近期有研究表明，1980s以来北大西洋海温异常对东亚夏季风及其关键环流系统存在显著影响，前者可能是东亚夏季季节气候预测的重要可预报性来源之一，但目前对其影响机理仍缺乏清晰认识。为此，本项目拟采用诊断分析与数值模拟相结合的手段，系统考察年际时间尺度上北大西洋海温异常与东亚夏季风及夏季降水之间的联系；分析北大西洋海温异常信号的东传路径与关键物理过程，揭示海温异常通过信号东传进而影响东亚夏季风和夏季降水年际变率的物理机制；探讨背景环流对北大西洋海温异常信号东传路径的可能影响，揭示前者对北大西洋与东亚夏季气候年际关系的调制作用及其机理；分析业务气候模式对北大西洋海温异常与东亚夏季气候之间年际关系的模拟性能，指出模式模拟中存在的主要误差来源及其成因。预期结果可为东亚汛期季节气候预测和模式改进提供科学参考。

Recent studies showed that sea surface temperature (SST) anomalies over the North Atlantic could exert significant impact on the East Asian summer monsoon (EASM) and the monsoon-related atmospheric circulations on the interannual time scale, and the former may be a potential source of the seasonal predictability of the East Asian summer climate. However, mechanism responsible for the linkage of the East Asian summer climate to the North Atlantic SST anomalies remains unclear. Therefore, this study attempts to examine relationship of the North Atlantic SST anomalies with the EASM and East Asian summer precipitation on the interannual time scale. More importantly, we will investigate mechanism responsible for the impact of the North Atlantic SST anomalies on the East Asian summer climate by focusing on the eastward propagation of North Atlantic SST signals. Additionally, we will investigate roles of mean state on modulating relationship between the North Atlantic SST anomalies and interannual variability of the East Asian summer climate. Finally, model ability in simulating relationship between the North Atlantic SST anomalies and East Asian summer climate will be evaluated, and model errors in simulating such a relationship and the possible causes will be explored. It will aim to provide a scientific basis for the seasonal forecast of the East Asian summer climate and model development.