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.
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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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
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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.
Vikram Pratap, Christopher J. Hennigan, Bastian Stieger, Andreas Tilgner, Laurent Poulain, Dominik van Pinxteren, Gerald Spindler, and Hartmut Herrmann
Atmos. Chem. Phys., 25, 8871–8889, https://doi.org/10.5194/acp-25-8871-2025, https://doi.org/10.5194/acp-25-8871-2025, 2025
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In this work, we characterize trends in aerosol pH and its controlling factors during the period 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 particulate matter in the region.
Daniel L. Goldberg, M. Omar Nawaz, Congmeng Lyu, Jian He, Annmarie G. Carlton, Shobha Kondragunta, and Susan C. Anenberg
EGUsphere, https://doi.org/10.5194/egusphere-2025-1350, https://doi.org/10.5194/egusphere-2025-1350, 2025
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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.
Christopher J. Hennigan, Michael McKee, Vikram Pratap, Bryanna Boegner, Jasper Reno, Lucia Garcia, Madison McLaren, and Sara M. Lance
Atmos. Chem. Phys., 23, 14437–14449, https://doi.org/10.5194/acp-23-14437-2023, https://doi.org/10.5194/acp-23-14437-2023, 2023
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This study characterized the optical properties of light-absorbing organic compounds, called brown carbon (BrC), in atmospheric cloud water samples. In all samples, light absorption by BrC increased linearly with increasing pH. There was variability in the sensitivity of the absorption–pH relationship, depending on the degree of influence from fire emissions. Overall, these results show that the climate forcing of BrC is quite strongly affected by its pH-dependent absorption.
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
Geosci. Model Dev., 16, 3873–3891, https://doi.org/10.5194/gmd-16-3873-2023, https://doi.org/10.5194/gmd-16-3873-2023, 2023
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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.
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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Coastal regions are susceptible to variable and high ozone which is difficult to simulate. We developed a method to characterize large datasets of multi-dimensional measurements from lidar instruments taken in coastal regions. Using the clustered ozone groups, we evaluated model performance in simulating the coastal ozone variability vertically and diurnally. The approach allowed us to pinpoint areas where the models succeed in simulating coastal ozone and areas where there are still gaps.
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
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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.
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
Atmos. Chem. Phys., 21, 11133–11160, https://doi.org/10.5194/acp-21-11133-2021, https://doi.org/10.5194/acp-21-11133-2021, 2021
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Comprehensive evaluations of simulated diurnal cycles of NO2 and NOy concentrations, vertical profiles, and tropospheric vertical column densities at two different resolutions with various measurements during the DISCOVER-AQ 2011 campaign show potential distribution biases of NOx emissions in the National Emissions Inventory 2011 at both 36 and 4 km resolutions, providing another possible explanation for the overestimation of model results.
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
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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.
Havala O. T. Pye, Athanasios Nenes, Becky Alexander, Andrew P. Ault, Mary C. Barth, Simon L. Clegg, Jeffrey L. Collett Jr., Kathleen M. Fahey, Christopher J. Hennigan, Hartmut Herrmann, Maria Kanakidou, James T. Kelly, I-Ting Ku, V. Faye McNeill, Nicole Riemer, Thomas Schaefer, Guoliang Shi, Andreas Tilgner, John T. Walker, Tao Wang, Rodney Weber, Jia Xing, Rahul A. Zaveri, and Andreas Zuend
Atmos. Chem. Phys., 20, 4809–4888, https://doi.org/10.5194/acp-20-4809-2020, https://doi.org/10.5194/acp-20-4809-2020, 2020
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Acid rain is recognized for its impacts on human health and ecosystems, and programs to mitigate these effects have had implications for atmospheric acidity. Historical measurements indicate that cloud and fog droplet acidity has changed in recent decades in response to controls on emissions from human activity, while the limited trend data for suspended particles indicate acidity may be relatively constant. This review synthesizes knowledge on the acidity of atmospheric particles and clouds.
Michael A. Battaglia Jr., Rodney J. Weber, Athanasios Nenes, and Christopher J. Hennigan
Atmos. Chem. Phys., 19, 14607–14620, https://doi.org/10.5194/acp-19-14607-2019, https://doi.org/10.5194/acp-19-14607-2019, 2019
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The effects of water-soluble organic carbon (WSOC) on aerosol pH were characterized for aqueous-phase particles containing a mixture of inorganics and organics. The ISORROPIA-II and E-AIM models were used in conjunction with AIOMFAC to quantify the effect of organics on aerosol pH through (1) changes to the aerosol liquid water content and (2) changes to the hydrogen ion activity coefficient. The study included both organic acids and nonacids, at RH levels ranging from 70 to 90 %.
