Articles | Volume 13, issue 20
https://doi.org/10.5194/acp-13-10203-2013
© Author(s) 2013. 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-13-10203-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
17 Oct 2013
Research article |
| 17 Oct 2013
Particle partitioning potential of organic compounds is highest in the Eastern US and driven by anthropogenic water
A. G. Carlton
Dept. of Environmental Sciences, Rutgers University, New Brunswick, NJ 08901, USA
B. J. Turpin
Dept. of Environmental Sciences, Rutgers University, New Brunswick, NJ 08901, USA
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This research investigates how air quality, specifically NO2 concentrations, is different under clear and cloudy skies. We find that in situ surface NO2 is, on average, +36 % larger during cloudy days versus clear sky days, with a wide distribution based on geographic region and roadway proximity: largest in the Northeast U.S. and smallest in the Southwest U.S. and near major roadways. This has implications for satellite data applications, which only use measurements in the absence of clouds.
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The Fire INventory from NCAR (FINN) provides daily global estimates of emissions from open fires based on satellite detections of hot spots. This version has been updated to apply MODIS and VIIRS satellite fire detection and better represents both large and small fires. FINNv2.5 generates more emissions than FINNv1 and is in general agreement with other fire emissions inventories. The new estimates are consistent with satellite observations, but uncertainties remain regionally and by pollutant.
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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.
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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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Much of what we know about atmospheric new particle formation (NPF) is based on ground-level measurements. We used tethered balloon measurements and remote sensing to study the location in the boundary layer in which NPF events are initiated, the degree to which the boundary layer is well-mixed during NPF, and the potential role that water may play in aerosol particle chemical evolution. This information will improve the representativeness of process level models and laboratory experiments.
Benjamin N. Murphy, Matthew C. Woody, Jose L. Jimenez, Ann Marie G. Carlton, Patrick L. Hayes, Shang Liu, Nga L. Ng, Lynn M. Russell, Ari Setyan, Lu Xu, Jeff Young, Rahul A. Zaveri, Qi Zhang, and Havala O. T. Pye
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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.
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
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(2) The SOA formed only from the oxidation of VOCs is insufficient to explain the observed SOA concentrations.
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(4) Modeled SOA depends strongly on the P-S/IVOC volatility distribution.
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This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
This research investigates how air quality, specifically NO2 concentrations, is different under clear and cloudy skies. We find that in situ surface NO2 is, on average, +36 % larger during cloudy days versus clear sky days, with a wide distribution based on geographic region and roadway proximity: largest in the Northeast U.S. and smallest in the Southwest U.S. and near major roadways. This has implications for satellite data applications, which only use measurements in the absence of clouds.
Christine Wiedinmyer, Yosuke Kimura, Elena C. McDonald-Buller, Louisa K. Emmons, Rebecca R. Buchholz, Wenfu Tang, Keenan Seto, Maxwell B. Joseph, Kelley C. Barsanti, Annmarie G. Carlton, and Robert Yokelson
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The Fire INventory from NCAR (FINN) provides daily global estimates of emissions from open fires based on satellite detections of hot spots. This version has been updated to apply MODIS and VIIRS satellite fire detection and better represents both large and small fires. FINNv2.5 generates more emissions than FINNv1 and is in general agreement with other fire emissions inventories. The new estimates are consistent with satellite observations, but uncertainties remain regionally and by pollutant.
Michael A. Battaglia Jr., Nicholas Balasus, Katherine Ball, Vanessa Caicedo, Ruben Delgado, Annmarie G. Carlton, and Christopher J. Hennigan
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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.
Nicholas Balasus, Michael A. Battaglia Jr., Katherine Ball, Vanessa Caicedo, Ruben Delgado, Annmarie G. Carlton, and Christopher J. Hennigan
Atmos. Chem. Phys., 21, 13051–13065, https://doi.org/10.5194/acp-21-13051-2021, https://doi.org/10.5194/acp-21-13051-2021, 2021
Short summary
Short summary
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.
Amy E. Christiansen, Annmarie G. Carlton, and Barron H. Henderson
Atmos. Chem. Phys., 20, 11607–11624, https://doi.org/10.5194/acp-20-11607-2020, https://doi.org/10.5194/acp-20-11607-2020, 2020
Short summary
Short summary
We quantify differences in surface-level fine particle mass (PM2.5) chemical composition in relation to satellite-derived cloud flags and find significant differences between clear-sky and cloud days. The work suggests that future analysis in this area is warranted.
Hayley S. Glicker, Michael J. Lawler, John Ortega, Suzane S. de Sá, Scot T. Martin, Paulo Artaxo, Oscar Vega Bustillos, Rodrigo de Souza, Julio Tota, Annmarie Carlton, and James N. Smith
Atmos. Chem. Phys., 19, 13053–13066, https://doi.org/10.5194/acp-19-13053-2019, https://doi.org/10.5194/acp-19-13053-2019, 2019
Short summary
Short summary
An understanding of the chemical composition of the smallest particles in the air over the Amazon Basin provides insights into the natural and human-caused influences on particle production in this sensitive region. We present measurements of the composition of sub-100 nm diameter particles performed during the wet season and identify unique constituents that point to both natural and human-caused sources and processes.
Yong Bin Lim, Jihoon Seo, Jin Young Kim, and Barbara J. Turpin
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-364, https://doi.org/10.5194/acp-2018-364, 2018
Revised manuscript not accepted
Short summary
Short summary
Currently high concentration PM formation in East Asia (China and Korea) is poorly understood. Furthermore, the combination of the transport from China and the local formation complicates PM formation in Korea. Based on our field and smog chamber studies, water in particles plays an important role. Transported wet particles take up HNO3 at Seoul characterized by high NOx/RH and photochemistry. Accumulated nitrates take up water and facilitate aqueous chemistry leading to secondary formation.
Jingqiu Mao, Annmarie Carlton, Ronald C. Cohen, William H. Brune, Steven S. Brown, Glenn M. Wolfe, Jose L. Jimenez, Havala O. T. Pye, Nga Lee Ng, Lu Xu, V. Faye McNeill, Kostas Tsigaridis, Brian C. McDonald, Carsten Warneke, Alex Guenther, Matthew J. Alvarado, Joost de Gouw, Loretta J. Mickley, Eric M. Leibensperger, Rohit Mathur, Christopher G. Nolte, Robert W. Portmann, Nadine Unger, Mika Tosca, and Larry W. Horowitz
Atmos. Chem. Phys., 18, 2615–2651, https://doi.org/10.5194/acp-18-2615-2018, https://doi.org/10.5194/acp-18-2615-2018, 2018
Short summary
Short summary
This paper is aimed at discussing progress in evaluating, diagnosing, and improving air quality and climate modeling using comparisons to SAS observations as a guide to thinking about improvements to mechanisms and parameterizations in models.
