Articles | Volume 22, issue 22
https://doi.org/10.5194/acp-22-14971-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-22-14971-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Nov 2022
Research article |
| 24 Nov 2022
Chromophores and chemical composition of brown carbon characterized at an urban kerbside by excitation–emission spectroscopy and mass spectrometry
Feng Jiang
CORRESPONDING AUTHOR
Institute of Meteorology and Climate Research, Karlsruhe Institute of
Technology, 76344 Eggenstein-Leopoldshafen, Germany
Institute of Applied Geosciences, Working Group for Environmental
Mineralogy and Environmental System Analysis, Karlsruhe Institute of
Technology, 76131 Karlsruhe, Germany
Junwei Song
Institute of Meteorology and Climate Research, Karlsruhe Institute of
Technology, 76344 Eggenstein-Leopoldshafen, Germany
Institute of Applied Geosciences, Working Group for Environmental
Mineralogy and Environmental System Analysis, Karlsruhe Institute of
Technology, 76131 Karlsruhe, Germany
Jonas Bauer
Institute of Applied Geosciences, Working Group for Environmental
Mineralogy and Environmental System Analysis, Karlsruhe Institute of
Technology, 76131 Karlsruhe, Germany
Linyu Gao
Institute of Meteorology and Climate Research, Karlsruhe Institute of
Technology, 76344 Eggenstein-Leopoldshafen, Germany
Institute of Applied Geosciences, Working Group for Environmental
Mineralogy and Environmental System Analysis, Karlsruhe Institute of
Technology, 76131 Karlsruhe, Germany
Magdalena Vallon
Institute of Meteorology and Climate Research, Karlsruhe Institute of
Technology, 76344 Eggenstein-Leopoldshafen, Germany
Reiner Gebhardt
Institute of Geography and Geoecology, Karlsruhe Institute of
Technology, Reinhard-Baumeister-Platz 1, 76131 Karlsruhe, Germany
Thomas Leisner
Institute of Meteorology and Climate Research, Karlsruhe Institute of
Technology, 76344 Eggenstein-Leopoldshafen, Germany
Institute of Environmental Physics, Heidelberg University, 69120
Heidelberg, Germany
Stefan Norra
Institute of Applied Geosciences, Working Group for Environmental
Mineralogy and Environmental System Analysis, Karlsruhe Institute of
Technology, 76131 Karlsruhe, Germany
Institute of Environmental Sciences and Geography, Chair of Soil
Science and Geoecology, University of Potsdam, Karl-Liebknecht-Strasse 24/25, 14476 Potsdam, Germany
Harald Saathoff
CORRESPONDING AUTHOR
Institute of Meteorology and Climate Research, Karlsruhe Institute of
Technology, 76344 Eggenstein-Leopoldshafen, Germany
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Julia Schneider, Kristina Höhler, Paavo Heikkilä, Jorma Keskinen, Barbara Bertozzi, Pia Bogert, Tobias Schorr, Nsikanabasi Silas Umo, Franziska Vogel, Zoé Brasseur, Yusheng Wu, Simo Hakala, Jonathan Duplissy, Dmitri Moisseev, Markku Kulmala, Michael P. Adams, Benjamin J. Murray, Kimmo Korhonen, Liqing Hao, Erik S. Thomson, Dimitri Castarède, Thomas Leisner, Tuukka Petäjä, and Ottmar Möhler
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Robert Wagner, Baptiste Testa, Michael Höpfner, Alexei Kiselev, Ottmar Möhler, Harald Saathoff, Jörn Ungermann, and Thomas Leisner
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Michael Krayer, Agathe Chouippe, Markus Uhlmann, Jan Dušek, and Thomas Leisner
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Alexei Korolev and Thomas Leisner
Atmos. Chem. Phys., 20, 11767–11797, https://doi.org/10.5194/acp-20-11767-2020, https://doi.org/10.5194/acp-20-11767-2020, 2020
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Isabelle Steinke, Naruki Hiranuma, Roger Funk, Kristina Höhler, Nadine Tüllmann, Nsikanabasi Silas Umo, Peter G. Weidler, Ottmar Möhler, and Thomas Leisner
Atmos. Chem. Phys., 20, 11387–11397, https://doi.org/10.5194/acp-20-11387-2020, https://doi.org/10.5194/acp-20-11387-2020, 2020
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In this study, we highlight the potential impact of particles from certain terrestrial sources on the formation of ice crystals in clouds. In particular, we focus on biogenic particles consisting of various organic compounds, which makes it very difficult to predict the ice nucleation properties of complex ambient particles. We find that these ambient particles are often more ice active than individual components.
Benjamin W. Clouser, Kara D. Lamb, Laszlo C. Sarkozy, Jan Habig, Volker Ebert, Harald Saathoff, Ottmar Möhler, and Elisabeth J. Moyer
Atmos. Chem. Phys., 20, 1089–1103, https://doi.org/10.5194/acp-20-1089-2020, https://doi.org/10.5194/acp-20-1089-2020, 2020
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anomalous supersaturationin conditions similar to the real atmosphere.
Xiaoli Shen, Heike Vogel, Bernhard Vogel, Wei Huang, Claudia Mohr, Ramakrishna Ramisetty, Thomas Leisner, André S. H. Prévôt, and Harald Saathoff
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Tasha Aylett, James S. A. Brooke, Alexander D. James, Mario Nachbar, Denis Duft, Thomas Leisner, and John M. C. Plane
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Wei Huang, Harald Saathoff, Xiaoli Shen, Ramakrishna Ramisetty, Thomas Leisner, and Claudia Mohr
Atmos. Chem. Phys., 19, 11687–11700, https://doi.org/10.5194/acp-19-11687-2019, https://doi.org/10.5194/acp-19-11687-2019, 2019
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Martin Schnaiter, Claudia Linke, Inas Ibrahim, Alexei Kiselev, Fritz Waitz, Thomas Leisner, Stefan Norra, and Till Rehm
Atmos. Chem. Phys., 19, 10829–10844, https://doi.org/10.5194/acp-19-10829-2019, https://doi.org/10.5194/acp-19-10829-2019, 2019
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When combustion particles are deposited to the ground, they darken Earth's snow and ice surfaces by even tiny quantities. This darkening reduces the back reflection of sunlight and induces an additional climate warming. Particles from fresh snow samples were investigated according to their light absorption strength. Enhanced absorption was found in the snow that cannot fully be attributed to combustion particles. Dust and biogenic matter are likely the cause of this additional snow darkening.
Nsikanabasi Silas Umo, Robert Wagner, Romy Ullrich, Alexei Kiselev, Harald Saathoff, Peter G. Weidler, Daniel J. Cziczo, Thomas Leisner, and Ottmar Möhler
Atmos. Chem. Phys., 19, 8783–8800, https://doi.org/10.5194/acp-19-8783-2019, https://doi.org/10.5194/acp-19-8783-2019, 2019
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Annually, over 600 Tg of coal fly ash (CFA) is produced; a significant proportion of this amount is injected into the atmosphere, which could significantly contribute to heterogeneous ice formation in clouds. This study presents an improved understanding of CFA particles' behaviour in forming ice in clouds, especially when exposed to lower temperatures before being re-circulated in the upper troposphere or entrained into the lower troposphere.
Zamin A. Kanji, Ryan C. Sullivan, Monika Niemand, Paul J. DeMott, Anthony J. Prenni, Cédric Chou, Harald Saathoff, and Ottmar Möhler
Atmos. Chem. Phys., 19, 5091–5110, https://doi.org/10.5194/acp-19-5091-2019, https://doi.org/10.5194/acp-19-5091-2019, 2019
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The ice nucleation ability of two natural desert dusts coated with a proxy of secondary organic aerosol is presented for temperatures and relative humidity conditions relevant for mixed-phase clouds. We find that at the tested conditions, there is no effect on the ice nucleation ability of the particles due to the organic coating. Furthermore, the two dust samples do not show variability within measurement uncertainty. Particle size and surface area may play a role in any difference observed.
Xiaoli Shen, Harald Saathoff, Wei Huang, Claudia Mohr, Ramakrishna Ramisetty, and Thomas Leisner
Atmos. Meas. Tech., 12, 2219–2240, https://doi.org/10.5194/amt-12-2219-2019, https://doi.org/10.5194/amt-12-2219-2019, 2019
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Based on single-particle mass spectra from field measurements in the upper Rhine valley, we identified characteristic particle classes and estimated their mass contributions without the need of a reference instrument in the field. Our study provides a good example for quantitative interpretation of single-particle data. Together with the complimentary results from bulk measurements, we have shown how a better understanding of the mixing state of ambient aerosol particles can be achieved.
