Articles | Volume 21, issue 24
https://doi.org/10.5194/acp-21-18271-2021
© 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-21-18271-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
16 Dec 2021
Research article |
| 16 Dec 2021
| 16 Dec 2021
Urban aerosol chemistry at a land–water transition site during summer – Part 2: Aerosol pH and liquid water content
Michael A. Battaglia Jr.
Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD, USA
current affiliation: School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA
Nicholas Balasus
Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD, USA
Katherine Ball
Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD, USA
Vanessa Caicedo
Joint Center for Earth Systems Technology, University of Maryland, Baltimore County, Baltimore, MD, USA
Ruben Delgado
Joint Center for Earth Systems Technology, University of Maryland, Baltimore County, Baltimore, MD, USA
Annmarie G. Carlton
Department of Chemistry, University of California, Irvine, CA, USA
Christopher J. Hennigan
CORRESPONDING AUTHOR
Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD, USA
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Measurements of aerosol and gas composition were carried out at a land–water transition site near Baltimore, MD. Gas-phase ammonia concentrations were highly elevated compared to measurements at a nearby inland site. Our analysis reveals that NH2 was from both industrial and agricultural sources. This had a pronounced effect on aerosol chemical composition at the site, most notably contributing to episodic spikes of aerosol nitrate.
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Claudia Bernier, Yuxuan Wang, Guillaume Gronoff, Timothy Berkoff, K. Emma Knowland, John T. Sullivan, Ruben Delgado, Vanessa Caicedo, and Brian Carroll
Atmos. Chem. Phys., 22, 15313–15331, https://doi.org/10.5194/acp-22-15313-2022, https://doi.org/10.5194/acp-22-15313-2022, 2022
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Jianfeng Li, Yuhang Wang, Ruixiong Zhang, Charles Smeltzer, Andrew Weinheimer, Jay Herman, K. Folkert Boersma, Edward A. Celarier, Russell W. Long, James J. Szykman, Ruben Delgado, Anne M. Thompson, Travis N. Knepp, Lok N. Lamsal, Scott J. Janz, Matthew G. Kowalewski, Xiong Liu, and Caroline R. Nowlan
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Haihan Chen, Anna L. Hodshire, John Ortega, James Greenberg, Peter H. McMurry, Annmarie G. Carlton, Jeffrey R. Pierce, Dave R. Hanson, and James N. Smith
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Atmos. Chem. Phys., 17, 11107–11133, https://doi.org/10.5194/acp-17-11107-2017, https://doi.org/10.5194/acp-17-11107-2017, 2017
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Atmos. Meas. Tech., 10, 1707–1721, https://doi.org/10.5194/amt-10-1707-2017, https://doi.org/10.5194/amt-10-1707-2017, 2017
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Vanessa Caicedo, Bernhard Rappenglück, Barry Lefer, Gary Morris, Daniel Toledo, and Ruben Delgado
Atmos. Meas. Tech., 10, 1609–1622, https://doi.org/10.5194/amt-10-1609-2017, https://doi.org/10.5194/amt-10-1609-2017, 2017
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Three methods for estimating the boundary layer height using aerosol backscatter measurements are evaluated here. Radiosonde profiles are used to evaluate aerosol-backscatter-derived boundary layer heights. Overall good agreement between radiosonde and all aerosol-derived boundary layer heights was found, and specific limitations to each method are discussed. A recommended method is given for future aerosol backscatter retrieval of the boundary layer height.
Kathleen M. Fahey, Annmarie G. Carlton, Havala O. T. Pye, Jaemeen Baek, William T. Hutzell, Charles O. Stanier, Kirk R. Baker, K. Wyat Appel, Mohammed Jaoui, and John H. Offenberg
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Chemical transport models (CTMs) are a crucial tool in understanding links between emissions, air quality, and climate. Only a simple description of cloud chemistry has been implemented in many of these; however, clouds play a major role in the physicochemical processing of atmospheric species. In CMAQ, EPA’s widely used CTM, the cloud code is limited to the treatment of simple chemistry. We update CMAQ clouds to consider additional chemistry and then examine regional impacts of these updates.
Mithu Debnath, Giacomo Valerio Iungo, W. Alan Brewer, Aditya Choukulkar, Ruben Delgado, Scott Gunter, Julie K. Lundquist, John L. Schroeder, James M. Wilczak, and Daniel Wolfe
Atmos. Meas. Tech., 10, 1215–1227, https://doi.org/10.5194/amt-10-1215-2017, https://doi.org/10.5194/amt-10-1215-2017, 2017
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The XPIA experiment was conducted in 2015 at the Boulder Atmospheric Observatory to estimate capabilities of various remote-sensing techniques for the characterization of complex atmospheric flows. Among different tests, XPIA provided the unique opportunity to perform simultaneous virtual towers with Ka-band radars and scanning Doppler wind lidars. Wind speed and wind direction were assessed against lidar profilers and sonic anemometer data, highlighting a good accuracy of the data retrieved.
Mithu Debnath, G. Valerio Iungo, Ryan Ashton, W. Alan Brewer, Aditya Choukulkar, Ruben Delgado, Julie K. Lundquist, William J. Shaw, James M. Wilczak, and Daniel Wolfe
Atmos. Meas. Tech., 10, 431–444, https://doi.org/10.5194/amt-10-431-2017, https://doi.org/10.5194/amt-10-431-2017, 2017
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Triple RHI scans were performed with three simultaneous scanning Doppler wind lidars and assessed with lidar profiler and sonic anemometer data. This test is part of the XPIA experiment. The scan strategy consists in two lidars performing co-planar RHI scans, while a third lidar measures the transversal velocity component. The results show that horizontal velocity and wind direction are measured with good accuracy, while the vertical velocity is typically measured with a significant error.
Havala O. T. Pye, Benjamin N. Murphy, Lu Xu, Nga L. Ng, Annmarie G. Carlton, Hongyu Guo, Rodney Weber, Petros Vasilakos, K. Wyat Appel, Sri Hapsari Budisulistiorini, Jason D. Surratt, Athanasios Nenes, Weiwei Hu, Jose L. Jimenez, Gabriel Isaacman-VanWertz, Pawel K. Misztal, and Allen H. Goldstein
Atmos. Chem. Phys., 17, 343–369, https://doi.org/10.5194/acp-17-343-2017, https://doi.org/10.5194/acp-17-343-2017, 2017
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We use a chemical transport model to examine how organic compounds in the atmosphere interact with water present in particles. Organic compounds themselves lead to water uptake, and organic compounds interact with water associated with inorganic compounds in the rural southeast atmosphere. Including interactions of organic compounds with water requires a treatment of nonideality to more accurately represent aerosol observations during the Southern Oxidant and Aerosol Study (SOAS) 2013.
Neha Sareen, Annmarie G. Carlton, Jason D. Surratt, Avram Gold, Ben Lee, Felipe D. Lopez-Hilfiker, Claudia Mohr, Joel A. Thornton, Zhenfa Zhang, Yong B. Lim, and Barbara J. Turpin
Atmos. Chem. Phys., 16, 14409–14420, https://doi.org/10.5194/acp-16-14409-2016, https://doi.org/10.5194/acp-16-14409-2016, 2016
P. L. Hayes, A. G. Carlton, K. R. Baker, R. Ahmadov, R. A. Washenfelder, S. Alvarez, B. Rappenglück, J. B. Gilman, W. C. Kuster, J. A. de Gouw, P. Zotter, A. S. H. Prévôt, S. Szidat, T. E. Kleindienst, J. H. Offenberg, P. K. Ma, and J. L. Jimenez
Atmos. Chem. Phys., 15, 5773–5801, https://doi.org/10.5194/acp-15-5773-2015, https://doi.org/10.5194/acp-15-5773-2015, 2015
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(1) Four different parameterizations for the formation and chemical evolution of secondary organic aerosol (SOA) are evaluated using a box model representing the Los Angeles region during the CalNex campaign.
(2) The SOA formed only from the oxidation of VOCs is insufficient to explain the observed SOA concentrations.
(3) The amount of SOA mass formed from diesel vehicle emissions is estimated to be 16-27%.
(4) Modeled SOA depends strongly on the P-S/IVOC volatility distribution.
