A Startup's Bid to Dim the Sun

Summary

Advocates for geoengineering—or, at a minimum, of pursuing research into geoengineering—say that such risks impose obligations. They note that, since attempts to limit warming have failed, it’s incumbent on humanity to consider all the options. “If sunlight reflection could save lives and protect the environment, it is at least worth discussing,” David Keith and Zeke Hausfather, both climate scientists, wrote in a recent essay for the Times. “I don’t think we have the luxury of saying there are certain options we don’t explore and study,” Yedvab, the co-founder of Stardust, said. “Just as a metaphor, if there is one person in a household who’s in a crisis, you want to make sure that you have all the options in front of you of how to deal with this crisis.”The gloomy arguments for geoengineering are compelling. So are the even gloomier counter-arguments. Among the technology’s many possible side effects are shifts in regional weather patterns and the disruption of monsoons that hundreds of millions of people depend on. Since solar geoengineering would have global impacts, it would seem to demand that some sort of global agreement be in place before it could be deployed or even tested on a meaningful scale. But it’s hard to see how such an agreement could be reached, as conditions that benefit one region might very well flood or dry out another. Meanwhile, in the absence of such an agreement, there’s nothing to stop a powerful country, or group of countries, from utilizing the technology, except for the fear of disapproval (or that another country will shoot down their planes). A company called Make Sunsets is already selling “cooling credits” for lofting small quantities of sulfur dioxide into the stratosphere via balloons, though it is unclear whether this is having any effect on anything. Stardust says that it is committed to “comprehensive regulation of this emerging field, including governance mechanisms for the stratosphere”; so far, though, it has been moving a...