Articles | Volume 20, issue 16
https://doi.org/10.5194/acp-20-9871-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-20-9871-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
25 Aug 2020
Research article |
| 25 Aug 2020
| 25 Aug 2020
Tracking separate contributions of diesel and gasoline vehicles to roadside PM2.5 through online monitoring of volatile organic compounds and PM2.5 organic and elemental carbon: a 6-year study in Hong Kong
Yee Ka Wong
Division of Environment & Sustainability, Hong Kong University of
Science & Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
X. H. Hilda Huang
Division of Environment & Sustainability, Hong Kong University of
Science & Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
Peter K. K. Louie
Hong Kong Environmental Protection Department, 47/F, Revenue Tower, 5 Gloucester Road, Wan Chai, Hong Kong SAR, China
Alfred L. C. Yu
Hong Kong Environmental Protection Department, 47/F, Revenue Tower, 5 Gloucester Road, Wan Chai, Hong Kong SAR, China
Damgy H. L. Chan
Hong Kong Environmental Protection Department, 47/F, Revenue Tower, 5 Gloucester Road, Wan Chai, Hong Kong SAR, China
Division of Environment & Sustainability, Hong Kong University of
Science & Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
Department of Chemistry, Hong Kong University of Science &
Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
Related authors
Taylor D. Edwards, Yee Ka Wong, Cheol-Heon Jeong, Jonathan M. Wang, Yushan Su, and Greg J. Evans
Atmos. Meas. Tech., 18, 2201–2240, https://doi.org/10.5194/amt-18-2201-2025, https://doi.org/10.5194/amt-18-2201-2025, 2025
Short summary
Short summary
We tested a variety of scientific measurements and algorithms for distinguishing the amounts of air pollution that were emitted by a nearby polluter from background pollution that was already in the air. The results show that machine learning and other statistical algorithms produced accurate estimates of this background pollution. These findings help scientists and regulators to understand where pollution comes from and to improve measurements of pollution from sources like traffic.
Rongshuang Xu, Sze In Madeleine Ng, Wing Sze Chow, Yee Ka Wong, Yuchen Wang, Donger Lai, Zhongping Yao, Pui-Kin So, Jian Zhen Yu, and Man Nin Chan
Atmos. Chem. Phys., 22, 5685–5700, https://doi.org/10.5194/acp-22-5685-2022, https://doi.org/10.5194/acp-22-5685-2022, 2022
Short summary
Short summary
To date, while over a hundred organosulfates (OSs) have been detected in atmospheric aerosols, many of them are still unidentified, with unknown precursors and formation processes. We found the heterogeneous OH oxidation of an α-pinene-derived organosulfate (C10H17O5SNa, αpOS-249, αpOS-249) can proceed at an efficient rate and transform into more oxygenated OSs, which have been commonly detected in atmospheric aerosols and α-pinene-derived SOA in chamber studies.
Yee Ka Wong, Kin Man Liu, Claisen Yeung, Kenneth K. M. Leung, and Jian Zhen Yu
Atmos. Chem. Phys., 22, 5017–5031, https://doi.org/10.5194/acp-22-5017-2022, https://doi.org/10.5194/acp-22-5017-2022, 2022
Short summary
Short summary
Coarse particulate matter (PM) has been shown to cause adverse health impacts, but compared to PM2.5, the source of coarse PM is less studied through field measurements. We collected chemical composition data for coarse PM in Hong Kong for a 1-year period. Using statistical models, we found that regional transport of fugitive dust is responsible for the elevated coarse PM. This work sets an example of how field measurements can be effectively utilized for evidence-based policymaking.
