P62     Characterization of the boundary layer structures and local airflow over the complex terrain in Taiwan using high resolution WRF model.

 

Wang, Yu-Tzu, Fang-Yi Cheng, National Central University, Taiwan, and Hyeyum Hailey Shin, National Center for Atmospheric Research

 

It is difficult to accurately simulate the development of atmospheric motions over the mountainous area. In order to understand the characteristics of planetary boundary layer (PBL) structures and the local circulation over the complex terrain in Taiwan, the Weather Research and Forecasting (WRF) Model at fine resolution (600-m) was applied. In addition, two different PBL scheme (Yonsei University, YSU and Shin-Hong scale-aware, SH) were applied to study the influence of the PBL physical processes on the simulated vertical structures over the complex terrain in Taiwan.
  The main difference between the two PBL schemes is the algorithm for nonlocal PBL parameterization and the scale dependency of the subgrid-scale transport. The SH PBL scheme considers a more accurate nonlocal heat flux profile and multiplies the grid-size dependency function with the vertical transport term which is found in large-eddy simulation. By using SH PBL scheme, the resolved motion can be improved and the simulated convection structure can be maintained at the gray zone resolution.
  Simulation results were evaluated with the observed sounding data and surface station to characterize the PBL structures and local air flow over the ventral mountainous area of Taiwan.