Atmospheric oxidation chemistry and ozone production: Results from SHARP 2009 in Houston, Texas

作者：Xinrong Ren, Diana van Duin, M. Cazorla, Shuang Chen, Jingqiu Mao, Li Zhang, W. H. Brune, James Flynn, N. Grossberg, B. L. Lefer, Bernhard Rappenglück, Kam W. Wong, Catalina Tsai, J. Stutz, Jack E. Dibb, B. T. Jobson, Winston T. Luke, Paul Kelley · 发表于：Journal of Geophysical Research Atmospheres · 年份：2013 · DOI：10.1002/jgrd.50342 · 被引用次数：181 · 研究领域：Atmospheric chemistry and aerosols、Air Quality and Health Impacts、Air Quality Monitoring and Forecasting

Ozone (O 3 ) and secondary fine particles come from the atmospheric oxidation chemistry that involves the hydroxyl radical (OH) and hydroperoxyl radical (HO 2 ), which are together called HO x . Radical precursors such as nitrous acid (HONO) and formaldehyde (HCHO) significantly affect the HO x budget in urban environments. These chemical processes connect surface anthropogenic and natural emissions to local and regional air pollution. Using the data collected during the Study of Houston Atmospheric Radical Precursors (SHARP) in spring 2009, we examine atmospheric oxidation chemistry and O 3 production in this polluted urban environment. A numerical box model with five different chemical mechanisms was used to simulate the oxidation processes and thus OH and HO 2 in this study. In general, the model reproduced the measured OH and HO 2 with all five chemical mechanisms producing similar levels of OH and HO 2 , although midday OH was overpredicted and nighttime OH and HO 2 were underpredicted. The calculated HO x production was dominated by HONO photolysis in the early morning and by the photolysis of O 3 and oxygenated volatile organic compounds (OVOCs) in the midday. On average, the daily HO x production rate was 24.6 ppbv d −1 , of which 30% was from O 3 photolysis, 22% from HONO photolysis, 15% from the photolysis of OVOCs (other than HCHO), 14% from HCHO photolysis, and 13% from O 3 reactions with alkenes. The O 3 production was sensitive to volatile organic compounds (VOC...