Articles | Volume 16, issue 10
https://doi.org/10.5194/acp-16-6511-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue:
https://doi.org/10.5194/acp-16-6511-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
27 May 2016
Research article |
| 27 May 2016
Understanding the optical properties of ambient sub- and supermicron particulate matter: results from the CARES 2010 field study in northern California
Department of Civil and Environmental Engineering, University of California, Davis, CA 95616, USA
Katheryn R. Kolesar
Department of Civil and Environmental Engineering, University of California, Davis, CA 95616, USA
now at: Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
Xiaolu Zhang
Department of Civil and Environmental Engineering, University of California, Davis, CA 95616, USA
Dean B. Atkinson
Department of Chemistry, Portland State University, Portland, OR 92707, USA
Mikhail S. Pekour
Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
Rahul A. Zaveri
Atmospheric Sciences & Global Change Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
Alla Zelenyuk
Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
Department of Environmental Toxicology, University of California, Davis, CA 95616, USA
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Jianlin Hu, Shantanu Jathar, Hongliang Zhang, Qi Ying, Shu-Hua Chen, Christopher D. Cappa, and Michael J. Kleeman
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M. Dale Stokes, Grant Deane, Douglas B. Collins, Christopher Cappa, Timothy Bertram, Abigail Dommer, Steven Schill, Sara Forestieri, and Mathew Survilo
Atmos. Meas. Tech., 9, 4257–4267, https://doi.org/10.5194/amt-9-4257-2016, https://doi.org/10.5194/amt-9-4257-2016, 2016
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A small breaking wave and foam simulator has been fabricated that allows the continuous analysis of the produced marine aerosols. Based on the original Marine Aerosol Reference Tank (MART) the miniature version allows the culturing of delicate planktonic organisms because it operates without a large, sheer-inducing pump. This allows the study of marine aerosol production and the effects of biologically controlled seawater chemistry under controlled and repeatable experimental conditions.
Sara D. Forestieri, Gavin C. Cornwell, Taylor M. Helgestad, Kathryn A. Moore, Christopher Lee, Gordon A. Novak, Camille M. Sultana, Xiaofei Wang, Timothy H. Bertram, Kimberly A. Prather, and Christopher D. Cappa
Atmos. Chem. Phys., 16, 9003–9018, https://doi.org/10.5194/acp-16-9003-2016, https://doi.org/10.5194/acp-16-9003-2016, 2016
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Alma Hodzic, Prasad S. Kasibhatla, Duseong S. Jo, Christopher D. Cappa, Jose L. Jimenez, Sasha Madronich, and Rokjin J. Park
Atmos. Chem. Phys., 16, 7917–7941, https://doi.org/10.5194/acp-16-7917-2016, https://doi.org/10.5194/acp-16-7917-2016, 2016
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Dominique E. Young, Hwajin Kim, Caroline Parworth, Shan Zhou, Xiaolu Zhang, Christopher D. Cappa, Roger Seco, Saewung Kim, and Qi Zhang
Atmos. Chem. Phys., 16, 5427–5451, https://doi.org/10.5194/acp-16-5427-2016, https://doi.org/10.5194/acp-16-5427-2016, 2016
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Aerosol chemistry and the sources and processes driving the observed temporal and diurnal variations of PM were studied in a polluted urban environment during winter 2013. These results were compared to a similar campaign from winter 2010. Meteorology strongly influenced PM composition, both directly and indirectly. Nighttime reactions played a more important role in 2013 and the influence from a nighttime formed residual layer that mixed down in the morning was also much more intense in 2013.
Christopher D. Cappa, Shantanu H. Jathar, Michael J. Kleeman, Kenneth S. Docherty, Jose L. Jimenez, John H. Seinfeld, and Anthony S. Wexler
Atmos. Chem. Phys., 16, 3041–3059, https://doi.org/10.5194/acp-16-3041-2016, https://doi.org/10.5194/acp-16-3041-2016, 2016
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S. H. Jathar, C. D. Cappa, A. S. Wexler, J. H. Seinfeld, and M. J. Kleeman
Atmos. Chem. Phys., 16, 2309–2322, https://doi.org/10.5194/acp-16-2309-2016, https://doi.org/10.5194/acp-16-2309-2016, 2016
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Multi-generational chemistry schemes applied in regional models do not increase secondary organic aerosol (SOA) mass production relative to traditional "two-product" schemes when both models are fitted to the same chamber data. The multi-generational chemistry schemes do change the predicted composition of SOA and the source attribution of SOA.
K. R. Kolesar, C. Chen, D. Johnson, and C. D. Cappa
Atmos. Chem. Phys., 15, 9327–9343, https://doi.org/10.5194/acp-15-9327-2015, https://doi.org/10.5194/acp-15-9327-2015, 2015
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S. H. Jathar, C. D. Cappa, A. S. Wexler, J. H. Seinfeld, and M. J. Kleeman
Geosci. Model Dev., 8, 2553–2567, https://doi.org/10.5194/gmd-8-2553-2015, https://doi.org/10.5194/gmd-8-2553-2015, 2015
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Multi-generational oxidation of organic vapors can significantly alter the mass, chemical composition and properties of secondary organic aerosol (SOA). Here, we implement a semi-explicit, constrained multi-generational oxidation model of Cappa and Wilson (2012) in a 3-D air quality model. When compared with results from a current-generation SOA model, we predict similar mass concentrations of SOA but a different chemical composition. O:C ratios of SOA are in line with those measured globally.
D. B. Atkinson, J. G. Radney, J. Lum, K. R. Kolesar, D. J. Cziczo, M. S. Pekour, Q. Zhang, A. Setyan, A. Zelenyuk, and C. D. Cappa
Atmos. Chem. Phys., 15, 4045–4061, https://doi.org/10.5194/acp-15-4045-2015, https://doi.org/10.5194/acp-15-4045-2015, 2015
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This work describes an analysis of measurements of the influence of water uptake on the light-scattering properties of sub- and supermicron-sized particles as observed in the Sacramento, CA, USA region during the 2010 CARES field campaign. The observations are used to derive campaign-average effective hygroscopicity parameters for submicron oxygenated organic aerosol and for supermicron particles, and the influence of chloride displacement reactions on particle hygroscopicity is examined.
G. M. Buffaloe, D. A. Lack, E. J. Williams, D. Coffman, K. L. Hayden, B. M. Lerner, S.-M. Li, I. Nuaaman, P. Massoli, T. B. Onasch, P. K. Quinn, and C. D. Cappa
Atmos. Chem. Phys., 14, 1881–1896, https://doi.org/10.5194/acp-14-1881-2014, https://doi.org/10.5194/acp-14-1881-2014, 2014
C. D. Cappa, E. J. Williams, D. A. Lack, G. M. Buffaloe, D. Coffman, K. L. Hayden, S. C. Herndon, B. M. Lerner, S.-M. Li, P. Massoli, R. McLaren, I. Nuaaman, T. B. Onasch, and P. K. Quinn
Atmos. Chem. Phys., 14, 1337–1352, https://doi.org/10.5194/acp-14-1337-2014, https://doi.org/10.5194/acp-14-1337-2014, 2014
C. D. Cappa, X. Zhang, C. L. Loza, J. S. Craven, L. D. Yee, and J. H. Seinfeld
Atmos. Chem. Phys., 13, 1591–1606, https://doi.org/10.5194/acp-13-1591-2013, https://doi.org/10.5194/acp-13-1591-2013, 2013
Ryan C. Sullivan, David P. Billesbach, Sebastien Biraud, Stephen Chan, Richard Hart, Evan Keeler, Jenni Kyrouac, Sujan Pal, Mikhail Pekour, Sara L. Sullivan, Adam Theisen, Matt Tuftedal, and David R. Cook
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-168, https://doi.org/10.5194/essd-2025-168, 2025
Revised manuscript accepted for ESSD
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Turbulent fluxes quantify energy, water, or trace gases exchange into and out of the atmosphere. The US Department of Energy Atmospheric Radiation Measurement user facility has been making atmospheric measurements since the early 1990's, including of turbulent fluxes using two well-established methods: energy balance Bowen ratio and eddy covariance. This manuscript documents key aspects of these datasets, including their history, changes through time, and best use practices.
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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Kathryn A. Moore, Thomas C. J. Hill, Chamika K. Madawala, Raymond J. Leibensperger III, Samantha Greeney, Christopher D. Cappa, M. Dale Stokes, Grant B. Deane, Christopher Lee, Alexei V. Tivanski, Kimberly A. Prather, and Paul J. DeMott
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This article presents results from the first study in a new wind–wave channel at the Scripps Institution of Oceanography. The experiment tested how wind over the ocean surface influences production of sea spray particles, which are important for radiative forcing and cloud formation in the atmosphere. We found that particle concentration and chemical composition varied with wind speed and that variations were driven by changes in wind and wave breaking rather than seawater biology or chemistry.
Raghavendra Krishnamurthy, Rob K. Newsom, Colleen M. Kaul, Stefano Letizia, Mikhail Pekour, Nicholas Hamilton, Duli Chand, Donna Flynn, Nicola Bodini, and Patrick Moriarty
Wind Energ. Sci., 10, 361–380, https://doi.org/10.5194/wes-10-361-2025, https://doi.org/10.5194/wes-10-361-2025, 2025
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This study examines how atmospheric phenomena affect the recovery of wind farm wake – the disturbed air behind turbines. In regions like Oklahoma, where wind farms are often clustered, understanding wake recovery is crucial. We found that wind farms can alter phenomena like low-level jets, which are common in Oklahoma, by deflecting them above the wind farm. As a result, the impact of wakes can be observed up to 1–2 km above ground level.
Jerome D. Fast, Adam C. Varble, Fan Mei, Mikhail Pekour, Jason Tomlinson, Alla Zelenyuk, Art J. Sedlacek III, Maria Zawadowicz, and Louisa Emmons
Atmos. Chem. Phys., 24, 13477–13502, https://doi.org/10.5194/acp-24-13477-2024, https://doi.org/10.5194/acp-24-13477-2024, 2024
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Aerosol property measurements recently collected on the ground and by a research aircraft in central Argentina during the Cloud, Aerosol, and Complex Terrain Interactions (CACTI) campaign exhibit large spatial and temporal variability. These measurements coupled with coincident meteorological information provide a valuable data set needed to evaluate and improve model predictions of aerosols in a traditionally data-sparse region of South America.
Fan Mei, Jennifer M. Comstock, Mikhail S. Pekour, Jerome D. Fast, Krista L. Gaustad, Beat Schmid, Shuaiqi Tang, Damao Zhang, John E. Shilling, Jason M. Tomlinson, Adam C. Varble, Jian Wang, L. Ruby Leung, Lawrence Kleinman, Scot Martin, Sebastien C. Biraud, Brian D. Ermold, and Kenneth W. Burk
Earth Syst. Sci. Data, 16, 5429–5448, https://doi.org/10.5194/essd-16-5429-2024, https://doi.org/10.5194/essd-16-5429-2024, 2024
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Our study explores a comprehensive dataset from airborne field studies (2013–2018) conducted using the US Department of Energy's Gulfstream 1 (G-1). The 236 flights span diverse regions, including the Arctic, US Southern Great Plains, US West Coast, eastern North Atlantic, Amazon Basin in Brazil, and Sierras de Córdoba range in Argentina. This dataset provides unique insights into atmospheric dynamics, aerosols, and clouds and makes data available in a more accessible format.
Aliza Abraham, Matteo Puccioni, Arianna Jordan, Emina Maric, Nicola Bodini, Nicholas Hamilton, Stefano Letizia, Petra M. Klein, Elizabeth Smith, Sonia Wharton, Jonathan Gero, Jamey D. Jacob, Raghavendra Krishnamurthy, Rob K. Newsom, Mikhail Pekour, and Patrick Moriarty
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-148, https://doi.org/10.5194/wes-2024-148, 2024
Revised manuscript accepted for WES
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This study is the first to use real-world atmospheric measurements to show that large wind plants can increase the height of the planetary boundary layer, the part of the atmosphere near the surface where life takes place. The planetary boundary layer height governs processes like pollutant transport and cloud formation, and is a key parameter for modeling the atmosphere. The results of this study provide important insights into interactions between wind plants and their local environment.
Jianzhong Xu, Xinghua Zhang, Wenhui Zhao, Lixiang Zhai, Miao Zhong, Jinsen Shi, Junying Sun, Yanmei Liu, Conghui Xie, Yulong Tan, Kemei Li, Xinlei Ge, Qi Zhang, and Shichang Kang
Earth Syst. Sci. Data, 16, 1875–1900, https://doi.org/10.5194/essd-16-1875-2024, https://doi.org/10.5194/essd-16-1875-2024, 2024
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A comprehensive aerosol observation project was carried out in the Tibetan Plateau (TP) and its surroundings in recent years to investigate the properties and sources of atmospheric aerosols as well as their regional differences by performing multiple intensive field observations. The release of this dataset can provide basic and systematic data for related research in the atmospheric, cryospheric, and environmental sciences in this unique region.
Ryan N. Farley, James E. Lee, Laura-Hélèna Rivellini, Alex K. Y. Lee, Rachael Dal Porto, Christopher D. Cappa, Kyle Gorkowski, Abu Sayeed Md Shawon, Katherine B. Benedict, Allison C. Aiken, Manvendra K. Dubey, and Qi Zhang
Atmos. Chem. Phys., 24, 3953–3971, https://doi.org/10.5194/acp-24-3953-2024, https://doi.org/10.5194/acp-24-3953-2024, 2024
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The black carbon aerosol composition and mixing state were characterized using a soot particle aerosol mass spectrometer. Single-particle measurements revealed the major role of atmospheric processing in modulating the black carbon mixing state. A significant fraction of soot particles were internally mixed with oxidized organic aerosol and sulfate, with implications for activation as cloud nuclei.
Lindsay M. Sheridan, Raghavendra Krishnamurthy, William I. Gustafson Jr., Ye Liu, Brian J. Gaudet, Nicola Bodini, Rob K. Newsom, and Mikhail Pekour
Wind Energ. Sci., 9, 741–758, https://doi.org/10.5194/wes-9-741-2024, https://doi.org/10.5194/wes-9-741-2024, 2024
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In 2020, lidar-mounted buoys owned by the US Department of Energy (DOE) were deployed off the California coast in two wind energy lease areas and provided valuable year-long analyses of offshore low-level jet (LLJ) characteristics at heights relevant to wind turbines. In addition to the LLJ climatology, this work provides validation of LLJ representation in atmospheric models that are essential for assessing the potential energy yield of offshore wind farms.
Jian Zhao, Valter Mickwitz, Yuanyuan Luo, Ella Häkkinen, Frans Graeffe, Jiangyi Zhang, Hilkka Timonen, Manjula Canagaratna, Jordan E. Krechmer, Qi Zhang, Markku Kulmala, Juha Kangasluoma, Douglas Worsnop, and Mikael Ehn
Atmos. Meas. Tech., 17, 1527–1543, https://doi.org/10.5194/amt-17-1527-2024, https://doi.org/10.5194/amt-17-1527-2024, 2024
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Organic aerosol constitutes a significant portion of atmospheric fine particles but is less characterized due to its vast number of constituents. Recently, we developed a system for online measurements of particle-phase highly oxygenated organic molecules (HOMs). In this work, we systematically characterized the system, developed a new unit to enhance its performance, and demonstrated the essential role of thermograms in inferring volatility and quantifying HOMs in organic aerosols.
Xinlei Ge, Yele Sun, Justin Trousdell, Mindong Chen, and Qi Zhang
Atmos. Meas. Tech., 17, 423–439, https://doi.org/10.5194/amt-17-423-2024, https://doi.org/10.5194/amt-17-423-2024, 2024
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This study aims to enhance the application of the Aerodyne high-resolution aerosol mass spectrometer (HR-AMS) in characterizing organic nitrogen (ON) species within aerosol particles and droplets. A thorough analysis was conducted on 75 ON standards that represent a diverse spectrum of ambient ON types. The results underscore the capacity of the HR-AMS in examining the concentration and chemistry of atmospheric ON compounds, thereby offering insights into their sources and environmental impacts.
Lan Ma, Reed Worland, Laura Heinlein, Chrystal Guzman, Wenqing Jiang, Christopher Niedek, Keith J. Bein, Qi Zhang, and Cort Anastasio
Atmos. Chem. Phys., 24, 1–21, https://doi.org/10.5194/acp-24-1-2024, https://doi.org/10.5194/acp-24-1-2024, 2024
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We measured concentrations of three photooxidants – the hydroxyl radical, triplet excited states of organic carbon, and singlet molecular oxygen – in fine particles collected over a year. Concentrations are highest in extracts of fresh biomass burning particles, largely because they have the highest particle concentrations and highest light absorption. When normalized by light absorption, rates of formation for each oxidant are generally similar for the four particle types we observed.
Ryan N. Farley, Sonya Collier, Christopher D. Cappa, Leah R. Williams, Timothy B. Onasch, Lynn M. Russell, Hwajin Kim, and Qi Zhang
Atmos. Chem. Phys., 23, 15039–15056, https://doi.org/10.5194/acp-23-15039-2023, https://doi.org/10.5194/acp-23-15039-2023, 2023
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Soot particles, also known as black carbon (BC), have important implications for global climate and regional air quality. After the particles are emitted, BC can be coated with other material, impacting the aerosol properties. We selectively measured the composition of particles containing BC to explore their sources and chemical transformations in the atmosphere. We focus on a persistent, multiday fog event in order to study the effects of chemical reactions occurring within liquid droplets.
