Do Submesoscales Affect the Large-Scale Structure of the Upper Ocean? ...

Submesoscale baroclinic instabilities have been shown to restratify the surface mixed layer and to seasonally energize submesoscale turbulence in the upper ocean. But do these instabilities also affect the large-scale circulation and stratification of the upper thermocline? This question is addresse...

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Bibliographic Details
Main Author: Menemenlis, Dimitris
Format: Dataset
Language:unknown
Published: Root 2023
Subjects:
Online Access:https://dx.doi.org/10.48577/jpl.nzb1r0
http://dataverse.jpl.nasa.gov/citation?persistentId=doi:10.48577/jpl.NZB1R0
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Summary:Submesoscale baroclinic instabilities have been shown to restratify the surface mixed layer and to seasonally energize submesoscale turbulence in the upper ocean. But do these instabilities also affect the large-scale circulation and stratification of the upper thermocline? This question is addressed for the North Atlantic subtropical mode water region with a series of numerical simulations at varying horizontal grid spacings (16, 8, 4, and 2 km). These simulations are realistically forced and integrated long enough for the thermocline to adjust to the presence or absence of submesoscales. Linear stability analysis indicates that a 2 km grid spacing is sufficient to resolve the most unstable mode of the wintertime mixed-layer instability. As the resolution is increased, spectral slopes of horizontal kinetic energy flatten and vertical velocities increase in magnitude, consistent with previous regional and short-time simulations. The equilibrium stratification of the thermocline changes drastically as the ...