Multi‐Indicator Assessment to Assess the Increasing Impacts of Compound Dry and Hot Events on Global Wheat Yield

Abstract In a warming climate, the co‐occurrence of drought and heat events increasingly threatens the global wheat yield and food security. However, changes in compound dry and hot events (CDHEs) during the global wheat growing season and their impacts on yield remain largely unknown. Using daily ERA5 reanalysis data, multiple drought indicators including the standardized precipitation index, standardized precipitation evapotranspiration index, standardized soil moisture index (SSI), and heat indicators the standardized temperature index and standardized soil temperature index (SSTI), are compared to assess the evolution of CDHEs and their impacts on wheat yield in major wheat‐producing regions (1981–2020). The results indicate significant increases in the frequency, duration, and intensity of global CDHEs, with the most pronounced increases experienced in arid and semiarid regions (Eastern Europe, Central Asia, and Turkey). SSI–SSTI was most sensitive to frequency changes, SPEI–SSTI best captured intensity and duration, and SPI–STI provided conservative estimates. These trends reflect regional hydrothermal conditions, land–atmosphere interactions, and agricultural management. When CDHEs account for more than 10% of the growing season, over 70% of wheat areas experienced negative yield anomalies with an average anomaly of −6.3%; Canada, Australia, and Central Asia were severely impacted, whereas highly irrigated regions (e.g., China and India) were less impacted. Indicator combinations incorporating evapotranspiration and soil moisture (SPEI–SSTI, SSI–SSTI) were most strongly correlated with yield anomalies, highlighting their effectiveness for compound stress detection. This study emphasizes the importance of multi‐indicator assessments and regional adaptations for developing climate‐resilient agricultural strategies.