Title: | "Reconciling the bottom-up methodology and ground measurement constraints to improve the city-scale NMVOCs emission inventory: A case study of Nanjing, China" |
Author(s): | Wu R; Zhao Y; Xia S; Hu W; Xie F; Zhang Y; Sun J; Yu H; An J; Wang Y; |
Address: | "State Key Laboratory of Pollution Control & Resource Reuse and School of the Environment, Nanjing University, 163 Xianlin Ave., Nanjing, Jiangsu 210023, China. State Key Laboratory of Pollution Control & Resource Reuse and School of the Environment, Nanjing University, 163 Xianlin Ave., Nanjing, Jiangsu 210023, China; Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, CICAEET, Nanjing, Jiangsu 210044, China. Electronic address: yuzhao@nju.edu.cn. Jiangsu Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Sciences, Nanjing, Jiangsu 210036, China. Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China. Nanjing Municipal Academy of Ecology and Environment Protection Science, Nanjing, Jiangsu 210093, China. Jiangsu Environmental Engineering and Technology Co., Ltd, Jiangsu Environmental Protection Group Co., Nanjing, Jiangsu 210019, China. School of Environmental Studies, China University of Geosciences, Wuhan, Hubei 430074, China. Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, Jiangsu 210044, China" |
DOI: | 10.1016/j.scitotenv.2021.152447 |
ISSN/ISBN: | 1879-1026 (Electronic) 0048-9697 (Linking) |
Abstract: | "Reliable emission estimate of non-methane volatile organic compounds (NMVOCs) is important for understanding the atmospheric chemistry and formulating control policy of ozone (O(3)). In this study, a speciated emission inventory of anthropogenic NMVOCs was developed with the refined 'bottom-up' methodology and best available information of individual sources for Nanjing in 2017. The total NMVOCs emissions were calculated at 163.2 Gg. It was broken down into the emissions of over 500 individual species and aromatics took the largest fraction (33.3% of the total emissions). Meanwhile, 105 compounds were measured at 5 sites representing different functional zones of Nanjing for one year. The annual mean concentration of totally 105 species varied from 48.5 ppbv to 63.7 ppbv, and alkanes was the most abundant group with its mass fractions ranging 37.2-40.1% at different sites. Constrained by the emission ratios of individual species versus carbon monoxide (CO) based on ground measurement, the total emissions of 105 species (NMVOCs-105) was estimated at 195.6 Gg, 81.1% larger than the bottom-up estimate of NMVOCs-105 (108.0 Gg). The constrained emissions indicated an overestimation of aromatics and underestimation of OVOCs and halocarbons in the bottom-up emission inventory because of the uncertainties in source profiles. O(3) simulation with Community Multi-scale Air Quality (CMAQ) model was conducted for January, April, July and October in 2017 to evaluate the bottom-up and constrained emission estimates. The mean normal bias (MNB) and mean normal error (MNE) values were generally within the criteria (MNB = +/-15% and MNE = 30%) for both inventories. The model performance was improved when the constrained estimates were applied, indicating the benefit of ground observation constraints on NMVOCs emission estimation and O(3) simulation. Based on the O(3) formation potential (OFP), 12 key NMVOCs species mainly from surface coating, on-road vehicles and oil exploitation and refinery were identified as the priority compounds for O(3) reduction" |
Keywords: | *Air Pollutants/analysis China Environmental Monitoring Methane *Ozone/analysis *Volatile Organic Compounds/analysis Cmaq Constraint Emission inventory NMVOCs Ozone formation potential; |
Notes: | "MedlineWu, Rongrong Zhao, Yu Xia, Sijia Hu, Wei Xie, Fangjian Zhang, Yan Sun, Jinjin Yu, Huan An, Junlin Wang, Yutong eng Netherlands 2021/12/24 Sci Total Environ. 2022 Mar 15; 812:152447. doi: 10.1016/j.scitotenv.2021.152447. Epub 2021 Dec 21" |