Spatiotemporal Characteristics of the Near-Surface Turbulent Cascade at the Submesoscale in the Drake Passage

Author:

Tedesco P. F.1ORCID,Baker L. E.2,Naveira Garabato A. C.3,Mazloff M. R.4,Gille S. T.4,Caulfield C. P.5,Mashayek A.1

Affiliation:

1. a Department of Earth Sciences, University of Cambridge, Cambridge, United Kingdom

2. b School of Mathematics, University of Edinburgh, Edinburgh, United Kingdom

3. c Ocean and Earth Science, University of Southampton, Southampton, United Kingdom

4. d Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California

5. e Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, United Kingdom

Abstract

Abstract Submesoscale currents and internal gravity waves achieve an intense turbulent cascade near the ocean surface [depth of 0–O(100) m], which is thought to give rise to significant energy sources and sinks for mesoscale eddies. Here, we characterize the contributions of nonwave currents (NWCs; including eddies and fronts) and internal gravity waves (IGWs; including near-inertial motions, lee waves, and the internal wave continuum) to near-surface submesoscale turbulence in the Drake Passage. Using a numerical simulation, we combine Lagrangian filtering and a Helmholtz decomposition to identify NWCs and IGWs and to characterize their dynamics (rotational versus divergent). We show that NWCs and IGWs contribute in different proportions to the inverse and forward turbulent kinetic energy cascades, based on their dynamics and spatiotemporal scales. Purely rotational NWCs cause most of the inverse cascade, while coupled rotational–divergent components of NWCs and coupled NWC–IGWs cause the forward cascade. The cascade changes direction at a spatial scale at which motions become increasingly divergent. However, the forward cascade is ultimately limited by the motions’ spatiotemporal scales. The bulk of the forward cascade (80%–95%) is caused by NWCs and IGWs of small spatiotemporal scales (L < 10 km; T < 6 h), which are primarily rotational: submesoscale eddies, fronts, and the internal wave continuum. These motions also cause a significant part of the inverse cascade (30%). Our results highlight the requirement for high spatiotemporal resolutions to diagnose the properties and large-scale impacts of near-surface submesoscale turbulence accurately, with significant implications for ocean energy cycle study strategies.

Funder

Office of Naval Research Global

Natural Environment Research Council

Centre for Doctoral Training in Mathematics of Planet Earth

NASA Surface Water and Ocean Topography

National Science Foundation

NASA Ocean Surface Topography Science Team

Southern Ocean Carbon and Heat Impact on Climate

Publisher

American Meteorological Society

Subject

Oceanography

Reference109 articles.

1. Diagnosing cross-scale kinetic energy exchanges from two submesoscale permitting ocean models;Ajayi, A.,2021

2. Observations of near-inertial internal gravity waves radiating from a frontal jet;Alford, M. H.,2013

3. Near-inertial internal gravity waves in the ocean;Alford, M. H.,2016

4. Mapping the energy cascade in the North Atlantic Ocean: The coarse-graining approach;Aluie, H.,2018

5. Near-surface oceanic kinetic energy distributions from drifter observations and numerical models;Arbic, B. K.,2022

Cited by 2 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3