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，影响着超过十亿人的生活。然而，它在不久的将来在人为气候变化影响下的行为是不确定的。我们能否利用地质历史的教训来进一步了解季风对气候变化的敏感性？我们将利用 2015 年从孟加拉湾和安达曼海回收的海洋沉积物，并应用尖端的地球化学技术，重建上皮里奥-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时期，其全球气温和二氧化碳水平升高与下个世纪的预测相似，并且可以作为近期气候状态的有用类比。上新世末期至更新世末期（约 3.0-240 万年前）是全球发生巨大变化的时期，见证了北半球冰川期（“iNHG”）的下降，同时二氧化碳含量显着下降。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（例如冰量和二氧化碳水平）的敏感性的想法。总体目标是对上新世晚期至更新世早期印度季风在该地区过去的行为进行首次轨道分辨率重建。在该项目期间，您将学习如何将复杂的有机和无机地球化学代理组合应用于国际海洋发现计划 (IODP) 第 353 次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，您将受益于融入这个广泛的研究社区。您有充足的机会根据自己的兴趣和优势开发项目，并有望应用一系列有机生物标志物代理（例如 TEX86、UK37、LDI、特定化合物的稳定同位素等）以及基于有孔虫的代理（稳定同位素、微量元素等）来询问过去的季风变化。这些新的地球化学记录将与国际研究合作伙伴生成的相同样本的花粉、木炭和微化石组合数据进行比较，这将有助于构建该地区轨道气候变化的整体图景。您将在利特勒和贝利博士的监督下加入埃克塞特大学的深时全球变化小组，那里有准备生物标记沉积物的设施 可以进行分析以及沉积物和有孔虫加工和采摘。学生将受益于与其他 3 个机构的共同导师的大量参与，并将有机会花费大量时间在布里斯托尔生成有机地球化学数据、在 BGS 生成稳定同位素数据以及在开放大学生成微量元素数据，这些数据与他们的研究兴趣相称。