Rayleigh-Brillouin scattering of laser light in air

Kurzfassung

The global observation of atmospheric wind profiles remains to be the highest priority need for weather forecast. Therefore, the European Space Agency ESA decided to implement the Atmospheric Dynamics Mission ADM-Aeolus to demonstrate the potential of the Doppler lidar technology for global wind profiling. Thereby, the laser of the Doppler lidar sends short pulses into the atmosphere where they are partly scattered by aerosols and molecules. The backscattered light is collected by a telescope and analyzed concerning its frequency. The frequency shift between emitted and received light, caused by the Doppler-effect, is directly proportional to the atmospheric wind speed. The accuracy of this measurement technique is significantly depending on the knowledge of the spectral distribution of the backscattered light. For the validation and the improvement of spectral line shape models of Rayleigh-Brillouin scattered light, laboratory measurements as well as atmospheric measurements were performed. In my talk, the results of these measurements and the resulting influence on remote sensing techniques are extensively discussed.