Wednesday, 25 January 2012
Trial Simulation of Windshear Cases At the Hong Kong International Airport Using High Resolution Numerical Weather Prediction Model
An attempt is ongoing at the Hong Kong Observatory to use high-resolution numerical weather prediction (NWP) model to support aviation weather service at the Hong Kong International Airport (HKIA). The NWP model, called Aviation Model (AVM), has a spatial resolution down to 200 m for simulations in the region around HKIA. Two possible models have been tested as tentative candidates of AVM, namely, Weather Forecasting and Research (WRF) model and Non-hydrostatic Model (NHM) adopted from Japan Meteorological Agency. Based on selected case studies, it was found that WRF has lower root-mean-square-error for wind forecasting up to 9 hours ahead, and its efficient modelling code makes it a possible NWP model for real-time execution of AVM in the future. The performance of WRF in the simulation of significant windshear at HKIA is also studied by considering a number of typical windshear cases. The simulation of sea-breeze related windshear is quite successful, and the headwind change as observed from flight data could be reproduced in the model results. For terrain-induced windshear, WRF is able to capture the salient wind patterns, though the simulated headwind profiles may not capture the abrupt changes of the wind at times.