【摘要】 基于山西省境内较为均匀分布的70个地面气象观测站57 a（1960-2016年）的逐日降水量、气温、日照时数、相对湿度、风速、水汽压等气象资料,选用国家标准中相对湿润度指数（M）,在其基础上构建了改进的相对湿润度指数(M_10i)作为干旱指标,以年、季为时间尺度,研究山西省干旱频率和强度的空间分布特征,并分析干旱频率和强度的年际变化规律。结果表明:改进的相对湿润度指数可很好地表征出典型干旱年;从57 a的资料来看,山西干旱程度总体呈现加重的趋势;对比各年代干旱程度,以20世纪60年代干旱最轻,80年代和90年代干旱最为严重,90年代之后又呈现逐年代减轻的趋势;山西省干旱强度呈北高南低的分布,北部大部、太原中部干旱强度最强;冬季、春季干旱强度明显高于夏季和秋季;山西省历年特旱的频率明显高于其他等级的干旱,重旱频率略高于轻旱和中旱的频率;大多数年份,山西省冬季总干旱频率最高,春季次高,秋季较低,夏季最低。更多还原

【Abstract】 Based on 57 years（ from 1960 to 2016） data of daily precipitation,temperature,sunshine hours,relative humidity,wind speed and vapor pressure from 70 meteorological stations in Shanxi,we calculated modified relative moisture index（ M10 i） using the relative moisture index（ M）. The spatial distribution of drought frequency and intensity in Shanxi was analyzed at annual and seasonal scales. The results showed that drought years were well expressed by M_10i. In the study period,annual drought intensity tended to be more serious. Drought was light in the 1960 s,and became serious in the 1980 s and 1990 s,then continuously decreased. Spatially,drought intensities were higher in the north and lower in the south,with the most severe drought in the north and the middle part of Taiyuan. Drought was more serious in winter and spring than in summer and autumn. Specially,heavily severe drought occurred with the highest frequency,followed by severe drought,light drought,and moderate drought. Drought happened most frequently in winter,followed by spring,autumn and summer in Shanxi.更多还原