Survey And Comparison Of In-Space And In-Atmosphere Geoengineering Concepts For Climate Change Mitigation

We believe reversible in-space approaches for geoengineering provide promising answers for direct climate action from space. Our paper surveys, analyzes, and compares previously proposed geoengineering concepts for possible Climate Change Mitigation endeavors that could be conducted from space-based or Earth-based systems and methods. The goal of our work is to foster discussions involving engineers, scientists, international law experts and decision makers, and to provide a baseline reference for further studies. We conclude that recent advances in commercial heavy space launchers warrant more tangible considerations of in-space geoengineering. In-space geoengineering (a planetary sunshade) has the potential to develop fully reversible technologies that conserve humanity’s ‘one atmosphere’, while achieving near perfect capacity for the alteration of solar radiation. We provide a detailed cost analysis for a sunshade mission and propose that the deployment cost of planetary sunshade technology could fall within a comparable order of magnitude to global estimates given for mitigation investment flows that are necessary to address global warming.