Collaborative Research: Dynamics of Cross-Shelf Plumes under Upwelling Wind Conditions

该项目将通过“浮力羽流”调查陆源河流与开放海洋水域的联系。该项目将评估河流流量、潮汐和风在整个大陆架浮力羽流形成和维持中的作用。为了进行评估，该项目将使用船载测量、自主水面车辆、自主飞行器（无人机）和浮动平台，并辅以计算机模型模拟。该项目将提供陆地和开放海洋过程之间联系的近似值，用于全球尺度模式。该项目还将促进研究型大学和本科学院之间的互动。它将培养研究生，并为本科生提供宝贵的经验。本研究集中在超临界沿海浮力羽流的动力学上，这些羽流在大陆架上斜向扩张。这些浮力羽流在大陆架上输送低盐度的水，并可能被流经大陆架边缘的洋流所携带。浮力羽流受风应力（有利于上升流）和浮力力之间平衡的影响。咸淡水的潮汐脉冲干扰这种动态平衡，产生径向锋，称为次羽流。这些次羽流随后被埃克曼输送平流。数据收集将包括对Winyah湾羽流的4次季节性调查，使用船只（UNOLS船要求）、无人机、自主水面车辆和浮动平台，以获得水流速度、盐度、温度和湍流特性的剖面。只要水平密度梯度突出，惯性周期大于潮汐周期，亚羽锋面就会普遍存在。观测结果将由非流体静力数值模型的数值模拟加以补充。作为更广泛的影响，这项研究将允许将跨大陆架羽流参数化到研究陆地-海洋交换的低分辨率模型中。该项目将资助2名硕士和1名博士研究生，并为几名本科生提供巡游机会。收集的数据及其分析将产生海洋数据分析模块，分发给海洋学界。该项目将由和R1与一所教学机构合作。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The project will investigate the linkage of land-derived riverine waters with open ocean waters via 'buoyant plumes.' The project will assess the role of river discharge, tides and winds in the formation and maintenance of the buoyant plumes throughout the continental shelf. For such assessment, the project will use shipboard measurements, Autonomous Surface Vehicles, Autonomous flying vehicles (drones), and a floating platform that will be complemented by computer model simulations. The project will provide approximations of the linkage between land and open-ocean processes to be used in global-scale models. The project will also facilitate interactions between a research intensive university and an undergraduate college. It will train graduate students and provide valuable experiences to undergraduate students. This study concentrates on the dynamics of supercritical coastal buoyant plumes that expand obliquely across the shelf. These buoyant plumes transport low salinity waters across the continental shelf and can be entrained by ocean currents flowing by the shelf’s edge. The buoyant plumes are influenced by the balance between wind stress (upwelling-favorable) and buoyancy forcing. Tidal pulses of brackish water interfere with such dynamic balance to produce radial fronts referred to as sub-plumes. These sub-plumes are subsequently advected by Ekman transport. Data collection will consist of 4 seasonal surveys of Winyah Bay plume using ships (UNOLS ship requested), drones, Autonomous Surface Vehicles, and a floating platform to obtain profiles of water velocity, salinity, temperature, and turbulence properties. The sub-plume fronts shall be ubiquitous as long as the horizontal density gradient is prominent and the inertial period is greater than the tidal period. Observations will be complemented by numerical simulations with a non-hydrostatic numerical model. As Broader Impacts, the study will allow parametrization of cross-shelf plumes into lower resolution models that study land-ocean exchanges. The project will support 2 MS and 1 PhD students, and offer cruise opportunities to several undergraduate students. Data collected and their analysis will produce Ocean Data Analysis modules to be distributed to the oceanographic community. The project will be a collaboration between and R1 and a teaching institution.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.