摘要
统计分析了1951—2002年52 a长江中下游夏季降水的年际和年代际变化特征。结果显示:长江中下游夏季降水在20世纪60、70年代处于少雨期,80年代旱涝相间,90年代处于多雨期,而且年际异常和年代际异常的配置决定了旱涝的强弱。在此基础上,分析了长江中下游夏季旱涝年的前期潜热和感热通量在年际和年代际尺度上的异常合成场,以及夏季旱涝年同期大气环流场及风场的异常合成场。结果表明:中北太平洋西部(T区)和日本以东洋面(R区)当年春季热通量的异常分布形势是长江中下游夏季旱涝的一个前期讯号。
The characters of inter-annual and inter-decadal variations of summer precipitation over the mid- and low-reaches of Yangtze River have been statistically analyzed from 1951 to 2002. Results indicate that the 1960＇s and 1970＇s are dry-spells and the 1990＇s a wet-spell,and the 1980＇s is a transition period of drought alternating with flood. Drought and flood are determined by the polarities of the interannual and inter-decadal changes. On this basis, simultaneous temporal and time-lagged realtions of the composite latent heat and sensible heat flux anomalies with the atmospheric circulation anomalies on the inter-annual and inter-decadal scales are analyzed. Results show that the heat flux anomalous mode in the T and R areas in the preceding spring is a presage for the summer rain anomaly in the mid- and lowreaches of Yangtze River.
出处
《南京气象学院学报》
CSCD
北大核心
2007年第1期26-33,共8页
Journal of Nanjing Institute of Meteorology
基金
国家重点基础研究发展计划项目(2004CB418303)
国家自然科学基金重点资助项目(40331010)
江苏省气象灾害重点实验室资助项目(KLME060301)
关键词
年际和年代际变化
旱涝
热通量异常
讯号
inter-annual and inter-decadal variations
dry and wet spells
heat flux anomaly
presage
