On coupling a regional ecosystem model with satellite derived parameters: case of a Sahelian grassland

The assessment of vegetation activity in the continental biosphere is possible using remote sensing techniques. However, its representation by remotely sensed empirically derived parameters forbids a satisfactory analysis of important climatic and physiological factors affecting vegetation activity. An alternative approach relies on the combined use of remote sensing spectral measurements with an ecosystem model which describes the relevant processes of the soil-vegetation-atmosphere system. After a brief description of the model developed for that purpose, and its validation, the paper gives a concise outlining of the first steps followed to perform the coupling of the model with remote sensing data