Articles | Volume 26, issue 5
https://doi.org/10.5194/acp-26-3589-2026
© Author(s) 2026. 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-26-3589-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 Mar 2026
Research article |
| 10 Mar 2026
| 10 Mar 2026
Degradation of anhydro-saccharides and the driving factors in real atmospheric conditions: a cross-city study in China
Biao Zhou
School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
Kun Zhang
School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
Qiongqiong Wang
Department of Atmospheric Science, School of Environmental Studies, China University of Geosciences, Wuhan, China
Jiqi Zhu
School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China
Department of Chemistry, The Hong Kong University of Science & Technology, Hong Kong, China
Division of Environment & Sustainability, The Hong Kong University of Science & Technology, Hong Kong, China
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Yan Zhang, Jiani Tan, Qing Mu, Joshua S. Fu, and Li Li
EGUsphere, https://doi.org/10.5194/egusphere-2025-6160, https://doi.org/10.5194/egusphere-2025-6160, 2026
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
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Despite growing use of machine learning in environmental research, few have studied how input data affects findings. We examined the impact of input data characteristics on nitrogen deposition estimates in East and Southeast Asia. Insufficient sample size cuts accuracy by up to 12 %, while data-scarce and remote areas show up to 50 % bias due to poor training data representation. We created a transferable framework for uncertainty quantification, applicable to other data-scarce geospatial tasks.
Ningning Sun, Xu Yu, Jian Zhen Yu, Bo Zhang, Yilan Li, Ye Hu, Zhe Li, Zhenlou Chen, and Guitao Shi
Atmos. Chem. Phys., 26, 1699–1712, https://doi.org/10.5194/acp-26-1699-2026, https://doi.org/10.5194/acp-26-1699-2026, 2026
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Atmospheric particles over the ocean contain organic nitrogen, affecting climate and ecosystems. This first pole-to-pole study of marine air reveals a strong latitudinal divide, with higher concentrations in the polluted Northern Hemisphere. A key discovery is that air influenced by Antarctic sea ice is enriched in organic nitrogen, revealing a major natural source. Our new dataset improves climate models by clarifying how human emissions and natural processes shape the atmosphere.
Xueying Liu, Yeqi Huang, Yao Chen, Xin Feng, Jiading Li, 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
Atmos. Chem. Phys., 25, 17629–17649, https://doi.org/10.5194/acp-25-17629-2025, https://doi.org/10.5194/acp-25-17629-2025, 2025
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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.
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
Atmos. Chem. Phys., 25, 12585–12598, https://doi.org/10.5194/acp-25-12585-2025, https://doi.org/10.5194/acp-25-12585-2025, 2025
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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 the marine boundary layer.
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
Atmos. Chem. Phys., 25, 12569–12584, https://doi.org/10.5194/acp-25-12569-2025, https://doi.org/10.5194/acp-25-12569-2025, 2025
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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.
Qingfang Su, Yifei Chen, Yangjun Wang, David C. Wong, Havala O. T. Pye, Ling Huang, Golam Sarwar, Benjamin Murphy, Bryan Place, and Li Li
EGUsphere, https://doi.org/10.5194/egusphere-2025-3627, https://doi.org/10.5194/egusphere-2025-3627, 2025
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This study evaluated the PM2.5 simulation by the latest CRACMM mechanism coupled with CMAQ, covering different seasons and specific regions over China. Results derived by CRACMM are compared with two well-established chemical mechanisms, Saprc07 and CB6. Differences in PM2.5 and SOA drivers between CRACMM and the two existing mechanisms are further explored. Results provide a solid foundation for the further application of CRACMM in understanding and regulating air pollution globally.
Ling Huang, Benjie Chen, Zi'ang Wu, Katie Tuite, Pradeepa Vennam, Greg Yarwood, and Li Li
EGUsphere, https://doi.org/10.5194/egusphere-2025-3921, https://doi.org/10.5194/egusphere-2025-3921, 2025
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Secondary organic aerosol (SOA) constitutes a major component of atmospheric aerosol that models must account for to assess how human activities influence air quality, climate, and public health. We find substantial differences in how current air quality models represent SOA highlighting a lack of consensus within the modelling community. Our findings emphasize the need to recognize the limitations of current SOA schemes in the context of air quality management and policy development.
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
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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.
Jingwen Dai, Kun Zhang, Yanli Feng, Xin Yi, Rui Li, Jin Xue, Qing Li, Lishu Shi, Jiaqiang Liao, Yanan Yi, Fangting Wang, Liumei Yang, Hui Chen, Ling Huang, Jiani Tan, Yangjun Wang, and Li Li
Atmos. Chem. Phys., 25, 7467–7484, https://doi.org/10.5194/acp-25-7467-2025, https://doi.org/10.5194/acp-25-7467-2025, 2025
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Oxygenated volatile organic compounds (OVOCs) are important ozone (O3) precursors. However, most O3 formation analysis based on the box model (OBM) does not include any OVOC constraint. To access the interference of OVOCs with O3 simulation, this study presents results from a field campaign and OBM analysis. Our results indicate that no OVOC constraint in the OBM can lead to overestimation of OVOCs, free radicals, and O3.
