Arthur C. Clarke wrote a sequel to the sequel to the sequel of 2001 (called 3001) where Frank Poole is rescued a thousand years after been lost in orbit around Jupiter/Saturn. By then global warming isn’t caused by carbon dioxide or methane or even water vapor. It’s from 1,000+ years of waste heat generated by each human that’s ever lived. Even with 100% clean energy, everything still creates heat, and it has to go somewhere.