Increasing coupling of hot‒dry winds and drought across China: Observational evidence and future projection

Hot‒dry winds (HDW) and droughts are two prevailing climate hazards posing increasing threats to human societies and natural ecosystems. Insights into compound HDW and drought events (CHDWDs) fill gaps in understanding their synergistic pattern and enable more disaster prevention strategies to mitigate consequent damage. By using meteorological observations and multi-model simulations from the Coupled Model Intercomparison Project Phase 6 (CMIP6), we analyzed the historical spatiotemporal patterns of HDWs, droughts, and CHDWDs across China, projected their future changes under different SSP (Shared Socioeconomic Pathway) scenarios, and quantified contributions of individual events to CHDWD frequency and intensity. Findings have revealed intensified HDW severity (−0.05 per decade, p < 0.05) and drought conditions (−0.07 per decade, p < 0.01) during 1980–2022, with a strong positive correlation (r = 0.79, p < 0.01) between them. The likelihood of CHDWDs has significantly increased across China (0.093 per decade, p < 0.01), with drylands being more susceptible. Droughts exert a larger influence on CHDWDs in arid regions (77%–91% to frequency and 55%–76% to intensity), while HDWs are more influential in humid areas (41%–46% to frequency and 57%–64% to intensity). Future simulations project increased frequency and strengthened intensity of CHDWDs from 2075 to 2100 under SSP5-8.5 and SSP3-7.0. Under SSP3-7.0 and SSP1-2.6, droughts dominate CHDWD frequency (68%–87%) in most regions, while under SSP5-8.5, HDWs contribute more (54%) than droughts in humid regions. To CHDWD intensity, HDWs contribute more (53%–71%) than droughts in humid regions, and droughts contribute more (54%–83%) than HDWs in non-humid regions. These results are valuable for improving agricultural risk management and guiding the development of targeted adaptation strategies.