Mario Nachbar, Henrike Wilms, Denis Duft, Tasha Aylett, Kensei Kitajima, Takuya Majima, John M. C. Plane, Markus Rapp, and Thomas Leisner
Atmos. Chem. Phys., 19, 4311–4322, https://doi.org/10.5194/acp-19-4311-2019, https://doi.org/10.5194/acp-19-4311-2019, 2019
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Polar mesospheric clouds (PMC) are water ice clouds forming on nanoparticles in the polar summer mesopause. We investigate the impact of solar radiation on PMC formation in the laboratory. We show that Mie theory calculations combined with an equilibrium temperature model presented in this work predict the warming of the particles very well. Using this model we demonstrate that the impact of solar radiation on ice particle formation is significantly lower than previously assumed.
Denis Duft, Mario Nachbar, and Thomas Leisner
Atmos. Chem. Phys., 19, 2871–2879, https://doi.org/10.5194/acp-19-2871-2019, https://doi.org/10.5194/acp-19-2871-2019, 2019
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How ice particles form in polar mesospheric clouds is still a challenging question. We measured the water adsorption and onset conditions for ice growth on meteoric smoke analogue particles in the laboratory. We find that the particles activate by growth of amorphous ice and at much warmer conditions than previously assumed, affirming meteoric smoke as likely seeds in mesospheric ice clouds. We propose an ice-activation model and show that the particle charge does not play a significant role.
Emma Järvinen, Olivier Jourdan, David Neubauer, Bin Yao, Chao Liu, Meinrat O. Andreae, Ulrike Lohmann, Manfred Wendisch, Greg M. McFarquhar, Thomas Leisner, and Martin Schnaiter
Atmos. Chem. Phys., 18, 15767–15781, https://doi.org/10.5194/acp-18-15767-2018, https://doi.org/10.5194/acp-18-15767-2018, 2018
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Using light diffraction it is possible to detect microscopic features within ice particles that have not yet been fully characterized. Here, this technique was applied in airborne measurements, where it was found that majority of atmospheric ice particles have features that significantly change the way ice particles interact with solar light. The microscopic features make ice-containing clouds more reflective than previously thought, which could have consequences for predicting our climate.
Ramakrishna Ramisetty, Ahmed Abdelmonem, Xiaoli Shen, Harald Saathoff, Thomas Leisner, and Claudia Mohr
Atmos. Meas. Tech., 11, 4345–4360, https://doi.org/10.5194/amt-11-4345-2018, https://doi.org/10.5194/amt-11-4345-2018, 2018
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In this study we coupled a laser ablation aerosol time-of-flight (LAAPTOF) single-particle mass spectrometer, originally equipped with an excimer laser, to a femtosecond laser. The objective was to assess the influence of the higher laser power density of the femtosecond laser on ablation–ionization of atmospheric particles, ion signal, and ultimately quantitative abilities of the single-particle mass spectrometer.
Xiaoli Shen, Ramakrishna Ramisetty, Claudia Mohr, Wei Huang, Thomas Leisner, and Harald Saathoff
Atmos. Meas. Tech., 11, 2325–2343, https://doi.org/10.5194/amt-11-2325-2018, https://doi.org/10.5194/amt-11-2325-2018, 2018
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This paper presents performance data and reference spectra from the commercially available single-particle mass spectrometer LAAPTOF. The main characteristics of the instrument, like its detection efficiency, are given for a wide particle size range. Furthermore, reference mass spectra for 32 well-defined different particle types relevant for atmospheric aerosol compounds are presented. It is shown that these reference mass spectra are very useful in analysis of atmospheric aerosol particles.
Mario Nachbar, Denis Duft, and Thomas Leisner
Atmos. Chem. Phys., 18, 3419–3431, https://doi.org/10.5194/acp-18-3419-2018, https://doi.org/10.5194/acp-18-3419-2018, 2018
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The crystallization process of amorphous ice below 160 K forms nano-crystalline ice. We report high-quality vapor pressure measurements over ice crystallized from amorphous ice below 160 K. We show that the vapor pressure is increased by more than 100 % compared to bulk crystalline ice and that amorphous ice always forms first, followed by the crystallization of nano-crystalline ice. Our findings are relevant for cold ice clouds in the atmospheres of planets, e.g., Earth and Mars.
Wei Huang, Harald Saathoff, Aki Pajunoja, Xiaoli Shen, Karl-Heinz Naumann, Robert Wagner, Annele Virtanen, Thomas Leisner, and Claudia Mohr
Atmos. Chem. Phys., 18, 2883–2898, https://doi.org/10.5194/acp-18-2883-2018, https://doi.org/10.5194/acp-18-2883-2018, 2018
Sylvia C. Sullivan, Corinna Hoose, Alexei Kiselev, Thomas Leisner, and Athanasios Nenes
Atmos. Chem. Phys., 18, 1593–1610, https://doi.org/10.5194/acp-18-1593-2018, https://doi.org/10.5194/acp-18-1593-2018, 2018
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Ice multiplication (IM) processes can have a profound impact on cloud and precipitation development but are poorly understood. Here we study whether a lower limit of ice nuclei exists to initiate IM. The lower limit is found to be extremely low (0.01 per liter or less). A counterintuitive but profound conclusion thus emerges: IM requires cloud formation around a thermodynamic
sweet spotand is sensitive to fluctuations in cloud condensation nuclei concentration alone.
Martin Schnaiter, Emma Järvinen, Ahmed Abdelmonem, and Thomas Leisner
Atmos. Meas. Tech., 11, 341–357, https://doi.org/10.5194/amt-11-341-2018, https://doi.org/10.5194/amt-11-341-2018, 2018
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PHIPS-HALO is a novel aircraft instrument for cloud research. It combines microscopic imaging of single cloud particles with the measurement of their spacial light scattering properties. The knowledge of how atmospheric ice particles in clouds scatter visible light is important for improving future climate models.
Claudia Linke, Inas Ibrahim, Nina Schleicher, Regina Hitzenberger, Meinrat O. Andreae, Thomas Leisner, and Martin Schnaiter
Atmos. Meas. Tech., 9, 5331–5346, https://doi.org/10.5194/amt-9-5331-2016, https://doi.org/10.5194/amt-9-5331-2016, 2016
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Various carbonaceous materials are present in the atmosphere. Besides gaseous organic compounds, carbonaceous particles like soot are emitted into the air from traffic sources, residential wood combustion, or wildfires. Variable chemical compositions of such materials, which often result from incomplete combustion processes, show differences in the absorption behavior at visible wavelengths. Our instrument is able to measure the absorption at three visible wavelengths.
Andreas Peckhaus, Alexei Kiselev, Thibault Hiron, Martin Ebert, and Thomas Leisner
Atmos. Chem. Phys., 16, 11477–11496, https://doi.org/10.5194/acp-16-11477-2016, https://doi.org/10.5194/acp-16-11477-2016, 2016
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The precipitation in midlatitude clouds proceeds predominantly via nucleation of ice in the supercooled droplets containing foreign inclusions, like feldspar mineral dust, that have been recently identified as one of the most active ice nucleating agents in the atmosphere. We have built an apparatus to observe the freezing of feldspar immersed in up to 1500 identical droplets simultaneously. With this setup we investigated four feldspar samples and show that it can induce freezing at −5 °C.
Ahmed Abdelmonem, Emma Järvinen, Denis Duft, Edwin Hirst, Steffen Vogt, Thomas Leisner, and Martin Schnaiter
Atmos. Meas. Tech., 9, 3131–3144, https://doi.org/10.5194/amt-9-3131-2016, https://doi.org/10.5194/amt-9-3131-2016, 2016
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The properties of ice crystals present in mixed-phase and ice clouds influence the radiation properties, precipitation occurrence and lifetime of these clouds. It is necessary to investigate the optical and microphysical properties of cloud particles particularly in situ, and to get correlation between these properties. To this end we have developed PHIPS-HALO to measure the optical properties and the corresponding microphysical parameters of individual cloud particles simultaneously.
Karoliina Ignatius, Thomas B. Kristensen, Emma Järvinen, Leonid Nichman, Claudia Fuchs, Hamish Gordon, Paul Herenz, Christopher R. Hoyle, Jonathan Duplissy, Sarvesh Garimella, Antonio Dias, Carla Frege, Niko Höppel, Jasmin Tröstl, Robert Wagner, Chao Yan, Antonio Amorim, Urs Baltensperger, Joachim Curtius, Neil M. Donahue, Martin W. Gallagher, Jasper Kirkby, Markku Kulmala, Ottmar Möhler, Harald Saathoff, Martin Schnaiter, Antonio Tomé, Annele Virtanen, Douglas Worsnop, and Frank Stratmann
Atmos. Chem. Phys., 16, 6495–6509, https://doi.org/10.5194/acp-16-6495-2016, https://doi.org/10.5194/acp-16-6495-2016, 2016
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Viscous solid or semi-solid secondary organic aerosol (SOA) may influence cloud properties through ice nucleation in the atmosphere. Here, we observed heterogeneous ice nucleation of viscous α-pinene SOA at temperatures between −39 °C and −37.2 °C with ice saturation ratios significantly below the homogeneous freezing limit. Global modelling suggests that viscous biogenic SOA are present in regions where cirrus formation takes place and could contribute to the global ice nuclei budget.
