THE VARIABLE APPEARANCE OF THE EARTH FROM SATELLITES

Abstract

The appearance of the Earth as seen from space changes continually. These changes in brightness and in color are produced by interactions between (1) geographical factors, such as coasts and mountains; (2) seasonal factors, such as the brightness changes due to the deposition and disappearance of snow; and (3) meteorological effects such as the cloud patterns indicative of the formation, development, and movement of tropical and extra-tropical disturbances. The region of the spectrum in which the Earth is viewed influences its appearance. For example, to a satellite, clouds appear as high-energy sources in reflected short-wave, solar energy, but as cold, low-energy sources in emitted radiation. All these effects are illustrated with pictures and measurements from TIROS satellites. A high resolution picture recovered from the Mercury project is also included.