CAREER: Evolution of Ocean Mesoscale Turbulence in a Changing Climate

职业：气候变化中海洋中尺度湍流的演变

• 批准号: 1553593
• 负责人: Ryan Abernathey
• 金额: $ 76.29万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-02-15 至 2022-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1553593&HistoricalAwards=false
• 关键词: CAREER; Evolution; Ocean; Mesoscale; Turbulence

Once the large-scale ocean circulation was viewed as a sluggish continuous flow. Thanks to new satellite and in situ observations, powerful numerical models, and advances in theory, it is now understood that ocean mesoscale turbulence, the highly energetic, nonlinear jumble of waves, eddies, and jets which characterizes ocean currents on scales of 20-500 km, is an essential component of ocean circulation, transport, and marine ecosystems. Because this turbulence draws its energy from instabilities of the large-scale flow, its properties are themselves sensitive to changes in climate. This project seeks to answer the question: how, and on what timescales, do large-scale changes in global climate affect the properties of ocean mesoscale turbulence? As such, the proposed work has the potential to transform how the climate community views mesoscale turbulence. Because most ocean climate models are too coarse to resolve the mesoscale, the effects of mesoscale turbulence are parameterized. As a result, mesoscale turbulence is reduced to a "parameter" to be tuned, rather than an emergent, dynamic part of the Earth system. The project is aimed at deepening basic physical understanding of the processes that regulate the properties of mesoscale turbulence and the timescales on which these properties respond to changes in climate. Consideration of this two-way interaction will lead to a richer understanding of the role of the ocean in the climate system, opening the door to new mechanisms for climate feedbacks. The project will also lead to methodological advances in Big Data computational tools for oceanography. The curriculum development will address the need for students to develop strong computational skills and, in particular, the capability to handle Big Data, to meet the emerging challenges of 21st century science. It will also promote active learning and the use of data in the oceanography classroom. The open-source nature of the teaching materials will encourage wide adoption. Strong interaction between research and education is guaranteed, because the same tools used in the research will be incorporated into the curriculum, both evolving together throughout the project.The research component of this CAREER award will examine the link between climate change, baroclinic instability, mesoscale eddy properties (kinetic energy and length scales), and mesoscale mixing, using a hierarchy of models and observations. Idealized process models will build a theoretical foundation of understanding of how changes in surface wind and buoyancy forcing lead to changes in mesoscale turbulence. Decadal variability in mesoscale statistics and baroclinic instability will also be examined in satellite and hydrographic observations. Finally, the theoretical framework and statistical analysis will be applied to global, eddy-resolving climate model simulations of greenhouse warming. To facilitate this work, Python-based computational tools for rapid data processing will be developed. These tools will be integrated into education through development of an open-source curriculum in "Big Data Oceanography," in which the computational skills necessary to study global, high-resolution datasets are taught side-by-side with core ocean science concepts. These modules will be deployed and assessed in an undergraduate course and disseminated widely online and at education conferences.

曾经大规模的海洋环流被看作是缓慢的连续流动。由于新的卫星和现场观测、强大的数值模式和理论的进步，现在人们了解到，海洋中尺度湍流是海洋环流、运输和海洋生态系统的一个重要组成部分，它是20-500公里尺度上的洋流的特征，是波浪、漩涡和喷流的高能量、非线性混乱。由于这种湍流从大尺度流的不稳定性中获取能量，其特性本身对气候变化很敏感。该项目旨在回答这样一个问题：全球气候的大规模变化如何以及在什么时间尺度上影响海洋中尺度湍流的特性？因此，提出的工作有可能改变气候界对中尺度湍流的看法。由于大多数海洋气候模式过于粗糙，无法解决中尺度问题，因此将中尺度湍流的影响参数化。因此，中尺度湍流被简化为一个有待调整的“参数”，而不是地球系统中一个新兴的、动态的部分。该项目旨在加深对调节中尺度湍流特性的过程和这些特性响应气候变化的时间尺度的基本物理理解。对这种双向相互作用的考虑将使人们对海洋在气候系统中的作用有更丰富的了解，为气候反馈的新机制打开大门。该项目还将推动海洋学大数据计算工具的方法论进步。课程开发将满足学生培养强大的计算技能的需求，特别是处理大数据的能力，以应对21世纪科学的新挑战。它还将促进海洋学课堂上的主动学习和数据的使用。教材的开源性质将鼓励广泛采用。研究和教育之间的密切互动得到了保证，因为研究中使用的相同工具将被纳入课程，两者在整个项目中一起发展。该职业奖的研究部分将使用模型和观测的层次来研究气候变化、斜压不稳定、中尺度涡特性（动能和长度尺度）和中尺度混合之间的联系。理想过程模型将为理解地面风和浮力强迫的变化如何导致中尺度湍流的变化奠定理论基础。还将在卫星和水文观测中研究中尺度统计的年代际变化和斜压不稳定性。最后，将理论框架和统计分析应用于全球涡旋气候模式模拟温室变暖。为了促进这项工作，将开发基于python的快速数据处理计算工具。这些工具将通过开发“大数据海洋学”的开源课程整合到教育中，在该课程中，研究全球高分辨率数据集所需的计算技能将与核心海洋科学概念并列教授。这些模块将在本科课程中部署和评估，并在网上和教育会议上广泛传播。

项目成果

Impacts of ice-shelf melting on water mass transformation in the Southern Ocean from E3SM simulations

E3SM 模拟显示冰架融化对南大洋水团转化的影响

• DOI: 10.1175/jcli-d-19-0683.1
• 发表时间: 2020
• 期刊: Journal of Climate
• 影响因子: 4.9
• 作者: Jeong, Hyein;Asay-Davis, Xylar S.;Turner, Adrian K.;Comeau, Darin S.;Price, Stephen F.;Abernathey, Ryan P.;Veneziani, Milena;Petersen, Mark R.;Hoffman, Matthew J.;Mazloff, Matthew R.
• 通讯作者: Mazloff, Matthew R.

Water mass transformation variability in the Weddell Sea in Ocean Reanalyses

海洋再分析中威德尔海的水团转化变化

• DOI: 10.5194/egusphere-2022-129
• 发表时间: 2022
• 期刊: Ocean science discussions
• 作者: Bailey, Shanice Tseng;Jones, Spencer;Abernathey, Ryan Patrick;Gordon, Arnold L.;Yuan, Xiaojun
• 通讯作者: Yuan, Xiaojun

Density-compensated overturning in the Labrador Sea

• DOI: 10.1038/s41561-019-0517-1
• 发表时间: 2020-01
• 期刊: Nature Geoscience
• 影响因子: 18.3
• 作者: Sijia Zou;M. Lozier;Feili Li;R. Abernathey;L. Jackson

Drivers of Local Ocean Heat Content Variability in ECCOv4

• DOI: 10.1175/jcli-d-20-0058.1
• 发表时间: 2020-02
• 期刊: Journal of Climate
• 影响因子: 4.9
• 作者: Jan‐Erik Tesdal;R. Abernathey