Future extreme precipitation may shift to colder seasons in northern mid- and high latitudes

Abstract

Despite high confidence in the intensification of the hydrological cycle due to global warming, the future spatiotemporal patterns of extreme precipitation remain uncertain. Here we explore how climate change influences the seasonal timing of extreme precipitation events, using daily output from the Coupled Model Intercomparison Project Phase 6. We show that at latitudes between about 45°N and 75°N in Eurasia and North America, where extreme precipitation typically peaks in summer, climate models project a substantial shift in the seasonal timing of extreme precipitation from summer into the colder seasons, spring and autumn, or even into winter, by the late 21st century. We show that this shift is associated with reduced moisture supply during strong updraft events in summer. These results point towards a need for improved representations of processes determining the change in the moisture availability and simulated vertical winds of the atmosphere as well as for adaptation to higher flood risk in colder seasons.