It is real, but it has not too much to do with CO2-levels, and the idea that "saving" CO2 can change the course of the climate, is lunatic. In the past we had cycles of climate changes than span 1000s of years with no fossile combustion cars, etc. Ask the "experts" how they explain these changes :) They won´t know (or won´t admit that the sun has something to do with it), so why they are so certain about what to do now?
The climate change discourse is more about control of people and their habits than about their influence on climate change, imo.
Maybe the cows from that time had something to do with it, lol. Like a mass bad stomach for centuries, or something like that...