Even if they can be a major disaster for people nearby them, volcanoes do one good thing: helping to cool the planet by sending sun-reflecting chemicals into the stratosphere. Now two Harvard engineers are trying to replicate the better part of the volcanic process on a small scale by spraying thousands of tons of sulfate aerosols into the atmosphere above New Mexico.
Within a year, the researchers, David Keith (who manages a multimillion dollar geoengineering research fund from Bill Gates) and James Anderson, will release the chemicals from a balloon 80,000 feet above Fort Sumner, then measure the effects on the ozone's chemistry. (To answer the big question: no, this can't be pulled off in a lab.) This will be a test, not a full-on attempt to stop climate change, the researchers say, and it won't have any major effects on the environment.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.