Estimation and validation of high temporal and spatial resolution albedo

Land surface albedo is a critical physical variable controlling the distribution of radiative energy between the atmosphere and surface. In this paper, we proposed a method to estimate high temporal and spatial resolution land surface shortwave albedo. The method consisted of three main steps: 1. to generate fine-resolution shortwave albedo with Landsat-7 ETM+ data; 2. to generate coarse-resolution shortwave albedo based on MODIS albedo products; 3. to estimate high temporal and spatial resolution albedo using revised STARFM model. For the problem that the estimation accuracy degrades somewhat in heterogeneous regions, we further improved STARFM model by introducing the idea of mixed pixel decomposition. Comparing with ETM+ albedo, the estimated albedo were of reasonable accuracy with root mean square error (RMSE) less than 0.03, and maintained a high level of spatial detail. Results obtained by using improved model showed higher correlation and smaller deviation compared with ETM+ albedo.