Collaborative Research: Effects of Eddies and Waves on the Westward Transport off Central California

这项研究的重点是了解中尺度变率和Rossby波在加州洋流系统(CCS)动能、热量、盐分和示踪物向西[称为西向输送(WT)]近海传播中的作用。利用现场观测、遥感观测和数值模拟方法，对加州中部近海CCS的中尺度涡旋变率进行了数值预报，并对相关的WT进行了量化。目标是了解涡旋、急流和波浪以及它们的相互作用如何影响WT，并确定对这一过程负责的尺度。还将以足够简化的形式制定WT的参数化方案，以便从稀疏观测中进行验证，并允许生物和气候应用。虽然研究的每个组成部分都有自己独立的目标，但各组成部分以协同的方式结合在一起，根据模型结果和数据的融合产生所需的即播产品。通过与全球SODA嵌套的区域ROMS层次(UCLA)进行的模式集成将被用作在中尺度和次中尺度上构建感兴趣区域的可靠三维动力学的指导。将使用卫星数据(SST、测高和颜色)、漂浮物(WOCE)和次表层(ARGO和RAFOS)浮标观测数据以及水文(CTD/VMADCP)数据提供独立于模型的CCS物理描述，并作为独立模型验证的基础。ROMS通过面向特征的方法进行验证，使用多个指标来找到可接受的模型配置，以便以最准确的方式再现沿海岸和跨海岸的运输。通过对模型结果和数据进行相关性和尺度分析，对小波变换特征进行修正和更新。该项目将有助于理解副热带东边界上升流系统中涡旋和波浪引起的西向输送以及气候时间尺度上的跨斜率交换。涡旋和波浪在质量和动量输送中起主要作用，从而影响中尺度流动中的输送、阻力和耗散。由于它们的生命周期很长，涡流和波浪重新分配了上升到边缘附近的冷水，这也可能影响到上面的大气，从而通过影响天气和气候的海气相互作用来影响。向西输送与常规扩散的显著偏离需要寻找考虑长时滞相关效应的新类型的热量和盐分输送的参数化方案。该提案在电报传输模式的背景下建议和发展了这样的参数化，这可能有助于预报加利福尼亚州中部海岸的生物生产力和海洋模式的气候应用。为分析高分辨率海洋模式和观测的输出场，开发了一套用于图像分析、相干涡波识别和分类、数据融合、拉格朗日分析和模式数据比较的数学工具。该项目将涉及研究生和博士后，其中包括来自海军研究生院(加利福尼亚州蒙特利)以及蒙特利地区其他机构的女性。研究成果将转化为海军研究生院和MLML研究生和本科课程的教具。这些教材还将用于研究生级别的海洋科学教科书。还将对最先进的海洋科学调查作出贡献。结果应与生物生产力、渔业、石油和天然气回收作业和航海有关。活动将包括向公众、政策制定者、私营公司和地方政府官员公开交流和介绍。

The study focuses on understanding the role of mesoscale variability and Rossby waves in the offshore propagation of kinetic energy, heat, salt and tracers to the west [referred as westward transport (WT)] in the California Current System (CCS). In-situ observations, remote-sensed observations, and numerical modeling are used to nowcast meso-scale eddy variability in the CCS off Central California and to quantify associated WT. The goal is to understand how eddies, jets and waves as well as their interactions affect WT and to determine the scales responsible for this process. Parameterization schemes for WT will also be developed in a form sufficiently simplified to be verified from sparse observations and to permit biological and climate applications. While each component of the study has its own stand-alone objectives, components are combined in a synergistic way to produce the desired nowcast product based on fusion of model results and data. Model integrations through a hierarchy of regional ROMS (UCLA) nested with a global SODA will be used as guidance in constructing reliable three-dimensional dynamics of the region of interest on mesoscale and sub-mesoscale. Satellite data (SST, altimetry and color), drifter (WOCE) and subsurface (Argo and RAFOS) float observations, and hydrographic (CTD/VMADCP) data will be used to provide a physical description of the CCS independent of the model and as a basis for independent model validation. The ROMS is validated through the feature-oriented approach using multiple metrics to find an accepted model configuration for reproduction of along- and across-shore transport in the most accurate manner. WT characteristics are revised and updated through correlation and scaling analyses applied to model results and data. The project will contribute to understanding the westward transport induced by eddies and waves in a subtropical eastern-boundary upwelling system as well as the across slope exchange on climate time scales. Eddies and waves play a major role in the transport of mass and momentum, thus affecting transport, drag, and dissipation in mesoscale flows. Due to their long lifetimes, eddies and waves redistribute the cold water upwelled near the margin that may also affect the overlying atmosphere and hence through air-sea interactions impacting both weather and climate. A significant deviation of the westward transport from conventional diffusion necessitates search for new types of parameterizations for heat and salt transport accounting for long time lag correlation effects. The proposal suggests and develops such a parameterization in context of the telegraph transport model, which may be useful for forecasting biological productivity along the Central California coast and in climate applications of oceanic models. A set of mathematical tools for image analysis, for identification and classification of coherent eddies and waves, data merging, Lagrangian analysis and model-data comparison is developed for the analysis of output fields of high-resolution oceanic models and observations. The project will involve graduate students and post-docs including women from the Naval Postgraduate School (Monterey, CA) as well as other Monterey area institutions. Research results will be converted into teaching aids for graduate and undergraduate courses at the Naval Postgraduate School and MLML. These educational materials will also be used for a graduate-level marine science textbook. Contributions will also be made to state-of-the-art surveys of marine sciences. Results should have relevance for biological productivity, fisheries, oil and gas recovery operations and navigation. Activities will include open communications and presentations to the public, policy-makers, private companies and local government officials.