Altmetric

A mechanism for jet drift over topography

File Description SizeFormat 
Jet_Drft.pdfAccepted version5.29 MBUnknownView/Open
Title: A mechanism for jet drift over topography
Authors: Khatri, H
Berloff, P
Item Type: Journal Article
Abstract: The dynamics of multiple alternating oceanic jets has been studied in the presence of a simple bottom topography with constant slope in the zonal direction. A baroclinic quasi-geostrophic model forced with a horizontally uniform and vertically sheared background flow generates mesoscale eddies and jets that are tilted from the zonal direction and drift with constant speed. The governing dynamical equations are rewritten in a tilted frame of reference moving with the jets, and the cross-jet time-mean profiles of the linear and nonlinear stress terms are analysed. Here, the linear stress terms are present because of the zonally asymmetric topography. It is demonstrated that the linear dynamics controls the drift mechanism. Also, it is found that the drifting jets are directly forced by the imposed vertical shear, whereas the eddies oppose the jets, although this is limited to continuously forced dissipative systems. This role of the eddies is opposite to the one in the classical baroclinic model of stationary, zonally symmetric multiple jets. This is expected to be more generic in the ocean, which is zonally asymmetric nearly everywhere.
Issue Date: 25-Jun-2018
Date of Acceptance: 1-Apr-2018
URI: http://hdl.handle.net/10044/1/61835
DOI: https://dx.doi.org/10.1017/jfm.2018.260
ISSN: 0022-1120
Publisher: Cambridge University Press (CUP)
Start Page: 392
End Page: 416
Journal / Book Title: Journal of Fluid Mechanics
Volume: 845
Copyright Statement: © 2018 Cambridge University Press. This paper has been accepted for publication and will appear in a revised form, subsequent to peer-review and/or editorial input by Cambridge University Press.
Sponsor/Funder: Natural Environment Research Council (NERC)
Funder's Grant Number: NE/R011567/1
Keywords: Science & Technology
Technology
Physical Sciences
Mechanics
Physics, Fluids & Plasmas
Physics
baroclinic flows
quasi-geostrophic flows
topographic effects
MULTIPLE ZONAL JETS
ANTARCTIC CIRCUMPOLAR CURRENT
SHALLOW-WATER TURBULENCE
BETA-PLANE TURBULENCE
SOUTHERN-OCEAN
BAROCLINIC INSTABILITY
GEOSTROPHIC TURBULENCE
JUPITERS ATMOSPHERE
SPECTRAL-ANALYSIS
BAROTROPIC MODEL
01 Mathematical Sciences
09 Engineering
Fluids & Plasmas
Publication Status: Published
Online Publication Date: 2018-04-26
Appears in Collections:Mathematics
Centre for Environmental Policy
Applied Mathematics and Mathematical Physics
Faculty of Natural Sciences



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Creative Commonsx