Following a brief review of single-scattering by airborne particles, theoretical results about the sensitivity of single-scattering measurements to aerosol properties will be discussed: (1) While the phase-function alone offers reasonable constraints on the size distribution for larger particles, all single-scattering measurements fail to constrain the size distribution for very-small particles. (2) Uncertainty estimates for particle number concentration are much worse than for other loading parameters, like particle surface-area density and particle volume density. (3) Polarimetric measurements improve retrieval uncertainty estimates in the size distribution and complex refractive index for larger particles. (4) Measuring the absorption coefficient becomes increasingly important for determining the complex refractive index of smaller particles as their scattering behavior approaches the Rayleigh limit.
While these results apply to single-scattering measurements only, they may provide useful intuition about satellite and aircraft retrievals of aerosols in the atmosphere.