Between the sun and us: Expert perceptions on the innovation, policy, and deep uncertainties of space-based solar geoengineering.

Space-based geoengineering is gaining attention, if not necessarily traction, as a possible "break the glass" solution to mitigate the worst impacts of climate change and facilitate the transition to a low-carbon future. Though still on the periphery of discussions around climate mitigation and geoengineering, space-based methods that would deflect or block incoming sunlight, and thereby diminish how much radiation ultimately reaches the Earth, could offer advantages, notably, by avoiding the need for difficult trade-offs and decisions in terms of land and resource use on Earth. Aside from a few specialist-oriented studies, the literature on space-based geoengineering remains limited. In this study, we utilize a large and diverse expert-interview exercise (N = 125) to provide a first critical examination of the promise and relevance of space-based geoengineering for tackling climate change, including perhaps as a source of renewable energy, its feasibility and prospective risks, as well as key actors and issues related to commercialization and governance. To our knowledge, no other study has employed empirical data of any kind to examine perceptions of space-based geoengineering, let alone in relation to other kinds of climate-intervention technologies. Not only does the current research represent the first of its kind, it also provides a foundation for more informed, comprehensive deliberations around this interesting, possibly even necessary solution to climate change. • Space-based solar geoengineering is a radical proposal for tackling climate change. • No study has so far employed empirical data to explore perceptions of space-based proposals. • Our data is derived from a diverse set of 125 original interviews with key experts. • The promise, feasibility, and risks for climate mitigation are critically examined. • We also engage with the potential of sunshades to provide significant amounts of renewable energy. [ABSTRACT FROM AUTHOR]