Airborne wind lidar measurements in the North Atlantic in 2009 supporting ESA's Aeolus mission

Abstract

The global measurement of wind profiles is considered to be of highest priority regarding the needs for numerical weather prediction (NWP). Therefore, the European Space Agency ESA implemented the ADM-Aeolus satellite mission with a scheduled launch date in 2015. It will demonstrate the potential of the Doppler wind lidar technology for providing vertical profiles of wind globally. The wind speed measurements between 0 and about 25 km are based on laser light at 355 nm that is scattered back by aerosols/clouds and molecules. A prototype of the satellite instrument was deployed in the DLR Falcon 20 aircraft and tested during an airborne campaign over Greenland, Iceland and the North Atlantic in 2009. Additionally, a well-established second wind lidar operating at a wavelength of 2 μm was installed. Thus, the first successful flights worldwide were performed with two wind lidar instruments on-board the same aircraft using different detection principles for the wind measurement. Comparisons of the wind speeds retrieved from both lidar systems allowed the validation of the measurement principle of the satellite and the optimisation of retrieval algorithms. Measured wind fields from both lidars will be presented along with analyses from ECMWF NWP models. For the molecular and the aerosol channel of the prototype instrument, statistical comparisons yielded random errors of less than 2.5 m/s and 1.5 m/s, respectively.