A counterfactual perspective on compound weather risk
Gordon Woo
Abstract
Extreme weather outcomes are a multi-dimensional function of interacting physical processes. Actual compound events correspond to particular specific historical realisations of these coupled processes. But due to their intrinsic stochastic nature, they might have led to different outcomes. Historical meteorological studies tend to focus on explaining what actually happened, rather than on considering the phase space of other possibilities. In contrast with extreme event catalogues, information about near misses and proximity to tipping points is not systematically collated. Consequently, stakeholder awareness of such high risk system states is limited. The exploration of alternative realisations provides a counterfactual perspective on compound weather risk, which broadens understanding of extreme weather events, especially in respect of severe impact consequences. This perspective would be an insightful supplement to statistical studies of extreme compound events.