Estimation of the double-scattering component of the lidar return from multi-component atmosphere

Estimation is performed based on a theory developed by Eloranta of the double-scattering contribution to the LIDAR return from a multi-component atmosphere that may contain not only molecular (gaseous) and aerosol fractions, but other compact aerosol objects as well, such as cirrus clouds or Saharan dust layers. It is shown that the relative double-scattering component of the LIDAR return may be approximately considered as a sum of the independent relative contributions of each of the atmospheric components. Then, using appropriate models, the contribution of each component of interest is evaluated as a function of the altitude, taking into account the scattering properties of the medium under consideration, the angular divergence and the wavelength of the sensing laser beam, and the angle of view of the receiving optical system. The results obtained outline the cases when either the double scattering is negligible or corrections are necessary for the multiple scattering effects.