The use of the ERS-1 scatterometer for global vegetation monitoring

This paper investigates the potential of ERS-1 Wind SCatterometer (WSC) data for global vegetation monitoring. Methods by which global backscatter images are generated from the scatterometer raw data are presented. This includes a discussion of the three aspects of averaging, temporal, spatial, and across incidence angle. A simple model was used to approximate the incidence angle dependence of the measurements. A year’s monthly images from January 95 to December 95 show clear seasonal patterns in the mean backscatter. These seasonal changes exhibit good agreement with the expected weather changes throughout the year. A semi-empirical modelling approach was used to relate the observed backscattering values to the physical parameters of the vegetation. This uses a modified version of the water cloud model, which accounts for the interaction between the vegetation layer and the underlying soil. Modelling of the backscatter would provide us with a means of relating it to global vegetation models, and ultimately validating those models.