Impact of Environmental Conditions on Secondary Organic Aerosol Production from Photosensitized Humic Acid

This work explores the effect of environmental conditions on the photodegradation rates of atmospherically relevant, photolabile, organic molecules embedded in a film of viscous secondary organic material (SOM).

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Secondary organic aerosol formation from p-dichlorobenzene under indoor environmental conditions

Building and Environment ◽

10.1016/j.buildenv.2020.106758 ◽

2020 ◽

Vol 174 ◽

pp. 106758 ◽

Cited By ~ 1

Author(s):

Sota Komae ◽

Kazuhiko Sekiguchi ◽

Megumi Suzuki ◽

Ryoichi Nakayama ◽

Norikazu Namiki ◽

...

Keyword(s):

Environmental Conditions ◽

Secondary Organic Aerosol ◽

Organic Aerosol ◽

Aerosol Formation ◽

Secondary Organic Aerosol Formation

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Exploration of the influence of environmental conditions on secondary organic aerosol formation and organic species properties using explicit simulations: development of the VBS-GECKO parameterization

10.5194/acp-2018-233 ◽

2018 ◽

Author(s):

Victor Lannuque ◽

Marie Camredon ◽

Florian Couvidat ◽

Alma Hodzic ◽

Richard Valorso ◽

...

Keyword(s):

Environmental Conditions ◽

Secondary Organic Aerosol ◽

Optimization Procedure ◽

Organic Aerosol ◽

Basis Set ◽

Vaporization Enthalpy ◽

Aerosol Formation ◽

Additional Information ◽

Precursor Structure ◽

Chemical Conditions

Abstract. Atmospheric chambers have been widely used to study secondary organic aerosol (SOA) properties and formation from various precursors under different controlled environmental conditions and to develop parameterization to represent SOA formation in chemical-transport models (CTM). Chamber experiments are however limited in number, performed under conditions that differ from the atmosphere and can be subject to potential artifacts from chamber walls. Here the Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) modelling tool has been used in a box model under various environmental conditions to (i) explore the sensitivity of SOA formation and properties to changes on physical and chemical conditions and (ii) to develop a Volatility Basis Set type parameterization. The set of parent hydrocarbons includes n-alkanes and 1-alkenes with 10, 14, 18, 22, and 26 carbon atoms, α-pinene, β-pinene and limonene, benzene, toluene, o-xylene, m-xylene and p-xylene. Simulated SOA yields and their dependences on the precursor structure, organic aerosol load, temperature and NOx levels are consistent with the literature. GECKO-A was used to explore the distribution of molar mass, vaporization enthalpy, OH reaction rate and Henry's law coefficient of the millions of secondary organic compounds formed during the oxidation of the different precursors and under various conditions. From these explicit simulations, a VBS-GECKO parameterization designed to be implemented in 3D air quality models has been tuned to represent SOA formation from the 18 precursors using GECKO-A as a reference. Its evaluation shows that VBS-GECKO captures the dynamic of SOA formation for a large range of conditions with a mean relative error on organic aerosol mass temporal evolution lesser than 20 % compared to explicit simulations. The optimization procedure has been automated to facilitate the update of the VBS-GECKO on the basis of the future GECKO-A versions, its extension to other precursors and/or its modification to carry additional information.

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Using explicit mechanisms of Secondary Organic Aerosol (SOA) formation and evolution to extrapolate chamber studies to the atmosphere

10.5194/egusphere-egu2020-3415 ◽

2020 ◽

Author(s):

Joel A Thornton ◽

John Shilling ◽

Havala Pye ◽

Emma D'Ambro ◽

Maria Zawadowicz ◽

...

Keyword(s):

Environmental Conditions ◽

Secondary Organic Aerosol ◽

Field Studies ◽

Organic Aerosol ◽

Pressure Lowering ◽

Formation And Evolution ◽

Chemical Conditions ◽

Chamber Studies ◽

Multi Phase ◽

Phase Chemistry

<p>&#160;</p><p>The applicability of chamber-derived Secondary Organic Aerosol (SOA) yields to the atmosphere remains a key uncertainty in modeling SOA. The chemical and environmental conditions achieved in chambers are narrower than and often significantly biased from those experienced in the atmosphere. We present results from applying explicit chemical mechanisms in a dynamic gas-particle partitioning model (FOAM-WAM) to simulate SOA formation and evolution from a range of chamber experiments involving isoprene and monoterpenes. We focus on how such comparisons can highlight the applicability, or the lack thereof, of derived SOA yields, extrapolate measured SOA yields to more complex chemical or environmental conditions, and identify key gaps in chemical or physical mechanisms and thus feedback on chamber experiment design and earth system model parameterizations. In particular, we show that current mechanisms of low-NOx isoprene and a-pinene oxidation that incorporate RO2 H-shift reactions can adequately explain corresponding fresh SOA without the need for substantial vapor-pressure lowering accretion chemistry, while substantial particle-phase photo-chemistry is required to explain the dynamic evolution of SOA characteristics (volatility, O/C ratios, etc)observed in chambers at longer aging times. We find that chemical conditions, such as absolute concentrations, are as important as vapor wall loss, or even more so, at perturbing SOA yields from realistic values. Consistent with recent field studies but in contrast to previous chamber studies, our modeling predicts that low-NOx isoprene oxidation is unlikely to produce significant SOA in warm boundary layers, except through isoprene epoxy-diol multi-phase chemistry. Current mechanisms are unable to reproduce the non-linear response of isoprene-derived photochemical SOA with NOx observed in multiple chambers, suggesting a potentially important missing mechanism of volatility reduction at intermediate NOx concentrations in that system.&#160;</p>

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Exploration of the influence of environmental conditions on secondary organic aerosol formation and organic species properties using explicit simulations: development of the VBS-GECKO parameterization

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-13411-2018 ◽

2018 ◽

Vol 18 (18) ◽

pp. 13411-13428 ◽

Cited By ~ 6

Author(s):

Victor Lannuque ◽

Marie Camredon ◽

Florian Couvidat ◽

Alma Hodzic ◽

Richard Valorso ◽

...

