Collaborative research: Sources and circulation of intermediate and deep waters and their role in Campanian-Maastrichtian global cooling

合作研究：中层水和深层水的来源和循环及其在坎帕尼亚-马斯特里赫特全球变冷中的作用

• 批准号: 1261443
• 负责人: Christopher Poulsen
• 金额: $ 19.36万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1261443&HistoricalAwards=false
• 关键词: Collaborative; research; Sources; circulation; intermediate

The late Cretaceous period (83-66 Ma) saw an important climatic transition from the extreme warmth of the early Late Cretaceous to the cooler conditions of the Early Paleocene. Evidence from multiple ocean basins indicates that this transition was accompanied by major changes in ocean circulation. However, the nature of these oceanographic changes and their role in global cooling are the subject of debate. Some interpretations call for expansion of southern component water (SCW) through the global ocean, possibly causing widespread cooling through low-latitude upwelling of cold deep waters. Others suggest shifts in the dominance of regional sources of deep-water formation, including initiation of North Atlantic sources, leading to changes in intra-basinal heat transport and climate. This collaborative research, involving scientists from the University of Missouri-Columbia, the University of Florida, and the University of Michigan, seeks to resolve these controversies. Building on their earlier findings, the researchers will generate new geochemical proxy data from locations that will, in combination with existing data, constrain possible intermediate- and deep ocean sources and circulation modes. They will also evaluate the plausibility of paleoceanographic interpretations through climate model simulations, testing hypotheses regarding the effect of gateways and greenhouse gas concentrations on circulation patterns and deep convection and their links with global climate change. The results of this work will add to our knowledge about the relationship between ocean circulation and global climate change and, in this way, contribute to efforts to predict future climate change. In addition, the researchers will conduct specific activities that contribute to general education and the dissemination of scientific understanding, and the training and mentoring of young scientists including the following: (i) developing short videos to communicate the excitement and novelty of paleoceanographic research to the public, to be featured in displays at natural history museums at the researchers? home institutions, and posted on popular websites, (ii) training graduate students at each of the participating institutions, and (iii) disseminating results through publications, presentations at professional meetings, and by integrating research into lecture material, discussions, and classroom exercises for graduate and undergraduate students.

晚白垩世时期（83-66 Ma）是一个重要的气候转变，从晚白垩世早期的极端温暖到古新世早期的较冷条件。来自多个海洋盆地的证据表明，这种转变伴随着海洋环流的重大变化。然而，这些海洋学变化的性质及其在全球变冷中的作用是辩论的主题。一些解释呼吁通过全球海洋的南部成分水（SCW）的扩张，可能会导致广泛的冷却，通过低纬度寒冷的深层沃茨的上涌。其他人则认为，深水形成的区域来源的主导地位发生了变化，包括北大西洋来源的启动，导致盆地内热量输送和气候的变化。这项合作研究涉及密苏里-哥伦比亚大学，佛罗里达大学和密歇根大学的科学家，旨在解决这些争议。在他们早期发现的基础上，研究人员将从一些地点生成新的地球化学代用数据，这些数据将与现有数据相结合，限制可能的中间和深海来源和环流模式。他们还将通过气候模型模拟评估古海洋学解释的可行性，测试关于网关和温室气体浓度对环流模式和深层对流及其与全球气候变化联系的影响的假设。这项工作的结果将增加我们对海洋环流与全球气候变化之间关系的了解，从而有助于预测未来气候变化的努力。此外，研究人员还将开展具体活动，促进普通教育和传播科学知识，培训和指导青年科学家，包括：（i）制作短视频，向公众宣传古海洋学研究的激动人心之处和新奇，并在研究人员所在地的自然历史博物馆展出。这些方法包括：（i）将研究成果纳入国内研究机构，并在热门网站上发布;（ii）在每个参与机构培训研究生;（iii）通过出版物、在专业会议上的演讲以及将研究成果纳入研究生和本科生的讲座材料、讨论和课堂练习中来传播研究成果。