Heterogeneity and change of scale in models of remote sensing. Spatialization of multi-spectral models

The multi-spectral reflectances measured from the satellite lead to soil surface information through models. Since these models are defined and validated at local scale, where the soil surface is considered to be homogeneous, the use of the models with satellite multi-spectral reflectances as inputs will create a gap between the corresponding output and the average of the local in situ outputs. We study the basis of the gap between the outputs of the model applied to global measurements and the average of its local outputs. This general problem in remote sensing is stated and approached without any a priori assumption on the measured parameter with respect to change of scale, as is made for example, with the fractal assumption