Ling Huang, Xinxin Zhang, Chris Emery, Qing Mu, Greg Yarwood, Hehe Zhai, Zhixu Sun, Shuhui Xue, Yangjun Wang, Joshua S. Fu, and Li Li
Atmos. Chem. Phys., 25, 4233–4249, https://doi.org/10.5194/acp-25-4233-2025, https://doi.org/10.5194/acp-25-4233-2025, 2025
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Ground-level ozone pollution has emerged as a significant air pollutant in China. Chemical transport models (CTMs) serve as crucial tools in addressing ozone pollution. This study reviews CTM applications for simulating ozone in China and proposes goal and criteria benchmark values for evaluating ozone. Along with prior work on PM₂₅ and other pollutants, this effort establishes a comprehensive framework for evaluating CTM performance in China.
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
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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.
Xiao He, Xuan Zheng, Shuwen Guo, Lewei Zeng, Ting Chen, Bohan Yang, Shupei Xiao, Qiongqiong Wang, Zhiyuan Li, Yan You, Shaojun Zhang, and Ye Wu
Atmos. Chem. Phys., 24, 10655–10666, https://doi.org/10.5194/acp-24-10655-2024, https://doi.org/10.5194/acp-24-10655-2024, 2024
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This study introduces an innovative method for identifying and quantifying complex organic vapors and aerosols. By combining advanced analytical techniques and new algorithms, we categorized thousands of compounds from heavy-duty diesel vehicles and ambient air and highlighted specific tracers for emission sources. The innovative approach enhances peak identification, reduces quantification uncertainties, and offers new insights for air quality management and atmospheric chemistry.
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
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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
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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.
Ling Huang, Jiong Fang, Jiaqiang Liao, Greg Yarwood, Hui Chen, Yangjun Wang, and Li Li
Atmos. Chem. Phys., 23, 14919–14932, https://doi.org/10.5194/acp-23-14919-2023, https://doi.org/10.5194/acp-23-14919-2023, 2023
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Surface ozone concentrations have emerged as a major environmental issue in China. Although control strategies aimed at reducing NOx emissions from conventional combustion sources are widely recognized, soil NOx emissions have received little attention. The impact of soil NO emissions on ground-level ozone concentration is yet to be evaluated. In this study, we estimated the soil NO emissions and evaluated its impact on ozone formation in China.
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
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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
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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
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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.
Ling Huang, Hanqing Liu, Greg Yarwood, Gary Wilson, Jun Tao, Zhiwei Han, Dongsheng Ji, Yangjun Wang, and Li Li
EGUsphere, https://doi.org/10.5194/egusphere-2022-1502, https://doi.org/10.5194/egusphere-2022-1502, 2023
Preprint archived
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Secondary organic aerosols are an important component of PM2.5, with contributions from anthropogenic, biogenic volatile organic compounds, semi- and intermediate volatility organic compounds. Policy makers need to know which SOA precursors are important. We investigated the role of different SOA precursors and SOA algorithms by applying two commonly used models, CAMx and CMAQ. Suggestions for SOA modelling and control are provided.
Yibei Wan, Xiangpeng Huang, Chong Xing, Qiongqiong Wang, Xinlei Ge, and Huan Yu
Atmos. Chem. Phys., 22, 15413–15423, https://doi.org/10.5194/acp-22-15413-2022, https://doi.org/10.5194/acp-22-15413-2022, 2022
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The organic compounds involved in continental new particle formation have been investigated in depth in the last 2 decades. In contrast, no prior work has studied the exact chemical composition of organic compounds and their role in coastal new particle formation. We present a complementary study to the ongoing laboratory and field research on iodine nucleation in the coastal atmosphere. This study provided a more complete story of coastal I-NPF from low-tide macroalgal emission.
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
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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
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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
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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
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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.
Kun Zhang, Zhiqiang Liu, Xiaojuan Zhang, Qing Li, Andrew Jensen, Wen Tan, Ling Huang, Yangjun Wang, Joost de Gouw, and Li Li
Atmos. Chem. Phys., 22, 4853–4866, https://doi.org/10.5194/acp-22-4853-2022, https://doi.org/10.5194/acp-22-4853-2022, 2022
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A significant increase in O3 concentrations was found during the lockdown period of COVID-19 in most areas of China. By field measurements coupled with machine learning, an observation-based model (OBM) and sensitivity analysis, we found the changes in the NOx / VOC ratio were a key reason for the significant rise in O3. To restrain O3 pollution, more efforts should be devoted to the control of anthropogenic OVOCs, alkenes and aromatics.
Kun Zhang, Ling Huang, Qing Li, Juntao Huo, Yusen Duan, Yuhang Wang, Elly Yaluk, Yangjun Wang, Qingyan Fu, and Li Li
Atmos. Chem. Phys., 21, 5905–5917, https://doi.org/10.5194/acp-21-5905-2021, https://doi.org/10.5194/acp-21-5905-2021, 2021
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Recently, high O3 concentrations were frequently observed in rural areas of the Yangtze River Delta (YRD) region under stagnant conditions. Using an online measurement and observation-based model, we investigated the budget of ROx radicals and the influence of isoprene chemistry on O3 formation. Our results underline that isoprene chemistry in the rural atmosphere becomes important with the participation of anthropogenic NOx.
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Short summary
Anhydro-saccharides are key organic markers for biomass burning, but their decay rates and driving factors in real ambient environments remain unclear. This study conducted an online field measurement of PM₂.₅-bound saccharides in three eastern Chinese cities. Daytime levoglucosan decay rates were calculated, and the driving factors were investigated using a machine learning model. Findings of this study offers a strong scientific basis to support air pollution management.
Anhydro-saccharides are key organic markers for biomass burning, but their decay rates and...
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