Super-high-resolution numerical simulation of atmospheric turbulence in an area of complex terrain

This work studies the atmospheric turbulence in cross-mountain airflow at the Hong Kong International Airport (HKIA) using Regional Atmospheric Modelling System (RAMS) version 4.4 with a horizontal grid size of 50 m. Deardorff turbulence parameterization scheme is employed in the innermost model domain. The model directly calculates the eddy dissipation rate (EDR), a metric for turbulence intensity in aviation, and the results are compared with LIDAR measurements of EDR.

In the nesting run of the numerical model at this super-high spatial resolution, one major challenge is the lack of an appropriate turbulence parameterization scheme in the 'intermediate' length scale in the order of several hundred metres. The sensitivity of the modelling results to the choice of the turbulence parameterization scheme in this 'intermediate' scale will be discussed.