Monitoring land-cover changes in West Africa with SPOT Vegetation: impact of natural disasters in 1998-1999

A multi-temporal change-vector algorithm has been applied to SPOT Vegetatio n data of West Africa over two growing seasons. Change maps displaying the impact on surface attributes of natural disasters such as floods and drough ts were produced, based on different vegetation indices and compositing per iods. The accuracy assessed on the basis of independent data on natural dis asters, was high (76% correct for the NDVI-based map). This land-cover chan ge product provides important information to evaluate the spatial and tempo ral distribution of rapid changes in land surface attributes.