Simulation of multiple scattering in lidar measurements using pure rotational Raman scattering (PRRS)

Pure rotational Raman scattering signals from atmospheric gases such as nitrogen and oxygen can be used to deduce the temperature of the atmosphere. Previously, this method has been successfully implemented as a remote temperature sensing lidar system. In this paper, theoretical studies of the method have been carried out using Monte Carlo simulations for different temperature profiles from radio sonde data. The geometry of the lidar as well as the aerosol profiles of the atmosphere can be specifically defined in this method. It is important to understand whether or not multiple scattering will have a significant effect on the accuracy of temperature retrieval from the measured lidar returns. From the exact pure rotational Raman scattering matrix, we have computed the lidar returns of individual Raman lines. We have given the ratios of multiple to single scattering return signals for atmospheres without clouds, with water clouds and with cirrus clouds. The results indicate that the effect of multiple scattering does not give errors to the temperature inversion for typical atmospheric conditions.