Smithsonian: Installing a giant mirror in space to block sunlight, dispersing mass quantities of minerals into the oceans to suck carbon dioxide from the air and infusing the Earths upper atmosphere with sun-reflecting chemicals might sound like the stuff of science fiction, but theyre actual techniques that have been contemplated by scientists as possible quick solutions to climate change. More specifically, theyre examples of geo-engineering, a hotly contested subset of climate science whereby the Earths...