摘要
运用NCEP/NCAR再分析资料、英国气象局的海温资料和国家气候中心整编的160站月降水量资料,对江淮夏季降水及其前期冬季环流和海温场进行分析,并利用NCAR CCM3模式进行海温的敏感性试验。结果表明:前期环流在亚洲中高纬地区有明显的异常,这种环流异常与北太平洋西北部的海温异常有关,西北太平洋海温异常偏高(低)是江淮夏季降水偏多(少)的重要原因之一,即当前期西北太平洋海温异常偏高时,后期夏季从乌拉尔山到鄂霍次克海附近为高度正距平,亚洲中纬度为弱的负距平,这时亚洲中高纬度多阻塞高压活动,中纬度多低槽活动,有利于冷暖空气在江淮地区交汇,江淮流域降水偏多;反之,江淮流域降水偏少。
Relationship between summer rainfall in the Changjiang-Huaihe valley and previous winter（DJF） circulation,SSTA is investigated,in terms of the NCEP/NCAR reanalysis data,the SST（sea surface temperature） data reorganized by British Meteorological Department,and the 160 station monthly precipitation data from NCC（China National Center of Climate）.Then sensitive experiments to SSTA are conducted with the NCAR CCM3 model.Results show that the summer rainfall is closely related to the circulation anomalies at high latitudes over Asian,which are related with the winter SSTA of Northwest Pacific.As the SSTA of Northwest Pacific in winter is higher than normal,the positive height anomaly will occur over the area from Ural Mountains to the Okhotsk Sea,the weakly negative one over Asian mid latitudes in next summer.Therefore,more than normal blocking highs over Asian at high latitudes and troughs at lower-mid latitudes will be helpful for cold air and warm air to meet over the Changjiang-Huaihe River valley,producing positive rainfall anomalies;and vice versa.
出处
《南京气象学院学报》
CSCD
北大核心
2007年第4期472-478,共7页
Journal of Nanjing Institute of Meteorology
基金
国家自然基金科学基金重点资助项目(40331010)
国家自然科学基金资助项目(40505014)
江苏省气象灾害重点实验室资助项目(KLME050304)
关键词
江淮地区夏季降水
成因分析
数值试验
summer rainfall in the Changjiang-Huaihe valley
diagnosis
numerical experiment
