Articles | Volume 17, issue 8
https://doi.org/10.5194/acp-17-5107-2017
https://doi.org/10.5194/acp-17-5107-2017
Research article
 | 
19 Apr 2017
Research article |  | 19 Apr 2017

Inconsistency of ammonium–sulfate aerosol ratios with thermodynamic models in the eastern US: a possible role of organic aerosol

Rachel F. Silvern, Daniel J. Jacob, Patrick S. Kim, Eloise A. Marais, Jay R. Turner, Pedro Campuzano-Jost, and Jose L. Jimenez

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Cited articles

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We identify a fundamental discrepancy between thermodynamic equilibrium theory and observations of inorganic aerosol composition in the eastern US in summer that shows low ammonium sulfate aerosol ratios. In addition, from 2003 to 2013, while SO2 emissions have declined due to US emission controls, aerosols have become more acidic in the southeastern US. To explain these observations, we suggest that the large and increasing source of organic aerosol may be affecting thermodynamic equilibrium.
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