Increasing Preparedness for Extreme Events using Plausibility-Based Scenario Planning: Lessons from COVID-19.

A striking feature of COVID-19 is many countries' low level of preparedness for it, despite pandemics being a known threat. This raises a question as to the reasons for this underpreparedness. While preparedness should have better reflected pandemics' long-run inevitability and potentially catastrophic impact, government-planning horizons are short term, and the attentiveness of policymakers is bounded and subject to multiple demands. Preparedness is therefore affected by the fundamental uncertainty surrounding the exact nature, timing, and impact of a pandemic. While a subjective probability is attributable to such an event's occurrence, just like it is any other, if founded on scant knowledge and perceived as being low it may inhibit preparedness. Under such circumstances, preparedness may be better served by a focus on plausibility. Moreover, any tendency for policymakers to disregard highly uncertain, low-probability, yet highly impactful events of this type is exacerbated by their "fat-tailed" distribution, which obscures their potential extremity. This article considers how plausibility-based scenario planning can increase preparedness for extreme events like a global pandemic, thereby reducing overconfidence in continued business-as-usual in their face, and emphasizing precaution in their wake. In so doing, the article contributes to what in this journal has recently been called "type B," "generic and fundamental" risk science, which is concerned with identifying better ways to present and communicate uncertainties. In focusing on plausibility-based scenario planning, the article highlights a method seldom previously discussed in relation to risk science, yet one that can contribute much to this type B component of it.