基于多尺度气候因子的喀斯特地区气象干旱驱动分析OA

To unravel the multi-scale driving mechanisms of meteorological droughts in karst regions,we calculated the SPEI at 1-,3-,6-,and 12-month time scales using data from 31 meteorological stations in Guizhou Province from 2000 to 2023.Correlation analysis,wavelet analysis,and geographical detector techniques were used to analyze the spatiotemporal evolution of meteorological drought and its formation mechanisms under the combined influence of global atmospheric circulation and local environmental fac-tors.The results indicate that drought intensity showed a slight but statistically insignificant weakening trend overall at temporal scale.Spatially,areas with high drought frequency were concentrated in the southwestern and eastern regions,where karst development is most pronounced.The driving mechanisms exhibited significant scale dependence.Specifically,the PNA factor of the atmospheric circulation pattern had the strongest direct influence on monthly-scale drought,and the influence are often ahead of time.The MEI.V2 controlled the longest-period oscillation of seasonal-scale droughts but with a 1.5-month lag,suggesting a potential modulating role of karst water storage.Droughts at longer scales were influ-enced by the combined effect of low-frequency circulations such as NAO and PDO.Among local factors,precipitation and wind speed were the main driving sources,and the interaction between the two factors showed a nonlinear enhancement effect,with the coupling of NDVI and meteorological factors being par-ticularly crucial.The scale-dependent driving framework of"large-scale circulation triggering and multi-factor nonlinear synergy"constructed in this study can provide technical support for precise regional drought prevention and control.