Evolution of Aeolus Atmospheric and Solar Background Signals

Kurzfassung

The laser signals backscattered by air molecules are one of the system parameters which are regularly monitored to assess the ALADIN instrument performance on board the Aeolus satellite. In the presentation the approach to derive these signals for clear sky conditions, avoiding interfering backscattered signals from cloud particles and aerosols, is outlined. The long-term evolution of these so-called atmospheric signals (AS) is presented and discussed for the FM-A and FM-B periods. In doing so, comparisons with the UV emit energy are provided in order to facilitate the understanding of the AS evolution. Additionally, the evolution of the solar background signals during the mission lifetime is presented and discussed, in particular their yearly cycle in time and location. These signals are applied to correct the atmospheric Rayleigh and Mie signals. Their monitoring is also important due to their noticeable influence on the Rayleigh channel wind errors.