We've successfully done this, to pretty decent success, once. In the north Atlantic.

Of course, the reflective material was an enormously harmful pollutant that was the reason for the entire acid rain crisis (anyone else remember how we used to have worldwide environmental crises that we would band together and solve? ah, memories).

I think the unfortunate reality is that part of the survival of our species is going to require this shit. And that it will, probably, cause major other problems -- we just have to hope they aren't worse than the ones being averted. It's going to happen. If by no one else, China or Saudi Arabia or some such will deploy the tech for selfish reasons. Better to be ahead of the R&D curve to make sure we have the best handle we can on what's going to happen with it.

Pretty much everyone on the science side of this, even the startups and researchers behind this tech, agree that we'd be better off not needing to use it. That it's a tragedy we're even considering it. But... it is. We're experiencing a global tragedy right now and need to be collectively realistic about it.