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Reader in Applied Mathematics



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BibTex format

author = {Berloff, P and Khatri, H},
doi = {10.1017/jfm.2019.579},
journal = {Journal of Fluid Mechanics},
pages = {939--961},
title = {Tilted, drifting jets over a zonally sloped topography: Effects of vanishing eddy viscosity},
url = {},
volume = {876},
year = {2019}

RIS format (EndNote, RefMan)

AB - Oceanic multiple jets are seen to possess spatiotemporal variability imposed by varyingbottom topography resulting in jets that can drift and merge. The dynamics of multiplejets over a topographic zonal slope is studied in a two-layer quasi-geostrophic model.The jets tilt from the zonal direction and drift meridionally. In addition to the tilted jets,other large-scale spatial patterns are observed, which are extracted using the principalcomponent analysis. The variances of these patterns are strongly influenced by the valuesof eddy viscosity and bottom friction parameters. The contribution of the tilted jets tothe full flow field decreases with decreasing friction and viscosity parameters, and purelyzonal large-scale modes, propagating in the meridional direction, populate the flow field.Linear stability analysis and two-dimensional kinetic-energy spectrum analysis suggestthat the zonal modes gain energy from ambient eddies as well as from the tilted jetsthrough nonlinear interactions. However, viscous dissipation and bottom friction tendto suppress the nonlinear interactions, which results in the inhibition of the upscaleenergy transfer from eddies to the zonal modes. These simulations suggest that, in thepresence of topography, alternating jet patterns may be sustained through interactionsamong various large-scale modes. This is different from the classical zonal jet formationarguments, in which direct eddy forcing maintains the jets.
AU - Berloff,P
AU - Khatri,H
DO - 10.1017/jfm.2019.579
EP - 961
PY - 2019///
SN - 0022-1120
SP - 939
TI - Tilted, drifting jets over a zonally sloped topography: Effects of vanishing eddy viscosity
T2 - Journal of Fluid Mechanics
UR -
UR -
UR -
VL - 876
ER -