Emma Järvinen, Karoliina Ignatius, Leonid Nichman, Thomas B. Kristensen, Claudia Fuchs, Christopher R. Hoyle, Niko Höppel, Joel C. Corbin, Jill Craven, Jonathan Duplissy, Sebastian Ehrhart, Imad El Haddad, Carla Frege, Hamish Gordon, Tuija Jokinen, Peter Kallinger, Jasper Kirkby, Alexei Kiselev, Karl-Heinz Naumann, Tuukka Petäjä, Tamara Pinterich, Andre S. H. Prevot, Harald Saathoff, Thea Schiebel, Kamalika Sengupta, Mario Simon, Jay G. Slowik, Jasmin Tröstl, Annele Virtanen, Paul Vochezer, Steffen Vogt, Andrea C. Wagner, Robert Wagner, Christina Williamson, Paul M. Winkler, Chao Yan, Urs Baltensperger, Neil M. Donahue, Rick C. Flagan, Martin Gallagher, Armin Hansel, Markku Kulmala, Frank Stratmann, Douglas R. Worsnop, Ottmar Möhler, Thomas Leisner, and Martin Schnaiter
Atmos. Chem. Phys., 16, 4423–4438, https://doi.org/10.5194/acp-16-4423-2016, https://doi.org/10.5194/acp-16-4423-2016, 2016
Leonid Nichman, Claudia Fuchs, Emma Järvinen, Karoliina Ignatius, Niko Florian Höppel, Antonio Dias, Martin Heinritzi, Mario Simon, Jasmin Tröstl, Andrea Christine Wagner, Robert Wagner, Christina Williamson, Chao Yan, Paul James Connolly, James Robert Dorsey, Jonathan Duplissy, Sebastian Ehrhart, Carla Frege, Hamish Gordon, Christopher Robert Hoyle, Thomas Bjerring Kristensen, Gerhard Steiner, Neil McPherson Donahue, Richard Flagan, Martin William Gallagher, Jasper Kirkby, Ottmar Möhler, Harald Saathoff, Martin Schnaiter, Frank Stratmann, and António Tomé
Atmos. Chem. Phys., 16, 3651–3664, https://doi.org/10.5194/acp-16-3651-2016, https://doi.org/10.5194/acp-16-3651-2016, 2016
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Processes in the atmosphere are often governed by the physical and chemical properties of small cloud particles. Ice, water, and mixed clouds, as well as viscous aerosols, were formed under controlled conditions at the CLOUD-CERN facility. The experimental results show a link between cloud particle properties and their unique optical fingerprints. The classification map presented here allows easier discrimination between various particles such as viscous organic aerosol, salt, ice, and liquid.
Robert Wagner, Alexei Kiselev, Ottmar Möhler, Harald Saathoff, and Isabelle Steinke
Atmos. Chem. Phys., 16, 2025–2042, https://doi.org/10.5194/acp-16-2025-2016, https://doi.org/10.5194/acp-16-2025-2016, 2016
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We have investigated the enhancement of the ice nucleation ability of well-known and abundant ice nucleating particles like dust grains due to pre-activation. Temporary exposure to a low temperature (228 K) provokes that pores and surface cracks of the particles are filled with ice, which makes them better nuclei for the growth of macroscopic ice crystals at high temperatures (245–260 K).
C. R. Hoyle, C. Fuchs, E. Järvinen, H. Saathoff, A. Dias, I. El Haddad, M. Gysel, S. C. Coburn, J. Tröstl, A.-K. Bernhammer, F. Bianchi, M. Breitenlechner, J. C. Corbin, J. Craven, N. M. Donahue, J. Duplissy, S. Ehrhart, C. Frege, H. Gordon, N. Höppel, M. Heinritzi, T. B. Kristensen, U. Molteni, L. Nichman, T. Pinterich, A. S. H. Prévôt, M. Simon, J. G. Slowik, G. Steiner, A. Tomé, A. L. Vogel, R. Volkamer, A. C. Wagner, R. Wagner, A. S. Wexler, C. Williamson, P. M. Winkler, C. Yan, A. Amorim, J. Dommen, J. Curtius, M. W. Gallagher, R. C. Flagan, A. Hansel, J. Kirkby, M. Kulmala, O. Möhler, F. Stratmann, D. R. Worsnop, and U. Baltensperger
Atmos. Chem. Phys., 16, 1693–1712, https://doi.org/10.5194/acp-16-1693-2016, https://doi.org/10.5194/acp-16-1693-2016, 2016
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A significant portion of sulphate, an important constituent of atmospheric aerosols, is formed via the aqueous phase oxidation of sulphur dioxide by ozone. The rate of this reaction has previously only been measured over a relatively small temperature range. Here, we use the state of the art CLOUD chamber at CERN to perform the first measurements of this reaction rate in super-cooled droplets, confirming that the existing extrapolation of the reaction rate to sub-zero temperatures is accurate.
P. Vochezer, E. Järvinen, R. Wagner, P. Kupiszewski, T. Leisner, and M. Schnaiter
Atmos. Meas. Tech., 9, 159–177, https://doi.org/10.5194/amt-9-159-2016, https://doi.org/10.5194/amt-9-159-2016, 2016
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To study clouds constituting of liquid droplets as well as ice particles we used the latest versions of the Small Ice Detector which record high resolution scattering patterns of individual small cloud particles. In the case of a droplet its precise size is obtained and for ice particles its shape is deduced from the scattering pattern.We present results from artificial clouds at the AIDA cloud chamber and natural clouds probed at a mountain top station as well as from an aircraft in the arctic.
A. Abdelmonem, J. Lützenkirchen, and T. Leisner
Atmos. Meas. Tech., 8, 3519–3526, https://doi.org/10.5194/amt-8-3519-2015, https://doi.org/10.5194/amt-8-3519-2015, 2015
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This manuscript belongs and is important to the environmental and atmospheric science, particularly cloud formation and cloud seeding, and presents a setup to apply Second Harmonic Generation spectroscopy to heterogeneous freezing research. We describe the setup and provide first results on temperature-dependent structural changes of water on the surfaces of two relevant atmospheric aerosol substances (sapphire and mica as poor and good ice nucleators, respectively).
J. Diab, T. Streibel, F. Cavalli, S. C. Lee, H. Saathoff, A. Mamakos, J. C. Chow, L.-W. A. Chen, J. G. Watson, O. Sippula, and R. Zimmermann
Atmos. Meas. Tech., 8, 3337–3353, https://doi.org/10.5194/amt-8-3337-2015, https://doi.org/10.5194/amt-8-3337-2015, 2015
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This paper depicts several fields of application of a new analytical method, which expands the well-established EC/OC method, which enables one to measure the carbon content (organic and elemental) of particulate aerosols. It was coupled to photo-ionization mass spectrometry to get structural information of the evolving carbonaceous species. Application fields such as smoke chamber-, ambient - and wood combustion particles were addressed, covering exemplary primary and secondary aerosol sources.
J. Meyer, C. Rolf, C. Schiller, S. Rohs, N. Spelten, A. Afchine, M. Zöger, N. Sitnikov, T. D. Thornberry, A. W. Rollins, Z. Bozóki, D. Tátrai, V. Ebert, B. Kühnreich, P. Mackrodt, O. Möhler, H. Saathoff, K. H. Rosenlof, and M. Krämer
Atmos. Chem. Phys., 15, 8521–8538, https://doi.org/10.5194/acp-15-8521-2015, https://doi.org/10.5194/acp-15-8521-2015, 2015
I. Steinke, C. Hoose, O. Möhler, P. Connolly, and T. Leisner
Atmos. Chem. Phys., 15, 3703–3717, https://doi.org/10.5194/acp-15-3703-2015, https://doi.org/10.5194/acp-15-3703-2015, 2015
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Ice nucleation in clouds has a significant influence on the global radiative budget and the hydrological cycle. Several studies have investigated the ice formation in droplets and parameterizations have been developed in order to include immersion freezing in climate models. In contrast, there are fewer studies regarding the conversion of water vapor into ice (so-called deposition nucleation) which is the topic of this paper which investigates deposition nucleation by Arizona Test dust in detail
N. Hiranuma, S. Augustin-Bauditz, H. Bingemer, C. Budke, J. Curtius, A. Danielczok, K. Diehl, K. Dreischmeier, M. Ebert, F. Frank, N. Hoffmann, K. Kandler, A. Kiselev, T. Koop, T. Leisner, O. Möhler, B. Nillius, A. Peckhaus, D. Rose, S. Weinbruch, H. Wex, Y. Boose, P. J. DeMott, J. D. Hader, T. C. J. Hill, Z. A. Kanji, G. Kulkarni, E. J. T. Levin, C. S. McCluskey, M. Murakami, B. J. Murray, D. Niedermeier, M. D. Petters, D. O'Sullivan, A. Saito, G. P. Schill, T. Tajiri, M. A. Tolbert, A. Welti, T. F. Whale, T. P. Wright, and K. Yamashita
Atmos. Chem. Phys., 15, 2489–2518, https://doi.org/10.5194/acp-15-2489-2015, https://doi.org/10.5194/acp-15-2489-2015, 2015
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Seventeen ice nucleation measurement techniques contributed to investigate the immersion freezing behavior of illite NX. All data showed a similar temperature trend, but the measured ice nucleation activity was on average smaller for the wet suspended samples and higher for the dry-dispersed aerosol samples at high temperatures. A continued investigation and collaboration is necessary to obtain further insights into consistency or diversity of ice nucleation measurements.
