Collaborative Research: River plume-cape interaction - Plume separation from the coastal wall, vorticity generation and fresh water retention

合作研究：河流羽流-海角相互作用——羽流与海岸壁的分离、涡度的产生和淡水保留

• 批准号: 1948777
• 负责人: Robert Chant
• 金额: $ 32.76万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1948777&HistoricalAwards=false
• 关键词: Collaborative; Research; River; plume; cape

This project will examine the interaction of a stratified coastal plume with a cape, using a combined observational and modeling approach. High-resolution shipboard surveys and moored instrumentation near Point Reyes, CA, will measure the circulation and evolution of the San Francisco Bay Plume under a range of wind and river discharge conditions. Combined numerical model simulations and observations will quantify the dynamical balances and residence times of the Plume downstream of the Cape. Idealized simulations will permit expansion of results across parameter space, to understand both the controlling dynamics and conditions affecting plume separation and retention times of stratified plumes in the lee of capes in the coastal ocean. Coastal plumes are a key component of shelf circulation, and important conduits for transport of pollutants, nutrients, water masses and the organic carbon they contain. Understanding the factors influencing plume separation and retention times will contribute to understanding fates of such societally important ocean constituents.Complex coastal geometries, such as capes and submarine banks, can lead to significant hydrodynamic disturbances of buoyant coastal flows. Such plumes are key components of shelf circulation and coastal ocean biogeochemistry and marine ecosystems, so their dynamics and fate are critical to understand. This project will quantify the interaction between the San Francisco Bay Plume in the vicinity of Point Reyes, CA, under a range of wind and river discharge conditions, using shipboard, moored, and drifter field observations, combined with realistic and idealized numerical modeling studies. The main objectives are to: (1) obtain detailed measurements of plume hydrography, along- and cross-stream velocities and transports near a cape, under a range of river discharge and wind-forcing conditions, (2) identify the conditions for plume separation from the coast and eddy generation in the lee of a cape, (3) quantify the retention time scales downstream of the cape associated with the generated eddies, and (4) investigate the dominant momentum balances that control far-field dynamics as the plume interacts with a cape. Although plumes encompass a small area of the ocean surface, they are the boundary condition for larger scale shelf circulation, and thus their evolution is critical to understand and represent realistically in models. This project will result in better understanding of the fate and transport of pollutants, nutrients and water masses in the ocean, contribute observational datasets, models, and analysis tools to the science community, and will provide critical research capacity for two early career scientists.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该项目将采用观测和建模相结合的方法，研究分层的沿海羽流与海角的相互作用。加利福尼亚州雷斯岬附近的高分辨率船上调查和系泊仪器将测量旧金山湾羽流在一系列风和河流排放条件下的环流和演变。结合数值模型模拟和观测将量化海角下游羽流的动态平衡和停留时间。理想化的模拟将允许跨参数空间扩展结果，以了解影响羽流分离的控制动力学和条件以及沿海海角背风处分层羽流的保留时间。沿海羽流是陆架循环的关键组成部分，也是污染物、营养物、水团及其所含有机碳运输的重要渠道。了解影响羽流分离和保留时间的因素将有助于了解这些对社会重要的海洋成分的命运。复杂的沿海几何形状，例如海角和海底浅滩，可能会导致沿海浮力流的严重水动力扰动。这些羽流是陆架环流、沿海海洋生物地球化学和海洋生态系统的关键组成部分，因此了解它们的动态和命运至关重要。该项目将利用船上、系泊和漂流现场观测，结合现实和理想化的数值模型研究，量化加利福尼亚州雷斯岬附近的旧金山湾羽流在一系列风和河流排放条件下之间的相互作用。主要目标是：(1) 在一系列河流流量和风力条件下，获得羽流水文学、沿流和横流速度以及海角附近传输的详细测量结果，(2) 确定羽流分离的条件从海角背风处的海岸和涡流生成，(3) 量化与生成的涡流相关的海角下游的保留时间尺度，(4) 研究控制远场动力学的主要动量平衡：羽流与斗篷相互作用。尽管羽流覆盖了海洋表面的一小部分区域，但它们是更大规模的陆架环流的边界条件，因此它们的演化对于理解和在模型中真实地表示至关重要。该项目将有助于更好地了解海洋中污染物、营养物和水团的命运和传输，为科学界贡献观测数据集、模型和分析工具，并将为两位早期职业科学家提供关键的研究能力。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。