Albedo of the U.S. Great Plains as Determined from NOAA-9 AVHRR Data

Abstract

The seasonal variation of surface albedo is derived from NOAA-9 AVHRR observations of the US. Great Plains during the snow-free months of 1986 and 1987. Monthly albedo maps are constructed using a simple model-independent technique which includes recording of the cloud-free data by 9-day satellite repeat cycle, spatial interpolation of the data averaging on each day of the cycle, and averaging over the cycle to obtain a monthly mean estimate. The surface albedo is obtained by applying a narrowband-to-broadband conversion and a simple atmospheric correction to the clear-sky albodo of each mouth. The phenological changes of four target areas (two forest lands and two croplands) are analyzed. In some areas, crop development can double the albedo values within the growing season. Such changes are important in radiation budget calculations. On the whole, the results are in good agreement with tabulated values based on albedos reported in the literature for various surface types.