中文摘要：

针对黄河流域近年来干旱频繁发生和水资源匮乏状况,基于1961-2010年黄河流域146个气象站的逐月降水和干流6个水文站的逐月径流资料,采用标准降水指数（SPI）、标准流量指数（SDI）及其相关评估指标,运用趋势、时滞互相关等气候学分析方法,分析了近50年黄河流域气象和水文干旱时空变化特征.结果表明：全流域年气象干旱表现出加剧趋势,且中游干旱化较突出.中游春旱、全流域秋旱和上、下游夏旱均呈加剧趋势,而全流域冬旱出现减轻态势,以上游较突出.沿干流从上游至下游水文干旱呈加重趋势,且自1990s后期开始水文干旱的发生更加频繁,干旱等级也越来越高.流域水文干旱主要与流域干旱、半干旱气候区的气象干旱有1～5个月的滞时.

英文摘要：

In this study, 146 weather stations and 6 hydrological stations were selected for analyzing the spatial-temporal charac- teristics of the meteorological and hydrological droughts by Standardized Precipitation Index（SPI）, Standardized Discharge Index （SDI） and associated assessment indicators with the trend, time lag cross-correlation analysis climate methods across the Yellow River Basin（YRB） during 1961--2010, which facing frequent occurrence of droughts and serious water shortage. The results show that, annual meteorological drought in the YRB have shown increasing trend, especially in the midstream. Spring drought in midstream,autumn drought in the whole basin, summer drought in upstream and downstream are shown increasing trend. However,winter drought in the whole basin appears to be mitigation trend, especially in the upper reaches. Hydrological drought indicates increasing trend from upstream to downstream, and more frequent hydrological drought has occurred, and drought severity has being also growing since the late 1990s. Furthermore, it is obvious that hydrological and meteorological drought with the lag time between 1-5 months at the arid and semi-arid climatic zones in the YRB.