Global ocean circulation during the late Quaternary: Paleoceanographic constraints from the Western Equatorial Pacific

晚第四纪全球海洋环流：来自西赤道太平洋的古海洋学限制

• 批准号: RGPIN-2022-03064
• 负责人: Kienast, Markus
• 金额: $ 3.13万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=761596
• 关键词: Global; ocean; circulation; during; late

The ocean initiates, amplifies and mediates global climate change on time scales ranging from less than a year to thousands of years. The overarching long-term goal of my research program is to characterize and quantify large-scale ocean circulation both in the modern and past ocean. Large-scale ocean circulation plays a pivotal role in global climate, for example through the redistribution of heat and its control on the partitioning of carbon dioxide, CO2, between the ocean and atmosphere. My research will, therefore, provide uniquely important observational constraints on rates and amplitudes of climate change. Specifically, I seek to characterize the dynamic relationship between the cross-hemispheric and inter-basin ocean exchanges in the Western Equatorial Pacific during the late Quaternary (the last 150,000 years). The Western Equatorial Pacific is the world's only "water mass crossroad", where surface waters flowing from the Pacific to the Indian Ocean through the Indonesian Throughflow are overriding deeper waters flowing from the southern to the northern hemispheres. My research of this pivotal - but much understudied - region of the world's ocean will address critical gaps in our understanding, with a particular focus on three interlinked short-term objectives: 1) How did the Indonesian Throughflow vary in the past? 2) What is the effect of changing water mass sources on the nutrient conditions along the vast equatorial Pacific? 3) How did the circulation of Antarctic-sourced intermediate and deep waters change during the last glacial-interglacial cycle? The primary focus of the overall research program will be on four time intervals, which together constrain the full dynamic range of ocean and climate change during the late Quaternary: a) the last 2,000 years, to contextualize ongoing and projected global climate change; b) the early Holocene insolation maximum (9,000 - 6,000 years ago), to assess the effect of regional climate on the Indonesian Throughflow compared the last 2,000 years; c) the last glacial-interglacial transition (25,000 - 10,000 years ago), to establish rates and amplitudes of change during the last natural global warming event; and d) the last interglacial period (125,000 - 115,00 years ago), to compare to the present interglacial. Understanding past ocean and climate variability is key to understanding the present-day ocean-climate system and for modelling future global climate change in the Anthropocene. My research program will continue to contribute critically needed quantitative constraints on past ocean and climate change. The research program will also provide advanced education and training in cutting-edge, high-quality research, which will ensure future research careers and employment of my students in impactful positions related to natural science.

海洋启动，放大和调解了不到一年到数千年的时间尺度的全球气候变化。我的研究计划的总体长期目标是表征和量化现代和过去海洋中的大型海洋循环。大规模海洋循环在全球气候中起着关键作用，例如，通过热量重新分布及其对海洋和大气之间二氧化碳二氧化碳二氧化碳二氧化碳分配的控制。因此，我的研究将对气候变化的比率和幅度提供独特的重要观察限制。 具体而言，我试图表征西方赤道太平洋的跨膜和巴辛间海洋交流（最近150，000年）之间的动态关系。西部赤道太平洋是世界上唯一的“水质十字路口”，那里的地表水从太平洋流到印度洋，穿过印度尼西亚人遍布印度洋，这是从南部流向北半球的更深水域。我对这个关键的研究（但要忽略的）世界的研究将解决我们理解中的关键差距，特别关注三个相互联系的短期目标：1）印尼过去的遍布在过去有何不同？ 2）更换水质量来源对沿着广阔赤道太平洋养分条件的影响是什么？ 3）在最后一个冰川间冰期周期中，南极采购的中间和深水的循环如何变化？整个研究计划的主要重点将是四个时间间隔，这在第四纪晚期期间共同限制了海洋和气候变化的全部动态范围：a）最近2000年，以将持续和预计的全球气候变化背景而出； b）最多全新世的突发性（9,000至6，000年前），以评估当地气候对印尼遍及流量的影响，相比之下； c）最后一次自然全球变暖事件期间建立变化的速率和变化率； d）最后一次冰间期（125,000-115,00年前），与目前的冰川间相比。了解过去的海洋和气候变异性是了解当今海洋气候系统以及对人类世的未来全球气候变化进行建模的关键。我的研究计划将继续为过去的海洋和气候变化做出迫切需要的定量限制。该研究计划还将提供高级，高质量研究的高级教育和培训，这将确保未来的研究职业和与自然科学相关的有影响力职位的学生的就业。