Articles | Volume 14, issue 14
https://doi.org/10.5194/acp-14-7431-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-14-7431-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
18 Jul 2014
Research article |
| 18 Jul 2014
Black carbon concentrations and sources in the marine boundary layer of the tropical Atlantic Ocean using four methodologies
K. Pohl
Graduate School of Oceanography-University of Rhode Island, Narragansett, RI, USA
M. Cantwell
Environmental Protection Agency-Atlantic Ecology Division, Narragansett, RI, USA
P. Herckes
Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ, USA
R. Lohmann
Graduate School of Oceanography-University of Rhode Island, Narragansett, RI, USA
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Beatriz Sayuri Oyama, Maria de Fátima Andrade, Pierre Herckes, Ulrike Dusek, Thomas Röckmann, and Rupert Holzinger
Atmos. Chem. Phys., 16, 14397–14408, https://doi.org/10.5194/acp-16-14397-2016, https://doi.org/10.5194/acp-16-14397-2016, 2016
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Vehicular emissions have a strong impact on air pollution in big cities; hence, the study was performed in São Paulo city, where light- (LDVs) and heavy-duty vehicles (HDVs) run on different fuels. We find that organic aerosol emission from LDVs and HDVs is a complex process involving oxidation of fuel constituents, NOx chemistry, and condensation of unburned fuel hydrocarbons on new or existing particles. The obtained emission patterns can be used to study processing of young aerosol in Brazil.
Y. Mancilla, A. Mendoza, M. P. Fraser, and P. Herckes
Atmos. Chem. Phys., 16, 953–970, https://doi.org/10.5194/acp-16-953-2016, https://doi.org/10.5194/acp-16-953-2016, 2016
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Chemical characterization of fine aerosol was conducted due to air pollution by fine particles in the last decade. The diagnostic ratios and CMB receptor model based on organic markers showed that gasoline- and diesel-powered vehicles are the main emission sources (CMB = 64 %) of this class of organic compounds in PM2.5. Other pyrogenic sources as contributors to fine aerosols. Fine particles are related to human health impacts. In addition, these results can be useful for policy making.
J. Brito, L. V. Rizzo, P. Herckes, P. C. Vasconcellos, S. E. S. Caumo, A. Fornaro, R. Y. Ynoue, P. Artaxo, and M. F. Andrade
Atmos. Chem. Phys., 13, 12199–12213, https://doi.org/10.5194/acp-13-12199-2013, https://doi.org/10.5194/acp-13-12199-2013, 2013
B. Ervens, Y. Wang, J. Eagar, W. R. Leaitch, A. M. Macdonald, K. T. Valsaraj, and P. Herckes
Atmos. Chem. Phys., 13, 5117–5135, https://doi.org/10.5194/acp-13-5117-2013, https://doi.org/10.5194/acp-13-5117-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Unambiguous identification of N-containing oxygenated organic molecules using a chemical-ionization Orbitrap (CI-Orbitrap) in an eastern Chinese megacity
Estimating hub-height wind speed based on a machine learning algorithm: implications for wind energy assessment
Characteristics and degradation of organic aerosols from cooking sources based on hourly observations of organic molecular markers in urban environments
Characteristics of particulate-bound n-alkanes indicating sources of PM2.5 in Beijing, China
Characterization of volatile organic compounds and submicron organic aerosol in a traffic environment
Non-volatile marine and non-refractory continental sources of particle-phase amine during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES)
Effects of transport on a biomass burning plume from Indochina during EMeRGe-Asia identified by WRF-Chem
The shifting of secondary inorganic aerosol formation mechanisms during haze aggravation: the decisive role of aerosol liquid water
Collective geographical ecoregions and precursor sources driving Arctic new particle formation
Measurement report: Chemical components and 13C and 15N isotope ratios of fine aerosols over Tianjin, North China: year-round observations
Impact of biogenic secondary organic aerosol (SOA) loading on the molecular composition of wintertime PM2.5 in urban Tianjin: an insight from Fourier transform ion cyclotron resonance mass spectrometry
Impacts of biomass burning and photochemical processing on the light absorption of brown carbon in the southeastern Tibetan Plateau
Fates of secondary organic aerosols in the atmosphere identified from compound-specific dual-carbon isotope analysis of oxalic acid
Measurement report: Aerosol vertical profiles over the western North Atlantic Ocean during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES)
Characteristics of fine particle matter at the top of Shanghai Tower
Measurement report: Abundance and fractional solubilities of aerosol metals in urban Hong Kong – insights into factors that control aerosol metal dissolution in an urban site in South China
Measurement report: Intensive biomass burning emissions and rapid nitrate formation drive severe haze formation in the Sichuan Basin, China – insights from aerosol mass spectrometry
African smoke particles act as cloud condensation nuclei in the wintertime tropical North Atlantic boundary layer over Barbados
Measurement report: Changes in light absorption and molecular composition of water-soluble humic-like substances during a winter haze bloom-decay process in Guangzhou, China
Varying chiral ratio of pinic acid enantiomers above the Amazon rainforest
Impact of aging on the sources, volatility, and viscosity of organic aerosols in Chinese outflows
Biogenic and anthropogenic sources of isoprene and monoterpenes and their secondary organic aerosol in Delhi, India
Different physicochemical behaviors of nitrate and ammonium during transport: a case study on Mt. Hua, China
A method for using stationary networks to observe long-term trends of on-road emission factors of primary aerosol from heavy-duty vehicles
Atmospheric particle abundance and sea salt aerosol observations in the springtime Arctic: a focus on blowing snow and leads
Chromophores and chemical composition of brown carbon characterized at an urban kerbside by excitation–emission spectroscopy and mass spectrometry
