Tracking the ancient Indian monsoon: investigating the geochemistry of deep-sea sediments from the Bay of Bengal and Andaman Sea

追踪古印度季风：研究孟加拉湾和安达曼海深海沉积物的地球化学

• 批准号: 2240039
• 金额: --
• 依托单位: UNIVERSITY OF EXETER
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2240039
• 关键词: Tracking; ancient; Indian; monsoon; investigating

The Indian monsoon is one of the most powerful meteorological phenomena on the planet, affecting the lives of over a billion people. However, its behaviour in the near future under the influence of anthropogenic climate change is uncertain. Can we use lessons from the geological past to further our understanding of monsoon sensitivity to climate change? Using marine sediments recovered from the Bay of Bengal and the Andaman Sea in 2015, and by applying cutting-edge geochemical techniques, we will reconstruct monsoon behaviour during the Plio-Pleistocene. The late Pliocene (~3.5 million years ago) is the most recent period in Earth's history with similar elevated global temperatures and CO2 levels to those predicted for the coming century, and may serve as a useful analogue for near-future climate states. The latest Pliocene to earliest Pleistocene (~3.0-2.4 million years ago) was a time of great global change, witnessing the descent into Northern Hemisphere glaciation ("iNHG") concurrent with a significant drop in CO2. Understanding the response of the Indian monsoon system to iNHG will allow us to test ideas about monsoon sensitivity to evolving boundary conditions such as ice volume and CO2 levels. The overarching aim is to produce one of the first orbital-resolution reconstructions of the past behaviour of the Indian Monsoon in this region during the Late Pliocene-early Pleistocene. During the project you will learn to apply a combination of sophisticated organic and inorganic geochemical proxies to new deep-sea sediment archives recovered from the Bay of Bengal and Andaman Sea during International Ocean Discovery Program (IODP) Expedition 353. IODP is the world's largest internationally collaborative research organisation and you have the benefit of being immersed within this broad research community. There is ample opportunity for you to develop the project according to your own interests and strengths, with the prospect of applying a range of organic biomarker proxies (e.g., TEX86, UK37, LDI, compound-specific stable isotopes etc.) as well as foraminifera-based proxies (stable isotopes, trace elements etc.) to interrogate past monsoon variability. These new geochemical records will be compared to pollen, charcoal, and microfossil assemblage data from the same samples, generated by international research partners, which will allow a holistic picture of orbitally-paced climate change in the region to be constructed.You will be embedded within the Deep Time Global Change group at the University of Exeter under the supervision of Drs Littler and Bailey, where facilities for the preparation of sediments for biomarker analysis, along with sediment and foraminifera processing and picking, are available. The student will benefit from substantial involvement with co-supervisors from 3 other institutions, and will have the opportunity to spend significant amounts of time generating organic geochemical data at Bristol, stable isotope data at BGS, and trace element data at the Open University, commensurate with their research interests.

印度季风是地球上最强大的气象现象之一，影响着超过10亿人的生活。然而，其在不久的将来在人为气候变化影响下的行为是不确定的。我们能否利用过去地质学的教训来进一步了解季风对气候变化的敏感性？利用2015年从孟加拉湾和安达曼海回收的海洋沉积物，并通过应用尖端的地球化学技术，我们将重建上新世-更新世期间的季风行为。上新世晚期（约350万年前）是地球历史上最近的一个时期，全球气温和二氧化碳水平升高与下一个世纪的预测相似，并且可以作为近期气候状态的有用模拟。上新世末至更新世末（约300 - 240万年前）是全球发生巨大变化的时期，见证了北方半球冰川作用（“iNHG”）的下降，同时二氧化碳显著下降。了解印度季风系统对iNHG的响应将使我们能够测试季风对不断变化的边界条件（如冰量和CO2水平）的敏感性。总体目标是产生第一个轨道分辨率重建的印度季风在这一地区的过去行为在上新世晚期-更新世早期。在该项目中，您将学习将复杂的有机和无机地球化学代理相结合，应用于国际海洋发现计划（IODP）353远征期间从孟加拉湾和安达曼海回收的新深海沉积物档案。IODP是世界上最大的国际合作研究组织，您可以沉浸在这个广泛的研究社区中。您有充分的机会根据自己的兴趣和优势开发项目，前景是应用一系列有机生物标志物代理（例如，TEX 86、UK 37、LDI、化合物特异性稳定同位素等）以及基于有孔虫的代用品（稳定同位素、微量元素等）来研究过去的季风变化。这些新的地球化学记录将与国际研究合作伙伴从相同样本中获得的花粉、木炭和微体化石组合数据进行比较，这将有助于构建该地区轨道节奏气候变化的整体图景。您将在Littler和Bailey博士的监督下嵌入埃克塞特大学的深时全球变化小组，那里有设施可供生物标志物分析准备沉积物，沿着沉积物和有孔虫的处理和挑选。学生将受益于与来自其他3个机构的共同主管的大量参与，并将有机会花费大量的时间在布里斯托生成有机地球化学数据，在BGS稳定同位素数据，并在开放大学微量元素数据，与他们的研究兴趣相称。