Collaborative Research: Nonlinear Wake Observations at a Kuroshio Seamount (NOKS)

合作研究：黑潮海山非线性尾流观测 (NOKS)

• 批准号: 2318951
• 负责人: Anda Vladoiu
• 金额: $ 38.3万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2318951&HistoricalAwards=false
• 关键词: Collaborative; Research; Nonlinear; Wake; Observations

Oceanographic data collected in the lee of Hirase Seamount in Tokara Strait, south of Japan, during 2021-2022 will be analyzed to investigate strong nonlinear Kuroshio-seamount interactions and associated turbulence. The data include highly resolved observations of temperature, salinity, velocity, and turbulent dissipation measured from ship, moorings, and profiling float arrays. The data will be used to identify the dominant nonlinear terms in the momentum and buoyancy equations, quantify potential vorticity anomalies, and determine the vertical and lateral instability mechanisms responsible for energetic turbulence layers extending 20 km downstream of the seamount. Elucidating turbulence generation mechanisms, especially in nonlinear wakes, is an essential task to improve existing turbulent dissipation and mixing parameterizations, and therefore has broad implication for the energy cascade, mass and nutrient transports, and biogeochemical budgets in simulations and the ocean. This project will provide support for early-career scientist Dr. Anda Vladoiu. All APL-UW PIs are actively engaged in outreach at UW and local science centers and Seattle K-12 classrooms. Lien also actively supports the summer program for UW undergraduate students. Kunze is a Science Communication Fellow at the Pacific Science Center in Seattle, which involves four volunteer Science Spotlight activities per year, and participation in the annual Pacific Science Center-Climate Curiosity Weekend, to introduce the general public to the meridional overturning circulation and ocean turbulent mixing.Strong interactions between the Kuroshio and Hirase Seamount produce a uniquely nonlinear and turbulent regime that allows study outside the usual linear internal-wave and balanced dynamics. Four-dimensional fine- and microstructure surveys will be analyzed to investigate strong nonlinear Kuroshio-seamount interactions and associated turbulence where Rossby numbers exceed 1 and gradient Froude numbers are 𝑂(1). Shipboard ADCP, underway CTD and underway VMP radiator surveys, as well as four full-depth EM-APEX float box-arrays, provide horizontal submesoscale (~ 1 km) and vertical finescale (~ 10 m) flow structures. Two ADCP/CTD moorings provide 6-month time-series of the background flow variability and shear- unstable layers. These data will be used to (i) identify the dominant nonlinear terms in the momentum and buoyancy equations, (ii) quantify potential vorticity (PV) anomalies and (iii) determine the vertical and lateral instability mechanisms responsible for energetic turbulence layers with diapycnal diffusivities 𝐾 ∼ 10−2 m2 s−1 extending 20 km downstream of the seamount. The six-month long mooring time-series in the lee of the seamount will allow the separation of subinertial and internal-wave fluctuations to resolve possible time-space aliasing. These will generally improve understanding of nonlinear flow-topography interactions in the ocean.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

将在2021 - 2022年期间在日本南部的托卡拉海峡的Hirase Seamount的Lee收集的海洋数据进行分析，以研究强大的非线性黑杂质 - kuroshio-Seamount相互作用和相关的湍流。数据包括高度分辨的温度，盐度，速度和湍流耗散的观察结果，这些耗散是通过船舶，系泊和分析浮点阵列测得的。数据将用于在动量和浮力方程中识别主要的非线性项，量化潜在的涡度异常，并确定负责能量湍流层的垂直和横向不稳定性机制，该机制延伸了延伸延伸20 km。阐明湍流产生机制，尤其是在非线性唤醒中，是改善现有的湍流耗散和混合参数的重要任务，因此对能源级联，质量和营养运输以及模拟和海洋中的生物地球化学预算具有广泛的影响。该项目将为早期的科学家Anda Vladoiu博士提供支持。所有APL-UW PI都在西澳大学，当地科学中心和西雅图K-12教室中积极参与外展。留置权还积极支持UW本科生的夏季计划。 Kunze是西雅图太平洋科学中心的一名科学传播研究员，涉及每年四次志愿科学聚焦活动，并参加年度太平洋科学中心气候好奇心周末，将公众介绍给子午线推翻圈子和海洋动荡的混合。黑鲁西奥和Hirase海山之间的强烈相互作用产生了独特的非线性和湍流制度，允许在通常的线性内波和平衡动力学之外进行研究。将分析四维精细和微观结构调查，以研究强烈的非线性黑杂质 - seamount相互作用以及相关的湍流，其中rossby数量超过1，而梯度弗洛德数字为𝑂（1）。船上ADCP，CTD和正在进行的VMP散热器调查以及四个全深度EM-APEX浮点盒阵列，提供水平尺度尺度（〜1 km）和垂直罚款（〜10 m）流量结构。两个ADCP/CTD系泊设备提供了背景流变性和剪切不稳定层的6个月时间序列。 These data will be used to (i) identify the dominant nonlinear terms in the momentum and buoyancy equations, (ii) quantify potential vorticity (PV) anomalies and (iii) determine the vertical and lateral instability mechanisms responsible for energy turbulence layers with diapycnal diffusivities 𝐾 ∼ 10-2 m2 s-1 extending 20 km downstream of the seamount.海底李的六个月长的系泊时间序列将允许分离亚允许和内波波动，以解决可能的时空混叠。这些通常将提高对海洋中非线性流程图相互作用的理解。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，被认为是通过评估而被视为珍贵的。