C. J. Hennigan, J. Izumi, A. P. Sullivan, R. J. Weber, and A. Nenes
Atmos. Chem. Phys., 15, 2775–2790, https://doi.org/10.5194/acp-15-2775-2015, https://doi.org/10.5194/acp-15-2775-2015, 2015
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We show that the ion balance and molar ratio methods are unsuitable for use as aerosol pH proxies. Our recommendation is that 1) thermodynamic equilibrium models constrained by both gas and aerosol inputs run in the forward (open) mode, and 2) the phase partitioning of ammonia provides the best predictions of aerosol pH. Given the significance of acidity for numerous chemical processes in the atmosphere, the implications of this study are important and far reaching.
K. C. Barsanti, A. G. Carlton, and S. H. Chung
Atmos. Chem. Phys., 13, 12073–12088, https://doi.org/10.5194/acp-13-12073-2013, https://doi.org/10.5194/acp-13-12073-2013, 2013
A. G. Carlton and B. J. Turpin
Atmos. Chem. Phys., 13, 10203–10214, https://doi.org/10.5194/acp-13-10203-2013, https://doi.org/10.5194/acp-13-10203-2013, 2013
R. Saleh, C. J. Hennigan, G. R. McMeeking, W. K. Chuang, E. S. Robinson, H. Coe, N. M. Donahue, and A. L. Robinson
Atmos. Chem. Phys., 13, 7683–7693, https://doi.org/10.5194/acp-13-7683-2013, https://doi.org/10.5194/acp-13-7683-2013, 2013
C. He, J. Liu, A. G. Carlton, S. Fan, L. W. Horowitz, H. Levy II, and S. Tao
Atmos. Chem. Phys., 13, 1913–1926, https://doi.org/10.5194/acp-13-1913-2013, https://doi.org/10.5194/acp-13-1913-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
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Direct measurement of N2O5 heterogeneous uptake coefficients on atmospheric aerosols in southwestern China and evaluation of current parameterizations
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Effects of Anthropogenic Pollutants on Biogenic Secondary Organic Aerosol Formation in the Atmosphere of Mt. Hua, China
Marine organic aerosol at Mace Head: effects from phytoplankton and source region variability
Elemental composition, iron mineralogy and solubility of anthropogenic and natural mineral dust aerosols in Namibia: a case study analysis from the AEROCLO-sA campaign
Fossil-Dominated SOA Formation in Coastal China: Size-Divergent Pathways of Aqueous Fenton Reactions versus Gas-phase VOC Autoxidation
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Hydroxymethanesulfonate (HMS) Formation under Urban and Marine Atmosphere: role of aerosol ionic strength
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Non-biogenic sources are an important but overlooked contributor to aerosol isoprene-derived organosulfates during winter in northern China
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The critical role of aqueous-phase processes in aromatic-derived nitrogen-containing organic aerosol formation in cities with different energy consumption patterns
Characterization of atmospheric water-soluble brown carbon in the Athabasca oil sands region, Canada
Sensitivity of aerosol and cloud properties to coupling strength of marine boundary layer clouds over the northwest Atlantic
Measurement Report: Molecular composition, sources, and evolution of atmospheric organic aerosols in a basin city in China
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Observations of high-time-resolution and size-resolved aerosol chemical composition and microphysics in the central Arctic: implications for climate-relevant particle properties
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Measurement Report: Polycyclic aromatic hydrocarbons (PAHs) and their alkylated (RPAHs), nitrated (NPAHs) and oxygenated (OPAHs) derivatives in the global marine atmosphere: occurrence, spatial variations, and source apportionment
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Atmos. Chem. Phys., 25, 8185–8211, https://doi.org/10.5194/acp-25-8185-2025, https://doi.org/10.5194/acp-25-8185-2025, 2025
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This work advances our understanding of the emission and atmospheric evolution of black carbon (BC) particles in Singapore, a complex urban environment impacted by multiple local and regional combustion sources, based on the improved source apportionment analysis of real-time aerosol mass spectrometry measurement.
Capucine Camin, François Lacan, Catherine Pradoux, Marie Labatut, Anne Johansen, and James W. Murray
Atmos. Chem. Phys., 25, 8213–8228, https://doi.org/10.5194/acp-25-8213-2025, https://doi.org/10.5194/acp-25-8213-2025, 2025
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This paper presents the chemical and iron isotopic composition of aerosols (> 1 µm) over the equatorial and tropical Pacific Ocean in previously undocumented areas. Analysis of our data suggests that a significant proportion of aerosol iron (∼ 13 %) is not only dissolved but also removed during atmospheric transport. Such removal had not previously been evidenced to our knowledge. This highlights the unique and strong constraints brought by iron isotopes on atmospheric process studies.
Fredrik Mattsson, Almuth Neuberger, Liine Heikkinen, Yvette Gramlich, Marco Paglione, Matteo Rinaldi, Stefano Decesari, Paul Zieger, Ilona Riipinen, and Claudia Mohr
Atmos. Chem. Phys., 25, 7973–7989, https://doi.org/10.5194/acp-25-7973-2025, https://doi.org/10.5194/acp-25-7973-2025, 2025
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This study investigated aerosol–cloud interactions, focusing on organic nitrogen (ON) formation in the aqueous phase. Measurements were conducted in wintertime in the Po Valley, Italy, using aerosol mass spectrometry. The fog was enriched in more hygroscopic inorganic compounds and ON, containing, e.g., imidazoles. The formation of imidazole by aerosol–fog interactions could be confirmed for the first time in atmospheric observations. Findings highlight the role of fog in nitrogen aerosol formation.
Ren-Guo Zhu, Hua-Yun Xiao, Meiju Yin, Hao Xiao, Zhongkui Zhou, Yuanyuan Pan, Guo Wei, and Cheng Liu
Atmos. Chem. Phys., 25, 7699–7718, https://doi.org/10.5194/acp-25-7699-2025, https://doi.org/10.5194/acp-25-7699-2025, 2025
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The concentrations and δ15N isotopic values of CAAs (combined amino acids) in surface soil and plants from the Gobi Desert, as well as in PM2.5 samples from four cities in Northern China, were measured. CAAs transported by Gobi dust were rich in alanine, glycine and glutamic acid. Glycine and leucine in Gobi Desert sources exhibited δ15N depletion by more than 6 ‰ compared to their values in urban PM2.5. Substantial protein-N deposition can be transported by the Gobi Desert to northern China over brief periods.
Yu Huang, Xingru Li, Dan Dan Huang, Ruoyuan Lei, Binhuang Zhou, Yunjiang Zhang, and Xinlei Ge
Atmos. Chem. Phys., 25, 7619–7645, https://doi.org/10.5194/acp-25-7619-2025, https://doi.org/10.5194/acp-25-7619-2025, 2025
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This work comprises a comprehensive investigation into the chemical and optical properties of brown carbon (BrC) in PM2.5 samples collected in Nanjing, China. In particular, we used a machine learning approach to identify a list of key BrC species, which can be a good reference for future studies. Our findings extend understanding of BrC properties and are valuable to the assessment of BrC's impact on air quality and radiative forcing.
Qingxiao Meng, Yunjiang Zhang, Sheng Zhong, Jie Fang, Lili Tang, Yongcai Rao, Minfeng Zhou, Jian Qiu, Xiaofeng Xu, Jean-Eudes Petit, Olivier Favez, and Xinlei Ge
Atmos. Chem. Phys., 25, 7485–7498, https://doi.org/10.5194/acp-25-7485-2025, https://doi.org/10.5194/acp-25-7485-2025, 2025
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We developed a machine-learning-based method to reconstruct missing elemental carbon (EC) data in four Chinese cities from 2013 to 2023. Using machine learning, we filled data gaps and introduced a new approach to analyze EC trends. Our findings reveal a significant decline in EC due to stricter pollution controls, though this slowed after 2020. This study provides a versatile framework for addressing data gaps and supports strategies to reduce urban air pollution and its climate impacts.
Binyu Xiao, Fan Zhang, Zeyu Liu, Yan Zhang, Rui Li, Can Wu, Xinyi Wan, Yi Wang, Yubao Chen, Yong Han, Min Cui, Libo Zhang, Yingjun Chen, and Gehui Wang
Atmos. Chem. Phys., 25, 7053–7069, https://doi.org/10.5194/acp-25-7053-2025, https://doi.org/10.5194/acp-25-7053-2025, 2025
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Intermediate-volatility/semi-volatile organic compounds in gas and particle phases from ship exhausts are enhanced due to the switch of fuels from low sulfur to ultra-low sulfur. The findings indicate that optimization is necessary for the forthcoming global implementation of an ultra-low-sulfur oil policy. Besides, we find that organic diagnostic markers of hopanes in conjunction with the ratio of octadecanoic to tetradecanoic could be considered potential tracers for heavy fuel oil exhausts.
