Nighttime Chemical Transformation in Biomass Burning Plumes: A Box Model Analysis Initialized with Aircraft Observations
Autor: | William P. Dubé, Carsten Warneke, Joost A. de Gouw, James M. Roberts, Matthew M. Coggon, Kelley C. Barsanti, Kyung-Eun Min, Thomas B. Ryerson, Jeff Peischl, Ilana B. Pollack, Martin Graus, Lindsay E. Hatch, Milos Z. Markovic, Peter Edwards, Z. Decker, Kyle J. Zarzana, Steven S. Brown, Patrick R. Veres |
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Rok vydání: | 2019 |
Předmět: |
Aerosols
Daytime Chemical transformation Box model Aircraft Atmosphere Biomass General Chemistry 010501 environmental sciences Atmospheric sciences 01 natural sciences Fires Aerosol Box modeling Environmental Chemistry Environmental science Biomass burning 0105 earth and related environmental sciences |
Zdroj: | Environmental Science & Technology. 53:2529-2538 |
ISSN: | 1520-5851 0013-936X |
Popis: | Biomass burning (BB) is a large source of reactive compounds in the atmosphere. While the daytime photochemistry of BB emissions has been studied in some detail, there has been little focus on nighttime reactions despite the potential for substantial oxidative and heterogeneous chemistry. Here, we present the first analysis of nighttime aircraft intercepts of agricultural BB plumes using observations from the NOAA WP-3D aircraft during the 2013 Southeast Nexus (SENEX) campaign. We use these observations in conjunction with detailed chemical box modeling to investigate the formation and fate of oxidants (NO3, N2O5, O3, and OH) and BB volatile organic compounds (BBVOCs), using emissions representative of agricultural burns (rice straw) and western wildfires (ponderosa pine). Field observations suggest NO3 production was approximately 1 ppbv hr-1, while NO3 and N2O5 were at or below 3 pptv, indicating rapid NO3/N2O5 reactivity. Model analysis shows that >99% of NO3/N2O5 loss is due to BBVOC + NO3 reactions rather than aerosol uptake of N2O5. Nighttime BBVOC oxidation for rice straw and ponderosa pine fires is dominated by NO3 (72, 53%, respectively) but O3 oxidation is significant (25, 43%), leading to roughly 55% overnight depletion of the most reactive BBVOCs and NO2. |
Databáze: | OpenAIRE |
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