Abstract
Addressing impacts of flash droughts (FDs) on the water-food nexus
requires a understanding of FD mechanisms and drivers at the watershed
level. Examining climatic drivers, dry and wet spell lengths from 1980
to 2019, we analyzed FD spatial and temporal characteristics,
emphasizing areal extent, onset time, and duration. Our findings reveal
substantial variations in FDs among different watersheds. Notably,
watersheds in the Southern Hemisphere are witnessing expanding,
faster-developing, and longer-lasting FDs, aligning with climate
variations in precipitation and temperature. Additionally, at the
watershed scale, the onset and duration of FDs are influenced by
climatic drivers but remain unaffected by the duration of wet and dry
periods. FD extents, however, correlate with both climatic conditions
and wet and dry periods, underscoring watershed connectivity.
Ultimately, our results underscore the necessity for research to
comprehend the interplay between FDs and watershed characteristics and
how it manifests in overall water resource management.