Inversion techniques for determining the droplet size distribution in clouds: numerical examination.

The Phillips-Twomey and Backus-Gilbert inversion techniques are applied to determine the size distribution of water droplets in clouds from light scattering data at backward angles. The data are generated numerically from the Mie scattering functions and an assumed cloud model. The size distribution is recovered from these data using the two inversion techniques and is compared with the assumed model. It is found that the Phillips-Twomey technique gives better agreement between the assumed and recovered size distributions than the Backus-Gilbert technique. Also, it is more stable to random errors artificially introduced into the scattering data.