Measurement report: Contrasting elevation-dependent light absorption by black and brown carbon: lessons from in situ measurements from the highly polluted Sichuan Basin to the pristine Tibetan Plateau
Long-term declines in atmospheric nitrogen and sulfur deposition reduce critical loads exceedances at multiple Canadian rural sites, 2000–2018
Composition and mixing state of Arctic aerosol and cloud residual particles from long-term single-particle observations at Zeppelin Observatory, Svalbard
A meteorological overview of the ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) campaign over the southeastern Atlantic during 2016–2018: Part 2 – Daily and synoptic characteristics
Insights into the single particle composition, size, mixing state and aspect ratio of freshly emitted mineral dust from field measurements in the Moroccan Sahara using electron microscopy
Measurement report: Characterization of sugars and amino acids in atmospheric fine particulates and their relationship to local primary sources
Seasonal variation of aerosol iron solubility in coarse and fine particles at an inland city in northwestern China
Organic enrichment in droplet residual particles relative to out of cloud over the northwestern Atlantic: analysis of airborne ACTIVATE data
Long-term trends and drivers of aerosol pH in eastern China
Potential underestimation of ambient brown carbon absorption based on the methanol extraction method and its impacts on source analysis
Contributions of primary sources to submicron organic aerosols in Delhi, India
Examination of brown carbon absorption from wildfires in the western US during the WE-CAN study
Source apportionment and evolution of N-containing aerosols at a rural cloud forest in Taiwan by isotope analysis
Measurement report: Characterisation and sources of the secondary organic carbon in a Chinese megacity over 5 years from 2016 to 2020
Exploring the inorganic composition of the Asian Tropopause Aerosol Layer using medium-duration balloon flights
Technical note: Use of PM2.5 to CO ratio as an indicator of wildfire smoke in urban areas
Ice-nucleating particles near two major dust source regions
The effect of COVID-19 restrictions on atmospheric new particle formation in Beijing
The effect of clouds and precipitation on the aerosol concentrations and composition in a boreal forest environment
High frequency of new particle formation events driven by summer monsoon in the central Tibetan Plateau, China
The impact of atmospheric motions on source-specific black carbon and the induced direct radiative effects over a river-valley region
Measurement report: The 10-year trend of PM2.5 major components and source tracers from 2008 to 2017 in an urban site of Hong Kong, China
Contribution of wood burning to exposures of PAHs and oxy-PAHs in Eastern Sweden
Chemical evolution of secondary organic aerosol tracers during high-PM2.5 episodes at a suburban site in Hong Kong over 4 months of continuous measurement
Yiqun Lu, Yingge Ma, Dan Dan Huang, Shengrong Lou, Sheng'ao Jing, Yaqin Gao, Hongli Wang, Yanjun Zhang, Hui Chen, Yunhua Chang, Naiqiang Yan, Jianmin Chen, Christian George, Matthieu Riva, and Cheng Huang
Atmos. Chem. Phys., 23, 3233–3245, https://doi.org/10.5194/acp-23-3233-2023, https://doi.org/10.5194/acp-23-3233-2023, 2023
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N-containing oxygenated organic molecules have been identified as important precursors of aerosol particles. We used an ultra-high-resolution mass spectrometer coupled with an online sample inlet to accurately measure their molecular composition, concentration level and variation patterns. We show their formation process and influencing factors in a Chinese megacity involving various volatile organic compound precursors and atmospheric oxidants, and we highlight the influence of PM2.5 episodes.
Boming Liu, Xin Ma, Jianping Guo, Hui Li, Shikuan Jin, Yingying Ma, and Wei Gong
Atmos. Chem. Phys., 23, 3181–3193, https://doi.org/10.5194/acp-23-3181-2023, https://doi.org/10.5194/acp-23-3181-2023, 2023
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Wind energy is one of the most essential clean and renewable forms of energy in today’s world. However, the traditional power law method generally estimates the hub-height wind speed by assuming a constant exponent between surface and hub-height wind speeds. This inevitably leads to significant uncertainties in estimating the wind speed profile. To minimize the uncertainties, we here use a machine learning algorithm known as random forest to estimate the wind speed at hub height.
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.
Jiyuan Yang, Guoyang Lei, Chang Liu, Yutong Wu, Kai Hu, Jinfeng Zhu, Junsong Bao, Weili Lin, and Jun Jin
Atmos. Chem. Phys., 23, 3015–3029, https://doi.org/10.5194/acp-23-3015-2023, https://doi.org/10.5194/acp-23-3015-2023, 2023
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The characteristics of n-alkanes and the contributions of various sources of PM2.5 in the atmosphere in Beijing were studied. There were marked seasonal and diurnal differences in the n-alkane concentrations (p<0.01). Particulate-bound n-alkanes were supplied by anthropogenic and biogenic sources; fossil fuel combustion was the dominant contributor. Vehicle exhausts strongly affect PM2.5 pollution. Controlling vehicle exhaust emissions is key to control n-alkane and PM2.5 pollution in Beijing.
Sanna Saarikoski, Heidi Hellén, Arnaud P. Praplan, Simon Schallhart, Petri Clusius, Jarkko V. Niemi, Anu Kousa, Toni Tykkä, Rostislav Kouznetsov, Minna Aurela, Laura Salo, Topi Rönkkö, Luis M. F. Barreira, Liisa Pirjola, and Hilkka Timonen
Atmos. Chem. Phys., 23, 2963–2982, https://doi.org/10.5194/acp-23-2963-2023, https://doi.org/10.5194/acp-23-2963-2023, 2023
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This study elucidates properties and sources of volatile organic compounds (VOCs) and organic aerosol (OA) in a traffic environment. Anthropogenic VOCs (aVOCs) were clearly higher than biogenic VOCs (bVOCs), but bVOCs produced a larger portion of oxidation products. OA consisted mostly of oxygenated OA, representing secondary OA (SOA). SOA was partly associated with bVOCs, but it was also related to long-range transport. Primary OA originated mostly from traffic.
