柘溪水库流域降水特征及旱涝成因分析  

Analysis of Precipitation Characteristics and Causes of Drought&Flood in Zhexi Reservoir Basin

作　　者：郭海峰 刘瑞琪 刘祥 廖春花 GUO Haifeng;LIU Ruiqi;LIU Xiang;LIAO Chunhua(Hunan Meteorological Service Center,Changsha 410118,China;Chongqing Meteorological Service Center,Chongqing 401147,China;Hunan Province Key Laboratory of Preventing-diminishing Meteorological Disasters,Changsha 410118,China)

机构地区：[1]湖南省气象服务中心,湖南长沙410118 [2]重庆市气象服务中心,重庆401147 [3]气象防灾减灾湖南省重点实验室,湖南长沙410118

出　　处：《水文》2022年第2期96-101,共6页Journal of China Hydrology

摘　　要：利用CIMISS平台提供的降水资料以及ERA-Interim再分析资料,通过趋势分析、滑动t检验、小波分析、EOF分解等方法,对1971—2016年柘溪流域降水时空变化特征以及旱涝年降水差异的成因进行了分析。结果表明:柘溪水库流域月平均降水量以4、5、6月为最多;年平均降水量呈现逐渐增加的趋势,其中夏季降水增加较快,而春季降水则呈现出下降的趋势;20世纪90年代初有一个降水增多的突变;柘溪水库流域降水空间分布不均,西北多、东南少,年平均大雨日数也呈现出同样的分布形态。在涝年,西太平洋副高偏西、偏北,东亚大槽偏强,我国南方地区存在异常的西南气流,低纬地区东风系统异常活跃,水汽输送较强。在旱年,情况与之相反。Based on precipitation data from China integrated meteorological information service system and ERA-Interim reanalysis data,this paper analyzed the precipitation characteristics and causes of drought&flood in Zhexi reservoir basin during 1971-2016 by using trend analysis,moving t-test,wavelet analysis and empirical orthogonal function.The results show that the average monthly precipitation of the basin reached the maximum point during April-June.The average annual precipitation showed an upward trend,with a rapid increase in summer and a downward trend in spring.There was an abrupt increase of precipitation in the early 1990s.The spatial distribution of precipitation was uneven with the northwestern part witnessing more precipitation than the northwestern part.The same distribution pattern was observed in the annual average number of days of heavy rain.In flood years,the position of western Pacific subtropical high tended to be more westward and northward,and the East Asia major trough was stronger.There was an abnormal southwesterly airflow in southern China and an unusually strong easterly wind burst in the low latitude area.Meanwhile,the water vapor transport was stronger.In drought years,circulation anomalies in the opposite sense occurred.

关 键 词：流域 降水特征 小波分析 滑动t检验 

分 类 号：P461[天文地球—大气科学及气象学]