Surface Bidirectional Reflectance Distribution Function observed at global scale by POLDER/ADEOS

Abstract

The spaceborne POLDER instrument presents the unique capability of sampling the surface Bidirectional Reflectance Distribution Function (BRDF) up to about 60°viewing angle for the full azimuth range of every point on Earth at 6 km resolution, when atmospheric conditions are favorable. This paper presents examples of BRDF signatures acquired at this resolution on several terrestrial biomes (desert, steppe, grassland, boreal forest, savanna, wetland). Well identified directional signatures for all azimuths are obtained and shown to be different for each biome. Specific directional effects in the hot spot and specular directions are well observed in the data.