Retrieval and application of the aerosol lidar ratio based on polarized Mie lidar

The aerosol optical properties over Nanjing were measured using polarized Mie lidar. Typically, retrieving aerosol optical parameters from Mie scattering lidar data requires the use of a predetermined aerosol lidar ratio, often assumed to be constant. However, this assumption can lead to significant retrieval errors. To overcome this, AERONET data were employed to develop a model for the lidar ratio based on depolarization ratios. This model enabled more accurate retrieval of aerosol lidar ratio profiles using polarized backscattering signals. To further improve the accuracy of aerosol optical parameter inversion, the model was refined with more precise thresholds for distinguishing between dust and spherical particles. A comparative analysis was conducted between the aerosol optical parameters retrieved using the optimized model and those obtained with a fixed lidar ratio. Additionally, the influence of meteorological factors on the vertical distribution of aerosols was examined. Finally, a comprehensive analysis of an aerosol pollution event was conducted based on lidar and sun photometer observations.