Hacking the atmosphere: Geoengineering gets a reality check

Jim Franke, a research assistant professor at the University of Chicago, is developing aircraft designs for solar geoengineering, a controversial concept aimed at artificially cooling the planet by reflecting sunlight into space. Franke's proposed uncrewed aircraft features massive wings designed to fly in the stratosphere, approximately 20 kilometers above Earth's surface, where the air is significantly thinner. This altitude is crucial for releasing materials that could mimic the temperature-reducing effects of large volcanic eruptions, which have historically injected sulfur dioxide and other compounds into the stratosphere, forming sunlight-scattering particles. While climate models suggest solar geoengineering could be effective, Franke highlights significant engineering challenges that computer simulations do not fully address. These include the current lack of aircraft capable of carrying the required payloads to such high altitudes and uncertainties in the precise methods for releasing materials to ensure they form reflective aerosols rather than clumping and falling out of the atmosphere. Franke's work focuses on overcoming these practical hurdles to make solar geoengineering a viable near-term option.