• FD events were most frequent in humid and least in arid regions during 2001-2023. • Precipitation and temperature were identified as the dominant drivers of FD. • In China, humid-forests react to FD more quickly and intensely than arid-short vegetation. • The severity of FD is projected to increase markedly under high-emission scenarios. Flash droughts (FDs) develop rapidly and can strongly affect ecosystem functioning and water resources. However, their spatiotemporal variability in China and their effects on diverse ecosystems remain poorly characterized. In this study, the frequency of FD events during the growing season in China from 2001 to 2023 and their key driving interaction mechanisms were systematically analyzed. Using multisource remote-sensing indicators, including the leaf area index, potential evapotranspiration, and gross primary productivity, we quantitatively assessed response timing and impact intensity across different ecosystems. Furthermore, we projected future FD changes in China for 2000–2100 under different climate scenarios. The results reveal that FD frequency varies across different ecosystems in China, with the highest occurrence in humid regions (mean = 6.98 events) and the lowest in arid regions (6.13). Driver analysis indicates that drought risk increases notably under high temperatures and low precipitation. Furthermore, soil moisture dynamics exhibit a two-phase evolutionary pattern of “rapid depletion followed by differential recovery”, whereas ecosystem indicators demonstrate a “transient enhancement followed by persistent decline” response pattern. Compared to arid regions dominated by short vegetation, humid-forest ecosystems exhibit faster response times and greater intensity reactions to FD. The Coupled Model Intercomparison Project Phase 6 (CMIP6) multimodel ensemble projections indicate the most severe future conditions under the RCP5-8.5 scenario. These findings underscore how climate change threatens vegetation ecosystem stability and highlight the urgent need for effective mitigation policies and sustainable management strategies to protect terrestrial vegetation ecosystems.
Yuan et al. (Wed,) studied this question.