Planetary albedo

It is defined as the ratio of reflected radiation from the surface to incident radiation upon it. The average overall albedo of Earth, its planetary albedo, is 30 to 35%, because of the covering by clouds, but varies widely locally across the surface, depending on the geological and environmental features. Albedos of typical materials in visible light range from up to 0.9 for fresh snow, to about 0.04 for charcoal, one of the darkest substances. Melting ice caps and clearing forests will reduce the reflected radiation whereas increasing cloudiness will increase Albedo