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The Raman lidar has been developed and installed in the Beijing from November to December in 2014 for the observation of the spatial and vertical characteristics of aerosol and water vapor in the planetary boundary layer. During the experiments, the Raman lidar operates in the automatic and continuous mode with the spatial resolution of 7.5 m and the temporal resolution of 15 min. The observation results show that the aerosol extinction always increases along with the greater content of water vapor and the lower height of planetary boundary layer. It implies that the decrease of air quality in Beijing is associated with the water vapor in the air and the height of planetary boundary layer beside the enrichment of local and transported aerosols.

A high spectral resolution lidar(HSRL) based on injection-seeded laser and iodine absorption filter has been developed. The basic principle, data processing method and configuration of HSRL were introduced. The HSRL measurement of atmospheric transmission in cloud and dust cases were presented,and compared with the results retrieved by the traditional Fernald method. Due to the nonidentity in physical and optical properties of different aerosols and cloud, the lidar ratio assumed in Fernald method cannot agrees well with the real atmosphere and produces considerable error in atmospheric transmission. Utilizing different spectral width of molecular scattering and particle scattering, the HSRL could separate two kinds of signals with iodine filter. Therefore, HSRL can measure the atmospheric transmission quantitatively without the additional assumption of lidar ratio.