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
Atmos. Chem. Phys., 18, 311–326, https://doi.org/10.5194/acp-18-311-2018, https://doi.org/10.5194/acp-18-311-2018, 2018
Short summary
Short summary
Much of what we know about atmospheric new particle formation (NPF) is based on ground-level measurements. We used tethered balloon measurements and remote sensing to study the location in the boundary layer in which NPF events are initiated, the degree to which the boundary layer is well-mixed during NPF, and the potential role that water may play in aerosol particle chemical evolution. This information will improve the representativeness of process level models and laboratory experiments.
Benjamin N. Murphy, Matthew C. Woody, Jose L. Jimenez, Ann Marie G. Carlton, Patrick L. Hayes, Shang Liu, Nga L. Ng, Lynn M. Russell, Ari Setyan, Lu Xu, Jeff Young, Rahul A. Zaveri, Qi Zhang, and Havala O. T. Pye
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
Short summary
Short summary
We incorporate recent findings about the behavior of organic pollutants in urban airsheds into the Community Multiscale Air Quality (CMAQ) model to refine predictions of organic particulate pollution in the United States. The new techniques, which account for the volatility and ongoing chemistry of airborne organic compounds, substantially reduce biases, particularly in the winter time and near emission sources.
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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Short summary
Short summary
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.
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
Short summary
Short summary
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
Yong Bin Lim, Hwajin Kim, Jin Young Kim, and Barbara J. Turpin
Atmos. Chem. Phys., 16, 12631–12647, https://doi.org/10.5194/acp-16-12631-2016, https://doi.org/10.5194/acp-16-12631-2016, 2016
Short summary
Short summary
We report that organonitrates were photochemically formed in wet aerosols via aqueous chemistry in the NOx–O3 chamber at high humidity. Organonitrates are considered to form in the gas phase (peroxy radical–NO during the daytime or VOC–NO3 during the nighttime); however, our chamber study results suggest daytime organonitrate formation in polluted and humid areas. Besides organonitrates, organonitrogens, organosulfates, and organonitrogen sulfates were also dominant photooxidation products.
Silvia Sandrini, Dominik van Pinxteren, Lara Giulianelli, Hartmut Herrmann, Laurent Poulain, Maria Cristina Facchini, Stefania Gilardoni, Matteo Rinaldi, Marco Paglione, Barbara J. Turpin, Francesca Pollini, Silvia Bucci, Nicola Zanca, and Stefano Decesari
Atmos. Chem. Phys., 16, 10879–10897, https://doi.org/10.5194/acp-16-10879-2016, https://doi.org/10.5194/acp-16-10879-2016, 2016
Short summary
Short summary
This paper deals with impactor measurements performed in the summer 2012 during the EU project PEGASOS campaign in the Po Valley, at an urban and a rural site. The paper tries to disentangle the effects of weather anomalies (temporal and spatial) from those of diverse emissions (NH3) and chemical processes on the formation of secondary aerosols in the region, with special focus on nocturnal ammonium nitrate formation and its implications (aqueous formation of secondary organic aerosol).
Amy P. Sullivan, Natasha Hodas, Barbara J. Turpin, Kate Skog, Frank N. Keutsch, Stefania Gilardoni, Marco Paglione, Matteo Rinaldi, Stefano Decesari, Maria Cristina Facchini, Laurent Poulain, Hartmut Herrmann, Alfred Wiedensohler, Eiko Nemitz, Marsailidh M. Twigg, and Jeffrey L. Collett Jr.
Atmos. Chem. Phys., 16, 8095–8108, https://doi.org/10.5194/acp-16-8095-2016, https://doi.org/10.5194/acp-16-8095-2016, 2016
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This paper presents the results from our measurements and approach for the investigation of aqueous secondary organic aerosol (aqSOA) formation in the ambient atmosphere. When local aqSOA formation was observed, a correlation of water-soluble organic carbon with organic aerosol, aerosol liquid water, relative humidity, and aerosol nitrate was found. Key factors of local aqSOA production include air mass stagnation, formation of local nitrate overnight, and significant amounts of ammonia.
Y. B. Lim and B. J. Turpin
Atmos. Chem. Phys., 15, 12867–12877, https://doi.org/10.5194/acp-15-12867-2015, https://doi.org/10.5194/acp-15-12867-2015, 2015
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This paper demonstrates organic peroxide and peroxyhemiacetal formation during aqueous photooxidation of methylglyoxal using ultra-high-resolution Fourier transform ion cyclotron resonance electrospray ionization mass spectrometry (FTICR-MS). Then, we provide simulation results of organic peroxide/peroxyhemiacetal formation in clouds and wet aerosols and discuss organic peroxides as a source of condensed-phase OH radicals and as a contributor to aqueous secondary organic aerosol (SOA).
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
Short summary
Short summary
(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.
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
Y. B. Lim, Y. Tan, and B. J. Turpin
Atmos. Chem. Phys., 13, 8651–8667, https://doi.org/10.5194/acp-13-8651-2013, https://doi.org/10.5194/acp-13-8651-2013, 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: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
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Cluster-dynamics-based parameterization for sulfuric acid–dimethylamine nucleation: comparison and selection through box and three-dimensional modeling
A Comprehensive Global Modelling Assessment of Nitrate Heterogeneous Formation on Desert Dust
Modelling of atmospheric variability of gas and aerosols during the ACROSS campaign 2022 in the greater Paris area: evaluation of the meteorology, dynamics and chemistry
Observed and CMIP6-model-simulated organic aerosol response to drought in the contiguous United States during summertime
Cooling radiative forcing effect enhancement of atmospheric amines and mineral particles caused by heterogeneous uptake and oxidation
Source-resolved atmospheric metal emissions, concentrations, and deposition fluxes into the East Asian seas
Analysis of secondary inorganic aerosols over the greater Athens area using the EPISODE–CityChem source dispersion and photochemistry model
Global estimates of ambient reactive nitrogen components during 2000–2100 based on the multi-stage model
The role of naphthalene and its derivatives in the formation of secondary organic aerosol in the Yangtze River Delta region, China
Unveiling the optimal regression model for source apportionment of the oxidative potential of PM10
Investigating the contribution of grown new particles to cloud condensation nuclei with largely varying preexisting particles – Part 2: Modeling chemical drivers and 3-D new particle formation occurrence
