Exploring extreme vertical currents in the Western Mediterranean Sea

该项目的目标是探索连接海洋表面和底部与内部的运动，即所谓的“亚中尺度海流”，它影响海洋地球化学性质的变化。这些运动在水平方向上跨越数百到数千米，在垂直方向上跨越数十到数百米，并且它们在几个小时到几天内变化。在这个项目中调查的方面是运动的空间结构，它们的动态，以及它们相关的垂直速度如何连接表层和底层与海洋的内部。这次探索将结合多个计算机模拟，重点放在地中海盆地最西部的阿尔沃兰海。这项研究将扩展研究人员自己的结果，仔细检查该地区的次中尺度运动。这些结果表明，垂直输送发生在表面锋（不同性质的水团之间的边界）附近和地形障碍物附近的底部。本计画将在前人研究成果的基础上，进一步探讨次中尺度运动的演化。这项研究是基于这样的假设，根据以往的结果，在研究区域的最大垂直速度相关联的表面锋和相互作用的电流与底部地形。这项研究的结果应有助于更好地了解海洋中物质的垂直运输。该项目将为西班牙博士生提供访问加州大学洛杉矶分校的机会，并获得计算流体动力学，数据分析和科学交流方面的经验。该项目还将涉及高中学生的外联活动，其目标是探讨中尺度以下海流在促进连接表层和底层与海洋内部的垂直海流方面的作用。这项研究将以地中海西部盆地阿尔沃兰海的数值模拟为基础。这项工作建立在最近的，现实的，高分辨率的数值模式研究的PI，分析在这一地区的次中尺度流。这些结果表明，快速和深层垂直位移与表面锋以及海流与水深的相互作用有关。PI将通过一系列逼真的嵌套模型实验进行广泛的数值模拟，这些实验的时间和空间分辨率不断提高，并结合理想化的过程研究模拟和拉格朗日方法。这种结合现实的过程策略将描述自发出现和随后的演变亚中尺度流。该项目将促进对引发海洋垂直流的机制的理解，这些机制具有相关的物理和地球化学影响。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The goal of this project is to explore motions that connect the surface and the bottom of the ocean with the interior, the so-called ‘submesoscale currents’, which influence the variability of biogeochemical properties in the ocean. These motions span between hundreds and thousands of meters in the horizontal, between tens and hundreds of meters in the vertical, and they vary over several hours to days. Aspects investigated in this project are the spatial structure of the motions, their dynamics, and how their associated vertical velocities connect the surface and bottom layers with the ocean’s interior. The exploration will be done combining multiple computer simulations focused in the Alboran Sea, the westernmost region of the Mediterranean basin. The study will extend the investigators’ own results that scrutinized submesoscale motions in this region. Those results illustrated that vertical transports occur near surface fronts (the boundary between water masses of different properties) and at the bottom near topographic obstacles. This project intends to expand on the previous results by scrutinizing the evolution of submesoscale motions. The study is based on the hypothesis, based on previous results, that the largest vertical velocities in the study area are associated to surface fronts and to interactions of the currents with bottom topography. Results from this study should contribute to better understanding of the vertical transport of materials in the ocean. The project will provide opportunities for Spanish PhD students to visit UCLA and acquire experiences in computational fluid dynamics, data analysis, and scientific communication. It will also involve high-school student outreach activities.The goal of this project is to explore the role of submesoscale currents in promoting vertical currents that connect the surface and bottom layers with the ocean interior. The study will be based on numerical simulations of the Alboran Sea, in the western Mediterranean basin. The work builds on a recent, realistic, high-resolution numerical model study by the PIs that analyzes submesoscale flows in this region. Those results illustrate that rapid and deep vertical displacements are associated with surface fronts and with interactions of the currents with bathymetry. The PIs will conduct extensive numerical simulations with a series of realistic, nested-model experiments at increasing time and spatial resolutions, in combination with idealized process-study simulations and Lagrangian approaches. This combination of realistic-process strategy will describe the spontaneous emergence and subsequent evolution of submesoscale currents. The project will advance understanding of the mechanisms that trigger vertical currents in the ocean, which have relevant physical and biogeochemical implications.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.