Hongyu Zhang, Shenbo Wang, Zhangsen Dong, Xiao Li, and Ruiqin Zhang
Atmos. Chem. Phys., 25, 6943–6955, https://doi.org/10.5194/acp-25-6943-2025, https://doi.org/10.5194/acp-25-6943-2025, 2025
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Analyzing 12-year Zhengzhou data revealed post-2019 crustal material rebound caused by soil dust resuspension, elevating particle pH. Similar coarse particle increases are observed across cities of the North China Plain. Long-term particle acidity evolution in this region requires an integrated assessment of interactions among acidic precursors, ammonia, and crustal components.
Yanqin Ren, Zhenhai Wu, Fang Bi, Hong Li, Haijie Zhang, Junling Li, Rui Gao, Fangyun Long, Zhengyang Liu, Yuanyuan Ji, and Gehui Wang
Atmos. Chem. Phys., 25, 6975–6990, https://doi.org/10.5194/acp-25-6975-2025, https://doi.org/10.5194/acp-25-6975-2025, 2025
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The daily concentrations of Polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs (OPAHs), and nitrated phenols (NPs) in PM2.5 were all increased during the heating season. Biomass burning was identified to be the primary source of these aromatic compounds, particularly for PAHs. Phenol and nitrobenzene are two main primary precursors for 4NP, with phenol showing lower reaction barriers. P-Cresol was identified as the primary precursor for the formation of 4-methyl-5-nitrocatechol.
Lise Le Berre, Brice Temime-Roussel, Grazia Maria Lanzafame, Barbara D'Anna, Nicolas Marchand, Stéphane Sauvage, Marvin Dufresne, Liselotte Tinel, Thierry Leonardis, Joel Ferreira de Brito, Alexandre Armengaud, Grégory Gille, Ludovic Lanzi, Romain Bourjot, and Henri Wortham
Atmos. Chem. Phys., 25, 6575–6605, https://doi.org/10.5194/acp-25-6575-2025, https://doi.org/10.5194/acp-25-6575-2025, 2025
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A summer campaign in a Mediterranean port examined pollution caused by ships. Two stations in the port measured pollution levels and captured over 350 ship plumes to study their chemical composition. Results showed that pollution levels, such as ultra-fine particles, were higher in the port than in the city and offer strong support to improve emission inventories. These findings may also serve as reference to assess the benefits of a sulfur Emission Control Area in the Mediterranean in 2025.
Jiayin Li, Tianyu Zhai, Xiaorui Chen, Haichao Wang, Shuyang Xie, Shiyi Chen, Chunmeng Li, Yuanjun Gong, Huabin Dong, and Keding Lu
Atmos. Chem. Phys., 25, 6395–6406, https://doi.org/10.5194/acp-25-6395-2025, https://doi.org/10.5194/acp-25-6395-2025, 2025
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We directly measured the dinitrogen pentoxide (N2O5) uptake coefficient using an aerosol flow tube, which critically impacts the NOx fate and particulate nitrate formation in a typical highland city, Kunming, in China. We found that the performance of current γ (N2O5) parameterizations showed deviations with the varying aerosol liquid water content (ALWC). Such differences would lead to biased estimation of particulate nitrate production potential. We give suggestions for future research directions.
Jishnu Pandamkulangara Kizhakkethil, Zongbo Shi, Anna Bogush, and Ivan Kourtchev
Atmos. Chem. Phys., 25, 5947–5958, https://doi.org/10.5194/acp-25-5947-2025, https://doi.org/10.5194/acp-25-5947-2025, 2025
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Pollution with per- and polyfluoroalkyl substances (PFAS) has received attention due to their environmental persistence and bioaccumulation, but their sources remain poorly understood. PM10 (particulate matter) collected above a scaled-down activated sludge tank treating domestic sewage in the UK was analysed for a range of short-, medium-, and long-chain PFAS. Eight PFAS were detected in the PM10. Our results suggest that wastewater treatment processes, i.e. activated sludge aeration, could aerosolise PFAS into airborne PM.
Haley M. Royer, Michael T. Sheridan, Hope E. Elliott, Edmund Blades, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Zihua Zhu, Andrew P. Ault, and Cassandra J. Gaston
Atmos. Chem. Phys., 25, 5743–5759, https://doi.org/10.5194/acp-25-5743-2025, https://doi.org/10.5194/acp-25-5743-2025, 2025
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Saharan dust transported across the Atlantic to the Caribbean, South America, and North America is hypothesized to undergo chemical processing by acids that enhances cloud droplet formation and nutrient availability. In this study, chemical analysis performed on African dust deposited over Barbados shows that acid tracers are found mostly on sea salt and smoke particles, rather than dust, indicating that dust particles undergo minimal chemical processing.
Zhao Wei, Shohei Hattori, Asuka Tsuruta, Zhuang Jiang, Sakiko Ishino, Koji Fujita, Sumito Matoba, Lei Geng, Alexis Lamothe, Ryu Uemura, Naohiro Yoshida, Joel Savarino, and Yoshinori Iizuka
Atmos. Chem. Phys., 25, 5727–5742, https://doi.org/10.5194/acp-25-5727-2025, https://doi.org/10.5194/acp-25-5727-2025, 2025
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Nitrate isotope records in ice cores reveal changes in NOₓ emissions and atmospheric oxidation chemistry driven by human activity. However, UV-driven postdepositional processes can alter nitrate in snow, making snow accumulation rates critical for preserving these records. This study examines nitrate isotopes in a southeastern Greenland ice core, where high snow accumulation minimizes these effects, providing a reliable archive of atmospheric nitrogen cycling.
Genevieve Rose Lorenzo, Luke D. Ziemba, Avelino F. Arellano, Mary C. Barth, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Richard Ferrare, Miguel Ricardo A. Hilario, Michael A. Shook, Simone Tilmes, Jian Wang, Qian Xiao, Jun Zhang, and Armin Sorooshian
Atmos. Chem. Phys., 25, 5469–5495, https://doi.org/10.5194/acp-25-5469-2025, https://doi.org/10.5194/acp-25-5469-2025, 2025
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Novel aerosol hygroscopicity analyses of CAMP2Ex (Cloud, Aerosol, and Monsoon Processes Philippines Experiment) field campaign data show low aerosol hygroscopicity values in Southeast Asia. Organic carbon from smoke decreases hygroscopicity to levels more like those in continental than in polluted marine regions. Hygroscopicity changes at cloud level demonstrate how surface particles impact clouds in the region, affecting model representation of aerosol and cloud interactions in similar polluted marine regions with high organic carbon emissions.
Kouji Adachi, Atsushi Yoshida, Tatsuhiro Mori, Nobuhiro Moteki, Sho Ohata, Kazuyuki Kita, Yoshimi Kawai, and Makoto Koike
EGUsphere, https://doi.org/10.5194/egusphere-2025-2230, https://doi.org/10.5194/egusphere-2025-2230, 2025
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This study measured the compositions and mixing states of individual aerosol particles collected at different altitudes over the western North Pacific by simultaneous sampling from an aircraft and a research vessel. The results showed that they were strongly influenced by Siberian Forest biomass burning and mixed with sea spray, and identified various aerosol compositions at different altitudes, sizes, and aerosol sources, highlighting a wide range of individual particle compositions.
Diana L. Pereira, Chiara Giorio, Aline Gratien, Alexander Zherebker, Gael Noyalet, Servanne Chevaillier, Stéphanie Alage, Elie Almarj, Antonin Bergé, Thomas Bertin, Mathieu Cazaunau, Patrice Coll, Ludovico Di Antonio, Sergio Harb, Johannes Heuser, Cécile Gaimoz, Oscar Guillemant, Brigitte Language, Olivier Lauret, Camilo Macias, Franck Maisonneuve, Bénédicte Picquet-Varrault, Raquel Torres, Sylvain Triquet, Pascal Zapf, Lelia Hawkins, Drew Pronovost, Sydney Riley, Pierre-Marie Flaud, Emilie Perraudin, Pauline Pouyes, Eric Villenave, Alexandre Albinet, Olivier Favez, Robin Aujay-Plouzeau, Vincent Michoud, Christopher Cantrell, Manuela Cirtog, Claudia Di Biagio, Jean-François Doussin, and Paola Formenti
Atmos. Chem. Phys., 25, 4885–4905, https://doi.org/10.5194/acp-25-4885-2025, https://doi.org/10.5194/acp-25-4885-2025, 2025
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In order to study aerosols in environments influenced by anthropogenic and biogenic emissions, we performed analyses of samples collected during the ACROSS (Atmospheric Chemistry Of the Suburban Forest) campaign in summer 2022 in the greater Paris area. After analysis of the chemical composition by means of total carbon determination and high-resolution mass spectrometry, this work highlights the influence of anthropogenic inputs on the chemical composition of both urban and forested areas.
