Formation and transport of oxidized reactive nitrogen, ozone, and secondary organic aerosol in Tokyo

Abstract. The reaction of α-pinene with NO3 is an important sink of both α-pinene and NO3 at night in regions with mixed biogenic and anthropogenic emissions; however, there is debate on its importance for secondary organic aerosol (SOA) and reactive nitrogen budgets in the atmosphere. Previous experimental studies have generally observed low or zero SOA formation, often due to excessive [NO3] conditions. Here, we characterize the SOA and organic nitrogen formation from α-pinene + NO3 as a function of nitrooxy peroxy (nRO2) radical fates with HO2, NO, NO3, and RO2 in an atmospheric chamber. We show that SOA yields are not small when the nRO2 fate distribution in the chamber mimics that in the atmosphere, and the formation of pinene nitrooxy hydroperoxide (PNP) and related organonitrates in the ambient can be reproduced. Nearly all SOA from α-pinene + NO3 chemistry derives from the nRO2 + nRO2 pathway, which alone has an SOA mass yield of 65 (±9) %. Molecular composition analysis shows that particulate nitrates are a large (60–70 %) portion of the SOA, and that dimer formation is the primary mechanism of SOA production from α-pinene + NO3 under simulated nighttime conditions. We estimate an average nRO2 + nRO2 → ROOR branching ratio of ~18 %. Synergistic dimerization between nRO2 and RO2 derived from ozonolysis and OH oxidation also contribute to SOA formation, and should be considered in models. We report a 58 (±20) % molar yield of PNP from the nRO2 + HO2 pathway. Applying these laboratory constraints to model simulations of summertime conditions observed in the Southeast United States (where 80 % of α-pinene is lost via NO3 oxidation, leading to 20 % nRO2 + nRO2 and 45 % nRO2 + HO2) , we estimate yields of 13% SOA and 9% particulate nitrate by mass, and 26 % PNP by mole, from α-pinene + NO3 in the ambient. These results suggest that α-pinene + NO3 significantly contributes to the SOA budget, and likely constitutes a major removal pathway of reactive nitrogen from the nighttime boundary layer in mixed biogenic/anthropogenic areas.

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Nocturnal isoprene oxidation over the Northeast United States in summer and its impact on reactive nitrogen partitioning and secondary organic aerosol

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-9-225-2009 ◽

2009 ◽

Vol 9 (1) ◽

pp. 225-269

Author(s):

S. S. Brown ◽

J. A. deGouw ◽

C. Warneke ◽

T. B. Ryerson ◽

W. P. Dubé ◽

...

Keyword(s):

Secondary Organic Aerosol ◽

Organic Aerosol ◽

Nitrogen Partitioning ◽

Photochemical Oxidation ◽

Reactive Nitrogen ◽

Organic Nitrates ◽

Isoprene Oxidation ◽

Northeast Us ◽

Aircraft Study

Abstract. Isoprene is the largest single VOC emission to the atmosphere. Although it is primarily oxidized photochemically during daylight hours, late-day emissions that remain in the atmosphere at sunset undergo oxidation by NO3 in regionally polluted areas with large NOx levels. A recent aircraft study examined isoprene and its nocturnal oxidants in a series of night flights across the Northeast US, a region with large emissions of both isoprene and NOx. Substantial amounts of isoprene that were observed after dark were strongly anticorrelated with measured NO3 and were the most important factor determining the lifetime of this radical. The products of photochemical oxidation of isoprene, methyl vinyl ketone and methacrolein, were more uniformly distributed, and served as tracers for the presence of isoprene at sunset, prior to its oxidation by NO3. Comparison of a determination of the mass of isoprene oxidized in darkness by NO3 to a calculation of integrated isoprene emissions showed that large amounts (>20%) of emitted isoprene may undergo nocturnal oxidation in this region. Organic nitrates produced from the NO3+isoprene reaction, though not directly measured, were estimated to account for 2–9% of total reactive nitrogen and 7–31% of other long-lived organic nitrates such as PAN. The mass of isoprene oxidized by NO3 was comparable to and correlated with the organic aerosol loading for flights with relatively low organic aerosol background. The contribution of nocturnal isoprene oxidation to secondary organic aerosol was determined in the range 1–17%, and isoprene SOA mass derived from NO3 was calculated to exceed that due to OH by approximately 50%.

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Nocturnal isoprene oxidation over the Northeast United States in summer and its impact on reactive nitrogen partitioning and secondary organic aerosol

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-3027-2009 ◽

2009 ◽

Vol 9 (9) ◽

pp. 3027-3042 ◽

Cited By ~ 102

Author(s):

S. S. Brown ◽

J. A. deGouw ◽

C. Warneke ◽

T. B. Ryerson ◽

W. P. Dubé ◽

...

Keyword(s):

Secondary Organic Aerosol ◽

Large Fraction ◽

Organic Aerosol ◽

Nitrogen Partitioning ◽

Photochemical Oxidation ◽

Reactive Nitrogen ◽

Organic Nitrates ◽

Isoprene Oxidation ◽

Northeast Us

Abstract. Isoprene is the largest single VOC emission to the atmosphere. Although it is primarily oxidized photochemically during daylight hours, late-day emissions that remain in the atmosphere at sunset undergo oxidation by NO3 in regionally polluted areas with large NOx levels. A recent aircraft study examined isoprene and its nocturnal oxidants in a series of night flights across the Northeast US, a region with large emissions of both isoprene and NOx. Substantial amounts of isoprene that were observed after dark were strongly anticorrelated with measured NO3 and were the most important factor determining the lifetime of this radical. The products of photochemical oxidation of isoprene, methyl vinyl ketone and methacrolein, were more uniformly distributed, and served as tracers for the presence of isoprene at sunset, prior to its oxidation by NO3. A determination of the mass of isoprene oxidized in darkness showed it to be a large fraction (>20%) of emitted isoprene. Organic nitrates produced from the NO3+isoprene reaction, though not directly measured, were estimated to account for 2–9% of total reactive nitrogen. The mass of isoprene oxidized by NO3 was comparable to and correlated with the organic aerosol loading for flights with relatively low organic aerosol background. The contribution of nocturnal isoprene oxidation to secondary organic aerosol was determined in the range 1–17%, and isoprene SOA mass derived from NO3 was calculated to exceed that due to OH by approximately 50%.

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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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