PNNL

Abstract

The last decade has seen broad exploratory research into stratospheric aerosol geoengineering, motivated by concern that mitigation alone may be insufficient to manage the impacts of climate change. This phase of research has not found any fundamental showstoppers: it is plausible that a limited deployment of geoengineering, provided it is used in addition to mitigation rather than as a supplement, could reduce many climate risks for most people. However, "plausible" is an insufficient basis on which to support future decisions. Developing the necessary knowledge requires a transition towards mission-driven research with the explicit goal of supporting informed decisions. We describe key features of this research, focusing on the physical-science questions, and articulate different phases of research.