Characteristics of fire-generated gas emission observed during a large peatland fire in 2009 at Kalimantan, Indonesia

• Gas emission ratios from a tropical peatland fire were evaluated.
• CO2-normalized emission ratio was calculated for CO, CH4, and N2O.
• Concentrations of CO and CH4 showed positive linear correlations with that of CO2.
• Molar ratio of gas emission was CO2:CO:CH4:N2O = 1.00:0.382:0.0261:0.000156.
• Emission of global warming potential was CO2:CH4:N2O = 1.00:0.237:0.0465.

To investigate the characteristics of gas emissions from a tropical peatland fire, ground-level measurement of fire-generated gases was conducted during a large fire event in Kalimantan, Indonesia in 2009. Concentrations of CO and CH4 showed positive linear correlations with that of CO2. The relationship between concentrations of N2O and CO2 were divided into two parts, suggesting the influence of additional N2O generation during sample storage. The CO2-normalized emission ratio was calculated for CO, CH4, and N2O. The molar ratio of these fire-generated gas emissions was summarized as CO2:CO:CH4:N2O = 1.00:0.382:0.0261:0.000156, whereas the emission ratio calculated on the global warming potential (GWP) basis was CO2:CH4:N2O = 1.00:0.237:0.0465. The GWP emission based on this ratio was 87.8–91.2% of a simple evaluation in which all carbon was assumed to be emitted as CO2. This is the first trial to evaluate the emission ratios of major greenhouse gases on the basis of ground-level observation during an actual tropical peatland fire.