Surely he jests...
I don’t know about the anthropogentic part, but I think it is pretty clearly accepted even by most skeptics that atmospheric CO2 has risen significantly in the past 100 years. I am not sure how expertise in Chemical Thermodynamics provides the expertise for his claims. Yes, climate changes, and in the 65 years I have been observing it, I would say that on the east coast of the US it has gotten warmer, especially in winter.