Modern and Deep Time oceanography (SSC, SLC) & climatology (SST): insight from brachiopod archives

现代和深时海洋学（SSC、SLC）

• 批准号: RGPIN-2015-05282
• 负责人: Brand, Uwe
• 金额: $ 1.97万
• 依托单位: Brock University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=681906
• 关键词: Modern; Deep; Time; oceanography; SSC

Climate change and the postulated associated biotic crisis are gripping the 21st century, and we are in desperate need for critical information from extremely sensitive environments - warm and cold - to better document the impacts of global warming on our society. Canada's large northern polar region may undergo some dramatic and drastic changes in a relatively short time period. ***As part of my program, I plan to study compositional changes and environmental relationships in modern and ancient brachiopods (lampshells) - from extreme environments such as tropical, polar and deep regions of the global ocean. This baseline information will be critical in determining the rate of climate change for highly sensitive environments and to assess the impact of the rate of change. Insight for impacts, effects and outcomes will be sought from ancient brachiopods present during climatic events of the geologic past such as the Late Paleozoic Ice Age, which dwarfs the last ice age, from the end Permian mass extinction event, with its catastrophic warming that caused the - almost life-ending - biotic crisis in geologic history, and the end Triassic mass extinction, which drastically changed life on our planet with the rise of the dinosaurs. ***Lampshells secrete shells consisting of calcite that is relatively stable to the vagaries of time but changes its composition with changes in the composition of the ambient seawater. Equilibrium incorporation of trace elements and stable isotopes into shell calcite and coupled with isotope thermometry are fundamental underpinnings of brachiopod-based paleoclimatology and paleoceanography (Brand et al., 2013, 2014). Thus, if the chemistry of seawater changes due to acidification brought about by the incorporation of anthropogenic carbon dioxide, we can document these changes by analyzing the trace and isotope chemistry of brachiopod shells. This principle applies to many other climate-change related factors, such as the melting of the ice caps and sea ice and warming of the oceans, and this information will be stored by brachiopods in their shell calcite.***Brachiopods are excellent recorders (archives) of climatic events affecting the oceans and the Earth. Detailed geochemical analyses supplemented with nanostructural analysis of brachiopod shells from specific and focused events/horizons will provide us with critical information of these events in the geologic past, and of changes in the past 100 years since the start of the industrial revolution. This work will be immensely important to the fields of paleoclimatology and paleoceanography, and may influence policy decisions regarding our sensitive and fragile polar region and its resource and tourism developments, shelf areas in the Canadian Arctic, and sovereignty over the Canadian Arctic Ocean.*** **

气候变化和假定的相关生物危机正在困扰着21世纪，我们迫切需要从极端敏感的环境（温暖和寒冷）中获得关键信息，以便更好地记录全球变暖对我们社会的影响。加拿大广阔的北极地区可能在相对较短的时间内经历一些戏剧性和剧烈的变化。***作为我项目的一部分，我计划研究现代和古代腕足动物（灯壳）的成分变化和环境关系——来自极端环境，如热带、极地和全球海洋的深海地区。这一基线信息对于确定高度敏感环境的气候变化速度和评估变化速度的影响至关重要。对影响、影响和结果的见解将从地质过去气候事件中出现的古代腕足类动物中寻求，比如晚古生代冰河时代，它使最后一个冰河时代相形见绌，从二叠纪末期的大灭绝事件中，它的灾难性变暖导致了地质历史上几乎结束生命的生物危机，以及三叠纪末期的大灭绝，随着恐龙的兴起，它彻底改变了我们星球上的生命。***灯壳分泌出方解石组成的贝壳，方解石对时间的变化相对稳定，但其成分随着周围海水成分的变化而变化。微量元素和稳定同位素在壳方解石中的平衡结合以及同位素测温是腕足动物古气候学和古海洋学的基础（Brand et al., 2013, 2014）。因此，如果由于人为二氧化碳的掺入导致海水酸化而发生化学变化，我们可以通过分析腕足类贝壳的痕量和同位素化学来记录这些变化。这一原理适用于许多其他与气候变化有关的因素，如冰盖和海冰的融化以及海洋的变暖，这些信息将被腕足类动物储存在它们的壳方解石中。腕足类动物是影响海洋和地球的气候事件的优秀记录者（档案）。详细的地球化学分析，加上对特定事件/视界的腕足类壳的纳米结构分析，将为我们提供过去地质时期这些事件的关键信息，以及自工业革命开始以来过去100年的变化。这项工作将对古气候学和古海洋学领域非常重要，并可能影响有关我们敏感和脆弱的极地地区及其资源和旅游开发，加拿大北极大陆架区域以及加拿大北冰洋主权的政策决定。* * * * *