末次冰期以来印度尼西亚穿越流在东印度洋的热传输过程及其古气候意义

One of the major features in the ocean circulation of the Indonesian Seas, which connect the Western Pacific Warm Pool and Indian Ocean Warm Pool，is the Indonesian Throughflow (ITF). As part of the global conveyor belt, the ITF plays an important role in the large scale ocean-atmosphere interaction in the tropical region. The transport and thermohaline stratification of the ITF can influence the heat and freshwater budgets of both the Pacific and Indian Oceans, and alter patterns of heat and water vapor exchange with the atmosphere on a global scale. Here we propose a high-resolution paleoceanographic and paleoclimatic study to reconstruct the heat transport processes of the ITF since the last glaciation. Multi-cores which are collected in the main ITF pathways of the Timor Sea, Sunda Strait and the South Equatorial Current region in the eastern Incian Ocean will be investigated using micropaleontological, sedimentological and geochemical methods. The results of these analyses will be used to obtain detailed information about the changes in the stratification structure of various pathways of the ITF and hence in the heat transport processes since the last glaciation. Through comparison with existing paleoceanographic and paleoclimatic data in the eastern Indian Ocean, we will explore the influence of the heat transport processes from western Pacific Ocean to eastern Indian Ocean on the variations in heat budget of the eastern Indian Ocean. This study is also expected to provide a basis for testing the ocean general circulation model, and have implications for predicting the future ocean-climate change.

印度尼西亚海地处印度洋-太平洋暖池区的中间地带，是大尺度海气耦合系统的关键位置, 在全球气候演变中具有重要作用。印度尼西亚穿越流的输运和热盐分层影响着太平洋和印度洋的热量和淡水平衡，在全球尺度上改变了海洋和大气的热量和水汽交换模式，通过对地球气候系统发挥临界控制在全球热传输循环中起着关键作用。本次研究拟通过帝汶海道、巽他海峡以及东印度洋南赤道流区等印度尼西亚穿越流主要输运通道上多支岩芯的古海洋与古气候学研究，建立印度尼西亚海区及东印度洋南赤道流区末次冰期以来高分辨率的地层年代框架，通过提取古海洋与古气候演变信息，重建东印度洋末次冰期以来高分辨率的印度尼西亚穿越流热传输过程，对比东印度洋的古海洋与古气候变化特点，初步探讨印度尼西亚穿越流自西太平洋向东印度洋的热传输过程对东印度洋古气候的影响，为验证海洋环流模拟结果，预测未来海洋－气候变化提供基础资料与科学依据。

印度尼西亚穿越流通过印度尼西亚海内众多复杂连通的海峡从太平洋进入到印度洋，是全球大洋热盐环流传送带的关键环节，维持着全球大洋间的物质、动量和能量平衡。印尼穿越流的输运和热盐分层影响着太平洋和印度洋的热量和淡水平衡，在全球热传输循环中起着关键作用。本研究通过帝汶海道、巽他海峡以及东经90°海岭上的南赤道流区等印尼穿越流主要输运通道上多支岩心的古海洋与古气候学研究，建立了研究区末次间冰期以来高分辨率的地层年代框架；对比印尼穿越流主要传输通道上各区的上层水体结构与性质特征及成因，揭示了印尼穿越流自西太平洋进入东印度洋的输运过程有着连续一致的变化趋势，其上层水体结构与性质受轨道周期性调控，印尼穿越流的热传输过程因而发生周期性变化；将东印度洋区与西太平洋暖池中心区表层、温跃层水古温度进行较为系统的对比分析，揭示了末次间冰期以来印尼穿越流在印－太平洋区热传输过程中的作用及其对东印度洋古气候的可能影响。