Aspect ratio as a function of particle radius: Inversion of extinction and scattering data

The sun and sky photometry made concurrently or, alternatively, simultaneous measurements of extinction and scattering data both represent a valuable tool for gathering the information on aerosol particles. Most typically the size distribution and/or refractive index of aerosol particles can be inferred from multispectral and/or multiangle optical data. Extraction of size-dependent aspect ratio of aerosol particles from optical data is a highly non-trivial task since the kernel of the particular integral equation is a non-linear function of the sought solution. The iterative solution to this problem is introduced and demonstrated on synthetically generated data. It is shown that retrieval of size-dependent aspect ratio is possible even for complex morphologies, most typically for irregularly shaped dust particles.