Analysis of X-band Doppler polarimetric weather radar returns from a wind farm

This contribution will present the results of a field campaign aimed at analysing the polarimetric and Doppler signatures of wind turbines. The campaign took place in the north-eastern part of Switzerland in March 2019. A mobile X-band Doppler polarimetric weather radar was deployed roughly 8 km away from a wind farm consisting of 3 large (199.5 m total height) wind turbines. Measurements were performed on a 24/7 basis with dedicated scans, allowing the gathering of data in fairly different meteorological conditions. The scan strategy consisted in a set of PPIs at closely spaced elevation angles (between 0.1° and 0.2°) over a window widely covering the location of the wind turbines, followed by a set of RHIs at closely spaced azimuth angles over a similar window. The whole scan was repeated every 45 min. A large dataset was gathered in this way of basic polarimetric and Doppler moments (reflectivity, differential reflectivity, co-polar correlation, differential phase, Doppler velocity and Doppler spectrum width) as well as Doppler spectra. An extensive statistical analysis has been performed taking into account the windmill operation conditions kindly provided by the windfarm manager