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The influence of molecular scattering models on aerosol optical properties measured by high spectral resolution lidar (HSRL) is experimentally investigated and theoretically evaluated. The measurements analyzed in this study were made during three field campaigns by the German Aerospace Center airborne HSRL. The influence of the respective theoretical model on spaceborne HSRL retrievals is also estimated. Generally, the influence on aerosol extinction coefficient can be neglected for both airborne and spaceborne HSRLs. However, the influence on aerosol backscatter coefficient depends on aerosol concentration and is larger than 3% (6%) at ground level for airborne (spaceborne) HSRLs, which is considerable for the spaceborne HSRL, especially when the aerosol concentration is low. A comparison of the HSRL measurements and coordinated ground-based sunphotometer measurements shows that the influence of the model is observable and comparable to the measurement error of the lidar system.

An airborne high spectral resolution lidar (HSRL) based on an iodine absorption filter and a high-power frequency-doubled Nd:YAG laser has been developed to measure backscatter and extinction coefficients of aerosols and clouds. The instrument was operated aboard the Falcon 20 research aircraft of the German Aerospace Center (DLR) during the Saharan Mineral Dust Experiment in May-June 2006 to measure optical properties of Saharan dust. A detailed description of the lidar system, the analysis of its data products, and measurements of backscatter and extinction coefficients of Saharan dust are presented. The system errors are discussed and airborne HSRL results are compared to ground-based Raman lidar and sunphotometer measurements.