基于CHIRPS与SPEI数据集的云南省干旱监测研究OA

Yunnan Province is located in the marginal zone of the monsoon region,where droughts have been occurring frequent-ly in recent years and have shown pronounced spatiotemporal heterogeneity under the combined influences of climate change and complex topography.To accurately characterize regional drought dynamics and enhance drought disaster preparedness,we conduc-ted a quantitative drought monitoring analysis based on high-resolution spatiotemporal data.Using CHIRPS satellite precipitation data and the Standardized Precipitation Evapotranspiration Index(SPEI)for the period2000～2022,we applied the Theil-Sen median trend estimator and the Mann-Kendall test to systematically examine trends in precipitation,drought frequency,drought duration,and spatial distribution characteristics at the prefecture-level city scale across Yunnan Province.The results indicated that southeastern,central,and northwestern Yunnan experienced relatively high drought frequency during 2000～2022,with a sta-tistically significant intensifying trend,the cumulative number of drought events exceeding 15 in these regions.In southeastern Yunnan,the longest drought duration occurred in 2019,lasting up to 8 months,with a minimum SPEI value of-1.8,indicating substantial drought severity.A significant association was identified between decreasing precipitation and increasing drought fre-quency,with particularly pronounced impacts in Kunming,Yuxi,Honghe Prefecture and other regions.These findings reveal the regional disparities and spatio-temporal patterns of drought evolution in Yunnan Province and provide both a data foundation and theoretical support for the development of differentiated drought emergency response strategies at the prefectural and municipal levels.