Articles | Volume 21, issue 11
https://doi.org/10.5194/acp-21-9089-2021
© Author(s) 2021. 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-21-9089-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Jun 2021
Research article |
| 15 Jun 2021
| 15 Jun 2021
Urban organic aerosol composition in eastern China differs from north to south: molecular insight from a liquid chromatography–mass spectrometry (Orbitrap) study
State Key Laboratory of Loess and Quaternary Geology (SKLLQG), Center
for Excellence in Quaternary Science and Global Change, and Key Laboratory
of Aerosol Chemistry and Physics, Institute of Earth and Environment,
Chinese Academy of Sciences, Xi'an 710061, China
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg
University Mainz, Duesbergweg 10–14, Mainz 55128, Germany
Department of Chemistry, Aarhus University, Langelandsgade 140,
8000 Aarhus C, Denmark
Ru-Jin Huang
CORRESPONDING AUTHOR
State Key Laboratory of Loess and Quaternary Geology (SKLLQG), Center
for Excellence in Quaternary Science and Global Change, and Key Laboratory
of Aerosol Chemistry and Physics, Institute of Earth and Environment,
Chinese Academy of Sciences, Xi'an 710061, China
Open Studio for Oceanic-Continental Climate and Environment Changes,
Pilot National Laboratory for Marine Science and Technology (Qingdao),
Qingdao 266061, China
Martin Brüggemann
Atmospheric Chemistry Department (ACD), Leibniz Institute for
Tropospheric Research (TROPOS), Permoserstraße 15, 04318 Leipzig,
Germany
Yun Zhang
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg
University Mainz, Duesbergweg 10–14, Mainz 55128, Germany
Lu Yang
State Key Laboratory of Loess and Quaternary Geology (SKLLQG), Center
for Excellence in Quaternary Science and Global Change, and Key Laboratory
of Aerosol Chemistry and Physics, Institute of Earth and Environment,
Chinese Academy of Sciences, Xi'an 710061, China
Haiyan Ni
State Key Laboratory of Loess and Quaternary Geology (SKLLQG), Center
for Excellence in Quaternary Science and Global Change, and Key Laboratory
of Aerosol Chemistry and Physics, Institute of Earth and Environment,
Chinese Academy of Sciences, Xi'an 710061, China
Jie Guo
State Key Laboratory of Loess and Quaternary Geology (SKLLQG), Center
for Excellence in Quaternary Science and Global Change, and Key Laboratory
of Aerosol Chemistry and Physics, Institute of Earth and Environment,
Chinese Academy of Sciences, Xi'an 710061, China
Meng Wang
State Key Laboratory of Loess and Quaternary Geology (SKLLQG), Center
for Excellence in Quaternary Science and Global Change, and Key Laboratory
of Aerosol Chemistry and Physics, Institute of Earth and Environment,
Chinese Academy of Sciences, Xi'an 710061, China
Jiajun Han
Department of Chemistry, University of Toronto, 80 St. George Street,
M5S3H6 Toronto, Canada
Merete Bilde
Department of Chemistry, Aarhus University, Langelandsgade 140,
8000 Aarhus C, Denmark
Marianne Glasius
Department of Chemistry, Aarhus University, Langelandsgade 140,
8000 Aarhus C, Denmark
Thorsten Hoffmann
CORRESPONDING AUTHOR
Institute of Inorganic and Analytical Chemistry, Johannes Gutenberg
University Mainz, Duesbergweg 10–14, Mainz 55128, Germany
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Yuquan Gong, Ru-Jin Huang, Lu Yang, Ting Wang, Wei Yuan, Wei Xu, Wenjuan Cao, Yang Wang, and Yongjie Li
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Dimitri Castarède, Zoé Brasseur, Yusheng Wu, Zamin A. Kanji, Markus Hartmann, Lauri Ahonen, Merete Bilde, Markku Kulmala, Tuukka Petäjä, Jan B. C. Pettersson, Berko Sierau, Olaf Stetzer, Frank Stratmann, Birgitta Svenningsson, Erik Swietlicki, Quynh Thu Nguyen, Jonathan Duplissy, and Erik S. Thomson
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Julia Homann, Niklas Karbach, Stacy A. Carolin, Daniel H. James, David Hodell, Sebastian F. M. Breitenbach, Ola Kwiecien, Mark Brenner, Carlos Peraza Lope, and Thorsten Hoffmann
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Cave stalagmites contain substances that can be used to reconstruct past changes in local and regional environmental conditions. We used two classes of biomarkers (polycyclic aromatic hydrocarbons and monosaccharide anhydrides) to detect the presence of fire and to also explore changes in fire regime (e.g. fire frequency, intensity, and fuel source). We tested our new method on a stalagmite from Mayapan, a large Maya city on the Yucatán Peninsula.
