I'd say the masses dying of starvation and exposure would reduce global warming, but the millions of cars will be replaced by hundreds of private jets that net greater emissions.
The poor factory workers will be more destitute, and the rich will always find a way fill that void. Fuck, they will force their pilot to fly the empty jet around the world just to make sure that conditions on earth dont improve and they eventually get to utilize their vault 3 miles underground before they die.