Figure 7. Maps of the annual mean all-sky albedo (calculated as the reflected solar radiation divided by the incident solar radiation) for CAS-LSM versus MODIS observation for the years 2001–2002. For each grid cell, only months where the monthly mean solar radiation (Satm, 100 W∙m-2) are included in the albedo calculation, which reduces, but does not eliminate, the impact of the low snow albedo bias in the MODIS data at high solar zenith angles (Wang and Zender 2010). The MODIS all-sky albedos were derived from the black-sky (direct) and white sky (diffuse) near-infrared and visible waveband albedos by weighting them according to the CAS-LSM partitioning of Satm into these components.