Yifang Gu, Ru-Jin Huang, Jing Duan, Wei Xu, Chunshui Lin, Haobin Zhong, Ying Wang, Haiyan Ni, Quan Liu, Ruiguang Xu, Litao Wang, and Yong Jie Li
Atmos. Chem. Phys., 23, 5419–5433, https://doi.org/10.5194/acp-23-5419-2023, https://doi.org/10.5194/acp-23-5419-2023, 2023
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Secondary organic aerosol (SOA) can be produced by various pathways, but its formation mechanisms are unclear. Observations were conducted in the North China Plain during a highly oxidizing atmosphere in summer. We found that fast photochemistry dominated SOA formation during daytime. Two types of aqueous-phase chemistry (nocturnal and daytime processing) take place at high relative humidity. The potential transformation from primary organic aerosol (POA) to SOA was also an important pathway.
Chunshui Lin, Ru-Jin Huang, Haobin Zhong, Jing Duan, Zixi Wang, Wei Huang, and Wei Xu
Atmos. Chem. Phys., 23, 3595–3607, https://doi.org/10.5194/acp-23-3595-2023, https://doi.org/10.5194/acp-23-3595-2023, 2023
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The complex interaction between O3 and PM2.5, coupled with the topology of the Fenwei Plain and the evolution of the boundary layer height, highlights the challenges in further reducing particulate pollution in winter despite years of efforts to reduce emissions. Through scenario analysis in a chemical box model constrained by observation, we show the co-benefits of reducing NOx and VOCs simultaneously in reducing ozone and SOA.
Huanhuan Zhang, Rui Li, Chengpeng Huang, Xiaofei Li, Shuwei Dong, Fu Wang, Tingting Li, Yizhu Chen, Guohua Zhang, Yan Ren, Qingcai Chen, Ru-jin Huang, Siyu Chen, Tao Xue, Xinming Wang, and Mingjin Tang
Atmos. Chem. Phys., 23, 3543–3559, https://doi.org/10.5194/acp-23-3543-2023, https://doi.org/10.5194/acp-23-3543-2023, 2023
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This work investigated the seasonal variation of aerosol Fe solubility for coarse and fine particles in Xi’an, a megacity in northwestern China severely affected by anthropogenic emission and desert dust aerosol. In addition, we discussed in depth what controlled aerosol Fe solubility at different seasons for coarse and fine particles.
Denis Leppla, Nora Zannoni, Leslie Kremper, Jonathan Williams, Christopher Pöhlker, Marta Sá, Maria Christina Solci, and Thorsten Hoffmann
Atmos. Chem. Phys., 23, 809–820, https://doi.org/10.5194/acp-23-809-2023, https://doi.org/10.5194/acp-23-809-2023, 2023
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Chiral chemodiversity plays a critical role in biochemical processes such as insect and plant communication. Here we report on the measurement of chiral-specified secondary organic aerosol in the Amazon rainforest. The results show that the chiral ratio is mainly determined by large-scale emission processes. Characteristic emissions of chiral aerosol precursors from different forest ecosystems can thus provide large-scale information on different biogenic sources via chiral particle analysis.
Yunfan Liu, Hang Su, Siwen Wang, Chao Wei, Wei Tao, Mira L. Pöhlker, Christopher Pöhlker, Bruna A. Holanda, Ovid O. Krüger, Thorsten Hoffmann, Manfred Wendisch, Paulo Artaxo, Ulrich Pöschl, Meinrat O. Andreae, and Yafang Cheng
Atmos. Chem. Phys., 23, 251–272, https://doi.org/10.5194/acp-23-251-2023, https://doi.org/10.5194/acp-23-251-2023, 2023
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The origins of the abundant cloud condensation nuclei (CCN) in the upper troposphere (UT) of the Amazon remain unclear. With model developments of new secondary organic aerosol schemes and constrained by observation, we show that strong aerosol nucleation and condensation in the UT is triggered by biogenic organics, and organic condensation is key for UT CCN production. This UT CCN-producing mechanism may prevail over broader vegetation canopies and deserves emphasis in aerosol–climate feedback.
