Ocean convection and mixing: from signature to parameterization

海洋对流和混合：从签名到参数化

• 批准号: RGPIN-2018-03740
• 负责人: Kelley, Daniel
• 金额: $ 3.64万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=761595
• 关键词: Ocean; convection; mixing; signature; parameterization

I request support for continuing research on the dynamics of ocean mixing and watermass exchange. My main interest is in key phenomena that cannot be handled directly by numerical models, owing to coarse model resolution. Dynamically-based parameterizations of such phenomena are needed for reliable numerical simulation of the ocean and climate system.Over the funding period, my research program will build on two themes of great scientific interest and practical importance, one related to ice in the Northwest Passage and the other to watermass interactions on the Scotian Shelf. The work will be carried out with students, and the planned close collaboration with partners in Department of Fisheries and Oceans should contribute greatly to the career potential of the graduates.Theme 1: convective heat fluxes in ice-influenced domainsMy research group will study the effects of ocean turbulence and convection on ice cover in coastal waters, using fine-scale signatures acquired with an advanced profiling instrument deployed in Barrow Strait. This is in the Northwest Passage, so a key initial objective will be to improve on statistical predictions of the periods of ice cover, a prime factor for navigation. By incorporating signatures throughout the water column, the methodology will improve upon previous predictions using point-wise measurements. However, the improvement involves more than mere statistical power. We will also apply results from the turbulence literature to infer heat fluxes, and results from the convection literature to infer ice transformation. Another objective is to relate these things to the background state, to develop more robust predictions of ice cover in the study region. This work will pave the way to improved parameterizations for use in models of general ice-affected regions.Theme 2: inference of lateral interleaving with glider-based instrumentationOcean gliders are used increasingly to observe coastal waters. Their zigzag profiling motion yields high spatial sampling densities that reveal ocean variations that are difficult to resolve with conventional ship-based surveys. We will take advantage of this enhanced resolution to examine fine-scale frontal features on the Scotian Shelf, with a particular focus on cross-frontal exchanges caused by quasi-lateral interleaving. My tests with glider surveys carried out over the past few years suggest the feasibility of tracking interleaving motions and associated hydrographic changes in sufficient detail to provide improved dynamical constraints on parameterizations of cross-frontal exchange. The results will deepen understanding of important issues relating to how the waters of the Nova Scotia current interact with waters derived from the Gulf Stream. The anticipated advances in sampling and analysis methodologies will also benefit studies of the many other coastal regions in which watermasses collide.

我请求支持继续研究海洋混合和水团交换的动力学。我的主要兴趣是在关键的现象，不能直接处理的数值模型，由于粗糙的模型分辨率。这种现象的动力学参数化需要可靠的数值模拟的海洋和气候system.Over的资助期间，我的研究计划将建立在两个主题的巨大的科学兴趣和实际意义，一个有关冰在西北航道和其他水团的相互作用在斯科舍架。这项工作将与学生一起进行，计划与渔业和海洋部的合作伙伴密切合作，这将大大有助于毕业生的职业潜力。冰影响区域的对流热通量我的研究小组将研究海洋湍流和对流对沿海沃茨冰盖的影响，利用部署在巴罗海峡的先进剖面仪获得的精细尺度特征。这是在西北航道，所以一个关键的初始目标将是改善对冰盖时期的统计预测，这是航行的主要因素。通过在整个水柱中加入签名，该方法将改进以前使用逐点测量的预测。然而，这种改进不仅仅涉及统计功效。我们还将应用湍流文献的结果来推断热通量，对流文献的结果来推断冰的转化。另一个目标是将这些东西与背景状态联系起来，以便对研究区域的冰盖进行更可靠的预测。这项工作将铺平道路，以改善参数化模型中使用的一般冰影响regions.Theme 2：推断横向交错与滑翔机为基础的instrumentationOcean滑翔机越来越多地用于观察沿海沃茨。它们的锯齿形剖面运动产生了高空间采样密度，揭示了传统船基调查难以解决的海洋变化。我们将利用这一增强的分辨率来研究精细尺度的锋面特征的斯科舍架，特别侧重于跨锋面交流所造成的准横向交错。我的测试与滑翔机调查在过去几年中进行的建议的可行性跟踪交错运动和相关的水文变化的足够详细的参数化的跨锋面交换提供改进的动力学约束。研究结果将加深对新斯科舍省洋流沃茨如何与墨西哥湾流沃茨相互作用的重要问题的理解。在取样和分析方法方面的预期进展也将有益于对水团发生碰撞的许多其他沿海地区的研究。