Water Mass Transformation and Downwelling around Islands

岛屿在动力学上是有趣的，因为它们对岛架和公海之间的交换构成了强有力的动力学约束，并且可以导致重要的水团转换和输出。这些动力学也影响了陆架、陆坡和远离岛屿的环流。理想化和现实的数值海洋模型将与简单的分析模型相结合，以更好地了解是什么控制着岛屿周围的水团转化和净下降流。 这里强调的理想化框架将使人们更清楚地了解为什么这些过程在不同岛屿之间存在差异，以及它们在气候变化中如何变化。 这项赠款支持的工作将有助于在伍兹霍尔海洋研究所的本科生和研究生教育计划。分析模型和涡解数值模型的组合将提供深入了解的动力学和热力学控制的diapycnal质量通量和混合的岛屿架和出口产品沃茨到周围的海洋。将特别关注不对称强迫的情况下，浮力强迫，风应力，周围的海洋，或底部地形变化周围的岛屿周长。一般的方法将使用理论来识别相关的无量纲数，并提供一个动力学框架，以指导和解释数值模型计算。数值模型将用于测试理论的基本预测，同时更全面地解决重要的过程，如非线性涡流通量和对流。感兴趣的内容包括：产水团的性质;上升流和下降流的分布;净贯流质量通量;诱导环流和陆架坡折带通量。

Islands are dynamically interesting because they pose strong dynamical constraints on the exchange between the island shelf and the open ocean, and can result in important water mass transformation and export. These dynamics also influence the circulation on the shelf, on the slope, and far from the island. Idealized and realistic numerical ocean models will be combined with simple analytic models to better understand what controls water mass transformation and net downwelling around islands. The idealized framework emphasized here will provide a clearer understanding of why these processes differ between different islands and how they might be expected to change in a changing climate. Work supported by this grant will contribute to both undergraduate and graduate education programs at the Woods Hole Oceanographic Institution.The combination of analytic models and eddy resolving numerical models will provide insights into the dynamics and thermodynamics that control the diapycnal mass flux and mixing on island shelves and export of product waters to the surrounding ocean. Particular focus will be given to asymmetrical forcing situations in which the buoyancy-forcing, wind stress, surrounding ocean, or bottom topography vary around the island perimeter. The general approach will use theory to identify the relevant non-dimensional numbers and provide a dynamical framework with which to guide and interpret the numerical model calculations. The numerical models will be used to test the basic predictions from the theory while more completely resolving important processes such as nonlinear eddy fluxes and convection. Quantities of interest include: properties of product water masses; distribution of upwelling and downwelling; net diapycnal mass flux; induced circulations and fluxes across the shelf break.