Meteorological flash droughts risk projections based on CMIP6 climate change scenarios

Abstract

Meteorological flash droughts (MFDs) are sub-seasonal-to-seasonal drought phenomena characterized by rapid onset/intensification. This study assesses the changes in trends and hotspot regions of MFDs for the present and five future CMIP6 SSP forcing scenarios (SSP-FS) at global-, continental- and regional-scales. Analysis with 12 GCMs indicates that globally, frequency, duration and severity of MFDs are projected to increase ~20–50%, 20–58%, and 26–62%, respectively, with the highest occurrence probability during the summer season. The MFD hotspot regions appeared prominent in arid and semi-arid zones. MFD exposure risk is projected to exceed ~1.5 folds in most continents, with the highest risk in the Indian sub-continent. Furthermore, in Europe and South America, which are currently less impacted by MFDs, a considerable increase in hotspot regions (~122–127%) is projected under the warmest SSP-FS. The LULC-classes and elevation range most vulnerable to MFDs, and regional potential hydrometeorological drivers that trigger the development of MFDs are identified.