Interpreting weak backscattering signals: new results

ABSTRACT

The interpretation of lidar information was carried out here inverting the weak backscattering signals returned from a homogeneous atmosphere where atmospheric parameters are constant in space. It was performed interpreting weak backscattering signals using the linear approximation and the preliminary calculated value of the extinction coefficient. The analysis of the systematic errors was carried out for various distances where the backscattering signal power was measured. It was shown that the systematic errors of the extinction coefficient can exceed the systematic errors of the backscattering signal power by almost a factor of 20. There was analysed the influence of the systematic errors of the background light on the results of the lidar information interpretation. The result of the background light determination cannot be accurate enough if it is found using data obtained before sending the impulse. It was shown that the relative error of this value can be ˂1% but the relative error of the extinction coefficient determination can be ˃100%. There were analysed the experimental results and the results of computations of the scattered irradiance with absence and presence of water in the inhomogeneous coating of the aerosol particles. It was shown that the developed models adequately describe the process of scattering by a particle. It was found that the use of adequately describing models can significantly reduce the error of optical aerosol sizing.