geo-engineering and "greenfinger"

​Geo-engineering is pretty scary business. 
The idea is to deliberately change the climate in order to combat all the incidental damage we’ve inflicted on the planet over the past few centuries. 
(This Atlantic article is a thorough and entertaining review of the major theories and issues, including at least two movie references and the words “commandeered” and “corset.”)
Some propositions from this colorful field of research are:
1. launching large mirrors into space to reflect sunlight away from the earth (guardian)
2. shooting millions of ceramic frisbees into the atmosphere out of mile-long guns for the same reason (atlantic)
3. pumping sulfur into the atmosphere, cooling the earth and turning the sky red, like in Bladerunner (atlantic)
This research is scary for two main reasons:
1. we would only be building a barricade– if any of the technology ever crashed, all of the CO2 we’d been deflecting would rush down upon us in one huge, catastrophic deluge. So if we’re ever going to do this, we need to learn to love that grainy, grimy atmosphere in bladerunner. 
2. it’s cheap– through geo-engineering, a single individual, a “greenfinger” as Stanford professor David Vitor puts it, could transform the entire world–potentially halting CO2 buildup, but definitely destroying the climate as we know it. 
So let’s jump on that carbon capture and algae fuel before it’s too late!