太平洋-印度洋贯穿流南海分支与印尼贯穿流的相互作用及气候效应

The Pacific-Indian Throughflow is most important pathway which transports huge the Pacific Ocean water and heat into Indian Ocean. Previous studies have shown that the Pacific-Indian Throughflow has multiple branches when it cross the complex Indonesia seas, which includes Indonesia Throughflow（ITF） through the Makassar Strait, and the South China Sea Branch（SCSB） through the South China Sea and Karimata Strait. As we know, The ITF plays important role on the water mass exchange between the Pacifc Ocean and Indian Ocean,and it is key part of the global thermohaline conveyor. Recently the scientists gradually pay attention on SCSB. Although the depth of Karimata Strait is shallow and transportation of SCSB is less than that of ITF, but it has an important effect on the thermodynamic properties of seawater in the South China Sea and Indonesian seas. Before meeting in Indonesian Seas, the water carrying by ITF and SCSB pass by different seas,which leads to the important difference of water properties between them.So when they meet in Indonesia seas, they must have dramatically interact by the mixing and buoyancy forcing. Then it will affect the water thermodanamic property of Indonesian seas and transport/exchange between two oceans. Based on the observation data and satelite data, this project will study the interaction of two currents by the means of numerical simulation and objective analysis,and to explore interaction mechanism, and to reveal the interaction's effects on the climate in the South China Sea and Indonesian seas.

太平洋-印度洋贯穿流是两大洋水体、热盐交换的重要通道。已有的研究表明其穿越复杂的印尼诸海峡时存在多个分支，包括穿越望加锡海峡的印尼贯穿流和穿越南海和卡里马塔海峡的南海分支。印尼贯穿流早已被公认是两大洋水体交换的主要途径，也是全球热盐输送带的关键环节。贯穿流南海分支近年来也逐渐被科学家们所重视，虽然其水深和流量小于印尼贯穿流，但对于南海和印尼海水团的热力性质有着重要影响。由于两支海流的路径不同，其携带水体的性质存在显著差异，因此两支海流在印尼爪哇海和弗洛里斯海相会时，必然会通过混合、浮力强迫等过程产生相互作用，进而影响到印尼海的水体热力性质以及两大洋的热盐交换。本项目将依据近年来已经获取的大量温盐和海流观测资料，结合卫星遥感资料，采用客观分析和数值模拟的手段，分析研究两支流系的相互作用过程，寻找其中存在的规律，探讨二者相互影响的内在机制，探寻这一相互作用过程对南海和印尼海的气候效应。

太平洋-印度洋贯穿流是两大洋水体、热盐交换的重要通道。已有的研究表明其穿越复杂的印尼诸海峡时存在多个分支，主要包括穿越望加锡海峡的印尼贯穿流和连接南海西边界流和卡里马塔海峡的南海分支。本项目与其他项目合作在太平洋-印度洋贯穿流海域组织实施了7次联合观测，获取了卡里马塔海峡、巽他海峡、望加锡海峡和龙目海峡多站点水文连续观测资料。基于这些观测资料，研究了关键海峡通道的水文特征，计算分析了太平洋贯穿流各分支的流量及其季节和季节内变化规律，初步分析了其年际变化特征。基于卫星遥感资料研究了这一海域的季节内信号的传播过程，并分析了它与赤道印度洋季节内变化的关系。采用示踪法结合OFES资料研究了卡里马塔海峡和望加锡海峡水体在印尼海的运移过程。借助数值模式进行了针对卡里马塔海峡和望加锡海峡的诊断实验，分析了两个海峡之间的相互作用过程，初步探讨了其内部机制及其对南海和印尼海的影响。这些研究成果是开展印尼海海洋动力学研究的基础素材，能为该海域的船舶航行保障以及环境保护等提供重要的科学参考。