High-Resolution Numerical Simulations of Surface Wind Variability by Resolving Small-Scale Terrain Features

Abstract

The land of Japan is characterized by complex and steep terrains, which influence locally heavy rainfall and severe wind. Due to high variability of wind speed, gusty winds are significantly affected by small-scale terrains. Thus, it is important to understand the effects of complex and steep terrains on the development of wind gusts in addition to the understanding of the physical processes of microscale meteorological phenomena such as tornadoes and downbursts. This study investigates the variability of severe local winds by conducting high-resolution numerical simulations that incorporate the 50-m mesh digital elevation map of the Geographical Survey Institute of Japan. By resolving small-scale terrain features, it is shown that the high-resolution simulations can represent the short-term and small-scale variability of surface winds.