Technical note: Influence of different averaging metrics and temporal resolutions on the aerosol pH calculated by thermodynamic modeling
Dual roles of the inorganic aqueous phase on secondary organic aerosol growth from benzene and phenol
Global source apportionment of aerosols into major emission regions and sectors over 1850–2017
Modeling atmospheric brown carbon in the GISS ModelE Earth system model
Observation-constrained kinetic modeling of isoprene SOA formation in the atmosphere
Significant impact of urban tree biogenic emissions on air quality estimated by a bottom-up inventory and chemistry transport modeling
Secondary organic aerosols derived from intermediate-volatility n-alkanes adopt low-viscous phase state
Spatial-temporal patterns of anthropogenic and biomass burning contributions on air pollution and mortality burden changes in India from 1995 to 2014
Modeling the drivers of fine PM pollution over Central Europe: impacts and contributions of emissions from different sources
Reaction of SO3 with H2SO4 and its implications for aerosol particle formation in the gas phase and at the air–water interface
Weakened aerosol–radiation interaction exacerbating ozone pollution in eastern China since China's clean air actions
Uncertainties from biomass burning aerosols in air quality models obscure public health impacts in Southeast Asia
Oxidative potential apportionment of atmospheric PM1: a new approach combining high-sensitive online analysers for chemical composition and offline OP measurement technique
Natalie M. Mahowald, Longlei Li, Julius Vira, Marje Prank, Douglas S. Hamilton, Hitoshi Matsui, Ron L. Miller, P. Louis Lu, Ezgi Akyuz, Daphne Meidan, Peter Hess, Heikki Lihavainen, Christine Wiedinmyer, Jenny Hand, Maria Grazia Alaimo, Célia Alves, Andres Alastuey, Paulo Artaxo, Africa Barreto, Francisco Barraza, Silvia Becagli, Giulia Calzolai, Shankararaman Chellam, Ying Chen, Patrick Chuang, David D. Cohen, Cristina Colombi, Evangelia Diapouli, Gaetano Dongarra, Konstantinos Eleftheriadis, Johann Engelbrecht, Corinne Galy-Lacaux, Cassandra Gaston, Dario Gomez, Yenny González Ramos, Roy M. Harrison, Chris Heyes, Barak Herut, Philip Hopke, Christoph Hüglin, Maria Kanakidou, Zsofia Kertesz, Zbigniew Klimont, Katriina Kyllönen, Fabrice Lambert, Xiaohong Liu, Remi Losno, Franco Lucarelli, Willy Maenhaut, Beatrice Marticorena, Randall V. Martin, Nikolaos Mihalopoulos, Yasser Morera-Gómez, Adina Paytan, Joseph Prospero, Sergio Rodríguez, Patricia Smichowski, Daniela Varrica, Brenna Walsh, Crystal L. Weagle, and Xi Zhao
Atmos. Chem. Phys., 25, 4665–4702, https://doi.org/10.5194/acp-25-4665-2025, https://doi.org/10.5194/acp-25-4665-2025, 2025
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Aerosol particles are an important part of the Earth system, but their concentrations are spatially and temporally heterogeneous, as well as being variable in size and composition. Here, we present a new compilation of PM2.5 and PM10 aerosol observations, focusing on the spatial variability across different observational stations, including composition, and demonstrate a method for comparing the data sets to model output.
Zhenyu Zhang, Jing Li, Huizheng Che, Yueming Dong, Oleg Dubovik, Thomas Eck, Pawan Gupta, Brent Holben, Jhoon Kim, Elena Lind, Trailokya Saud, Sachchida Nand Tripathi, and Tong Ying
Atmos. Chem. Phys., 25, 4617–4637, https://doi.org/10.5194/acp-25-4617-2025, https://doi.org/10.5194/acp-25-4617-2025, 2025
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We used ground-based remote sensing data from the Aerosol Robotic Network to examine long-term trends in aerosol characteristics. We found aerosol loadings generally decreased globally, and aerosols became more scattering. These changes are closely related to variations in aerosol compositions, such as decreased anthropogenic emissions over East Asia, Europe, and North America; increased anthropogenic sources over northern India; and increased dust activity over the Arabian Peninsula.
Erin J. Emme and Hannah M. Horowitz
Atmos. Chem. Phys., 25, 4531–4545, https://doi.org/10.5194/acp-25-4531-2025, https://doi.org/10.5194/acp-25-4531-2025, 2025
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There is uncertainty in the sources of Arctic cold-season (November–April) sea salt aerosols. Using a chemical transport model and satellite observations, we quantify Arctic-wide sea salt aerosol emissions from fractures in sea ice, called open sea ice leads, and their atmospheric chemistry impacts for the cold season. We show that sea ice leads contribute to Arctic sea salt aerosols and bromine, especially in under-observed regions.
Ursula A. Jongebloed, Jacob I. Chalif, Linia Tashmim, William C. Porter, Kelvin H. Bates, Qianjie Chen, Erich C. Osterberg, Bess G. Koffman, Jihong Cole-Dai, Dominic A. Winski, David G. Ferris, Karl J. Kreutz, Cameron P. Wake, and Becky Alexander
Atmos. Chem. Phys., 25, 4083–4106, https://doi.org/10.5194/acp-25-4083-2025, https://doi.org/10.5194/acp-25-4083-2025, 2025
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Marine phytoplankton emit dimethyl sulfide (DMS), which forms methanesulfonic acid (MSA) and sulfate. MSA concentrations in ice cores decreased over the industrial era, which has been attributed to pollution-driven changes in DMS chemistry. We use a model to investigate DMS chemistry compared to observations of DMS, MSA, and sulfate. We find that modeled DMS, MSA, and sulfate are influenced by pollution-sensitive oxidant concentrations, characterization of DMS chemistry, and other variables.
Xiaolin Duan, Guangjie Zheng, Chuchu Chen, Qiang Zhang, and Kebin He
Atmos. Chem. Phys., 25, 3919–3928, https://doi.org/10.5194/acp-25-3919-2025, https://doi.org/10.5194/acp-25-3919-2025, 2025
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Aerosol acidity is an important parameter in atmospheric chemistry, while its driving factors, especially chemical profiles versus meteorological conditions, are not yet fully understood. Here, we established a hierarchical quantitative analysis framework to understand the driving factors of aerosol acidity on different timescales. Its application in Changzhou, China, revealed distinct driving factors and corresponding mechanisms of aerosol acidity from annual trends to random residuals.
Wenxin Zhang, Yaman Liu, Man Yue, Xinyi Dong, Kan Huang, and Minghuai Wang
Atmos. Chem. Phys., 25, 3857–3872, https://doi.org/10.5194/acp-25-3857-2025, https://doi.org/10.5194/acp-25-3857-2025, 2025
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Understanding long-term organic aerosol (OA) trends and their driving factors is important for air quality management. Our modeling revealed that OA in China increased by 5.6 % from 1990 to 2019, primarily due to a 32.3 % increase in secondary organic aerosols (SOAs) and an 8.1 % decrease in primary organic aerosols (POAs), both largely driven by changes in anthropogenic emissions. Biogenic SOA increased due to warming but showed little response to changes in anthropogenic nitrogen oxide emissions.