Shuaiqi Tang, Adam C. Varble, Jerome D. Fast, Kai Zhang, Peng Wu, Xiquan Dong, Fan Mei, Mikhail Pekour, Joseph C. Hardin, and Po-Lun Ma
Geosci. Model Dev., 16, 6355–6376, https://doi.org/10.5194/gmd-16-6355-2023, https://doi.org/10.5194/gmd-16-6355-2023, 2023
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To assess the ability of Earth system model (ESM) predictions, we developed a tool called ESMAC Diags to understand how aerosols, clouds, and aerosol–cloud interactions are represented in ESMs. This paper describes its version 2 functionality. We compared the model predictions with measurements taken by planes, ships, satellites, and ground instruments over four regions across the world. Results show that this new tool can help identify model problems and guide future development of ESMs.
Lan Ma, Reed Worland, Wenqing Jiang, Christopher Niedek, Chrystal Guzman, Keith J. Bein, Qi Zhang, and Cort Anastasio
Atmos. Chem. Phys., 23, 8805–8821, https://doi.org/10.5194/acp-23-8805-2023, https://doi.org/10.5194/acp-23-8805-2023, 2023
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Although photooxidants are important in airborne particles, little is known of their concentrations. By measuring oxidants in a series of particle dilutions, we predict their concentrations in aerosol liquid water (ALW). We find •OH concentrations in ALW are on the order of 10−15 M, similar to their cloud/fog values, while oxidizing triplet excited states and singlet molecular oxygen have ALW values of ca. 10−13 M and 10−12 M, respectively, roughly 10–100 times higher than in cloud/fog drops.
Kevin J. Nihill, Matthew M. Coggon, Christopher Y. Lim, Abigail R. Koss, Bin Yuan, Jordan E. Krechmer, Kanako Sekimoto, Jose L. Jimenez, Joost de Gouw, Christopher D. Cappa, Colette L. Heald, Carsten Warneke, and Jesse H. Kroll
Atmos. Chem. Phys., 23, 7887–7899, https://doi.org/10.5194/acp-23-7887-2023, https://doi.org/10.5194/acp-23-7887-2023, 2023
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In this work, we collect emissions from controlled burns of biomass fuels that can be found in the western United States into an environmental chamber in order to simulate their oxidation as they pass through the atmosphere. These findings provide a detailed characterization of the composition of the atmosphere downwind of wildfires. In turn, this will help to explore the effects of these changing emissions on downwind populations and will also directly inform atmospheric and climate models.
Wenqing Jiang, Christopher Niedek, Cort Anastasio, and Qi Zhang
Atmos. Chem. Phys., 23, 7103–7120, https://doi.org/10.5194/acp-23-7103-2023, https://doi.org/10.5194/acp-23-7103-2023, 2023
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We studied how aqueous-phase secondary organic aerosol (aqSOA) form and evolve from a phenolic carbonyl commonly present in biomass burning smoke. The composition and optical properties of the aqSOA are significantly affected by photochemical reactions and are dependent on the oxidants' concentration and identity in water. During photoaging, the aqSOA initially becomes darker, but prolonged aging leads to the formation of volatile products, resulting in significant mass loss and photobleaching.
Nathaniel W. May, Noah Bernays, Ryan Farley, Qi Zhang, and Daniel A. Jaffe
Atmos. Chem. Phys., 23, 2747–2764, https://doi.org/10.5194/acp-23-2747-2023, https://doi.org/10.5194/acp-23-2747-2023, 2023
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In summer 2019 at Mt. Bachelor Observatory, we observed smoke from wildfires with transport times ranging from less than a day up to 2 weeks. Aerosol absorption of multi-day transported smoke was dominated by black carbon, while smoke with shorter transport times had greater brown carbon absorption. Notably, Siberian smoke exhibited aerosol scattering and physical properties indicative of contributions from larger particles than typically observed in smoke.
Christopher R. Niedek, Fan Mei, Maria A. Zawadowicz, Zihua Zhu, Beat Schmid, and Qi Zhang
Atmos. Meas. Tech., 16, 955–968, https://doi.org/10.5194/amt-16-955-2023, https://doi.org/10.5194/amt-16-955-2023, 2023
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This novel micronebulization aerosol mass spectrometry (MS) technique requires a low sample volume (10 μL) and can quantify nanogram levels of organic and inorganic particulate matter (PM) components when used with 34SO4. This technique was successfully applied to PM samples collected from uncrewed atmospheric measurement platforms and provided chemical information that agrees well with real-time data from a co-located aerosol chemical speciation monitor and offline data from secondary ion MS.
Siegfried Schobesberger, Emma L. D'Ambro, Lejish Vettikkat, Ben H. Lee, Qiaoyun Peng, David M. Bell, John E. Shilling, Manish Shrivastava, Mikhail Pekour, Jerome Fast, and Joel A. Thornton
Atmos. Meas. Tech., 16, 247–271, https://doi.org/10.5194/amt-16-247-2023, https://doi.org/10.5194/amt-16-247-2023, 2023
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We present a new, highly sensitive technique for measuring atmospheric ammonia, an important trace gas that is emitted mainly by agriculture. We deployed the instrument on an aircraft during research flights over rural Oklahoma. Due to its fast response, we could analyze correlations with turbulent winds and calculate ammonia emissions from nearby areas at 1 to 2 km resolution. We observed high spatial variability and point sources that are not resolved in the US National Emissions Inventory.
Lindsay M. Sheridan, Raghu Krishnamurthy, Gabriel García Medina, Brian J. Gaudet, William I. Gustafson Jr., Alicia M. Mahon, William J. Shaw, Rob K. Newsom, Mikhail Pekour, and Zhaoqing Yang
Wind Energ. Sci., 7, 2059–2084, https://doi.org/10.5194/wes-7-2059-2022, https://doi.org/10.5194/wes-7-2059-2022, 2022
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Using observations from lidar buoys, five reanalysis and analysis models that support the wind energy community are validated offshore and at rotor-level heights along the California Pacific coast. The models are found to underestimate the observed wind resource. Occasions of large model error occur in conjunction with stable atmospheric conditions, wind speeds associated with peak turbine power production, and mischaracterization of the diurnal wind speed cycle in summer months.
Jerome D. Fast, David M. Bell, Gourihar Kulkarni, Jiumeng Liu, Fan Mei, Georges Saliba, John E. Shilling, Kaitlyn Suski, Jason Tomlinson, Jian Wang, Rahul Zaveri, and Alla Zelenyuk
Atmos. Chem. Phys., 22, 11217–11238, https://doi.org/10.5194/acp-22-11217-2022, https://doi.org/10.5194/acp-22-11217-2022, 2022
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Recent aircraft measurements from the HI-SCALE campaign conducted over the Southern Great Plains (SGP) site in Oklahoma are used to quantify spatial variability of aerosol properties in terms of grid spacings typically used by weather and climate models. Surprisingly large horizontal gradients in aerosol properties were frequently observed in this rural area. This spatial variability can be used as an uncertainty range when comparing surface point measurements with model predictions.
Xueyin Ruan, Chun Zhao, Rahul A. Zaveri, Pengzhen He, Xinming Wang, Jingyuan Shao, and Lei Geng
Geosci. Model Dev., 15, 6143–6164, https://doi.org/10.5194/gmd-15-6143-2022, https://doi.org/10.5194/gmd-15-6143-2022, 2022
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Accurate prediction of aerosol pH in chemical transport models is essential to aerosol modeling. This study examines the performance of the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) on aerosol pH predictions and the sensitivities to emissions of nonvolatile cations and NH3, aerosol-phase state assumption, and heterogeneous sulfate production. Temporal evolution of aerosol pH during haze cycles in Beijing and the driving factors are also presented and discussed.
Fan Mei, Mikhail S. Pekour, Darielle Dexheimer, Gijs de Boer, RaeAnn Cook, Jason Tomlinson, Beat Schmid, Lexie A. Goldberger, Rob Newsom, and Jerome D. Fast
Earth Syst. Sci. Data, 14, 3423–3438, https://doi.org/10.5194/essd-14-3423-2022, https://doi.org/10.5194/essd-14-3423-2022, 2022
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This work focuses on an expanding number of data sets observed using ARM TBS (133 flights) and UAS (seven flights) platforms by the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) user facility. These data streams provide new perspectives on spatial variability of atmospheric and surface parameters, helping to address critical science questions in Earth system science research, such as the aerosol–cloud interaction in the boundary layer.
Xinghua Zhang, Wenhui Zhao, Lixiang Zhai, Miao Zhong, Jinsen Shi, Junying Sun, Yanmei Liu, Conghui Xie, Yulong Tan, Kemei Li, Xinlei Ge, Qi Zhang, Shichang Kang, and Jianzhong Xu
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-211, https://doi.org/10.5194/essd-2022-211, 2022
Manuscript not accepted for further review
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A comprehensive aerosol observation project was carried out in the Tibetan Plateau (TP) in recent years to investigate the properties and sources of atmospheric aerosols as well as their regional differences by performing multiple short-term intensive field observations. The real-time online high-time-resolution (hourly) data of aerosol properties in the different TP region are integrated in a new dataset and can provide supporting for related studies in in the TP.
Delaney B. Kilgour, Gordon A. Novak, Jon S. Sauer, Alexia N. Moore, Julie Dinasquet, Sarah Amiri, Emily B. Franklin, Kathryn Mayer, Margaux Winter, Clare K. Morris, Tyler Price, Francesca Malfatti, Daniel R. Crocker, Christopher Lee, Christopher D. Cappa, Allen H. Goldstein, Kimberly A. Prather, and Timothy H. Bertram
Atmos. Chem. Phys., 22, 1601–1613, https://doi.org/10.5194/acp-22-1601-2022, https://doi.org/10.5194/acp-22-1601-2022, 2022
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We report measurements of gas-phase volatile organosulfur molecules made during a mesocosm phytoplankton bloom experiment. Dimethyl sulfide (DMS), methanethiol (MeSH), and benzothiazole accounted for on average over 90 % of total gas-phase sulfur emissions. This work focuses on factors controlling the production and emission of DMS and MeSH and the role of non-DMS molecules (such as MeSH and benzothiazole) in secondary sulfate formation in coastal marine environments.
Ka Ming Fung, Colette L. Heald, Jesse H. Kroll, Siyuan Wang, Duseong S. Jo, Andrew Gettelman, Zheng Lu, Xiaohong Liu, Rahul A. Zaveri, Eric C. Apel, Donald R. Blake, Jose-Luis Jimenez, Pedro Campuzano-Jost, Patrick R. Veres, Timothy S. Bates, John E. Shilling, and Maria Zawadowicz
Atmos. Chem. Phys., 22, 1549–1573, https://doi.org/10.5194/acp-22-1549-2022, https://doi.org/10.5194/acp-22-1549-2022, 2022
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Understanding the natural aerosol burden in the preindustrial era is crucial for us to assess how atmospheric aerosols affect the Earth's radiative budgets. Our study explores how a detailed description of dimethyl sulfide (DMS) oxidation (implemented in the Community Atmospheric Model version 6 with chemistry, CAM6-chem) could help us better estimate the present-day and preindustrial concentrations of sulfate and other relevant chemicals, as well as the resulting aerosol radiative impacts.
Fan Mei, Steven Spielman, Susanne Hering, Jian Wang, Mikhail S. Pekour, Gregory Lewis, Beat Schmid, Jason Tomlinson, and Maynard Havlicek
Atmos. Meas. Tech., 14, 7329–7340, https://doi.org/10.5194/amt-14-7329-2021, https://doi.org/10.5194/amt-14-7329-2021, 2021
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This study focuses on understanding a versatile water-based condensation particle counter (vWCPC 3789) performance under various ambient pressure conditions (500–1000 hPa). A vWCPC has the advantage of avoiding health and safety concerns. However, its performance characterization under low pressure is rare but crucial for ensuring successful airborne deployment. This paper provides advanced knowledge of operating a vWCPC 3789 to capture the spatial variations of atmospheric aerosols.
Fan Mei, Jian Wang, Shan Zhou, Qi Zhang, Sonya Collier, and Jianzhong Xu
Atmos. Chem. Phys., 21, 13019–13029, https://doi.org/10.5194/acp-21-13019-2021, https://doi.org/10.5194/acp-21-13019-2021, 2021
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This work focuses on understanding aerosol's ability to act as cloud condensation nuclei (CCN) and its variations with organic oxidation level and volatility using measurements at a rural site. Aerosol properties were examined from four air mass sources. The results help improve the accurate representation of aerosol from different ambient aerosol emissions, transformation pathways, and atmospheric processes in a climate model.
Maria A. Zawadowicz, Kaitlyn Suski, Jiumeng Liu, Mikhail Pekour, Jerome Fast, Fan Mei, Arthur J. Sedlacek, Stephen Springston, Yang Wang, Rahul A. Zaveri, Robert Wood, Jian Wang, and John E. Shilling
Atmos. Chem. Phys., 21, 7983–8002, https://doi.org/10.5194/acp-21-7983-2021, https://doi.org/10.5194/acp-21-7983-2021, 2021
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This paper describes the results of a recent field campaign in the eastern North Atlantic, where two mass spectrometers were deployed aboard a research aircraft to measure the chemistry of aerosols and trace gases. Very clean conditions were found, dominated by local sulfate-rich acidic aerosol and very aged organics. Evidence of
long-range transport of aerosols from the continents was also identified.
Xiaolu Zhang, Krystyna Trzepla, Warren White, Sean Raffuse, and Nicole Pauly Hyslop
Atmos. Meas. Tech., 14, 3217–3231, https://doi.org/10.5194/amt-14-3217-2021, https://doi.org/10.5194/amt-14-3217-2021, 2021
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Three models of carbon analyzer were used in the past decade to measure carbonaceous particles from samples collected within the Chemical Speciation Network. This study compares results from these analyzer models to investigate the impact on long-term data from instrument differences. Good agreement was found among the three models for total carbon, organic carbon, and elemental carbon, while the reasons for and implications of some notable differences in their subtractions are investigated.
Duseong S. Jo, Alma Hodzic, Louisa K. Emmons, Simone Tilmes, Rebecca H. Schwantes, Michael J. Mills, Pedro Campuzano-Jost, Weiwei Hu, Rahul A. Zaveri, Richard C. Easter, Balwinder Singh, Zheng Lu, Christiane Schulz, Johannes Schneider, John E. Shilling, Armin Wisthaler, and Jose L. Jimenez
Atmos. Chem. Phys., 21, 3395–3425, https://doi.org/10.5194/acp-21-3395-2021, https://doi.org/10.5194/acp-21-3395-2021, 2021
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Secondary organic aerosol (SOA) is a major component of submicron particulate matter, but there are a lot of uncertainties in the future prediction of SOA. We used CESM 2.1 to investigate future IEPOX SOA concentration changes. The explicit chemistry predicted substantial changes in IEPOX SOA depending on the future scenario, but the parameterization predicted weak changes due to simplified chemistry, which shows the importance of correct physicochemical dependencies in future SOA prediction.
Junfeng Wang, Jianhuai Ye, Dantong Liu, Yangzhou Wu, Jian Zhao, Weiqi Xu, Conghui Xie, Fuzhen Shen, Jie Zhang, Paul E. Ohno, Yiming Qin, Xiuyong Zhao, Scot T. Martin, Alex K. Y. Lee, Pingqing Fu, Daniel J. Jacob, Qi Zhang, Yele Sun, Mindong Chen, and Xinlei Ge
Atmos. Chem. Phys., 20, 14091–14102, https://doi.org/10.5194/acp-20-14091-2020, https://doi.org/10.5194/acp-20-14091-2020, 2020
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We compared the organics in total submicron matter and those coated on BC cores during summertime in Beijing and found large differences between them. Traffic-related OA was associated significantly with BC, while cooking-related OA did not coat BC. In addition, a factor likely originated from primary biomass burning OA was only identified in BC-containing particles. Such a unique BBOA requires further field and laboratory studies to verify its presence and elucidate its properties and impacts.
Lawrence I. Kleinman, Arthur J. Sedlacek III, Kouji Adachi, Peter R. Buseck, Sonya Collier, Manvendra K. Dubey, Anna L. Hodshire, Ernie Lewis, Timothy B. Onasch, Jeffery R. Pierce, John Shilling, Stephen R. Springston, Jian Wang, Qi Zhang, Shan Zhou, and Robert J. Yokelson
Atmos. Chem. Phys., 20, 13319–13341, https://doi.org/10.5194/acp-20-13319-2020, https://doi.org/10.5194/acp-20-13319-2020, 2020
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Aerosols from wildfires affect the Earth's temperature by absorbing light or reflecting it back into space. This study investigates time-dependent chemical, microphysical, and optical properties of aerosols generated by wildfires in the Pacific Northwest, USA. Wildfire smoke plumes were traversed by an instrumented aircraft at locations near the fire and up to 3.5 h travel time downwind. Although there was no net aerosol production, aerosol particles grew and became more efficient scatters.
Hwajin Kim, Qi Zhang, and Yele Sun
Atmos. Chem. Phys., 20, 11527–11550, https://doi.org/10.5194/acp-20-11527-2020, https://doi.org/10.5194/acp-20-11527-2020, 2020
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Severe spring haze and influences of long-range transport in the Seoul metropolitan area (SMA) in March 2019 were investigated. Simultaneous downwind (SMA) and upwind (Beijing) measurements using AMS and ACSM over the same period showed that PM species can be transported in approximately 2 d. Nitrate was the most responsible, and sulfate and two regional-transport-influenced SOAs also contributed. Enhancement of Pb also showed that the haze in the SMA was influenced by the regional transport.
