A RAPID ALBEDO INVERSION METHOD FROM NADIR REFLECTANCE BASED ON MODIS BRDF PRODUCT

Land surface albedo is one of the key parameters in the radiation budget, the hydrological cycle and climate modeling studies. It is wildly known that large errors may occur in the estimation of surface albedo without taking into consideration the anisotropy reflectance effect, which is a general feature of the earth surface. In the present study, a new approach that utilizes prior BRDF knowledge, which is extracted from MODIS BRDF product, for estimating surface albedo has been proposed. The density plot of MODIS BRDF model parameters shows model parameters was in obvious assembled distribution. The prior BRDF knowledge was extracted from the most concentrated (top 60 percent) area. Results show that the prior BRDF-based albedo from simulated nadir reflectance enables 90 percent of all pixels have the absolute difference between -0.02 and 0.02.