Collaborative Research: Coastal Ocean Advances in Shelf Transport (COAST): Iron Input and Wind-driven Circulation along the Oregon Coast

俄勒冈州立大学、北卡罗莱纳大学和哥伦比亚大学的研究人员将合作进行一项为期五年的深入研究，将一套独特的观测工具与海洋和大气模型结合起来，调查俄勒冈沿海海洋的环流、生物和化学。该项目在沿海海洋过程（CoOP）计划的支持下，是对东北太平洋风力过程研究机会公告的回应。要研究的俄勒冈大陆架区域在夏季和冬季都对风的作用力有强烈的反应，夏季的平均风向有利于上升，冬季的平均风向有利于下降。通过进行现场实验，结合海洋环流/生态系统和大气模拟，将解决与风驱动系统中跨大陆架运输过程有关的一组科学假设。假设：(1)上升流和下升流射流和锋面的存在局部地改变了表层、底边界层和内部的跨陆架环流；(2)沿海地形变化决定了二维和三维跨陆架运输过程的相对重要性；(3)上升和下降过程中陆架上的湍流型受锋面和急流的影响，且湍流强度足以影响中尺度环流；(4)陆架上初级生产的规模和分布及其随后的海上运输完全由上升流的几何形状控制；(5)沿岸湍流混合的变化控制了初级产量的大小和分布；(6)下流锋面的存在减少了跨大陆架的运输，使得营养物质、微量金属和浮游植物和浮游动物的种子储备在大陆架中部到内部积累，从而在上升流开始时为系统提供了强烈的生物反应。为了解决这些假设，将在两个区域进行密集的观测：一个在地形相对简单的区域，一个在地形突变的区域。高分辨率采样将使用船舶、仪器飞机、一套系泊和陆基海岸雷达进行，以制作高空间分辨率的表面洋流地图。一个高分辨率的三维陆架环流和耦合生态系统海洋模式将用于直接支持实地实验，有助于观测资料的动态综合和相关过程研究。中尺度大气模拟工作将为海洋模式和海洋观测资料的解释提供在空间和时间上连续的地表强迫估计。这些测量汇集了一套独特的观测工具，以前没有同时应用于沿海动力学的研究。与海洋环流/生态系统和大气模型相协调，所提出的努力将大大提高我们对风驱动大陆架跨大陆架运输过程的理解。

9907953van GeenInvestigators at Oregon State University, University of North Carolina, and Columbia University will collaborate on an intensive five-year study to combine a unique set of observational tools and ocean and atmosphere models to investigate the circulation, biology, and chemistry of the Oregon coastal ocean. This project is under the auspices of the Coastal Ocean Processes (CoOP) Program and is in response to an Announcement of Opportunity for Wind-Driven Process Studies in the Northeast Pacific. The area to be studied on the Oregon shelf responds strongly to wind forcing during both summer, when mean winds favor upwelling, and winter, when mean winds favor downwelling. A set of scientific hypotheses related to cross-shelf transport processes in a wind-driven system will be addressed by conducting field experiments together with coordinated ocean circulation/ ecosystem and atmospheric modeling. The hypotheses are: (1) the presence of upwelling and downwelling jets and fronts locally alters cross-shelf circulation in the surface and bottom boundary layers and in the interior; (2) alongshore topographic variations dictate the relative importance of two-dimensional versus three-dimensional cross-shelf transport processes; (3) patterns of turbulence on the shelf during upwelling and downwelling are influenced by fronts and jets, and the levels of turbulence can reach sufficient intensity to influence the mesoscale circulation; (4) the magnitude and distribution of primary production on the shelf and its subsequent transport offshore is controlled solely by the geometry of upwelling; (5) alongshore variations in turbulent mixing control the magnitude and distribution of primary production; and (6) the reduced cross-shelf transport implied by the presence of a downwelling front allows nutrients, trace metals and seed stocks of phytoplankton and zooplankton to accumulate in the mid- to inner shelf, thus priming the system for a strong biological response at the outset of upwelling.To address the hypotheses, intensive observations will be made in two regions: one in a region of relatively simple topography and one in a region of abrupt topography. High-resolution sampling will be conducted using ships, an instrumented aircraft, a set of moorings, and a land-based coastal radar to make high -spatial resolution surface current maps. A high-resolution, three-dimensional shelf circulation and coupled ecosystem ocean model will be used in direct support of the field experiments by contributing to the dynamical synthesis of the observations and for relevant process studies. A mesoscale atmospheric modeling effort will provide estimates of surface forcing, continuous in space and time, for the ocean model and for interpretation of the oceanic observations.These measurements bring together a unique set of observational tools not previously applied simultaneously to the study of coastal dynamics. Coordinated with ocean circulation/ecosystem and atmospheric modeling, the proposed effort will significantly advance our understanding of cross-shelf transport processes on wind-driven continental shelves.