Paleobiogeochemistry of marine sediments

海洋沉积物的古生物地球化学

• 批准号: 288200-2011
• 负责人: Kienast, Markus
• 金额: $ 2.4万
• 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: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=571365
• 关键词: Paleobiogeochemistry; marine; sediments

The sediments on the sea floor are natural archives of past climate and ocean variability. I propose to unravel the information preserved in these records by determining the contents of various organic remains and mineral and chemical properties, so- called proxies. The key to my novel contributions to paleo-oceanographic research is a multi-proxy approach, using a wide range of proxies, which enables my group to differentiate between local and global climate signals, and to establish phasing (i.e. causal) relationships between different components of the climate system. Research in my group has two primary long-term goals: to understand more fully the importance of the tropical Pacific Ocean in past global climate change, and to establish a thorough understanding of nitrogen isotope evidence for past changes in the oceanic nitrogen inventory. The equatorial Pacific is fundamental to Earth's climate system, and has been purported to be instigator, amplifier and mediator of past global climate change on inter-annual to multi-millennial time-scales. For example, the El Niño Southern Oscillation (ENSO) dominates the inter-annual variability of the tropical Pacific today, with tele-connections affecting climate worldwide, and it has thus been proposed that past global climate change could have been modulated by "ENSO-like" variations in the mean state of the tropical Pacific. My cross-disciplinary research into the systematics of nitrogen isotope evidence for past changes in the oceanic N cycling and inventory will shed light on the over-arching question whether or not biogeochemical changes, such as nitrate cycling are the primary cause for changes in the oceanic sequestration of atmospheric CO2 on multi-millennial time-scales. This kind of multi-proxy reconstruction of the full range of the spatial and temporal variability of the ocean and atmosphere and the interrelation between various components of Earth's climate system is required for validating current climate models and for establishing a 'background' state against which potential anthropogenic influences will have to be measured.

海底的沉积物是过去气候和海洋变异性的自然档案。我建议通过确定各种有机残留物，矿物质和化学性质（所谓的代理）的内容来阐明这些记录中保留的信息。我对古细节研究的新颖贡献的关键是使用广泛的代理，使我的小组能够区分本地和全球气候信号，并建立相位（即因果关系）（即因果关系）之间的关系（即，气候系统的不同组成部分）。 我小组的研究有两个主要的长期目标：更充分地了解热带太平洋在过去的全球气候变化中的重要性，并建立对氮的透彻理解 同位素证据证明了海洋氮库存的过去变化。赤道太平洋至关重要 地球的气候系统，据称是过去全球气候的煽动者，放大器和调解人 更改年间到多千年的时间尺度。例如，厄尔尼诺南部振荡（ENSO） 当今热带太平洋的青年际变化占主导地位，电视连接影响攀登 全球范围内，因此有人提出，过去的全球气候变化本可以受到调整 热带太平洋平均状态的“ ENSO样”变化。我对 氮同位素证据的系统学证据证明了海洋N循环和库存的过去变化将阐明生物地球化学变化（例如硝酸盐循环）是否是多千年时间表大气CO2海洋序列化的主要原因。 需要测量这种多种范围的海洋和大气的空间和临时变异性以及地球气候系统各种组成部分之间的相互关系的多种多种重建，以验证当前的气候模型并建立“背景”状态，以衡量潜在的人为影响的“背景”状态。