スペースライダーの観測における多重散乱の影響

抄録

A multiple scattering contribution is one of the major problems to be solved in the lidar measurements of clouds from space. This paper discusses the effects of the multiple scattering on the lidar signals measured from space and on the retrieval of the extinction profiles. A Monte Carlo model, which directly simulates the trace of photons in the clouds, has been developed for multiply scattered lidar signals. The probablity that the photon returns to the lidar receiver is calculated. By using the Monte Carlo model, numerical simulations have been made for space-borne lidar signals scattered from clouds. The results show that significant contributions of the multiple scattering in the lidar return signals lead to bias in the retrieval of the extinction coefficient of clouds. A technique to estimate the multiple scattering contribution in the return signal by using multiple field of view (MFOV) lidar has been developed by which the bias is considerably decreased.