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
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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.
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
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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.
Marwa M. H. El-Sayed, Diana L. Ortiz-Montalvo, and Christopher J. Hennigan
Atmos. Chem. Phys., 18, 1171–1184, https://doi.org/10.5194/acp-18-1171-2018, https://doi.org/10.5194/acp-18-1171-2018, 2018
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We characterized the reversibility of aqSOA formed from isoprene at a location in the eastern United States. WSOCp evaporation with drying was observed systematically throughout the late spring and summer, indicating reversible aqSOA formation. The absolute reversible aqSOA concentrations, as well as the relative amount of reversible aqSOA, increased with decreasing NOx / isoprene ratios, suggesting that IEPOX or other low-NOx oxidation products were responsible for these effects.
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
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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.
Travis N. Knepp, James J. Szykman, Russell Long, Rachelle M. Duvall, Jonathan Krug, Melinda Beaver, Kevin Cavender, Keith Kronmiller, Michael Wheeler, Ruben Delgado, Raymond Hoff, Timothy Berkoff, Erik Olson, Richard Clark, Daniel Wolfe, David Van Gilst, and Doreen Neil
Atmos. Meas. Tech., 10, 3963–3983, https://doi.org/10.5194/amt-10-3963-2017, https://doi.org/10.5194/amt-10-3963-2017, 2017
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Herein we compare the mixed-layer data products from differing ceilometer instruments and meteorological sondes.
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
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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.
Laura Bianco, Katja Friedrich, James M. Wilczak, Duane Hazen, Daniel Wolfe, Ruben Delgado, Steven P. Oncley, and Julie K. Lundquist
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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XPIA is a study held in 2015 at NOAA's Boulder Atmospheric Observatory facility, aimed at assessing remote-sensing capabilities for wind energy applications. We use well-defined reference systems to validate temperature retrieved by two microwave radiometers (MWRs) and virtual temperature measured by wind profiling radars with radio acoustic sounding systems (RASSs). Water vapor density and relative humidity by the MWRs were also compared with similar measurements from the reference systems.
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
Geosci. Model Dev., 10, 1587–1605, https://doi.org/10.5194/gmd-10-1587-2017, https://doi.org/10.5194/gmd-10-1587-2017, 2017
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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)
Climatology of aerosol pH and its controlling factors at the Melpitz continental background site in Central Europe
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Advances in characterization of black carbon particles and their associated coatings using the soot-particle aerosol mass spectrometer in Singapore, a complex city environment
Iron isotopes suggest significant aerosol dissolution over the Pacific Ocean
Enrichment of organic nitrogen in fog residuals observed in the Italian Po Valley
Asian dust transport of proteinaceous matter from the Gobi Desert to northern China
Machine-learning-assisted chemical characterization and optical properties of atmospheric brown carbon in Nanjing, China
Technical note: Reconstructing missing surface aerosol elemental carbon data in long-term series with ensemble learning
Enhanced emission of intermediate-volatility/semi-volatile organic matter in gas and particle phases from ship exhausts with low-sulfur fuels
Measurement report: Crustal materials play an increasing role in elevating particle pH – insights from 12-year records in a typical inland city of China
Significant contributions of biomass burning to PM2.5-bound aromatic compounds: insights from field observations and quantum chemical calculations
Measurement report: In-depth characterization of ship emissions during operations in a Mediterranean port
Direct measurement of N2O5 heterogeneous uptake coefficients on atmospheric aerosols in southwestern China and evaluation of current parameterizations
Measurement report: Per- and polyfluoroalkyl substances (PFAS) in particulate matter (PM10) from activated sludge aeration
African dust transported to Barbados in the wintertime lacks indicators of chemical aging
A 60-year atmospheric nitrate isotope record from a southeastern Greenland ice core with minimal postdepositional alteration
Measurement report: Characterization of aerosol hygroscopicity over Southeast Asia during the NASA CAMP2Ex campaign