Kimmo Teinilä, Sanna Saarikoski, Henna Lintusaari, Teemu Lepistö, Petteri Marjanen, Minna Aurela, Heidi Hellén, Toni Tykkä, Markus Lampimäki, Janne Lampilahti, Luis Barreira, Timo Mäkelä, Leena Kangas, Juha Hatakka, Sami Harni, Joel Kuula, Jarkko V. Niemi, Harri Portin, Jaakko Yli-Ojanperä, Ville Niemelä, Milja Jäppi, Katrianne Lehtipalo, Joonas Vanhanen, Liisa Pirjola, Hanna E. Manninen, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 25, 4907–4928, https://doi.org/10.5194/acp-25-4907-2025, https://doi.org/10.5194/acp-25-4907-2025, 2025
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Physical and chemical properties of particulate matter and concentrations of trace gases were measured in a street canyon in Helsinki, Finland, and an urban background site in January–February 2022 to investigate the effect of wintertime conditions on pollutants. State-of-the-art instruments and a mobile laboratory were used, and the measurement data were analysed further with modelling tools like positive matrix factorization and the Pollution Detection Algorithm.
Guilherme Martins Pereira, Leonardo Yoshiaki Kamigauti, Rubens Fabio Pereira, Djacinto Monteiro dos Santos, Thayná da Silva Santos, José Vinicius Martins, Célia Alves, Cátia Gonçalves, Ismael Casotti Rienda, Nora Kováts, Thiago Nogueira, Luciana Rizzo, Paulo Artaxo, Regina Maura de Miranda, Marcia Akemi Yamasoe, Edmilson Dias de Freitas, Pérola de Castro Vasconcellos, and Maria de Fatima Andrade
Atmos. Chem. Phys., 25, 4587–4616, https://doi.org/10.5194/acp-25-4587-2025, https://doi.org/10.5194/acp-25-4587-2025, 2025
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The chemical composition of fine particulate matter was studied in the megacity of São Paulo (Brazil) during a polluted period. Vehicular-related sources remain relevant; however, a high contribution of biomass burning was observed and correlated with sample ecotoxicity. Emerging biomass burning sources, such as forest fires and sugarcane-bagasse-based power plants, highlight the need for additional control measures alongside stricter rules concerning vehicular emissions.
Tao Qiu, Yanting Qiu, Yongyi Yuan, Rui Su, Xiangxinyue Meng, Jialiang Ma, Xiaofan Wang, Yu Gu, Zhijun Wu, Yang Ning, Xiuyi Hua, Dapeng Liang, and Deming Dong
EGUsphere, https://doi.org/10.5194/egusphere-2025-1808, https://doi.org/10.5194/egusphere-2025-1808, 2025
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Our research reveals that some species from biomass burning and coal combustion dominate the light absorption of organic aerosols during winter. Cold weather helps these species accumulate in aerosols by slowing their degradation and altering atmospheric chemical processes. This means colder regions might experience stronger and more persistent climate impacts. Our findings highlight the importance of local temperatures and pollution sources when tackling climate challenges.
Can Wu, Yubao Chen, Yuwei Sun, Huijun Zhang, Si Zhang, Cong Cao, Jianjun Li, and Gehui Wang
EGUsphere, https://doi.org/10.5194/egusphere-2025-1668, https://doi.org/10.5194/egusphere-2025-1668, 2025
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Biogenic secondary organic aerosol (BSOA), as an important atmospheric component, is prevalent within the boundary layer and can influence air quality and human health. Our observations demonstrate that anthropogenic NOx and the enhanced aerosol water driven by sulfate inhibit BSOA formation in lifting air masses, leading to a moderate reduction in the SOA burden in the upper boundary layer.
Emmanuel Chevassus, Kirsten N. Fossum, Darius Ceburnis, Lu Lei, Chunshui Lin, Wei Xu, Colin O'Dowd, and Jurgita Ovadnevaite
Atmos. Chem. Phys., 25, 4107–4129, https://doi.org/10.5194/acp-25-4107-2025, https://doi.org/10.5194/acp-25-4107-2025, 2025
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This study presents the first source apportionment of organic aerosol at Mace Head via high-resolution mass spectrometry. Introducing transfer entropy as a novel method reveals that aged organic aerosol originates from both open-ocean ozonolysis and local peat-burning oxidation. Methanesulfonic acid and organic sea spray both mirror phytoplankton activity, with the former closely tied to coccolithophore blooms and the latter linked to diatoms, chlorophytes, and cyanobacteria.
Paola Formenti, Chiara Giorio, Karine Desboeufs, Alexander Zherebker, Marco Gaetani, Clarissa Baldo, Gautier Landrot, Simona Montebello, Servanne Chevaillier, Sylvain Triquet, Guillaume Siour, Claudia Di Biagio, Francesco Battaglia, Jean-François Doussin, Anais Feron, Andreas Namwoonde, and Stuart John Piketh
EGUsphere, https://doi.org/10.5194/egusphere-2025-446, https://doi.org/10.5194/egusphere-2025-446, 2025
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The elemental composition and solubility of several metals, including iron, at a coastal site in Namibia in August–September 2017, indicate that natural and anthropogenic dust had different solubility depending on mineralogy but mostly to the processing by fluoride ions from marine emissions, pointing out to the complexity of atmospheric/oceanic interactions in this region of the world influenced by the Benguela current and significant aerosol load.
Jia-Yuan Wang, Meng-Xue Tang, Shan Lu, Ke-Jin Tang, Xing Peng, Ling-Yan He, and Xiao-Feng Huang
EGUsphere, https://doi.org/10.5194/egusphere-2025-1034, https://doi.org/10.5194/egusphere-2025-1034, 2025
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Our study explores how secondary organic aerosols (SOA), a major component of air pollution, form in different particle sizes in a coastal city in China. We found that SOA in fine particles is mainly produced through aqueous chemical reactions, especially those involving iron. In contrast, coarse particles form SOA through reactions with ozone and gases from both fossil fuels and natural sources. These findings highlight the need for size-specific air pollution models.
Ashutosh K. Shukla, Sachchida N. Tripathi, Shamitaksha Talukdar, Vishnu Murari, Sreenivas Gaddamidi, Manousos-Ioannis Manousakas, Vipul Lalchandani, Kuldeep Dixit, Vinayak M. Ruge, Peeyush Khare, Mayank Kumar, Vikram Singh, Neeraj Rastogi, Suresh Tiwari, Atul K. Srivastava, Dilip Ganguly, Kaspar Rudolf Daellenbach, and André S. H. Prévôt
Atmos. Chem. Phys., 25, 3765–3784, https://doi.org/10.5194/acp-25-3765-2025, https://doi.org/10.5194/acp-25-3765-2025, 2025
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Our study delves into the elemental composition of aerosols at three sites across the Indo-Gangetic Plain (IGP), revealing distinct patterns during pollution episodes. We found significant increases in chlorine (Cl)-rich and solid fuel combustion (SFC) sources, indicating dynamic emission sources, agricultural burning impacts, and meteorological influences. Surges in Cl-rich particles during cold periods highlight their role in particle growth under high-relative-humidity conditions.
Ye Kuang, Biao Luo, Shan Huang, Junwen Liu, Weiwei Hu, Yuwen Peng, Duohong Chen, Dingli Yue, Wanyun Xu, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 25, 3737–3752, https://doi.org/10.5194/acp-25-3737-2025, https://doi.org/10.5194/acp-25-3737-2025, 2025
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This research reveals the potential importance of nighttime NO3 radical chemistry and aerosol water in the rapid formation of secondary brown carbon from diluted biomass burning emissions. The findings enhance our understanding of nighttime biomass burning evolution and its implications for climate and regional air quality, especially regarding interactions with background aerosol water and water-rich fogs and clouds.
Rongshuang Xu, Yu-Chi Lin, Siyu Bian, Feng Xie, and Yan-Lin Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2025-683, https://doi.org/10.5194/egusphere-2025-683, 2025
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This work reported the hydroxymethanesulfonate (HMS) level in a continental city and, for the first time, in marine atmosphere. The enhancement by aerosol ionic strength (IS) on HMS formation was quantified which first rise with increasing IS, peaking at 4 mol kg–1 before declining. Given the IS range of marine (2–6) and urban aerosol (6–20 mol kg–1) and the clearly negative correlation between humidity and IS, the moderate IS level under humid condition may notably boost ambient HMS formation.
