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The complexity of climate system dynamics calls for more elaborate drought evaluation and trend projection under different future climate scenarios. In this study, the meteorological drought stress over the Yellow River basin (YRB) of China for the next forty years (2021–2060) is comprehensively evaluated based on meteorological simulations of eight climate models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) with three representative concentration pathway scenarios (RCP2.6, RCP4.5 and RCP8.5). The standardized precipitation evapotranspiration index (SPEI) is used as a metric of drought magnitude at multiple temporal scales, while the multi‐threshold run analysis is conducted for the definition of drought events and derivation of drought characteristics (e.g., frequency, duration and severity). The Mann–Kendall test is adopted as a universal tool to analyse the trends in climate variables (precipitation and temperature), multi‐temporal SPEI drought indices and drought characteristics (duration and severity). Our preliminary conclusions include that partially increasing precipitation and generally rising temperature are likely to be seen in the YRB from 2021 to 2060. More importantly, a warmer YRB may undergo either a nearly regular atmospheric regime (e.g., comparable to the baseline period of 1961–2000) with RCP2.6 scenario or significantly drying processes with RCP4.5 and RCP8.5 scenarios. Meanwhile, the enhanced spatiotemporal variability/heterogeneity of meteorological forcing (e.g., precipitation and temperature) and drought characteristics (e.g., magnitude, frequency, duration and severity) would also increase future uncertainty of meteorological drought stress over the YRB, such as the encounter of drought with long duration and/or high severity and relevant increasing trends. Understanding the spatiotemporal influences of specific climate and emission scenarios on projected drought vulnerability might help improving our knowledge of climate‐human interactions and selecting rational development strategy (like the low emission scenario of RCP2.6 or so) for regional adaptation to future climate change. [ABSTRACT FROM AUTHOR]

Drought projection is of critical significance for designing long-term drought adaptation strategies to cope with changing climate. This study presents an application of multi-class models for characterizing future droughts in the Yellow River basin (YRB). Using meteorological observations and simulations of three CMIP5 climatic models as input into VIC hydrologic model, the standardized Palmer drought index-based joint drought index (SPDI-JDI) is calculated to investigate spatiotemporal patterns and possible changes of future drought in the YRB, through an approach of bivariate modeling and analysis. It is concluded that moderate drought will be alleviated with decreased duration and severity, but extreme drought risk is likely to increase for future climate scenarios (2021–2050) relative to baseline period (1961–2000). From the perspective of bivariate analyses, the concurrence probability of drought events with extreme duration and severity might rise in the future, while increasing variability and heterogeneity of duration, severity and bivariate joint/concurrent return period would also increase the stochastic occurrence of extreme drought over time and space. These findings can provide insights into projection of climate change impacts on drought trends for the next 30 years, and help to preparations for strict control of socio-economic water consumption as well as eco-environmental protection and restoration in the YRB. [ABSTRACT FROM AUTHOR]