Stochastic subgrid modelling for atmospheric large eddy simulations

Abstract

Dynamical subgrid scale parameterizations of stochastic backscatter and eddy dissipation have been calculated for typical atmospheric turbulent flows on the sphere. A methodology based on a stochastic model representation of the subgrid scale eddies in direct numerical simulations, and with wide applicability to fluid flows, has been employed. Large eddy simulations incorporating these subgrid scale parameterizations are found to have energy spectra that compare closely with the results of higher resolution direct numerical simulations for both barotropic and baroclinic turbulent flows. References

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