Xu Yu, Min Zhou, Shuhui Zhu, Liping Qiao, Jinjian Li, Yingge Ma, Zijing Zhang, Kezheng Liao, Hongli Wang, and Jian Zhen Yu
Atmos. Chem. Phys., 25, 9061–9074, https://doi.org/10.5194/acp-25-9061-2025, https://doi.org/10.5194/acp-25-9061-2025, 2025
Short summary
Short summary
Online measurements of bulk aerosol organic nitrogen (ON), in conjunction with a comprehensive array of source markers, have revealed five emission sources and five potentially significant formation processes of nitrogenous organic aerosols. This study provides a first quantitative source analysis of ON aerosol and valuable observational evidence of secondary ON aerosol formation through NH3 and NOx chemistries.
Xueying Liu, Yeqi Huang, Yao Chen, Xin Feng, Yang Xu, Yi Chen, Dasa Gu, Hao Sun, Zhi Ning, Jianzhen Yu, Wing Sze Chow, Changqing Lin, Yan Xiang, Tianshu Zhang, Claire Granier, Guy Brasseur, Zhe Wang, and Jimmy C. H. Fung
EGUsphere, https://doi.org/10.5194/egusphere-2025-3227, https://doi.org/10.5194/egusphere-2025-3227, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Volatile organic compounds (VOCs) affect ozone formation and air quality. However, our understanding is limited due to insufficient measurements, especially for oxygenated VOCs. This study combines land, ship, and satellite data in Hong Kong, showing that oxygenated VOCs make up a significant portion of total VOCs. Despite their importance, many are underestimated in current models. These findings highlight the need to improve VOC representation in models to enhance air quality management.
Donger Lai, Yanxin Bai, Zijing Zhang, Pui-Kin So, Yong Jie Li, Ying-Lung Steve Tse, Ying-Yeung Yeung, Thomas Schaefer, Hartmut Herrmann, Jian Zhen Yu, Yuchen Wang, and Man Nin Chan
EGUsphere, https://doi.org/10.5194/egusphere-2025-2743, https://doi.org/10.5194/egusphere-2025-2743, 2025
Short summary
Short summary
Aqueous-phase •OH oxidation can potentially act as an important atmospheric sink for α-pinene-derived organosulfates (OSs). Such oxidation can also generate a variety of new OS products, and can be as a potential source for some atmospheric OSs with previously unknown origins.
Shubin Li, Yujue Wang, Yiwen Zhang, Yizhe Yi, Yuchen Wang, Yuqi Guo, Chao Yu, Yue Jiang, Jinhui Shi, Chao Zhang, Jialei Zhu, Wei Hu, Jianzhen Yu, Xiaohong Yao, Huiwang Gao, and Min Hu
EGUsphere, https://doi.org/10.5194/egusphere-2025-2154, https://doi.org/10.5194/egusphere-2025-2154, 2025
Short summary
Short summary
Organosulfates (OSs) are an unrecognized and potentially important component in marine organic aerosols. In this study, we quantified and characterized the OSs over East Asian marginal seas. The chemical nature and spatiotemporal distribution of OSs were modified by the joint influence of marine emissions and transported terrestrial pollutants. The results highlight the vital roles of OSs in shaping organic aerosol formation and sulfur cycle during summer in marine boundary layer.
Taylor D. Edwards, Yee Ka Wong, Cheol-Heon Jeong, Jonathan M. Wang, Yushan Su, and Greg J. Evans
Atmos. Meas. Tech., 18, 2201–2240, https://doi.org/10.5194/amt-18-2201-2025, https://doi.org/10.5194/amt-18-2201-2025, 2025
Short summary
Short summary
We tested a variety of scientific measurements and algorithms for distinguishing the amounts of air pollution that were emitted by a nearby polluter from background pollution that was already in the air. The results show that machine learning and other statistical algorithms produced accurate estimates of this background pollution. These findings help scientists and regulators to understand where pollution comes from and to improve measurements of pollution from sources like traffic.
