宁夏地表湿润状况演变规律研究  

The research on the change of surface humid index in Ningxia

作　　者：郑广芬[1,2] 陈晓光[1] 纳丽[1] 张智 许建秋[1] 

机构地区：[1]宁夏气象防灾减灾重点实验室,银川750002 [2]宁夏气象台,银川750002

出　　处：《气象科学》2008年第5期533-538,共6页Journal of the Meteorological Sciences

基　　金：国家科技部项目“宁夏气候对全球气候变化的响应及其机制(2004DIB3J121)”

摘　　要：利用1961—2004a宁夏23站月降水和平均气温资料,通过计算地表湿润指数,分析了宁夏区域平均及不同区域地表湿润指数的年代际变化特征及季节性差异。最后,给出了地表湿润指数年及各季节变化趋势的地理分布。结果表明:近40 a来宁夏年地表湿润指数总趋势是下降的,即地表在变干;地表湿润指数的变化具有明显的阶段性特征,即1970s末期以前的冷湿期,1970s末至1980s中期的冷干期,1980s中期以来的暖干期;宁夏的干化趋势主要发生在秋季;宁夏年、秋季地表显著变干的中心区域主要集中在中部干旱带及南部山区的北部;冬季南部山区存在显著变湿趋势,春、夏季各地均无显著干、湿变化趋势。Based on the 23 observational station＇s data of monthly precipitation and mean monthly temperature over Ningxia from 1961 to 2004, by use of the surface humid index computed from the data, decadal variation and the seasonal differences of the surface humid index over Ningxia have been analyzed. The geographical distributions and trends of surface humid index have been given in this area. The results indicated that the total trend of the surface humid index of Ningxia has dropped in past more than 40 years, namely the earth＇s surface is becoming dry. The change of the surface humid index has obvious phase char- acteristics. Cold and wet climate was main characteristic of Ningxia from the sixties to latter stage of the seventies. The climatic characteristic was cold and dry from 1978 to 1988. And the climate has been warm and dry since the 1990s. The drying trend of Ningxia generally occurred in autumn. The centre area where the earth＇s surface becomes dry notably was in the central arid strip part and the north part of loess hills area of south in Ningxia. The winter has an tendency of wetting in loess hills area of south in Ningxia. But there is no notably wet or dry tendency in all parts of Ningxia in spring and summer.

关 键 词：宁夏 地表湿润指数 气候变化 

分 类 号：P412[天文地球—大气科学及气象学]