Hacking the atmosphere: Geoengineering gets a reality check
Why this matters: a development in AI with implications for how people work, create, and decide.
Jim Franke pulls away the cover page of a presentation on the wraparound desk in his office, revealing an illustration of an odd-looking aircraft with massive wings stretching out from a stubby fuselage. The uncrewed plane is soaring thousands of meters higher than commercial jets fly—so high you can see the curvature of the Earth. It’s precisely the type of aircraft one would need to begin artificially cooling the planet. Those outsize wings would keep the plane and its payload aloft in the stratosphere, about a dozen miles (or 20 kilometers) above the surface, where the air is much thinner—as little as 5% the density near the ground. Once at altitude, the plane would release materials that could, after a few steps of chemistry, reflect sunlight back into space. “If you want to get to 20 kilometers in the near term, this is probably the best bet,” says Franke, a research assistant professor at the University of Chicago. Franke is one of a small but growing cohort of scientists focused on the engineering challenges associated with solar geoengineering, the controversial idea that we could deliberately intervene in the climate system to counteract global warming. The concept came from volcanoes. Massive eruptions in the past have reduced temperatures worldwide by blasting sulfur dioxide and other compounds into the stratosphere, where they convert into sunlight-scattering particles. Hundreds of studies in recent decades have suggested that a human attempt to mimic this mechanism would work quickly and efficiently—at least within the confines of climate models. But these computer simulations are approximations of how the real world works. They gloss over numerous challenges. Like the fact that aircraft capable of carrying the necessary loads to the necessary altitudes don’t exist. Or that we don’t know for sure how to release material so that most of it turns into tiny reflective aerosols instead of, say, clumping together and falling out of the sky. Or even what spe