Liyuan Zhou, Qianyun Liu, Christian M. Salvador, Michael Le Breton, Mattias Hallquist, Jian Zhen Yu, Chak K. Chan, and Åsa M. Hallquist
Atmos. Chem. Phys., 24, 11045–11061, https://doi.org/10.5194/acp-24-11045-2024, https://doi.org/10.5194/acp-24-11045-2024, 2024
Short summary
Short summary
Our research on city bus emissions reveals that alternative fuels (compressed natural gas and biofuels) reduce fresh particle emissions compared to diesel. However, all fuels lead to secondary air pollution. Aiming at guiding better environmental policies, we studied 76 buses using advanced emission measurement techniques. This work sheds light on the complex effects of bus fuels on urban air quality, emphasizing the need for comprehensive evaluations of future transportation technologies.
Shan Wang, Kezheng Liao, Zijing Zhang, Yuk Ying Cheng, Qiongqiong Wang, Hanzhe Chen, and Jian Zhen Yu
Atmos. Chem. Phys., 24, 5803–5821, https://doi.org/10.5194/acp-24-5803-2024, https://doi.org/10.5194/acp-24-5803-2024, 2024
Short summary
Short summary
In this work, hourly primary and secondary organic carbon were estimated by a novel Bayesian inference approach in suburban Hong Kong. Their multi-temporal-scale variations and evolution characteristics during PM2.5 episodes were examined. The methodology could serve as a guide for other locations with similar monitoring capabilities. The observation-based results are helpful for understanding the evolving nature of secondary organic aerosols and refining the accuracy of model simulations.
Qiongqiong Wang, Shuhui Zhu, Shan Wang, Cheng Huang, Yusen Duan, and Jian Zhen Yu
Atmos. Chem. Phys., 24, 475–486, https://doi.org/10.5194/acp-24-475-2024, https://doi.org/10.5194/acp-24-475-2024, 2024
Short summary
Short summary
We investigated short-term source apportionment of PM2.5 utilizing rolling positive matrix factorization (PMF) and online PM chemical speciation data, which included source-specific organic tracers collected over a period of 37 d during the winter of 2019–2020 in suburban Shanghai, China. The findings highlight that by imposing constraints on the primary source profiles, short-term PMF analysis successfully replicated both the individual primary sources and the total secondary sources.
Ting Yang, Yu Xu, Qing Ye, Yi-Jia Ma, Yu-Chen Wang, Jian-Zhen Yu, Yu-Sen Duan, Chen-Xi Li, Hong-Wei Xiao, Zi-Yue Li, Yue Zhao, and Hua-Yun Xiao
Atmos. Chem. Phys., 23, 13433–13450, https://doi.org/10.5194/acp-23-13433-2023, https://doi.org/10.5194/acp-23-13433-2023, 2023
Short summary
Short summary
In this study, 130 OS species were quantified in ambient fine particulate matter (PM2.5) collected in urban and suburban Shanghai (East China) in the summer of 2021. The daytime OS formation was concretized based on the interactions among OSs, ultraviolet (UV), ozone (O3), and sulfate. Our finding provides field evidence for the influence of photochemical process and anthropogenic sulfate on OS formation and has important implications for the mitigation of organic particulate pollution.
Shuhui Zhu, Min Zhou, Liping Qiao, Dan Dan Huang, Qiongqiong Wang, Shan Wang, Yaqin Gao, Shengao Jing, Qian Wang, Hongli Wang, Changhong Chen, Cheng Huang, and Jian Zhen Yu
Atmos. Chem. Phys., 23, 7551–7568, https://doi.org/10.5194/acp-23-7551-2023, https://doi.org/10.5194/acp-23-7551-2023, 2023
Short summary
Short summary
Organic aerosol (OA) is increasingly important in urban PM2.5 pollution as inorganic ions are becoming lower. We investigated the chemical characteristics of OA during nine episodes in Shanghai. The availability of bi-hourly measured molecular markers revealed that the control of local urban sources such as vehicular and cooking emissions lessened the severity of local episodes. Regional control of precursors and biomass burning would reduce PM2.5 episodes influenced by regional transport.
