Title: Notes on Rayleigh Scattering in Lidar Signals
Authors: ADAM MARIANA
Citation: Proceedings of the 25th International Laser Radar Conference p. 19-22
Publisher: Publishing House of IAO SB RAS
Publication Year: 2010
JRC N°: JRC62364
URI: http://publications.jrc.ec.europa.eu/repository/handle/JRC62364
Type: Articles in periodicals and books
Abstract: The correct formulation for Rayleigh scattering using the classical approach [1] is used to analyze the molecular contribution in the lidar signals. Within classical approach, three atmospheric scenarios are considered: 2, 4 and 5-component atmosphere (N2 + O2, N2 + O2 + Ar + CO2 and N2 + O2 + Ar + CO2 +water vapor). Two case studies are performed to see the relative difference between retrievals using these scenarios. First case study considers 23 days measurements of air pressure, temperature and relative humidity at 31.8m. The second case study uses a radiosounding of air pressure, temperature and relative humidity. Retrievals of the aerosol extinction and backscatter coefficient are compared, using lidar signals at 355nm and 387nm. The quantum approach is used to compute the aerosol backscatter coefficient and the correction factors for the temperature-dependence of the molecular cross-sections [2]. The results show that for water vapor between 10 and 20g/kg, the relative difference between 5-component and 2-component atmosphere is between 0.5% and 1% for molecular scattering and between -0.9% and -0.4% for molecular backscattering. For aerosol backscatter (extinction) coefficient, the difference is bellow 1%. Thus a two-component atmosphere is a good approximation. Temperature correction can be ignored for N2.
JRC Directorate:Sustainable Resources

Files in This Item:
There are no files associated with this item.


Items in repository are protected by copyright, with all rights reserved, unless otherwise indicated.