Veronica Z. Berta, Lynn M. Russell, Derek J. Price, Chia-Li Chen, Alex K. Y. Lee, Patricia K. Quinn, Timothy S. Bates, Thomas G. Bell, and Michael J. Behrenfeld
Atmos. Chem. Phys., 23, 2765–2787, https://doi.org/10.5194/acp-23-2765-2023, https://doi.org/10.5194/acp-23-2765-2023, 2023
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Amines are compounds emitted from a variety of marine and continental sources and were measured by aerosol mass spectrometry and Fourier transform infrared spectroscopy during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) cruises. Secondary continental and primary marine sources of amines were identified by comparisons to tracers. The results show that the two methods are complementary for investigating amines in the marine environment.
Chuan-Yao Lin, Wan-Chin Chen, Yi-Yun Chien, Charles C. K. Chou, Chian-Yi Liu, Helmut Ziereis, Hans Schlager, Eric Förster, Florian Obersteiner, Ovid O. Krüger, Bruna A. Holanda, Mira L. Pöhlker, Katharina Kaiser, Johannes Schneider, Birger Bohn, Klaus Pfeilsticker, Benjamin Weyland, Maria Dolores Andrés Hernández, and John P. Burrows
Atmos. Chem. Phys., 23, 2627–2647, https://doi.org/10.5194/acp-23-2627-2023, https://doi.org/10.5194/acp-23-2627-2023, 2023
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During the EMeRGe campaign in Asia, atmospheric pollutants were measured on board the HALO aircraft. The WRF-Chem model was employed to evaluate the biomass burning (BB) plume transported from Indochina and its impact on the downstream areas. The combination of BB aerosol enhancement with cloud water resulted in a reduction in incoming shortwave radiation at the surface in southern China and the East China Sea, which potentially has significant regional climate implications.
Fei Xie, Yue Su, Yongli Tian, Yanju Shi, Xingjun Zhou, Peng Wang, Ruihong Yu, Wei Wang, Jiang He, Jinyuan Xin, and Changwei Lü
Atmos. Chem. Phys., 23, 2365–2378, https://doi.org/10.5194/acp-23-2365-2023, https://doi.org/10.5194/acp-23-2365-2023, 2023
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This work finds the shifting of secondary inorganic aerosol formation mechanisms during haze aggravation and explains the decisive role of aerosol liquid water on a broader scale (~ 500 μg m3) in an ammonia-rich atmosphere based on the in situ high-resolution online monitoring datasets.
James Brean, David C. S. Beddows, Roy M. Harrison, Congbo Song, Peter Tunved, Johan Ström, Radovan Krejci, Eyal Freud, Andreas Massling, Henrik Skov, Eija Asmi, Angelo Lupi, and Manuel Dall'Osto
Atmos. Chem. Phys., 23, 2183–2198, https://doi.org/10.5194/acp-23-2183-2023, https://doi.org/10.5194/acp-23-2183-2023, 2023
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Our results emphasize how understanding the geographical variation in surface types across the Arctic is key to understanding secondary aerosol sources. We provide a harmonised analysis of new particle formation across the Arctic.
Zhichao Dong, Chandra Mouli Pavuluri, Zhanjie Xu, Yu Wang, Peisen Li, Pingqing Fu, and Cong-Qiang Liu
Atmos. Chem. Phys., 23, 2119–2143, https://doi.org/10.5194/acp-23-2119-2023, https://doi.org/10.5194/acp-23-2119-2023, 2023
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This study has provided comprehensive baseline data of carbonaceous and inorganic aerosols as well as their isotope ratios in the Tianjin region, North China, found that Tianjin aerosols were derived from coal combustion, biomass burning and photochemical reactions of VOCs, and also implied that the Tianjin aerosols were more aged during long-range atmospheric transport in summer via carbonaceous and isotope data analysis.
Shujun Zhong, Shuang Chen, Junjun Deng, Yanbing Fan, Qiang Zhang, Qiaorong Xie, Yulin Qi, Wei Hu, Libin Wu, Xiaodong Li, Chandra Mouli Pavuluri, Jialei Zhu, Xin Wang, Di Liu, Xiaole Pan, Yele Sun, Zifa Wang, Yisheng Xu, Haijie Tong, Hang Su, Yafang Cheng, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 23, 2061–2077, https://doi.org/10.5194/acp-23-2061-2023, https://doi.org/10.5194/acp-23-2061-2023, 2023
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This study investigated the role of the secondary organic aerosol (SOA) loading on the molecular composition of wintertime urban aerosols by ultrahigh-resolution mass spectrometry. Results demonstrate that the SOA loading is an important factor associated with the oxidation degree, nitrate group content, and chemodiversity of nitrooxy–organosulfates. Our study also found that the hydrolysis of nitrooxy–organosulfates is a possible pathway for the formation of organosulfates.
