Influence of mineral dust and sea spray supermicron particle concentrations and acidity on inorganic NO<sub>3</sub><sup>−</sup> aerosol during the 2013 Southern Oxidant and Aerosol Study
Author:
Allen H. M., Draper D. C., Ayres B. R., Ault A.ORCID, Bondy A., Takahama S.ORCID, Modini R. L.ORCID, Baumann K.ORCID, Edgerton E., Knote C., Laskin A.ORCID, Wang B., Fry J. L.ORCID
Abstract
Abstract. The inorganic aerosol composition was measured in the southeastern United States, a region that exhibits high aerosol mass loading during the summer, as part of the 1 June to 15 July 2013 Southern Oxidant and Aerosol Study (SOAS) campaign. Measurements using a Monitor for AeRosols and GAses (MARGA), an ion chromatograph coupled with a wet rotating denuder and a steam-jet aerosol collector for monitoring of ambient inorganic gas and aerosol species, revealed two periods of high aerosol nitrate (NO3−) concentrations during the campaign. These periods of high nitrate were correlated with increased concentrations of coarse mode mineral or sea spray aerosol species, particularly Na+ and Ca2+, and with a shift towards aerosol with larger (1 to 2.5 μm) diameters. We suggest this nitrate aerosol forms by multiphase reactions of HNO3 and particles, reactions that are facilitated by transport of mineral dust and sea spray aerosol from a source within the United States. The observed high aerosol acidity prevents the formation of NH4NO3, the inorganic nitrogen species often dominant in fine-mode aerosol at higher pH. Calculation of the rate of the heterogeneous uptake of HNO3 on mineral aerosol supports the conclusion that aerosol NO3− is produced primarily by this process, and is likely limited by the availability of mineral dust surface area. Modeling of NO3− and HNO3 by thermodynamic equilibrium models (ISORROPIA II and E-AIM) reveals the importance of including mineral cations in the southeastern United States to accurately balance ion species and predict gas/aerosol phase partitioning.
Funder
U.S. Environmental Protection Agency
Publisher
Copernicus GmbH
Reference72 articles.
1. Ault, A. P., Peters, T. M., Sawvel, E. J., Casuccio, G. S., Willis, R. D., Norris, G. A., and Grassian, V. H.: Single-particle SEM-EDX analysis of iron-containing coarse particulate matter in an urban environment: sources and distribution of iron within Cleveland, Ohio, Environ. Sci. Technol., 46, 4331–4339, 2012. 2. Ault, A. P., Guasco, T. L., Ryder, O. S., Baltrusaitis, J. Cuadra-Rodriguez, L. A., Collins, D. B., Ruppel, M. J., Bertram, T. H., Prather, K. A., and Grassian, V. H.: Inside versus outside: ion redistribution in nitric acid reacted sea spray aerosol particles as determined by single-particle analysis, J. Am. Chem. Soc., 135, 14528–14531, 2013a. 3. Ault, A. P., Moffet, R. C., Baltrusaitis, J., Collins, D. B., Ruppel, M. J., Cuadra-Rodriguez, L. A., Zhao, D., Guasco, T. L., Ebben, C. J., Geiger, F. M., Bertram, T. H., Prather, K. A., and Grassian, V. H.: Size-dependent changes in sea spray aerosol composition and properties with different seawater conditions, Environ. Sci. Technol., 47, 5603–5612, 2013b. 4. Ayres, B. R., Allen, H. M., Draper, D. C., Brown, S. S., Jimenez, J. L., Day, D. A., De Gouw, J., Cohen, R. C., Baumann, K., Takahama, S., Thornton, J. A., Goldstein, A. H., and Fry, J. L.: NOy fate at SOAS 2013: organonitrate formation via NO3+BVOC and inorganic nitrate formation via heterogeneous uptake of HNO3, in preparation, 2015. 5. Baker, K. and Scheff, P.: Photochemical model performance for PM2.5 sulfate, nitrate, ammonium, and precursor species SO2, HNO3, and NH3 at background monitor locations in the central and eastern United States, Atmos. Environ., 41, 6185–6195, 2007.
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