Self-consistency validation of subgrid scale parameterization schemes in a large-eddy simulation

In the present study,we perform a set of numerical simulations in a moderately stable boundary layer with four types of subgrid-scale parameterization schemes and attempt to evaluate the error of the vertical flux for these schemes in terms of self-consistency on the basis of the germano identity. if the effects of grid-scale components in higher wavenumbers are excluded from the analysis,the error estimated by the germano identity is insensitive to the reference data utilized. the subgrid-scale flux,evaluated by the smagorinsky model,tends to excessively weaken the positive temperature gradient at the top of the boundary layer with decreasing model resolution. the deardor and two-part models overestimate the subgrid-scale temperature flux at a coarser resolution,and the dynamic smagorinsky model tends to underestimate both the subgrid-scale momentum and the temperature fluxes throughout the entire boundary layer. the underestimation of the subgrid-scale flux found in the dynamic smagorinsky model could be attributed to a low correlation between the resolved and the parameterized components. © 2010,meteorological society of japan.