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Annual and diurnal African biomass burning temporal dynamics
G. Roberts, M. J. Wooster, and E. Lagoudakis
King's College London, Environmental Monitoring and Modeling Research Group, Department of Geography, Strand, London, WC2R 2LS, UK
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Abstract. Africa is the single largest continental source of biomass
burning emissions. Here we conduct the first analysis of one full year of
geostationary active fire detections and fire radiative power data recorded
over Africa at 15-min temporal resolution and a 3 km sampling distance
(at the sub-satellite point) by the SEVIRI imaging radiometer onboard the
Meteosat-8 satellite. We use these data to provide new insights into the
rates and totals of African open biomass burning, particularly into the
extremely strong seasonal and diurnal cycles that exist across the
continent. We find peak daily biomass combustion totals are 9 and 6 million
tonnes per day in the Northern and Southern Hemispheres respectively, and
total fuel consumption between February 2004 and January 2005 is at least 855 million
tonnes. Analysis is carried out with regard to fire pixel temporal
persistence, and we note that the majority of African fires are detected
only once in consecutive 15 min imaging slots, indicating the importance
of optimizing the fire pixel detection strategy performance. An
investigation of the variability of the diurnal fire cycle is carried out
with respect to 20 land cover types, and whilst differences are noted
between land covers, the diurnal characteristics for a given land cover type
are similar in both African hemispheres. We compare the FRP-derived biomass
combustion estimates to burned-areas, both at the scale of individual fires
and over the entire continent at a 1-degree spatial scale. Fuel consumption
estimates are found to be less than 2 kg/m2 for almost all land cover
types, and for savanna grasslands where literature values are commonly
reported the FRP-derived median fuel consumption estimate of 309 g/m2
appears reasonable. From mid-2008, geostationary FRP data of the type
presented here will become available to interested users continuously and in
near real-time from the EUMETSAT Land Surface Analysis Satellite
Applications Facility (LandSAF), allowing the types of analysis presented in
this paper to be undertaken on multi-year datasets where relationships
between climate variables, active fires and fuel consumption can be further
examined.
 The requested discussion paper has a corresponding peer-reviewed final revised
paper in the journal Biogeosciences (BG). You are
encouraged to refer to the final revised version. Final Revised Paper (BG) Discussion Paper (PDF, 1990 KB)
Citation: Roberts, G., Wooster, M. J., and Lagoudakis, E.: Annual and diurnal African biomass burning temporal dynamics, Biogeosciences Discuss., 5, 3623-3663, doi:10.5194/bgd-5-3623-2008, 2008. Bibtex EndNote Reference Manager XML
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