| Title: | Measurement and minutely-resolved source apportionment of ambient VOCs in a corridor city during 2019 China International Import Expo episode |
| Author(s): | Zhang Z; Man H; Qi L; Wang X; Liu H; Zhao J; Wang H; Jing S; He T; Wang S; He K; |
| Address: | "State Key Joint Laboratory of ESPC, State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, School of Environment, Tsinghua University, Beijing 100084, China. Digital Fujian Internet-of-things Laboratory of Environmental Monitoring, School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, China. College of Eco-environmental Engineering, Qinghai University, Xining 810016, China. State Key Joint Laboratory of ESPC, State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, School of Environment, Tsinghua University, Beijing 100084, China. Electronic address: liu_env@tsinghua.edu.cn. State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China. Changzhou Environmental Monitoring Center of Jiangsu Province, Changzhou 213001, China" |
| DOI: | 10.1016/j.scitotenv.2021.149375 |
| ISSN/ISBN: | 1879-1026 (Electronic) 0048-9697 (Linking) |
| Abstract: | "In this study, real-time measurement of Volatile Organic Compounds (VOCs) was conducted at an urban site in Changzhou, a typical corridor city in the Yangtze River Delta (YRD) region in China, by Proton-Transfer-Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS) during 2019 China International Import Expo (CIIE) episode. An improved method based on Air Quality Index (AQI) value is applied to identify polluted and clean periods. Diurnal pattern of VOC levels revealed elevated photochemical reactivity during polluted periods. Five VOC sources were identified by Positive Matrix Factorization (PMF) model, including secondary formation (22.71 +/- 12.33%), biogenic (21.50% +/- 11.76%), solvent usage (20.50 +/- 10.07%), vehicle exhaust (18.32 +/- 8.32%), and industrial process and fuel usage (16.96 +/- 13.21%). The mean contribution of vehicular exhaust was 10.84% higher during the nighttime than the daytime under polluted days. The biogenic source contributed more during clean periods, while the secondary formation presented the opposite. Spatial analysis displayed that the VOC concentration was higher in the S and SSE. In terms of the regional transport, short-distance air masses from the northeast and the south within the YRD region led to high VOC levels and biogenic VOC derived from the ocean might affect the entire region. Stringent emission control policies enforced over the YRD for 2019 CIIE provided an excellent opportunity to determine the source-receptor response. As joint control area, the VOC level of Changzhou exhibited a substantial reduction and the VOC amounts emitted by solvent usage showed the biggest decrease (-58%). The findings of this study highlight the superiority of high time-resolved data in identifying the dynamic variation pattern (with the change of time and wind) of VOC levels and emission intensities" |
| Keywords: | *Air Pollutants/analysis China Environmental Monitoring *Ozone/analysis *Volatile Organic Compounds/analysis 2019 China International Import Expo Emission control policies PTR-ToF-MS Regional transport Source apportionment VOCs; |
| Notes: | "MedlineZhang, Zhining Man, Hanyang Qi, Lijuan Wang, Xiaotong Liu, Huan Zhao, Junchao Wang, Hongli Jing, Shengao He, Tao Wang, Shuxiao He, Kebin eng Netherlands 2021/08/11 Sci Total Environ. 2021 Dec 1; 798:149375. doi: 10.1016/j.scitotenv.2021.149375. Epub 2021 Jul 31" |