Bernadette Rosati, Sini Isokääntä, Sigurd Christiansen, Mads Mørk Jensen, Shamjad P. Moosakutty, Robin Wollesen de Jonge, Andreas Massling, Marianne Glasius, Jonas Elm, Annele Virtanen, and Merete Bilde
Atmos. Chem. Phys., 22, 13449–13466, https://doi.org/10.5194/acp-22-13449-2022, https://doi.org/10.5194/acp-22-13449-2022, 2022
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Sulfate aerosols have a strong influence on climate. Due to the reduction in sulfur-based fossil fuels, natural sulfur emissions play an increasingly important role. Studies investigating the climate relevance of natural sulfur aerosols are scarce. We study the water uptake of such particles in the laboratory, demonstrating a high potential to take up water and form cloud droplets. During atmospheric transit, chemical processing affects the particles’ composition and thus their water uptake.
Meng Wang, Yusen Duan, Wei Xu, Qiyuan Wang, Zhuozhi Zhang, Qi Yuan, Xinwei Li, Shuwen Han, Haijie Tong, Juntao Huo, Jia Chen, Shan Gao, Zhongbiao Wu, Long Cui, Yu Huang, Guangli Xiu, Junji Cao, Qingyan Fu, and Shun-cheng Lee
Atmos. Chem. Phys., 22, 12789–12802, https://doi.org/10.5194/acp-22-12789-2022, https://doi.org/10.5194/acp-22-12789-2022, 2022
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In this study, we report the long-term measurement of organic carbon (OC) and elementary carbon (EC) in PM2.5 with hourly time resolution conducted at a regional site in Shanghai from 2016 to 2020. The results from this study provide critical information about the long-term trend of carbonaceous aerosol, in particular secondary OC, in one of the largest megacities in the world and are helpful for developing pollution control measures from a long-term planning perspective.
Jing Duan, Ru-Jin Huang, Yifang Gu, Chunshui Lin, Haobin Zhong, Wei Xu, Quan Liu, Yan You, Jurgita Ovadnevaite, Darius Ceburnis, Thorsten Hoffmann, and Colin O'Dowd
Atmos. Chem. Phys., 22, 10139–10153, https://doi.org/10.5194/acp-22-10139-2022, https://doi.org/10.5194/acp-22-10139-2022, 2022
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Biomass-burning-influenced oxygenated organic aerosol (OOA-BB), formed from the photochemical oxidation and aging of biomass burning OA (BBOA), was resolved in urban Xi’an. The aqueous-phase processed oxygenated OA (aq-OOA) concentration was more dependent on secondary inorganic aerosol (SIA) content and aerosol liquid water content (ALWC). The increased aq-OOA contribution during SIA-enhanced periods likely reflects OA evolution due to the addition of alcohol or peroxide groups
Haobin Zhong, Ru-Jin Huang, Chunshui Lin, Wei Xu, Jing Duan, Yifang Gu, Wei Huang, Haiyan Ni, Chongshu Zhu, Yan You, Yunfei Wu, Renjian Zhang, Jurgita Ovadnevaite, Darius Ceburnis, and Colin D. O'Dowd
Atmos. Chem. Phys., 22, 9513–9524, https://doi.org/10.5194/acp-22-9513-2022, https://doi.org/10.5194/acp-22-9513-2022, 2022
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To investigate the physico-chemical properties of aerosol transported from major pollution regions in China, observations were conducted ~200 m above the ground at the junction location of the two key pollution areas. We found that the formation efficiency, oxidation state and production rate of secondary aerosol were different in the transport sectors from different pollution regions, and they were largely enhanced by the regional long-distance transport.
Alexandra Gutmann, Nicole Bobrowski, Marcello Liotta, and Thorsten Hoffmann
Atmos. Meas. Tech., 14, 6395–6406, https://doi.org/10.5194/amt-14-6395-2021, https://doi.org/10.5194/amt-14-6395-2021, 2021
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Motivated by a special interest in bromine chemistry in volcanic plumes, the study presented here describes a new method for the quantitative collection of gaseous hydrogen bromide in gas diffusion denuders. The hydrogen bromide reacted during sampling with appropriate epoxides applied to the denuder walls. The denuder sampling assembly was successfully deployed in the volcanic plume of Masaya volcano, Nicaragua.