Rui Li, Kun Zhang, Qing Li, Liumei Yang, Shunyao Wang, Zhiqiang Liu, Xiaojuan Zhang, Hui Chen, Yanan Yi, Jialiang Feng, Qiongqiong Wang, Ling Huang, Wu Wang, Yangjun Wang, Jian Zhen Yu, and Li Li
Atmos. Chem. Phys., 23, 3065–3081, https://doi.org/10.5194/acp-23-3065-2023, https://doi.org/10.5194/acp-23-3065-2023, 2023
Short summary
Short summary
Molecular markers in organic aerosol (OA) provide specific source information on PM2.5, and the contribution of cooking emissions to OA is significant, especially in urban environments. This study investigates the variation in concentrations and oxidative degradation of fatty acids and corresponding oxidation products in ambient air, which can be a guide for the refinement of aerosol source apportionment and provide scientific support for the development of emission source control policies.
Wing Sze Chow, Kezheng Liao, X. H. Hilda Huang, Ka Fung Leung, Alexis K. H. Lau, and Jian Zhen Yu
Atmos. Chem. Phys., 22, 11557–11577, https://doi.org/10.5194/acp-22-11557-2022, https://doi.org/10.5194/acp-22-11557-2022, 2022
Short summary
Short summary
Long-term monitoring data of PM2.5 chemical composition provide essential information for evaluation and planning of control measures. Here we present a 10-year (2008–2017) time series of PM2.5, its major components, and select source markers in an urban site in Hong Kong. The dataset verified the success of local vehicular emission control measures as well as reduction of sulfate and regional sources such as industrial and coal combustion and crop residue burning emissions over the decade.
Qiongqiong Wang, Shan Wang, Yuk Ying Cheng, Hanzhe Chen, Zijing Zhang, Jinjian Li, Dasa Gu, Zhe Wang, and Jian Zhen Yu
Atmos. Chem. Phys., 22, 11239–11253, https://doi.org/10.5194/acp-22-11239-2022, https://doi.org/10.5194/acp-22-11239-2022, 2022
Short summary
Short summary
Secondary organic aerosol (SOA) is often enhanced during fine-particulate-matter (PM2.5) episodes. We examined bi-hourly measurements of SOA molecular tracers in suburban Hong Kong during 11 city-wide PM2.5 episodes. The tracers showed regional characteristics for both anthropogenic and biogenic SOA as well as biomass-burning-derived SOA. Multiple tracers of the same precursor revealed the dominance of low-NOx formation pathways for isoprene SOA and less-aged monoterpene SOA during winter.
Rongshuang Xu, Sze In Madeleine Ng, Wing Sze Chow, Yee Ka Wong, Yuchen Wang, Donger Lai, Zhongping Yao, Pui-Kin So, Jian Zhen Yu, and Man Nin Chan
Atmos. Chem. Phys., 22, 5685–5700, https://doi.org/10.5194/acp-22-5685-2022, https://doi.org/10.5194/acp-22-5685-2022, 2022
Short summary
Short summary
To date, while over a hundred organosulfates (OSs) have been detected in atmospheric aerosols, many of them are still unidentified, with unknown precursors and formation processes. We found the heterogeneous OH oxidation of an α-pinene-derived organosulfate (C10H17O5SNa, αpOS-249, αpOS-249) can proceed at an efficient rate and transform into more oxygenated OSs, which have been commonly detected in atmospheric aerosols and α-pinene-derived SOA in chamber studies.
Yee Ka Wong, Kin Man Liu, Claisen Yeung, Kenneth K. M. Leung, and Jian Zhen Yu
Atmos. Chem. Phys., 22, 5017–5031, https://doi.org/10.5194/acp-22-5017-2022, https://doi.org/10.5194/acp-22-5017-2022, 2022
Short summary
Short summary
Coarse particulate matter (PM) has been shown to cause adverse health impacts, but compared to PM2.5, the source of coarse PM is less studied through field measurements. We collected chemical composition data for coarse PM in Hong Kong for a 1-year period. Using statistical models, we found that regional transport of fugitive dust is responsible for the elevated coarse PM. This work sets an example of how field measurements can be effectively utilized for evidence-based policymaking.
