Obviously the fault of fossil fuels.
I’ve had some discussions with people about global warming. And I’ve run into unintelligible mutterring, when I point out facts, such as how Chicago was buried under ice during the last ice age, and the last ice age ended due to natural cycles of climate, not due to man’s pollution or man’s greenhouse gases.
I also get no intelligible response, to facts such as how there have been numerous ice ages in earth’s history, all of which were started and ended due to natural cycles we probably don’t understand.