Jie Tian, Qiyuan Wang, Yongyong Ma, Jin Wang, Yongming Han, and Junji Cao
Atmos. Chem. Phys., 23, 1879–1892, https://doi.org/10.5194/acp-23-1879-2023, https://doi.org/10.5194/acp-23-1879-2023, 2023
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We investigated the light absorption properties of brown carbon (BrC) in the Tibetan Plateau (TP). BrC made a substantial contribution to the submicron aerosol absorption, which is related to the cross-border transport of biomass burning emission and secondary aerosol from Southeast Asia. The radiative effect of BrC was half that of black carbon, which can remarkably affect the radiative balance of the TP.
Buqing Xu, Jiao Tang, Tiangang Tang, Shizhen Zhao, Guangcai Zhong, Sanyuan Zhu, Jun Li, and Gan Zhang
Atmos. Chem. Phys., 23, 1565–1578, https://doi.org/10.5194/acp-23-1565-2023, https://doi.org/10.5194/acp-23-1565-2023, 2023
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We analyzed compound-specific dual-carbon isotope signatures (Δ14C and δ13C) of dominant secondary organic aerosol (SOA) tracer molecules (i.e., oxalic acid) to investigate the fates of SOAs in the atmosphere at five emission hotspots in China. The results indicated that SOA carbon sources and chemical processes producing SOAs vary spatially and seasonally, and these variations need to be included in Chinese climate projection models and air quality management practices.
Francesca Gallo, Kevin J. Sanchez, Bruce E. Anderson, Ryan Bennett, Matthew D. Brown, Ewan C. Crosbie, Chris Hostetler, Carolyn Jordan, Melissa Yang Martin, Claire E. Robinson, Lynn M. Russell, Taylor J. Shingler, Michael A. Shook, Kenneth L. Thornhill, Elizabeth B. Wiggins, Edward L. Winstead, Armin Wisthaler, Luke D. Ziemba, and Richard H. Moore
Atmos. Chem. Phys., 23, 1465–1490, https://doi.org/10.5194/acp-23-1465-2023, https://doi.org/10.5194/acp-23-1465-2023, 2023
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We integrate in situ ship- and aircraft-based measurements of aerosol, trace gases, and meteorological parameters collected during the NASA North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) field campaigns in the western North Atlantic Ocean region. A comprehensive characterization of the vertical profiles of aerosol properties under different seasonal regimes is provided for improving the understanding of aerosol key processes and aerosol–cloud interactions in marine regions.
Changqin Yin, Jianming Xu, Wei Gao, Liang Pan, Yixuan Gu, Qingyan Fu, and Fan Yang
Atmos. Chem. Phys., 23, 1329–1343, https://doi.org/10.5194/acp-23-1329-2023, https://doi.org/10.5194/acp-23-1329-2023, 2023
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The particle matter (PM2.5) at the top of the 632 m high Shanghai Tower was found to be higher than the surface from June to October due to unexpected larger PM2.5 levels during early to middle afternoon at Shanghai Tower. We suppose the significant chemical production of secondary species existed in the mid-upper planetary boundary layer. We found a high nitrate concentration at the tower site for both daytime and nighttime in winter, implying efficient gas-phase and heterogeneous formation.
Junwei Yang, Lan Ma, Xiao He, Wing Chi Au, Yanhao Miao, Wen-Xiong Wang, and Theodora Nah
Atmos. Chem. Phys., 23, 1403–1419, https://doi.org/10.5194/acp-23-1403-2023, https://doi.org/10.5194/acp-23-1403-2023, 2023
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Water-soluble metals play key roles in human health and atmospheric processes. We report the seasonal abundance and fractional solubilities of different metals in aerosols collected in urban Hong Kong as well as the key factors that modulated solubilities of the various metals in fine aerosols. Our results highlight the dual roles (i.e., acidifying the aerosol particle and providing a liquid reaction medium) that sulfate plays in the acid dissolution of metals in fine aerosols in Hong Kong.
Zhier Bao, Xinyi Zhang, Qing Li, Jiawei Zhou, Guangming Shi, Li Zhou, Fumo Yang, Shaodong Xie, Dan Zhang, Chongzhi Zhai, Zhenliang Li, Chao Peng, and Yang Chen
Atmos. Chem. Phys., 23, 1147–1167, https://doi.org/10.5194/acp-23-1147-2023, https://doi.org/10.5194/acp-23-1147-2023, 2023
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We characterised non-refractory fine particulate matter (PM2.5) during winter in the Sichuan Basin (SCB), Southwest China. The factors driving severe aerosol pollution were revealed, highlighting the importance of rapid nitrate formation and intensive biomass burning. Nitrate was primarily formed through gas-phase oxidation during daytime and aqueous-phase oxidation during nighttime. Controlling nitrate and biomass burning will benefit the mitigation of haze formation in the SCB.
Haley M. Royer, Mira L. Pöhlker, Ovid Krüger, Edmund Blades, Peter Sealy, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Andrew P. Ault, Patricia K. Quinn, Paquita Zuidema, Christopher Pöhlker, Ulrich Pöschl, Meinrat Andreae, and Cassandra J. Gaston
Atmos. Chem. Phys., 23, 981–998, https://doi.org/10.5194/acp-23-981-2023, https://doi.org/10.5194/acp-23-981-2023, 2023
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This paper presents atmospheric particle chemical composition and measurements of aerosol water uptake properties collected at Ragged Point, Barbados, during the winter of 2020. The result of this study indicates the importance of small African smoke particles for cloud droplet formation in the tropical North Atlantic and highlights the large spatial and temporal pervasiveness of smoke over the Atlantic Ocean.
