The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is a new atmospheric simulation system that merges state-of-the-art computational fluid dynamics techniques with a comprehensive non-hydrostatic equation set. OMEGA is based on an unstructured triangular prism grid that permits a horizontal grid resolution ranging from 100 km down to 1 km and a vertical resolution from a few tens of meters in boundary layer to 1 km in the free troposphere. OMEGA contains an embedded Atmospheric Dispersion Model (ADM) that permits the high resolution simulation of the advection and diffusion of either grid-based aerosols or of Lagrangian parcels of either grid-based aerosols or of Lagrangian parcels.
OMEGA is naturally scale spanning and its unstructured grid permits the addition or subtraction of grid elements at any point in space and time. OMEGA can readily adapt its grid to fixed surface or terrain features, land/water boundaries, or dynamic features in the evolving weather. The implications for the ADM are that enhanced grid resolution can be provided in localized regions such as emission sources or in the vicinity of a dust, smoke, or chemical cloud.
In this paper, we will present an overview of the atmopsheric simulation and aerosol dispersion capabilities of OMEGA. We will then discuss some validation cases