Not, like, initiating a full-scale manipulation of the stratosphere next week, but at least looking into the idea. “It’s very important that we understand what our tools are,” he says. “What options do we have? How much risk is there?”
The options are few and the risks murky. Take, for instance, sulfur seeding. The idea is to inject sulfur dioxide into the lower stratosphere, where it turns into sulfur aerosol that reflects light back into space. Problem is, just last month researchers released a study showing that if you injected the stuff into the Northern Hemisphere, you might reduce hurricanes in the Atlantic—and kick off a drought in north-central Africa in the process.