Collaborative Research: Observations of the Structure and Dynamics of Mid-Shelf Fronts

一个现场计划，包括遥感，船上，系泊，和自主车辆测量，建议获得基本的观测数据的结构和变化的前在大西洋中部海湾。虽然在SST中检测到，从动力学的角度来看，这一功能是一个盐度锋，分离冷，低盐度的内陆架水温暖，咸外陆架水。该锋面的垂直结构知之甚少，其形成机制也未得到描述，该项目的目标是检验两种相互竞争的理论，以形成中陆架锋面，确定锋面的垂直结构和变异性，并评估锋面是否作为溶解物质和颗粒物质跨陆架交换的障碍。卫星SST，高频雷达表面电流，和自主滑翔机部分的同时观测将进行分析，以确定表面速度喷流，如果存在，表面热锋，和地下水文结构之间的关系。将使用一个拖曳式起伏航行器来获得水文和速度的多个高分辨率横锋面剖面，以阐明锋面结构如何在潮汐和潮下带时间尺度上变化。对短寿命镭同位素活动的测量将用于推断跨大陆架混合速率。在3个月期间对速度和水文剖面进行停泊观测，将能够估计跨大陆架浮力通量及其发散，提高我们对沿海海洋中普遍存在的大陆架中部锋的认识，将有助于确定沿海海洋在碳循环中的作用这一更广泛的科学目标。这也是研究幼鱼和幼鱼的研究人员感兴趣的，因为它可能会影响产卵区和育苗区相距甚远的生物体（如蓝鱼）的招募。计划与URI海洋项目办公室合作，开展外展工作，让K-12教师接触海洋海洋学。将通过向教育工作者提供数据，与大西洋中部海洋科学教育卓越中心建立伙伴关系。描述海洋前沿的影响和生成的课程将被添加到已经张贴在COOLClassroom [http://www.coolclassroom.org]上的现有项目中。该项目将为本科生提供研究机会，并将包括培训一名研究生。

A field program including remotely sensed, shipboard, moored, and autonomous vehicle measurements is proposed to obtain basic observational data on the structure and variability of the front in the mid-Atlantic Bight. Although detected in SST, from a dynamical perspective this feature is a salinity front that separates cool, lower salinity inner shelf water from warm, saltier outer shelf water. The vertical structure of this front is poorly known and the mechanism of formation has not been described.The objectives of the project are to test two competing theories for the formation of the mid-shelf front, determine the vertical structure and variability of the front, and to evaluate whether the front acts as a barrier to cross-shelf exchange of dissolved and particulate materials. Concurrent observations of satellite SST, HF radar surface currents, and autonomous glider sections will be analyzed to determine the relationship between the surface velocity jet, if present, the surface thermal front, and the subsurface hydrographic structure. A towed undulating vehicle will be used to obtain multiple high-resolution cross-frontal sections of hydrography and velocity to elucidate how the frontal structure varies on tidal and subtidal time scales. Measurements of the activities of short-lived radium isotopes will be used to infer crossshelf mixing rates. Moored observations of velocity and hydrographic profiles over a 3-month period will allow estimation of the cross-shelf buoyancy flux and its divergence.Improving our understanding of mid-shelf fronts, which are ubiquitous in the coastal ocean, will contribute to the broader scientific thrust of determining the role of the coastal ocean in the carbon cycle. It is also of interest to researchers studying larval and juvenile fish, as it likely impacts recruitment of organisms with widely separated spawning and nursery areas (such as bluefish).Collaboration is planned with the URI Office of Marine Programs in their outreach efforts to give K-12 teachers exposure to sea-going oceanographic. A partnership with the Mid-Atlantic Center for Ocean Science Education Excellence will be developed by making data available to educators. Curricula describing the impact and generation of ocean fronts will be added to existing projects already posted on the COOLClassroom [http://www.coolclassroom.org]. The project will provide research opportunities for undergraduate students and will include the training of a graduate student.