Generation of eddy dissipation rate map at the Hong Kong International Airport based on Doppler LIDAR data

Turbulent airflow mostly occurs at HKIA when winds blow off the hills on the Lantau Island (with peaks rising to almost 1000 m to the south of the airport) from east to southwest. In a previous study by Chan et al. (2005), turbulence intensity in terms of EDR was measured directly using a staring LIDAR beam. This paper extends this study to calculate the spatial distribution of EDR (so-called EDR map) with the ultimate goal of monitoring the turbulence over all the runway corridors of HKIA using the LIDAR.

The EDR map is calculated based on plan-position indicator (PPI) scans of the LIDAR. The whole scan area is divided into a number of small sectors, each having a size of about 1 km in range and 20 degrees in azimuth. Velocity structure function is evaluated in every sector and compared with the theoretical von Kármán model to estimate the EDR. This paper gives an overview of the calculation method, shows some examples of EDR map in terrain-disrupted turbulent airflow at HKIA and examines the quality of the EDR value so obtained by comparing against the measurements of a ground-based anemometer.