NSF-OCE: Modeling and Assimilation of Internal Tides in Interaction with Subinertial Wind-Forced Flows in the Coastal Ocean

潮汐引起的内部运动在沿海环境中很重要，因为它们增强了该地区洋流的时空变化、混合和生物生产力。潮汐与其他动力过程相互作用，可导致间歇性的内部潮汐。传统的观测在空间和时间上过于稀疏，无法解决这些过程，因此有关它们的基本问题仍未得到解答。在这项研究中，俄勒冈州立大学的海洋学家计划解决一些问题，比如这些内部潮汐是否对海洋表面、内部和底部的陆架运输有重大贡献，以及这些运输如何与风的运动相比较。此外，他们将探讨这些潮汐如何促进水平分散和垂直混合，以及这些过程如何受到分层变化和风驱动流的影响。他们的目标是确定大陆架环境中内部潮汐的可预测性，并具体应用俄勒冈大陆架夏季上升流的情况。区域海洋模拟系统（ROMS）将与高频雷达以及最近其他NSF项目（如COAST和GLOBEC）的系泊观测一起使用。新的建模和分析技术将被实施，包括使用切线和伴随模型的变分数据同化方法和数据分析和综合的方法。这些结果将有助于确定俄勒冈海岸内部潮汐加剧的区域，这可能指导未来观测计划的设计和发展。这项研究将产生广泛的影响，因为它将为化学和生物海洋学家提供一个改进的数值模型，并将协助发展一个海岸预报系统，以满足公众在污染运输、搜索和救援任务、渔业、娱乐和教育方面的广泛需要。研究生将接受建模和数据同化方法方面的培训。

OCE-0648314Tidally induced internal motions are important in the coastal environment because they enhance the spatial and temporal variability of currents, mixing and biological productivity in the region. Tides interact with other dynamical processes which can result in an intermittent internal tide. Traditional observations are too sparse in space and time to resolve these processes and thus fundamental questions about them remain unanswered. In this study, oceanographers at Oregon State University plan to address questions such as whether these internal tides contribute significantly to shelf transports on the surface, interior and bottom of the ocean and how these transports compare to the wind-forced motions. In addition they will address how these tides contribute to horizontal dispersion and vertical mixing and how these processes are affected by changes in stratification and the wind-driven currents. Their goal is to determine the predictability of internal tides in the shelf environment with a specific application of the summer upwelling regime on the Oregon Shelf. The Regional Ocean Modeling System (ROMS) will be used with observations from High Frequency radars as well as moorings from recent other NSF programs such as COAST and GLOBEC. New modeling and analysis techniques will be implemented included variational data assimilation methods using the tangent linear and adjoint models and methodologies for data analysis and synthesis. The results will assist in identifying areas of intensified internal tides along the Oregon coast, which may guide the design and development of future observational programs. The study will have a broad impact because it will provide an improved numerical model for chemical and biological oceanographers and will also assist in the development of a coastal forecasting system that can serve broad public needs regarding pollution transport, search and rescue missions, fisheries, recreation and education. A graduate student will be trained in modeling and data assiilation methods.