华北夏季降水与哈得孙湾海冰的相关分析

利用195l一2000年全国160站逐月降水资料划分了华北夏季的旱涝年，并分析了该地区夏季降水的气候特征。在分析华北夏季降水与北极各海区海冰同期和滞后相关的基础上，发现哈得孙湾5—8月的海冰与同年华北夏季降水存在很好的负相关。同时发现哈得孙湾关键时段内的海冰与亚洲夏季风指数呈负相关，与8月西太平洋副热带高压的西伸脊点呈明显的正相关，而与8月西太平洋副高的强度呈明显的负相关。此外还发现哈得孙湾海冰多、少年，东亚西风急流有显著差异。结果表明，哈得孙湾关键时段内海冰面积偏大(小)，同年亚洲夏季风偏弱(强)，8月西太平洋副高的位置偏东(西)，强度偏弱(强)，东亚西风急流减弱(加强)。

Relationship between Summer Rainfall in North China and Sea-Ice in Hudson Bay

By use of monthly summer rainfall data of 160 stations from 1951 to 2000 in China,the dry wet years have been divided,and the climatic characteristics of summer rainfall in this area have also been analyzed.The analysis of contemporary correlation and lag correlation between summer rainfall in North China and sea-ice in different sea areas of Arctic show that the correlation coefficients are remarkably negative between summer rainfall of North China and sea-ice of Hudson Bay from May to August in the same year.In addtion,sea-ice of Hudson Bay in key time interval has negative relationship with index of Asian summer monsoon,postive relationship with the western extension of subtropical high ridge in western Pacific in August,and negative relationship with the intensity of the western Pacific subtropical high in August.Westerly jet of Eastern Asia is very different in heavy/light sea-ice years.Results show that when sea-ice area of Hudson Bay is larger(smaller),Asian summer monsoon in the same year is weaker(stronger),location of the west Pacific subtropical high is eastern(western)of its mean location,intensity of subtropical is weaker(stronger),westerly jet of Eastern Asia is weaker(stronger).