Hydroclimatic intensification in a warming world: is society ready for increasing precipitation whiplash?

Recent extreme precipitation events and subsequent severe floods in highly-populated urban areas have highlighted the considerable societal vulnerability to hydroclimatic extremes. From the widespread inundation of Houston, Texas due to a stalled tropical cyclone in 2017 to the localized but devastating debris flows near Santa Barbara, California resulting from a narrow atmospheric river-related downpour in 2018, it is clear that natural hazard risks associated with extreme precipitation events span a wide range of temporal and spatial scales. Meanwhile, scientific consensus regarding a global intensification of the hydrological cycle—characterized, in particular, by large increases in the frequency and intensity of the most severe precipitation events at the expense of more moderate ones—has been bolstered by a flurry of new research over the past several years. These new research findings, which are supported by both observational and modeling efforts, collectively suggest that human-engineered systems designed under assumptions of historical climate stationarity may cease to function as intended sooner than has been widely recognized. In this talk, I will discuss implications of projected regional hydroclimate changes for water and natural hazard risk management, as well as the importance of embracing spatiotemporal nuance in climate science and of developing societally-relevant metrics for quantifying changes in extreme event risk.