Christopher D. Cappa, Christopher Y. Lim, David H. Hagan, Matthew Coggon, Abigail Koss, Kanako Sekimoto, Joost de Gouw, Timothy B. Onasch, Carsten Warneke, and Jesse H. Kroll
Atmos. Chem. Phys., 20, 8511–8532, https://doi.org/10.5194/acp-20-8511-2020, https://doi.org/10.5194/acp-20-8511-2020, 2020
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Smoke from combustion of a wide range of biomass fuels (e.g., leaves, twigs, logs, peat, and dung) was photochemically aged in a small chamber for up to 8 d of equivalent atmospheric aging. Upon aging, the particle chemical composition and ability to absorb sunlight changed owing to reactions in both the gas and particulate phases. We developed a model to explain the observations and used this to derive insights into the aging of smoke in the atmosphere.
Jianjun Li, Qi Zhang, Gehui Wang, Jin Li, Can Wu, Lang Liu, Jiayuan Wang, Wenqing Jiang, Lijuan Li, Kin Fai Ho, and Junji Cao
Atmos. Chem. Phys., 20, 4889–4904, https://doi.org/10.5194/acp-20-4889-2020, https://doi.org/10.5194/acp-20-4889-2020, 2020
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We examined light absorption properties and molecular composition of water-soluble (WS) and water-insoluble (WI) BrC in PM2.5 collected from northwest China. We found that photochemical formation contributes significantly to light absorption of WI-BrC in summer, whereas aqueous-phase reactions play an important role in secondary WS-BrC formation in winter. BrC was estimated to account for 1.36 % and 3.74 %, respectively, of total down-welling solar radiation in the UV range in summer and winter.
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.
Ziyue Li, Emma L. D'Ambro, Siegfried Schobesberger, Cassandra J. Gaston, Felipe D. Lopez-Hilfiker, Jiumeng Liu, John E. Shilling, Joel A. Thornton, and Christopher D. Cappa
Atmos. Chem. Phys., 20, 2489–2512, https://doi.org/10.5194/acp-20-2489-2020, https://doi.org/10.5194/acp-20-2489-2020, 2020
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We discuss the development and application of a robust clustering method for the interpretation of compound-specific organic aerosol thermal desorption profiles. We demonstrate the utility of clustering for analysis and interpretation of the composition and volatility of secondary organic aerosol. We show that the thermal desorption profiles are represented by only 9–13 distinct clusters, with the number of clusters obtained dependent on the precursor and formation conditions.
Fan Mei, Jian Wang, Jennifer M. Comstock, Ralf Weigel, Martina Krämer, Christoph Mahnke, John E. Shilling, Johannes Schneider, Christiane Schulz, Charles N. Long, Manfred Wendisch, Luiz A. T. Machado, Beat Schmid, Trismono Krisna, Mikhail Pekour, John Hubbe, Andreas Giez, Bernadett Weinzierl, Martin Zoeger, Mira L. Pöhlker, Hans Schlager, Micael A. Cecchini, Meinrat O. Andreae, Scot T. Martin, Suzane S. de Sá, Jiwen Fan, Jason Tomlinson, Stephen Springston, Ulrich Pöschl, Paulo Artaxo, Christopher Pöhlker, Thomas Klimach, Andreas Minikin, Armin Afchine, and Stephan Borrmann
Atmos. Meas. Tech., 13, 661–684, https://doi.org/10.5194/amt-13-661-2020, https://doi.org/10.5194/amt-13-661-2020, 2020
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In 2014, the US DOE G1 aircraft and the German HALO aircraft overflew the Amazon basin to study how aerosols influence cloud cycles under a clean condition and around a tropical megacity. This paper describes how to meaningfully compare similar measurements from two research aircraft and identify the potential measurement issue. We also discuss the uncertainty range for each measurement for further usage in model evaluation and satellite data validation.
Crystal D. McClure, Christopher Y. Lim, David H. Hagan, Jesse H. Kroll, and Christopher D. Cappa
Atmos. Chem. Phys., 20, 1531–1547, https://doi.org/10.5194/acp-20-1531-2020, https://doi.org/10.5194/acp-20-1531-2020, 2020
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We characterized various optical, chemical, and physical properties of particles produced from combustion of a variety of different biomass fuels, many representative of those found in the western US. We find that many properties scale with the ratio between bulk average organic aerosol and black carbon mass concentrations, although there are some properties that do not.
Matthew M. Coggon, Christopher Y. Lim, Abigail R. Koss, Kanako Sekimoto, Bin Yuan, Jessica B. Gilman, David H. Hagan, Vanessa Selimovic, Kyle J. Zarzana, Steven S. Brown, James M. Roberts, Markus Müller, Robert Yokelson, Armin Wisthaler, Jordan E. Krechmer, Jose L. Jimenez, Christopher Cappa, Jesse H. Kroll, Joost de Gouw, and Carsten Warneke
Atmos. Chem. Phys., 19, 14875–14899, https://doi.org/10.5194/acp-19-14875-2019, https://doi.org/10.5194/acp-19-14875-2019, 2019
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Wildfire emissions significantly contribute to adverse air quality; however, the chemical processes that lead to hazardous pollutants, such as ozone, are not fully understood. In this study, we describe laboratory experiments where we simulate the atmospheric chemistry of smoke emitted from a range of biomass fuels. We show that certain understudied compounds, such as furans and phenolic compounds, are significant contributors to pollutants formed as a result of typical atmospheric oxidation.
Laura Bianco, Irina V. Djalalova, James M. Wilczak, Joseph B. Olson, Jaymes S. Kenyon, Aditya Choukulkar, Larry K. Berg, Harindra J. S. Fernando, Eric P. Grimit, Raghavendra Krishnamurthy, Julie K. Lundquist, Paytsar Muradyan, Mikhail Pekour, Yelena Pichugina, Mark T. Stoelinga, and David D. Turner
Geosci. Model Dev., 12, 4803–4821, https://doi.org/10.5194/gmd-12-4803-2019, https://doi.org/10.5194/gmd-12-4803-2019, 2019
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During the second Wind Forecast Improvement Project, improvements to the parameterizations were applied to the High Resolution Rapid Refresh model and its nested version. The impacts of the new parameterizations on the forecast of 80 m wind speeds and power are assessed, using sodars and profiling lidars observations for comparison. Improvements are evaluated as a function of the model’s initialization time, forecast horizon, time of the day, season, site elevation, and meteorological phenomena.
Christopher Y. Lim, David H. Hagan, Matthew M. Coggon, Abigail R. Koss, Kanako Sekimoto, Joost de Gouw, Carsten Warneke, Christopher D. Cappa, and Jesse H. Kroll
Atmos. Chem. Phys., 19, 12797–12809, https://doi.org/10.5194/acp-19-12797-2019, https://doi.org/10.5194/acp-19-12797-2019, 2019
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Wildfires are a large source of gases and particles to the atmosphere, both of which impact human health and climate. The amount and composition of particles from wildfires can change with time in the atmosphere; however, the impact of aging is not well understood. In a series of controlled laboratory experiments, we show that the particles are oxidized and a significant fraction of the gas-phase carbon (24 %–56 %) is converted to particle mass over the course of several days in the atmosphere.
Emma L. D'Ambro, Siegfried Schobesberger, Cassandra J. Gaston, Felipe D. Lopez-Hilfiker, Ben H. Lee, Jiumeng Liu, Alla Zelenyuk, David Bell, Christopher D. Cappa, Taylor Helgestad, Ziyue Li, Alex Guenther, Jian Wang, Matthew Wise, Ryan Caylor, Jason D. Surratt, Theran Riedel, Noora Hyttinen, Vili-Taneli Salo, Galib Hasan, Theo Kurtén, John E. Shilling, and Joel A. Thornton
Atmos. Chem. Phys., 19, 11253–11265, https://doi.org/10.5194/acp-19-11253-2019, https://doi.org/10.5194/acp-19-11253-2019, 2019
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Isoprene is the most abundantly emitted reactive organic gas globally, and thus it is important to understand its fate and role in aerosol formation and growth. A major product of its oxidation is an epoxydiol, IEPOX, which can be efficiently taken up by acidic aerosol to generate substantial amounts of secondary organic aerosol (SOA). We present chamber experiments exploring the properties of IEPOX SOA and reconcile discrepancies between field, laboratory, and model studies of this process.
Jianjun Li, Gehui Wang, Qi Zhang, Jin Li, Can Wu, Wenqing Jiang, Tong Zhu, and Limin Zeng
Atmos. Chem. Phys., 19, 10481–10496, https://doi.org/10.5194/acp-19-10481-2019, https://doi.org/10.5194/acp-19-10481-2019, 2019
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In this study, we investigated molecular compositions of organic aerosols (OAs) in summertime PM2.5 at a rural site in the North China Plain. We found that regional emission from field biomass burning (BB) significantly affects the concentration and molecular distribution of aliphatic lipids, sugars, and terpene-derived SOA, but has limited influence on PAHs, hopenes, and phthalates. The contribution of BB to OA increased by more than 50 % during the period influenced by regional open-field BB.
Ingeborg E. Nielsen, Henrik Skov, Andreas Massling, Axel C. Eriksson, Manuel Dall'Osto, Heikki Junninen, Nina Sarnela, Robert Lange, Sonya Collier, Qi Zhang, Christopher D. Cappa, and Jacob K. Nøjgaard
Atmos. Chem. Phys., 19, 10239–10256, https://doi.org/10.5194/acp-19-10239-2019, https://doi.org/10.5194/acp-19-10239-2019, 2019
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Measurements of the chemical composition of sub-micrometer aerosols were carried out in northern Greenland during the Arctic haze (February–May) where concentrations are high due to favorable conditions for long-range transport. Sulfate was the dominant aerosol (66 %), followed by organic matter (24 %). The highest black carbon concentrations where observed in February. Source apportionment yielded three factors: a primary factor (12 %), an Arctic haze factor (64 %) and a marine factor (22 %).
Weiqi Xu, Conghui Xie, Eleni Karnezi, Qi Zhang, Junfeng Wang, Spyros N. Pandis, Xinlei Ge, Jingwei Zhang, Junling An, Qingqing Wang, Jian Zhao, Wei Du, Yanmei Qiu, Wei Zhou, Yao He, Ying Li, Jie Li, Pingqing Fu, Zifa Wang, Douglas R. Worsnop, and Yele Sun
Atmos. Chem. Phys., 19, 10205–10216, https://doi.org/10.5194/acp-19-10205-2019, https://doi.org/10.5194/acp-19-10205-2019, 2019
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We present the first aerosol volatility measurements in Beijing in summer using a thermodenuder coupled with aerosol mass spectrometers. Our results showed that organic aerosol (OA) comprised mainly semi-volatile organic compounds in summer, and the freshly oxidized secondary OA was the most volatile component. We also found quite different volatility distributions in black-carbon-containing primary and secondary OA, ambient OA, ambient secondary OA and the WRF-Chem model.
Xinghua Zhang, Jianzhong Xu, Shichang Kang, Qi Zhang, and Junying Sun
Atmos. Chem. Phys., 19, 7897–7911, https://doi.org/10.5194/acp-19-7897-2019, https://doi.org/10.5194/acp-19-7897-2019, 2019
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Highly time resolved chemistry and sources of PM1 were measured by an Aerodyne HR-ToF-AMS at Waliguan Baseline Observatory, a high-altitude background station at the northeastern edge of Qinghai–Tibet Plateau (QTP), during summer 2017. Relatively higher mass concentration of PM1 and dominant sulfate contribution were observed in this site compared to those at other high-elevation sites in the southern or central QTP, indicating the different aerosol sources between them.
Richie Kaur, Jacqueline R. Labins, Scarlett S. Helbock, Wenqing Jiang, Keith J. Bein, Qi Zhang, and Cort Anastasio
Atmos. Chem. Phys., 19, 6579–6594, https://doi.org/10.5194/acp-19-6579-2019, https://doi.org/10.5194/acp-19-6579-2019, 2019
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We measured hydroxyl radical (•OH), singlet oxygen (1O2*), and organic triplets (3C*) in illuminated aqueous particle extracts. After measuring the impact of dilution on oxidant concentrations, we extrapolated our results to predict them in ambient particles – 1O2* and 3C* concentrations appear to be greatly enhanced, while •OH appears largely unchanged. Two of these oxidants (1O2*, 3C*) are not yet included in atmospheric models, and our results make it possible to include them in the future.
Ali Akherati, Christopher D. Cappa, Michael J. Kleeman, Kenneth S. Docherty, Jose L. Jimenez, Stephen M. Griffith, Sebastien Dusanter, Philip S. Stevens, and Shantanu H. Jathar
Atmos. Chem. Phys., 19, 4561–4594, https://doi.org/10.5194/acp-19-4561-2019, https://doi.org/10.5194/acp-19-4561-2019, 2019
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Unburned and partially burned organic compounds emitted from fossil fuel and biomass combustion can react in the atmosphere in the presence of sunlight to form particles. In this work, we use an air pollution model to examine the influence of these organic compounds released by motor vehicles and fires on fine particle pollution in southern California.
Nicola Bodini, Julie K. Lundquist, Raghavendra Krishnamurthy, Mikhail Pekour, Larry K. Berg, and Aditya Choukulkar
Atmos. Chem. Phys., 19, 4367–4382, https://doi.org/10.5194/acp-19-4367-2019, https://doi.org/10.5194/acp-19-4367-2019, 2019
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To improve the parameterization of the turbulence dissipation rate (ε) in numerical weather prediction models, we have assessed its temporal and spatial variability at various scales in the Columbia River Gorge during the WFIP2 field experiment. The turbulence dissipation rate shows large spatial variability, even at the microscale, with larger values in sites located downwind of complex orographic structures or in wind farm wakes. Distinct diurnal and seasonal cycles in ε have also been found.
Shan Zhou, Sonya Collier, Daniel A. Jaffe, and Qi Zhang
Atmos. Chem. Phys., 19, 1571–1585, https://doi.org/10.5194/acp-19-1571-2019, https://doi.org/10.5194/acp-19-1571-2019, 2019
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Regional background aerosols in the western US were studied from a mountaintop observatory during summer. Oxygenated organics and sulfate were dominant aerosol components. However, free tropospheric aerosols were more enriched in sulfate, frequently acidic, and comprised mainly of highly oxidized low-volatility organic species. In contrast, organic aerosols in the boundary-layer-influenced air masses were less oxidized and appeared to be semivolatile.
Jian Wang, John E. Shilling, Jiumeng Liu, Alla Zelenyuk, David M. Bell, Markus D. Petters, Ryan Thalman, Fan Mei, Rahul A. Zaveri, and Guangjie Zheng
Atmos. Chem. Phys., 19, 941–954, https://doi.org/10.5194/acp-19-941-2019, https://doi.org/10.5194/acp-19-941-2019, 2019
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Earlier studies showed organic hygroscopicity increases with oxidation level. Such increases have been attributed to higher water solubility for more oxidized organics. By systematically varying the water content of activating droplets, we show that for secondary organic aerosols, essentially all organics are dissolved at the point of droplet activation. Therefore, the organic hygroscopicity is not limited by solubility but is dictated mainly by the molecular weight of organic species.
Peng Sun, Wei Nie, Xuguang Chi, Yuning Xie, Xin Huang, Zheng Xu, Ximeng Qi, Zhengning Xu, Lei Wang, Tianyi Wang, Qi Zhang, and Aijun Ding
Atmos. Chem. Phys., 18, 17177–17190, https://doi.org/10.5194/acp-18-17177-2018, https://doi.org/10.5194/acp-18-17177-2018, 2018
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A total of 2 years of online measurement of particulate nitrate was conducted at the SORPES station in the western Yangtze River Delta, eastern China. Nitrate was found to be the major driver of haze pollution and behaved differently in different seasons. In summer, thermodynamic equilibrium and photochemical processes controlled nitrate formation. In winter, N2O5 hydrolysis was demonstrated to be a major contributor to the nitrate episodes.
Ziyue Li, Katherine A. Smith, and Christopher D. Cappa
Atmos. Chem. Phys., 18, 14585–14608, https://doi.org/10.5194/acp-18-14585-2018, https://doi.org/10.5194/acp-18-14585-2018, 2018
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We investigated the influence of relative humidity (RH) on the heterogeneous oxidation of secondary organic aerosol (SOA) particles by OH radicals. We observed significantly faster volume loss and compositional change of SOA at high RH, showing that viscosity differences determine compositional changes, but variability in either the uptake coefficient or the fragmentation probability are required to explain the difference in volume loss between low and high RH.
Sailaja Eluri, Christopher D. Cappa, Beth Friedman, Delphine K. Farmer, and Shantanu H. Jathar
Atmos. Chem. Phys., 18, 13813–13838, https://doi.org/10.5194/acp-18-13813-2018, https://doi.org/10.5194/acp-18-13813-2018, 2018
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As oxidation flow reactors (OFRs) are increasingly used to study aerosol formation and evolution in laboratory and field environments, there is a need to develop models that can be used to interpret OFR data. In this work, we evaluate two coupled chemistry and thermodynamic models to simulate secondary organic aerosol formation (SOA) from diluted diesel exhaust and explore the sources, pathways, and processes important to SOA formation.
