Unraveling the spatiotemporal dynamics and drivers of drought in Xinjiang: a prefecture-scale analysis using CHIRPS and SPEI

This study investigated the spatiotemporal dynamics and driving mechanisms of drought in Xinjiang Uygur Autonomous Region at the prefecture scale, using high-resolution CHIRPS precipitation data and the Standardized Precipitation Evapotranspiration Index (SPEI) from 2000 to 2024. Theil–Sen median trend analysis, Mann–Kendall significance test, and Run theory were applied to characterize precipitation patterns, drought evolution, and drought events. Results showed that Xinjiang exhibited widespread and significant precipitation decline, with higher precipitation in northern Xinjiang and the Tianshan Mountains, and extremely low precipitation in southern and eastern Xinjiang. The SPEI indicated a significant drying trend across Xinjiang, especially in the Tarim Basin and Turpan–Hami Basin. A total of 167 drought events were identified, with over 64% concentrated in southern and eastern Xinjiang, which showed higher frequency, longer duration, and stronger intensity. Drought intensification was mainly driven by the synergistic effect of reduced precipitation and enhanced potential evapotranspiration (PET) under climate warming. This study provides a refined prefecture-scale understanding of drought variability and offers a scientific basis for targeted drought mitigation, water resource management, and ecological adaptation in arid regions.