Chunlin Zou, Tao Cao, Meiju Li, Jianzhong Song, Bin Jiang, Wanglu Jia, Jun Li, Xiang Ding, Zhiqiang Yu, Gan Zhang, and Ping'an Peng
Atmos. Chem. Phys., 23, 963–979, https://doi.org/10.5194/acp-23-963-2023, https://doi.org/10.5194/acp-23-963-2023, 2023
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In this study, PM2.5 samples were obtained during a winter haze event in Guangzhou, China, and light absorption and molecular composition of humic-like substances (HULIS) were investigated by UV–Vis spectrophotometry and ultrahigh-resolution mass spectrometry. The findings obtained present some differences from the results reported in other regions of China and significantly enhanced our understanding of HULIS evolution during haze bloom-decay processes in the subtropic region of southern China.
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.
Tingting Feng, Yingkun Wang, Weiwei Hu, Ming Zhu, Wei Song, Wei Chen, Yanyan Sang, Zheng Fang, Wei Deng, Hua Fang, Xu Yu, Cheng Wu, Bin Yuan, Shan Huang, Min Shao, Xiaofeng Huang, Lingyan He, Young Ro Lee, Lewis Gregory Huey, Francesco Canonaco, Andre S. H. Prevot, and Xinming Wang
Atmos. Chem. Phys., 23, 611–636, https://doi.org/10.5194/acp-23-611-2023, https://doi.org/10.5194/acp-23-611-2023, 2023
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To investigate the impact of aging processes on organic aerosols (OA), we conducted a comprehensive field study at a continental remote site using an on-line mass spectrometer. The results show that OA in the Chinese outflows were strongly influenced by upwind anthropogenic emissions. The aging processes can significantly decrease the OA volatility and result in a varied viscosity of OA under different circumstances, signifying the complex physiochemical properties of OA in aged plumes.
Daniel J. Bryant, Beth S. Nelson, Stefan J. Swift, Sri Hapsari Budisulistiorini, Will S. Drysdale, Adam R. Vaughan, Mike J. Newland, James R. Hopkins, James M. Cash, Ben Langford, Eiko Nemitz, W. Joe F. Acton, C. Nicholas Hewitt, Tuhin Mandal, Bhola R. Gurjar, Shivani, Ranu Gadi, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 23, 61–83, https://doi.org/10.5194/acp-23-61-2023, https://doi.org/10.5194/acp-23-61-2023, 2023
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This paper investigates the sources of isoprene and monoterpene compounds and their particulate-phase oxidation products in Delhi, India. This was done to improve our understanding of the sources, concentrations, and fate of volatile emissions in megacities. By studying the chemical composition of offline filter samples, we report that a significant share of the oxidised organic aerosol in Delhi is from isoprene and monoterpenes. This has implications for human health and policy development.
Can Wu, Cong Cao, Jianjun Li, Shaojun Lv, Jin Li, Xiaodi Liu, Si Zhang, Shijie Liu, Fan Zhang, Jingjing Meng, and Gehui Wang
Atmos. Chem. Phys., 22, 15621–15635, https://doi.org/10.5194/acp-22-15621-2022, https://doi.org/10.5194/acp-22-15621-2022, 2022
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Over the past decade, the relative abundance of NH4NO3 in aerosol has been enhanced in most urban areas of China, which profoundly affects the PM2.5 pollution episodes. Our work finds that fine-particle nitrate and ammonium exhibited distinct, different physicochemical behaviors in the aerosol aging process.
Helen L. Fitzmaurice and Ronald C. Cohen
Atmos. Chem. Phys., 22, 15403–15411, https://doi.org/10.5194/acp-22-15403-2022, https://doi.org/10.5194/acp-22-15403-2022, 2022
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We develop a novel method for finding heavy-duty vehicle (HDV) emission factors (g PM kg fuel) using regulatory sensor networks and publicly available traffic data. We find that particulate matter emission factors have decreased by a factor of ~ 9 in the past decade in the San Francisco Bay area. Because of the wide availability of similar data sets across the USA and globally, this method could be applied to other settings to understand long-term trends and regional differences in HDV emissions.
Qianjie Chen, Jessica A. Mirrielees, Sham Thanekar, Nicole A. Loeb, Rachel M. Kirpes, Lucia M. Upchurch, Anna J. Barget, Nurun Nahar Lata, Angela R. W. Raso, Stephen M. McNamara, Swarup China, Patricia K. Quinn, Andrew P. Ault, Aaron Kennedy, Paul B. Shepson, Jose D. Fuentes, and Kerri A. Pratt
Atmos. Chem. Phys., 22, 15263–15285, https://doi.org/10.5194/acp-22-15263-2022, https://doi.org/10.5194/acp-22-15263-2022, 2022
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During a spring field campaign in the coastal Arctic, ultrafine particles were enhanced during high wind speeds, and coarse-mode particles were reduced during blowing snow. Calculated periods blowing snow were overpredicted compared to observations. Sea spray aerosols produced by sea ice leads affected the composition of aerosols and snowpack. An improved understanding of aerosol emissions from leads and blowing snow is critical for predicting the future climate of the rapidly warming Arctic.
Feng Jiang, Junwei Song, Jonas Bauer, Linyu Gao, Magdalena Vallon, Reiner Gebhardt, Thomas Leisner, Stefan Norra, and Harald Saathoff
Atmos. Chem. Phys., 22, 14971–14986, https://doi.org/10.5194/acp-22-14971-2022, https://doi.org/10.5194/acp-22-14971-2022, 2022
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We studied brown carbon aerosol during typical summer and winter periods in downtown Karlsruhe in southwestern Germany. The chromophore and chemical composition of brown carbon was determined by excitation–emission spectroscopy and mass spectrometry. The chromophore types and sources were substantially different in winter and summer. Humic-like chromophores of different degrees of oxidation dominated and were associated with molecules of different molecular weight and nitrogen content.
