A risk-risk assessment framework for solar radiation modification

Concern about the increasingly high-probability, high-impact risks posed by global warming is driving the exploration of new techniques to artificially cool the planet through an approach known as solar radiation modification (SRM). Would the world be better off with or without such techniques? Would there be winners and losers? And how can we sufficiently compare the relative risks presented in a future with SRM against the risks faced in a future without it? Such ‘risk-risk’ assessment poses particular challenges given uncertainties around the techniques and the extent of human-induced changes to the climate system that might be expected in the future. These uncertainties are further compounded by differences in stakeholders’ framing and risk tolerance, as well as the level of complexity and the intertemporal nature of such assessment. To help address these questions, mindful of such challenges, we present here a basic risk-risk assessment framework providing a structure to help strengthen risk-management considerations in the design of future climate response strategies.