气候变化领域集成服务门户(CCPortal): Submesoscale Phenomena Due to the Brazil Current Crossing of the Vitória-Trindade Ridge

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DOI	10.1029/2020JC016731
	Submesoscale Phenomena Due to the Brazil Current Crossing of the Vitória-Trindade Ridge
	Napolitano D.C.; da Silveira I.C.A.; Tandon A.; Calil P.H.R.
发表日期	2021
ISSN	21699275
卷号	126 期号:1
英文摘要	At 20.5°S, the Brazil Current and the Intermediate Western Boundary Current interact with a quasi-zonal seamount chain, the Vitória-Trindade Ridge (VTR). While the mesoscale variability generated due to these western boundary currents crossing the VTR has been recently studied, the submesoscale dynamics associated with such features have never been addressed. Here, we use new observations and a 2- km-resolution model to analyze the role of the VTR seamounts in the regional submesoscale dynamics, their seasonality, and instabilities. We present new high-resolution velocity and density observations that capture submesoscale features associated with the flow. Within these regions, potential vorticity (PV) reveals patches of symmetrically unstable flow close to seamounts. The horizontal resolution (Δx ≃ 1.5 km) of our quasi-synoptic observations (10 h) partially resolves submesoscale instabilities. Our Regional Oceanic Modeling System simulation identifies two regimes of submesoscale activity in the region, one typically associated with the seasonal cycle of the mixed layer, and a second associated with flow–topography interactions. A spatiotemporal analysis of the vertical buoyancy fluxes points to these flow–topography interactions as the main source of recurrent, deeper instabilities. As the VTR emerges as a submesoscale hotspot in the oligotrophic South Atlantic, the lack of observations still remains the main obstacle to better understand submesoscale processes in the region. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	Brazil Current; flow-topography interactions; instability; Intermediate Western Boundary Current; submesoscale; Vitória-Trindade Ridge
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186530
作者单位	Instituto Oceanográfico, Universidade de São Paulo, São Paulo, Brazil; Now at Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS), CNES-OMP-IRD-CNRS-UPS, Toulouse, France; Department of Mechanical Engineering, University of Masssachusetts Dartmouth, North Dartmouth, MA, United States; Institute of Coastal Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany
推荐引用方式 GB/T 7714	Napolitano D.C.,da Silveira I.C.A.,Tandon A.,et al. Submesoscale Phenomena Due to the Brazil Current Crossing of the Vitória-Trindade Ridge[J],2021,126(1).
APA	Napolitano D.C.,da Silveira I.C.A.,Tandon A.,&Calil P.H.R..(2021).Submesoscale Phenomena Due to the Brazil Current Crossing of the Vitória-Trindade Ridge.Journal of Geophysical Research: Oceans,126(1).
MLA	Napolitano D.C.,et al."Submesoscale Phenomena Due to the Brazil Current Crossing of the Vitória-Trindade Ridge".Journal of Geophysical Research: Oceans 126.1(2021).