Long–term Trends in PM2.5 Chemical Composition and Its Impact on Aerosol Properties: Field Observations from 2007 to 2020 in Pearl River Delta, South China
Atmospheric Organosulfate Formation Regulated by Continental Outflows and Marine Emissions over East Asian Marginal Seas
Individual particle compositions and aerosol mixing states at different altitudes over the ocean in East Asia
Molecular characterization of organic aerosols in urban and forested areas of Paris using high-resolution mass spectrometry
Measurement report: Wintertime aerosol characterization at an urban traffic site in Helsinki, Finland
Source apportionment and ecotoxicity of PM2.5 pollution events in a major Southern Hemisphere megacity: influence of a biofuel-impacted fleet and biomass burning
The impacts of pollution sources and temperature on the light absorption of HULIS were revealed by UHPLC-HRMS/MS at the molecular structure level
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
Measurement report: Sources and meteorology influencing highly time-resolved PM2.5 trace elements at three urban sites in the extremely polluted Indo-Gangetic Plain in India
Formation of highly absorptive secondary brown carbon through nighttime multiphase chemistry of biomass burning emissions
Hydroxymethanesulfonate (HMS) Formation under Urban and Marine Atmosphere: role of aerosol ionic strength
The sources and diurnal variations of submicron aerosols in a coastal-rural environment near Houston, US
Measurement report: Vertically resolved atmospheric properties observed over the Southern Great Plains with the ArcticShark uncrewed aerial system
Unraveling Arctic submicron organic aerosol sources: a year-long study by H-NMR and AMS in Ny-Ålesund, Svalbard
Non-biogenic sources are an important but overlooked contributor to aerosol isoprene-derived organosulfates during winter in northern China
Unveiling single-particle composition, size, shape, and mixing state of freshly emitted Icelandic dust via electron microscopy analysis
The Critical Role of Volatile Organic Compounds Emission in Nitrate Formation in Lhasa, Tibetan Plateau: Insights from Oxygen Isotope Anomaly Measurements
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
Burning conditions and transportation pathways determine biomass-burning aerosol properties in the Ascension Island marine boundary layer
Observations of high-time-resolution and size-resolved aerosol chemical composition and microphysics in the central Arctic: implications for climate-relevant particle properties
A critical review of the use of iron isotopes in atmospheric aerosol research
Measurement report: Brown carbon aerosol in rural Germany – sources, chemistry, and diurnal variations
Atmospheric chemistry in East Asia determines the iron solubility of aerosol particles supplied to the North Pacific Ocean
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
Multiple eco-regions contribute to the seasonal cycle of Antarctic aerosol size distributions
Seasonal investigation of ultrafine-particle organic composition in an eastern Amazonian rainforest
Vikram Pratap, Christopher J. Hennigan, Bastian Stieger, Andreas Tilgner, Laurent Poulain, Dominik van Pinxteren, Gerald Spindler, and Hartmut Herrmann
Atmos. Chem. Phys., 25, 8871–8889, https://doi.org/10.5194/acp-25-8871-2025, https://doi.org/10.5194/acp-25-8871-2025, 2025
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In this work, we characterize trends in aerosol pH and its controlling factors during the period 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 particulate matter in the region.
Yuan Cheng, Ying-jie Zhong, Zhi-qing Zhang, Xu-bing Cao, and Jiu-meng Liu
Atmos. Chem. Phys., 25, 8493–8505, https://doi.org/10.5194/acp-25-8493-2025, https://doi.org/10.5194/acp-25-8493-2025, 2025
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As an emerging hotspot of atmospheric sciences, northeastern 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 in the exploration of PM2.5 sources in northeastern China, which are essential for further improving the regional air quality.
Theresa Mathes, Heather Guy, John Prytherch, Julia Kojoj, Ian Brooks, Sonja Murto, Paul Zieger, Birgit Wehner, Michael Tjernström, and Andreas Held
Atmos. Chem. Phys., 25, 8455–8474, https://doi.org/10.5194/acp-25-8455-2025, https://doi.org/10.5194/acp-25-8455-2025, 2025
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The Arctic is warming faster than the global average and an investigation of aerosol–cloud–sea ice interactions is crucial for studying its climate system. During the ARTofMELT Expedition 2023, particle and sensible heat fluxes were measured over different surfaces. Wide lead surfaces acted as particle sources, with the strongest sensible heat fluxes, while closed ice surfaces acted as particle sinks. In this study, methods to measure these interactions are improved, enhancing our understanding of Arctic climate processes.
