None of the scientists in the room so much as blinked when David Keith suggested saving the world with spy planes spraying sulfuric acid.Keith, a physicist at the University of Calgary in Canada, was facing an audience not likely to be shocked: nearly 200 other researchers, some of whom had their own radical ideas for fighting global warming. His concept was to spray a mist of sulfuric acid high in the stratosphere to form particles called sulfate aerosols, which would act like a sprinkling of tiny sunshades for the overheating Earth.Keith’s idea may sound outrageous, but it is just one of m... (p. 16)