Henrieka Detlef, Brendan Reilly, Anne Jennings, Mads Mørk Jensen, Matt O'Regan, Marianne Glasius, Jesper Olsen, Martin Jakobsson, and Christof Pearce
The Cryosphere, 15, 4357–4380, https://doi.org/10.5194/tc-15-4357-2021, https://doi.org/10.5194/tc-15-4357-2021, 2021
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Here we examine the Nares Strait sea ice dynamics over the last 7000 years and their implications for the late Holocene readvance of the floating part of Petermann Glacier. We propose that the historically observed sea ice dynamics are a relatively recent feature, while most of the mid-Holocene was marked by variable sea ice conditions in Nares Strait. Nonetheless, major advances of the Petermann ice tongue were preceded by a shift towards harsher sea ice conditions in Nares Strait.
Louise N. Jensen, Manjula R. Canagaratna, Kasper Kristensen, Lauriane L. J. Quéléver, Bernadette Rosati, Ricky Teiwes, Marianne Glasius, Henrik B. Pedersen, Mikael Ehn, and Merete Bilde
Atmos. Chem. Phys., 21, 11545–11562, https://doi.org/10.5194/acp-21-11545-2021, https://doi.org/10.5194/acp-21-11545-2021, 2021
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This work targets the chemical composition of α-pinene-derived secondary organic aerosol (SOA) formed in the temperature range from -15 to 20°C. Experiments were conducted in an atmospheric simulation chamber. Positive matrix factorization analysis of data obtained by a high-resolution time-of-flight aerosol mass spectrometer shows that the elemental aerosol composition is controlled by the initial α-pinene concentration and temperature during SOA formation.
Haijie Tong, Fobang Liu, Alexander Filippi, Jake Wilson, Andrea M. Arangio, Yun Zhang, Siyao Yue, Steven Lelieveld, Fangxia Shen, Helmi-Marja K. Keskinen, Jing Li, Haoxuan Chen, Ting Zhang, Thorsten Hoffmann, Pingqing Fu, William H. Brune, Tuukka Petäjä, Markku Kulmala, Maosheng Yao, Thomas Berkemeier, Manabu Shiraiwa, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 10439–10455, https://doi.org/10.5194/acp-21-10439-2021, https://doi.org/10.5194/acp-21-10439-2021, 2021
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We measured radical yields of aqueous PM2.5 extracts and found lower yields at higher concentrations of PM2.5. Abundances of water-soluble transition metals and aromatics in PM2.5 were positively correlated with the relative fraction of •OH but negatively correlated with the relative fraction of C-centered radicals among detected radicals. Composition-dependent reactive species yields may explain differences in the reactivity and health effects of PM2.5 in clean versus polluted air.
Robin Wollesen de Jonge, Jonas Elm, Bernadette Rosati, Sigurd Christiansen, Noora Hyttinen, Dana Lüdemann, Merete Bilde, and Pontus Roldin
Atmos. Chem. Phys., 21, 9955–9976, https://doi.org/10.5194/acp-21-9955-2021, https://doi.org/10.5194/acp-21-9955-2021, 2021
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This study presents a detailed analysis of the OH-initiated oxidation of dimethyl sulfide (DMS) based on experiments performed in the Aarhus University Research on Aerosol (AURA) smog chamber and the gas- and particle-phase chemistry kinetic multilayer model (ADCHAM). We capture the formation, growth and chemical composition of aerosols in the chamber setup by an improved multiphase oxidation mechanism and utilize our results to reproduce the important role of DMS in the marine boundary layer.
Yandong Tong, Veronika Pospisilova, Lu Qi, Jing Duan, Yifang Gu, Varun Kumar, Pragati Rai, Giulia Stefenelli, Liwei Wang, Ying Wang, Haobin Zhong, Urs Baltensperger, Junji Cao, Ru-Jin Huang, André S. H. Prévôt, and Jay G. Slowik
Atmos. Chem. Phys., 21, 9859–9886, https://doi.org/10.5194/acp-21-9859-2021, https://doi.org/10.5194/acp-21-9859-2021, 2021
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We investigate SOA sources and formation processes by a field deployment of the EESI-TOF-MS and L-TOF AMS in Beijing in late autumn and early winter. Our study shows that the sources and processes giving rise to haze events in Beijing are variable and seasonally dependent: (1) in the heating season, SOA formation is driven by oxidation of aromatics from solid fuel combustion; and (2) under high-NOx and RH conditions, aqueous-phase chemistry can be a major contributor to SOA formation.
