The development of a vulnerability index for the evaluation of environmental changes in north-western Namibia is a central research topic within the interdisciplinary research project ACACIA (Arid Climate Adaptation and Cultural Innovation in Africa). The calculation of aboveground phyto-mass (= biomass) and its seasonal productivity by using a mesoscale biosphere model based on satellite data is of specific interest. The research area, Kaokoveld (north-western Namibia), is characterised by a strong hydro-climatic gradient with an annual precipitation range from 380mm/a in the north-eastern part of the research area to 50 mm/a at the border of the Namib Desert.