N. Hiranuma, M. Paukert, I. Steinke, K. Zhang, G. Kulkarni, C. Hoose, M. Schnaiter, H. Saathoff, and O. Möhler
Atmos. Chem. Phys., 14, 13145–13158, https://doi.org/10.5194/acp-14-13145-2014, https://doi.org/10.5194/acp-14-13145-2014, 2014
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A new heterogeneous ice nucleation parameterization is developed and implemented in cloud models. The results of our simulations suggest stronger influence of dust particles lifted to the upper troposphere on heterogeneous nucleation and more ice nucleation at temperature and humidity conditions relevant to both mixed-phase and cirrus clouds when compared to the existing parametrical frameworks.
D. W. Fahey, R.-S. Gao, O. Möhler, H. Saathoff, C. Schiller, V. Ebert, M. Krämer, T. Peter, N. Amarouche, L. M. Avallone, R. Bauer, Z. Bozóki, L. E. Christensen, S. M. Davis, G. Durry, C. Dyroff, R. L. Herman, S. Hunsmann, S. M. Khaykin, P. Mackrodt, J. Meyer, J. B. Smith, N. Spelten, R. F. Troy, H. Vömel, S. Wagner, and F. G. Wienhold
Atmos. Meas. Tech., 7, 3177–3213, https://doi.org/10.5194/amt-7-3177-2014, https://doi.org/10.5194/amt-7-3177-2014, 2014
N. Hoffmann, A. Kiselev, D. Rzesanke, D. Duft, and T. Leisner
Atmos. Meas. Tech., 6, 2373–2382, https://doi.org/10.5194/amt-6-2373-2013, https://doi.org/10.5194/amt-6-2373-2013, 2013
H. Saathoff, S. Henin, K. Stelmaszczyk, M. Petrarca, R. Delagrange, Z. Hao, J. Lüder, O. Möhler, Y. Petit, P. Rohwetter, M. Schnaiter, J. Kasparian, T. Leisner, J.-P. Wolf, and L. Wöste
Atmos. Chem. Phys., 13, 4593–4604, https://doi.org/10.5194/acp-13-4593-2013, https://doi.org/10.5194/acp-13-4593-2013, 2013
J. Skrotzki, P. Connolly, M. Schnaiter, H. Saathoff, O. Möhler, R. Wagner, M. Niemand, V. Ebert, and T. Leisner
Atmos. Chem. Phys., 13, 4451–4466, https://doi.org/10.5194/acp-13-4451-2013, https://doi.org/10.5194/acp-13-4451-2013, 2013
M. Laborde, M. Schnaiter, C. Linke, H. Saathoff, K.-H. Naumann, O. Möhler, S. Berlenz, U. Wagner, J. W. Taylor, D. Liu, M. Flynn, J. D. Allan, H. Coe, K. Heimerl, F. Dahlkötter, B. Weinzierl, A. G. Wollny, M. Zanatta, J. Cozic, P. Laj, R. Hitzenberger, J. P. Schwarz, and M. Gysel
Atmos. Meas. Tech., 5, 3077–3097, https://doi.org/10.5194/amt-5-3077-2012, https://doi.org/10.5194/amt-5-3077-2012, 2012
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Multiple pathways for the formation of secondary organic aerosol in the North China Plain in summer
Insights into characteristics and formation mechanisms of secondary organic aerosols in the Guangzhou urban area
An attribution of the low single-scattering albedo of biomass burning aerosol over the southeastern Atlantic
Measurement report: Rapid changes of chemical characteristics and health risks for highly time resolved trace elements in PM2.5 in a typical industrial city in response to stringent clean air actions
Measurement report: Summertime fluorescence characteristics of atmospheric water-soluble organic carbon in the marine boundary layer of the western Arctic Ocean
High frequency of new particle formation events driven by summer monsoon in the central Tibetan Plateau, China
Chemical precursors of new particle formation in coastal New Zealand
Insights into the single-particle composition, size, mixing state, and aspect ratio of freshly emitted mineral dust from field measurements in the Moroccan Sahara using electron microscopy
Seasonal variation of aerosol iron solubility in coarse and fine particles at an inland city in northwestern China
Unambiguous identification of N-containing oxygenated organic molecules using a chemical-ionization Orbitrap (CI-Orbitrap) in an eastern Chinese megacity
Estimating hub-height wind speed based on a machine learning algorithm: implications for wind energy assessment
Characteristics and degradation of organic aerosols from cooking sources based on hourly observations of organic molecular markers in urban environments
Characteristics of particulate-bound n-alkanes indicating sources of PM2.5 in Beijing, China
Characterization of volatile organic compounds and submicron organic aerosol in a traffic environment
Non-volatile marine and non-refractory continental sources of particle-phase amine during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES)
Effects of transport on a biomass burning plume from Indochina during EMeRGe-Asia identified by WRF-Chem
The shifting of secondary inorganic aerosol formation mechanisms during haze aggravation: the decisive role of aerosol liquid water
Arctic observations of Hydroperoxymethyl Thioformate (HPMTF) – seasonal behavior and relationship to other oxidation products from Dimethyl Sulfide at the Zeppelin Observatory, Svalbard
Measurement report: Diurnal variations of brown carbon during two distinct seasons in a megacity in Northeast China
Collective geographical ecoregions and precursor sources driving Arctic new particle formation
Measurement report: Chemical components and 13C and 15N isotope ratios of fine aerosols over Tianjin, North China: year-round observations
High contribution of anthropogenic combustion sources to atmospheric inorganic reactive nitrogen in South China evidenced by isotopes
Impact of biogenic secondary organic aerosol (SOA) loading on the molecular composition of wintertime PM2.5 in urban Tianjin: an insight from Fourier transform ion cyclotron resonance mass spectrometry
Impacts of biomass burning and photochemical processing on the light absorption of brown carbon in the southeastern Tibetan Plateau
Fates of secondary organic aerosols in the atmosphere identified from compound-specific dual-carbon isotope analysis of oxalic acid
Vertical profiles of volatile organic compounds and fine particles in atmospheric air by using aerial drone with miniaturized samplers and portable devices
Measurement report: Aerosol vertical profiles over the western North Atlantic Ocean during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES)
Characteristics of fine particle matter at the top of Shanghai Tower
Measurement report: Abundance and fractional solubilities of aerosol metals in urban Hong Kong – insights into factors that control aerosol metal dissolution in an urban site in South China
Measurement report: Intensive biomass burning emissions and rapid nitrate formation drive severe haze formation in the Sichuan Basin, China – insights from aerosol mass spectrometry
African smoke particles act as cloud condensation nuclei in the wintertime tropical North Atlantic boundary layer over Barbados
Measurement report: Changes in light absorption and molecular composition of water-soluble humic-like substances during a winter haze bloom-decay process in Guangzhou, China
Effects of long-range transport of air pollutants on nitrogenous organic matters in mountain background region of Southeast China: Sources and influencing factors identified by observation and modal calculation
Varying chiral ratio of pinic acid enantiomers above the Amazon rainforest
Impact of aging on the sources, volatility, and viscosity of organic aerosols in Chinese outflows
A one-year ACSM source analysis of organic aerosol particle contributions from anthropogenic sources after long-range transport at the TROPOS research station Melpitz
Biogenic and anthropogenic sources of isoprene and monoterpenes and their secondary organic aerosol in Delhi, India
Amino acids, carbohydrates and lipids in the tropical oligotrophic Atlantic Ocean: Sea-to-air transfer and atmospheric in situ formation
Different physicochemical behaviors of nitrate and ammonium during transport: a case study on Mt. Hua, China
A method for using stationary networks to observe long-term trends of on-road emission factors of primary aerosol from heavy-duty vehicles
Atmospheric particle abundance and sea salt aerosol observations in the springtime Arctic: a focus on blowing snow and leads
Measurement report: Contrasting elevation-dependent light absorption by black and brown carbon: lessons from in situ measurements from the highly polluted Sichuan Basin to the pristine Tibetan Plateau
Long-term declines in atmospheric nitrogen and sulfur deposition reduce critical loads exceedances at multiple Canadian rural sites, 2000–2018
Composition and mixing state of Arctic aerosol and cloud residual particles from long-term single-particle observations at Zeppelin Observatory, Svalbard
A meteorological overview of the ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) campaign over the southeastern Atlantic during 2016–2018: Part 2 – Daily and synoptic characteristics
Long-range transported pollution from the Middle East and its impact on carbonaceous aerosol sources over Cyprus
Measurement report: Characterization of sugars and amino acids in atmospheric fine particulates and their relationship to local primary sources
Organic enrichment in droplet residual particles relative to out of cloud over the northwestern Atlantic: analysis of airborne ACTIVATE data
Long-term trends and drivers of aerosol pH in eastern China
Potential underestimation of ambient brown carbon absorption based on the methanol extraction method and its impacts on source analysis
Yifang Gu, Ru-Jin Huang, Jing Duan, Wei Xu, Chunshui Lin, Haobin Zhong, Ying Wang, Haiyan Ni, Quan Liu, Ruiguang Xu, Litao Wang, and Yong Jie Li
Atmos. Chem. Phys., 23, 5419–5433, https://doi.org/10.5194/acp-23-5419-2023, https://doi.org/10.5194/acp-23-5419-2023, 2023
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Secondary organic aerosol (SOA) can be produced by various pathways, but its formation mechanisms are unclear. Observations were conducted in the North China Plain during a highly oxidizing atmosphere in summer. We found that fast photochemistry dominated SOA formation during daytime. Two types of aqueous-phase chemistry (nocturnal and daytime processing) take place at high relative humidity. The potential transformation from primary organic aerosol (POA) to SOA was also an important pathway.
