High resolution weather data base for the terminal area of Frankfurt Airport

Kurzfassung

A 1-yr meteorological dataset for the terminal area of Frankfurt Airport in Germany has been generated with a numerical weather prediction system to provide a synthetic though realistic database for the evaluation of new operational aircraft arrival procedures and their associated risks. The comparison of the 1-yr dataset with a local surface wind climatology indicates that the main climatological features are recovered. A subset of 40 days is validated against measurements from a sound detection and range/radio acoustic sounding system (SODAR/RASS) taken at Frankfurt Airport. The RMS errors of wind speed and direction are between 1.5 m s s^-1 at the surface and 2 m s s^-1 at 300 m and 40°, respectively. The frequency distribution of meteorological parameters, such as the wind component perpendicular to the glide path, shear, and thermal stratification, show good agreement with observations. The magnitude of the turbulent energy dissipation rate near the surface is systematically overestimated, whereas above 100 m the authors find on average a slight underestimation. The analysis of the database with respect to crosswind conditions along the glide path indicates only a time fraction of 12% for which the crosswind is above a threshold of 2 ms^-1. A similar result is obtained using a grid point near the airport that mimics a wind profiler, which suggests that in a majority of cases a wind profiler appears sufficient to cover the expected crosswind conditions along the glide path. A simple parameterization to account for the crosswind variability along the glide path is proposed.