Spatiotemporal Droughts Propagation and Direct Driving Variables Under Climate Change Projections: A Case Study of Tunisia

ABSTRACT Projecting drought occurrence and spatiotemporal propagation under climate change remains challenging due to complex interactions among climatic, meteorological, and environmental factors. This study assesses projected drought dynamics in Tunisia under RCP4.5 and RCP8.5 scenarios through an integrated and comparative analysis of three complementary drought indices: the Standard Precipitation Index (SPI), Standardised Precipitation Evapotranspiration Index (SPEI), and Standardised Palmer Drought Index (SPDI), at seasonal (3‐month) and annual (12‐month) scales. By jointly examining these indices, the approach captures distinct drought‐generating mechanisms and their responses to future climate forcing. Linear correlation and mutual information analyses were applied to evaluate relationships between droughts and potential climatic drivers, capturing both linear and nonlinear dependencies. Results indicate significant warming and a less consistent drying trend during 2040–2100 compared to 1975–2005. Severe droughts are projected to increase in frequency, duration, and severity, propagating from southern to northern Tunisia. Drying soil moisture conditions in the north highlight future risks for agriculture and water management. Drought drivers vary by index, scale, and location, identifying southern Tunisia as a hotspot under future climate change.