Investigating the vulnerability and resilience capacity of different land cover types to flash drought: A case study in the Mississippi River Basin.

Abstract

Flash droughts are rapidly intensifying drought events that can have severe impacts on both natural and human systems. This study assesses the vulnerability and resilience of different land use and land cover (LULC) types to flash droughts in the Mississippi River Basin (MRB) from 2000 to 2022. Using the Standardized Antecedent Precipitation Evapotranspiration Index (SAPEI) to identify flash drought events and Gross Primary Productivity (GPP) data to define recovery periods, 315 unique flash drought events were identified, with the top ten most severe events analyzed in detail. The identification of flash drought events was done using a spatiotemporal method that combines spatial tracking of contiguous drought areas with rapid intensification criteria. The study found significant variability in recovery times across the MRB, with durations ranging from 8 to 120 days. Regions that experienced the most severe drought conditions, particularly during the 2006, 2012, and 2022 flash drought events, exhibited the longest recovery periods, indicating prolonged ecological stress. Forested areas demonstrated higher resilience, with shorter recovery times, while agricultural lands, particularly those reliant on rain-fed crops, showed the longest recovery periods, highlighting their vulnerability to rapid moisture loss. The Missouri River Basin and Upper MRB, characterized by lower annual precipitation and higher potential evapotranspiration, often exhibited the longest recovery durations due to their extensive agricultural activities. These findings underscore the importance of targeted drought management strategies, including the implementation of more robust water management practices and the adoption of drought-resistant crops, to mitigate the impacts of flash droughts and enhance the resilience of vulnerable regions in the MRB.