Monitoring seasonal vegetation dynamics in the Sahel with ERS wind scatterometer data

ERS-I wind-scatterometer data acquired over a saharo-sahelian region located in the Gourma, Mali during the period 1992-1995, are analysed Experimental observations show that σ°(45) temporal data display a marked seasonality associated with the development and senescence of annual grasses during the successive rainy seasons. The interpretation of the temporal σ° plots is performed with the assistance of a semi-empirical backscattering model combined with an ecosystem grassland model. The backscattering model is parameterised as a function of two surface parameters, namely the soil volumetric water content and the total biomass. The use of this simplified model allows the total biomass to be estimated with a 33% error.