Meso- and Fine-Scale Modeling over Complex Terrain: Parameterizations and Applications

Abstract

This chapter discusses the current status, success, and especially chal- lenges of applying mesoscale numerical models to simulate atmospheric processes over areas of complex terrain. These include thermally-induced circulations, gap flows, mountain waves, and boundary layer structure and evolution in mountainous regions. The choice of model configuration (e.g. choice of coordinate system, horizontal and vertical resolution, grid nesting, and lateral boundary conditions) and physical parameterizations (e.g. boundary layer, land surface, and radiation parameterizations) may affect the performance of mesoscale models in complex terrain. Application of large-eddy simulation (LES) to complex-terrain processes is also discussed. Examples of model simulations related to several recent field studies in mountainous areas are used to illustrate the issues and challenges. 10.1