Main conclusions of the international colloquium on “Spectral Signatures of Objects in Remote Sensing”

The colloquium held in Avignon (France) from September 8th to 11th 1981 within the framework of the International Society for Photogrammetry and Remote Sensing, was the first international meeting to be given over exclusively to the question of spectral signatures.A number of general conclusions can be drawn from the working sessions :- present day knowledge is much more advanced concerning visible and near infrared than for thermal infrared and (more particularly) micro-waves ;- irrespective of the spectral range studied, radiometric signals reflected or emitted by a vegetative canopy are closely related to its geometry ;- the combination of the vertical and oblique views of a given zone should provide additional data leading to finer discrimination between different crops at any given time ;- by using polarization of light, it should be possible to identify certain phenological stages.