Yao Wang, Yue Zhao, Yuchen Wang, Jian-Zhen Yu, Jingyuan Shao, Ping Liu, Wenfei Zhu, Zhen Cheng, Ziyue Li, Naiqiang Yan, and Huayun Xiao
Atmos. Chem. Phys., 21, 2959–2980, https://doi.org/10.5194/acp-21-2959-2021, https://doi.org/10.5194/acp-21-2959-2021, 2021
Short summary
Short summary
Organosulfates (OSs) are important constituents and tracers of secondary organic aerosols (SOAs) in the atmosphere. Here we characterized the OS species in ambient aerosols in Shanghai, China. We find that the contributions of OSs and SOAs to organic aerosols have increased in recent years and that OS production was largely controlled by the oxidant level (Ox), particularly in summer. We infer that mitigation of Ox pollution can effectively reduce the production of OSs and SOAs in eastern China.
Rui Li, Qiongqiong Wang, Xiao He, Shuhui Zhu, Kun Zhang, Yusen Duan, Qingyan Fu, Liping Qiao, Yangjun Wang, Ling Huang, Li Li, and Jian Zhen Yu
Atmos. Chem. Phys., 20, 12047–12061, https://doi.org/10.5194/acp-20-12047-2020, https://doi.org/10.5194/acp-20-12047-2020, 2020
Cited articles
Beelen, R., Hoek, G., van den Brandt, P. A, Goldbohm, R. A., Fischer, P.,
Schouten, L. J., Jerrett, M., Hughes, E., Armstrong, B., and Brunekreef, B.:
Long-term effects of traffic-related air pollution on mortality in a Dutch
cohort (NLCS-AIR Study), Environ. Health Persp., 116, 196–202, 2008.
Benbrahim-Tallaa, L., Baan, R. A., Grosse, Y., Lauby-Secretan, B., El
Ghissassi, F., Bouvard, V., Guha, N., Loomis, D., and Straif, K.:
Carcinogenicity of diesel-engine and gasoline-engine exhausts and some
nitroarenes, Lancet Oncol., 13, 663–664, 2012.
Bolden, A. L., Kwiatkowski, C. F., and Colborn, T.: New look at BTEX: Are
ambient levels a problem?, Environ. Sci. Technol., 49, 5261–5276, 2015.
Cheng, Y., Lee, S. C., Gu, Z. L., Ho, K. F., Zhang, Y. W., Huang, Y., Chow,
J. C., Watson, J. G., Cao, J. J., and Zhang, R. J.: PM2.5 and
PM10−2.5 chemical composition and source apportionment near a Hong Kong
roadway, Particuology, 18, 96–104, 2015.
Chow, J. C., Watson, J. G., Lowenthal, D. H., Chen, L. W. A., Zielinska, B., Mazzoleni, L. R., and Magliano, K. L.: Evaluation of organic markers for chemical mass balance source apportionment at the Fresno Supersite, Atmos. Chem. Phys., 7, 1741–1754, https://doi.org/10.5194/acp-7-1741-2007, 2007.
Chow, J. C., Watson, J. G., Lowenthal, D. H., Chen, L. W. A., and Motallebi,
N.: PM2.5 source profiles for black and organic carbon emission
inventories, Atmos. Environ., 45, 5407–5414, 2011.
Dallmann, T. R., Onasch, T. B., Kirchstetter, T. W., Worton, D. R., Fortner, E. C., Herndon, S. C., Wood, E. C., Franklin, J. P., Worsnop, D. R., Goldstein, A. H., and Harley, R. A.: Characterization of particulate matter emissions from on-road gasoline and diesel vehicles using a soot particle aerosol mass spectrometer, Atmos. Chem. Phys., 14, 7585–7599, https://doi.org/10.5194/acp-14-7585-2014, 2014.
Environment Bureau: A Clean Air Plan for Hong Kong, available at:
https://www.enb.gov.hk/en/files/New_Air_Plan_en.pdf (last access: 24 August 2020), 2013.
