Emission of trace gases and aerosols from biomass burning – an updated assessment

Abstract

Since the publication of the compilation of biomass burning emission factors by Andreae and Merlet (2001), a large number of studies have greatly expanded the amount of available data on emissions from various types of biomass burning. Using essentially the same methodology as Andreae and Merlet (2001), this paper presents an updated compilation of emission factors. The data from over 370 published studies were critically evaluated and integrated into a consistent format. Several new categories of biomass burning were added, and the number of species for which emission data are presented was increased from 93 to 121. Where field data are still insufficient, estimates based on appropriate extrapolation techniques are proposed. For key species, the updated emission factors are compared with previously published values. Based on these emission factors and published global activity estimates, I have derived estimates of pyrogenic emissions for important species released by the various types of biomass burning.

Spaceborne Measurements of Formic and Acetic Acids: A Global View of the Regional Sources

“…Efficient removal from the atmospheric boundary layer via wet and dry deposition reduces their global lifetime to ∼2.3 and 3.2 days, respectively (Paulot et al, 2011); therefore, the abundance of both compounds drops off outside the source regions. Over the biomass burning areas, the ratios are similarly close to 1, although higher fire emission factors for CH 3 COOH than for HCOOH are reported in the literature (Akagi et al, 2011;Andreae, 2019). While we cannot rule out potential retrieval biases, another explanation is a rapid secondary HCOOH formation, as suggested by space-based pyrogenic HCOOH enhancement ratios that are significantly higher than expected (Chaliyakunnel et al, 2016;Pommier et al, 2017), and which would not be present to the same degree for CH 3 COOH.…”

Understanding nighttime methane signals at the Amazon Tall Tower Observatory (ATTO)

“…Following the same approach as in Fig 12, the BC:CO in Fig 13 suggests a more clear fire signal for the ESE and SSE wind directions. Note that the time period used in this plot differs form that in Fig 12 and contains fewer data points, yet some of those points fall on the reference slopes of Andreae (2019). In general terms, even though fire signals are measured at ATTO during nighttime for positive CH 4 gradients as suggested by Fig 13, the nighttime CH 4 enhancements at 79 m are not fully explained by combustion.…”

“…The timing of the biomass burning season coincides with the dry season in the Amazon region (Gatti et al, 2014;van der Laan-Luijkx et al, 2015;Aragão et al, 2018), thus one could think that CH 4 from combustion is responsible for the positive gradients presented here. During biomass burning, in particular in the case of incomplete combustion, CH 4 is co-emitted 10 together with carbon monoxide (CO), amongst other gases and particles (Akagi et al, 2011;Kirschke et al, 2013;Andreae, 2019). Because CO is emitted in large quantities and due to its low background mixing ratio, this species is considered a good proxy for biomass burning and it can be used as a reference to get an idea of enhancement ratios due to fire emissions.…”

“…However, these data points represent only 10% of the data shown. Moreover, biomass burning typically produces CH 4 in a certain emission ratio to CO, dependent on the fuel type Andreae and Merlet (2001); Andreae (2019). These reference ratios are plotted as slopes in Fig.…”

Historical (1700-2012) global multi-model estimates of the fire emissions from the Fire Modeling Intercomparison Project (FireMIP)

“…The EFs used in this study (Table 3) are based on Andreae and Merlet (2001), with updates from field and laboratory studies over various land cover types published during 2001-2018 (Andreae, 2019). All FireMIP model simulations used the same EFs from Table 3.…”