21 ka以来帝汶海区钻孔堆叠记录的古海洋学意义

印尼穿越流是连接西太平洋和印度洋的唯一载体，与东亚季风和ENSO活动密切相关。帝汶海区是印尼穿越流的主要出口之一，该区不同钻孔末次冰期以来的古海洋学记录显示在长时间尺度上变化存在着很高的相似性。为了捕捉出口处印尼穿越流的平均信号，本研究将这些记录进行堆叠，并与其他海区的钻孔记录进行对比，探讨印尼穿越流对东亚季风和ENSO活动的响应。总体上，堆叠记录较为精准地复制了各个钻孔记录的信息。帝汶海区表层海水温度堆叠记录与其他海区钻孔记录对比显示末次冰期至12~6 ka期间帝汶海可能位于暖池范围内，而晚全新世时位于暖池的边缘；温跃层深度、海水温度和盐度堆叠记录揭示自末次冰期以来印尼穿越流温跃层流呈现逐渐强化的趋势。结合现代水文资料和堆叠记录与其他古海洋古气候记录的对比等，本文推测了不同时期ENSO的冷暖期状态以及东亚季风对印尼穿越流的影响方式和过程。

Stacked records of Timor Sea cores over the last 21 ka and their paleoceanographic significance

Indonesian Throughflow(ITF) is the unique conveyor transporting upper waters from the western Pacific to the Indian Ocean and hence regulates heat and fresh water budgets between the oceans. Change in the ITF, including its upper water stratifying, transporting volume and intensity, is closely related to East Asian monsoon and El Niño -Southern Oscillation(ENSO) activities. The Timor Passage is of key importance among exits of the ITF to the Indian Ocean. Study on cores from the Timor Sea thus provides insightful understanding of ITF history. In this study, we stack the records from the Timor Sea that we reconstructed in the past years and investigate changes in the ITF and its paleoceanographic significance. Motivation to stack Timor Sea records is firstly due to the fact that these records are alike in a common trend at a long-term timescale and their differences are very likely analogs of modern differences among coring sites. For instance, sea surface and thermocline temperatures from Core SO18460 were the lowest ones and those from Core SO18473 the highest ones in particular during the last glacial and deglaciation. This feature coincides with what we see in the modern profiles at the coring sites. Secondly, all of the records from which we try to get stacked records were performed in the same laboratory using the same methods, as is helpful for reducing the errors of stacked records due to inter-lab difference. Thirdly, a stacked record expresses more general information of the ITF outflow variability and provides an advantage for comparison with records from adjacent seas.