Effect of topography on average surface albedo in the ultraviolet wavelength range

摘要: The reflectivity of the 22 km × 24 region surrounding Sonnblick Observatory near Salzburg, Austria (3104-m altitude, 47.05 °N, 12.95 °E), was calculated with a three-dimensional albedo model. average at 305 and 380 nm for different solar zenith angles, ground reflectances, azimuth angles. To determine geometrical effects, we first carried out simulations without taking account effects atmosphere. ratio to corresponding flat surface area (area same characteristics) always less than 1 showed decrease increasing angle diminishing reflectance. Even when reflectance 100%, 1. effect atmosphere then taken into consideration in these calculations found diminish reflected components. This compensated for, however, by scattered irradiance. Finally, real conditions (nonhomogeneous reflectivities) were performed snow lines region. albedos obtained all surroundings covered 0.32–0.63 low angles 0.38–0.77 40° angle.