Environmental Protection Department: Air quality in Hong Kong 2017, The
Government of the Hong Kong Special Administrative Region, Hong Kong, 2018.
Gentner, D. R., Jathar, S. H., Gordon, T. D., Bahreini, R., Day, D. A., El
Haddad, I., Hayes, P. L., Pieber, S. M., Platt, S. M., de Gouw, J.,
Goldstein, A. H., Harley, R. A., Jimenez, J. L., Prévôt, A. S. H.,
and Robinson, A. L.: Review of urban secondary organic aerosol formation
from gasoline and diesel motor vehicle emissions, Environ. Sci. Technol.,
51, 1074–1093, 2017.
Gertler, A. W.: Diesel vs. gasoline emissions: Does PM from diesel or
gasoline vehicles dominate in the US?, Atmos. Environ., 39, 2349–2355, 2005.
Hagler, G. S. W., Bergin, M. H., Salmon, L. G., Yu, J. Z., Wan, E. C. H.,
Zheng, M., Zeng, L. M., Kiang, C. S., Zhang, Y. H., Lau, A. K. H., and
Schauer, J. J.: Source areas and chemical composition of fine particulate
matter in the Pearl River Delta region of China, Atmos. Environ., 40,
3802–3815, 2006.
He, Z., Wang, X., Ling, Z., Zhao, J., Guo, H., Shao, M., and Wang, Z.: Contributions of different anthropogenic volatile organic compound sources to ozone formation at a receptor site in the Pearl River Delta region and its policy implications, Atmos. Chem. Phys., 19, 8801–8816, https://doi.org/10.5194/acp-19-8801-2019, 2019.
Huang, X. H. H., Bian, Q. J., Louie, P. K. K., and Yu, J. Z.: Contributions of vehicular carbonaceous aerosols to PM2.5 in a roadside environment in Hong Kong, Atmos. Chem. Phys., 14, 9279–9293, https://doi.org/10.5194/acp-14-9279-2014, 2014.
Kelly, K. E., Kotchenruther, R., Kuprov, R., and Silcox, G. D.: Receptor
model source attributions for Utah's Salt Lake City airshed and the impacts
of wintertime secondary ammonium nitrate and ammonium chloride aerosol, J.
Air Waste Manage., 63, 575–590, 2013.
Kleeman, M. J., Schauer, J. J., and Cass, G. R.: Size and composition
distribution of fine particulate matter emitted from motor vehicles,
Environ. Sci. Technol., 34, 1132–1142, 2000.
Lambe, A. T., Logue, J. M., Kreisberg, N. M., Hering, S. V., Worton, D. R.,
Goldstein, A. H., Donahue, N. M., and Robinson, A. L.: Apportioning black
carbon to sources using highly time-resolved ambient measurements of organic
molecular markers in Pittsburgh, Atmos. Environ., 43, 3941–3950, 2009.
Lee, B. P., Li, Y. J., Yu, J. Z., Louie, P. K. K., and Chan, C. K.:
Characteristics of submicron particulate matter at the urban roadside in
downtown Hong Kong – Overview of 4 months of continuous high-resolution
aerosol mass spectrometer measurements, J. Geophys. Res.-Atmos., 120,
7040–7058, 2015.
Lee, B. P., Louie, P. K. K., Luk, C., and Chan, C. K.: Evaluation of traffic exhaust contributions to ambient carbonaceous submicron particulate matter in an urban roadside environment in Hong Kong, Atmos. Chem. Phys., 17, 15121–15135, https://doi.org/10.5194/acp-17-15121-2017, 2017.
Li, Y. C., Yu, J. Z., Ho, S. S. H., Yuan, Z. B., Lau, A. K. H., and Huang,
X. F.: Chemical characteristics of PM2.5 and organic aerosol source
analysis during cold front episodes in Hong Kong, China, Atmos. Res., 118,
41–51, 2012.
