Rapid transformation of wildfire emissions to harmful background aerosol

npj Climate and Atmospheric Science, Journal Year: 2023, Volume and Issue: 6(1)

Published: Dec. 21, 2023

Abstract Wildfires are a significant source of organic aerosol during summer, with major impacts on air quality and climate. However, studies in Europe suggest surprisingly low (less than 10%) contribution biomass burning to average summertime fine particulate matter levels. In this study we combine field measurements atmospheric chemical transport modeling, demonstrate that the wildfires particle levels summer is seriously underestimated. Our work suggests corresponding has been underestimated by factor 4–7 were responsible for approximately half total OA July 2022. This discrepancy previous due rapid physicochemical transformation these emissions secondary oxidized an accompanying loss its fingerprints. These reactions lead regionally distributed background fraction health-related caused particles probably other continents. adverse health effects can occur hundreds or even thousands kilometers away from fires. We estimate wildfire 15–22% deaths exposure summer.

Language: Английский

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Sources of wintertime PM2.5 at a major city in an Alpine Valley: The role of atmospheric dispersion and inversion dynamics

Atmospheric Environment, Journal Year: 2024, Volume and Issue: 330, P. 120556 - 120556

Published: April 30, 2024

Urban areas in mountain environments are generally located on valley floors surrounded by slopes, where orography drives peculiar meteorology and atmospheric circulation. Also, persistent inversion dynamics may occur strongly affecting air pollution. This study characterizes the PM2.5 pollution a major city an Alpine (Belluno, Northeastern Italy) during cold season (Autumn-Winter). Major particulate species (elemental organic carbon, inorganic ions) minor/trace elements conventionally used as tracers for source apportionment were analyzed, including oxalate specific PM2.5-bound biomass burning (K+, levoglucosan, mannosan, galactosan) primary biogenic aerosol (arabitol, mannitol, glucose). sources identified through positive matrix factorization series of post-processing tools. Results indicate that burning, mostly emitted residential wood combustion domestic heating, is (52% mass concentration), followed secondary (21%), (20%), traffic (4%), dust resuspension (3%). The contributions assessed accounting local meteorology. Insights into dispersion or buildup then investigated normalization. In addition, possible effects thermal events evaluated assessing strength from temperature profiles measured at multiple weather stations different elevations with respect to contributions. Beyond identification those emission requiring further mitigation actions, this also analyses potential methodologies applied can be easily adopted other successful management quality.

Language: Английский

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Evolution of atmospheric high-molecular-weight Organonitrates (HMW ONs) in urban Yangtze River Delta (YRD), China

npj Climate and Atmospheric Science, Journal Year: 2025, Volume and Issue: 8(1)

Published: Feb. 14, 2025

Language: Английский

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Characterization and dark oxidation of the emissions of a pellet stove

Environmental Science Atmospheres, Journal Year: 2023, Volume and Issue: 3(9), P. 1319 - 1334

Published: Jan. 1, 2023

Pellet combustion in residential heating stoves has increased globally during the last decade. Despite their high efficiency, widespread use of pellet is expected to adversely impact air quality. The atmospheric aging emissions received even less attention, focusing mainly on daytime conditions, while degree which undergo night-time as well role relative humidity remain poorly understood. In this study, environmental simulation chamber experiments were performed characterize fresh and aged organic aerosol (OA) emitted by a stove. stove PM1 (particulate matter with an aerodynamic diameter than 1 μm) consisted OA (93 ± 4%, mean standard deviation) black carbon (5 3%). primary (POA) oxygen-to-carbon ratio (O : C) was 0.58 0.04, higher that logwood emissions. at concentration 70 μg m-3 (after dilution equilibration chamber) semi-volatile (68%), low extremely volatility (16%) intermediate-volatility compounds. oxidation under dark conditions investigated injecting nitrogen dioxide (NO2) ozone (O3) into chamber, different (10-80%) (RH) levels. all secondary (SOA) formation observed, increasing levels after few hours exposure NO3 radicals. change composition extent depended RH. For RH, SOA mass formed up 30% initial OA, accompanied moderate both O C (7-8% increase) spectrum. Aging RH (60-80%) led more oxygenated (increase 11-18%), but only minor (1-10%) increase mass. indicates importance heterogeneous aqueous reactions system, oxidize original relatively small net These results show can chemically evolve photochemical activity (e.g. wintertime period) important enhancement certain conditions.

Language: Английский

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Physicochemical Characterization of Religious Burning Aerosols in Lhasa on the Qinghai‐Tibet Plateau

Journal of Geophysical Research Atmospheres, Journal Year: 2024, Volume and Issue: 129(16)

Published: Aug. 21, 2024

Abstract Religious burning (RB) has been identified as a major source of atmospheric aerosols on the Qinghai‐Tibet Plateau. However, there is limited understanding detailed chemical composition, size distribution, and optical properties RB in this region. To characterize these important aerosol properties, ambient PM 2.5 resolved from emissions Lhasa were collected during summer 2019. Organic functional group (OFG) inorganic ion composition was measured using Fourier transform infrared spectroscopy chromatography, respectively. The dominated by organic components, with OFG concentrations significantly higher religious events, reflecting substantial impact local air quality. characterized high fractions alkane (34%), hydroxyl (29%), carboxylic acid (13%) groups, peak mass accumulation mode (0.56–1.00 μm). abundance distribution pattern suggested that formed volatilization fuel materials followed unaltered condensation, process may be unique to low‐temperature, low‐oxygen scattered burners at temples. absorption coefficient showed similar but Ångström exponent displayed lowest value 0.56–1.00 μm mode. This specific aligned fraction acids mirrored proportion alkanes, suggesting smaller larger particles enriched substances have light‐absorbing capabilities.

Language: Английский

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Observing Super-Coarse Carbonaceous Aerosol Particles Containing Chloride in a Tropical Savanna Climate at an Agro-Forest Site in Thailand

Published: Jan. 1, 2024

This study aimed to investigate the sources and characteristics of super-coarse carbonaceous aerosol particles containing chloride in a tropical savanna climate. Aerosol samples were collected from an agro-forest site Thailand during dry season analyzed using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared (FTIR) spectroscopy. By analyzing morphology elemental compositions individual applying positive matrix factorization (PMF) analysis, their potential have been elucidated. The findings revealed two possible particles: mixed biomass burning smoke with inorganic salts (probably saline soil, sea salt), halophilic fungal spores. Functional group analysis FTIR indicated presence compounds associated clay minerals, influenced by prevailing NE SE winds, respectively. Recommendations for further research include continued monitoring, correlation meteorological parameters, utilization transmission (TEM) techniques detailed visualization confirmation sources.

Language: Английский

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Real-time chemical characterization of primary and aged biomass burning aerosols derived from Sub-Saharan African biomass fuels in smoldering fires

Environmental Science Atmospheres, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

The influence of biomass burning (BB)-derived organic aerosol (OA) emissions on solar radiation

Language: Английский

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