Sara D. Forestieri, Taylor M. Helgestad, Andrew T. Lambe, Lindsay Renbaum-Wolff, Daniel A. Lack, Paola Massoli, Eben S. Cross, Manvendra K. Dubey, Claudio Mazzoleni, Jason S. Olfert, Arthur J. Sedlacek III, Andrew Freedman, Paul Davidovits, Timothy B. Onasch, and Christopher D. Cappa
Atmos. Chem. Phys., 18, 12141–12159, https://doi.org/10.5194/acp-18-12141-2018, https://doi.org/10.5194/acp-18-12141-2018, 2018
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We characterized optical properties of flame-derived black carbon particles and interpret our observations through the use of Mie theory and Rayleigh–Debye–Gans theory. We determined that the mass absorption coefficient is independent of particle collapse and use this to derive theory- and wavelength-specific refractive indices for black carbon (BC). We demonstrate the inadequacy of Mie theory and suggest an alternative approach for atmospheric models to better represent light absorption by BC.
Sara D. Forestieri, Sean M. Staudt, Thomas M. Kuborn, Katharine Faber, Christopher R. Ruehl, Timothy H. Bertram, and Christopher D. Cappa
Atmos. Chem. Phys., 18, 10985–11005, https://doi.org/10.5194/acp-18-10985-2018, https://doi.org/10.5194/acp-18-10985-2018, 2018
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Our work establishes how surface tension reduction influences droplet growth and activation of simple sea spray mimics (NaCl coated with fatty acids). Fatty acids can substantially reduce droplet surface tension near activation but have limited impact on activation. Coating of NaCl by palmitic acid (a wax) impedes water uptake, but this impedance is removed if oleic acid (a liquid) is mixed in. The properties that surface-active compounds need to impact activation are theoretically examined.
John E. Shilling, Mikhail S. Pekour, Edward C. Fortner, Paulo Artaxo, Suzane de Sá, John M. Hubbe, Karla M. Longo, Luiz A. T. Machado, Scot T. Martin, Stephen R. Springston, Jason Tomlinson, and Jian Wang
Atmos. Chem. Phys., 18, 10773–10797, https://doi.org/10.5194/acp-18-10773-2018, https://doi.org/10.5194/acp-18-10773-2018, 2018
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We report aircraft observations of the evolution of organic aerosol in the Manaus urban plume as it ages. We observe dynamic changes in the organic aerosol. The mean carbon oxidation state of the OA increases from −0.6 to −0.45. Hydrocarbon-like organic aerosol (HOA) mass is lost and is balanced out by formation of oxygenated organic aerosol (OOA). Because HOA loss is balanced by OOA formation, we observe little change in the net Δorg / ΔCO values with aging.
Yele Sun, Weiqi Xu, Qi Zhang, Qi Jiang, Francesco Canonaco, André S. H. Prévôt, Pingqing Fu, Jie Li, John Jayne, Douglas R. Worsnop, and Zifa Wang
Atmos. Chem. Phys., 18, 8469–8489, https://doi.org/10.5194/acp-18-8469-2018, https://doi.org/10.5194/acp-18-8469-2018, 2018
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We present a 2–year analysis of organic aerosol (OA) from highly time–resolved measurements by an aerosol chemical speciation monitor in the megacity of Beijing. The sources of OA were analyzed with the advanced factor analysis of a multilinear engine (ME-2). Our results showed very different seasonal patterns, relative humidity and temperature dependence, and sources regions among different OA factors. The sources and processes of OA factors, and their roles in haze pollution are elucidated.
Hwajin Kim, Qi Zhang, and Jongbae Heo
Atmos. Chem. Phys., 18, 7149–7168, https://doi.org/10.5194/acp-18-7149-2018, https://doi.org/10.5194/acp-18-7149-2018, 2018
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Aerosol chemistry, sources and processes driving the observed temporal and diurnal variations of PM were studied in the Seoul Metropolitan Area (SMA) during spring 2016. An in-depth analysis of the data uncovered that air quality in SMA was influenced strongly by secondary aerosol formation. Also, it was found that the haze episode during spring was mainly caused by a combination of both regional and local factors, which is different from the winter haze mainly caused by intense local sources.
Dean B. Atkinson, Mikhail Pekour, Duli Chand, James G. Radney, Katheryn R. Kolesar, Qi Zhang, Ari Setyan, Norman T. O'Neill, and Christopher D. Cappa
Atmos. Chem. Phys., 18, 5499–5514, https://doi.org/10.5194/acp-18-5499-2018, https://doi.org/10.5194/acp-18-5499-2018, 2018
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We use in situ measurements of particle light extinction to assess the performance of a typical aerosol remote retrieval method. The retrieved fine-mode fraction of extinction, a property commonly used to characterize the anthropogenic influence on the aerosol optical depth, compares well with the in situ measurements as does the retrieved effective fine-mode radius, which characterizes the average size of the particles that contribute most to scattering.
Xinghua Zhang, Jianzhong Xu, Shichang Kang, Yanmei Liu, and Qi Zhang
Atmos. Chem. Phys., 18, 4617–4638, https://doi.org/10.5194/acp-18-4617-2018, https://doi.org/10.5194/acp-18-4617-2018, 2018
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Highly time and chemically resolved submicron aerosol properties were characterized online for the first time in a high-altitude site (Qomolangma station, 4276 m a.s.l.) in the northern Himalayas by using the Aerodyne HR-ToF-AMS. Biomass burning plumes were frequently observed and the dynamic processes (emissions, transport, and chemical processing) were characterized. The source and chemical composition of organic aerosol were further elucidated using positive matrix factorization analysis.
Jianzhong Xu, Qi Zhang, Jinsen Shi, Xinlei Ge, Conghui Xie, Junfeng Wang, Shichang Kang, Ruixiong Zhang, and Yuhang Wang
Atmos. Chem. Phys., 18, 427–443, https://doi.org/10.5194/acp-18-427-2018, https://doi.org/10.5194/acp-18-427-2018, 2018
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This manuscript presents results from a comprehensive field study using an HR-AMS coupled with a suite of other instruments in central Tibetan Plateau. The study discusses the chemical composition, sources, and processes of submicron aerosol during the transition from pre-monsoon to monsoon. Organic aerosol was overall highly oxidized during the entire study with higher O / C ratios during the pre-monsoon period. Sensitivity of air pollution transport with synoptic process was also evaluated.
Alex K. Y. Lee, Chia-Li Chen, Jun Liu, Derek J. Price, Raghu Betha, Lynn M. Russell, Xiaolu Zhang, and Christopher D. Cappa
Atmos. Chem. Phys., 17, 15055–15067, https://doi.org/10.5194/acp-17-15055-2017, https://doi.org/10.5194/acp-17-15055-2017, 2017
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Understanding the mixing state of ambient black carbon (BC) and the chemical characteristics of its associated coatings is important to evaluate BC fate and environmental impacts. This study reports fresh secondary organic aerosol (SOA) formation near traffic emissions during daytime. Our observations suggest that BC was unlikely the major condensation sink of SOA, and a portion of SOA condensed on BC surface was chemically different from other SOA particles that were externally mixed with BC.
Gouri Prabhakar, Caroline L. Parworth, Xiaolu Zhang, Hwajin Kim, Dominique E. Young, Andreas J. Beyersdorf, Luke D. Ziemba, John B. Nowak, Timothy H. Bertram, Ian C. Faloona, Qi Zhang, and Christopher D. Cappa
Atmos. Chem. Phys., 17, 14747–14770, https://doi.org/10.5194/acp-17-14747-2017, https://doi.org/10.5194/acp-17-14747-2017, 2017
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This work assesses the processes that control the ambient concentrations of particulate nitrate in the the wintertime San Joaquin Valley of California through a combination of aircraft and surface measurements made during the DISCOVER-AQ study. We provide an observational demonstration of how nocturnal production and advection in aloft layers combines with daytime production and loss from entrainment and deposition to give rise to a distinct diurnal profile in surface nitrate concentrations.
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.
Matthew J. Gunsch, Rachel M. Kirpes, Katheryn R. Kolesar, Tate E. Barrett, Swarup China, Rebecca J. Sheesley, Alexander Laskin, Alfred Wiedensohler, Thomas Tuch, and Kerri A. Pratt
Atmos. Chem. Phys., 17, 10879–10892, https://doi.org/10.5194/acp-17-10879-2017, https://doi.org/10.5194/acp-17-10879-2017, 2017
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Arctic sea ice loss is leading to increasing petroleum extraction and shipping. It is necessary to identify emissions from these activities for improved Arctic air quality and climate assessment. Atmospheric particles were measured from August to September 2015 in Utqiaġvik, AK. For periods influenced by Prudhoe Bay, significant influence associated with combustion emissions was observed, compared to fresh sea spray influence during Arctic Ocean periods.
Simon O'Meara, David O. Topping, Rahul A. Zaveri, and Gordon McFiggans
Atmos. Chem. Phys., 17, 10477–10494, https://doi.org/10.5194/acp-17-10477-2017, https://doi.org/10.5194/acp-17-10477-2017, 2017
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To simulate particle-phase diffusion, an analytical expression is desired because it takes less calculation time than a differential equation. Here a correction is found for the analytical solution for when diffusivity is dependent on composition, thereby making it more widely applicable than before. Consequently, we are able to more realistically evaluate the rate limitation (if any) imposed by particle-phase diffusion on component partitioning between the gas and particle phase.
Jinghao Zhai, Xiaohui Lu, Ling Li, Qi Zhang, Ci Zhang, Hong Chen, Xin Yang, and Jianmin Chen
Atmos. Chem. Phys., 17, 7481–7493, https://doi.org/10.5194/acp-17-7481-2017, https://doi.org/10.5194/acp-17-7481-2017, 2017
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The effective density, chemical composition, and optical properties of particles produced by burning rice straw were measured. Density distribution and single-particle mass spectrometry showed the size-dependent external mixing of black carbon, organic carbon, and potassium salts in biomass burning particles. Optical measurements indicated the significant presence of brown carbon in all particles. Though freshly emitted, light absorption enhancement was observed for particles larger than 200 nm.
Jianlin Hu, Shantanu Jathar, Hongliang Zhang, Qi Ying, Shu-Hua Chen, Christopher D. Cappa, and Michael J. Kleeman
Atmos. Chem. Phys., 17, 5379–5391, https://doi.org/10.5194/acp-17-5379-2017, https://doi.org/10.5194/acp-17-5379-2017, 2017
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Organic aerosol is a major constituent of ultrafine particulate matter (PM0.1). In this study, a source-oriented air quality model was used to simulate the concentrations and sources of primary and secondary organic aerosols in PM0.1 in California for a 9-year modeling period to provide useful information for epidemiological studies to further investigate the associations with health outcomes.
Haiyan Li, Qi Zhang, Qiang Zhang, Chunrong Chen, Litao Wang, Zhe Wei, Shan Zhou, Caroline Parworth, Bo Zheng, Francesco Canonaco, André S. H. Prévôt, Ping Chen, Hongliang Zhang, Timothy J. Wallington, and Kebin He
Atmos. Chem. Phys., 17, 4751–4768, https://doi.org/10.5194/acp-17-4751-2017, https://doi.org/10.5194/acp-17-4751-2017, 2017
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The sources and aerosol evolution processes of severe pollution episodes were investigated in Handan during wintertime using real-time measurements. An in-depth analysis of the data uncovered that primary emissions from coal combustion and biomass burning together with secondary formation of sulfate (mainly from SO2 emitted by coal combustion) are important driving factors for haze evolution. Our findings provide useful insights into air pollution control in heavily polluted regions.
Shan Zhou, Sonya Collier, Daniel A. Jaffe, Nicole L. Briggs, Jonathan Hee, Arthur J. Sedlacek III, Lawrence Kleinman, Timothy B. Onasch, and Qi Zhang
Atmos. Chem. Phys., 17, 2477–2493, https://doi.org/10.5194/acp-17-2477-2017, https://doi.org/10.5194/acp-17-2477-2017, 2017
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Wildfire plumes in the western US were sampled at a high-elevation site in summer 2013. Three distinct BBOA types were identified, representing biomass burning OA with different degrees of atmospheric processing. Analysis of consecutive BB plumes transported from the same fire source showed that photooxidation led to enhanced mass fractions of aged BBOAs but negligible net OA production. A possible reason is that SOA formation was almost entirely balanced by BBOA volatilization during transport.
Hwajin Kim, Qi Zhang, Gwi-Nam Bae, Jin Young Kim, and Seung Bok Lee
Atmos. Chem. Phys., 17, 2009–2033, https://doi.org/10.5194/acp-17-2009-2017, https://doi.org/10.5194/acp-17-2009-2017, 2017
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We discuss characteristics, sources, and size distributions of the PM1 composition and OA components in Seoul, Korea, in winter. The serious pollution observed was caused by a combination of various factors, including meteorological conditions, emissions from local primary sources, secondary formation, and transport of air masses from upwind locations. This will be very useful for enacting effective PM reduction strategies for Korea as well as for the broader northern pan-Eurasian region.
Adam P. Bateman, Zhaoheng Gong, Tristan H. Harder, Suzane S. de Sá, Bingbing Wang, Paulo Castillo, Swarup China, Yingjun Liu, Rachel E. O'Brien, Brett B. Palm, Hung-Wei Shiu, Glauber G. Cirino, Ryan Thalman, Kouji Adachi, M. Lizabeth Alexander, Paulo Artaxo, Allan K. Bertram, Peter R. Buseck, Mary K. Gilles, Jose L. Jimenez, Alexander Laskin, Antonio O. Manzi, Arthur Sedlacek, Rodrigo A. F. Souza, Jian Wang, Rahul Zaveri, and Scot T. Martin
Atmos. Chem. Phys., 17, 1759–1773, https://doi.org/10.5194/acp-17-1759-2017, https://doi.org/10.5194/acp-17-1759-2017, 2017
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The occurrence of nonliquid and liquid physical states of submicron atmospheric particulate matter (PM) downwind of an urban region in central Amazonia was investigated. Air masses representing background conditions, urban pollution, and regional- and continental-scale biomass were measured. Anthropogenic influences contributed to the presence of nonliquid PM in the atmospheric particle population, while liquid PM dominated during periods of biogenic influence.
Emma L. D'Ambro, Ben H. Lee, Jiumeng Liu, John E. Shilling, Cassandra J. Gaston, Felipe D. Lopez-Hilfiker, Siegfried Schobesberger, Rahul A. Zaveri, Claudia Mohr, Anna Lutz, Zhenfa Zhang, Avram Gold, Jason D. Surratt, Jean C. Rivera-Rios, Frank N. Keutsch, and Joel A. Thornton
Atmos. Chem. Phys., 17, 159–174, https://doi.org/10.5194/acp-17-159-2017, https://doi.org/10.5194/acp-17-159-2017, 2017
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We studied the formation and properties of secondary organic aerosol produced from isoprene. We find that a significant fraction (~50 %) of the mass is composed of low-volatility, highly oxidized compounds such as C5H12O6. A significant fraction of the remainder appears to be in the form of oligomeric material. Adding NOx maintained or decreased SOA yields while increasing the fraction of low-volatility material, possibly due to oligomers.
Jianzhong Xu, Jinsen Shi, Qi Zhang, Xinlei Ge, Francesco Canonaco, André S. H. Prévôt, Matthias Vonwiller, Sönke Szidat, Jinming Ge, Jianmin Ma, Yanqing An, Shichang Kang, and Dahe Qin
Atmos. Chem. Phys., 16, 14937–14957, https://doi.org/10.5194/acp-16-14937-2016, https://doi.org/10.5194/acp-16-14937-2016, 2016
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This study deployed an AMS field study in Lanzhou, a city in northwestern China, evaluating the chemical composition, sources, and processes of urban aerosols during wintertime. In comparison with the results during summer in Lanzhou, the air pollution during winter was more severe and the sources were more complex. In addition, this paper estimates the contributions of fossil and non-fossil sources of organic carbon to primary and secondary organic carbon using the carbon isotopic method.
M. Dale Stokes, Grant Deane, Douglas B. Collins, Christopher Cappa, Timothy Bertram, Abigail Dommer, Steven Schill, Sara Forestieri, and Mathew Survilo
Atmos. Meas. Tech., 9, 4257–4267, https://doi.org/10.5194/amt-9-4257-2016, https://doi.org/10.5194/amt-9-4257-2016, 2016
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A small breaking wave and foam simulator has been fabricated that allows the continuous analysis of the produced marine aerosols. Based on the original Marine Aerosol Reference Tank (MART) the miniature version allows the culturing of delicate planktonic organisms because it operates without a large, sheer-inducing pump. This allows the study of marine aerosol production and the effects of biologically controlled seawater chemistry under controlled and repeatable experimental conditions.
Naruki Hiranuma, Ottmar Möhler, Gourihar Kulkarni, Martin Schnaiter, Steffen Vogt, Paul Vochezer, Emma Järvinen, Robert Wagner, David M. Bell, Jacqueline Wilson, Alla Zelenyuk, and Daniel J. Cziczo
Atmos. Meas. Tech., 9, 3817–3836, https://doi.org/10.5194/amt-9-3817-2016, https://doi.org/10.5194/amt-9-3817-2016, 2016
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A new pumped counterflow virtual impactor (PCVI) called the ice-selecting PCVI (IS-PCVI) has been developed to collect ice crystal residuals for investigating physico-chemical properties of ice-nucleating particles. The results show that the ice crystals of volume-equivalent diameter ~ 10 to 30 µm can be efficiently separated from the supercooled droplets and interstitial particles. The IS-PCVI is efficient when the counterflow-to-input flow ratio is within 0.09 to 0.18.
