I did a two-year post-doc in a climate modeling lab at a major research university studying exactly this proposal. I have peer-reviewed publications on it. I cannot overstate what a bad idea it is. It would kill--at minimum--tens of millions of people, and set off the worst refugee crisis the world has ever seen as global precipitation patterns shifted--and those are the effects we know about. Once we start it, we will have to run it indefinitely or incur absolutely apocalyptic snap-back temperature increases.
Still, I will be absolutely flabbergasted if we don't implement this sometime in the next 15 years. It's cheap, effective at controlling temperature increases, and will let us continue to kick the can down the road for meaningful climate action.