Impact of the Keweenaw Current on Cross-Margin Transport in Lake Superior Physical Processes, Chemical Gradients, and Biological Communities

基韦诺洋流对苏必利尔湖物理过程、化学梯度和生物群落跨界输运的影响

• 批准号: 9712869
• 负责人: Changsheng Chen
• 金额: $ 67.56万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-15 至 2001-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9712869&HistoricalAwards=false
• 关键词: Impact; Keweenaw; Current; Cross; Margin

9712869 Chen Research will be undertaken in response to an Announcement of Opportunity (NSF 97-38) for Coastal Studies in the Great Lakes. This is a collaborative research project involving eleven investigators from five academic research institutions. The research is being conducted under the auspices of the NSF Coastal Ocean Processes (CoOP) program and the NOAA Coastal Ocean Program. This collaborative, interdisciplinary 5-year research program will entail an integrated program of field and laboratory studies and mathematical modeling to quantify the role of coastal currents and thermal fronts in mediating cross-margin transport in Lake Superior. The western shore of Lake Superior's Keweenaw Peninsula exhibits a dramatic coastal jet known as the Keweenaw Current. A strong, shore-parallel density front, the thermal bar, also is characteristic of this region and persists long into the summer. The goal of the proposed work is to determine the physical, chemical, and biological effects that arise from the intense physical forcing on this system, and specifically, to elucidate how these effects interact temporally and spatially to define distinct nearshore and offshore environments in Lake Superior. This project represents the first effort to model coupled physical, chemical, and biological processes in the coastal zone of Lake Superior where both vertical and horizontal thermal structure and transport processes are important. The research team is divided into three subgroups: Physical Processes, Chemical Gradients, and Biological Communities. The Physical Processes group will examine the relative importance of all forcing factors (e.g., wind-driven variability, baroclinic instability) that govern cross margin transport using in situ observations, numerical modeling, and satellite observations. The Chemical Gradients group will characterize nearshore-offshore differences in distributions of chemical species, evaluate chemical tracers of wat er and sediment movement, and investigate differences (inshore vs. offshore) in chemical cycles induced by the current. The Biological Communities group will determine how gradients in primary production, trophic structure, and rates of material transformation develop. All three groups will interact closely throughout the project to obtain and share complementary data sets and to derive a coupled physical/chemical/biological model of the system. The detailed, process-level understanding achieved by this project will advance our quantitative understanding of the processes that regulate the transport, transformation and fate of biologically, chemically and geologically important matter in coastal regions and provide a firm basis for future management decisions on how best to preserve the pristine nature of Lake Superior. This particular project will contribute to the activities of the Physical Processes subgroup that will measure currents, thermal, and density structure in order to define the spatial and temporal extent of the Keweenaw Current and thermal bar. This research will also develop and test a coupled biological-physical model for the Keweenaw Current environment.

9712869 Chen Research将于响应宣布大湖沿海研究的机会（NSF 97-38）。 这是一个合作研究项目，涉及来自五个学术研究机构的11位研究人员。 这项研究是根据NSF沿海海洋过程（COOP）计划和NOAA沿海海洋计划的主持人进行的。 这项合作，跨学科的5年研究计划将需要一项综合实验室和实验室研究和数学建模计划，以量化沿海电流和热阵线在介导苏必利尔湖跨微边缘运输中的作用。 苏必利尔湖的西方海岸半岛的西岸展示了一种戏剧性的沿海喷气式喷气式飞机，称为Kewonaw电流。 强，岸并行的密度前线，热条，也是该区域的特征，并且在夏季长期存在。拟议工作的目的是确定由该系统上强烈的物理强迫产生的物理，化学和生物学效应，特别是，阐明这些效果如何在时间和空间上相互作用，以定义苏必利尔湖的近岸和近海环境。 该项目代表了苏必利尔湖沿海地区耦合物理，化学和生物过程的首次努力，在该沿海地区垂直和水平的热结构以及运输过程都很重要。 研究团队分为三个亚组：物理过程，化学梯度和生物群落。 物理过程组将检查所有强迫因子（例如，风向变异性，斜压不稳定性）的相对重要性，该因素使用原位观测，数值建模和卫星观测来控制跨边缘传输。 化学梯度组将表征化学物种分布的近岸近岸差异，评估水和沉积物运动的化学示踪剂，并研究由电流引起的化学周期的差异（近海与海上）。 生物社区组将确定一级生产，营养结构和物质转化速率的梯度如何发展。这三个组将在整个项目中紧密相互作用，以获取和共享互补的数据集并得出系统的物理/化学/生物学模型。 该项目实现的详细，过程级别的理解将提高我们对调节沿海地区生物学，化学和地质上重要问题的运输，转型和命运的过程的定量理解，并为未来的管理决策提供了关于如何最好地保留苏必利尔湖原始性质的未来管理决策。 这个特定的项目将有助于物理过程亚组的活动，该过程将测量电流，热和密度结构，以定义Keweenaw电流和热条的空间和时间范围。这项研究还将为Keweenaw当前环境开发和测试一个耦合的生物物理模型。