Back to Search
Start Over
Tropospheric sources and sinks of gas-phase acids in the Colorado Front Range.
- Source :
- Atmospheric Chemistry & Physics Discussions; 2018, p1-22, 22p
- Publication Year :
- 2018
-
Abstract
- We measured organic and inorganic gas-phase acids in the Front Range of Colorado to better understand their tropospheric sources and sinks using a high-resolution time-of-flight chemical ionization mass spectrometer. Measurements were conducted from 4 to 13 August 2014 at the Boulder Atmospheric Observatory during the Front Range Air Pollution and Photochemistry Éxperiment. Diurnal increases in mixing ratios are consistent with photochemical sources of HNO<subscript>3</subscript>, HNCO, formic, propionic, butyric, valeric, and pyruvic acid. Vertical profiles taken on the 300 m tower demonstrate net surface-level emissions of alkanoic acids, but net surface deposition of HNO<subscript>3</subscript> and pyruvic acid. The surface-level alkanoic acid source persists through both day and night, and is thus not solely photochemical. Reactions between O<subscript>3</subscript> and organic surfaces may contribute to the surface-level alkanoic acid source. Nearby traffic emissions and agricultural activity are a primary source of propionic, butyric, and valeric acid, and likely contribute photochemical precursors to HNO<subscript>3</subscript> and HNCO. The combined diel and vertical profiles of the alkanoic acids and HNCO are inconsistent with dry deposition and photochemical losses being the only sinks, suggesting additional loss mechanisms. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 16807367
- Database :
- Complementary Index
- Journal :
- Atmospheric Chemistry & Physics Discussions
- Publication Type :
- Academic Journal
- Accession number :
- 129462898
- Full Text :
- https://doi.org/10.5194/acp-2018-326