The cloud-screened and atmospherically-corrected surface reflectances are normalized directionnally by inversion of a kernel-driven bidirectional reflectance model (Roujean et al., 1992) following the approach presented in Hagolle et al. (2004). The inversion, over a synthesis period of 30 days with a sliding window of 10 days, yields three coefficients : a nadir-zenith reflectance, a geometric and a volumetric coefficients. They are used with the angular kernels integrated over viewing directions and over solar directions to calculate the directional and the hemispheric spectral albedo, successively. The spectral integration over broadband (visible : [400-700nm], NIR : [700, 4000nm], total : [300 - 4000nm]) is then carried out using conversion coefficients provided by the team MATIS from CNRM/Météo-France. The image below is an example of broadband VEGETATION albedo.

Broadband hemispheric surface albedo derived from VEGETATION data over South-West of France, August 2000.