The impact of multi‐angular measurements on the accuracy of land‐surface Albedo retrieval: Peliminary results for the proposed ESA LSPIM mission

Abstract

This paper documents, through a sensitivity study, the retrieval accuracy of the albedo and the bidirectional reflectance factor (BRF) field as a function of the number of observations and their angular distribution. A BRF data base is generated for different surface types, solar positions, and wavelengths. A realistic amount of random noise is added to approximate actual measurement conditions. A parametric BRF model is inverted against the noisy data strings of variable lengths and subsequently used in a forward mode to reconstruct the BRF field and estimate the albedo. The retrieval accuracy is estimated by comparing the original and the reconstructed fields and values. For a single observation, the retrieval accuracy based on the assumption of a Lambertian surface reflectance is compared to the one based on the assumption of a typical BRF field.