Idealized atmospheric boundary layer and tornado simulations for Wang et al. (2023) two-layer-model study.

This dataset contains the numerical simulations used in the Wang et al. (2023) study of two-layer-model in an idealized atmospheric boundary layer and an idealized tornado. That work modifies a wall model from the engineering community known as two-layer model (TLM) to a widely used atmospheric LES mode, Cloud Model 1 (CM1). LES of an idealized, neutral atmospheric boundary layer are performed first, in order to validate the implementation of the TLM in CM1. Next, simulations are performed of an idealized tornado. Simulations utilizing TLMs are compared to those employing the traditional (``semi-slip'') lower boundary condition and a recently proposed lower boundary condition that accounts for some effects of turbulence memory. The traditional lower boundary condition, which assumes statistically steady and horizontally homogeneous flow, always results in a surface stress that is opposite the wind at the lowest LES grid level. Using the other models of the near-surface turbulence allows for a wider range of surface stress directions and enhances the resolved turbulence and wind gusts.