Fan Mei, Qi Zhang, Damao Zhang, Jerome D. Fast, Gourihar Kulkarni, Mikhail S. Pekour, Christopher R. Niedek, Susanne Glienke, Israel Silber, Beat Schmid, Jason M. Tomlinson, Hardeep S. Mehta, Xena Mansoura, Zezhen Cheng, Gregory W. Vandergrift, Nurun Nahar Lata, Swarup China, and Zihua Zhu
Atmos. Chem. Phys., 25, 3425–3444, https://doi.org/10.5194/acp-25-3425-2025, https://doi.org/10.5194/acp-25-3425-2025, 2025
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This study highlights the unique capability of the ArcticShark, an uncrewed aerial system, in measuring vertically resolved atmospheric properties. Data from 32 research flights in 2023 reveal seasonal patterns and correlations with conventional measurements. The consistency and complementarity of in situ and remote sensing methods are highlighted. The study demonstrates the ArcticShark’s versatility in bridging data gaps and improving the understanding of vertical atmospheric structures.
Yuan Cheng, Ying-jie Zhong, Zhi-qing Zhang, Xu-bing Cao, and Jiu-meng Liu
EGUsphere, https://doi.org/10.5194/egusphere-2025-537, https://doi.org/10.5194/egusphere-2025-537, 2025
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As an emerging hotspot of atmospheric sciences, Northeast China is distinct due to the frigid winter and the strong emissions from agricultural fires. Based on field campaigns conducted in Harbin, we successively identified the analytical method that could lead to proper results of organic and elemental carbon. Our results are believed to be a support for future efforts on exploration of the PM2.5 sources in Northeast China, which are essential for further improving the regional air quality.
Ting Yang, Yu Xu, Yu-Chen Wang, Yi-Jia Ma, Hong-Wei Xiao, Hao Xiao, and Hua-Yun Xiao
Atmos. Chem. Phys., 25, 2967–2978, https://doi.org/10.5194/acp-25-2967-2025, https://doi.org/10.5194/acp-25-2967-2025, 2025
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Previous measurement–model comparisons of atmospheric isoprene levels showed a significant unidentified source of isoprene in some northern Chinese cities during winter. Here, the first combination of large-scale observations and field combustion experiments provides novel insights into biomass burning emissions as a significant source of isoprene-derived organosulfates during winter in northern cities of China.
Agnesh Panta, Konrad Kandler, Kerstin Schepanski, Andres Alastuey, Pavla Dagsson Waldhauserova, Sylvain Dupont, Melanie Eknayan, Cristina González-Flórez, Adolfo González-Romero, Martina Klose, Mara Montag, Xavier Querol, Jesús Yus-Díez, and Carlos Pérez García-Pando
EGUsphere, https://doi.org/10.5194/egusphere-2025-494, https://doi.org/10.5194/egusphere-2025-494, 2025
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Iceland is among the most active dust source areas in the world. Dust properties are influenced by particle size, mineralogy, shape, and mixing state. This work characterizes freshly emitted individual aerosol particles of Icelandic dust using electron microscopy. Our study provides insights into critical particle-specific information will contribute to better constraining climate models that consider mineralogical variations in their representation of the dust cycle.
Xueqin Zheng, Junwen Liu, Nima Chuduo, Bian Ba, Pengfei Yu, Phu Drolgar, Fang Cao, and Yanlin Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2025-164, https://doi.org/10.5194/egusphere-2025-164, 2025
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In this study, we present the first report on the annual variation of stable oxygen isotope anomalies (∆17O = δ17O - 0.52 × δ18O) in NO3- collected from the urban area of Lhasa , on the Tibetan Plateau, China. Using a Bayesian isotope mixture model, we found that the relative contribution of the NO3+VOC pathway to NO3- formation in spring in Lhasa was several times higher than in urban cities, highlighting the significant influence of VOC transported from outside the Tibetan Plateau.
Yi-Jia Ma, Yu Xu, Ting Yang, Lin Gui, Hong-Wei Xiao, Hao Xiao, and Hua-Yun Xiao
Atmos. Chem. Phys., 25, 2763–2780, https://doi.org/10.5194/acp-25-2763-2025, https://doi.org/10.5194/acp-25-2763-2025, 2025
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The abundance, potential precursors, and main formation mechanisms of nitrogen-containing organic compounds (NOCs) in PM2.5 during winter were compared among cities with different energy consumption patterns. The aerosol NOC pollution during winter in China is closely associated with the intensity of precursor emissions and the aqueous-phase processes. Our results highlight the importance of emission reduction strategies in controlling aerosol NOCs pollution during winter in China.
Dane Blanchard, Mark Gordon, Duc Huy Dang, Paul Andrew Makar, and Julian Aherne
Atmos. Chem. Phys., 25, 2423–2442, https://doi.org/10.5194/acp-25-2423-2025, https://doi.org/10.5194/acp-25-2423-2025, 2025
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This study offers the first known evaluation of water-soluble brown carbon aerosols in the Athabasca oil sands region (AOSR), Canada. Fluorescence spectroscopy analysis of aerosol samples from five regional sites (collected during the summer of 2021) identified oil sands operations as a measurable brown carbon source. Industrial aerosol emissions were unlikely to impact regional radiative forcing. These findings show that fluorescence spectroscopy can be used to monitor brown carbon in the AOSR.
Kira Zeider, Kayla McCauley, Sanja Dmitrovic, Leong Wai Siu, Yonghoon Choi, Ewan C. Crosbie, Joshua P. DiGangi, Glenn S. Diskin, Simon Kirschler, John B. Nowak, Michael A. Shook, Kenneth L. Thornhill, Christiane Voigt, Edward L. Winstead, Luke D. Ziemba, Paquita Zuidema, and Armin Sorooshian
Atmos. Chem. Phys., 25, 2407–2422, https://doi.org/10.5194/acp-25-2407-2025, https://doi.org/10.5194/acp-25-2407-2025, 2025
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In situ aircraft data collected over the northwest Atlantic Ocean are utilized to compare aerosol conditions and turbulence between near-surface and below-cloud-base altitudes for different regimes of coupling strength between those two levels, along with how cloud microphysical properties vary across those regimes. Stronger coupling yields more homogenous aerosol structure vertically along with higher cloud drop concentrations and sea salt influence in clouds.
Junke Zhang, Xinyi Fu, Chunying Chen, Yunfei Su, Siyu Liu, Luyao Chen, Yubao Chen, Gehui Wang, and Andre S. H. Prevot
EGUsphere, https://doi.org/10.5194/egusphere-2025-92, https://doi.org/10.5194/egusphere-2025-92, 2025
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The 125 organic aerosol (OA) compounds in PM2.5 in winter in Chengdu were measured at the molecular level. OA was dominated by fatty acids, phthalate esters, and anhydrosugars, and were deeply influenced by anthropogenic sources. As pollution worsens: secondary inorganic species and secondary organic carbon (OC) dominated the increase in PM2.5; fatty acids and anhydrosugars dominated the increase in OA; and the contribution of secondary formation and biomass burning to OC increased markedly.
Amie Dobracki, Ernie R. Lewis, Arthur J. Sedlacek III, Tyler Tatro, Maria A. Zawadowicz, and Paquita Zuidema
Atmos. Chem. Phys., 25, 2333–2363, https://doi.org/10.5194/acp-25-2333-2025, https://doi.org/10.5194/acp-25-2333-2025, 2025
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Biomass-burning aerosol is commonly present in the marine boundary layer over the southeast Atlantic Ocean between June and October. Our research indicates that burning conditions, aerosol transport pathways, and prolonged oxidation processes (heterogeneous and aqueous phases) determine the chemical, microphysical, and optical properties of the boundary layer aerosol. Notably, we find that the aerosol optical properties can be estimated from the chemical properties alone.
