A bidirectional reflectance model of the Earth's surface for the correction of remote sensing data

TLDR

The semi‑empirical model uses three adjustable parameters to represent surface bidirectional reflectance as the sum of diffuse reflection from opaque facets and volume scattering from dispersed facets, making it applicable to heterogeneous surfaces and suitable for inclusion in remote‑sensing time‑series correction algorithms. Comparisons with in‑situ data show satisfactory agreement across visible and near‑infrared bands, indicating the model can substantially reduce surface‑bidirectional fluctuations in multitemporal remote‑sensing datasets.

Abstract

A surface bidirectional reflectance model has been developed for the correction of surface bidirectional effects in time series of satellite observations, where both sun and viewing angles are varying. The model follows a semiempirical approach and is designed to be applicable to heterogeneous surfaces. It contains only three adjustable parameters describing the surface and can potentially be included in an algorithm of processing and correction of a time series of remote sensing data. The model considers that the observed surface bidirectional reflectance is the sum of two main processes operating at a local scale: (1) a diffuse reflection component taking into account the geometrical structure of opaque reflectors on the surface, and shadowing effects, and (2) a volume scattering contribution by a collection of dispersed facets which simulates the volume scattering properties of canopies and bare soils. Detailed comparisons between the model and in situ observations show satisfactory agreement for most investigated surface types in the visible and near‐infrared spectral bands. The model appears therefore as a good candidate to reduce substantially the undesirable fluctuations related to surface bidirectional effects in remotely sensed multitemporal data sets.