Increasing Risk of Wild Swings between Droughts and Floods over Global Land Areas

Abstract Climate variability is nothing new. Of rising concern is the consecutive occurrence of reversed weather patterns — droughts followed by severe floods, which tip a precarious balance with lasting impacts on human and natural systems. Here we examined changes in the likelihood and spatial distribution of dry-to-wet precipitation events over global land surface using climate model projections. We find anthropogenic climate change is likely to stress more widespread regions with rapid see-saw changes from dry to wet spells by the end of the 21st Century, increasing the threat to water security. Additionally, Eastern North America, South and East Asia, and Eastern Africa are emerging future hotspots of extreme drought-deluge swings by yielding marked enhancements in the events’ occurrence probability and spatial coverage. This study can provide useful information for policy makers to develop integrated approach to drought and flood management, while broadening the scope of research on compound climate extremes.