Estimation of biomass burning emission of NO 2 and CO from 2019–2020 Australia fires based on satellite observations

[摘要] The bushfires that occurred in Australia in late 2019 and early 2020 were unprecedented in terms of their scale, intensity, and impacts. Usingnitrogen dioxide ( NO 2 ) and carbon monoxide (CO) data measured by the Tropospheric Monitoring Instrument (TROPOMI), together with fire countsand fire radiative power (FRP) from MODIS, we analyzed the temporal and spatial variation of NO 2 and CO  column densities over threeselected areas covering savanna and temperate forest vegetation. The Δ NO 2 / Δ CO emission ratio and emission factor werealso estimated. The Δ NO 2 / Δ CO emission ratio was found to be 1.57  ±  1.71 for temperate forest fire and rangedfrom 2.0  ±  2.36 to 2.6  ±  1.92 for savanna fire. For savanna and temperate forest fires, satellite-derived NO x emissionfactors were found to be 1.48 and 2.39  g kg −1 , respectively, whereas the CO emission factors are 107.39 and126.32  g kg −1 , respectively. This study demonstrates that the large-scale emission ratio from the TROPOMI satellite for differentbiomass burnings can help identify the relative contribution of smoldering and flaming activities in a large region and their impacts on theregional atmospheric composition and air quality. This method can be applied to study the emissions from other large fires, or even the burning offossil fuel in megacities, and their impact on air quality.

[学科分类] 医学（综合）