Well, here's the scary thing. If the idea pops into my dumbass head, you know it's popped in to theirs. You know that the scenario is on some list somewhere. They've probably even run simulations.

Here's the defining question, the truly frightening question. Have they determined to within a tiny faction of a kiloton what amount of nuclear yield it would take to correct global warming? Has anybody done that?

Have they simulated that yield being detonated at various places rather than one place?

If the answer is yes, then it's a work in progress.