I don’t know about whether human activity has any effect on climate. What I do know is that:
a.) The climate has been changing cyclically since the beginning of time.
b.) There is a lot more money to be made convincing the rubes that it is their fault than in allowing them to believe it is caused by natural events beyond anyone’s control.
c.) If enough of the rubes can be convinced climate change is caused by Western Civilization, they will vote themselves back into serfdom and servitude in order to “Save the planet”.
Could some people be suffering from “climate guilt”? Prius and tesla come to mind. I’m sure there are more like the volt. Me, being a denier means crankin’ up the Hemi.