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Oliver Reitebuch, Christian Werner, Ines Leike, Patricia Delville, Pierre H. Flamant, Alexander Cress, and Dirk Engelbart

Abstract

The airborne Wind Infrared Doppler Lidar (WIND) has been developed through French–German cooperation. The system is based on a pulsed 10.6-μm laser transmitter, a heterodyne receiver, and a conical scanning device. To the authors' knowledge, it is the first airborne Doppler lidar for atmospheric research to retrieve the whole tropospheric wind profile between the ground and the flight level looking downward. The wind vector is measured with the velocity-azimuth display (VAD) technique with a vertical sampling of 250 m. The first flights on board the DLR Falcon 20 aircraft were performed in 1999. Results of a comparison among WIND, radiosondes, wind-profiler radar measurements, numerical models, and simulations are presented. It is shown that the correspondence of airborne WIND measurements with those of other instruments or models is better than 1.5 m s−1 and 5° for the horizontal wind vector. These results show the excellent capability of conical scanning Doppler lidars to provide unique insights into mesoscale dynamic processes and progress made toward future spaceborne systems.

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Ines Leike, Jürgen Streicher, Christian Werner, Viktor Banakh, Igor Smalikho, Werner Wergen, and Alexander Cress

Abstract

Doppler lidars measure the range-resolved line-of-sight wind component by extracting the Doppler shift of radiation backscattered from atmospheric aerosols and molecules. A virtual instrument was developed to simulate wind measurements by flying virtually over the atmosphere. The atmosphere contains all components that influence the lidar, that is, wind, turbulence, aerosols, clouds, etc. For a selected time period, a dataset of the atmospheric conditions from the global model and the local model was provided by the German Weather Service. Three different Doppler lidar systems were simulated for this report: a coherent airborne conical scanning 10-μm Doppler lidar, a 10-μm and a 2-μm spaceborne system, and a spaceborne incoherent ultraviolet Doppler lidar.

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