Global warming is the fantasy.
Cooling and warming cycles are definite, everytime the ice melted it released dissolved and trapped CO2 into the atmosphere.
It is the warming which releases CO2 , not CO2 which canuses warming.
They have never been able to prove which drove what, but ice core data are ademment as well as basic physics. Warm water boils out disolved gases in the air. Ice cubes are cloudy because the gas is pushed towards the core, or downward and underneath in ice lakes, stored away naturally.
Denver used to be under water and there was nothing we could have done to prevent it drying out.