Junfeng Wang, Xinlei Ge, Yanfang Chen, Yafei Shen, Qi Zhang, Yele Sun, Jianzhong Xu, Shun Ge, Huan Yu, and Mindong Chen
Atmos. Chem. Phys., 16, 9109–9127, https://doi.org/10.5194/acp-16-9109-2016, https://doi.org/10.5194/acp-16-9109-2016, 2016
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Highly time- and chemically resolved submicron aerosol properties were characterized online for the first time during springtime in Nanjing by using the Aerodyne SP-AMS. Both chemical and size information of black carbon together with other aerosol species were simultaneously determined. An in-depth analysis of the data elucidates the sources and evolution processes of the fine aerosols in the YRD region. Our findings are valuable for air quality remediation in the densely populated regions.
Sara D. Forestieri, Gavin C. Cornwell, Taylor M. Helgestad, Kathryn A. Moore, Christopher Lee, Gordon A. Novak, Camille M. Sultana, Xiaofei Wang, Timothy H. Bertram, Kimberly A. Prather, and Christopher D. Cappa
Atmos. Chem. Phys., 16, 9003–9018, https://doi.org/10.5194/acp-16-9003-2016, https://doi.org/10.5194/acp-16-9003-2016, 2016
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Hygroscopic growth factors at 85 % relative humidity (GF(85 %)) were quantified along with particle composition for primary sea spray aerosol (SSA) particles generated in marine aerosol reference tanks (MARTs) from seawater in which two independent phytoplankton blooms were induced. The observed 5 to 15 % depression in the GF(85 %) values (relative to pure sea salt) is consistent with the large observed volume fractions of non-refractory organic matter (NR-OM) comprising the SSA.
Mijung Song, Pengfei F. Liu, Sarah J. Hanna, Rahul A. Zaveri, Katie Potter, Yuan You, Scot T. Martin, and Allan K. Bertram
Atmos. Chem. Phys., 16, 8817–8830, https://doi.org/10.5194/acp-16-8817-2016, https://doi.org/10.5194/acp-16-8817-2016, 2016
Yele Sun, Wei Du, Pingqing Fu, Qingqing Wang, Jie Li, Xinlei Ge, Qi Zhang, Chunmao Zhu, Lujie Ren, Weiqi Xu, Jian Zhao, Tingting Han, Douglas R. Worsnop, and Zifa Wang
Atmos. Chem. Phys., 16, 8309–8329, https://doi.org/10.5194/acp-16-8309-2016, https://doi.org/10.5194/acp-16-8309-2016, 2016
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We have a comprehensive characterization of the sources, variations and processes of submicron aerosols in Beijing in winter using HR-AMS and GC/MS measurements. The primary sources including traffic, cooking, biomass burning and coal combustion emissions, and secondary components were separated and quantified with PMF. Our results elucidated the important roles of primary emissions, particularly coal combustion, and aqueous-phase processing in the formation of severe air pollution in winter.
Alma Hodzic, Prasad S. Kasibhatla, Duseong S. Jo, Christopher D. Cappa, Jose L. Jimenez, Sasha Madronich, and Rokjin J. Park
Atmos. Chem. Phys., 16, 7917–7941, https://doi.org/10.5194/acp-16-7917-2016, https://doi.org/10.5194/acp-16-7917-2016, 2016
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The global budget and spatial distribution of secondary organic aerosol (SOA) are highly uncertain in chemistry-climate models, which reflects our inability to characterize all phases of the OA lifecycle. We have performed global model simulations with the newly proposed formation and removal processes (photolysis and heterogeneous chemistry) and shown that SOA is a far more dynamic system, with 4 times stronger production rates and more efficient removal mechanisms, than assumed in models.
Dominique E. Young, Hwajin Kim, Caroline Parworth, Shan Zhou, Xiaolu Zhang, Christopher D. Cappa, Roger Seco, Saewung Kim, and Qi Zhang
Atmos. Chem. Phys., 16, 5427–5451, https://doi.org/10.5194/acp-16-5427-2016, https://doi.org/10.5194/acp-16-5427-2016, 2016
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Aerosol chemistry and the sources and processes driving the observed temporal and diurnal variations of PM were studied in a polluted urban environment during winter 2013. These results were compared to a similar campaign from winter 2010. Meteorology strongly influenced PM composition, both directly and indirectly. Nighttime reactions played a more important role in 2013 and the influence from a nighttime formed residual layer that mixed down in the morning was also much more intense in 2013.
Lu Yu, Jeremy Smith, Alexander Laskin, Katheryn M. George, Cort Anastasio, Julia Laskin, Ann M. Dillner, and Qi Zhang
Atmos. Chem. Phys., 16, 4511–4527, https://doi.org/10.5194/acp-16-4511-2016, https://doi.org/10.5194/acp-16-4511-2016, 2016
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The chemical evolution of SOA formed during aqueous reactions of phenolic compounds is studied via combined bulk and molecular analysis. Phenolic SOA evolve dynamically during photochemical aging, with different reaction mechanisms (oligomerization, fragmentation, and functionalization) leading to different generations of products that span an enormous range in volatilities and a large range in oxidation state and composition. Aqueous reactions of phenols are likely an important source of ELVOC.
Duseong S. Jo, Rokjin J. Park, Seungun Lee, Sang-Woo Kim, and Xiaolu Zhang
Atmos. Chem. Phys., 16, 3413–3432, https://doi.org/10.5194/acp-16-3413-2016, https://doi.org/10.5194/acp-16-3413-2016, 2016
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We develop a new approach to estimate global emission of primary brown carbon from biomass burning and biofuel use and explicitly simulate brown carbon aerosol that has not been considered in climate and air quality models despite of its importance for solar absorption at UV and short visible wavelengths. Using our best simulation results, we estimate radiative effects of brown carbon aerosol for climate and photochemistry.
Christopher D. Cappa, Shantanu H. Jathar, Michael J. Kleeman, Kenneth S. Docherty, Jose L. Jimenez, John H. Seinfeld, and Anthony S. Wexler
Atmos. Chem. Phys., 16, 3041–3059, https://doi.org/10.5194/acp-16-3041-2016, https://doi.org/10.5194/acp-16-3041-2016, 2016
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Losses of vapors to walls of chambers can negatively bias SOA formation measurements, consequently leading to low predicted SOA concentrations in air quality models. Here, we show that accounting for such vapor losses leads to substantial increases in the predicted amount of SOA formed from VOCs and to notable increases in the O : C atomic ratio in two US regions. Comparison with a variety of observational data suggests generally improved model performance when vapor wall losses are accounted for.
S. E. Pusede, K. C. Duffey, A. A. Shusterman, A. Saleh, J. L. Laughner, P. J. Wooldridge, Q. Zhang, C. L. Parworth, H. Kim, S. L. Capps, L. C. Valin, C. D. Cappa, A. Fried, J. Walega, J. B. Nowak, A. J. Weinheimer, R. M. Hoff, T. A. Berkoff, A. J. Beyersdorf, J. Olson, J. H. Crawford, and R. C. Cohen
Atmos. Chem. Phys., 16, 2575–2596, https://doi.org/10.5194/acp-16-2575-2016, https://doi.org/10.5194/acp-16-2575-2016, 2016
S. H. Jathar, C. D. Cappa, A. S. Wexler, J. H. Seinfeld, and M. J. Kleeman
Atmos. Chem. Phys., 16, 2309–2322, https://doi.org/10.5194/acp-16-2309-2016, https://doi.org/10.5194/acp-16-2309-2016, 2016
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Multi-generational chemistry schemes applied in regional models do not increase secondary organic aerosol (SOA) mass production relative to traditional "two-product" schemes when both models are fitted to the same chamber data. The multi-generational chemistry schemes do change the predicted composition of SOA and the source attribution of SOA.
L. Kleinman, C. Kuang, A. Sedlacek, G. Senum, S. Springston, J. Wang, Q. Zhang, J. Jayne, J. Fast, J. Hubbe, J. Shilling, and R. Zaveri
Atmos. Chem. Phys., 16, 1729–1746, https://doi.org/10.5194/acp-16-1729-2016, https://doi.org/10.5194/acp-16-1729-2016, 2016
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Atmospheric measurements of total organic aerosol (OA) and tracers of anthropogenic and biogenic emissions are used to quantify synergistic effects (A–B interactions) between two classes of precursors in the formation of OA. Regressions are consistent with the Sacramento plume composed mainly of modern carbon, and OA correlating best with an anthropogenic tracer. It is found that meteorological conditions during a pollution episode can mimic effects of A–B interactions.
L. M. Zamora, R. A. Kahn, M. J. Cubison, G. S. Diskin, J. L. Jimenez, Y. Kondo, G. M. McFarquhar, A. Nenes, K. L. Thornhill, A. Wisthaler, A. Zelenyuk, and L. D. Ziemba
Atmos. Chem. Phys., 16, 715–738, https://doi.org/10.5194/acp-16-715-2016, https://doi.org/10.5194/acp-16-715-2016, 2016
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Based on extensive aircraft campaigns, we quantify how biomass burning smoke affects subarctic and Arctic liquid cloud microphysical properties. Enhanced cloud albedo may decrease short-wave radiative flux by between 2 and 4 Wm2 or more in some subarctic conditions. Smoke halved average cloud droplet diameter. In one case study, it also appeared to limit droplet formation. Numerous Arctic background Aitken particles can also interact with combustion particles, perhaps affecting their properties.
C. Chen, Y. L. Sun, W. Q. Xu, W. Du, L. B. Zhou, T. T. Han, Q. Q. Wang, P. Q. Fu, Z. F. Wang, Z. Q. Gao, Q. Zhang, and D. R. Worsnop
Atmos. Chem. Phys., 15, 12879–12895, https://doi.org/10.5194/acp-15-12879-2015, https://doi.org/10.5194/acp-15-12879-2015, 2015
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A comprehensive characterization of submicron aerosol composition and sources at 260m in urban Beijing during APEC 2014 is presented. Aerosol species were shown to decrease substantially by 40–80% during APEC, whereas the bulk composition was relatively similar to the result of synergetic controls of secondary precursors. Our results elucidated that the good air quality during APEC was the combined result of emission controls and meteorological effects, with the former playing the dominant role.
A. Lupascu, R. Easter, R. Zaveri, M. Shrivastava, M. Pekour, J. Tomlinson, Q. Yang, H. Matsui, A. Hodzic, Q. Zhang, and J. D. Fast
Atmos. Chem. Phys., 15, 12283–12313, https://doi.org/10.5194/acp-15-12283-2015, https://doi.org/10.5194/acp-15-12283-2015, 2015
Y. L. Sun, Z. F. Wang, W. Du, Q. Zhang, Q. Q. Wang, P. Q. Fu, X. L. Pan, J. Li, J. Jayne, and D. R. Worsnop
Atmos. Chem. Phys., 15, 10149–10165, https://doi.org/10.5194/acp-15-10149-2015, https://doi.org/10.5194/acp-15-10149-2015, 2015
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We conducted the first long-term real-time measurement of submicron aerosol composition in Beijing using an ACSM for 1 year. The seasonal variations of mass concentrations and chemical composition of submicron aerosol were investigated in detail, and the meteorological effects on aerosol chemistry, particularly temperature and relative humidity, were elucidated. Finally, the potential source areas of aerosol species during four seasons were identified.
K. R. Kolesar, C. Chen, D. Johnson, and C. D. Cappa
Atmos. Chem. Phys., 15, 9327–9343, https://doi.org/10.5194/acp-15-9327-2015, https://doi.org/10.5194/acp-15-9327-2015, 2015
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Secondary organic aerosol from the dark ozonolysis of α‑pinene was formed at a range of mass loadings from 1 to 800μg m-3. The amount of mass loss during evaporation in a thermodenuder was found to be independent of mass loading. A kinetic model of evaporation was fit to the observations and good agreement was obtained when the particle was either composed of dimers that decompose into semi-volatile monomers or when it was composed of low-volatility compounds that evaporate directly.
S. H. Jathar, C. D. Cappa, A. S. Wexler, J. H. Seinfeld, and M. J. Kleeman
Geosci. Model Dev., 8, 2553–2567, https://doi.org/10.5194/gmd-8-2553-2015, https://doi.org/10.5194/gmd-8-2553-2015, 2015
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Multi-generational oxidation of organic vapors can significantly alter the mass, chemical composition and properties of secondary organic aerosol (SOA). Here, we implement a semi-explicit, constrained multi-generational oxidation model of Cappa and Wilson (2012) in a 3-D air quality model. When compared with results from a current-generation SOA model, we predict similar mass concentrations of SOA but a different chemical composition. O:C ratios of SOA are in line with those measured globally.
J. Z. Xu, Q. Zhang, Z. B. Wang, G. M. Yu, X. L. Ge, and X. Qin
Atmos. Chem. Phys., 15, 5069–5081, https://doi.org/10.5194/acp-15-5069-2015, https://doi.org/10.5194/acp-15-5069-2015, 2015
D. B. Atkinson, J. G. Radney, J. Lum, K. R. Kolesar, D. J. Cziczo, M. S. Pekour, Q. Zhang, A. Setyan, A. Zelenyuk, and C. D. Cappa
Atmos. Chem. Phys., 15, 4045–4061, https://doi.org/10.5194/acp-15-4045-2015, https://doi.org/10.5194/acp-15-4045-2015, 2015
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This work describes an analysis of measurements of the influence of water uptake on the light-scattering properties of sub- and supermicron-sized particles as observed in the Sacramento, CA, USA region during the 2010 CARES field campaign. The observations are used to derive campaign-average effective hygroscopicity parameters for submicron oxygenated organic aerosol and for supermicron particles, and the influence of chloride displacement reactions on particle hygroscopicity is examined.
