Kuroshio Transport: Inter-annual to Decadal Variability and the Underlying Mechanisms

黑潮输送：年际到十年间的变化及其潜在机制

• 批准号: 1028739
• 负责人: Magdalena Andres
• 金额: $ 54.2万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-10-01 至 2014-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1028739&HistoricalAwards=false
• 关键词: Kuroshio; Transport; Inter; annual; Decadal

Previous observational studies have highlighted a delay in Kuroshio transport variability relative to basin-scale atmospheric forcing, and thus have emphasized baroclinic Rossby wave adjustment as the mechanism by which remote forcing reaches the western boundary. However, recent observational studies and preliminary analyses suggest that, in fact, the Kuroshio and its extension each exhibit both delayed and immediate responses to the atmospheric forcing, suggesting that additional mechanisms play important roles in Kuroshio variability. The project will take a comprehensive look at these two response time scales, paying particular attention to the rapid response and to the connectivity of the components comprising the North Pacific subtropical gyre. The purpose of this study is to develop a better understanding of how the ocean responds to basin-scale wind forcing, especially in the western boundary currents and their extensions, with a focus on interannual to decadal variability in the Kuroshio system. In the North Pacific, such variability manifests itself in the Pacific Decadal Oscillation (PDO), a climate index reflecting the large-scale sea surface temperature variability, which is also well-correlated with the leading mode of wind stress curl variability over the most recent decades.A combination of existing observational data, idealized numerical model experiments, and output from an eddy-resolving ocean general circulation model (OGCM) will be used to accomplish three goals: (1) characterize the interannual to decadal variability in the Kuroshio in the East China Sea (ECS-Kuroshio), (2) investigate the relative roles of local versus remote atmospheric forcing on the barotropic and baroclinic oceanic responses in the ECS-Kuroshio and identify waveguide(s) by which remote forcing reaches the ECS-Kuroshio, and (3) relate the variability in the ECS-Kuroshio to variability in other parts of the subtropical gyre circulation, especially that in the Kuroshio Extension region.Intellectual Merit: The combined use of observations, a two-layer model, and ocean general circulation models output will lead to a more complete description of the Kuroshio system and a better understanding of the dynamics which give rise to variability in the western boundary current and its extension. Advancing the current understanding of the relationship between the inter-annual to decadal variability of ocean circulation and atmospheric forcing will be beneficial to the broader climate research community, particularly in the on-going community effort to improve inter-annual to decadal predictability.Broader Impacts: The first year of this project will partially support the postdoctoral training of the lead investigator, a junior scientist from an under-represented group. In addition, the lead investigator will perform outreach work with middle school students and their science teachers. This volunteer work will support the efforts of a school in Rhode Island to implement a 2009 Science and Math Scholars (SAMS) grant by NASA to improve the quality of science and math education in middle schools.

先前的观察性研究强调了与盆地规模的大气强迫相对于盆地规模的大气强迫的延迟，因此强调了斜压rossby波调节，这是远程强迫到达西部边界的机制。然而，最近的观察性研究和初步分析表明，实际上，黑子及其扩展对大气强迫表现出延迟和直接响应，这表明其他机制在黑鲁西奥变异性中起着重要作用。该项目将全面了解这两个响应时间尺度，特别注意快速响应以及包括北太平洋亚热带Gyre组成的组件的连通性。这项研究的目的是更好地了解海洋如何应对盆地尺度的风力强迫，尤其是在西部边界电流及其扩展中，重点是对黑素系统的年际变化。在北太平洋中，这种可变性在太平洋十年际振荡（PDO）中表现出来，这是一种气候指数，反映了大规模的海面温度可变性，这也与最新的风力应力变化模式相关数十年。现有观察数据，理想化的数值模型实验以及涡流分辨率海洋通用循环模型（OGCM）的输出的组合将用于实现三个目标：（1）表征在黑杂的际变异性中，在黑元中的际变异性表征东中国海（ECS-KUROSHIO），（2）研究局部强迫在ECS-KUROSHIO中局部与远程大气强迫的相对作用，并识别远程强迫到达ECS-KUROSHIO，ECS-KUROSHIO，ECS-KUROSHIO， （3）将ECS-KuroShio的可变性与亚热带回旋循环的其他部分的变异性联系起来，尤其是在黑鲁希奥扩展区域中的可变性。智能优点：观测值的综合使用，两层模型和海洋一般循环模型的输出将导致对黑鲁希奥系统的更完整描述，并更好地理解动态，从而导致西部边界电流及其扩展的变化。促进对海洋循环和大气强迫的年度与十年变化之间的关系的当前理解将对更广泛的气候研究界有益，尤其是在不断的社区努力中，以改善年间可预测性。 ：该项目的第一年将部分支持主要研究人员的初级科学家的主要研究人员的博士后培训。此外，首席调查员将与中学生及其科学老师一起进行外展工作。这项志愿者工作将支持罗德岛州一所学校的努力，以实施NASA 2009年的科学和数学学者（SAMS）赠款，以提高中学的科学和数学教育质量。