Benjamin Heutte, Nora Bergner, Hélène Angot, Jakob B. Pernov, Lubna Dada, Jessica A. Mirrielees, Ivo Beck, Andrea Baccarini, Matthew Boyer, Jessie M. Creamean, Kaspar R. Daellenbach, Imad El Haddad, Markus M. Frey, Silvia Henning, Tiia Laurila, Vaios Moschos, Tuukka Petäjä, Kerri A. Pratt, Lauriane L. J. Quéléver, Matthew D. Shupe, Paul Zieger, Tuija Jokinen, and Julia Schmale
Atmos. Chem. Phys., 25, 2207–2241, https://doi.org/10.5194/acp-25-2207-2025, https://doi.org/10.5194/acp-25-2207-2025, 2025
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Limited aerosol measurements in the central Arctic hinder our understanding of aerosol–climate interactions in the region. Our year-long observations of aerosol physicochemical properties during the MOSAiC expedition reveal strong seasonal variations in aerosol chemical composition, where the short-term variability is heavily affected by storms in the Arctic. Local wind-generated particles are shown to be an important source of cloud seeds, especially in autumn.
Feng Jiang, Harald Saathoff, Uzoamaka Ezenobi, Junwei Song, Hengheng Zhang, Linyu Gao, and Thomas Leisner
Atmos. Chem. Phys., 25, 1917–1930, https://doi.org/10.5194/acp-25-1917-2025, https://doi.org/10.5194/acp-25-1917-2025, 2025
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The chemical composition of brown carbon in the particle and gas phase was determined by mass spectrometry. BrC in the gas phase was mainly controlled by secondary formation and particle-to-gas partitioning. BrC in the particle phase was mainly from secondary formation. This work helps to get a better understanding of diurnal variations and the sources of brown carbon aerosol at a rural location in central Europe.
Theresa Mathes, Heather Guy, John Prytherch, Julia Kojoj, Ian Brooks, Sonja Murto, Paul Zieger, Birgit Wehner, Michael Tjernström, and Andreas Held
EGUsphere, https://doi.org/10.5194/egusphere-2025-183, https://doi.org/10.5194/egusphere-2025-183, 2025
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The Arctic is warming faster than the global average and aerosol-cloud-sea-ice interactions are crucial for studying its climate system. During the ARTofMELT Expedition 2023, particle and sensible heat fluxes were measured over multiple surfaces. Wide lead surfaces acted as particle sources with the strongest sensible heat fluxes, while closed ice surfaces acted as a particle sink. This study improves methods to measure these interactions, enhancing our understanding of Arctic climate processes.
Vikram Pratap, Christopher J. Hennigan, Bastian Stieger, Andreas Tilgner, Laurent Poulain, Dominik van Pinxteren, Gerald Spindler, and Hartmut Herrmann
EGUsphere, https://doi.org/10.5194/egusphere-2025-457, https://doi.org/10.5194/egusphere-2025-457, 2025
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In this work, we characterize trends in aerosol pH and its controlling factors over the period of 2010 – 2019 at the Melpitz research station in eastern Germany. We find strong trends in aerosol pH and major inorganic species in response to changing emissions. We conduct a detailed thermodynamic analysis of the aerosol system and discuss implications for controlling PM2.5 in the region.
Kohei Sakata, Shotaro Takano, Atsushi Matsuki, Yasuo Takeichi, Hiroshi Tanimoto, Aya Sakaguchi, Minako Kurisu, and Yoshio Takahashi
EGUsphere, https://doi.org/10.5194/egusphere-2025-161, https://doi.org/10.5194/egusphere-2025-161, 2025
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Deposition of aerosol iron (Fe) into the ocean stimulates primary production and influences the global carbon cycle, although the factors governing the aerosol Fe solubility remain uncertain. Our observations in Japan revealed that both mineral dust and anthropogenic aerosols are significant sources of dissolved Fe, and that atmospheric chemical weathering enhances their solubility. This finding is expected to play a crucial role in estimating the supply of dissolved iron to the ocean.
Rui Li, Yubing Shen, Yumeng Shao, Yining Gao, Ziwei Yao, Qian Liu, Xing Liu, and Guitao Shi
EGUsphere, https://doi.org/10.5194/egusphere-2024-3740, https://doi.org/10.5194/egusphere-2024-3740, 2025
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It is the first time to reveal the global variations of PAHs derivatives in the marine air. We found that marine aerosols in East China Sea (ECS) and Western Pacific (WP) were significantly affected by coal and engine combustion, while those in Bismarck Sea (BS) and East Australian Sea (EAS) were mainly influenced by wildfire and coal combustion. Antarctic Ocean (AO) was dominated by biomass burning and local shipping emissions. This finding help elucidate the mechanism of global PAH cycle.
James Brean, David C. S. Beddows, Eija Asmi, Aki Virkkula, Lauriane L. J. Quéléver, Mikko Sipilä, Floortje Van Den Heuvel, Thomas Lachlan-Cope, Anna Jones, Markus Frey, Angelo Lupi, Jiyeon Park, Young Jun Yoon, Rolf Weller, Giselle L. Marincovich, Gabriela C. Mulena, Roy M. Harrison, and Manuel Dall'Osto
Atmos. Chem. Phys., 25, 1145–1162, https://doi.org/10.5194/acp-25-1145-2025, https://doi.org/10.5194/acp-25-1145-2025, 2025
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Our results emphasise how understanding the geographical variation in surface types across the Antarctic is key to understanding secondary aerosol sources.
Adam E. Thomas, Hayley S. Glicker, Alex B. Guenther, Roger Seco, Oscar Vega Bustillos, Julio Tota, Rodrigo A. F. Souza, and James N. Smith
Atmos. Chem. Phys., 25, 959–977, https://doi.org/10.5194/acp-25-959-2025, https://doi.org/10.5194/acp-25-959-2025, 2025
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We present measurements of the organic composition of ultrafine particles collected from the eastern Amazon, an understudied region that is subjected to increasing human influence. We find that while isoprene chemistry is likely significant for ultrafine-particle growth throughout the year, compounds related to other sources, such as biological-spore emissions and biomass burning, exhibit striking seasonal differences, implying extensive variation in regional ultrafine-particle sources.
Xiufeng Lian, Yongjiang Xu, Fengxian Liu, Long Peng, Xiaodong Hu, Guigang Tang, Xu Dao, Hui Guo, Liwei Wang, Bo Huang, Chunlei Cheng, Lei Li, Guohua Zhang, Xinhui Bi, Xiaofei Wang, Zhen Zhou, and Mei Li
EGUsphere, https://doi.org/10.5194/egusphere-2024-3469, https://doi.org/10.5194/egusphere-2024-3469, 2025
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In this study, we analyzed the mixing state and atmospheric chemical processes of Pb-rich single particles in Beijing. Then, we focused on analyzing the differences in Pb-rich particles between the heating period and non-heating period, as well as the formation mechanism of lead nitrate after coal-to-gas conversion. Our results highlighted the improvement of coal-to-gas conversion on Pb in the particulate.
Chiara Giorio, Anne Monod, Valerio Di Marco, Pierre Herckes, Denise Napolitano, Amy Sullivan, Gautier Landrot, Daniel Warnes, Marika Nasti, Sara D'Aronco, Agathe Gérardin, Nicolas Brun, Karine Desboeufs, Sylvain Triquet, Servanne Chevaillier, Claudia Di Biagio, Francesco Battaglia, Frédéric Burnet, Stuart J. Piketh, Andreas Namwoonde, Jean-François Doussin, and Paola Formenti
EGUsphere, https://doi.org/10.5194/egusphere-2024-4140, https://doi.org/10.5194/egusphere-2024-4140, 2025
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A comparison between the solubility of trace metals in pairs of total suspended particulate (TSP) and fog water samples collected in Henties Bay, Namibia, during the AEROCLO-sA field campaign is presented. We found enhanced solubility of metals in fog samples which we attributed to metal-ligand complexes formation in the early stages of particle activation into droplets which can then remain in a kinetically stable form in fog or lead to the formation of colloidal nanoparticles.
Xu Yu, Min Zhou, Shuhui Zhu, Liping Qiao, Jinjian Li, Yingge Ma, Zijing Zhang, Kezheng Liao, Hongli Wang, and Jian Zhen Yu
EGUsphere, https://doi.org/10.5194/egusphere-2024-4103, https://doi.org/10.5194/egusphere-2024-4103, 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 first quantitative source analysis of ON aerosol and valuable observational evidence on secondary ON aerosol formation through NH3 and NOx chemistries.