Miaomiao Zhai, Ye Kuang, Li Liu, Yao He, Biao Luo, Wanyun Xu, Jiangchuan Tao, Yu Zou, Fei Li, Changqin Yin, Chunhui Li, Hanbing Xu, and Xuejiao Deng
Atmos. Chem. Phys., 23, 5119–5133, https://doi.org/10.5194/acp-23-5119-2023, https://doi.org/10.5194/acp-23-5119-2023, 2023
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Using year-long aerosol mass spectrometer measurements, roles of secondary organic aerosols (SOA) during haze formations in an urban area of southern China were systematically analyzed. Almost all severe haze events were accompanied by continuous daytime and nighttime SOA formations, whereas coordinated gas-phase photochemistry and aqueous-phase reactions likely played significant roles in quick daytime SOA formations, and nitrate radicals played significant roles in nighttime SOA formations.
Amie Dobracki, Paquita Zuidema, Steven G. Howell, Pablo Saide, Steffen Freitag, Allison C. Aiken, Sharon P. Burton, Arthur J. Sedlacek III, Jens Redemann, and Robert Wood
Atmos. Chem. Phys., 23, 4775–4799, https://doi.org/10.5194/acp-23-4775-2023, https://doi.org/10.5194/acp-23-4775-2023, 2023
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Southern Africa produces approximately one-third of the world’s carbon from fires. The thick smoke layer can flow westward, interacting with the southeastern Atlantic cloud deck. The net radiative impact can alter regional circulation patterns, impacting rainfall over Africa. We find that the smoke is highly absorbing of sunlight, mostly because it contains more black carbon than smoke over the Northern Hemisphere.
Rui Li, Yining Gao, Yubao Chen, Meng Peng, Weidong Zhao, Gehui Wang, and Jiming Hao
Atmos. Chem. Phys., 23, 4709–4726, https://doi.org/10.5194/acp-23-4709-2023, https://doi.org/10.5194/acp-23-4709-2023, 2023
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A random forest model was used to isolate the effects of emission and meteorology to trace elements in PM2.5 in Tangshan. The results suggested that control measures facilitated decreases of Ga, Co, Pb, Zn, and As, due to the strict implementation of coal-to-gas strategies and optimisation of industrial structure and layout. However, the deweathered levels of Ca, Cr, and Fe only displayed minor decreases, indicating that ferrous metal smelting and vehicle emission controls should be enhanced.
Jinyoung Jung, Yuzo Miyazaki, Jin Hur, Yun Kyung Lee, Mi Hae Jeon, Youngju Lee, Kyoung-Ho Cho, Hyun Young Chung, Kitae Kim, Jung-Ok Choi, Catherine Lalande, Joo-Hong Kim, Taejin Choi, Young Jun Yoon, Eun Jin Yang, and Sung-Ho Kang
Atmos. Chem. Phys., 23, 4663–4684, https://doi.org/10.5194/acp-23-4663-2023, https://doi.org/10.5194/acp-23-4663-2023, 2023
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This study examined the summertime fluorescence properties of water-soluble organic carbon (WSOC) in aerosols over the western Arctic Ocean. We found that the WSOC in fine-mode aerosols in coastal areas showed a higher polycondensation degree and aromaticity than in sea-ice-covered areas. The fluorescence properties of atmospheric WSOC in the summertime marine Arctic boundary can improve our understanding of the WSOC chemical and biological linkages at the ocean–sea-ice–atmosphere interface.
Lizi Tang, Min Hu, Dongjie Shang, Xin Fang, Jianjiong Mao, Wanyun Xu, Jiacheng Zhou, Weixiong Zhao, Yaru Wang, Chong Zhang, Yingjie Zhang, Jianlin Hu, Limin Zeng, Chunxiang Ye, Song Guo, and Zhijun Wu
Atmos. Chem. Phys., 23, 4343–4359, https://doi.org/10.5194/acp-23-4343-2023, https://doi.org/10.5194/acp-23-4343-2023, 2023
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There was an evident distinction in the frequency of new particle formation (NPF) events at Nam Co station on the Tibetan Plateau: 15 % in pre-monsoon season and 80 % in monsoon season. The frequent NPF events in monsoon season resulted from the higher frequency of southerly air masses, which brought the organic precursors to participate in the NPF process. It increased the amount of aerosol and CCN compared with those in pre-monsoon season, which may markedly affect earth's radiation balance.
Maija Peltola, Clémence Rose, Jonathan V. Trueblood, Sally Gray, Mike Harvey, and Karine Sellegri
Atmos. Chem. Phys., 23, 3955–3983, https://doi.org/10.5194/acp-23-3955-2023, https://doi.org/10.5194/acp-23-3955-2023, 2023
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We measured the chemical composition of ambient ions at a coastal New Zealand site and connected these data with aerosol size distribution data to study the chemical precursors of new particle formation at the site. Our results showed that iodine oxides and sulfur species were important for particle formation in marine air, while in land-influenced air sulfuric acid and organics were connected to new particle formation events.
Agnesh Panta, Konrad Kandler, Andres Alastuey, Cristina González-Flórez, Adolfo González-Romero, Martina Klose, Xavier Querol, Cristina Reche, Jesús Yus-Díez, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 23, 3861–3885, https://doi.org/10.5194/acp-23-3861-2023, https://doi.org/10.5194/acp-23-3861-2023, 2023
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Desert dust is a major aerosol component of the Earth system and affects the climate. Dust properties are influenced by particle size, mineralogy, shape, and mixing state. This work characterizes freshly emitted individual mineral dust particles from a major source region using electron microscopy. Our new insights into critical particle-specific information will contribute to better constraining climate models that consider mineralogical variations in their representation of the dust cycle.
Huanhuan Zhang, Rui Li, Chengpeng Huang, Xiaofei Li, Shuwei Dong, Fu Wang, Tingting Li, Yizhu Chen, Guohua Zhang, Yan Ren, Qingcai Chen, Ru-jin Huang, Siyu Chen, Tao Xue, Xinming Wang, and Mingjin Tang
Atmos. Chem. Phys., 23, 3543–3559, https://doi.org/10.5194/acp-23-3543-2023, https://doi.org/10.5194/acp-23-3543-2023, 2023
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This work investigated the seasonal variation of aerosol Fe solubility for coarse and fine particles in Xi’an, a megacity in northwestern China severely affected by anthropogenic emission and desert dust aerosol. In addition, we discussed in depth what controlled aerosol Fe solubility at different seasons for coarse and fine particles.
Yiqun Lu, Yingge Ma, Dan Dan Huang, Shengrong Lou, Sheng'ao Jing, Yaqin Gao, Hongli Wang, Yanjun Zhang, Hui Chen, Yunhua Chang, Naiqiang Yan, Jianmin Chen, Christian George, Matthieu Riva, and Cheng Huang
Atmos. Chem. Phys., 23, 3233–3245, https://doi.org/10.5194/acp-23-3233-2023, https://doi.org/10.5194/acp-23-3233-2023, 2023
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N-containing oxygenated organic molecules have been identified as important precursors of aerosol particles. We used an ultra-high-resolution mass spectrometer coupled with an online sample inlet to accurately measure their molecular composition, concentration level and variation patterns. We show their formation process and influencing factors in a Chinese megacity involving various volatile organic compound precursors and atmospheric oxidants, and we highlight the influence of PM2.5 episodes.
