Lidar is used to measure atmospheric aerosol, and horizontal visibility is retrieved based on lidar measurement data. In the process of visibility retrieval, it’s manually ascertaining linear region that existed in the curve of data, which is difficult for computer. An algorithm is presented to ascertain the linear region and gives out the horizontal visibility automatically. A group of lidar measurement data is processed by the algorithm, and the results show its practicability.
Factors of atmosphere was taken into account for the attenuation coefficient calculation. Atmospheric attenuation of whole atmosphere was given. The result contrast was done between ours and literature. And they fit well.