A Conceptual Model of Surface Reﬂectance Estimation for Satellite Remote Sensing Images Using in situ Reference Data
For satellite remote sensing, radiances received at the sensor are not only aﬀected by the atmosphere but also by the topographic properties of the terrain surface. As a result, atmospheric correction alone does not yield output images that truly reﬂect terrain surface properties, namely surface reﬂectance (bidirectional reﬂectance factor, BRF) of objects on the earth surface. Following the concept of the radiometric control area (RCA)-based path radiance estimation method, we herein propose a statistical approach for surface reﬂectance estimation utilizing DEM data and surface reﬂectance of selected radiometric control areas. An algorithm for identiﬁcation of shaded samples and a shape factor model were also developed in this study. The proposed RCA-based surface reﬂectance estimation method is capable of achieving good reﬂectance estimates in a region where elevation varies from 0 to approximately 600 m above the mean sea level. However, further study is recommended in order to extend the application of the proposed method to areas with substantial terrain variation.
path radiance,radiometric control area,reﬂectance,shape factor