Suping Zhao, Shaofeng Qi, Ye Yu, Shichang Kang, Longxiang Dong, Jinbei Chen, and Daiying Yin
Atmos. Chem. Phys., 22, 14693–14708, https://doi.org/10.5194/acp-22-14693-2022, https://doi.org/10.5194/acp-22-14693-2022, 2022
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Light absorption by aerosols is poorly understood at the eastern slope of the Tibetan Plateau (TP). We conducted the first in situ PM1 chemical measurements from the polluted Sichuan Basin to the eastern TP. A contrasting changes in mass absorption efficiency of black and brown carbon with altitude is found due to source differences. This study contributes to the understanding of the difference in light absorption by carbon with altitude, from the polluted basins to the pristine TP.
Irene Cheng, Leiming Zhang, Zhuanshi He, Hazel Cathcart, Daniel Houle, Amanda Cole, Jian Feng, Jason O'Brien, Anne Marie Macdonald, Julian Aherne, and Jeffrey Brook
Atmos. Chem. Phys., 22, 14631–14656, https://doi.org/10.5194/acp-22-14631-2022, https://doi.org/10.5194/acp-22-14631-2022, 2022
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Nitrogen (N) and sulfur (S) deposition decreased significantly at 14 Canadian sites during 2000–2018. The greatest decline was observed in southeastern Canada owing to regional SO2 and NOx reductions. Wet deposition was more important than dry deposition, comprising 71–95 % of total N and 45–89 % of total S deposition. While critical loads (CLs) were exceeded at a few sites in the early 2000s, acidic deposition declined below CLs after 2012, which signifies recovery from legacy acidification.
Kouji Adachi, Yutaka Tobo, Makoto Koike, Gabriel Freitas, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 22, 14421–14439, https://doi.org/10.5194/acp-22-14421-2022, https://doi.org/10.5194/acp-22-14421-2022, 2022
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Ambient aerosol and cloud residual particles in the fine mode were collected at Zeppelin Observatory in Svalbard and were analyzed using transmission electron microscopy. Fractions of mineral dust and sea salt particles increased in cloud residual samples collected at ambient temperatures below 0 °C. This study highlights the variety of aerosol and cloud residual particle compositions and mixing states that influence or are influenced by aerosol–cloud interactions in Arctic low-level clouds.
Ju-Mee Ryoo, Leonhard Pfister, Rei Ueyama, Paquita Zuidema, Robert Wood, Ian Chang, and Jens Redemann
Atmos. Chem. Phys., 22, 14209–14241, https://doi.org/10.5194/acp-22-14209-2022, https://doi.org/10.5194/acp-22-14209-2022, 2022
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The variability in the meteorological fields during each deployment is highly modulated at a daily to synoptic timescale. This paper, along with part 1, the climatological overview paper, provides a meteorological context for interpreting the airborne measurements gathered during the three ORACLES deployments. This study supports related studies focusing on the detailed investigation of the processes controlling stratocumulus decks, aerosol lifting, transport, and their interactions.
Agnesh Panta, Konrad Kandler, Andres Alastuey, Cristina González-Flórez, Adolfo González-Romero, Martina Klose, Xavier Querol, Cristina Reche, Jesús Yus-Díez, and Carlos Pérez García-Pando
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-742, https://doi.org/10.5194/acp-2022-742, 2022
Revised manuscript accepted for ACP
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Desert dust is a major aerosol component of the Earth's system and affects climate. Dust properties are influenced by particle size, mineralogy, shape, and mixing state. This work characterizes freshly emitted individual mineral dust particles from a major source region using electron microscopy. Our new insights on the critical particle-specific information will contribute to better constraining climate models that consider mineralogical variations in their representation of the dust cycle.
Ren-Guo Zhu, Hua-Yun Xiao, Liqin Cheng, Huixiao Zhu, Hongwei Xiao, and Yunyun Gong
Atmos. Chem. Phys., 22, 14019–14036, https://doi.org/10.5194/acp-22-14019-2022, https://doi.org/10.5194/acp-22-14019-2022, 2022
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Sugars and amino acids are major classes of organic components in atmospheric fine particles and play important roles in the atmosphere. To identify their sources in different regions, the concentrations and compositions of sugar amino acids in fine particles were analysed. Our findings suggest that combining specific sugar tracers and chemical profiles of combined amino acids in local emission sources can identify various source characteristics of primary sources.
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. Discuss., https://doi.org/10.5194/acp-2022-725, https://doi.org/10.5194/acp-2022-725, 2022
Revised manuscript accepted for ACP
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This work investigated seasonal variation of aerosol Fe solubility for coarse and fine particles in Xi’an, a megacity severely in northwestern China 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.
Hossein Dadashazar, Andrea F. Corral, Ewan Crosbie, Sanja Dmitrovic, Simon Kirschler, Kayla McCauley, Richard Moore, Claire Robinson, Joseph S. Schlosser, Michael Shook, K. Lee Thornhill, Christiane Voigt, Edward Winstead, Luke Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 22, 13897–13913, https://doi.org/10.5194/acp-22-13897-2022, https://doi.org/10.5194/acp-22-13897-2022, 2022
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Multi-season airborne data over the northwestern Atlantic show that organic mass fraction and the relative amount of oxygenated organics within that fraction are enhanced in droplet residual particles as compared to particles below and above cloud. In-cloud aqueous processing is shown to be a potential driver of this compositional shift in cloud. This implies that aerosol–cloud interactions in the region reduce aerosol hygroscopicity due to the jump in the organic : sulfate ratio in cloud.
