A new method is used to generate spatial estimates of monthly averaged biomass burned area and spatial and temporal estimates of trace gas and aerosol emissions from open fires in southern Africa.
Global burned area data for the year 2000 (GBA2000) supplemented with the Along Track Scanning Radiometer (ATSR) fire count data are employed to quantify the area burned at 1-km resolution by using a fractional vegetation cover map derived from satellite observations. To account for the spatial heterogeneity in main types of vegetation within each 1-km grid cell, fuel load maps were developed from biomass density data sets for herbaceous and tree covered land together with fractional tree and vegetation cover maps. To represent the fire characteristics, land cover is classified into forests, woodlands, and grasslands, based on satellite-derived data sets for fractional tree cover. Combustion factors for each land cover type takes into account fuel composition, tree cover density, and the dryness of herbaceous vegetation. In addition, the emission factors (EF) are calculated; EF for grassland fires represent spatial and seasonal variations in fuel conditions using a modified combustion efficiency calculation.
This data set contains spatial and temporal estimates of trace gas and aerosol emissions from open fires in southern Africa for the following variables: acetic acid (CH3COOH); methanol (CH3OH); methane (CH4); carbon dioxide (CO2); carbon monoxide (CO); formaldehyde (HCHO); non-methane hydrocarbons (NMHC); and particulate matter less than 2.5 µm in diameter (PM2.5). Annual amounts of total area burned and CO2 emissions for southern Africa are compared to those from other authors.
Cite this data set as follows:
Ito, A., and J. E. Penner. 2004. SAFARI 2000 1-Degree Estimates of Burned Biomass, Area, and Emissions, 2000. Data set. Available on-line [http://daac.ornl.gov/] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/754.
Gregoire, J.-M., K. Tansey, and J. M. N. Silva. 2003. The GBA2000 initiative: Developing a global burned area database from SPOT-VEGETATION imagery. Int. J. Remote Sensing, 24: 1369-1376.
Hansen, M. C., R. S. DeFries, J. R. G. Townshend, M. Carroll, C. Dimiceli, and R. A. Sohlberg. 2003. Global percent tree cover at a spatial resolution of 500 meters: First results of the MODIS vegetation continuous fields algorithm. Earth Interactions, 7(10): 1-15.
Silva, J. M. N., J. M. C. Pereira, A. I. Cabral, A. C. L. Sa, M. J. P. Vasconcelos, B. Mota, and J.-M. Gregoire. 2003. An estimate of the area burned in southern Africa during the 2000 dry season using SPOT-VEGETATION satellite data. J. Geophys. Res., 108(D13), 8498, doi:10.1029/2002JD002320.
van der Werf, G. R., J. T. Randerson, G. J. Collatz, and L. Giglio. 2003. Carbon emissions from fires in tropical and subtropical ecosystems. Global Change Biol, 9(4): 547-562.
This data set contains estimates of trace gas and aerosol emissions from open fires in southern Africa for 8 separate data variables:
Acetic Acid (CH3COOH)
Methanol (CH3OH)
Methane (CH4)
Carbon Dioxide (CO2)
Carbon Monoxide (CO)
Formaldehyde (HCHO)
Non-Methane Hydrocarbons (NMHC)
Particulate Matter (less than 2.5 µm in diameter) (PM)
There are 3 different types of data files: monthly ASCII maps (.asc) and monthly ASCII map data files (.dat) for each variable for each modeled scenario; and a regional monthly emissions data file (.csv) which provides total monthly emissions estimates for each trace gas and PM2.5. The model runs four different "scenarios" (labeled "Sc1", "Sc2", "Sc3", and "Sc4"), each having a different set of model output files. These "scenarios" are described in detail in the "Fuel Load Model" section of the companion file.
The monthly ASCII scenario maps (.asc) are on a 1 degree grid, and have 74 columns and 36 rows, with space-delimited ASCII numbers. The monthly ASCII scenario data files (.dat) are the map data in column format (the first 74 values are all 0-1S and progress from 18W to 56E, then next 74 values are the next line of the map, etc.). The emissions data file (emission_totals.csv) is a comma-delimited ASCII file containing total emissions for the region by variable by month.
File naming conventions are as follows:
emi_scN_xxx_2000-08.asc is the monthly ASCII map for August 2000 (kg) (74x36 pixels)
emi_scN_xxx_2000-08.dat is the monthly ASCII data file for August 2000 (kg)
emi_scN_xxx_2000-09.asc is the monthly ASCII map for September 2000 (kg) (74x36 pixels)
emi_scN_xxx_2000-09.dat is the monthly ASCII data file for September 2000 (kg)
emission_totals.csv is the monthly totals for August & September 2000 (Tg)
where N is the scenario number (1-4) and xxx is one of the following variable abbreviations:
ch3cooh is acetic acid
ch3oh is methanol
ch4 is methane
co2 is carbon dioxide
co is carbon monoxide
hcho is formaldehyde
nmhc is non-methane hydrocarbons
pm is particulate matter less than 2.5 µm in diameter
Additional information about the analytical methods, data format, and results is found in the companion file: http://daac.ornl.gov/daacdata/safari2k/regional/one_deg_biomass/comp/one_degree_biomass_readme.pdf.
2004/7/28
2004/7/28
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