摘要：Any well‐informed future decision on whether and how to deploy solar geoengineering requires balancing the impacts (both intended and unintended) of intervening in the climate against the impacts of not doing so. Despite tremendous progress in the last decade, the current state of knowledge remains insufficient to support an assessment of this balance, even for stratospheric aerosol geoengineering (SAG), arguably the best understood (practical) geoengineering method. We articulate key unknowns associated with SAG, including both climate‐science and design questions, as an essential step toward developing a future strategic research program that could address outstanding uncertainties.
