10² to 10³ year scale variability of the El Niño/Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) in the eastern Indian Ocean over the last 30,000 years

最近的研究一致认为，印度尼西亚群岛在现在和过去的全球气候中发挥着关键作用。然而，在重建区域气候及其全球影响时，特别是在百年至千年的时间尺度和气候突变期间，基于代理的结果和模拟结果都有所不同。这些研究强调了需要迄今为止缺少的印度尼西亚群岛东印度洋西部和西南部的高分辨率代用证据，这是热带气候动力学的关键区域，特别是在印度洋偶极子（IOD）和厄尔尼诺-南方涛动（ENSO）方面。使用基于有孔虫的地球化学代理在高分辨率的沉积物岩心从关闭W-和SW-印度尼西亚，我们的目标是重建过去的变化，强烈影响IOD/ENSO事件的区域水文。我们将解释这些结果，以重建过去的IOD强度和它的联系，ENSO在上述时间尺度上。尽管最近在了解厄尔尼诺/南方涛动和印度洋间日变化的年际方面取得了进展，但其长期运行的基本特征及其与全球气候的联系至今仍难以弄清。我们的研究将为这些现象在不同气候状态和边界条件下的长期行为提供线索。

Recent studies agree that the Indonesian Archipelago plays a key role in present and past global climate. However, both proxy-based and modelling results differ when reconstructing the regional climate and its global implications, particularly on centennial to millennial timescales and during abrupt climate changes. These studies underline the need for hitherto missing high-resolution proxy evidence from the eastern Indian Ocean W and SW of the Indonesian Archipelago, a key region in tropical climate dynamics especially with regard to the Indian Ocean Dipole (IOD) and El Niño-Southern Oscillation (ENSO). Using planktonic foraminifera-based geochemical proxies in high-resolution sediment cores from off W- and SW-Indonesia, we aim to reconstruct past variations in the regional hydrography that is strongly affected by IOD/ENSO events. We will interpret these results in order to reconstruct past intensity of the IOD and its link to ENSO on the above mentioned time-scales. Despite recent progress in understanding the inter-annual aspects of ENSO and IOD, the basic characteristics of their long-term operation and their link to global climate are so far elusive. Our study will provide clues on the long-term behavior of these phenomena under different climate states and boundary conditions.