A Two-Day Case Study: Comparison of Turbulence Data from an Unmanned Aircraft System with a Model Chain for Complex Terrain

• Published in: Boundary-layer meteorology Vol. 180; no. 1; pp. 53 - 78
• Main Authors: zum Berge, Kjell, Schoen, Martin, Mauz, Moritz, Platis, Andreas, van Kesteren, Bram, Leukauf, Daniel, El Bahlouli, Asmae, Letzgus, Patrick, Knaus, Hermann, Bange, Jens
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.07.2021; Springer; Springer Nature B.V
• Subjects: Aerodynamics; Airborne remote sensing; Airborne sensing; Analysis; Atmospheric Protection/Air Quality Control/Air Pollution; Atmospheric Sciences; Case studies; Chains; Computational fluid dynamics; Deceleration; Drone aircraft; Earth and Environmental Science; Earth Sciences; Escarpments; Force and energy; Inclination angle; Mathematical models; Mean winds; Meteorological research; Meteorology; Numerical models; Numerical weather forecasting; Research Article; Sensors; Terrain; Turbulence; Turbulence data; Unmanned aerial vehicles; Unmanned aircraft; Weather forecasting; Wind; Wind direction; Wind speed; Turbulence measurement; Wind energy; Unmanned aircraft system; Complex terrain
• ISSN: 0006-8314; 1573-1472
• DOI: 10.1007/s10546-021-00608-2

The airborne measurement platform MASC-3 (Multi-Purpose Airborne Sensor Carrier) is used for measurements over a forested escarpment in the Swabian Alps to evaluate the wind field. Data from flight legs between 20 and 200 m above the ground on two consecutive days with uphill (westerly) flow in September 2018 are analyzed. In the lowest 140 m above the ground a speed-up is found with increased turbulence and changes in wind direction directly over the escarpment, whereas in the lowest 20 to 50 m above the ground a deceleration of the flow is measured. Additionally, simulation results from a numerical model chain based on the Weather Research and Forecasting (WRF) model and an OpenFOAM (Open Source Field Operation and Manipulation) model, developed for complex terrain, are compared to the data captured by MASC-3. The models and measurements compare well for the mean wind speed and inclination angle.