On modeling turbulent exchange in buoyancy-driven fronts

Gustavo M. Marques, Tamay M Ozgokmen

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Our primary objective is to quantify the uncertainty in the solution space associated with mixing and stirring in ocean general circulation models (OGCMs) due to common modeling choices, namely the spatial resolution, tracer advection schemes, Reynolds number and turbulence closures. In many cases the assessment of errors is limited by the observational data set, therefore, large eddy simulations from a spectral element Boussinesq solver are taken as ground truth. First, the lock-exchange problem is used to quantify the temporal evolution of mixing from shear-driven stratified overturns. It is found that mixing in an OGCM is more sensitive to the choice of grid resolution than any other parameters tested here. The results do not monotonically converge towards the ground truth as the resolution is refined. Second, stirring of a passive tracer by submesoscale eddies generated by surface density fronts is considered. We find that using a second-order turbulence closure leads to an accurate representation of the restratification in the mixed layer.

Original languageEnglish (US)
Pages (from-to)43-62
Number of pages20
JournalOcean Modelling
Volume83
DOIs
StatePublished - Dec 1 2014

Fingerprint

Buoyancy
buoyancy
general circulation model
Turbulence
turbulence
tracer
density front
modeling
overturn
large eddy simulation
Advection
Large eddy simulation
ocean
temporal evolution
Reynolds number
mixed layer
eddy
advection
spatial resolution

Keywords

  • LES
  • Mixing
  • OGCM
  • Stirring
  • Submesoscale

ASJC Scopus subject areas

  • Atmospheric Science
  • Oceanography
  • Geotechnical Engineering and Engineering Geology
  • Computer Science (miscellaneous)

Cite this

On modeling turbulent exchange in buoyancy-driven fronts. / Marques, Gustavo M.; Ozgokmen, Tamay M.

In: Ocean Modelling, Vol. 83, 01.12.2014, p. 43-62.

Research output: Contribution to journalArticle

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