Production and destruction of eddy kinetic energy in forced submesoscale eddy-resolving simulations
MetadataShow full item record
We study the production and dissipation of the eddy kinetic energy (EKE) in a submesoscale eddy field forced with downfront winds using the Process Study Ocean Model (PSOM) with a horizontal grid resolution of 0.5 km. We simulate an idealized 100 m deep mixed-layer front initially in geostrophic balance with a jet in a domain that permits eddies within a range of O(1km–100 km). The vertical eddy viscosities and the dissipation are parameterized using four different subgrid vertical mixing parameterizations: the k−ϵ,k−ϵ, the KPP, and two different constant eddy viscosity and diffusivity profiles with a magnitude of O(10−2m2s−1) in the mixed layer. Our study shows that strong vertical eddy viscosities near the surface reduce the parameterized dissipation, whereas strong vertical eddy diffusivities reduce the lateral buoyancy gradients and consequently the rate of restratification by mixed-layer instabilities (MLI). Our simulations show that near the surface, the spatial variability of the dissipation along the periphery of the eddies depends on the relative alignment of the ageostrophic and geostrophic shear. Analysis of the resolved EKE budgets in the frontal region from the simulations show important similarities between the vertical structure of the EKE budget produced by the k−ϵk−ϵ and KPP parameterizations, and earlier LES studies. Such an agreement is absent in the simulations using constant eddy-viscosity parameterizations.
© The Author(s), 2016. This is the author's version of the work and is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ocean Modelling 105 (2016): 44-59, doi:10.1016/j.ocemod.2016.07.002.
The publisher requires that this item be embargoed until 2018-07-16. Please check back after 2018-07-16.
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivatives 4.0 International
Showing items related by title, author, creator and subject.
du Plessis, Marcel; Swart, Sebastiaan; Ansorge, Isabelle; Mahadevan, Amala (John Wiley & Sons, 2017-04-08)Traditionally, the mechanism driving the seasonal restratification of the Southern Ocean mixed layer (ML) is thought to be the onset of springtime warming. Recent developments in numerical modeling and North Atlantic ...
The occurrence, drivers, and implications of submesoscale eddies on the Martha’s Vineyard Inner Shelf Kirincich, Anthony R. (American Meteorological Society, 2016-08-19)The occurrence, drivers, and implications of small-scale O(2–5) km diameter coherent vortices, referred to as submesoscale eddies, over the inner shelf south of Martha’s Vineyard, Massachusetts, are examined using ...
Kassis, Patricia (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2000-08)With Lagrangian and hydrographic data taken in the deep Brazil Basin, we identify several submesoscale coherent vortices (SCVs). These features contrast with SCV paradigms in that float data indicate approximately equal ...