedo, etc. were what caused Richard A. Muller to also be skeptical of the findings AGW is based on. So, he re-did all of the original experiments while accounting for those factors. Notably, his funding came from the Koch brothers, who hoped he would find some flaw in the original methodology.

Can you guess what he found instead?