Bo Galle, Santiago Arellano, Nicole Bobrowski, Vladimir Conde, Tobias P. Fischer, Gustav Gerdes, Alexandra Gutmann, Thorsten Hoffmann, Ima Itikarai, Tomas Krejci, Emma J. Liu, Kila Mulina, Scott Nowicki, Tom Richardson, Julian Rüdiger, Kieran Wood, and Jiazhi Xu
Atmos. Meas. Tech., 14, 4255–4277, https://doi.org/10.5194/amt-14-4255-2021, https://doi.org/10.5194/amt-14-4255-2021, 2021
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Measurements of volcanic gases are important for geophysical research, risk assessment and environmental impact studies. Some gases, like SO2 and BrO, may be studied from the ground at a safe distance using remote sensing techniques. Many other gases require in situ access to the gas plume. Here, a drone may be an attractive alternative. This paper describes a drone specially adapted for volcanic gas studies and demonstrates its use in a field campaign at Manam volcano in Papua New Guinea.
Wei Xu, Kirsten N. Fossum, Jurgita Ovadnevaite, Chunshui Lin, Ru-Jin Huang, Colin O'Dowd, and Darius Ceburnis
Atmos. Chem. Phys., 21, 8655–8675, https://doi.org/10.5194/acp-21-8655-2021, https://doi.org/10.5194/acp-21-8655-2021, 2021
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Cloud condensation nuclei (CCN) are an important topic in atmospheric studies, especially for evaluating the climate impact of aerosol. Here in this study, CCN closure is studied by using chemical composition based on an aerosol mass spectrometer (AMS) and hygroscopicity growth measurements based on a humidified tandem differential mobility analyzer (HTDMA) at the Mace Head atmospheric research station.
Chao Peng, Patricia N. Razafindrambinina, Kotiba A. Malek, Lanxiadi Chen, Weigang Wang, Ru-Jin Huang, Yuqing Zhang, Xiang Ding, Maofa Ge, Xinming Wang, Akua A. Asa-Awuku, and Mingjin Tang
Atmos. Chem. Phys., 21, 7135–7148, https://doi.org/10.5194/acp-21-7135-2021, https://doi.org/10.5194/acp-21-7135-2021, 2021
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Organosulfates are important constituents in tropospheric aerosol particles, but their hygroscopic properties and cloud condensation nuclei activities are not well understood. In our work, three complementary techniques were employed to investigate the interactions of 11 organosulfates with water vapor under sub- and supersaturated conditions.
Inken Heidke, Adam Hartland, Denis Scholz, Andrew Pearson, John Hellstrom, Sebastian F. M. Breitenbach, and Thorsten Hoffmann
Biogeosciences, 18, 2289–2300, https://doi.org/10.5194/bg-18-2289-2021, https://doi.org/10.5194/bg-18-2289-2021, 2021
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We analyzed lignin oxidation products (LOPs) in leaf litter and different soil horizons as well as dripwater and flowstone samples from four different cave sites from different vegetation zones in New Zealand using liquid chromatography coupled to mass spectrometry. We test whether the original source-dependent LOP signal of the overlying vegetation is preserved and can be recovered from flowstone samples and investigate how the signal is altered by the transport from the soil to the cave.