Keyword(s):

Environmental Conditions ◽

Secondary Organic Aerosol ◽

Optimization Procedure ◽

Organic Aerosol ◽

Basis Set ◽

Vaporization Enthalpy ◽

Aerosol Formation ◽

Additional Information ◽

Precursor Structure ◽

Chemical Conditions

Abstract. Atmospheric chambers have been widely used to study secondary organic aerosol (SOA) properties and formation from various precursors under different controlled environmental conditions and to develop parameterization to represent SOA formation in chemical transport models (CTMs). Chamber experiments are however limited in number, performed under conditions that differ from the atmosphere and can be subject to potential artefacts from chamber walls. Here, the Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) modelling tool has been used in a box model under various environmental conditions to (i) explore the sensitivity of SOA formation and properties to changes on physical and chemical conditions and (ii) develop a volatility basis set (VBS)-type parameterization. The set of parent hydrocarbons includes n-alkanes and 1-alkenes with 10, 14, 18, 22 and 26 carbon atoms, α-pinene, β-pinene and limonene, benzene, toluene, o-xylene, m-xylene and p-xylene. Simulated SOA yields and their dependences on the precursor structure, organic aerosol load, temperature and NOx levels are consistent with the literature. GECKO-A was used to explore the distribution of molar mass, vaporization enthalpy, OH reaction rate and Henry's law coefficient of the millions of secondary organic compounds formed during the oxidation of the different precursors and under various conditions. From these explicit simulations, a VBS-GECKO parameterization designed to be implemented in 3-D air quality models has been tuned to represent SOA formation from the 18 precursors using GECKO-A as a reference. In evaluating the ability of VBS-GECKO to capture the temporal evolution of SOA mass, the mean relative error is less than 20 % compared to GECKO-A. The optimization procedure has been automated to facilitate the update of the VBS-GECKO on the basis of the future GECKO-A versions, its extension to other precursors and/or its modification to carry additional information.

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Secondary organic aerosol formation from biomass burning emissions

10.5194/acp-2019-326 ◽

2019 ◽

Cited By ~ 2

Author(s):

Christopher Y. Lim ◽

David H. Hagan ◽

Matthew M. Coggon ◽

Abigail R. Koss ◽

Kanako Sekimoto ◽

...

Keyword(s):

Biomass Burning ◽

Secondary Organic Aerosol ◽

Total Concentration ◽

Organic Aerosol ◽

Oh Radicals ◽

Aerosol Formation ◽

Atmospheric Aging ◽

Aerosol Mass ◽

Photochemical Aging ◽

Organic Gases

Abstract. Biomass burning is an important source of aerosol and trace gases to the atmosphere, but how these emissions change chemically during their lifetimes is not fully understood. As part of the Fire Influence on Regional and Global Environments Experiment (FIREX 2016), we investigated the effect of photochemical aging on biomass burning organic aerosol (BBOA), with a focus on fuels from the western United States. Emissions were sampled into a small (150 L) environmental chamber and photochemically aged via the addition of ozone and irradiation by 254 nm light. While some fraction of species undergoes photolysis, the vast majority of aging occurs via reaction with OH radicals, with total OH exposures corresponding to the equivalent of up to 10 days of atmospheric oxidation. For all fuels burned, large and rapid changes are seen in the ensemble chemical composition of BBOA, as measured by an aerosol mass spectrometer (AMS). Secondary organic aerosol (SOA) formation is seen for all aging experiments and continues to grow with increasing OH exposure, but the magnitude of the SOA formation is highly variable between experiments. This variability can be explained well by a combination of experiment-to-experiment differences in OH exposure and the total concentration of non-methane organic gases (NMOGs) in the chamber before oxidation, measured by PTR-ToF-MS (r2 values from 0.64 to 0.83). From this relationship, we calculate the fraction of carbon from biomass burning NMOGs that is converted to SOA as a function of equivalent atmospheric aging time, with carbon yields ranging from 24 ± 4 % after 6 hours to 56 ± 9 % after 4 days.

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Aging of atmospheric aerosols and the role of iron in catalyzing brown carbon formation

Environmental Science: Atmospheres ◽

10.1039/d1ea00038a ◽

2021 ◽

Author(s):

Hind A. A. Al-Abadleh

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Atmospheric Aerosols ◽

Secondary Organic Aerosol ◽

Organic Aerosol ◽

Atmospheric Oxidation ◽

Carbon Formation ◽

Brown Carbon ◽

Volatile Organic

Extensive research has been done on the processes that lead to the formation of secondary organic aerosol (SOA) including atmospheric oxidation of volatile organic compounds (VOCs) from biogenic and anthropogenic...

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