These crazy plans to reverse climate change didn't get Richard Branson's $25 million -- but they still might work

Grand solutions to the world's ever-sharpening threat of climate change are usually met with a mix of skepticism and fear. Geoengineering -- the practice of intervening with Earth's natural systems to stop global warming --is especially thought to be messing with fire. Take a dramatic action like spraying sulfate aerosols (water vapor and sulfur) into the atmosphere, increasing Earth's ability to reflect sunlight back into space, and we might be able to cool down the Earth. But global warming...