Quantifying the Impact of Biomass Burning Emissions on Major Inorganic Aerosols and Their Precursors in the U.S.

Abstract

The primary sources for inorganic aerosols from biomass burning are rather negligible, but they are predominantly formed chemically following emission of their precursors (e.g., SO2, NH3, HOx, and NOx). The biomass burning contributions to some of the precursors can be considerable. Accordingly, we quantify the impact of the emissions on major inorganic aerosols in April–October 2012–2014 using a regional model simulation verified by extensive surface observations throughout the U.S. Simulated CO enhancements on an hourly basis are used to classify the U.S. into weak‐moderate (5 < COBiomass‐COBase < 20 ppbv) and strongly impacted periods (COBiomass‐COBase > 20 ppbv). This separation not only facilitates the identification of the spatial frequency of the impact but also helps to filter out nonimpacted periods, enabling us to focus on long‐term contributions. Despite the nonlinear responses of several trace gases to emissions, we observe increases (weak‐moderate and strong) in daily surface SO42− (1.16 ± 0.32 and 6.57 ± 4.65 nmol/m3), NO3− (0.36 ± 0.63, 4.70 ± 7.05 nmol/m3), and NH4+ (2.70 ± 0.92 and 17.82 ± 15.17 nmol/m3) on a national scale. These primarily resulted from (i) increases in daily surface SO2 (0.02 ± 0.01 and 0.10 ± 0.07 ppbv), afternoon OH (1.28 ± 4.24 and 12.82 ± 23.76 ppqv), and H2O2 (0.06 ± 0.02 and 0.10 ± 0.08 ppbv), which may have accelerated the conversion of S(IV) to S(VI), and (ii) increases in daily surface NH3 (1.08 ± 0.73 and 8.61 ± 7.73 nmol/m3) and HNO3 (1.44 ± 0.48 and 7.15 ± 4.25 nmol/m3), which could have produced more particle‐phase NH4NO3. In the West, where atmospheric moisture is limited, enhanced SO42− leaves less available water for NH4NO3 to become ions. Our results suggest that the major inorganic aerosol enhancement (mass) can reach to 23% of that of the carbonaceous aerosols.

A Decadal Climatology of Chemical, Physical, and Optical Properties of Ambient Smoke in the Western and Southeastern United States

“…Souri et al (2017) showed that biomass burning emitted negligible particulate nitrate but considerable amounts of gaseous precursors (NO x ). Souri et al (2017) showed that biomass burning emitted negligible particulate nitrate but considerable amounts of gaseous precursors (NO x ).…”

“…We also find that nitrate and sulfate concentrations are increased on smoky days. Souri et al (2017) showed that biomass burning emitted negligible particulate nitrate but considerable amounts of gaseous precursors (NO x ). Their work demonstrated that the formation of aerosol-phase nitrate particles was mainly from the conversion of NO x .…”

Isotopic constraints on the atmospheric sources and formation of nitrogenous species in clouds influenced by biomass burning

“…As for NH 3 , over 90 % of the NH 3 emissions in terrestrial ecosystems originate from agricultural production, such as livestock breeding and NH 3 -based fertilizer application (Paulot and Jacobs, 2014; Kang et al, 2016;Reis et al, 2009;Bouwman et al, 1997;Heald et al, 2012;Balasubramanian et al, 2015;Huang et al, 2011). In the urban atmosphere, recent studies suggest that nonagricultural activities like wastewater discharge (Zhang et al, 2017), coal burning (Li et al, 2016a), solid waste (Reche et al, 2012), on-road traffic (Suarez-Bertoa et al, 2014), and green spaces (Teng et al, 2017) also contribute to NH 3 emissions. In reactions with H 2 SO 4 and HNO 3 , NH 3 contributes to the formation of NH + 4 salts, which typically make up from 20 % to 80 % of fine particles (PM 2.5 ) in the atmosphere (Seinfeld and Pandis, 2012).…”

“…Biomass burning (BB) is an important source of N in the atmosphere (Lobert et al, 1990;Souri et al, 2017). During the harvest or hot season of eastern China, agricultural BB frequently occurs and modifies the concentration and composition of aerosols in the atmosphere Zhang and Cao, 2015).…”

Isotopic Constraints on the Atmospheric Sources and Formation of Nitrogenous Species in Biomass-Burning-Influenced Clouds

“…Biomass burning (BB) is an important source of N in the atmosphere (Lobert et al, 1990;Souri et al, 2017). During the harvest/hot season of eastern China, agricultural BB frequently occurs and modifies the concentration and composition of aerosols in the atmosphere (Chen et al,70 2017; Zhang and Cao, 2015).…”