Flash droughts, short-term dry events characterized by rapid onset and intensification, are an increasing problem in a warming climate, especially in arid regions with limited water resources. This study focuses on the occurrence and characteristics of flash droughts in the Kashkadarya region of southern Uzbekistan using soil moisture (SM) data from the ERA5-Land reanalysis. The Flash Drought Intensity Index (FDII), which includes both drought intensification and severity components, was used to detect and assess flash droughts. The FDII was compared with the widely used Standardized Precipitation Evapotranspiration Index (SPEI6) to assess its robustness in capturing short-term drought dynamics. The results show that flash droughts of varying intensity and duration occurred repeatedly during the study period (1990-2019), especially in years such as 2000, 2001, 2008, and 2011. Comparative analysis between FDII and SPEI6 intensity confirmed the temporal consistency of extreme drought episodes. However, due to the specific SM patterns the FDII intensification component tends to capture peaks early in the growing season and may not reflect SM stress during the summer months. This limitation is due to the consistently low summer SM values without fluctuations, which reduces the sensitivity of the index. Overall, the study highlights the need to adapt the FDII threshold parameters to consider regional meteorological conditions. Accurate characterization of flash droughts is essential to support water management and climate adaptation strategies in droughtprone regions.
Rakhmatova et al. (2025) studied this question.