Kumiko Goto-Azuma, Yoshimi Ogawa-Tsukagawa, Kaori Fukuda, Koji Fujita, Motohiro Hirabayashi, Remi Dallmayr, Jun Ogata, Nobuhiro Moteki, Tatsuhiro Mori, Sho Ohata, Yutaka Kondo, Makoto Koike, Sumito Matoba, Moe Kadota, Akane Tsushima, Naoko Nagatsuka, and Teruo Aoki
Atmos. Chem. Phys., 25, 657–683, https://doi.org/10.5194/acp-25-657-2025, https://doi.org/10.5194/acp-25-657-2025, 2025
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Monthly ice core records spanning 350 years from Greenland show trends in refractory black carbon (rBC) concentrations and sizes. rBC levels have increased since the 1870s due to the inflow of anthropogenic rBC, with larger diameters than those from biomass burning (BB) rBC. High summer BB rBC peaks may reduce the ice sheet albedo, but BB rBC showed no increase until the early 2000s. These results are vital for validating aerosol and climate models.
Petr Vodička, Kimitaka Kawamura, Bhagawati Kunwar, Lin Huang, Dhananjay K. Deshmukh, Md. Mozammel Haque, Sangeeta Sharma, and Leonard Barrie
EGUsphere, https://doi.org/10.5194/egusphere-2024-3656, https://doi.org/10.5194/egusphere-2024-3656, 2025
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Carbonate carbon (CC) is not negligible in Arctic total suspended particles (TSP). If not considered, CC biases the contribution of elemental and organic carbon. CC content in TSP was strongly reflected in the δ13C values of total carbon (TC). Carbon contribution from CaCO3 supports strong dependence of CC and δ13C on Ca. Finally, two hypothetical CC sources were identified based on the analysis of air mass back trajectories – dust resuspension and marine microorganisms.
Cited articles
Angle, K. J., Crocker, D. R., Simpson, R. M. C., Mayer, K. J., Garofalo, L. A., Moore, A. N., Garcia, S. L. M., Or, V. W., Srinivasan, S., Farhan, M., Sauer, J. S., Lee, C., Pothier, M. A., Farmer, D. K., Martz, T. R., Bertram, T. H., Cappa, C. D., Prather, K. A., and Grassian, V. H.: Acidity across the interface from the ocean surface to sea spray aerosol, P. Natl. Acad. Sci. USA, 118, e2018397118, https://doi.org/10.1073/pnas.2018397118, 2021.
Balasus, N., Battaglia Jr., M. A., Ball, K., Caicedo, V., Delgado, R., Carlton, A. G., and Hennigan, C. J.: Urban aerosol chemistry at a land–water transition site during summer – Part 1: Impact of agricultural and industrial ammonia emissions, Atmos. Chem. Phys., 21, 13051–13065, https://doi.org/10.5194/acp-21-13051-2021, 2021.
Battaglia Jr., M. A., Douglas, S., and Hennigan, C. J.: Effect of the Urban Heat Island on Aerosol pH, Environ. Sci. Technol., 51, 13095–13103, https://doi.org/10.1021/acs.est.7b02786, 2017.
Battaglia Jr., M. A., Weber, R. J., Nenes, A., and Hennigan, C. J.: Effects of water-soluble organic carbon on aerosol pH, Atmos. Chem. Phys., 19, 14607–14620, https://doi.org/10.5194/acp-19-14607-2019, 2019.
Bougiatioti, A., Nikolaou, P., Stavroulas, I., Kouvarakis, G., Weber, R., Nenes, A., Kanakidou, M., and Mihalopoulos, N.: Particle water and pH in the eastern Mediterranean: source variability and implications for nutrient availability, Atmos. Chem. Phys., 16, 4579–4591, https://doi.org/10.5194/acp-16-4579-2016, 2016.
Boyer, H. C., Gorkowski, K., and Sullivan, R. C.:
In Situ pH Measurements of Individual Levitated Microdroplets Using Aerosol Optical Tweezers,
Anal. Chem.,
92, 1089–1096, https://doi.org/10.1021/acs.analchem.9b04152, 2020.
Brimblecombe, P., and Clegg, S. L.:
The Solubility and Behavior of Acid Gases in the Marine Aerosol,
J. Atmos. Chem.,
7, 1–18, https://doi.org/10.1007/bf00048251, 1988.
Carlton, A. M. G., Pye, H. O. T., Baker, K. R., and Hennigan, C. J.: Additional benefits of federal air quality rules: model estimates of controllable biogenic secondary organic aerosol, Environ. Sci. Technol., 52, 9254–9265, https://doi.org/10.1021/acs.est.8b01869, 2018.
Craig, R. L., Peterson, P. K., Nandy, L., Lei, Z., Hossain, M. A., Camarena, S., Dodson, R. A., Cook, R. D., Dutcher, C. S., and Ault, A. P.:
Direct Determination of Aerosol pH: Size-Resolved Measurements of Submicrometer and Supermicrometer Aqueous Particles,
Anal. Chem.,
90, 11232–11239, https://doi.org/10.1021/acs.analchem.8b00586, 2018.
El-Sayed, M. M. H., Amenumey, D., and Hennigan, C. J.:
Drying-Induced Evaporation of Secondary Organic Aerosol during Summer,
Environ. Sci. Technol.,
50, 3626–3633, https://doi.org/10.1021/acs.est.5b06002, 2016.
Fang, T., Guo, H. Y., Zeng, L. H., Verma, V., Nenes, A., and Weber, R. J.:
Highly Acidic Ambient Particles, Soluble Metals, and Oxidative Potential: A Link between Sulfate and Aerosol Toxicity,
Environ. Sci. Technol.,
51, 2611–2620, https://doi.org/10.1021/acs.est.6b06151, 2017.
Feng, L., Shen, H., Zhu, Y., Gao, H., and Yao, X.:
Insight into Generation and Evolution of Sea-Salt Aerosols from Field Measurements in Diversified Marine and Coastal Atmospheres,
Sci. Rep.,
7, 41260, https://doi.org/10.1038/srep41260, 2017.
Fountoukis, C. and Nenes, A.: ISORROPIA II: a computationally efficient thermodynamic equilibrium model for K+-Ca2+-Mg2+-
Guo, H., Xu, L., Bougiatioti, A., Cerully, K. M., Capps, S. L., Hite Jr., J. R., Carlton, A. G., Lee, S.-H., Bergin, M. H., Ng, N. L., Nenes, A., and Weber, R. J.: Fine-particle water and pH in the southeastern United States, Atmos. Chem. Phys., 15, 5211–5228, https://doi.org/10.5194/acp-15-5211-2015, 2015.
Guo, H., Liu, J., Froyd, K. D., Roberts, J. M., Veres, P. R., Hayes, P. L., Jimenez, J. L., Nenes, A., and Weber, R. J.: Fine particle pH and gas–particle phase partitioning of inorganic species in Pasadena, California, during the 2010 CalNex campaign, Atmos. Chem. Phys., 17, 5703–5719, https://doi.org/10.5194/acp-17-5703-2017, 2017.
Guo, H., Nenes, A., and Weber, R. J.: The underappreciated role of nonvolatile cations in aerosol ammonium-sulfate molar ratios, Atmos. Chem. Phys., 18, 17307–17323, https://doi.org/10.5194/acp-18-17307-2018, 2018.
He, H., Stehr, J. W., Hains, J. C., Krask, D. J., Doddridge, B. G., Vinnikov, K. Y., Canty, T. P., Hosley, K. M., Salawitch, R. J., Worden, H. M., and Dickerson, R. R.: Trends in emissions and concentrations of air pollutants in the lower troposphere in the Baltimore/Washington airshed from 1997 to 2011, Atmos. Chem. Phys., 13, 7859–7874, https://doi.org/10.5194/acp-13-7859-2013, 2013.
Hennigan, C. J., Izumi, J., Sullivan, A. P., Weber, R. J., and Nenes, A.: A critical evaluation of proxy methods used to estimate the acidity of atmospheric particles, Atmos. Chem. Phys., 15, 2775–2790, https://doi.org/10.5194/acp-15-2775-2015, 2015.
Jang, M., Sun, S., Winslow, R., Han, S., and Yu, Z.:
In situ aerosol acidity measurements using a UV–Visible micro-spectrometer and its application to the ambient air,
Aerosol Sci. Tech.,
54, 446–461, https://doi.org/10.1080/02786826.2020.1711510, 2020.
Kakavas, S., Patoulias, D., Zakoura, M., Nenes, A., and Pandis, S. N.: Size-resolved aerosol pH over Europe during summer, Atmos. Chem. Phys., 21, 799–811, https://doi.org/10.5194/acp-21-799-2021, 2021.
