Modelling Jets and Vortices in the Ocean

这一研究计划的目标是发展和改进海洋系统的理想化模型，并确定生物地球化学性质是如何在一些受观测约束的喷流和涡旋系统中传输的。不包括潮汐、喷流和涡旋是海洋中最具能量的特征，因此在物理和生物海洋性质的分布中起着至关重要的作用。利用最新开发的高性能计算软件，将对模式方程进行数值求解，以求解大范围的长度和时间尺度。这将有助于我们了解支配中尺度或附近的能量传递的物理机制。更具体地说，这项研究计划将回答一组基本问题，包括：1)哪些性质在决定射流和漩涡的稳定性方面至关重要？2)当不稳定性发展时，它们如何在非线性区域中演变，然后如何饱和以实现非线性平衡？3)作为不稳定过程的结果，能量如何在不同的长度和时间尺度之间级联？(4)这些非线性过程对物理和生物地球化学性质的传输，从而对生态系统的生命周期有什么影响？ 各种海洋模型被用来研究大尺度海洋流动。最普遍的可用于研究几乎所有大尺度海洋现象的模型是非静力原始方程(NH)模型。该模型的两个简化限制是多层浅水(SW)模型和准地转(QG)模型。我的研究小组将使用QG、SW和NH模型来理想化电流，并确定它们的稳定性特征和诱导输运。我们将与几位国际观测海洋学家合作完成这一任务。目前感兴趣的四个系统是布兰斯菲尔德洋流、阿曼湾洋流、南极坡面前锋和波弗特环流。我们对三维旋涡的研究将从理想化的旋涡结构开始，但也将使用来自地震反射技术的非常精细的尺度数据来观察介质。这项研究计划的一个补充方面是研究这些物理系统中的一些，这些系统要么耦合到简单的营养物-浮游植物-浮游动物模型，要么包含大小结构的模型。这将使我们能够确定生物有机体是如何从洋流和漩涡中运输和排放，并随后远距离运输的。

The objective of this research program is to develop and improve idealized models of oceanic systems and determine how biogeochemical properties are transported in a number of observationally-constrained systems of jets and vortices.  Excluding tides, jets and vortices are the most energetic features in the ocean and therefore play a crucial role in the distribution of physical and biological oceanic properties. Using recently-developed high performance computing software, the model equations will be solved numerically to resolve a wide range of length and time scales.  This will help us to understand the physical mechanisms that govern the energy transfers at or near the mesoscale. More specifically, this research program will answer a set of fundamental questions including: 1) Which properties are crucial in determining the stability of jets and vortices?  2) When instabilities develop, how do they evolve in the nonlinear regime and then saturate to achieve nonlinear equilibration?  3) As a result of the instability processes, how is energy cascaded between the various length and time scales?  4) What effect do these nonlinear processes have on the transport of physical and biogeochemical properties and therefore on the lifecycle of ecosystems? A variety of oceanic models are used to study large-scale oceanic flows.  The most general model that can be used to study virtually all large-scale oceanic phenomenon is the nonhydrostatic primitive equation (NH) model.  Two simplified limits of this model are the multi-layer Shallow Water (SW) and Quasi-Geostrophic (QG) models. My research group will use the QG, SW and NH models to idealize currents and determine their stability characteristics and induced transport. We will accomplish this in collaboration with several international observational oceanographers.  Four current systems of interest are the Bransifield Current, the Gulf of Oman Current, the Antarctic Slope Front  and the Beaufort Gyre. Our study of three-dimensional vortices will begin with idealized vortex structures but also observations of meddies using very fine scale data from seismic reflection techniques. A complimentary aspect of this research program is to investigate some of these physical systems coupled to either simple Nutrient-Phytoplankton-Zooplankton models or ones that contain size-structure.  This will enable us to determine how biological organisms are transported and emitted from currents and vortices and subsequently transported over great distances.