南海表层海温对两类El Nino Modoki（I 和II）的响应及反馈机制

我国气候变化显著受到南海的影响，南海的年际变化与ENSO有紧密的联系。随着El Ni?o Modoki 的发现，在科学和社会意义上对南海与热带太平洋间相互作用的研究提出了新的要求。申请人前期工作首次揭示出两种El Ni?o Modoki（I和II）：其暖海温分布型显著不同，且对我国南方降水、台风活动以及印度洋偶极子都具有不同的影响。本项目将以观测事实为基础，通过统计分析、热收支方程以及数值模拟，拓展和深入研究南海海表温度与热带太平洋间的相互联系。主要回答两个关键科学问题：（1）两类El Ni?o Modoki（I和II）造成南海暖、冷海表温度异常的物理机制；（2）南海海表温度异常对两类El Ni?o Modoki（I和II）在衰退期的调制作用。这些工作，能加深对南海上层海洋环流规律的认识，增加对南海海－气相互作用及其在区域气候变化中作用的理解，为南海海洋大气的短期气候预测提供理论依据。

The changes of the South China Sea (SCS) impact greatly on the climate in China, and are associated closely with El Ni?o-Southern Oscillation on interannual timescales. In recent years, a new type of El Ni?o, named El Ni?o Modoki, is discovered. Therefore, the research on the interactions between the SCS and the tropical Pacific is further studied to meet the scientific and social requirements. Our previous studies classified El Ni?o Modoki into two groups: El Ni?o Modoki I and II with different origins and patterns of warm sea surface temperature (SST) anomalies, which show distinct impacts on rainfall in southern China, typhoon landfall activity and even the Indian Ocean dipole. Based on the observations, the proposed research aims at expanding and deepening our understandings of the relationships between the SCS SST and the tropical Pacific via statistical analysis, budget analysis of the thermodynamics equation in the upper mixed layer, and the model simulations. The proposed study will answer the two key questions: (1) the physical mechanisms of how two groups of El Ni?o Modoki (I and II) induce warm and cold SST anomalies in the SCS; (2) the roles of the SCS SST of how modulate two groups of El Ni?o Modoki (I and II) during their decaying phases. These results are helpful to feature the oceanic circulations at upper level in the SCS, and can improve our understandings of the air-sea interaction in the SCS and its important roles in the regional climate change. In addition, these results can supply theoretical basis to short-term climate prediction, which is beneficial to the scientific and social community in general.