As climate change becomes inevitable and at least a few degrees of future heating get "locked in", research is partially turning to the world of geoengineering - that is, planet-scale engineering, designed to directly undo the effects of global warming rather than merely trying to reduce carbon emissions.
Nobody really wants to do it of course, but it's often considered an inevitability as it seems people just aren't going to reduce emissions. Now, though, as it becomes quite a likely thing, some of the potential approaches are getting more attention - including what's probably the leading contender, global dimming.
The plan would be to pump sulfur compounds into the upper atmosphere where they reflect a small percentage of the Sun's rays, cooling the Earth. Having had a look at the plan, though, several scientists are rather concerned with how it would change weather patterns - including potentially eliminating monsoons in various regions (not a good thing), and how it would cause a rapid re-increase back to higher temperatures if we stopped.
Still, though, I think we're going to end up having to do some kind of geoengineering in the near future, if not only to stop over a billion people who live next to sea level from going homeless. I do think, though, just blindly dimming the whole planet maybe isn't it.