嘉兴夏季降水与副高的年际年代际变化关系分析  

Interannual and Interdecadal Variation of Relation between Summer Precipitation in Jiaxing and Subtropical High

作　　者：陈优平[1] 余志豪[2] 

机构地区：[1]浙江省嘉兴市气象局,嘉兴314050 [2]南京大学大气科学系,南京210093

出　　处：《气象科技》2007年第3期359-362,共4页Meteorological Science and Technology

基　　金：国家自然科学基金(4023-3028)项目赞助

摘　　要：为了定量描述副高变化及其与嘉兴夏季降水的关系，在500hPa高度场上选择一个特定的关键区定义了一个副高指数，分析发现该指数既存在大于45年周期、准9～16年的年代际变化周期，也存在4年和准2年的年际变化，与降水间存在很好的相关关系，可以作为预测降水的一个重要因子。嘉兴夏季降水与西北太平洋副热带高压在1980年前后发生了一次同期的年代际尺度跃变。1980年以前，副高强度明显偏弱，主体偏东，嘉兴夏季降水偏少；而1980年以后则反之。In order to describe quantitatively the relation between subtropical high variation and summer precipitation in Jixing, a subtropical-high index is defined by selecting a specified key area on 500 hPa. The analysis of the index indicates that there existed very good relation between subtropical-high index and summer precipitation with interdecadal variation periods of more than 45 years and about 9 to 16 years, as well 4 years and quasi-2 years. The index can be used in operational precipitation forecasting. There occurred a synchronous interdecadal jump in summer precipitation in Jiaxing and Northwest Pacific Ocean tropical high around 1980. Before 1980, the tropical high intensity was weaker and farther eastern less than normal; and after 1980, vice versa. than normal, while the precipitation in Jiaxing was

关 键 词：降水 大气环流 副高 年际变化 年代际变化 

分 类 号：P467[天文地球—大气科学及气象学]