Geoengineering: Likely or Loony?

Probably both:

The heavy industrial activity of the previous hundred years had caused the earth’s climate to warm by roughly three-quarters of a degree Celsius, helping to make the twentieth century the hottest in at least a thousand years. The eruption of Mt. Pinatubo, however, reduced global temperatures by nearly that much in a single year. It also disrupted patterns of precipitation throughout the planet. It is believed to have influenced events as varied as floods along the Mississippi River in 1993 and, later that year, the drought that devastated the African Sahel. Most people considered the eruption a calamity. For geophysical scientists, though, Mt. Pinatubo provided the best model in at least a century to help us understand what might happen if humans attempted to ameliorate global warming by deliberately altering the climate of the earth. For years, even to entertain the possibility of human intervention on such a scale—geoengineering, as the practice is known—has been denounced as hubris. Predicting long-term climatic behavior by using computer models has proved difficult, and the notion of fiddling with the planet’s climate based on the results generated by those models worries even scientists who are fully engaged in the research. “There will be no easy victories, but at some point we are going to have to take the facts seriously,’’ David Keith, a professor of engineering and public policy at Harvard and one of geoengineering’s most thoughtful supporters, told me. “Nonetheless,’’ he added, “it is hyperbolic to say this, but no less true: when you start to reflect light away from the planet, you can easily imagine a chain of events that would extinguish life on earth.” There is only one reason to consider deploying a scheme with even a tiny chance of causing such a catastrophe: if the risks of not deploying it were clearly higher. No one is yet prepared to make such a calculation, but researchers are moving in that direction.

We aren't going to kick our energy habit, and God forbid some fat Republican is ever forced to conserve energy, so we'll probably toy with the climate and try to unfuck it.  I get the feeling it would be a disaster to try it on a large scale.