Modelling the impact of vegetation fires, detected from NOAA-AVHRR data, on tropospheric chemistry in tropical Africa

Burned biomass, gas and aerosol emissions for the African continent were estimated using information on active fires whose spatial distribution was derived from NOAA-AVHRR HRPT (High Resolution Picture Trasmission 1.1 km resolution) and GAC (Global Area Coverage 4.5 km resolution) imagery. AVHRR-GAC images covering a four year period (November 1984-October 1988) provided information on seasonality and inter-annual variability of fire activity while AVHRR-HRPT were used for quantitative assessment purposes for the period November 1992-October 1993. Above-ground biomass density, burning efficiency and emission factors for each vegetation type were retrieved from the literature. We estimated that 1360.45 Tg of biomass burned in 1992-93. The ecosystem mostly affected by vegetation fires was the Guinean Savanna located in the Northern hemisphere of the African continent. Results derived using the multi-annual data set of AVHRR-GAC images showed a high inter-annual variability for the estimates produced.