Boming Liu, Xin Ma, Jianping Guo, Hui Li, Shikuan Jin, Yingying Ma, and Wei Gong
Atmos. Chem. Phys., 23, 3181–3193, https://doi.org/10.5194/acp-23-3181-2023, https://doi.org/10.5194/acp-23-3181-2023, 2023
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Wind energy is one of the most essential clean and renewable forms of energy in today’s world. However, the traditional power law method generally estimates the hub-height wind speed by assuming a constant exponent between surface and hub-height wind speeds. This inevitably leads to significant uncertainties in estimating the wind speed profile. To minimize the uncertainties, we here use a machine learning algorithm known as random forest to estimate the wind speed at hub height.
Rui Li, Kun Zhang, Qing Li, Liumei Yang, Shunyao Wang, Zhiqiang Liu, Xiaojuan Zhang, Hui Chen, Yanan Yi, Jialiang Feng, Qiongqiong Wang, Ling Huang, Wu Wang, Yangjun Wang, Jian Zhen Yu, and Li Li
Atmos. Chem. Phys., 23, 3065–3081, https://doi.org/10.5194/acp-23-3065-2023, https://doi.org/10.5194/acp-23-3065-2023, 2023
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Molecular markers in organic aerosol (OA) provide specific source information on PM2.5, and the contribution of cooking emissions to OA is significant, especially in urban environments. This study investigates the variation in concentrations and oxidative degradation of fatty acids and corresponding oxidation products in ambient air, which can be a guide for the refinement of aerosol source apportionment and provide scientific support for the development of emission source control policies.
Jiyuan Yang, Guoyang Lei, Chang Liu, Yutong Wu, Kai Hu, Jinfeng Zhu, Junsong Bao, Weili Lin, and Jun Jin
Atmos. Chem. Phys., 23, 3015–3029, https://doi.org/10.5194/acp-23-3015-2023, https://doi.org/10.5194/acp-23-3015-2023, 2023
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The characteristics of n-alkanes and the contributions of various sources of PM2.5 in the atmosphere in Beijing were studied. There were marked seasonal and diurnal differences in the n-alkane concentrations (p<0.01). Particulate-bound n-alkanes were supplied by anthropogenic and biogenic sources; fossil fuel combustion was the dominant contributor. Vehicle exhausts strongly affect PM2.5 pollution. Controlling vehicle exhaust emissions is key to control n-alkane and PM2.5 pollution in Beijing.
Sanna Saarikoski, Heidi Hellén, Arnaud P. Praplan, Simon Schallhart, Petri Clusius, Jarkko V. Niemi, Anu Kousa, Toni Tykkä, Rostislav Kouznetsov, Minna Aurela, Laura Salo, Topi Rönkkö, Luis M. F. Barreira, Liisa Pirjola, and Hilkka Timonen
Atmos. Chem. Phys., 23, 2963–2982, https://doi.org/10.5194/acp-23-2963-2023, https://doi.org/10.5194/acp-23-2963-2023, 2023
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This study elucidates properties and sources of volatile organic compounds (VOCs) and organic aerosol (OA) in a traffic environment. Anthropogenic VOCs (aVOCs) were clearly higher than biogenic VOCs (bVOCs), but bVOCs produced a larger portion of oxidation products. OA consisted mostly of oxygenated OA, representing secondary OA (SOA). SOA was partly associated with bVOCs, but it was also related to long-range transport. Primary OA originated mostly from traffic.
Veronica Z. Berta, Lynn M. Russell, Derek J. Price, Chia-Li Chen, Alex K. Y. Lee, Patricia K. Quinn, Timothy S. Bates, Thomas G. Bell, and Michael J. Behrenfeld
Atmos. Chem. Phys., 23, 2765–2787, https://doi.org/10.5194/acp-23-2765-2023, https://doi.org/10.5194/acp-23-2765-2023, 2023
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Amines are compounds emitted from a variety of marine and continental sources and were measured by aerosol mass spectrometry and Fourier transform infrared spectroscopy during the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) cruises. Secondary continental and primary marine sources of amines were identified by comparisons to tracers. The results show that the two methods are complementary for investigating amines in the marine environment.
Chuan-Yao Lin, Wan-Chin Chen, Yi-Yun Chien, Charles C. K. Chou, Chian-Yi Liu, Helmut Ziereis, Hans Schlager, Eric Förster, Florian Obersteiner, Ovid O. Krüger, Bruna A. Holanda, Mira L. Pöhlker, Katharina Kaiser, Johannes Schneider, Birger Bohn, Klaus Pfeilsticker, Benjamin Weyland, Maria Dolores Andrés Hernández, and John P. Burrows
Atmos. Chem. Phys., 23, 2627–2647, https://doi.org/10.5194/acp-23-2627-2023, https://doi.org/10.5194/acp-23-2627-2023, 2023
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During the EMeRGe campaign in Asia, atmospheric pollutants were measured on board the HALO aircraft. The WRF-Chem model was employed to evaluate the biomass burning (BB) plume transported from Indochina and its impact on the downstream areas. The combination of BB aerosol enhancement with cloud water resulted in a reduction in incoming shortwave radiation at the surface in southern China and the East China Sea, which potentially has significant regional climate implications.
Fei Xie, Yue Su, Yongli Tian, Yanju Shi, Xingjun Zhou, Peng Wang, Ruihong Yu, Wei Wang, Jiang He, Jinyuan Xin, and Changwei Lü
Atmos. Chem. Phys., 23, 2365–2378, https://doi.org/10.5194/acp-23-2365-2023, https://doi.org/10.5194/acp-23-2365-2023, 2023
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This work finds the shifting of secondary inorganic aerosol formation mechanisms during haze aggravation and explains the decisive role of aerosol liquid water on a broader scale (~ 500 μg m3) in an ammonia-rich atmosphere based on the in situ high-resolution online monitoring datasets.
Karolina Siegel, Yvette Gramlich, Sophie L. Haslett, Gabriel Freitas, Radovan Krejci, Paul Zieger, and Claudia Mohr
EGUsphere, https://doi.org/10.5194/egusphere-2023-146, https://doi.org/10.5194/egusphere-2023-146, 2023
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Hydroperoxymethyl thioformate (HPMTF) is a recently discovered oxidation product of dimethyl sulfide (DMS). We present a full year of concurrent gas and particle phase observations of HPMTF and other DMS oxidation products from the Arctic. We did not observe significant amounts of HPMTF in the particle phase, but a good agreement between gas phase HMPTF and methanesulfonic acid in the summer. Our study provides information about the relationship between HPMTF and other DMS oxidation products.
Yuan Cheng, Xu-bing Cao, Jiu-meng Liu, Ying-jie Zhong, Qin-qin Yu, Qiang Zhang, and Ke-bin He
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2023-51, https://doi.org/10.5194/acp-2023-51, 2023
Revised manuscript accepted for ACP
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BrC aerosols were explored in the northernmost megacity in China during a frigid winter and an agricultural-fire-impacted spring. BrC were more light-absorbing at night for both seasons, with more pronounced diurnal variations in spring, and the dominant drivers were identified as regulations on heavy-duty diesel trucks and open burning. Agricultural fires resulted in unique absorption spectra of BrC, which were characterized by distinct peak at ~365 nm.
James Brean, David C. S. Beddows, Roy M. Harrison, Congbo Song, Peter Tunved, Johan Ström, Radovan Krejci, Eyal Freud, Andreas Massling, Henrik Skov, Eija Asmi, Angelo Lupi, and Manuel Dall'Osto
Atmos. Chem. Phys., 23, 2183–2198, https://doi.org/10.5194/acp-23-2183-2023, https://doi.org/10.5194/acp-23-2183-2023, 2023
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Our results emphasize how understanding the geographical variation in surface types across the Arctic is key to understanding secondary aerosol sources. We provide a harmonised analysis of new particle formation across the Arctic.
Zhichao Dong, Chandra Mouli Pavuluri, Zhanjie Xu, Yu Wang, Peisen Li, Pingqing Fu, and Cong-Qiang Liu
Atmos. Chem. Phys., 23, 2119–2143, https://doi.org/10.5194/acp-23-2119-2023, https://doi.org/10.5194/acp-23-2119-2023, 2023
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This study has provided comprehensive baseline data of carbonaceous and inorganic aerosols as well as their isotope ratios in the Tianjin region, North China, found that Tianjin aerosols were derived from coal combustion, biomass burning and photochemical reactions of VOCs, and also implied that the Tianjin aerosols were more aged during long-range atmospheric transport in summer via carbonaceous and isotope data analysis.
