Optimization of turbulence measurements for radar, lidar and sonic anemometers

Aviation has an increasing interest in monitoring the local wind field to enhance aviation safety and to increase the airport capacity. To this end measurements of turbulence intensity, wake vortex detection and wake vortex monitoring are important. The turbulence intensity can be quantified with the eddy dissipation rate (EDR). At this time no generally accepted algorithm for EDR retrievals from experimental data exists. An EDR retrieval algorithm intended for turbulence warning and forecasting must be able to resolve 1. high-intensity values to avoid turbulence encounters and 2. low-intensity values that enhances the wake vortex lifetime. Comparisons of EDR retrievals by different instruments are made in several studies, e.g. Chan (2011); Meischner et al. (2001); O’Connor et al. (2010). EDR can be retrieved from measurements of in-situ sonic anemometers; remotely from radar / lidar observations; with balloon borne soundings or with aircraft measurements. Spatial or temporal sampling of the signal may be used, where the signal can be velocity, humidity or temperature. Further analysis gives the EDR, by using the variance, structure functions or a least squares fit of the power spectrum. An essential problem with all these measurements is that there is no reference to true EDR...