ANTARCTIC SKIES .2. CHARACTERIZATION OF THE INTENSITY AND POLARIZATION OF SKYLIGHT IN A HIGH ALBEDO ENVIRONMENT

Work in the Antarctic during spring 1990 has been aimed at obtaining a full understanding of the properties of light falling onto the Antarctic continent. The present paper describes details of the intensity and polarization distribution of the indirect skylight in the Sun-zenith plane, and these are also compared with measurements made at Wellington, New Zeland. The light in Antarctica is shown to have a low maximum polarization of about 40%, essentially independent of wavelength across the visible spectrum. The intensity is strongest for light coming from directions in opposition to the Sun. A simple model shows that these features are due to multiple scattering in the atmosphere induced by the high snow albedo. A comparison is made with functions derived from theory.