Geoengineering as a Solution to Climate Change

Scientist Ken Caldeira makes the case for "geo-engineering" - shooting trillions of small particles of sulfate into the stratosphere as a way to reflect sunlight and cool the earth's temperature - as a last-ditch way to mitigate climate change without reducing carbon dixoide emissions. Such proposals are controversial - because the engineering problems are formidable, because sulfate is a harmful substance, and because of the fear that people will seize on geo-engineering as an excuse to ignore CO2 reduction. Nonetheless, I think Caldeira frames research into geo-engineering correctly - as an insurance policy that we ought to have in case we cannot resolve the economic and political challenges of controlling emissions.

The idea of geo-engineering first came to my attention through this WSJ article; it stuck in my mind because game theorist and Nobel laureate Thomas Schelling is a geo-engineering advocate (and presumably he knows a thing or two about collective action problems of the kind that bedevil climate agreements). Schelling briefly discusses the idea in his survey of climate policies here (see Kenneth Arrow's review of economics of climate change in same volume).