D. Lowe, S. Archer-Nicholls, W. Morgan, J. Allan, S. Utembe, B. Ouyang, E. Aruffo, M. Le Breton, R. A. Zaveri, P. Di Carlo, C. Percival, H. Coe, R. Jones, and G. McFiggans
Atmos. Chem. Phys., 15, 1385–1409, https://doi.org/10.5194/acp-15-1385-2015, https://doi.org/10.5194/acp-15-1385-2015, 2015
L. Yu, J. Smith, A. Laskin, C. Anastasio, J. Laskin, and Q. Zhang
Atmos. Chem. Phys., 14, 13801–13816, https://doi.org/10.5194/acp-14-13801-2014, https://doi.org/10.5194/acp-14-13801-2014, 2014
J. Xu, Q. Zhang, M. Chen, X. Ge, J. Ren, and D. Qin
Atmos. Chem. Phys., 14, 12593–12611, https://doi.org/10.5194/acp-14-12593-2014, https://doi.org/10.5194/acp-14-12593-2014, 2014
S. Archer-Nicholls, D. Lowe, S. Utembe, J. Allan, R. A. Zaveri, J. D. Fast, Ø. Hodnebrog, H. Denier van der Gon, and G. McFiggans
Geosci. Model Dev., 7, 2557–2579, https://doi.org/10.5194/gmd-7-2557-2014, https://doi.org/10.5194/gmd-7-2557-2014, 2014
K. Tsigaridis, N. Daskalakis, M. Kanakidou, P. J. Adams, P. Artaxo, R. Bahadur, Y. Balkanski, S. E. Bauer, N. Bellouin, A. Benedetti, T. Bergman, T. K. Berntsen, J. P. Beukes, H. Bian, K. S. Carslaw, M. Chin, G. Curci, T. Diehl, R. C. Easter, S. J. Ghan, S. L. Gong, A. Hodzic, C. R. Hoyle, T. Iversen, S. Jathar, J. L. Jimenez, J. W. Kaiser, A. Kirkevåg, D. Koch, H. Kokkola, Y. H Lee, G. Lin, X. Liu, G. Luo, X. Ma, G. W. Mann, N. Mihalopoulos, J.-J. Morcrette, J.-F. Müller, G. Myhre, S. Myriokefalitakis, N. L. Ng, D. O'Donnell, J. E. Penner, L. Pozzoli, K. J. Pringle, L. M. Russell, M. Schulz, J. Sciare, Ø. Seland, D. T. Shindell, S. Sillman, R. B. Skeie, D. Spracklen, T. Stavrakou, S. D. Steenrod, T. Takemura, P. Tiitta, S. Tilmes, H. Tost, T. van Noije, P. G. van Zyl, K. von Salzen, F. Yu, Z. Wang, Z. Wang, R. A. Zaveri, H. Zhang, K. Zhang, Q. Zhang, and X. Zhang
Atmos. Chem. Phys., 14, 10845–10895, https://doi.org/10.5194/acp-14-10845-2014, https://doi.org/10.5194/acp-14-10845-2014, 2014
E. Kassianov, J. Barnard, M. Pekour, L. K. Berg, J. Shilling, C. Flynn, F. Mei, and A. Jefferson
Atmos. Meas. Tech., 7, 3247–3261, https://doi.org/10.5194/amt-7-3247-2014, https://doi.org/10.5194/amt-7-3247-2014, 2014
J. D. Fast, J. Allan, R. Bahreini, J. Craven, L. Emmons, R. Ferrare, P. L. Hayes, A. Hodzic, J. Holloway, C. Hostetler, J. L. Jimenez, H. Jonsson, S. Liu, Y. Liu, A. Metcalf, A. Middlebrook, J. Nowak, M. Pekour, A. Perring, L. Russell, A. Sedlacek, J. Seinfeld, A. Setyan, J. Shilling, M. Shrivastava, S. Springston, C. Song, R. Subramanian, J. W. Taylor, V. Vinoj, Q. Yang, R. A. Zaveri, and Q. Zhang
Atmos. Chem. Phys., 14, 10013–10060, https://doi.org/10.5194/acp-14-10013-2014, https://doi.org/10.5194/acp-14-10013-2014, 2014
P. Roldin, A. C. Eriksson, E. Z. Nordin, E. Hermansson, D. Mogensen, A. Rusanen, M. Boy, E. Swietlicki, B. Svenningsson, A. Zelenyuk, and J. Pagels
Atmos. Chem. Phys., 14, 7953–7993, https://doi.org/10.5194/acp-14-7953-2014, https://doi.org/10.5194/acp-14-7953-2014, 2014
A. Setyan, C. Song, M. Merkel, W. B. Knighton, T. B. Onasch, M. R. Canagaratna, D. R. Worsnop, A. Wiedensohler, J. E. Shilling, and Q. Zhang
Atmos. Chem. Phys., 14, 6477–6494, https://doi.org/10.5194/acp-14-6477-2014, https://doi.org/10.5194/acp-14-6477-2014, 2014
C. Knote, A. Hodzic, J. L. Jimenez, R. Volkamer, J. J. Orlando, S. Baidar, J. Brioude, J. Fast, D. R. Gentner, A. H. Goldstein, P. L. Hayes, W. B. Knighton, H. Oetjen, A. Setyan, H. Stark, R. Thalman, G. Tyndall, R. Washenfelder, E. Waxman, and Q. Zhang
Atmos. Chem. Phys., 14, 6213–6239, https://doi.org/10.5194/acp-14-6213-2014, https://doi.org/10.5194/acp-14-6213-2014, 2014
J. C. Kaiser, J. Hendricks, M. Righi, N. Riemer, R. A. Zaveri, S. Metzger, and V. Aquila
Geosci. Model Dev., 7, 1137–1157, https://doi.org/10.5194/gmd-7-1137-2014, https://doi.org/10.5194/gmd-7-1137-2014, 2014
R. A. Zaveri, R. C. Easter, J. E. Shilling, and J. H. Seinfeld
Atmos. Chem. Phys., 14, 5153–5181, https://doi.org/10.5194/acp-14-5153-2014, https://doi.org/10.5194/acp-14-5153-2014, 2014
G. M. Buffaloe, D. A. Lack, E. J. Williams, D. Coffman, K. L. Hayden, B. M. Lerner, S.-M. Li, I. Nuaaman, P. Massoli, T. B. Onasch, P. K. Quinn, and C. D. Cappa
Atmos. Chem. Phys., 14, 1881–1896, https://doi.org/10.5194/acp-14-1881-2014, https://doi.org/10.5194/acp-14-1881-2014, 2014
C. D. Cappa, E. J. Williams, D. A. Lack, G. M. Buffaloe, D. Coffman, K. L. Hayden, S. C. Herndon, B. M. Lerner, S.-M. Li, P. Massoli, R. McLaren, I. Nuaaman, T. B. Onasch, and P. K. Quinn
Atmos. Chem. Phys., 14, 1337–1352, https://doi.org/10.5194/acp-14-1337-2014, https://doi.org/10.5194/acp-14-1337-2014, 2014
F. Mei, A. Setyan, Q. Zhang, and J. Wang
Atmos. Chem. Phys., 13, 12155–12169, https://doi.org/10.5194/acp-13-12155-2013, https://doi.org/10.5194/acp-13-12155-2013, 2013
B. Friedman, A. Zelenyuk, J. Beranek, G. Kulkarni, M. Pekour, A. Gannet Hallar, I. B. McCubbin, J. A. Thornton, and D. J Cziczo
Atmos. Chem. Phys., 13, 11839–11851, https://doi.org/10.5194/acp-13-11839-2013, https://doi.org/10.5194/acp-13-11839-2013, 2013
C. Zhao, S. Chen, L. R. Leung, Y. Qian, J. F. Kok, R. A. Zaveri, and J. Huang
Atmos. Chem. Phys., 13, 10733–10753, https://doi.org/10.5194/acp-13-10733-2013, https://doi.org/10.5194/acp-13-10733-2013, 2013
R. C. Moffet, T. C. Rödel, S. T. Kelly, X. Y. Yu, G. T. Carroll, J. Fast, R. A. Zaveri, A. Laskin, and M. K. Gilles
Atmos. Chem. Phys., 13, 10445–10459, https://doi.org/10.5194/acp-13-10445-2013, https://doi.org/10.5194/acp-13-10445-2013, 2013
M. Gyawali, W. P. Arnott, R. A. Zaveri, C. Song, M. Pekour, B. Flowers, M. K. Dubey, A. Setyan, Q. Zhang, J. W. Harworth, J. G. Radney, D. B. Atkinson, S. China, C. Mazzoleni, K. Gorkowski, R. Subramanian, B. T. Jobson, and H. Moosmüller
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-7113-2013, https://doi.org/10.5194/acpd-13-7113-2013, 2013
Revised manuscript not accepted
J. E. Shilling, R. A. Zaveri, J. D. Fast, L. Kleinman, M. L. Alexander, M. R. Canagaratna, E. Fortner, J. M. Hubbe, J. T. Jayne, A. Sedlacek, A. Setyan, S. Springston, D. R. Worsnop, and Q. Zhang
Atmos. Chem. Phys., 13, 2091–2113, https://doi.org/10.5194/acp-13-2091-2013, https://doi.org/10.5194/acp-13-2091-2013, 2013
C. D. Cappa, X. Zhang, C. L. Loza, J. S. Craven, L. D. Yee, and J. H. Seinfeld
Atmos. Chem. Phys., 13, 1591–1606, https://doi.org/10.5194/acp-13-1591-2013, https://doi.org/10.5194/acp-13-1591-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Pollution affects Arabian and Saharan dust optical properties in the eastern Mediterranean
Phase matrix characterization of long-range-transported Saharan dust using multiwavelength-polarized polar imaging nephelometry
Measurement report: The influence of particle number size distribution and hygroscopicity on the microphysical properties of cloud droplets at a mountain site
Measurement report: Long-term assessment of primary and secondary organic aerosols in the Shanghai megacity throughout China's Clean Air actions since 2010
The evolution of aerosol mixing state derived from a field campaign in Beijing: implications for particle aging timescales in urban atmospheres
Measurement report: Size-resolved particle effective density measured by an AAC-SMPS and implications for chemical composition
Measurement report: Aircraft observations of aerosol and microphysical quantities of stratocumulus in autumn over Guangxi Province, China – daylight variation, vertical distribution, and aerosol–cloud interactions
Hygroscopic aerosols amplify longwave downward radiation in the Arctic
Measurement report: Aerosol and cloud nuclei properties along the Central and Northern Great Barrier Reef: Impact of continental emissions
Measurement report: Optical and structural properties of atmospheric water-soluble organic carbon in China – insights from multi-site spectroscopic measurements
Measurement report: The variation properties of aerosol hygroscopic growth related to chemical composition during new particle formation days in a coastal city of Southeast China
In situ vertical observations of the layered structure of air pollution in a continental high-latitude urban boundary layer during winter
Size-resolved hygroscopicity and volatility properties of ambient urban aerosol particles measured by a volatility hygroscopicity tandem differential mobility analyzer system in Beijing
Terrestrial runoff is an important source of biological ice-nucleating particles in Arctic marine systems
Characterization of aerosol over the eastern Mediterranean by polarization-sensitive Raman lidar measurements during A-LIFE – aerosol type classification and type separation
Aerosol spectral optical properties in the Paris urban area and its peri-urban and forested surroundings during summer 2022 from ACROSS surface observations
Measurement report: An investigation of the spatiotemporal variability in aerosols in the mountainous terrain of the upper Colorado River basin using SAIL-Net
Contributions of the synoptic meteorology to the seasonal cloud condensation nuclei cycle over the Southern Ocean
Measurement report: Cloud condensation nuclei (CCN) activity in the South China Sea from shipborne observations during the summer and winter of 2021 – seasonal variation and anthropogenic influence
Differential characterization of air ions in boreal forest of Finland and megacity of eastern China
Source-Dependent Optical Properties and Molecular Characteristics of Atmospheric Brown Carbon
On-road vehicle emission measurements show a significant reduction of black carbon and nitrogen oxides emissions in Euro6c and 6d diesel-powered cars
Measurement report: A comparative analysis of an intensive incursion of fluorescing African dust particles over Puerto Rico and another over Spain
Measurement report: Analysis of aerosol optical depth variation at Zhongshan Station in Antarctica
External particle mixing influences hygroscopicity in a sub-urban area
Long-term observations of black carbon and carbon monoxide in the Poker Flat Research Range, central Alaska, with a focus on forest wildfire emissions
Origin, size distribution and hygroscopic properties of marine aerosols in the south-western Indian Ocean: report of 6 campaigns of shipborne observations
High ice-nucleating particle concentrations associated with Arctic haze in springtime cold-air outbreaks
CCN estimations at a high-altitude remote site: role of organic aerosol variability and hygroscopicity
Aerosol hygroscopicity over the southeast Atlantic Ocean during the biomass burning season – Part 1: From the perspective of scattering enhancement
Spatial, temporal, and meteorological impact of the 26 February 2023 dust storm: increase in particulate matter concentrations across New Mexico and West Texas
Large spatiotemporal variability in aerosol properties over central Argentina during the CACTI field campaign
Microphysical properties of refractory black carbon aerosols for different air masses at a central European background site
Quantification and characterization of primary biological aerosol particles and microbes aerosolized from Baltic seawater
Brownness of organics in anthropogenic biomass burning aerosols over South Asia
Multi-year black carbon observations and modeling close to the largest gas flaring and wildfire regions (Western Siberian Arctic)
Strong influence of Black Carbon on aerosol optical properties in Central Amazonia during the fire season
Source apportionment of particle number size distribution at the street canyon and urban background sites
Long-range transport of coarse mineral dust: an evaluation of the Met Office Unified Model against aircraft observations
Extreme Saharan dust events expand northward over the Atlantic and Europe, prompting record-breaking PM10 and PM2.5 episodes
Atmospheric black carbon in the metropolitan area of La Paz and El Alto, Bolivia: concentration levels and emission sources
Changing optical properties of black carbon and brown carbon aerosols during long-range transport from the Indo-Gangetic Plain to the equatorial Indian Ocean
Aerosol size distribution properties associated with cold-air outbreaks in the Norwegian Arctic
Ice-nucleating particles active below −24 °C in a Finnish boreal forest and their relationship to bioaerosols
Measurements of particle emissions of an A350-941 burning 100 % sustainable aviation fuels in cruise
Vertical distribution of ice nucleating particles over the boreal forest of Hyytiälä, Finland
Multi-year gradient measurements of sea spray fluxes over the Baltic Sea and the North Atlantic Ocean
Measurement report: In situ vertical profiles of below-cloud aerosol over the central Greenland Ice Sheet
Occurrence, abundance, and formation of atmospheric tarballs from a wide range of wildfires in the western US
Measurement report: Contribution of atmospheric new particle formation to ultrafine particle concentration, cloud condensation nuclei, and radiative forcing – results from 5-year observations in central Europe
Marilena Teri, Josef Gasteiger, Katharina Heimerl, Maximilian Dollner, Manuel Schöberl, Petra Seibert, Anne Tipka, Thomas Müller, Sudharaj Aryasree, Konrad Kandler, and Bernadett Weinzierl
Atmos. Chem. Phys., 25, 6633–6662, https://doi.org/10.5194/acp-25-6633-2025, https://doi.org/10.5194/acp-25-6633-2025, 2025
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The A-LIFE aircraft field experiment was carried out in the eastern Mediterranean in 2017. Using A-LIFE data, we studied the change in mineral dust optical properties due to mixing with anthropogenic aerosols. We found that increasing pollution affects dust optical properties, which has implications for identifying dust events and understanding their climate effects. We also show that optical properties of Saharan and Arabian dust are similar when comparing cases with equal pollution content.
Elena Bazo, Daniel Pérez-Ramírez, Antonio Valenzuela, J. Vanderlei Martins, Gloria Titos, Alberto Cazorla, Fernando Rejano, Diego Patrón, Arlett Díaz-Zurita, Francisco José García-Izquierdo, David Fuertes, Lucas Alados-Arboledas, and Francisco José Olmo
Atmos. Chem. Phys., 25, 6325–6352, https://doi.org/10.5194/acp-25-6325-2025, https://doi.org/10.5194/acp-25-6325-2025, 2025
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This works analyzes the aerosol scattering phase function for transported Saharan dust to the city of Granada – located in southwestern Europe. We use the novel technique polar imaging nephelometry that helps to determine the phase functions using a CMOS camera. The capability of measuring with polarized light helps to infer new properties about the mixture of Saharan dust particles with those of anthropogenic origin.
Xiaojing Shen, Quan Liu, Junying Sun, Wanlin Kong, Qianli Ma, Bing Qi, Lujie Han, Yangmei Zhang, Linlin Liang, Lei Liu, Shuo Liu, Xinyao Hu, Jiayuan Lu, Aoyuan Yu, Huizheng Che, and Xiaoye Zhang
Atmos. Chem. Phys., 25, 5711–5725, https://doi.org/10.5194/acp-25-5711-2025, https://doi.org/10.5194/acp-25-5711-2025, 2025
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In this work, an automatic switched inlet system was developed and employed to investigate the aerosols and cloud droplets at a mountain site with frequent cloud processes. It showed different characteristics of cloud residual and interstitial particles. Stronger particle hygroscopicity reduced liquid water content and smaller cloud droplet diameters. This investigation contributes to understanding aerosol–cloud interactions by assessing the impact of aerosol particles on cloud microphysics.
Haifeng Yu, Yunhua Chang, Lin Cheng, Yusen Duan, and Jianlin Hu
Atmos. Chem. Phys., 25, 5355–5369, https://doi.org/10.5194/acp-25-5355-2025, https://doi.org/10.5194/acp-25-5355-2025, 2025
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This study presents long-term measurements and comprehensive analysis of carbonaceous aerosols in fine particles in Shanghai. We further estimated primary and secondary carbon levels, examining their temporal variations on interannual, monthly, seasonal, and diurnal scales. Through rigorous statistical analysis and correlation studies with meteorological parameters and pollutant concentrations, the origins, formation mechanisms, and spatial distribution patterns of secondary organic carbon were elucidated.
Jieyao Liu, Fang Zhang, Jingye Ren, Lu Chen, Anran Zhang, Zhe Wang, Songjian Zou, Honghao Xu, and Xingyan Yue
Atmos. Chem. Phys., 25, 5075–5086, https://doi.org/10.5194/acp-25-5075-2025, https://doi.org/10.5194/acp-25-5075-2025, 2025
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Particle mixing states and aging timescales are important for the evaluation of aerosol climate effects, but they are poorly parameterized in current models. We unravel the evolution of real-time mixing states and the aging timescale of size-resolved particles based on field measurements in urban Beijing. This study provides an observational basis for accurately parameterizing the aging timescale of aerosol particles in climate models.
Yao Song, Jing Wei, Wenlong Zhao, Jinmei Ding, Xiangyu Pei, Fei Zhang, Zhengning Xu, Ruifang Shi, Ya Wei, Lu Zhang, Lingling Jin, and Zhibin Wang
Atmos. Chem. Phys., 25, 4755–4766, https://doi.org/10.5194/acp-25-4755-2025, https://doi.org/10.5194/acp-25-4755-2025, 2025
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This study investigates the size-resolved effective density (ρeff) of aerosol particles in Hangzhou using a tandem aerodynamic aerosol classifier and scanning mobility particle sizer system. The ρeff values ranged from 1.47 to 1.63 g cm-3, increasing with particle diameter. The relationship between ρeff and the particle diameter varies due to differences in the chemical composition of the particles. A new method to derive the size-resolved chemical composition of particles from ρeff is proposed.
Sihan Liu, Honglei Wang, Delong Zhao, Wei Zhou, Yuanmou Du, Zhengguo Zhang, Peng Cheng, Tianliang Zhao, Yue Ke, Zihao Wu, and Mengyu Huang
Atmos. Chem. Phys., 25, 4151–4165, https://doi.org/10.5194/acp-25-4151-2025, https://doi.org/10.5194/acp-25-4151-2025, 2025
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To understand the effect of aerosols on the vertical distribution of stratocumulus microphysical quantities in southwest China, the daily variation characteristics and formation mechanism of the vertical profiles of stratocumulus microphysical characteristics in this region were described using the data of nine cloud-crossing aircraft observations over Guangxi from 10 October to 3 November 2020.
Denghui Ji, Mathias Palm, Matthias Buschmann, Kerstin Ebell, Marion Maturilli, Xiaoyu Sun, and Justus Notholt
Atmos. Chem. Phys., 25, 3889–3904, https://doi.org/10.5194/acp-25-3889-2025, https://doi.org/10.5194/acp-25-3889-2025, 2025
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Our study explores how certain aerosols, like sea salt, affect infrared heat radiation in the Arctic, potentially speeding up warming. We used advanced technology to measure aerosol composition and found that these particles grow with humidity, significantly increasing their heat-trapping effect in the infrared region, especially in winter. Our findings suggest these aerosols could be a key factor in Arctic warming, emphasizing the importance of understanding aerosols for climate prediction.
