| Title: | Urban canopy height ozone distribution in a Chinese inland city: Effects of anthropogenic NO emissions |
| Author(s): | Guan Y; Shen Y; Wu T; Su W; Li D; Ni S; Zhang T; Han J; Duan E; |
| Address: | "School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China; National Joint Local Engineering Research Center for Volatile Organic Compounds and Odorous Pollution Control, Shijiazhuang 050018, China. School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China. HeBei Provincial Academy of Ecological Environmental Science, Shijiazhuang 050018, China. Shijiazhuang City Environmental Prediction and Forecast Center, Shijiazhuang 050018, China. Shijiazhuang Environmental Monitoring Center, Shijiazhuang 050021, China. School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China; National Joint Local Engineering Research Center for Volatile Organic Compounds and Odorous Pollution Control, Shijiazhuang 050018, China. Electronic address: duan_eh@163.com" |
| DOI: | 10.1016/j.scitotenv.2023.167448 |
| ISSN/ISBN: | 1879-1026 (Electronic) 0048-9697 (Linking) |
| Abstract: | "With the increase of urban building height, people pay more and more attention to the characteristics of pollutants in urban canopy height. This study combined the generalized additive model (GAM) and the observation-based model (OBM) to explore the vertical characteristics and drivers of ozone (O(3)) based on meteorology tower (200 m) data to quantify the effects of factors and photochemical reactions on O(3) formation at different heights. The F values of GAM reflect the importance of each factor, indicating that NO (F is 33.99 in the peak season, 36.72 in the non-peak season) was the dominant driver of O(3) and was more important in the lower layer (20-116 m). Temperature (F is 35.42) was the main contributor to O(3) pollution in the peak season, especially for O(3) in the upper layer (116-200 m). The net O(3) production rate in the peak season was 1.47 times that in the non-peak season due to strong photochemical reactions and meteorological conditions. And the net O(3) production rate decreased sharply with increasing height in the two seasons. Less net O(3) production in the upper layer was accompanied by a higher O(3) mixing ratio, which indicated that there was more background O(3) in the upper layer. OBM model results showed that the reaction between hydroperoxyl radical (HO(2)) and NO was the primary contribution pathway, accounting for 54.00 % and 57.50 % in the peak and non-peak seasons, respectively. O(3) formation was highly sensitive to VOCs, while NOx reduction could have positive or negative effects on O(3) depending on the levels of hydroxyl radical (OH). The understanding of the formation mechanism of O(3) and the influence of NO on O(3) provides insights into the importance of anthropogenic activities at urban canopy heights in shaping the vertical structure of O(3)" |
| Keywords: | Drivers GAM analysis Obm-mcm Photochemical reaction Vertical distribution; |
| Notes: | "PublisherGuan, Yanan Shen, Ying Wu, Tianyuan Su, Wenkang Li, Dong Ni, Shuangying Zhang, Tao Han, Jing Duan, Erhong eng Netherlands 2023/10/01 Sci Total Environ. 2023 Sep 28; 905:167448. doi: 10.1016/j.scitotenv.2023.167448" |