Soo-Jin Park, Lya Lugon, Oscar Jacquot, Youngseob Kim, Alexia Baudic, Barbara D'Anna, Ludovico Di Antonio, Claudia Di Biagio, Fabrice Dugay, Olivier Favez, Véronique Ghersi, Aline Gratien, Julien Kammer, Jean-Eudes Petit, Olivier Sanchez, Myrto Valari, Jérémy Vigneron, and Karine Sartelet
Atmos. Chem. Phys., 25, 3363–3387, https://doi.org/10.5194/acp-25-3363-2025, https://doi.org/10.5194/acp-25-3363-2025, 2025
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To accurately represent the population exposure to outdoor concentrations of pollutants of interest to health (NO2, PM2.5, black carbon, and ultrafine particles), multi-scale modelling down to the street scale is set up and evaluated using measurements from field campaigns. An exposure scaling factor is defined, allowing regional-scale simulations to be corrected to evaluate population exposure. Urban heterogeneities strongly influence NO2, black carbon, and ultrafine particles but less strongly PM2.5.
Sara L. Farrell, Havala O. T. Pye, Robert Gilliam, George Pouliot, Deanna Huff, Golam Sarwar, William Vizuete, Nicole Briggs, Fengkui Duan, Tao Ma, Shuping Zhang, and Kathleen Fahey
Atmos. Chem. Phys., 25, 3287–3312, https://doi.org/10.5194/acp-25-3287-2025, https://doi.org/10.5194/acp-25-3287-2025, 2025
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In this work we implement heterogeneous sulfur chemistry into the Community Multiscale Air Quality (CMAQ) model. This new chemistry accounts for the formation of sulfate via aqueous oxidation of SO2 in aerosol liquid water and the formation of hydroxymethanesulfonate (HMS) – often confused by measurement techniques as sulfate. Model performance in predicting sulfur PM2.5 in Fairbanks, Alaska, and other places that experience dark and cold winters is improved.
Paul A. Makar, Philip Cheung, Christian Hogrefe, Ayodeji Akingunola, Ummugulsum Alyuz, Jesse O. Bash, Michael D. Bell, Roberto Bellasio, Roberto Bianconi, Tim Butler, Hazel Cathcart, Olivia E. Clifton, Alma Hodzic, Ioannis Kioutsioukis, Richard Kranenburg, Aurelia Lupascu, Jason A. Lynch, Kester Momoh, Juan L. Perez-Camanyo, Jonathan Pleim, Young-Hee Ryu, Roberto San Jose, Donna Schwede, Thomas Scheuschner, Mark W. Shephard, Ranjeet S. Sokhi, and Stefano Galmarini
Atmos. Chem. Phys., 25, 3049–3107, https://doi.org/10.5194/acp-25-3049-2025, https://doi.org/10.5194/acp-25-3049-2025, 2025
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The large range of sulfur and nitrogen deposition estimates from air quality models results in a large range of predicted impacts. We used models and deposition diagnostics to identify the processes controlling atmospheric sulfur and nitrogen deposition variability. Controlling factors included the uptake of gases and aerosols by hydrometeors, aerosol inorganic chemistry, particle dry deposition, ammonia bidirectional fluxes, gas deposition via plant cuticles and soil, and land use data.
Lang Liu, Xin Long, Yi Li, Zengliang Zang, Fengwen Wang, Yan Han, Zhier Bao, Yang Chen, Tian Feng, and Jinxin Yang
Atmos. Chem. Phys., 25, 1569–1585, https://doi.org/10.5194/acp-25-1569-2025, https://doi.org/10.5194/acp-25-1569-2025, 2025
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This study uses WRF-Chem to assess how meteorological conditions and emission reductions affected fine particulate matter (PM2.5) in the North China Plain (NCP). It highlights regional disparities: in the northern NCP, adverse weather negated emission reduction effects. In contrast, the southern NCP featured a PM2.5 decrease due to favorable weather and emission reductions. The research highlighted the interaction between emissions, meteorology, and PM2.5.
Alexandros Milousis, Klaus Klingmüller, Alexandra P. Tsimpidi, Jasper F. Kok, Maria Kanakidou, Athanasios Nenes, and Vlassis A. Karydis
Atmos. Chem. Phys., 25, 1333–1351, https://doi.org/10.5194/acp-25-1333-2025, https://doi.org/10.5194/acp-25-1333-2025, 2025
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This study investigates the impact of dust on the global radiative effect of nitrate aerosols. The results indicate both positive and negative regional shortwave and longwave radiative effects due to aerosol–radiation interactions and cloud adjustments. The global average net REari and REaci of nitrate aerosols are −0.11 and +0.17 W m−2, respectively, mainly affecting the shortwave spectrum. Sensitivity simulations evaluated the influence of mineral dust composition and emissions on the results.
Judith Kleinheins, Nadia Shardt, Ulrike Lohmann, and Claudia Marcolli
Atmos. Chem. Phys., 25, 881–903, https://doi.org/10.5194/acp-25-881-2025, https://doi.org/10.5194/acp-25-881-2025, 2025
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We model the cloud condensation nuclei (CCN) activation of sea spray aerosol particles with classical Köhler theory and with a new model approach that takes surface tension lowering into account. We categorize organic compounds into weak, intermediate, and strong surfactants, and we outline for which composition surface tension lowering is important. The results suggest that surface tension lowering allows sea spray aerosol particles in the Aitken mode to be a source of CCN in marine updraughts.
Olivia G. Norman, Colette L. Heald, Solomon Bililign, Pedro Campuzano-Jost, Hugh Coe, Marc N. Fiddler, Jaime R. Green, Jose L. Jimenez, Katharina Kaiser, Jin Liao, Ann M. Middlebrook, Benjamin A. Nault, John B. Nowak, Johannes Schneider, and André Welti
Atmos. Chem. Phys., 25, 771–795, https://doi.org/10.5194/acp-25-771-2025, https://doi.org/10.5194/acp-25-771-2025, 2025
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This study finds that one component of secondary inorganic aerosols, nitrate, is greatly overestimated by a global atmospheric chemistry model compared to observations from 11 flight campaigns. None of the loss and production pathways explored can explain the nitrate bias alone. The model’s inability to capture the variability in the observations remains and requires future investigation to avoid biases in policy-related studies (i.e., air quality, health, climate impacts of these aerosols).
Ryan Vella, Matthew Forrest, Andrea Pozzer, Alexandra P. Tsimpidi, Thomas Hickler, Jos Lelieveld, and Holger Tost
Atmos. Chem. Phys., 25, 243–262, https://doi.org/10.5194/acp-25-243-2025, https://doi.org/10.5194/acp-25-243-2025, 2025
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This study examines how land cover changes influence biogenic volatile organic compound (BVOC) emissions and atmospheric states. Using a coupled chemistry–climate–vegetation model, we compare present-day land cover (deforested for crops and grazing) with natural vegetation and an extreme reforestation scenario. We find that vegetation changes significantly impact global BVOC emissions and organic aerosols but have a relatively small effect on total aerosols, clouds, and radiative effects.
