Aging of Atmospheric Brown Carbon Aerosol

ACS Earth and Space Chemistry, Journal Year: 2021, Volume and Issue: 5(4), P. 722 - 748

Published: April 5, 2021

Emitted by numerous primary sources and formed secondary sources, atmospheric brown carbon (BrC) aerosol is chemically complex. As BrC ages in the atmosphere via a variety of chemical physical processes, its composition optical properties change significantly, altering impacts on climate. Research past decade has considerably expanded our understanding reactions both gas condensed phases. We review these recent advances aging chemistry with focus phase leading to formation, aqueous in-cloud particle reactions. Connections are made between single component proxies more complex mixtures as well laboratory field measurements chemistry. General conclusions that can darken particles over short time scales hours close source considerable photobleaching oxidative whitening will occur when day or removed from source.

Language: Английский

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Climate Forcing and Trends of Organic Aerosols in the Community Earth System Model (CESM2)

Journal of Advances in Modeling Earth Systems, Journal Year: 2019, Volume and Issue: 11(12), P. 4323 - 4351

Published: Dec. 1, 2019

Abstract The Community Earth System Model version 2 (CESM2) includes three main atmospheric configurations: the Atmosphere 6 (CAM6) with simplified chemistry and a organic aerosol (OA) scheme, CAM6 comprehensive tropospheric stratospheric representation (CAM6‐chem), Whole Climate (WACCM6). Both, CAM6‐chem WACCM6 include more secondary aerosols (SOA) approach using Volatility Basis Set (VBS) scheme prognostic aerosols. This paper describes different OA schemes available in configurations of CESM2 discusses differences burden resulting climate forcings. Derived trends differ due to formation approaches. Regional Aerosol Optical Depth larger values occur over SOA source regions. Stronger increasing between 1960 2015 compared are biogenic emissions aligned surface temperatures. Using further leads improved comparisons aircraft observations ≈143 Tg/yr. We use identify contributions from biogenic, fossil fuel, biomass burning emissions, quantify amounts these sources. Increasing result Biogenic at least two thirds total burden. In addition, fuel become important, largest Southeast Asia. estimated anthropogenic forcing for 1995–2010 conditions is −0.43 W/m , mostly direct effect.

Language: Английский

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Oxygenated Aromatic Compounds are Important Precursors of Secondary Organic Aerosol in Biomass-Burning Emissions

Environmental Science & Technology, Journal Year: 2020, Volume and Issue: 54(14), P. 8568 - 8579

Published: June 19, 2020

Biomass burning is the largest combustion-related source of volatile organic compounds (VOCs) to atmosphere. We describe development a state-of-the-science model simulate photochemical formation secondary aerosol (SOA) from biomass-burning emissions observed in dry (RH <20%) environmental chamber experiments. The modeling supported by (i) new oxidation measurements, (ii) detailed concurrent measurements SOA precursors emissions, and (iii) parameters for heterocyclic oxygenated aromatic based on historical find that compounds, including phenols methoxyphenols, account slightly less than 60% formed help our explain variability mass (R2 = 0.68) O/C 0.69) enhancement ratios across 11 Despite abundant included furans contribute ∼20% total SOA. use pyrolysis-temperature-based or averaged emission profiles represent precursors, rather those specific each fire, provide similar results within 20%. Our findings demonstrate necessity accounting aromatics their chemical mechanisms.

Language: Английский

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Rapid dark aging of biomass burning as an overlooked source of oxidized organic aerosol

Proceedings of the National Academy of Sciences, Journal Year: 2020, Volume and Issue: 117(52), P. 33028 - 33033

Published: Dec. 14, 2020

Significance To quantify the full implications of biomass burning emissions on atmosphere, it is essential to accurately represent emission plume after has undergone chemical aging in atmosphere. Atmospheric models typically consider predominant pathway take place presence sunlight (via OH radical); however, this mechanism leads consistent underpredictions oxidized organic aerosol wintertime urban areas. Here, we show, through a combination laboratory experiments, ambient field measurements, and transport modeling, that plumes exposed NO 2 O 3 age rapidly without requiring any sunlight, thus providing an overlooked source previously not accounted for models.

