Surface Albedo and the Filling-In of Fraunhofer Lines in the Day Sky

The observed partial filling-in (Ring effect) of solar lines in light from the sky has been explained by Brinkmann as due to rotational Raman scattering. Analogous effects in the albedo contribution are examined, and are shown to be capable of accounting for a variation with solar zenith angle, and for the marked variability that is observed. The principal effect responsible for smearing of the spectrum is probably the so-called Rayleigh wings, which can be regarded as heavily damped rotational Raman scattering in condensed matter.