Mashiat Hossain, Rebecca M. Garland, and Hannah M. Horowitz
Atmos. Chem. Phys., 24, 14123–14143, https://doi.org/10.5194/acp-24-14123-2024, https://doi.org/10.5194/acp-24-14123-2024, 2024
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Our research examines aerosol dynamics over the southeast Atlantic, a region with significant uncertainties in aerosol radiative forcings. Using the GEOS-Chem model, we find that at cloud altitudes, organic aerosols dominate during the biomass burning season, while sulfate aerosols, driven by marine emissions, prevail during peak primary production. These findings highlight the need for accurate representation of marine aerosols in models to improve climate predictions and reduce uncertainties.
Ashok K. Luhar, Anthony C. Jones, and Jonathan M. Wilkinson
Atmos. Chem. Phys., 24, 14005–14028, https://doi.org/10.5194/acp-24-14005-2024, https://doi.org/10.5194/acp-24-14005-2024, 2024
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Nitrate aerosol is often omitted in global chemistry–climate models, partly due to the chemical complexity of its formation process. Using a global model, we show that including nitrate aerosol significantly impacts tropospheric composition fields, such as ozone, and radiation. Additionally, lightning-generated oxides of nitrogen influence both nitrate aerosol mass concentrations and aerosol size distribution, which has important implications for radiative fluxes and indirect aerosol effects.
Jiamao Zhou, Jiarui Wu, Xiaoli Su, Ruonan Wang, Xia Li, Qian Jiang, Ting Zhang, Wenting Dai, Junji Cao, Xuexi Tie, and Guohui Li
EGUsphere, https://doi.org/10.5194/egusphere-2024-3468, https://doi.org/10.5194/egusphere-2024-3468, 2024
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Brown carbon (BrC) is a type of airborne particle produced from various combustion sources which is light absorption. Historically, climate models have categorizing organic particles as either non-absorbing or purely reflective. Our study shows that BrC can reduce the usual cooling effect of organic particles. While BrC is often linked to biomass burning, however, BrC from fossil fuels contributes significantly to atmospheric heating.
Yanru Huo, Mingxue Li, Xueyu Wang, Jianfei Sun, Yuxin Zhou, Yuhui Ma, and Maoxia He
Atmos. Chem. Phys., 24, 12409–12423, https://doi.org/10.5194/acp-24-12409-2024, https://doi.org/10.5194/acp-24-12409-2024, 2024
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This work found that the air–water (A–W) interface and TiO2 clusters promote the oxidation of phenolic compounds (PhCs) to varying degrees compared with the gas phase and bulk water. Some byproducts are more harmful than their parent compounds. This work provides important evidence for the rapid oxidation observed in O3/HO• + PhC experiments at the A–W interface and in mineral dust.
Sijia Lou, Manish Shrivastava, Alexandre Albinet, Sophie Tomaz, Deepchandra Srivastava, Olivier Favez, Huizhong Shen, and Aijun Ding
EGUsphere, https://doi.org/10.5194/egusphere-2024-3269, https://doi.org/10.5194/egusphere-2024-3269, 2024
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PAHs, emitted from incomplete combustion, pose serious health risks due to their carcinogenic properties. This research demonstrates that viscous organic aerosol coatings significantly hinder PAH oxidation, with spatial distributions sensitive to the degradation modelling approach. Our findings underscore the importance of accurately modelling these processes for risk assessments, highlighting the need to consider both fresh and oxidized PAHs in evaluating human exposure and health risks.
Rémy Lapere, Louis Marelle, Pierre Rampal, Laurent Brodeau, Christian Melsheimer, Gunnar Spreen, and Jennie L. Thomas
Atmos. Chem. Phys., 24, 12107–12132, https://doi.org/10.5194/acp-24-12107-2024, https://doi.org/10.5194/acp-24-12107-2024, 2024
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Elongated open-water areas in sea ice, called leads, can release marine aerosols into the atmosphere. In the Arctic, this source of atmospheric particles could play an important role for climate. However, the amount, seasonality and spatial distribution of such emissions are all mostly unknown. Here, we propose a first parameterization for sea spray aerosols emitted through leads in sea ice and quantify their impact on aerosol populations in the high Arctic.
Hanzheng Zhu, Yaman Liu, Man Yue, Shihui Feng, Pingqing Fu, Kan Huang, Xinyi Dong, and Minghuai Wang
EGUsphere, https://doi.org/10.5194/egusphere-2024-2293, https://doi.org/10.5194/egusphere-2024-2293, 2024
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Dust soluble iron deposition from East Asia plays an important role in the marine ecology of the Northwest Pacific. Using the developed model, our findings highlight a dual trend: a decrease in the overall deposition of soluble iron from dust, but an increase in the solubility of the iron itself due to the enhanced atmospheric processing. It underscores the critical roles of both dust emission and atmospheric processing in soluble iron deposition and marine ecology.
Camilo Serrano Damha, Kyle Gorkowski, and Andreas Zuend
EGUsphere, https://doi.org/10.5194/egusphere-2024-2712, https://doi.org/10.5194/egusphere-2024-2712, 2024
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Organic aerosol water content impacts the gas–particle partitioning of semivolatile organics. We used an aerosol thermodynamic model in the GEOS-Chem chemical transport model to efficiently account for organic aerosol water uptake and nonideal mixing. This led to a substantial enhancement in mean organic aerosol mass concentration with respect to GEOS-Chem's most advanced scheme. The water-sensitive scheme could be a valuable tool for reconciling model estimations and field measurements.
Haihui Zhu, Randall V. Martin, Aaron van Donkelaar, Melanie S. Hammer, Chi Li, Jun Meng, Christopher R. Oxford, Xuan Liu, Yanshun Li, Dandan Zhang, Inderjeet Singh, and Alexei Lyapustin
Atmos. Chem. Phys., 24, 11565–11584, https://doi.org/10.5194/acp-24-11565-2024, https://doi.org/10.5194/acp-24-11565-2024, 2024
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Ambient fine particulate matter (PM2.5) contributes to 4 million deaths globally each year. Satellite remote sensing of aerosol optical depth (AOD), coupled with a simulated PM2.5–AOD relationship (η), can provide global PM2.5 estimations. This study aims to understand the spatial patterns and driving factors of η to guide future measurement and modeling efforts. We quantified η globally and regionally and found that its spatial variation is strongly influenced by aerosol composition.
Connor J. Clayton, Daniel R. Marsh, Steven T. Turnock, Ailish M. Graham, Kirsty J. Pringle, Carly L. Reddington, Rajesh Kumar, and James B. McQuaid
Atmos. Chem. Phys., 24, 10717–10740, https://doi.org/10.5194/acp-24-10717-2024, https://doi.org/10.5194/acp-24-10717-2024, 2024
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We demonstrate that strong climate mitigation could improve air quality in Europe; however, less ambitious mitigation does not result in these co-benefits. We use a high-resolution atmospheric chemistry model. This allows us to demonstrate how this varies across European countries and analyse the underlying chemistry. This may help policy-facing researchers understand which sectors and regions need to be prioritised to achieve strong air quality co-benefits of climate mitigation.