E. Johanna Horchler, Joel Alroe, Luke Harrison, Luke Cravigan, Daniel P. Harrison, and Zoran D. Ristovski
EGUsphere, https://doi.org/10.5194/egusphere-2025-465, https://doi.org/10.5194/egusphere-2025-465, 2025
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Aerosols play a role in global climate by interacting with incoming solar radiation and by taking up water vapour from the atmosphere to form clouds. Enhancing local-scale cloud cover can reduce sea surface temperatures. Coral bleaching events increased in the Great Barrier Reef (GBR) as sea surface temperatures rise. Our study found that the number of aerosols and the cloud forming ability over the GBR increased if the aerosols were transported from inland Australia rather than the ocean.
Haibiao Chen, Caiqing Yan, Liubin Huang, Lin Du, Yang Yue, Xinfeng Wang, Qingcai Chen, Mingjie Xie, Junwen Liu, Fengwen Wang, Shuhong Fang, Qiaoyun Yang, Hongya Niu, Mei Zheng, Yan Wu, and Likun Xue
Atmos. Chem. Phys., 25, 3647–3667, https://doi.org/10.5194/acp-25-3647-2025, https://doi.org/10.5194/acp-25-3647-2025, 2025
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A comprehensive understanding of the optical properties of brown carbon (BrC) is essential to accurately assess its climatic effects. Based on multi-site spectroscopic measurements, this study demonstrated the significant spatial heterogeneity in the optical and structural properties of water-soluble organic carbon (WSOC) in different regions of China and revealed factors affecting WSOC light absorption and the relationship between fluorophores and light absorption of WSOC.
Lingjun Li, Mengren Li, Xiaolong Fan, Yuping Chen, Ziyi Lin, Anqi Hou, Siqing Zhang, Ronghua Zheng, and Jinsheng Chen
Atmos. Chem. Phys., 25, 3669–3685, https://doi.org/10.5194/acp-25-3669-2025, https://doi.org/10.5194/acp-25-3669-2025, 2025
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Here, we show differences and variations in the aerosol scattering hygroscopic growth factor (f(RH)) between new particle formation (NPF) and non-NPF days and the effect of aerosol chemical compositions on f(RH) in Xiamen with in situ observations. The findings are helpful for the further understanding of aerosol hygroscopicity in a coastal city and the use of hygroscopic growth factors in models of air quality and climate change.
Roman Pohorsky, Andrea Baccarini, Natalie Brett, Brice Barret, Slimane Bekki, Gianluca Pappaccogli, Elsa Dieudonné, Brice Temime-Roussel, Barbara D'Anna, Meeta Cesler-Maloney, Antonio Donateo, Stefano Decesari, Kathy S. Law, William R. Simpson, Javier Fochesatto, Steve R. Arnold, and Julia Schmale
Atmos. Chem. Phys., 25, 3687–3715, https://doi.org/10.5194/acp-25-3687-2025, https://doi.org/10.5194/acp-25-3687-2025, 2025
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This study presents an analysis of vertical measurements of pollution in an Alaskan city during winter. It investigates the relationship between the atmospheric structure and the layering of aerosols and trace gases. Results indicate an overall very shallow surface mixing layer. The height of this layer is strongly influenced by a local shallow wind. The study also provides information on the pollution chemical composition at different altitudes, including pollution signatures from power plants.
Aoyuan Yu, Xiaojing Shen, Qianli Ma, Jiayuan Lu, Xinyao Hu, Yangmei Zhang, Quan Liu, Linlin Liang, Lei Liu, Shuo Liu, Hongfei Tong, Huizheng Che, Xiaoye Zhang, and Junying Sun
Atmos. Chem. Phys., 25, 3389–3412, https://doi.org/10.5194/acp-25-3389-2025, https://doi.org/10.5194/acp-25-3389-2025, 2025
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In this work, we utilized a volatility hygroscopicity tandem differential mobility analyzer (VH-TDMA) to investigate, for the first time, the hygroscopicity and volatility of submicron aerosols, as well as their hygroscopicity after heating, in urban Beijing during the autumn of 2023. We analyzed the size-resolved characteristics of hygroscopicity and volatility, the relationship between hygroscopic and volatile properties, and the hygroscopicity of heated submicron aerosols.
Corina Wieber, Lasse Z. Jensen, Leendert Vergeynst, Lorenz Meire, Thomas Juul-Pedersen, Kai Finster, and Tina Šantl-Temkiv
Atmos. Chem. Phys., 25, 3327–3346, https://doi.org/10.5194/acp-25-3327-2025, https://doi.org/10.5194/acp-25-3327-2025, 2025
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The Arctic region is subject to profound changes due to a warming climate. Ice-nucleating particles (INPs) in the seawater can get transported to the atmosphere and impact cloud formation. However, the sources of characteristics of INPs in the marine areas are poorly understood. We investigated the INPs in seawater from Greenlandic fjords and identified a seasonal variability, with highly active INPs originating from terrestrial sources such as glacial and soil runoff.
Silke Groß, Volker Freudenthaler, Moritz Haarig, Albert Ansmann, Carlos Toledano, David Mateos, Petra Seibert, Rodanthi-Elisavet Mamouri, Argyro Nisantzi, Josef Gasteiger, Maximilian Dollner, Anne Tipka, Manuel Schöberl, Marilena Teri, and Bernadett Weinzierl
Atmos. Chem. Phys., 25, 3191–3211, https://doi.org/10.5194/acp-25-3191-2025, https://doi.org/10.5194/acp-25-3191-2025, 2025
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Aerosols contribute to the largest uncertainties in climate change predictions. The eastern Mediterranean is a hotspot for aerosols with natural and anthropogenic contributions. We present lidar measurements performed during A-LIFE (Absorbing aerosol layers in a changing climate: aging, lifetime and dynamics) to characterize aerosols and aerosol mixtures. We extend current lidar classification and separation schemes and compare them to classification schemes using different methods.
Ludovico Di Antonio, Claudia Di Biagio, Paola Formenti, Aline Gratien, Vincent Michoud, Christopher Cantrell, Astrid Bauville, Antonin Bergé, Mathieu Cazaunau, Servanne Chevaillier, Manuela Cirtog, Patrice Coll, Barbara D'Anna, Joel F. de Brito, David O. De Haan, Juliette R. Dignum, Shravan Deshmukh, Olivier Favez, Pierre-Marie Flaud, Cecile Gaimoz, Lelia N. Hawkins, Julien Kammer, Brigitte Language, Franck Maisonneuve, Griša Močnik, Emilie Perraudin, Jean-Eudes Petit, Prodip Acharja, Laurent Poulain, Pauline Pouyes, Eva Drew Pronovost, Véronique Riffault, Kanuri I. Roundtree, Marwa Shahin, Guillaume Siour, Eric Villenave, Pascal Zapf, Gilles Foret, Jean-François Doussin, and Matthias Beekmann
Atmos. Chem. Phys., 25, 3161–3189, https://doi.org/10.5194/acp-25-3161-2025, https://doi.org/10.5194/acp-25-3161-2025, 2025
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The spectral complex refractive index (CRI) and single scattering albedo were retrieved from submicron aerosol measurements at three sites within the greater Paris area during the ACROSS field campaign (June–July 2022). Measurements revealed urban emission impact on surrounding areas. CRI full period averages at 520 nm were 1.41 – 0.037i (urban), 1.52 – 0.038i (peri-urban), and 1.50 – 0.025i (rural). Organic aerosols dominated the aerosol mass and contributed up to 22 % of absorption at 370 nm.
Leah D. Gibson, Ezra J. T. Levin, Ethan Emerson, Nick Good, Anna Hodshire, Gavin McMeeking, Kate Patterson, Bryan Rainwater, Tom Ramin, and Ben Swanson
Atmos. Chem. Phys., 25, 2745–2762, https://doi.org/10.5194/acp-25-2745-2025, https://doi.org/10.5194/acp-25-2745-2025, 2025
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From fall 2021 to summer 2023, SAIL-Net, a network of six aerosol measurement nodes, was deployed in the East River watershed (Colorado, USA) to study aerosol variability across space and time in mountainous terrain. We found that aerosol variability is influenced by elevation differences, with the most representative site in the region changing seasonally, suggesting aerosol spatial variability also varies seasonally. This work offers a blueprint for future studies in other mountainous regions.
Tahereh Alinejadtabrizi, Yi Huang, Francisco Lang, Steven Siems, Michael Manton, Luis Ackermann, Melita Keywood, Ruhi Humphries, Paul Krummel, Alastair Williams, and Greg Ayers
Atmos. Chem. Phys., 25, 2631–2648, https://doi.org/10.5194/acp-25-2631-2025, https://doi.org/10.5194/acp-25-2631-2025, 2025
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Clouds over the Southern Ocean are crucial to Earth's energy balance, but understanding the factors that control them is complex. Our research examines how weather patterns affect tiny particles called cloud condensation nuclei (CCN), which influence cloud properties. Using data from Kennaook / Cape Grim, we found that winter air from Antarctica brings cleaner conditions with lower CCN, while summer patterns from Australia transport more particles. Precipitation also helps reduce CCN in winter.
Hengjia Ou, Mingfu Cai, Yongyun Zhang, Xue Ni, Baoling Liang, Qibin Sun, Shixin Mai, Cuizhi Sun, Shengzhen Zhou, Haichao Wang, Jiaren Sun, and Jun Zhao
Atmos. Chem. Phys., 25, 2495–2513, https://doi.org/10.5194/acp-25-2495-2025, https://doi.org/10.5194/acp-25-2495-2025, 2025
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Two shipborne observations in the South China Sea (SCS) in summer and winter 2021 were conducted. Our study found aerosol hygroscopicity is higher in the SCS in summer than winter, with significant influences from various terrestrial air masses. Aerosol size distribution had a stronger effect on activation ratio than aerosol hygroscopicity in summer and vice versa in winter. Our study provides valuable information to enhance our understanding of cloud condensation nuclei activities in the SCS.
Tinghan Zhang, Ximeng Qi, Janne Lampilahti, Liangduo Chen, Xuguang Chi, Wei Nie, Xin Huang, Zehao Zou, Wei Du, Tom Kokkonen, Tuukka Petäjä, Katrianne Lehtipalo, Veli-Matti Kerminen, Aijun Ding, and Markku Kulmala
EGUsphere, https://doi.org/10.5194/egusphere-2024-3370, https://doi.org/10.5194/egusphere-2024-3370, 2025
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By comparing air ions at two “flagship” sites —the SMEAR II site in the boreal forest of Finland and the SORPES site in a megacity in eastern China—we characterized ion concentrations and their roles in new particle formation (NPF) across contrasting environments. The ion-induced fraction was much higher in clean areas. However, earlier activation of charged particles and high ion-induced fraction during quiet NPF at SORPES imply a non-negligible role for ion-induced NPF in polluted areas.
Jinghao Zhai, Yin Zhang, Pengfei Liu, Yujie Zhang, Antai Zhang, Yaling Zeng, Baohua Cai, Jingyi Zhang, Chunbo Xing, Honglong Yang, Xiaofei Wang, Jianhuai Ye, Chen Wang, Tzung-May Fu, Lei Zhu, Huizhong Shen, Shu Tao, and Xin Yang
EGUsphere, https://doi.org/10.5194/egusphere-2025-463, https://doi.org/10.5194/egusphere-2025-463, 2025
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Our findings show that BrC's optical properties vary by source. Secondary BrC from ozone pollution had the lowest absorption but highest wavelength dependence, while BrC from biomass combustion had the highest absorption with the lowest wavelength dependence. Molecular analysis indicated that CHON species from biomass burning had the strongest light absorption. These insights enhance the accuracy of climate models by highlighting source-specific optical properties of BrC.
Irena Ježek Brecelj, Asta Gregorič, Lucijan Zgonik, Tjaša Rutar, Matic Ivančič, Balint Alfoldy, Griša Močnik, and Martin Rigler
EGUsphere, https://doi.org/10.5194/egusphere-2024-3553, https://doi.org/10.5194/egusphere-2024-3553, 2025
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Following a major car industry scandal involving diesel emissions tests, Europe introduced new testing procedures. However, concerns remained about their effectiveness. Our independent study examined real-world vehicle emissions and revealed encouraging findings: modern diesel cars perform as well as, or even better than, gasoline cars in terms of nitrogen oxides emissions. We found the same pattern for soot particles, challenging common perceptions about diesel's environmental impact.
Bighnaraj Sarangi, Darrel Baumgardner, Ana Isabel Calvo, Benjamin Bolaños-Rosero, Roberto Fraile, Alberto Rodríguez-Fernández, Delia Fernández-González, Carlos Blanco-Alegre, Cátia Gonçalves, Estela D. Vicente, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 25, 843–865, https://doi.org/10.5194/acp-25-843-2025, https://doi.org/10.5194/acp-25-843-2025, 2025
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Measurements of fluorescing aerosol particle properties have been made during two major African dust events, one over the island of Puerto Rico and the other over the city of León, Spain. The measurements were made with two wideband integrated bioaerosol spectrometers. A significant change in the background aerosol properties, at both locations, is observed when the dust is in the respective regions.
Lijing Chen, Lei Zhang, Yong She, Zhaoliang Zeng, Yu Zheng, Biao Tian, Wenqian Zhang, Zhaohui Liu, Huizheng Che, and Minghu Ding
Atmos. Chem. Phys., 25, 727–739, https://doi.org/10.5194/acp-25-727-2025, https://doi.org/10.5194/acp-25-727-2025, 2025
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Aerosol optical depth (AOD) at Zhongshan Station varies seasonally, with lower values in summer and higher values in winter. Winter and spring AOD increases due to reduced fine-mode particles, while summer and autumn increases are linked to particle growth. Diurnal AOD variation correlates positively with temperature but negatively with wind speed and humidity. Backward trajectories show that aerosols on high-AOD (low-AOD) days primarily originate from the ocean (interior Antarctica).
Shravan Deshmukh, Laurent Poulain, Birgit Wehner, Silvia Henning, Jean-Eudes Petit, Pauline Fombelle, Olivier Favez, Hartmut Herrmann, and Mira Pöhlker
Atmos. Chem. Phys., 25, 741–758, https://doi.org/10.5194/acp-25-741-2025, https://doi.org/10.5194/acp-25-741-2025, 2025
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Aerosol hygroscopicity has been investigated at a sub-urban site in Paris; analysis shows the sub-saturated regime's measured hygroscopicity and the chemically derived hygroscopic growth, shedding light on the large effect of external particle mixing and its influence on predicting hygroscopicity.
Takeshi Kinase, Fumikazu Taketani, Masayuki Takigawa, Chunmao Zhu, Yongwon Kim, Petr Mordovskoi, and Yugo Kanaya
Atmos. Chem. Phys., 25, 143–156, https://doi.org/10.5194/acp-25-143-2025, https://doi.org/10.5194/acp-25-143-2025, 2025
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Boreal forest wildfires in interior Alaska represent an important black carbon (BC) source for the Arctic and surrounding regions. We observed BC and carbon monoxide (CO) concentrations in the Poker Flat Research Range since 2016 and found a positive correlation between the observed BC / ∆CO ratio and fire radiative power (FRP) observed in Alaska and Canada. Our finding suggests the BC emission factor and/or inventory could be potentially improved by using FRP.
Meredith Dournaux, Pierre Tulet, Joris Pianezze, Jérome Brioude, Jean-Marc Metzger, and Melilotus Thyssen
EGUsphere, https://doi.org/10.5194/egusphere-2024-3747, https://doi.org/10.5194/egusphere-2024-3747, 2025
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Aerosol measurements collected during six oceanographic campaigns carried out in 2021 and 2023 in the southwest Indian Ocean are presented and analyzed in this paper. The results highlight a large variability in the aerosol concentration, size and water vapor affinity depending on in-situ conditions and air mass transport over the ocean. Marine aerosol chemical composition is highly variable over this region, and should be considered to better study their impacts on regional weather and climate.
Erin N. Raif, Sarah L. Barr, Mark D. Tarn, James B. McQuaid, Martin I. Daily, Steven J. Abel, Paul A. Barrett, Keith N. Bower, Paul R. Field, Kenneth S. Carslaw, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 14045–14072, https://doi.org/10.5194/acp-24-14045-2024, https://doi.org/10.5194/acp-24-14045-2024, 2024
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Ice-nucleating particles (INPs) allow ice to form in clouds at temperatures warmer than −35°C. We measured INP concentrations over the Norwegian and Barents seas in weather events where cold air is ejected from the Arctic. These concentrations were among the highest measured in the Arctic. It is likely that the INPs were transported to the Arctic from distant regions. These results show it is important to consider hemispheric-scale INP processes to understand INP concentrations in the Arctic.
Fernando Rejano, Andrea Casans, Marta Via, Juan Andrés Casquero-Vera, Sonia Castillo, Hassan Lyamani, Alberto Cazorla, Elisabeth Andrews, Daniel Pérez-Ramírez, Andrés Alastuey, Francisco Javier Gómez-Moreno, Lucas Alados-Arboledas, Francisco José Olmo, and Gloria Titos
Atmos. Chem. Phys., 24, 13865–13888, https://doi.org/10.5194/acp-24-13865-2024, https://doi.org/10.5194/acp-24-13865-2024, 2024
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This study provides valuable insights to improve cloud condensation nuclei (CCN) estimations at a high-altitude remote site which is influenced by nearby urban pollution. Understanding the factors that affect CCN estimations is essential to improve the CCN data coverage worldwide and assess aerosol–cloud interactions on a global scale. This is crucial for improving climate models, since aerosol–cloud interactions are the most important source of uncertainty in climate projections.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Junying Sun, Ye Kuang, Paola Formenti, and Steven G. Howell
Atmos. Chem. Phys., 24, 13849–13864, https://doi.org/10.5194/acp-24-13849-2024, https://doi.org/10.5194/acp-24-13849-2024, 2024
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Using airborne measurements over the southeast Atlantic Ocean, we examined how much moisture aerosols take up during Africa’s biomass burning season. Our study revealed the important role of organic aerosols and introduced a predictive model for moisture uptake, accounting for organics, sulfate, and black carbon, summarizing results from various campaigns. These findings improve our understanding of aerosol–moisture interactions and their radiative effects in this climatically critical region.