Tingting Li, Jun Li, Zeyu Sun, Hongxing Jiang, Chongguo Tian, and Gan Zhang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2023-49, https://doi.org/10.5194/acp-2023-49, 2023
Revised manuscript accepted for ACP
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N-NH4+ and N-NO3- were vital components in nitrogenous aerosols and contributed 69 % to total nitrogen in PM2.5. Coal combustion was still the most important source of urban atmospheric NO3-. However, the non-agriculture sources play an increasingly important role in NH4+ emission.
Shujun Zhong, Shuang Chen, Junjun Deng, Yanbing Fan, Qiang Zhang, Qiaorong Xie, Yulin Qi, Wei Hu, Libin Wu, Xiaodong Li, Chandra Mouli Pavuluri, Jialei Zhu, Xin Wang, Di Liu, Xiaole Pan, Yele Sun, Zifa Wang, Yisheng Xu, Haijie Tong, Hang Su, Yafang Cheng, Kimitaka Kawamura, and Pingqing Fu
Atmos. Chem. Phys., 23, 2061–2077, https://doi.org/10.5194/acp-23-2061-2023, https://doi.org/10.5194/acp-23-2061-2023, 2023
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This study investigated the role of the secondary organic aerosol (SOA) loading on the molecular composition of wintertime urban aerosols by ultrahigh-resolution mass spectrometry. Results demonstrate that the SOA loading is an important factor associated with the oxidation degree, nitrate group content, and chemodiversity of nitrooxy–organosulfates. Our study also found that the hydrolysis of nitrooxy–organosulfates is a possible pathway for the formation of organosulfates.
Jie Tian, Qiyuan Wang, Yongyong Ma, Jin Wang, Yongming Han, and Junji Cao
Atmos. Chem. Phys., 23, 1879–1892, https://doi.org/10.5194/acp-23-1879-2023, https://doi.org/10.5194/acp-23-1879-2023, 2023
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We investigated the light absorption properties of brown carbon (BrC) in the Tibetan Plateau (TP). BrC made a substantial contribution to the submicron aerosol absorption, which is related to the cross-border transport of biomass burning emission and secondary aerosol from Southeast Asia. The radiative effect of BrC was half that of black carbon, which can remarkably affect the radiative balance of the TP.
Buqing Xu, Jiao Tang, Tiangang Tang, Shizhen Zhao, Guangcai Zhong, Sanyuan Zhu, Jun Li, and Gan Zhang
Atmos. Chem. Phys., 23, 1565–1578, https://doi.org/10.5194/acp-23-1565-2023, https://doi.org/10.5194/acp-23-1565-2023, 2023
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We analyzed compound-specific dual-carbon isotope signatures (Δ14C and δ13C) of dominant secondary organic aerosol (SOA) tracer molecules (i.e., oxalic acid) to investigate the fates of SOAs in the atmosphere at five emission hotspots in China. The results indicated that SOA carbon sources and chemical processes producing SOAs vary spatially and seasonally, and these variations need to be included in Chinese climate projection models and air quality management practices.
Eka Dian Pusfitasari, Jose Ruiz-Jimenez, Aleksi Tiusanen, Markus Suuronen, Jesse Haataja, Juha Kangasluoma, Krista Luoma, Tuukka Petäjä, Matti Jussila, Kari Hartonen, and Marja-Liisa Riekkola
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2023-40, https://doi.org/10.5194/acp-2023-40, 2023
Revised manuscript accepted for ACP
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A miniaturized air sampling-drone system was successfully applied for the collection of volatile organic compounds (VOCs) and for the measurement of black carbon (BC) and total particle number concentrations in atmospheric air. Here we report, for the first time, the vertical profiles of BC and aerosol number concentrations above the boreal forest in Hyytiälä (Finland) at high altitudes close to the boundary layer in autumn 2021. VOC composition with its distribution was studied as well.
Francesca Gallo, Kevin J. Sanchez, Bruce E. Anderson, Ryan Bennett, Matthew D. Brown, Ewan C. Crosbie, Chris Hostetler, Carolyn Jordan, Melissa Yang Martin, Claire E. Robinson, Lynn M. Russell, Taylor J. Shingler, Michael A. Shook, Kenneth L. Thornhill, Elizabeth B. Wiggins, Edward L. Winstead, Armin Wisthaler, Luke D. Ziemba, and Richard H. Moore
Atmos. Chem. Phys., 23, 1465–1490, https://doi.org/10.5194/acp-23-1465-2023, https://doi.org/10.5194/acp-23-1465-2023, 2023
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We integrate in situ ship- and aircraft-based measurements of aerosol, trace gases, and meteorological parameters collected during the NASA North Atlantic Aerosols and Marine Ecosystems Study (NAAMES) field campaigns in the western North Atlantic Ocean region. A comprehensive characterization of the vertical profiles of aerosol properties under different seasonal regimes is provided for improving the understanding of aerosol key processes and aerosol–cloud interactions in marine regions.
Changqin Yin, Jianming Xu, Wei Gao, Liang Pan, Yixuan Gu, Qingyan Fu, and Fan Yang
Atmos. Chem. Phys., 23, 1329–1343, https://doi.org/10.5194/acp-23-1329-2023, https://doi.org/10.5194/acp-23-1329-2023, 2023
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The particle matter (PM2.5) at the top of the 632 m high Shanghai Tower was found to be higher than the surface from June to October due to unexpected larger PM2.5 levels during early to middle afternoon at Shanghai Tower. We suppose the significant chemical production of secondary species existed in the mid-upper planetary boundary layer. We found a high nitrate concentration at the tower site for both daytime and nighttime in winter, implying efficient gas-phase and heterogeneous formation.
Junwei Yang, Lan Ma, Xiao He, Wing Chi Au, Yanhao Miao, Wen-Xiong Wang, and Theodora Nah
Atmos. Chem. Phys., 23, 1403–1419, https://doi.org/10.5194/acp-23-1403-2023, https://doi.org/10.5194/acp-23-1403-2023, 2023
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Water-soluble metals play key roles in human health and atmospheric processes. We report the seasonal abundance and fractional solubilities of different metals in aerosols collected in urban Hong Kong as well as the key factors that modulated solubilities of the various metals in fine aerosols. Our results highlight the dual roles (i.e., acidifying the aerosol particle and providing a liquid reaction medium) that sulfate plays in the acid dissolution of metals in fine aerosols in Hong Kong.
Zhier Bao, Xinyi Zhang, Qing Li, Jiawei Zhou, Guangming Shi, Li Zhou, Fumo Yang, Shaodong Xie, Dan Zhang, Chongzhi Zhai, Zhenliang Li, Chao Peng, and Yang Chen
Atmos. Chem. Phys., 23, 1147–1167, https://doi.org/10.5194/acp-23-1147-2023, https://doi.org/10.5194/acp-23-1147-2023, 2023
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We characterised non-refractory fine particulate matter (PM2.5) during winter in the Sichuan Basin (SCB), Southwest China. The factors driving severe aerosol pollution were revealed, highlighting the importance of rapid nitrate formation and intensive biomass burning. Nitrate was primarily formed through gas-phase oxidation during daytime and aqueous-phase oxidation during nighttime. Controlling nitrate and biomass burning will benefit the mitigation of haze formation in the SCB.
Haley M. Royer, Mira L. Pöhlker, Ovid Krüger, Edmund Blades, Peter Sealy, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Andrew P. Ault, Patricia K. Quinn, Paquita Zuidema, Christopher Pöhlker, Ulrich Pöschl, Meinrat Andreae, and Cassandra J. Gaston
Atmos. Chem. Phys., 23, 981–998, https://doi.org/10.5194/acp-23-981-2023, https://doi.org/10.5194/acp-23-981-2023, 2023
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This paper presents atmospheric particle chemical composition and measurements of aerosol water uptake properties collected at Ragged Point, Barbados, during the winter of 2020. The result of this study indicates the importance of small African smoke particles for cloud droplet formation in the tropical North Atlantic and highlights the large spatial and temporal pervasiveness of smoke over the Atlantic Ocean.
Chunlin Zou, Tao Cao, Meiju Li, Jianzhong Song, Bin Jiang, Wanglu Jia, Jun Li, Xiang Ding, Zhiqiang Yu, Gan Zhang, and Ping'an Peng
Atmos. Chem. Phys., 23, 963–979, https://doi.org/10.5194/acp-23-963-2023, https://doi.org/10.5194/acp-23-963-2023, 2023
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In this study, PM2.5 samples were obtained during a winter haze event in Guangzhou, China, and light absorption and molecular composition of humic-like substances (HULIS) were investigated by UV–Vis spectrophotometry and ultrahigh-resolution mass spectrometry. The findings obtained present some differences from the results reported in other regions of China and significantly enhanced our understanding of HULIS evolution during haze bloom-decay processes in the subtropic region of southern China.
