AbstractsGeography &GIS

The "albedo", A, of a surface is defined as the ratio of, Ir, the radiation reflected by the surface and Io, the radiation incident upon the surface; or, A=Ir/Io. It is expressed either as a percentage or simply as a number. The term "reflectivity coefficient” is used by some authors for the same quantity. It is also understood that the albedo is restricted to the solar component of the radiation spectrum. For the present study the range of wavelengths is set effectively by the capability of the sensing instrument used which, in this case, is limited to the range 0.3 to 2.0 microns for the Kipp and Zonen Solarimeter. The energy emitted by the sun contained in the wavelengths greater than 2.0 microns is small by comparison to the energy contained in the wavelengths specified and can be safely ignored.