What Could Possibly Go Wrong: Blotting Out the Sun
Sun Shade Filling the stratosphere with sulfur aerosols could cool the globe, but it could also cause widespread drought and destruction Jamie SneddonGeoengineering could cause more problems than the global warming it aims to stop Engineering the atmosphere to forestall the worst results of global warming was once considered too hubristic to seriously contemplate. The grim prospects for passing an international climate-change treaty have changed that. Last year the National Academies of Science in the U.S. and the Royal Society in the U.K. both convened meetings on geoengineering. The schemes generally fall into two categories-CO2 capture (pulling carbon dioxide from the air) or solar-radiation management (reflecting sunlight)-but it's a form of the latter, which involves using airplanes or long hoses to pour sulfate aerosols into the lower stratosphere, that's the most audacious. Once in the stratosphere, the theory goes, the aerosols would reflect some solar radiation and prevent a devastating rise...