Thanks to Ruben for pointing us to this excellent piece  by Guardian columnist George Monbiot.
Monbiot offers a little sober second thought on the notion of broadcasting particles into the stratosphere to reflect enough solar energy to keep the world temperature manageable, despite the increased warming effect of rising CO2 levels.
There is something elegantly simple about the proposal to set up a particulate sunscreen; I found it reassuring when I first heard of a variation on this engineered solution from Gregory Benford  at the Skeptics Society conference at CalTech. But as Monbiot points out, by implication at least, human - nd even moreso, our governments - seldom get into trouble for the things that we do on purpose. It's the unintended, and usually unanticipated, consequences of our actions that always create the biggest problems.
Given the pace of warming and the risks, we certainly must continue to think about creative solutions. But there are questions to answer (and cars to park) before we start launching sunscreening particles into the atmosphere.