Regional analysis from data from heterogeneous pixels - Remote sensing of total dry matter production in the Senegalese Sahel

Nine predominantly cloud-free NOAA-7 advanced very high resolution radiometer images were obtained during a three-month period during the 1981 rainy season in the Sahel of Senegal. The 0.55-0.68 and 0.725-1.10-micron channels were used to form the normalized difference green leaf density vegetation index and the 11.5-12.5-micron channel was used as a cloud mask for each of the nine images. Changes in the normalized difference values among the various dates were closely associated with precipitation events. Six of the images spanning an eight-week period were used to generate a cumulative integrated index. Ground biomass samplings in the 30,000 sq km study area were used to assign total dry biomass classes to the cumulative index.