Key Gaps in Models' Physical Representation of Climate Intervention and Its Impacts

Abstract

Solar radiation modification has been suggested as a potential method to reduce climate warming and its associated impacts, with three different types the subject of most research:stratospheric aerosol injection; marine cloud brightening; and cirrus cloud thinning. However, while modeling studies suggest some such methods could be effective, key challenges remain in accurately simulating their impacts due to complex interactions in aerosol physics, atmospheric chemistry, atmospheric dynamics, and aerosol‐cloud interactions that are inherent to the three SRM methods. We highlight critical research gaps that must be addressed to improve solar radiation modification modeling, including uncertainties in aerosol‐cloud interactions, aerosol microphysics, and their global effects. These gaps, identified by expert panels through the Geoengineering Modeling Research Consortium, emphasize the need for more detailed laboratory and field studies, along with improved models at multiple scales. We specifically outline where additional fundamental research is needed to support decision making around SRM, which will inevitably be made under uncertainty.