Mutian Ma, Laura-Hélèna Rivellini, Yichen Zong, Markus Kraft, Liya E. Yu, and Alex King Yin Lee
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.
Yunfeng He, Xiang Ding, Quanfu He, Yuqing Zhang, Duohong Chen, Tao Zhang, Kong Yang, Junqi Wang, Qian Cheng, Hao Jiang, Zirui Wang, Ping Liu, Xinming Wang, and Michael Boy
EGUsphere, https://doi.org/10.5194/egusphere-2025-2204, https://doi.org/10.5194/egusphere-2025-2204, 2025
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The long-term field measurements in the Pearl River Delta revealed a significant decline in PM2.5 main components. As air quality improved, secondary species became more dominant. In addition, the proportion of nitrate had doubled. The changes in chemical composition led to the reductions in aerosol acidity, liquid water content and light extinction coefficient. Our results help to improve understanding of the secondary species formation under decreasing anthropogenic emissions.
Shubin Li, Yujue Wang, Yiwen Zhang, Yizhe Yi, Yuchen Wang, Yuqi Guo, Chao Yu, Yue Jiang, Jinhui Shi, Chao Zhang, Jialei Zhu, Wei Hu, Jianzhen Yu, Xiaohong Yao, Huiwang Gao, and Min Hu
EGUsphere, https://doi.org/10.5194/egusphere-2025-2154, https://doi.org/10.5194/egusphere-2025-2154, 2025
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Organosulfates (OSs) are an unrecognized and potentially important component in marine organic aerosols. In this study, we quantified and characterized the OSs over East Asian marginal seas. The chemical nature and spatiotemporal distribution of OSs were modified by the joint influence of marine emissions and transported terrestrial pollutants. The results highlight the vital roles of OSs in shaping organic aerosol formation and sulfur cycle during summer in marine boundary layer.
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.
Jing Li, Jiaoshi Zhang, Xianda Gong, Steven Spielman, Chongai Kuang, Ashish Singh, Maria A. Zawadowicz, Lu Xu, and Jian Wang
EGUsphere, https://doi.org/10.5194/egusphere-2025-726, https://doi.org/10.5194/egusphere-2025-726, 2025
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Using measurements at a rural coastal site, we quantified aerosols in representative air masses and identified major source of organics in Houston area. Our results show cooking aerosol is likely overestimated by earlier studies. Additionally, diurnal variation of highly oxidized organics is mostly driven by air mass changes instead of photochemistry. This study highlights the impacts of emissions, atmospheric chemistry, and meteorology on aerosol properties in the coastal-rural environment.
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.
Marco Paglione, Yufang Hao, Stefano Decesari, Mara Russo, Karam Mansour, Mauro Mazzola, Diego Fellin, Andrea Mazzanti, Emilio Tagliavini, Manousos Ioannis Manousakas, Evangelia Diapouli, Elena Barbaro, Matteo Feltracco, Kaspar Rudolf Daellenbach, and Matteo Rinaldi
EGUsphere, https://doi.org/10.5194/egusphere-2025-760, https://doi.org/10.5194/egusphere-2025-760, 2025
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A year-long set of PM1 samples from Ny-Ålesund, Svalbard, was analyzed by H-NMR and HR-TOF-AMS for the chemical characterization of the organic fraction. Positive Matrix Factorization allowed to identify five organic aerosol sources with specific seasonality. Winter-spring aerosol is dominated by Eurasian pollution, while summer is characterized by biogenic aerosols from marine sources; occasional summertime high OA loadings are associated with wildfire aerosols.
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.
Yifan Zhang, Rui Li, Zachary B. Bunnell, Yizhu Chen, Guanhong Zhu, Jinlong Ma, Guohua Zhang, Tim M. Conway, and Mingjin Tang
EGUsphere, https://doi.org/10.5194/egusphere-2025-474, https://doi.org/10.5194/egusphere-2025-474, 2025
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The sources of aerosol Fe, especially soluble aerosol Fe, remain to be constrained. The stable isotope ratio of Fe (δ56Fe) has emerged as a potential tracer for discriminating and quantifying sources of aerosol Fe. In this review, we examine the state of the field for using δ56Fe as an aerosol source tracer, and constraints on endmember signatures.
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.
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.
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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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