Tinfoil!
If we really believed Global Warming was true and a problem, we could spew millions of flakes of really small tinfoil into orbit, deflecting sun rays.
Stupid idea (since GW is a fraud), but I’ve heard of scientists who believe it would work.
Just have all the tinfoil hats put the shiny side out and reflect all that sunlight (as well as have alien mind probes deflected).