An analysis of the nonhydrostatic dynamics in numerically simulated antarctic katabatic flows

Abstract

A series of two-dimensional numerical experiments was conducted in order to describe the role of nonhydrostatic dynamics in simple Antarctic katabatic flows. The results presented include a comparison of the thermodynamic and dynamic fields produced by hydrostatic and nonhydrostatic numerical simulations. The source of the differences in the simulations was diagnosed based on an analysis of the model equation tendencies as well as calculated components of the pressure gradient force. Over most of the terrain slope, the nonhydrostatic effects were found to be insensitive to the model horizontal resolution, for a grid spacing ranging from 5 to 100 km.