Validation of canopy bidirectional reflectance models with ASAS imagery of a spruce forest in Maine

摘要

Advanced Solid-state Array Spectroradiometer (ASAS) directional imagery of a spruce forest is used in an initial validation of the Li-Strahler geometric-optical model and the Li-Strahler hybrid geometric-optical radiative-transfer model. Although the magnitudes of the modeled principal plane bidirectional reflectances generally correspond to the ASAS measurements, the geometric-optical model results reproduce the trends of the ASAS reflectances more closely. Both models tend to overestimate the impact of mutual shadowing at large view zenith angles.