Ping-Chieh Huang, Hui-Ming Hung, Hsin-Chih Lai, and Charles C.-K. Chou
Atmos. Chem. Phys., 24, 10759–10772, https://doi.org/10.5194/acp-24-10759-2024, https://doi.org/10.5194/acp-24-10759-2024, 2024
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Models were used to study ways to reduce particulate matter (PM) pollution in Taiwan during winter. After considering various factors, such as physical processes and chemical reactions, we found that reducing NOx or NH3 emissions is more effective at mitigating PM2.5 than reducing SO2 emissions. When considering both efficiency and cost, reducing NH3 emissions seems to be a more suitable policy for the studied environment in Taiwan.
Matthieu Vida, Gilles Foret, Guillaume Siour, Florian Couvidat, Olivier Favez, Gaelle Uzu, Arineh Cholakian, Sébastien Conil, Matthias Beekmann, and Jean-Luc Jaffrezo
Atmos. Chem. Phys., 24, 10601–10615, https://doi.org/10.5194/acp-24-10601-2024, https://doi.org/10.5194/acp-24-10601-2024, 2024
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We simulate 2 years of atmospheric fungal spores over France and use observations of polyols and primary biogenic factors from positive matrix factorisation. The representation of emissions taking into account a proxy for vegetation surface and specific humidity enables us to reproduce very accurately the seasonal cycle of fungal spores. Furthermore, we estimate that fungal spores can account for 20 % of PM10 and 40 % of the organic fraction of PM10 over vegetated areas in summer.
Jiewen Shen, Bin Zhao, Shuxiao Wang, An Ning, Yuyang Li, Runlong Cai, Da Gao, Biwu Chu, Yang Gao, Manish Shrivastava, Jingkun Jiang, Xiuhui Zhang, and Hong He
Atmos. Chem. Phys., 24, 10261–10278, https://doi.org/10.5194/acp-24-10261-2024, https://doi.org/10.5194/acp-24-10261-2024, 2024
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We extensively compare various cluster-dynamics-based parameterizations for sulfuric acid–dimethylamine nucleation and identify a newly developed parameterization derived from Atmospheric Cluster Dynamic Code (ACDC) simulations as being the most reliable one. This study offers a valuable reference for developing parameterizations of other nucleation systems and is meaningful for the accurate quantification of the environmental and climate impacts of new particle formation.
Rubén Soussé-Villa, Oriol Jorba, María Gonçalves Ageitos, Dene Bowdalo, Marc Guevara, and Carlos Pérez García-Pando
EGUsphere, https://doi.org/10.5194/egusphere-2024-2310, https://doi.org/10.5194/egusphere-2024-2310, 2024
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Desert dust forms nitrate coatings as it travels through the atmosphere. However, current models that predict this process vary greatly due to different methods and inaccuracies. We examined how nitrate forms in a global model, focusing on how gases condense on dust, the lifespan of different particles, and the impact of alkalinity. Our findings show that models work best when they consider reversible gas condensation with alkalinity. This should lead to better estimates of climate impacts.
Ludovico Di Antonio, Matthias Beekmann, Guillaume Siour, Vincent Michoud, Christopher Cantrell, Astrid Bauville, Antonin Bergé, Mathieu Cazaunau, Servanne Chevaillier, Manuela Cirtog, Joel F. de Brito, Paola Formenti, Cecile Gaimoz, Olivier Garret, Aline Gratien, Valérie Gros, Martial Haeffelin, Lelia N. Hawkins, Simone Kotthaus, Gael Noyalet, Diana Pereira, Jean-Eudes Petit, Eva Drew Pronovost, Véronique Riffault, Chenjie Yu, Gilles Foret, Jean-François Doussin, and Claudia Di Biagio
EGUsphere, https://doi.org/10.5194/egusphere-2024-2175, https://doi.org/10.5194/egusphere-2024-2175, 2024
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Summer 2022 has been considered a proxy for future climate scenarios, given the registered hot and dry conditions. In this paper, we used the measurements from the ACROSS campaign, occurred over the Paris area in June–July 2022, in addition to observations from existing networks, to evaluate the WRF–CHIMERE model simulation over France and the Ile-de-France regions. Results over the Ile–de–France show to be satisfactory, allowing to explain the gas and aerosol variability at the ACROSS sites.
Wei Li and Yuxuan Wang
Atmos. Chem. Phys., 24, 9339–9353, https://doi.org/10.5194/acp-24-9339-2024, https://doi.org/10.5194/acp-24-9339-2024, 2024
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Droughts immensely increased organic aerosol (OA) in the contiguous United States in summer (1998–2019), notably in the Pacific Northwest (PNW) and Southeast (SEUS). The OA rise in the SEUS is driven by the enhanced formation of epoxydiol-derived secondary organic aerosol due to the increase in biogenic volatile organic compounds and sulfate, while in the PNW, it is caused by wildfires. A total of 10 climate models captured the OA increase in the PNW yet greatly underestimated it in the SEUS.
Weina Zhang, Jianhua Mai, Zhichao Fan, Yongpeng Ji, Yuemeng Ji, Guiying Li, Yanpeng Gao, and Taicheng An
Atmos. Chem. Phys., 24, 9019–9030, https://doi.org/10.5194/acp-24-9019-2024, https://doi.org/10.5194/acp-24-9019-2024, 2024
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This study reveals heterogeneous oxidation causes further radiative forcing effect (RFE) enhancement of amine–mineral mixed particles. Note that RFE increment is higher under clean conditions than that under polluted conditions, which is contributed to high-oxygen-content products. The enhanced RFE of amine–mineral particles caused by heterogenous oxidation is expected to alleviate warming effects.
Shenglan Jiang, Yan Zhang, Guangyuan Yu, Zimin Han, Junri Zhao, Tianle Zhang, and Mei Zheng
Atmos. Chem. Phys., 24, 8363–8381, https://doi.org/10.5194/acp-24-8363-2024, https://doi.org/10.5194/acp-24-8363-2024, 2024
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This study aims to provide gridded data on sea-wide concentrations, deposition fluxes, and soluble deposition fluxes with detailed source categories of metals using the modified CMAQ model. We developed a monthly emission inventory of six metals – Fe, Al, V, Ni, Zn, and Cu – from terrestrial anthropogenic, ship, and dust sources in East Asia in 2017. Our results reveal the contribution of each source to the emissions, concentrations, and deposition fluxes of metals in the East Asian seas.
Stelios Myriokefalitakis, Matthias Karl, Kim A. Weiss, Dimitris Karagiannis, Eleni Athanasopoulou, Anastasia Kakouri, Aikaterini Bougiatioti, Eleni Liakakou, Iasonas Stavroulas, Georgios Papangelis, Georgios Grivas, Despina Paraskevopoulou, Orestis Speyer, Nikolaos Mihalopoulos, and Evangelos Gerasopoulos
Atmos. Chem. Phys., 24, 7815–7835, https://doi.org/10.5194/acp-24-7815-2024, https://doi.org/10.5194/acp-24-7815-2024, 2024
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A state-of-the-art thermodynamic model has been coupled with the city-scale chemistry transport model EPISODE–CityChem to investigate the equilibrium between the inorganic gas and aerosol phases over the greater Athens area, Greece. The simulations indicate that the formation of nitrates in an urban environment is significantly affected by local nitrogen oxide emissions, as well as ambient temperature, relative humidity, photochemical activity, and the presence of non-volatile cations.
