The planet is hot and getting hotter. But while most plans to use geoengineering to alter the weather have been rather hypothetical, now a pair of Harvard engineers have announced that they intend to spray thousands of tons of particles into the sky to block the suns rays—within the coming year.The pair plan to launch a balloon to ascend 80,000 feet over Fort Sumner, New Mexico, before pumping out tens or hundreds of kilograms of sulphate aerosols into the sky. The idea is that the particles will reflect sunlight back into space, helping decrease the temperature of the Earth.

via Scientists Plan to Block the Sun Using Man-Made Clouds.