Differences in BVOC oxidation and SOA formation above and below the forest canopy
| dc.citation.articleNumber | 1805 | |
| dc.citation.firstpage | 1828 | en_US |
| dc.citation.journalTitle | Atmospheric Chemistry and Physics | en_US |
| dc.citation.volumeNumber | 17 | en_US |
| dc.contributor.author | Schulze, Benjamin C. | en_US |
| dc.contributor.author | Wallace, Henry W. | en_US |
| dc.contributor.author | Flynn, James H. | en_US |
| dc.contributor.author | Lefer, Barry L. | en_US |
| dc.contributor.author | Erickson, Matt H. | en_US |
| dc.contributor.author | Jobson, B. Tom | en_US |
| dc.contributor.author | Dusanter, Sebastien | en_US |
| dc.contributor.author | Griffith, Stephen M. | en_US |
| dc.contributor.author | Hansen, Robert F. | en_US |
| dc.contributor.author | Stevens, Philip S. | en_US |
| dc.contributor.author | VanReken, Timothy | en_US |
| dc.contributor.author | Griffin, Robert J. | en_US |
| dc.date.accessioned | 2017-03-07T17:07:15Z | |
| dc.date.available | 2017-03-07T17:07:15Z | |
| dc.date.issued | 2017 | en_US |
| dc.description.abstract | Gas-phase biogenic volatile organic compounds (BVOCs) are oxidized in the troposphere to produce secondary pollutants such as ozone (O3), organic nitrates (RONO2), and secondary organic aerosol (SOA). Two coupled zero-dimensional models have been used to investigate differences in oxidation and SOA production from isoprene and α-pinene, especially with respect to the nitrate radical (NO3), above and below a forest canopy in rural Michigan. In both modeled environments (above and below the canopy), NO3 mixing ratios are relatively small (< 0.5 pptv); however, daytime (08:00–20:00 LT) mixing ratios below the canopy are 2 to 3 times larger than those above. As a result of this difference, NO3 contributes 12 % of total daytime α-pinene oxidation below the canopy while only contributing 4 % above. Increasing background pollutant levels to simulate a more polluted suburban or peri-urban forest environment increases the average contribution of NO3 to daytime below-canopy α-pinene oxidation to 32 %. Gas-phase RONO2 produced through NO3 oxidation undergoes net transport upward from the below-canopy environment during the day, and this transport contributes up to 30 % of total NO3-derived RONO2 production above the canopy in the morning (∼ 07:00). Modeled SOA mass loadings above and below the canopy ultimately differ by less than 0.5 µg m−3, and extremely low-volatility organic compounds dominate SOA composition. Lower temperatures below the canopy cause increased partitioning of semi-volatile gas-phase products to the particle phase and up to 35 % larger SOA mass loadings of these products relative to above the canopy in the model. Including transport between above- and below-canopy environments increases above-canopy NO3-derived α-pinene RONO2 SOA mass by as much as 45 %, suggesting that below-canopy chemical processes substantially influence above-canopy SOA mass loadings, especially with regard to monoterpene-derived RONO2. | en_US |
| dc.identifier.citation | Schulze, Benjamin C., Wallace, Henry W., Flynn, James H., et al.. "Differences in BVOC oxidation and SOA formation above and below the forest canopy." <i>Atmospheric Chemistry and Physics,</i> 17, (2017) Copernicus Publications on behalf of the European Geosciences Union: 1828. http://dx.doi.org/10.5194/acp-17-1805-2017. | |
| dc.identifier.doi | http://dx.doi.org/10.5194/acp-17-1805-2017 | en_US |
| dc.identifier.uri | https://hdl.handle.net/1911/94020 | |
| dc.language.iso | eng | en_US |
| dc.publisher | Copernicus Publications on behalf of the European Geosciences Union | |
| dc.rights | This work is distributed under the Creative Commons Attribution 3.0 License. | en_US |
| dc.rights.uri | https://creativecommons.org/licenses/by/3.0/us/ | en_US |
| dc.title | Differences in BVOC oxidation and SOA formation above and below the forest canopy | en_US |
| dc.type | Journal article | en_US |
| dc.type.dcmi | Text | en_US |
| dc.type.publication | publisher version | en_US |