Rui Li, Yining Gao, Lijia Zhang, Yubing Shen, Tianzhao Xu, Wenwen Sun, and Gehui Wang
Atmos. Chem. Phys., 24, 7623–7636, https://doi.org/10.5194/acp-24-7623-2024, https://doi.org/10.5194/acp-24-7623-2024, 2024
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A three-stage model was developed to obtain the global maps of reactive nitrogen components during 2000–2100. The results implied that cross-validation R2 values of four species showed satisfactory performance (R2 > 0.55). Most reactive nitrogen components, except NH3, in China showed increases during 2000–2013. In the future scenarios, SSP3-7.0 (traditional-energy scenario) and SSP1-2.6 (carbon neutrality scenario) showed the highest and lowest reactive nitrogen component concentrations.
Fei Ye, Jingyi Li, Yaqin Gao, Hongli Wang, Jingyu An, Cheng Huang, Song Guo, Keding Lu, Kangjia Gong, Haowen Zhang, Momei Qin, and Jianlin Hu
Atmos. Chem. Phys., 24, 7467–7479, https://doi.org/10.5194/acp-24-7467-2024, https://doi.org/10.5194/acp-24-7467-2024, 2024
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Naphthalene (Nap) and methylnaphthalene (MN) are key precursors of secondary organic aerosol (SOA), yet their sources and sinks are often inadequately represented in air quality models. In this study, we incorporated detailed emissions, gas-phase chemistry, and SOA parameterization of Nap and MN into CMAQ to address this issue. The findings revealed remarkably high SOA formation potentials for these compounds despite their low emissions in the Yangtze River Delta region during summer.
Vy Dinh Ngoc Thuy, Jean-Luc Jaffrezo, Ian Hough, Pamela A. Dominutti, Guillaume Salque Moreton, Grégory Gille, Florie Francony, Arabelle Patron-Anquez, Olivier Favez, and Gaëlle Uzu
Atmos. Chem. Phys., 24, 7261–7282, https://doi.org/10.5194/acp-24-7261-2024, https://doi.org/10.5194/acp-24-7261-2024, 2024
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The capacity of particulate matter (PM) to generate reactive oxygen species in vivo is represented by oxidative potential (OP). This study focuses on finding the appropriate model to evaluate the oxidative character of PM sources in six sites using the PM sources and OP. Eight regression techniques are introduced to assess the OP of PM. The study highlights the importance of selecting a model according to the input data characteristics and establishes some recommendations for the procedure.
Ming Chu, Xing Wei, Shangfei Hai, Yang Gao, Huiwang Gao, Yujiao Zhu, Biwu Chu, Nan Ma, Juan Hong, Yele Sun, and Xiaohong Yao
Atmos. Chem. Phys., 24, 6769–6786, https://doi.org/10.5194/acp-24-6769-2024, https://doi.org/10.5194/acp-24-6769-2024, 2024
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We used a 20-bin WRF-Chem model to simulate NPF events in the NCP during a three-week observational period in the summer of 2019. The model was able to reproduce the observations during June 29–July 6, which was characterized by a high frequency of NPF occurrence.
Haoqi Wang, Xiao Tian, Wanting Zhao, Jiacheng Li, Haoyu Yu, Yinchang Feng, and Shaojie Song
Atmos. Chem. Phys., 24, 6583–6592, https://doi.org/10.5194/acp-24-6583-2024, https://doi.org/10.5194/acp-24-6583-2024, 2024
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pH is a key property of ambient aerosols, which affect many atmospheric processes. As aerosol pH is a non-conservative parameter, diverse averaging metrics and temporal resolutions may influence the pH values calculated by thermodynamic models. This technical note seeks to quantitatively evaluate the average pH using varied metrics and resolutions. The ultimate goal is to establish standardized reporting practices in future research endeavors.
Jiwon Choi, Myoseon Jang, and Spencer Blau
Atmos. Chem. Phys., 24, 6567–6582, https://doi.org/10.5194/acp-24-6567-2024, https://doi.org/10.5194/acp-24-6567-2024, 2024
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Persistent phenoxy radical (PPR), formed by phenol gas oxidation and its aqueous reaction, catalytically destroys O3 and retards secondary organic aerosol (SOA) growth. Explicit gas mechanisms including the formation of PPR and low-volatility products from the oxidation of phenol or benzene are applied to the UNIPAR model to predict SOA mass via multiphase reactions of precursors. Aqueous reactions of reactive organics increase SOA mass but retard SOA growth via heterogeneously formed PPR.
Yang Yang, Shaoxuan Mou, Hailong Wang, Pinya Wang, Baojie Li, and Hong Liao
Atmos. Chem. Phys., 24, 6509–6523, https://doi.org/10.5194/acp-24-6509-2024, https://doi.org/10.5194/acp-24-6509-2024, 2024
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The variations in anthropogenic aerosol concentrations and source contributions and their subsequent radiative impact in major emission regions during historical periods are quantified based on an aerosol-tagging system in E3SMv1. Due to the industrial development and implementation of economic policies, sources of anthropogenic aerosols show different variations, which has important implications for pollution prevention and control measures and decision-making for global collaboration.
Maegan A. DeLessio, Kostas Tsigaridis, Susanne E. Bauer, Jacek Chowdhary, and Gregory L. Schuster
Atmos. Chem. Phys., 24, 6275–6304, https://doi.org/10.5194/acp-24-6275-2024, https://doi.org/10.5194/acp-24-6275-2024, 2024
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This study presents the first explicit representation of brown carbon aerosols in the GISS ModelE Earth system model (ESM). Model sensitivity to a range of brown carbon parameters and model performance compared to AERONET and MODIS retrievals of total aerosol properties were assessed. A summary of best practices for incorporating brown carbon into ModelE is also included.
Chuanyang Shen, Xiaoyan Yang, Joel Thornton, John Shilling, Chenyang Bi, Gabriel Isaacman-VanWertz, and Haofei Zhang
Atmos. Chem. Phys., 24, 6153–6175, https://doi.org/10.5194/acp-24-6153-2024, https://doi.org/10.5194/acp-24-6153-2024, 2024
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In this work, a condensed multiphase isoprene oxidation mechanism was developed to simulate isoprene SOA formation from chamber and field studies. Our results show that the measured isoprene SOA mass concentrations can be reasonably reproduced. The simulation results indicate that multifunctional low-volatility products contribute significantly to total isoprene SOA. Our findings emphasize that the pathways to produce these low-volatility species should be considered in models.
