A Joint Lidar Solar Radiometer Experiment

Abstract

Remote sensing of the lower atmosphere by lidar yields profiles of the backscattering cross section along the optical path. These may be simply converted to give a qualitative picture of the distribution of atmospheric aerosol, but quantitative values can only be obtained if further information is available on aerosol properties such as refractive index and size distribution. In the experiments described below, use was made of a solar radiometer to give information on the second of these. This is then used to calculate an improved value for the ratio of backscattering to aerosol mass (?/m) for the interpretation of the lidar data. Comparison is made of the results of radiometer measurements, taken at a rural area outside Munich, with airborne lidar measurements of the tropospheric aerosol made in the same locality. Aerosol density profiles obtained in another flight made near Augsburg on 22 July 1977 show the presence of a heavy aerosol concentration over the city and the effects of the north wind are clearly visible.