Lim, H. J. and Turpin, B. J.: Origins of primary and secondary organic
aerosol in Atlanta: results of time resolved measurements during the Atlanta
supersite experiment, Environ. Sci. Technol., 36, 4489–4496, 2002.
Louie, P. K. K., Watson, J. G., Chow, J. C., Chan, A., Sin, D. W. M., and
Lau, A. K. H.: Seasonal characteristics and regional transport of PM2.5
in Hong Kong, Atmos. Environ., 39, 1695–1710, 2005.
Lyu, X., Guo, H., Simpson, I. J., Meinardi, S., Louie, P. K. K., Ling, Z., Wang, Y., Liu, M., Luk, C. W. Y., Wang, N., and Blake, D. R.: Effectiveness of replacing catalytic converters in LPG-fueled vehicles in Hong Kong, Atmos. Chem. Phys., 16, 6609–6626, https://doi.org/10.5194/acp-16-6609-2016, 2016.
Norris, G., Duvall, R., Brown, S., and Bai, S.: EPA Positive Matrix
Factorization (PMF) 5.0 Fundamentals and User Guide, U.S. Environmental
Protection Agency, Washington, D.C., USA, 2014.
Paatero, P.: Least squares formulation of robust non-negative factor
analysis, Chemometr. Intell. Lab., 37, 23–35, 1997.
Paatero, P. and Tapper, U.: Positive matrix factorization: A non-negative
factor model with optimal utilization of error estimates of data values,
Environmetrics, 5, 111–126, 1994.
Peters, A., von Klot, S., Heier, M., Trentinaglia, I., Hörmann, A.,
Wichmann, H. E., and Löwel, H.: Exposure to traffic and the onset of
myocardial infarction, New Engl. J. Med., 351, 1721–1730, 2004.
Rice, M. B., Ljungman, P. L., Wilker, E. H., Dorans, K. S., Gold, D. R.,
Schwartz, J., Koutrakis, P., Washko, G. R., O'Connor, G. T., and Mittleman,
M. A.: Long-term exposure to traffic emissions and fine particulate matter
and lung function decline in the Framingham Heart Study, Am. J. Resp. Crit.
Care., 191, 656–664, 2015.
Robinson, A. L., Donahue, N. M., Shrivastava, M. K., Weitkamp, E. A., Sage,
A. M., Grieshop, A. P., Lane, T. E., Pierce, J. R., and Pandis, S. N.:
Rethinking organic aerosols: Semivolatile emissions and photochemical aging,
Science, 315, 1259–1262, 2007.
Schauer, J. J., Rogge, W. F., Hildemann, L., M., Mazurek, M. A., Cass, G.
R., and Simoneit, B. R. T.: Source apportionment of airborne particulate
matter using organic compounds as tracers, Atmos. Environ., 30, 3837–3855,
1996.
Subramanian, R., Donahue, N. M., Bernardo-Bricker, A., Rogge, W. F., and
Robinson, A. L.: Contribution of motor vehicle emissions to organic carbon
and fine particle mass in Pittsburgh, Pennsylvania: Effects of varying
source profiles and seasonal trends in ambient marker concentrations, Atmos.
Environ., 40, 8002–8019, 2006.
Sun, C., Lee, B. P., Huang, D., Jie Li, Y., Schurman, M. I., Louie, P. K. K., Luk, C., and Chan, C. K.: Continuous measurements at the urban roadside in an Asian megacity by Aerosol Chemical Speciation Monitor (ACSM): particulate matter characteristics during fall and winter seasons in Hong Kong, Atmos. Chem. Phys., 16, 1713–1728, https://doi.org/10.5194/acp-16-1713-2016, 2016.
Thornhill, D. A., Williams, A. E., Onasch, T. B., Wood, E., Herndon, S. C., Kolb, C. E., Knighton, W. B., Zavala, M., Molina, L. T., and Marr, L. C.: Application of positive matrix factorization to on-road measurements for source apportionment of diesel- and gasoline-powered vehicle emissions in Mexico City, Atmos. Chem. Phys., 10, 3629–3644, https://doi.org/10.5194/acp-10-3629-2010, 2010.
