南海是我国夏季风的主要水汽源与水汽通道，也是印太海域主要的大气对流中心，研究南海上层热含量变化对于理解区域海气相互作用，以及边缘海与开阔大洋之间的热量再分配过程具有重要的意义。由于缺乏相对完整的长期次表层温度观测资料，南海上层热含量在年代际尺度上的变率特征及机制尚且不清楚。本项目拟基于全新收集的南海物理海洋数据库和多套再分析资料，采用统计方法、理论分析方法和数值模式等工具，揭示南海上层热含量年代际变化的时空分布特征和控制因子，最终阐明与年代际太平洋涛动有关的南海局地大气环流变化和太平洋风场变化等两种不同强迫方式在南海上层热含量年代际变化中的作用。本项目的实施能够进一步加深理解南海区域海洋对全球气候变化的响应，又有助于提高区域气候预测的能力，并对我国南海海域经济和安全的发展提供保障支撑。

The South China Sea (SCS) is the main source and channel of water vapor during monsoon season, and the SCS is also the main convective center over the Indo-Pacific region. It is of great significance to study the variations of upper ocean heat content (OHC) in the SCS for understanding the regional air-sea interaction and the process of heat redistribution between the marginal sea and open ocean. Due to lack of relative complete long-term observational temperature data in the sub-surface, the decadal variations of upper OHC in the SCS still remain unclear. Based on collecting the newest SCS Physical Oceanographic Dataset and reanalyzed datasets, by using statistical methods, theoretical analysis methods and numerical models, our project aims to reveal the spatial-temporal characteristics and controlling factors of the decadal variations of SCS OHC. The role of the local atmospheric circulation forcing over the SCS and the Pacific wind forcing related to the Inter-decadal Pacific Oscillation in the decadal variations of SCS OHC will be illuminated finally. The findings from this project can deepen our understandings of the response of SCS to the global climate change, and also help to improve the regional climate prediction, at last provide support for the economic and security development of the SCS region.