A NOAA scientist in Boulder, Daniel Murphy, recently published a study on the effect that geoengineered sulfur injections in the atmosphere would have on incoming solar radiation. He finds that incoming photons are three times more likely to diffuse and scatter rather than reflect (reflection is responsible for cooling effects). Dr. Murphy also calculated the potential effect this would have on solar power plants. Because solar collectors can only utilize direct solar radiation, Murphy predicts as much as a 20% decrease in solar productivity from solar panels (for details see links below). He also points out that low-budget energy saving efforts like south-facing windows would be less effective with sulfur geoengineered cooling due to the decine in direct sunlight.
These findings, aside from being interesting, show how important it is to have a diverse, interdisciplinary approach to examine the effects of geoengineering. For any type of geoengineering, the entire earth is affected. It behooves governments to encourage (fund) research on the possible and probable outcomes from ecological, atmospheric, energetic and every other kind of scientific standpoint around. To tie into the post before this, maybe extra government funding and time is needed for enough research to make an IPCC-esque panel on geoengineering possible. While it requires the luxury of time to allow the research to develop naturally, it seems that it would be much more thorough than the multiple, independent, focused groups that Victor proposed were needed to tackle the issue. For the great uncertainties in geoengineering to be fully studied a Manhattan Project would not be effective. There are simply too many disciplines, too many unknowns, and no common goal or end in sight. Merely the acquisition of knowledge, which seems able to be handled by our current R&D infrastructure.