摘要
文中应用NCEP/NCAR 500 hPa逐日资料对影响华北盛夏旱涝的环流特征进行分析,给出了盛夏旱涝分别与“西高东低”和“东高西低”流型的对应关系。并进一步研究初夏与盛夏的环流演变特征,得知若在6月500 hPa华北出现异常增高过程时,则盛夏多出现“西高东低”流型,华北少雨;反之,6月华北出现异常低压过程时,盛夏多出现“东高西低”流型,华北多雨。6月华北高压区环流特征与盛夏的环流型相关系数达0.597,与华北中部盛夏降水相关系数为0.562,为初夏进行盛夏旱涝短期气候预测提供了依据。以此为根据建立了初夏对于天津盛夏降水短期气候预测的经验方法,在2002—2004年的业务应用中预报趋势都是正确的。
The relation between weather processes in early- and mid-summer is investigated using the NCAR/NCEP daily 500 hPa reanalysis data. It is shown that if there is a anomalously strong increase process of 500 hPa height over North China in June, then there will be more days when the circulation pattern of ＂west-high-east-low＂ dominates over North China in July and August, and the rainfall will be less; conversely, if there is a quite deep low process over North China in June, then there will be more days when the circulation pattern of ＂west-low- east-high＂ dominates in July and August, and the rainfall will be more. Correlation coefficients of the daily maximum positive height anomaly over the North China High region （40° - 45°N, 100° - 115°E） in June with the day number of the circulation pattern of ＂west-high-east-low＂ in July and August over North China, and the mid-summer rainfall in North China are 0. 597 and 0. 562 , respectively. Based on the above analysis results, a short-rang climate forecast empirical method for mid-summer rainfall in Tianjin was established, and its performance in the operational forecasts for mid-summer rainfall in Tianjin in 2002 -2004 is quite well.
出处
《气象学报》
CAS
CSCD
北大核心
2006年第3期385-391,共7页
Acta Meteorologica Sinica
基金
国家科技部社会公益类项目(2002DIB20067)
关键词
华北
盛夏旱涝
环流型
先兆过程
Mid-summer rainfall, North China, Circulation pattern, Early-stage weather process.