Mary C. Robinson, Kaitlin Schueth, and Karin Ardon-Dryer
Atmos. Chem. Phys., 24, 13733–13750, https://doi.org/10.5194/acp-24-13733-2024, https://doi.org/10.5194/acp-24-13733-2024, 2024
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On 26 February 2023, New Mexico and West Texas were impacted by a severe dust storm. To analyze this storm, 28 meteorological stations and 19 PM2.5 and PM10 stations were used. Dust particles were in the air for 16 h, and dust storm conditions lasted for up to 120 min. Hourly PM2.5 and PM10 concentrations were up to 518 and 9983 µg m−3, respectively. For Lubbock, Texas, the maximum PM2.5 concentrations were the highest ever recorded.
Jerome D. Fast, Adam C. Varble, Fan Mei, Mikhail Pekour, Jason Tomlinson, Alla Zelenyuk, Art J. Sedlacek III, Maria Zawadowicz, and Louisa Emmons
Atmos. Chem. Phys., 24, 13477–13502, https://doi.org/10.5194/acp-24-13477-2024, https://doi.org/10.5194/acp-24-13477-2024, 2024
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Aerosol property measurements recently collected on the ground and by a research aircraft in central Argentina during the Cloud, Aerosol, and Complex Terrain Interactions (CACTI) campaign exhibit large spatial and temporal variability. These measurements coupled with coincident meteorological information provide a valuable data set needed to evaluate and improve model predictions of aerosols in a traditionally data-sparse region of South America.
Yifan Yang, Thomas Müller, Laurent Poulain, Samira Atabakhsh, Bruna A. Holanda, Jens Voigtländer, Shubhi Arora, and Mira L. Pöhlker
EGUsphere, https://doi.org/10.5194/egusphere-2024-3539, https://doi.org/10.5194/egusphere-2024-3539, 2024
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Black carbon (BC) is the major atmospheric aerosol that can absorb light and influence climate. We measured the physical properties of BC at a background site in Germany. In summer, BC particles were smaller and the mixture with other atmospheric components occurred during the daytime. In winter, emissions from residential heating significantly influenced BC's properties. Understanding these characteristics of BC can help improve aerosol optics simulation accuracy.
Julika Zinke, Gabriel Pereira Freitas, Rachel Ann Foster, Paul Zieger, Ernst Douglas Nilsson, Piotr Markuszewski, and Matthew Edward Salter
Atmos. Chem. Phys., 24, 13413–13428, https://doi.org/10.5194/acp-24-13413-2024, https://doi.org/10.5194/acp-24-13413-2024, 2024
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Bioaerosols, which can influence climate and human health, were studied in the Baltic Sea. In May and August 2021, we used a sea spray simulation chamber during two ship-based campaigns to collect and measure these aerosols. We found that microbes were enriched in air compared to seawater. Bacterial diversity was analysed using DNA sequencing. Our methods provided consistent estimates of microbial emission fluxes, aligning with previous studies.
Chimurkar Navinya, Taveen Singh Kapoor, Gupta Anurag, Chandra Venkataraman, Harish C. Phuleria, and Rajan K. Chakrabarty
Atmos. Chem. Phys., 24, 13285–13297, https://doi.org/10.5194/acp-24-13285-2024, https://doi.org/10.5194/acp-24-13285-2024, 2024
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Brown carbon (BrC) aerosols show an order-of-magnitude variation in their light absorption strength. Our understanding of BrC from real-world biomass burning remains limited, complicating the determination of its radiative impact. Our study reports absorption properties of BrC emitted from four major biomass burning sources using field measurements in India. It develops an absorption parameterization for BrC and examines the spatial variability in BrC's absorption strength across India.
Olga B. Popovicheva, Marina A. Chichaeva, Nikolaos Evangeliou, Sabine Eckhardt, Evangelia Diapouli, and Nikolay S. Kasimov
EGUsphere, https://doi.org/10.5194/egusphere-2024-3124, https://doi.org/10.5194/egusphere-2024-3124, 2024
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High-quality measurements of light-absorbing carbon were performed at the polar aerosol station "Island Bely” (Western Siberian Arctic) from 2019 to 2022. The maximum light absorption coefficients were seen in summer due to gas flaring contribution, which is the most significant source in the region. However, the increasing Siberian wildfires had a special share in carbon contribution to this high Arctic station with a persistent smoke layer extending over the whole troposphere in summer.
Rafael Stern, Joel F. de Brito, Samara Carbone, Luciana Varanda Rizzo, Jonathan Daniel Muller, and Paulo Artaxo
EGUsphere, https://doi.org/10.5194/egusphere-2024-3339, https://doi.org/10.5194/egusphere-2024-3339, 2024
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Our work reveals the impact of forest fires on climate. We found that particles related to direct emissions from fires, beyond the well-known effect of absorbing light and thus heating the atmosphere, are also very efficient in scattering light, which causes an atmospheric cooling effect. In our remote study site, most of the particles presented a different chemical composition then particles directly emitted by the fires, but those were the main responsible for total light extinction.
Sami D. Harni, Minna Aurela, Sanna Saarikoski, Jarkko V. Niemi, Harri Portin, Hanna Manninen, Ville Leinonen, Pasi Aalto, Phil K. Hopke, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 24, 12143–12160, https://doi.org/10.5194/acp-24-12143-2024, https://doi.org/10.5194/acp-24-12143-2024, 2024
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In this study, particle number size distribution data were used in a novel way in positive matrix factorization analysis to find aerosol source profiles in the area. Measurements were made in Helsinki at a street canyon and urban background sites between February 2015 and June 2019. Five different aerosol sources were identified. These sources underline the significance of traffic-related emissions in urban environments despite recent improvements in emission reduction technologies.
Natalie G. Ratcliffe, Claire L. Ryder, Nicolas Bellouin, Stephanie Woodward, Anthony Jones, Ben Johnson, Lisa-Maria Wieland, Maximilian Dollner, Josef Gasteiger, and Bernadett Weinzierl
Atmos. Chem. Phys., 24, 12161–12181, https://doi.org/10.5194/acp-24-12161-2024, https://doi.org/10.5194/acp-24-12161-2024, 2024
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Large mineral dust particles are more abundant in the atmosphere than expected and have different impacts on the environment than small particles, which are better represented in climate models. We use aircraft measurements to assess a climate model representation of large-dust transport. We find that the model underestimates the amount of large dust at all stages of transport and that fast removal of the large particles increases this underestimation with distance from the Sahara.
Sergio Rodríguez and Jessica López-Darias
Atmos. Chem. Phys., 24, 12031–12053, https://doi.org/10.5194/acp-24-12031-2024, https://doi.org/10.5194/acp-24-12031-2024, 2024
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Extreme Saharan dust events expanded northward to the Atlantic and Europe, prompting record-breaking PM10 and PM2.5 events. These episodes are caused by low-to-high dipole meteorology during hemispheric anomalies characterized by subtropical anticyclones shifting to higher latitudes, anomalous low pressures beyond the tropics and amplified Rossby waves. Extreme dust events occur in a paradoxical context of a multidecadal decrease in dust emissions, a topic that requires further investigation.
Valeria Mardoñez-Balderrama, Griša Močnik, Marco Pandolfi, Robin L. Modini, Fernando Velarde, Laura Renzi, Angela Marinoni, Jean-Luc Jaffrezo, Isabel Moreno R., Diego Aliaga, Federico Bianchi, Claudia Mohr, Martin Gysel-Beer, Patrick Ginot, Radovan Krejci, Alfred Wiedensohler, Gaëlle Uzu, Marcos Andrade, and Paolo Laj
Atmos. Chem. Phys., 24, 12055–12077, https://doi.org/10.5194/acp-24-12055-2024, https://doi.org/10.5194/acp-24-12055-2024, 2024
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Levels of black carbon (BC) are scarcely reported in the Southern Hemisphere, especially in high-altitude conditions. This study provides insight into the concentration level, variability, and optical properties of BC in La Paz and El Alto and at the Chacaltaya Global Atmosphere Watch Station. Two methods of source apportionment of absorption were tested and compared showing traffic as the main contributor to absorption in the urban area, in addition to biomass and open waste burning.
Krishnakant Budhavant, Mohanan Remani Manoj, Hari Ram Chandrika Rajendran Nair, Samuel Mwaniki Gaita, Henry Holmstrand, Abdus Salam, Ahmed Muslim, Sreedharan Krishnakumari Satheesh, and Örjan Gustafsson
Atmos. Chem. Phys., 24, 11911–11925, https://doi.org/10.5194/acp-24-11911-2024, https://doi.org/10.5194/acp-24-11911-2024, 2024
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The South Asian Pollution Experiment 2018 used access to three strategically located receptor observatories. Observational constraints revealed opposing trends in the mass absorption cross sections of black carbon (BC MAC) and brown carbon (BrC MAC) during long-range transport. Models estimating the climate effects of BC aerosols may have underestimated the ambient BC MAC over distant receptor areas, leading to discrepancies in aerosol absorption predicted by observation-constrained models.
Abigail S. Williams, Jeramy L. Dedrick, Lynn M. Russell, Florian Tornow, Israel Silber, Ann M. Fridlind, Benjamin Swanson, Paul J. DeMott, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 24, 11791–11805, https://doi.org/10.5194/acp-24-11791-2024, https://doi.org/10.5194/acp-24-11791-2024, 2024
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The measured aerosol size distribution modes reveal distinct properties characteristic of cold-air outbreaks in the Norwegian Arctic. We find higher sea spray number concentrations, smaller Hoppel minima, lower effective supersaturations, and accumulation-mode particle scavenging during cold-air outbreaks. These results advance our understanding of cold-air outbreak aerosol–cloud interactions in order to improve their accurate representation in models.
Franziska Vogel, Michael P. Adams, Larissa Lacher, Polly B. Foster, Grace C. E. Porter, Barbara Bertozzi, Kristina Höhler, Julia Schneider, Tobias Schorr, Nsikanabasi S. Umo, Jens Nadolny, Zoé Brasseur, Paavo Heikkilä, Erik S. Thomson, Nicole Büttner, Martin I. Daily, Romy Fösig, Alexander D. Harrison, Jorma Keskinen, Ulrike Proske, Jonathan Duplissy, Markku Kulmala, Tuukka Petäjä, Ottmar Möhler, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 11737–11757, https://doi.org/10.5194/acp-24-11737-2024, https://doi.org/10.5194/acp-24-11737-2024, 2024
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Primary ice formation in clouds strongly influences their properties; hence, it is important to understand the sources of ice-nucleating particles (INPs) and their variability. We present 2 months of INP measurements in a Finnish boreal forest using a new semi-autonomous INP counting device based on gas expansion. These results show strong variability in INP concentrations, and we present a case that the INPs we observe are, at least some of the time, of biological origin.
Rebecca Dischl, Daniel Sauer, Christiane Voigt, Theresa Harlaß, Felicitas Sakellariou, Raphael Märkl, Ulrich Schumann, Monika Scheibe, Stefan Kaufmann, Anke Roiger, Andreas Dörnbrack, Charles Renard, Maxime Gauthier, Peter Swann, Paul Madden, Darren Luff, Mark Johnson, Denise Ahrens, Reetu Sallinen, Tobias Schripp, Georg Eckel, Uwe Bauder, and Patrick Le Clercq
Atmos. Chem. Phys., 24, 11255–11273, https://doi.org/10.5194/acp-24-11255-2024, https://doi.org/10.5194/acp-24-11255-2024, 2024
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In-flight measurements of aircraft emissions burning 100 % sustainable aviation fuel (SAF) show reduced particle number concentrations up to 41 % compared to conventional jet fuel. Particle emissions are dependent on engine power setting, flight altitude, and fuel composition. Engine models show a good correlation with measurement results. Future increased prevalence of SAF can positively influence the climate impact of aviation.
Zoé Brasseur, Julia Schneider, Janne Lampilahti, Ville Vakkari, Victoria A. Sinclair, Christina J. Williamson, Carlton Xavier, Dmitri Moisseev, Markus Hartmann, Pyry Poutanen, Markus Lampimäki, Markku Kulmala, Tuukka Petäjä, Katrianne Lehtipalo, Erik S. Thomson, Kristina Höhler, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 24, 11305–11332, https://doi.org/10.5194/acp-24-11305-2024, https://doi.org/10.5194/acp-24-11305-2024, 2024
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Ice-nucleating particles (INPs) strongly influence the formation of clouds by initiating the formation of ice crystals. However, very little is known about the vertical distribution of INPs in the atmosphere. Here, we present aircraft measurements of INP concentrations above the Finnish boreal forest. Results show that near-surface INPs are efficiently transported and mixed within the boundary layer and occasionally reach the free troposphere.
Piotr Markuszewski, E. Douglas Nilsson, Julika Zinke, E. Monica Mårtensson, Matthew Salter, Przemysław Makuch, Małgorzata Kitowska, Iwona Niedźwiecka-Wróbel, Violetta Drozdowska, Dominik Lis, Tomasz Petelski, Luca Ferrero, and Jacek Piskozub
Atmos. Chem. Phys., 24, 11227–11253, https://doi.org/10.5194/acp-24-11227-2024, https://doi.org/10.5194/acp-24-11227-2024, 2024
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Our research provides new insights into the study of sea spray aerosol (SSA) emissions in the Baltic Sea and North Atlantic. We observed that SSA flux is suppressed during increased marine biological activity in the Baltic Sea. At the same time, the influence of wave age showed higher SSA emissions in the Baltic Sea for younger waves compared to the Atlantic Ocean. These insights underscore the complex interplay between biological activity and physical dynamics in regulating SSA emissions.
Heather Guy, Andrew S. Martin, Erik Olson, Ian M. Brooks, and Ryan R. Neely III
Atmos. Chem. Phys., 24, 11103–11114, https://doi.org/10.5194/acp-24-11103-2024, https://doi.org/10.5194/acp-24-11103-2024, 2024
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Aerosol particles impact cloud properties which influence Greenland Ice Sheet melt. Understanding the aerosol population that interacts with clouds is important for constraining future melt. Measurements of aerosols at cloud height over Greenland are rare, and surface measurements are often used to investigate cloud–aerosol interactions. We use a tethered balloon to measure aerosols up to cloud base and show that surface measurements are often not equivalent to those just below the cloud.
Kouji Adachi, Jack E. Dibb, Joseph M. Katich, Joshua P. Schwarz, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Jeff Peischl, Christopher D. Holmes, and James Crawford
Atmos. Chem. Phys., 24, 10985–11004, https://doi.org/10.5194/acp-24-10985-2024, https://doi.org/10.5194/acp-24-10985-2024, 2024
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We examined aerosol particles from wildfires and identified tarballs (TBs) from the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) campaign. This study reveals the compositions, abundance, sizes, and mixing states of TBs and shows that TBs formed as the smoke aged for up to 5 h. This study provides measurements of TBs from various biomass-burning events and ages, enhancing our knowledge of TB emissions and our understanding of their climate impact.
Jia Sun, Markus Hermann, Kay Weinhold, Maik Merkel, Wolfram Birmili, Yifan Yang, Thomas Tuch, Harald Flentje, Björn Briel, Ludwig Ries, Cedric Couret, Michael Elsasser, Ralf Sohmer, Klaus Wirtz, Frank Meinhardt, Maik Schütze, Olaf Bath, Bryan Hellack, Veli-Matti Kerminen, Markku Kulmala, Nan Ma, and Alfred Wiedensohler
Atmos. Chem. Phys., 24, 10667–10687, https://doi.org/10.5194/acp-24-10667-2024, https://doi.org/10.5194/acp-24-10667-2024, 2024
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We investigated the characteristics of new particle formation (NPF) for various environments from urban background to high Alpine and the impacts of NPF on cloud condensation nuclei and aerosol radiative forcing. NPF features differ between site categories, implying the crucial role of local environmental factors such as the degree of emissions and meteorological conditions. The results also underscore the importance of local environments when assessing the impact of NPF on climate in models.
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Cazorla, A., Bahadur, R., Suski, K. J., Cahill, J. F., Chand, D., Schmid, B., Ramanathan, V., and Prather, K. A.: Relating aerosol absorption due to soot, organic carbon, and dust to emission sources determined from in-situ chemical measurements, Atmos. Chem. Phys., 13, 9337–9350, https://doi.org/10.5194/acp-13-9337-2013, 2013.
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Short summary
Measurements of size-dependent aerosol optical properties at visible wavelengths made during the 2010 CARES study are reported on, with a special focus on the characterization of supermicron particles. The relationships with and dependence upon particle composition, particle size, photochemical aging, water uptake and heating are discussed, along with broader implications of these in situ measurements for the interpretation of remote sensing products.
Measurements of size-dependent aerosol optical properties at visible wavelengths made during the...
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