Language: Английский

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Ozone chemistry in western U.S. wildfire plumes

Science Advances, Journal Year: 2021, Volume and Issue: 7(50)

Published: Dec. 8, 2021

Wildfires are a substantial but poorly quantified source of tropospheric ozone (O3). Here, to investigate the highly variable O3 chemistry in wildfire plumes, we exploit situ chemical characterization western wildfires during FIREX-AQ flight campaign and show that production can be predicted as function experimentally constrained OH exposure, volatile organic compound (VOC) reactivity, fate peroxy radicals. The exhibits rapid transition regimes. Within few daylight hours, formation substantially slows is largely limited by abundance nitrogen oxides (NOx). This finding supports previous observations enhanced when VOC-rich smoke mixes into NOx-rich urban thereby deteriorating air quality. Last, relate underlying fire characteristics, enabling more accurate representation atmospheric models used study quality predict climate.

Language: Английский

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A review of aerosol chemistry in Asia: insights from aerosol mass spectrometer measurements

Environmental Science Processes & Impacts, Journal Year: 2020, Volume and Issue: 22(8), P. 1616 - 1653

Published: Jan. 1, 2020

Aerosol mass spectrometer has been widely deployed in Asia for real-time characterization of aerosol chemistry, and significantly improved our understanding the sources, properties, formation processes aerosols a complex environment.

Language: Английский

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On the stratospheric chemistry of midlatitude wildfire smoke

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(10)

Published: March 1, 2022

SignificanceLarge wildfires have been observed to inject smoke into the stratosphere, raising questions about their potential affect stratospheric ozone layer that protects life on Earth from biologically damaging ultraviolet radiation. Multiple observations of aerosol and NO2 concentrations three independent satellite instruments are used here together with model calculations identify decreases in following major Australian 2019 through 2020 wildfires. The data confirm important chemistry did occur particle surfaces. behavior increasing is a marker for surface contributes midlatitude depletion. results indicate wildfire activity warming world may slow recovery layer.

Language: Английский

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Ice‐Nucleating Particles That Impact Clouds and Climate: Observational and Modeling Research Needs

Reviews of Geophysics, Journal Year: 2022, Volume and Issue: 60(2)

Published: April 21, 2022

Abstract Atmospheric ice‐nucleating particles (INPs) play a critical role in cloud freezing processes, with important implications for precipitation formation and radiative properties, thus weather climate. Additionally, INP emissions respond to changes the Earth System climate, example, desertification, agricultural practices, fires, therefore may introduce climate feedbacks that are still poorly understood. As knowledge of nature origins INPs has advanced, regional global weather, system models have increasingly begun link ice processes model‐simulated aerosol abundance types. While these recent advances exciting, coupling simulated also makes physics simulations susceptible uncertainties simulation INPs, which constrained by observations. Advancing predictability reasonable spatiotemporal resolution will require an increased focus on research bridges measurement modeling communities. This review summarizes current state identifies gaps from both observational perspectives. In particular, we emphasize needs two key areas: (a) closure between quantities (b) skillful within existing models. We discuss various particle types briefly challenges faced understanding impacts present‐day Finally, identify priority directions observations improve their interactions System.

Language: Английский

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Fire Influence on Regional to Global Environments and Air Quality (FIREX‐AQ)

Journal of Geophysical Research Atmospheres, Journal Year: 2022, Volume and Issue: 128(2)

Published: Dec. 30, 2022

Abstract The NOAA/NASA Fire Influence on Regional to Global Environments and Air Quality (FIREX‐AQ) experiment was a multi‐agency, inter‐disciplinary research effort to: (a) obtain detailed measurements of trace gas aerosol emissions from wildfires prescribed fires using aircraft, satellites ground‐based instruments, (b) make extensive suborbital remote sensing fire dynamics, (c) assess local, regional, global modeling fires, (d) strengthen connections observables the ground such as fuels fuel consumption satellite products burned area radiative power. From Boise, ID western were studied with NASA DC‐8 two NOAA Twin Otter aircraft. high‐altitude ER‐2 deployed Palmdale, CA observe some these in conjunction overpasses other Further conducted three mobile laboratories sites, 17 different forecast analyses for fire, air quality climate implications. Salina, KS investigated 87 smaller Southeast in‐situ data collection. Sampling by all platforms designed measure gases aerosols multiple transects capture chemical transformation perform observations smoke plumes under day night conditions. linked consumed power orbital collected during overflights sampling fuels.

Language: Английский

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Formation of secondary organic aerosol from wildfire emissions enhanced by long-time ageing

Nature Geoscience, Journal Year: 2024, Volume and Issue: 17(2), P. 124 - 129

Published: Jan. 9, 2024

Language: Английский

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