Secondary organic aerosol and organic nitrogen yields from the nitrate radical (NO₃) oxidation of alpha-pinene from various RO₂ fates

Abstract α 3 is an important sink of both α 3 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 + 3 as a function of nitrooxy peroxy (n 2) radical fates with HO2, NO, NO3, and RO2 in an atmospheric chamber. We show that SOA yields are not small when the n 2 fate distribution in the chamber mimics that in the atmosphere, and the formation of pinene nitrooxy hydroperoxide (PNP) and related organonitrates in the ambient atmosphere can be reproduced. Nearly all SOA from α + 3 chemistry derives from the n 2 +  RO2 pathway, which alone has an SOA mass yield of 56 (± α + 3 under simulated nighttime conditions. Synergistic dimerization between n 2 and RO2 derived from ozonolysis and OH oxidation also contribute to SOA formation and should be considered in models. We report a 58 (± n 2 +  HO2 pathway. Applying these laboratory constraints to model simulations of summertime conditions observed in the southeast United States (where 80 % of α 3 oxidation, leading to 20 % n 2 +  RO2 and 45 % n 2 +  HO2), we estimate yields of 11 % SOA and 7 % particulate nitrate by mass and 26 % PNP by mole from α + 3 in the ambient atmosphere. These results suggest that α + 3 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.

Angaben zum Objekt

• Standort: Deutsche Nationalbibliothek Frankfurt am Main
• Umfang: Online-Ressource
• Sprache: Englisch

Verweise und Beziehungen

• Erschienen in: Secondary organic aerosol and organic nitrogen yields from the nitrate radical (NO₃) oxidation of alpha-pinene from various RO₂ fates ; volume:22 ; number:2 ; year:2022 ; pages:1467-1482 ; extent:16 ; Atmospheric chemistry and physics ; 22, Heft 2 (2022), 1467-1482 (gesamt 16)

Beteiligte, Orts- und Zeitangaben

• Urheber: Bates, Kelvin H. ; Burke, Guy J. P. ; Cope, James D. ; Nguyen, Tran B.

Weitere Informationen

• DOI: 10.5194/acp-22-1467-2022
• URN: urn:nbn:de:101:1-2022020304195847650274
• Rechteinformation: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Letzte Aktualisierung: 15.08.2202, 07:32 MESZ