Wei Yuan, Ru-Jin Huang, Lu Yang, Ting Wang, Jing Duan, Jie Guo, Haiyan Ni, Yang Chen, Qi Chen, Yongjie Li, Ulrike Dusek, Colin O'Dowd, and Thorsten Hoffmann
Atmos. Chem. Phys., 21, 3685–3697, https://doi.org/10.5194/acp-21-3685-2021, https://doi.org/10.5194/acp-21-3685-2021, 2021
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We characterized the seasonal variations in nitrated aromatic compounds (NACs) in composition, sources, and their light absorption contribution to brown carbon (BrC) aerosol in Xi'an, Northwest China. Our results show that secondary formation and vehicular emission were dominant sources in summer (~80 %), and biomass burning and coal combustion were major sources in winter (~75 %), and they indicate that the composition and sources of NACs have a profound impact on the light absorption of BrC
Julian Rüdiger, Alexandra Gutmann, Nicole Bobrowski, Marcello Liotta, J. Maarten de Moor, Rolf Sander, Florian Dinger, Jan-Lukas Tirpitz, Martha Ibarra, Armando Saballos, María Martínez, Elvis Mendoza, Arnoldo Ferrufino, John Stix, Juan Valdés, Jonathan M. Castro, and Thorsten Hoffmann
Atmos. Chem. Phys., 21, 3371–3393, https://doi.org/10.5194/acp-21-3371-2021, https://doi.org/10.5194/acp-21-3371-2021, 2021
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We present an innovative approach to study halogen chemistry in the plume of Masaya volcano in Nicaragua. An unique data set was collected using multiple techniques, including drones. These data enabled us to determine the fraction of activation of the respective halogens at various plume ages, where in-mixing of ambient air causes chemical reactions. An atmospheric chemistry box model was employed to further examine the field results and help our understanding of volcanic plume chemistry.
Francesco Canonaco, Anna Tobler, Gang Chen, Yulia Sosedova, Jay Gates Slowik, Carlo Bozzetti, Kaspar Rudolf Daellenbach, Imad El Haddad, Monica Crippa, Ru-Jin Huang, Markus Furger, Urs Baltensperger, and André Stephan Henry Prévôt
Atmos. Meas. Tech., 14, 923–943, https://doi.org/10.5194/amt-14-923-2021, https://doi.org/10.5194/amt-14-923-2021, 2021
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Long-term ambient aerosol mass spectrometric data were analyzed with a statistical model (PMF) to obtain source contributions and fingerprints. The new aspects of this paper involve time-dependent source fingerprints by a rolling technique and the replacement of the full visual inspection of each run by a user-defined set of criteria to monitor the quality of each of these runs more efficiently. More reliable sources will finally provide better instruments for political mitigation strategies.
Pragati Rai, Jay G. Slowik, Markus Furger, Imad El Haddad, Suzanne Visser, Yandong Tong, Atinderpal Singh, Günther Wehrle, Varun Kumar, Anna K. Tobler, Deepika Bhattu, Liwei Wang, Dilip Ganguly, Neeraj Rastogi, Ru-Jin Huang, Jaroslaw Necki, Junji Cao, Sachchida N. Tripathi, Urs Baltensperger, and André S. H. Prévôt
Atmos. Chem. Phys., 21, 717–730, https://doi.org/10.5194/acp-21-717-2021, https://doi.org/10.5194/acp-21-717-2021, 2021
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We present a simple conceptual framework based on elemental size distributions and enrichment factors that allows for a characterization of major sources, site-to-site similarities, and local differences and the identification of key information required for efficient policy development. Absolute concentrations are by far the highest in Delhi, followed by Beijing, and then the European cities.
Haiyan Ni, Ru-Jin Huang, Max M. Cosijn, Lu Yang, Jie Guo, Junji Cao, and Ulrike Dusek
Atmos. Chem. Phys., 20, 16041–16053, https://doi.org/10.5194/acp-20-16041-2020, https://doi.org/10.5194/acp-20-16041-2020, 2020
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We investigated sources of carbonaceous aerosols in Beijing and Xi'an during severe winter haze. Elemental carbon (EC) was dominated by vehicle emissions in Xi’an and coal burning in Beijing. Organic carbon (OC) increment during haze days was driven by the increase in primary and secondary OC (SOC). SOC was more from fossil sources in Beijing than Xi’an, especially during haze days. In Xi’an, no strong day–night differences in EC or OC sources suggest a large accumulation of particles.
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Short summary
Here we present the detailed molecular composition of the organic aerosol collected in three eastern Chinese cities from north to south, Changchun, Shanghai and Guangzhou, by applying LC–Orbitrap analysis. Accordingly, the aromaticity degree of chemical compounds decreases from north to south, while the oxidation degree increases from north to south, which can be explained by the different anthropogenic emissions and photochemical oxidation processes.
Here we present the detailed molecular composition of the organic aerosol collected in three...
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