Energetically-Accurate Vertical Grid for Under-Resolved Quasi-Geostrophic Ocean
Rachel Robey, University of Colorado Boulder
The number of layers in regional and global-scale ocean models is computationally limited. In the resulting under-resolved regime, sensitivities to the choice of grid used in the discretization can arise in a way that would not be expected with more adequate resolution. Preliminary investigations of varying vertical grids in the MOM6 ocean model suggest significant discrepancies in the kinetic energy of the resolved flow. Using a simplified quasi-geostrophic (QG) ocean model, we investigate the role of the vertical grid on the turbulence behavior and energetics. We propose a vertical coordinate system for determining the grid layers, develop some theoretical underpinnings for the coordinate choice, and test the behavior in ideal QG simulations. The proposed grid scheme has the potential to improve the accuracy of the representation of the resolved QG baroclinic modes, their interactions, and the resulting energetics given the limitations on the number of layers.
Authors: Rachel Robey1, Ian Grooms1, Scott Bachman2
1Department of Applied Mathematics, University of Colorado Boulder, USA
2National Center for Atmospheric Research, USA
Abstract Author(s): (see above entries)