Alice Maison, Lya Lugon, Soo-Jin Park, Alexia Baudic, Christopher Cantrell, Florian Couvidat, Barbara D'Anna, Claudia Di Biagio, Aline Gratien, Valérie Gros, Carmen Kalalian, Julien Kammer, Vincent Michoud, Jean-Eudes Petit, Marwa Shahin, Leila Simon, Myrto Valari, Jérémy Vigneron, Andrée Tuzet, and Karine Sartelet
Atmos. Chem. Phys., 24, 6011–6046, https://doi.org/10.5194/acp-24-6011-2024, https://doi.org/10.5194/acp-24-6011-2024, 2024
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This study presents the development of a bottom-up inventory of urban tree biogenic emissions. Emissions are computed for each tree based on their location and characteristics and are integrated in the regional air quality model WRF-CHIMERE. The impact of these biogenic emissions on air quality is quantified for June–July 2022. Over Paris city, urban trees increase the concentrations of particulate organic matter by 4.6 %, of PM2.5 by 0.6 %, and of ozone by 1.0 % on average over 2 months.
Tommaso Galeazzo, Bernard Aumont, Marie Camredon, Richard Valorso, Yong B. Lim, Paul J. Ziemann, and Manabu Shiraiwa
Atmos. Chem. Phys., 24, 5549–5565, https://doi.org/10.5194/acp-24-5549-2024, https://doi.org/10.5194/acp-24-5549-2024, 2024
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Secondary organic aerosol (SOA) derived from n-alkanes is a major component of anthropogenic particulate matter. We provide an analysis of n-alkane SOA by chemistry modeling, machine learning, and laboratory experiments, showing that n-alkane SOA adopts low-viscous semi-solid or liquid states. Our results indicate few kinetic limitations of mass accommodation in SOA formation, supporting the application of equilibrium partitioning for simulating n-alkane SOA in large-scale atmospheric models.
Bin Luo, Yuqiang Zhang, Tao Tang, Hongliang Zhang, Jianlin Hu, Jiangshan Mu, Wenxing Wang, and Likun Xue
EGUsphere, https://doi.org/10.5194/egusphere-2024-974, https://doi.org/10.5194/egusphere-2024-974, 2024
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India is facing a severe air pollution crisis that poses significant health risks, particularly from PM2.5 and O3. Our study reveals rising levels of both pollutants from 1995 to 2014, leading to increased premature mortality. While anthropogenic emissions play a significant role, biomass burning also impacts air quality, in particular seasons and regions in India. This study highlights the urgent need for localized policies to protect public health amid escalating environmental challenges.
Lukáš Bartík, Peter Huszár, Jan Karlický, Ondřej Vlček, and Kryštof Eben
Atmos. Chem. Phys., 24, 4347–4387, https://doi.org/10.5194/acp-24-4347-2024, https://doi.org/10.5194/acp-24-4347-2024, 2024
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The presented study deals with the attribution of fine particulate matter (PM2.5) concentrations to anthropogenic emissions over Central Europe using regional-scale models. It calculates the present-day contributions of different emissions sectors to concentrations of PM2.5 and its secondary components. Moreover, the study investigates the effect of chemical nonlinearities by using multiple source attribution methods and secondary organic aerosol calculation methods.
Rui Wang, Yang Cheng, Shasha Chen, Rongrong Li, Yue Hu, Xiaokai Guo, Tianlei Zhang, Fengmin Song, and Hao Li
Atmos. Chem. Phys., 24, 4029–4046, https://doi.org/10.5194/acp-24-4029-2024, https://doi.org/10.5194/acp-24-4029-2024, 2024
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We used quantum chemical calculations, Born–Oppenheimer molecular dynamics simulations, and the ACDC kinetic model to characterize SO3–H2SO4 interaction in the gas phase and at the air–water interface and to study the effect of H2S2O7 on H2SO4–NH3-based clusters. The work expands our understanding of new pathways for the loss of SO3 in acidic polluted areas and helps reveal some missing sources of NPF in metropolitan industrial regions and understand the atmospheric organic–sulfur cycle better.
Hao Yang, Lei Chen, Hong Liao, Jia Zhu, Wenjie Wang, and Xin Li
Atmos. Chem. Phys., 24, 4001–4015, https://doi.org/10.5194/acp-24-4001-2024, https://doi.org/10.5194/acp-24-4001-2024, 2024
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The present study quantifies the response of aerosol–radiation interaction (ARI) to anthropogenic emission reduction from 2013 to 2017, with the main focus on the contribution to changed O3 concentrations over eastern China both in summer and winter using the WRF-Chem model. The weakened ARI due to decreased anthropogenic emission aggravates the summer (winter) O3 pollution by +0.81 ppb (+0.63 ppb), averaged over eastern China.
Margaret R. Marvin, Paul I. Palmer, Fei Yao, Mohd Talib Latif, and Md Firoz Khan
Atmos. Chem. Phys., 24, 3699–3715, https://doi.org/10.5194/acp-24-3699-2024, https://doi.org/10.5194/acp-24-3699-2024, 2024
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We use an atmospheric chemistry model to investigate aerosols emitted from fire activity across Southeast Asia. We find that the limited nature of measurements in this region leads to large uncertainties that significantly hinder the model representation of these aerosols and their impacts on air quality. As a result, the number of monthly attributable deaths is underestimated by as many as 4500, particularly in March at the peak of the mainland burning season.
Julie Camman, Benjamin Chazeau, Nicolas Marchand, Amandine Durand, Grégory Gille, Ludovic Lanzi, Jean-Luc Jaffrezo, Henri Wortham, and Gaëlle Uzu
Atmos. Chem. Phys., 24, 3257–3278, https://doi.org/10.5194/acp-24-3257-2024, https://doi.org/10.5194/acp-24-3257-2024, 2024
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Fine particle (PM1) pollution is a major health issue in the city of Marseille, which is subject to numerous pollution sources. Sampling carried out during the summer enabled a fine characterization of the PM1 sources and their oxidative potential, a promising new metric as a proxy for health impact. PM1 came mainly from combustion sources, secondary ammonium sulfate, and organic nitrate, while the oxidative potential of PM1 came from these sources and from resuspended dust in the atmosphere.
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Ervens, B., Turpin, B. J., and Weber, R. J.: Secondary organic aerosol formation in cloud droplets and aqueous particles (aqSOA): a review of laboratory, field and model studies, Atmos. Chem. Phys., 11, 11069–11102, https://doi.org/10.5194/acp-11-11069-2011, 2011.
Galloway, M. M., Chhabra, P. S., Chan, A. W. H., Surratt, J. D., Flagan, R. C., Seinfeld, J. H., and Keutsch, F. N.: Glyoxal uptake on ammonium sulphate seed aerosol: reaction products and reversibility of uptake under dark and irradiated conditions, Atmos. Chem. Phys., 9, 3331–3345, https://doi.org/10.5194/acp-9-3331-2009, 2009.
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