Min Zhou, Guangjie Zheng, Hongli Wang, Liping Qiao, Shuhui Zhu, DanDan Huang, Jingyu An, Shengrong Lou, Shikang Tao, Qian Wang, Rusha Yan, Yingge Ma, Changhong Chen, Yafang Cheng, Hang Su, and Cheng Huang
Atmos. Chem. Phys., 22, 13833–13844, https://doi.org/10.5194/acp-22-13833-2022, https://doi.org/10.5194/acp-22-13833-2022, 2022
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The trend of aerosol pH and its drivers is crucial in understanding the multiphase formation pathways of aerosols. We reported the first trend analysis of aerosol pH from 2011 to 2019 in eastern China. Although significant variations of aerosol compositions were observed from 2011 to 2019, the aerosol pH estimated by model only slightly declined by 0.24. Our work shows that the opposite effects of SO42− and non-volatile cation changes play key roles in determining the moderate pH trend.
Zhenqi Xu, Wei Feng, Yicheng Wang, Haoran Ye, Yuhang Wang, Hong Liao, and Mingjie Xie
Atmos. Chem. Phys., 22, 13739–13752, https://doi.org/10.5194/acp-22-13739-2022, https://doi.org/10.5194/acp-22-13739-2022, 2022
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This work uses a solvent (DMF) that can efficiently dissolve low-volatility OC to examine BrC absorption and sources, which will benefit future investigations on the physicochemical properties of large organic molecules. The study results also shed light on potential sources for methanol-insoluble OC. These results highlight the importance of testing different solvents to investigate the structures and light absorption of low-volatility BrC.
Sahil Bhandari, Zainab Arub, Gazala Habib, Joshua S. Apte, and Lea Hildebrandt Ruiz
Atmos. Chem. Phys., 22, 13631–13657, https://doi.org/10.5194/acp-22-13631-2022, https://doi.org/10.5194/acp-22-13631-2022, 2022
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Here we determine the sources of primary organic aerosol in Delhi, India, in two different seasons. In winter, the main sources are traffic and biomass burning; in the summer, the main sources are traffic and cooking. We obtain this result by conducting source apportionment resolved by time of day, using data from an aerosol chemical speciation monitor. Results from this work can be used to better design policies that target sources of organic aerosol.
Amy P. Sullivan, Rudra P. Pokhrel, Yingjie Shen, Shane M. Murphy, Darin W. Toohey, Teresa Campos, Jakob Lindaas, Emily V. Fischer, and Jeffrey L. Collett Jr.
Atmos. Chem. Phys., 22, 13389–13406, https://doi.org/10.5194/acp-22-13389-2022, https://doi.org/10.5194/acp-22-13389-2022, 2022
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During the WE-CAN (Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption and Nitrogen) study, brown carbon (BrC) absorption was measured on the NSF/NCAR C-130 aircraft using a particle-into-liquid sampler and photoacoustic aerosol absorption spectrometer. Approximately 45 % of the BrC absorption in wildfires was observed to be due to water-soluble species. The ratio of BrC absorption to WSOC or ΔCO showed no clear dependence on fire dynamics or the time since emission over 9 h.
Ting-Yu Chen, Chia-Li Chen, Yi-Chi Chen, Charles C.-K. Chou, Haojia Ren, and Hui-Ming Hung
Atmos. Chem. Phys., 22, 13001–13012, https://doi.org/10.5194/acp-22-13001-2022, https://doi.org/10.5194/acp-22-13001-2022, 2022
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The anthropogenic influence on aerosol composition in a downstream river-valley forest was investigated using FTIR and isotope analysis. A higher N-containing species concentration during daytime fog events indicates that a stronger inversion leads to higher pollutant concentrations, and the fog enhances the aqueous-phase chemical processes. Moreover, the observed size-dependent oxygen isotope suggests the contribution of organic peroxyl radicals to local nitrate formation for small particles.
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.
Hazel Vernier, Neeraj Rastogi, Hongyu Liu, Amit Kumar Pandit, Kris Bedka, Anil Patel, Madineni Venkat Ratnam, Buduru Suneel Kumar, Bo Zhang, Harish Gadhavi, Frank Wienhold, Gwenael Berthet, and Jean-Paul Vernier
Atmos. Chem. Phys., 22, 12675–12694, https://doi.org/10.5194/acp-22-12675-2022, https://doi.org/10.5194/acp-22-12675-2022, 2022
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The chemical composition of the stratospheric aerosols collected aboard high-altitude balloons above the summer Asian monsoon reveals the presence of nitrate/nitrite. Using numerical simulations and satellite observations, we found that pollution as well as lightning could explain some of our observations.
Daniel A. Jaffe, Brendan Schnieder, and Daniel Inouye
Atmos. Chem. Phys., 22, 12695–12704, https://doi.org/10.5194/acp-22-12695-2022, https://doi.org/10.5194/acp-22-12695-2022, 2022
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In this paper we use commonly measured pollutants (PM2.5 and carbon monoxide) to develop a Monte Carlo simulation of the mixing of urban pollution with smoke. The simulations compare well with observations from a heavily impacted smoke site and show that we can use standard regulatory measurements to quantify the amount of smoke in urban areas.
