Surface information retrieval from optical/microwave data: potentials and limits of synergistic approaches

In retrieving surface parameters from remotely sensed data, especially over vegetated land surfaces, synergistic use of optical and microwave instruments appears to be a more powerful tool than when each considered alone. Although this is especially true in the case of SAR data because of the complexity in the interpretation of the measured signal, the same is also true for optical data when working in highly vegetated areas or when dealing with the retrieval of parameters related to the water content of soil/vegetation systems. In this paper, the authors demonstrate the capabilities of synergistic approaches by using polarimetric AIRSAR and Landsat TM data by means of a combined modeling approach, where the information content of each data type is explicitly separated into the parameters which are intrinsic to only one type of data and those which really provide the combined information potentially retrievable by means of data synergy