中国东部夏季风向北推进到达不同地区的强度和维持时间年与年及年代与年代之间的不同形成了中国东部夏季风区降水距平南北分布的年际和年代际变化。本项目研究的重点内容集中于下列三方面：(1) 建立有明确物理意义的区域夏季风强度指标，用于反映中国东部华南、华中（长江中下游流域）和华北的区域夏季降水量的年际和年代际变化；(2)建立中国东部华南、华中和华北三区域的千年夏季风强度指标序列，分析中国东部不同区域夏季风强度变化的规律；(3)从热力-动力学上认识和解释区域夏季风强度长期变化的原因，为区域夏季风年代际变化预测提供坚实的物理基础。

Inter-annual and inter-decadal variability of summer precipitation anomalies in various regions of easern China are associated with the inter-annual and inter-decadal variability of regional summer monsoon intensity and its persistent period. This study focuses on three study aspects:(1) constructing physical monsoon intensity indices to indicate the regional summer precipitaion variablity at interannual and interdecadal timescales in South China, Central China and North China;(2) constructing the regional summer monsoon intensity indices for the last millennium in South China, Central China and North China to identify their variations; and （3）understanding and explaining the causes of regional summer monsoon intensity variability to provide a solid physical basis of regional monsoon prediction at interdecadal timescale.