Charlotte M. Beall, Thomas C. J. Hill, Paul J. DeMott, Tobias Köneman, Michael Pikridas, Frank Drewnick, Hartwig Harder, Christopher Pöhlker, Jos Lelieveld, Bettina Weber, Minas Iakovides, Roman Prokeš, Jean Sciare, Meinrat O. Andreae, M. Dale Stokes, and Kimberly A. Prather
Atmos. Chem. Phys., 22, 12607–12627, https://doi.org/10.5194/acp-22-12607-2022, https://doi.org/10.5194/acp-22-12607-2022, 2022
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Ice-nucleating particles (INPs) are rare aerosols that can trigger ice formation in clouds and affect climate-relevant cloud properties such as phase, reflectivity and lifetime. Dust is the dominant INP source, yet few measurements have been reported near major dust sources. We report INP observations within hundreds of kilometers of the biggest dust source regions globally: the Sahara and the Arabian Peninsula. Results show that at temperatures > −15 °C, INPs are dominated by organics.
Chao Yan, Yicheng Shen, Dominik Stolzenburg, Lubna Dada, Ximeng Qi, Simo Hakala, Anu-Maija Sundström, Yishuo Guo, Antti Lipponen, Tom V. Kokkonen, Jenni Kontkanen, Runlong Cai, Jing Cai, Tommy Chan, Liangduo Chen, Biwu Chu, Chenjuan Deng, Wei Du, Xiaolong Fan, Xu-Cheng He, Juha Kangasluoma, Joni Kujansuu, Mona Kurppa, Chang Li, Yiran Li, Zhuohui Lin, Yiliang Liu, Yuliang Liu, Yiqun Lu, Wei Nie, Jouni Pulliainen, Xiaohui Qiao, Yonghong Wang, Yifan Wen, Ye Wu, Gan Yang, Lei Yao, Rujing Yin, Gen Zhang, Shaojun Zhang, Feixue Zheng, Ying Zhou, Antti Arola, Johanna Tamminen, Pauli Paasonen, Yele Sun, Lin Wang, Neil M. Donahue, Yongchun Liu, Federico Bianchi, Kaspar R. Daellenbach, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Aijun Ding, Jingkun Jiang, and Markku Kulmala
Atmos. Chem. Phys., 22, 12207–12220, https://doi.org/10.5194/acp-22-12207-2022, https://doi.org/10.5194/acp-22-12207-2022, 2022
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Atmospheric new particle formation (NPF) is a dominant source of atmospheric ultrafine particles. In urban environments, traffic emissions are a major source of primary pollutants, but their contribution to NPF remains under debate. During the COVID-19 lockdown, traffic emissions were significantly reduced, providing a unique chance to examine their relevance to NPF. Based on our comprehensive measurements, we demonstrate that traffic emissions alone are not able to explain the NPF in Beijing.
Sini Isokääntä, Paul Kim, Santtu Mikkonen, Thomas Kühn, Harri Kokkola, Taina Yli-Juuti, Liine Heikkinen, Krista Luoma, Tuukka Petäjä, Zak Kipling, Daniel Partridge, and Annele Virtanen
Atmos. Chem. Phys., 22, 11823–11843, https://doi.org/10.5194/acp-22-11823-2022, https://doi.org/10.5194/acp-22-11823-2022, 2022
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This research employs air mass history analysis and observations to study how clouds and precipitation affect atmospheric aerosols during transport to a boreal forest site. The mass concentrations of studied chemical species showed exponential decrease as a function of accumulated rain along the air mass route. Our analysis revealed in-cloud sulfate formation, while no major changes in organic mass were seen. Most of the in-cloud-formed sulfate could be assigned to particle sizes above 200 nm.
Lizi Tang, Min Hu, Dongjie Shang, Xin Fang, Janjiong Mao, Wanyun Xu, Jiacheng Zhou, Weixiong Zhao, Yaru Wang, Chong Zhang, Yingjie Zhang, Jianlin Hu, Limin Zeng, Chunxiang Ye, Song Guo, and Zhijun Wu
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-440, https://doi.org/10.5194/acp-2022-440, 2022
Preprint under review for ACP
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There was an evident distinction in the frequencies of NPF events at Nam Co station in the Tibetan Plateau with 15 % in pre-monsoon season and 80 % in monsoon season. The frequent NPF events in monsoon season resulted from the higher concentration of organic vapours, which was brought from northeast India by the strong southerly monsoon. It had increased significantly the amount of aerosol and CCN compared with those in pre-monsoon season, which may markedly affect the earth's radiation balance.
Huikun Liu, Qiyuan Wang, Suixin Liu, Bianhong Zhou, Yao Qu, Jie Tian, Ting Zhang, Yongming Han, and Junji Cao
Atmos. Chem. Phys., 22, 11739–11757, https://doi.org/10.5194/acp-22-11739-2022, https://doi.org/10.5194/acp-22-11739-2022, 2022
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Atmospheric motions play an important role in the mass concentration and the direct radiative effect (DRE) of black carbon (BC). The finding from this study elaborated the impacts of different scales of atmospheric motion on source-specific BC and its DREs, which revealed the nonlinear change between BC mass concentration and its DREs and emphasizes the importance of regionally transported BC for potential climatic effects.
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.
Hwanmi Lim, Sanna Silvergren, Silvia Spinicci, Farshid Mashayekhy Rad, Ulrika Nilsson, Roger Westerholm, and Christer Johansson
Atmos. Chem. Phys., 22, 11359–11379, https://doi.org/10.5194/acp-22-11359-2022, https://doi.org/10.5194/acp-22-11359-2022, 2022
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Air pollutants from wood burning become more important as other regulated emissions are being reduced, e.g. combustion of diesel. We analysed particles in residential areas and found that local wood burning was the most important source of polycyclic aromatic hydrocarbons (PAHs). Specific tracers were used to separate wood combustion from other contributions. Calculations of population exposure showed that the mix of PAHs may cause 13 cancer cases per 0.1 million inhabitants.
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.
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