Kanakidou, M., Myriokefalitakis, S., Daskalakis, N., Fanourgakis, G., Nenes, A., Baker, A. R., Tsigaridis, K., and Mihalopoulos, N.:
Past, Present, and Future Atmospheric Nitrogen Deposition,
J. Atmos. Sci.,
73, 2039–2047, https://doi.org/10.1175/jas-d-15-0278.1, 2016.
Keene, W. C., Pszenny, A. A. P., Maben, J. R., and Sander, R.:
Variation of marine aerosol acidity with particle size,
Geophys. Res. Lett.,
29, 1101, https://doi.org/10.1029/2001gl013881, 2002.
Keene, W. C., Pszenny, A. A. P., Maben, J. R., Stevenson, E., and Wall, A.:
Closure evaluation of size-resolved aerosol pH in the New England coastal atmosphere during summer,
J. Geophys. Res.-Atmos.,
109, D23307, https://doi.org/10.1029/2004jd004801, 2004.
Loughner, C. P., Tzortziou, M., Follette-Cook, M., Pickering, K. E., Goldberg, D., Satam, C., Weinheimer, A., Crawford, J. H., Knapp, D. J., Montzka, D. D., Diskin, G. S., and Dickerson, R. R.:
Impact of Bay-Breeze Circulations on Surface Air Quality and Boundary Layer Export,
J. Appl. Meteorol. Clim.,
53, 1697–1713, https://doi.org/10.1175/jamc-d-13-0323.1, 2014.
Loughner, C. P., Tzortziou, M., Shroder, S., and Pickering, K. E.:
Enhanced dry deposition of nitrogen pollution near coastlines: A case study covering the Chesapeake Bay estuary and Atlantic Ocean coastline,
J. Geophys. Res.-Atmos.,
121, 14221–14238, https://doi.org/10.1002/2016jd025571, 2016.
Murphy, J. G., Gregoire, P., Tevlin, A., Wentworth, G., Ellis, R., Markovic, M., and VandenBoer, T.: Observational constraints on particle acidity using measurements and modelling of particles and gases, Faraday Discuss., 200, 379–395, https://doi.org/10.1039/C7FD00086C, 2017.
NASA: Airborne Science Data for Atmospheric Composition, available at: https://www-air.larc.nasa.gov/cgi-bin/ArcView/owlets.2018, last access: 14 December 2021.
Nenes, A., Pandis, S. N., Weber, R. J., and Russell, A.: Aerosol pH and liquid water content determine when particulate matter is sensitive to ammonia and nitrate availability, Atmos. Chem. Phys., 20, 3249–3258, https://doi.org/10.5194/acp-20-3249-2020, 2020.
Nenes, A., Pandis, S. N., Kanakidou, M., Russell, A. G., Song, S., Vasilakos, P., and Weber, R. J.: Aerosol acidity and liquid water content regulate the dry deposition of inorganic reactive nitrogen, Atmos. Chem. Phys., 21, 6023–6033, https://doi.org/10.5194/acp-21-6023-2021, 2021.
Norman, M., Spirig, C., Wolff, V., Trebs, I., Flechard, C., Wisthaler, A., Schnitzhofer, R., Hansel, A., and Neftel, A.: Intercomparison of ammonia measurement techniques at an intensively managed grassland site (Oensingen, Switzerland), Atmos. Chem. Phys., 9, 2635–2645, https://doi.org/10.5194/acp-9-2635-2009, 2009.
O'Dowd, C. D., and De Leeuw, G.:
Marine aerosol production: a review of the current knowledge,
Philos. T. R. Soc. A,
365, 1753–1774, https://doi.org/10.1098/rsta.2007.2043, 2007.
Phillips, S. M., Bellcross, A. D., and Smith, G. D.: Light Absorption by Brown Carbon in the Southeastern United States is pH-dependent, Environ. Sci. Technol., 51, 6782–6790, https://doi.org/10.1021/acs.est.7b01116, 2017.
Pinder, R. W., Adams, P. J., Pandis, S. N., and Gilliland, A. B.:
Temporally resolved ammonia emission inventories: Current estimates, evaluation tools, and measurement needs,
J. Geophys. Res.-Atmos.,
111, D16310, https://doi.org/10.1029/2005jd006603, 2006.
Pritchard, D. W.:
Salinity Distribution and Circulation in the Chesapeake Bay Estuarine System,
J. Mar. Res.,
11, 106–123, 1952.
Pszenny, A. A. P., Moldanová, J., Keene, W. C., Sander, R., Maben, J. R., Martinez, M., Crutzen, P. J., Perner, D., and Prinn, R. G.: Halogen cycling and aerosol pH in the Hawaiian marine boundary layer, Atmos. Chem. Phys., 4, 147–168, https://doi.org/10.5194/acp-4-147-2004, 2004.
Pye, H. O. T., Zuend, A., Fry, J. L., Isaacman-VanWertz, G., Capps, S. L., Appel, K. W., Foroutan, H., Xu, L., Ng, N. L., and Goldstein, A. H.: Coupling of organic and inorganic aerosol systems and the effect on gas–particle partitioning in the southeastern US, Atmos. Chem. Phys., 18, 357–370, https://doi.org/10.5194/acp-18-357-2018, 2018.
Pye, H. O. T., Nenes, A., Alexander, B., Ault, A. P., Barth, M. C., Clegg, S. L., Collett Jr., J. L., Fahey, K. M., Hennigan, C. J., Herrmann, H., Kanakidou, M., Kelly, J. T., Ku, I.-T., McNeill, V. F., Riemer, N., Schaefer, T., Shi, G., Tilgner, A., Walker, J. T., Wang, T., Weber, R., Xing, J., Zaveri, R. A., and Zuend, A.: The acidity of atmospheric particles and clouds, Atmos. Chem. Phys., 20, 4809–4888, https://doi.org/10.5194/acp-20-4809-2020, 2020.
Rindelaub, J. D., Craig, R. L., Nandy, L., Bondy, A. L., Dutcher, C. S., Shepson, P. B., and Ault, A. P.:
Direct Measurement of pH in Individual Particles via Raman Microspectroscopy and Variation in Acidity with Relative Humidity,
J. Phys. Chem. A,
120, 911–917, https://doi.org/10.1021/acs.jpca.5b12699, 2016.
Seinfeld, J. H., and Pandis, S. N.: Atmospheric chemistry and physics: from air pollution to climate change, 3rd Edn., John Wiley and Sons, Hoboken, NJ, 2016.
Tao, Y.: Identification of Major Factors Influencing Aerosol pH and the Quantitative Relationship between pH and Ammonia Gas/Particle Partitioning, PhD Thesis, University of Toronto, Toronto, available at: https://hdl.handle.net/1807/103788 (last access: 30 April 2021), 2020.
Tao, Y. and Murphy, J. G.: The sensitivity of PM2.5 acidity to meteorological parameters and chemical composition changes: 10-year records from six Canadian monitoring sites, Atmos. Chem. Phys., 19, 9309–9320, https://doi.org/10.5194/acp-19-9309-2019, 2019.
Valerino, M. J., Johnson, J. J., Izumi, J., Orozco, D., Hoff, R. M., Delgado, R., and Hennigan, C. J.:
Sources and composition of PM2.5 in the Colorado Front Range during the DISCOVER-AQ study,
J. Geophys. Res.-Atmos.,
122, 566–582, https://doi.org/10.1002/2016jd025830, 2017.
Vasilakos, P., Russell, A., Weber, R., and Nenes, A.: Understanding nitrate formation in a world with less sulfate, Atmos. Chem. Phys., 18, 12765–12775, https://doi.org/10.5194/acp-18-12765-2018, 2018.
Weber, R. J., Guo, H., Russell, A. G., and Nenes, A.:
High aerosol acidity despite declining atmospheric sulfate concentrations over the past 15 years,
Nat. Geosci.,
9, 282–285, https://doi.org/10.1038/ngeo2665, 2016.
Zheng, G., Su, H., Wang, S., Andreae, M. O., Pöschl, U., and Cheng, Y.:
Multiphase buffer theory explains contrasts in atmospheric aerosol acidity,
Science,
369, 1374, https://doi.org/10.1126/science.aba3719, 2020.
Short summary
This study characterizes aerosol liquid water content and aerosol pH at a land–water transition site near Baltimore, Maryland. We characterize the effects of unique meteorology associated with the close proximity to the Chesapeake Bay and episodic NH3 events derived from industrial and agricultural sources on aerosol chemistry during the summer. We also examine two events where primary Bay emissions underwent aging in the polluted urban atmosphere.
This study characterizes aerosol liquid water content and aerosol pH at a land–water transition...
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