Transport Department: The Annual Traffic Census 2017, The Government of the
Hong Kong Special Administrative Region, Hong Kong, 2018.
Wang, X. L., Ho, K. F., Chow, J. C., Kohl, S. D., Chan, C. S., Cui, L., Lee,
S. C. F., Chen, L. W. A., Ho, S. S. H., Cheng, Y., and Watson, J. G.: Hong
Kong vehicle emission changes from 2003 to 2015 in the Shing Mun Tunnel,
Aerosol Sci. Technol., 52, 1085–1098, 2018.
Wang, Q. Q., He, X., Huang, X. H. H., Griffith, S. M., Feng, Y. M., Zhang,
T., Zhang, Q. Y., Wu, D., and Yu, J. Z.: Impact of secondary organic aerosol
tracers on tracer-based source apportionment of organic carbon and
PM2.5: A case study in the Pearl River Delta, China, ACS Earth Space
Chem., 1, 562–571, 2017.
Weitkamp, E. A., Lambe, A. T., Donahue, N. M., and Robinson, A. L.:
Laboratory measurements of the heterogeneous oxidation of condensed-phase
organic molecular makers for motor vehicle exhaust, Environ. Sci. Technol.,
42, 7950–7956, 2008.
Wong, Y. K., Huang, X. H. H., Cheng, Y. Y., Louie, P. K. K., Yu, A. L. C.,
Tang, A. W. Y., Chan, D. H. L., and Yu, J. Z.: Estimating contributions of
vehicular emissions to PM2.5 in a roadside environment: A multiple
approach study, Sci. Total Environ., 672, 776–788, 2019.
Wu, C. and Yu, J. Z.: Evaluation of linear regression techniques for atmospheric applications: the importance of appropriate weighting, Atmos. Meas. Tech., 11, 1233–1250, https://doi.org/10.5194/amt-11-1233-2018, 2018.
Yao, D. W., Lyu, X. P., Murray, F., Morawska, L., Yu, W., Wang, J. Y., and
Guo, H.: Continuous effectiveness of replacing catalytic converters on
liquefied petroleum gas-fueled vehicles in Hong Kong, Sci. Total Environ.,
648, 830–838, 2019.
Yu, J. Z. and Zhang, T.: Chemical speciation of PM2.5 filter samples –
January 1 through December 31, 2017, Final report submitted to the Hong Kong
Environmental Protection Department, The Government of the Hong Kong Special
Administrative Region (Ref. 16-02709), Hong Kong, 2018.
Yu, J. Z., Huang, X. H. H., Griffith, S. M., Yuan, Z. B., and Ng, W. M.:
Integrated assessment on roadside air quality, Final report submitted to the
Hong Kong Environmental Protection Department, The Government of the Hong
Kong Special Administrative Region (Ref. 12-00255), Hong Kong, 2016.
Zheng, M., Hagler, G. S. W., Ke, L., Bergin, M. H., Wang, F., Louie, P. K.
K., Salmon, L., Sin, D. W. M., Yu, J. Z., and Schauer, J. J.: Composition
and sources of carbonaceous aerosols at three contrasting sites in Hong
Kong, J. Geophys. Res., 111, D20313, https://doi.org/10.1029/2006JD007074, 2006.
Short summary
We present an approach to track separate contributions to PM2.5 by gasoline and diesel vehicles through a positive matrix factorization analysis of online monitoring data measurable by relatively inexpensive analytical instruments. They are PM2.5 organic and elemental carbon, C2–C9 volatile organic compounds, and nitrogen oxide concentrations. The method was demonstrated to be effective by applying monitoring data spanning 6 years (2011–2017) from a roadside environment in Hong Kong.
We present an approach to track separate contributions to PM2.5 by gasoline and diesel vehicles...
Altmetrics
Final-revised paper
Preprint