| Title: | "Inferring vertical variability and diurnal evolution of O(3) formation sensitivity based on the vertical distribution of summertime HCHO and NO(2) in Guangzhou, China" |
| Author(s): | Hong Q; Zhu L; Xing C; Hu Q; Lin H; Zhang C; Zhao C; Liu T; Su W; Liu C; |
| Address: | "School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China. Key Lab of Environmental Optics & Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Guangzhou 510632, China. Electronic address: xingcz@aiofm.ac.cn. Key Lab of Environmental Optics & Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China. School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, China. Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei 230026, China. School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China. Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Key Lab of Environmental Optics & Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei 230026, China; Anhui Province Key Laboratory of Polar Environment and Global Change, University of Science and Technology of China, Hefei 230026, China. Electronic address: chliu81@ustc.edu.cn" |
| DOI: | 10.1016/j.scitotenv.2022.154045 |
| ISSN/ISBN: | 1879-1026 (Electronic) 0048-9697 (Linking) |
| Abstract: | "The vertical distributions of formaldehyde (HCHO) and nitrogen dioxide (NO(2)) and their indicative roles in ozone (O(3)) sensitivity are important for designing O(3) mitigation strategies. Using hyperspectral remote sensing observations, tropospheric vertical profiles of HCHO, NO(2), and aerosol extinction were investigated in Guangzhou, China from July to September 2019. On both O(3) non-exceedance and polluted days, the HCHO and aerosol vertical profiles exhibited similar Gaussian shapes, but the NO(2) profile exhibited an exponential decreasing shape. HCHO and aerosol were especially sensitive to O(3) pollution, with higher values generally occurring at approximately noon and late afternoon at higher altitudes. We attempted to study the diurnal evolution of O(3) sensitivity at different altitudes based on the HCHO to NO(2) ratio (FNR) vertical profile. The FNR thresholds marking the transition regime (2.5 < FNR < 4.0) were derived from the relationship between the increase in O(3) (?OsO(3)) and FNR. Our results showed that O(3) sensitivity tends to be VOC-limited both at lower (below approximately 0.4 km) and higher (above approximately 1.8 km) altitudes throughout the daytime. In the middle altitudes, the photochemical formation of O(3) was mainly in the transition/NO(x)-limited regime in the morning and afternoon but in the VOC-limited regime at noontime. The relationship between TROPOMI column FNR and near-surface O(3) sensitivity was further investigated. Compared with the MAX-DOAS near-surface FNR, slightly higher values of column FNR would increase the number of days classified as transition regimes, which was mainly caused by the inhomogeneous vertical distribution of HCHO and NO(2) in the lower troposphere. This study provides an improved understanding of vertical variability and diurnal evolution of O(3) formation sensitivity" |
| Keywords: | *Air Pollutants/analysis China Environmental Monitoring/methods Nitrogen Dioxide/analysis *Ozone/analysis Photochemical Processes *Volatile Organic Compounds/analysis Formaldehyde Max-doas Nitrogen oxides Ozone formation sensitivity Tropomi; |
| Notes: | "MedlineHong, Qianqian Zhu, Linbin Xing, Chengzhi Hu, Qihou Lin, Hua Zhang, Chengxin Zhao, Chunhui Liu, Ting Su, Wenjing Liu, Cheng eng Netherlands 2022/02/27 Sci Total Environ. 2022 Jun 25; 827:154045. doi: 10.1016/j.scitotenv.2022.154045. Epub 2022 Feb 22" |