Yanqin Ren, Gehui Wang, Jie Wei, Jun Tao, Zhisheng Zhang, and Hong Li
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-757, https://doi.org/10.5194/acp-2022-757, 2023
Preprint under review for ACP
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Nine quantified Nitrated aromatic compounds (NACs) in PM2.5 were examined at the peak of Mt. Wuyi. They manifested a significant rise in overall abundance in the winter and autumn. The transport of contaminants had a significant impact on NACs. Under low-NOx conditions, the formation of NACs was comparatively sensitive to NO2, suggesting that NACs would become significant in the aerosol characteristics when nitrate concentrations decreased as a result of emission reduction measures.
Denis Leppla, Nora Zannoni, Leslie Kremper, Jonathan Williams, Christopher Pöhlker, Marta Sá, Maria Christina Solci, and Thorsten Hoffmann
Atmos. Chem. Phys., 23, 809–820, https://doi.org/10.5194/acp-23-809-2023, https://doi.org/10.5194/acp-23-809-2023, 2023
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Chiral chemodiversity plays a critical role in biochemical processes such as insect and plant communication. Here we report on the measurement of chiral-specified secondary organic aerosol in the Amazon rainforest. The results show that the chiral ratio is mainly determined by large-scale emission processes. Characteristic emissions of chiral aerosol precursors from different forest ecosystems can thus provide large-scale information on different biogenic sources via chiral particle analysis.
Tingting Feng, Yingkun Wang, Weiwei Hu, Ming Zhu, Wei Song, Wei Chen, Yanyan Sang, Zheng Fang, Wei Deng, Hua Fang, Xu Yu, Cheng Wu, Bin Yuan, Shan Huang, Min Shao, Xiaofeng Huang, Lingyan He, Young Ro Lee, Lewis Gregory Huey, Francesco Canonaco, Andre S. H. Prevot, and Xinming Wang
Atmos. Chem. Phys., 23, 611–636, https://doi.org/10.5194/acp-23-611-2023, https://doi.org/10.5194/acp-23-611-2023, 2023
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To investigate the impact of aging processes on organic aerosols (OA), we conducted a comprehensive field study at a continental remote site using an on-line mass spectrometer. The results show that OA in the Chinese outflows were strongly influenced by upwind anthropogenic emissions. The aging processes can significantly decrease the OA volatility and result in a varied viscosity of OA under different circumstances, signifying the complex physiochemical properties of OA in aged plumes.
Samira Atabakhsh, Laurent Poulain, Gang Chen, Francesco Canonaco, André S. H. Prévôt, Mira Pöhlker, Alfred Wiedensohler, and Hartmut Herrmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-842, https://doi.org/10.5194/acp-2022-842, 2023
Revised manuscript accepted for ACP
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The study focuses on the aerosol chemical variations found in the rural-background station of Melpitz based on ACSM and MAAP measurements. Source apportionment on both organic aerosol (OA) and black carbon (eBC) was performed, and source seasonality was also linked to air mass trajectories. In overall, three anthropogenic sources were identified in OA and eBC, plus two additional aged-OA. Our results demonstrate the influence of transported coal-combustion-related OA even during summertime.
Daniel J. Bryant, Beth S. Nelson, Stefan J. Swift, Sri Hapsari Budisulistiorini, Will S. Drysdale, Adam R. Vaughan, Mike J. Newland, James R. Hopkins, James M. Cash, Ben Langford, Eiko Nemitz, W. Joe F. Acton, C. Nicholas Hewitt, Tuhin Mandal, Bhola R. Gurjar, Shivani, Ranu Gadi, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 23, 61–83, https://doi.org/10.5194/acp-23-61-2023, https://doi.org/10.5194/acp-23-61-2023, 2023
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This paper investigates the sources of isoprene and monoterpene compounds and their particulate-phase oxidation products in Delhi, India. This was done to improve our understanding of the sources, concentrations, and fate of volatile emissions in megacities. By studying the chemical composition of offline filter samples, we report that a significant share of the oxidised organic aerosol in Delhi is from isoprene and monoterpenes. This has implications for human health and policy development.
Manuela van Pinxteren, Sebastian Zeppenfeld, Khanneh Wadinga Fomba, Nadja Triesch, Sanja Frka, and Hartmut Herrmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-832, https://doi.org/10.5194/acp-2022-832, 2022
Revised manuscript accepted for ACP
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Important marine organic carbon compounds were identified in the Atlantic Ocean and marine aerosol particles. These compounds were strongly enriched in the atmosphere. Their enrichment was, however, not solely explained with sea-to-air transfer but also via atmospheric in situ formation. The identified compounds constituted about 50 % of the organic carbon on the aerosol particles and a pronounced coupling between ocean and atmosphere for this oligotrophic region could be concluded.
Can Wu, Cong Cao, Jianjun Li, Shaojun Lv, Jin Li, Xiaodi Liu, Si Zhang, Shijie Liu, Fan Zhang, Jingjing Meng, and Gehui Wang
Atmos. Chem. Phys., 22, 15621–15635, https://doi.org/10.5194/acp-22-15621-2022, https://doi.org/10.5194/acp-22-15621-2022, 2022
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Over the past decade, the relative abundance of NH4NO3 in aerosol has been enhanced in most urban areas of China, which profoundly affects the PM2.5 pollution episodes. Our work finds that fine-particle nitrate and ammonium exhibited distinct, different physicochemical behaviors in the aerosol aging process.
Helen L. Fitzmaurice and Ronald C. Cohen
Atmos. Chem. Phys., 22, 15403–15411, https://doi.org/10.5194/acp-22-15403-2022, https://doi.org/10.5194/acp-22-15403-2022, 2022
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We develop a novel method for finding heavy-duty vehicle (HDV) emission factors (g PM kg fuel) using regulatory sensor networks and publicly available traffic data. We find that particulate matter emission factors have decreased by a factor of ~ 9 in the past decade in the San Francisco Bay area. Because of the wide availability of similar data sets across the USA and globally, this method could be applied to other settings to understand long-term trends and regional differences in HDV emissions.
Qianjie Chen, Jessica A. Mirrielees, Sham Thanekar, Nicole A. Loeb, Rachel M. Kirpes, Lucia M. Upchurch, Anna J. Barget, Nurun Nahar Lata, Angela R. W. Raso, Stephen M. McNamara, Swarup China, Patricia K. Quinn, Andrew P. Ault, Aaron Kennedy, Paul B. Shepson, Jose D. Fuentes, and Kerri A. Pratt
Atmos. Chem. Phys., 22, 15263–15285, https://doi.org/10.5194/acp-22-15263-2022, https://doi.org/10.5194/acp-22-15263-2022, 2022
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During a spring field campaign in the coastal Arctic, ultrafine particles were enhanced during high wind speeds, and coarse-mode particles were reduced during blowing snow. Calculated periods blowing snow were overpredicted compared to observations. Sea spray aerosols produced by sea ice leads affected the composition of aerosols and snowpack. An improved understanding of aerosol emissions from leads and blowing snow is critical for predicting the future climate of the rapidly warming Arctic.
Suping Zhao, Shaofeng Qi, Ye Yu, Shichang Kang, Longxiang Dong, Jinbei Chen, and Daiying Yin
Atmos. Chem. Phys., 22, 14693–14708, https://doi.org/10.5194/acp-22-14693-2022, https://doi.org/10.5194/acp-22-14693-2022, 2022
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Light absorption by aerosols is poorly understood at the eastern slope of the Tibetan Plateau (TP). We conducted the first in situ PM1 chemical measurements from the polluted Sichuan Basin to the eastern TP. A contrasting changes in mass absorption efficiency of black and brown carbon with altitude is found due to source differences. This study contributes to the understanding of the difference in light absorption by carbon with altitude, from the polluted basins to the pristine TP.
Irene Cheng, Leiming Zhang, Zhuanshi He, Hazel Cathcart, Daniel Houle, Amanda Cole, Jian Feng, Jason O'Brien, Anne Marie Macdonald, Julian Aherne, and Jeffrey Brook
Atmos. Chem. Phys., 22, 14631–14656, https://doi.org/10.5194/acp-22-14631-2022, https://doi.org/10.5194/acp-22-14631-2022, 2022
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Nitrogen (N) and sulfur (S) deposition decreased significantly at 14 Canadian sites during 2000–2018. The greatest decline was observed in southeastern Canada owing to regional SO2 and NOx reductions. Wet deposition was more important than dry deposition, comprising 71–95 % of total N and 45–89 % of total S deposition. While critical loads (CLs) were exceeded at a few sites in the early 2000s, acidic deposition declined below CLs after 2012, which signifies recovery from legacy acidification.
Kouji Adachi, Yutaka Tobo, Makoto Koike, Gabriel Freitas, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 22, 14421–14439, https://doi.org/10.5194/acp-22-14421-2022, https://doi.org/10.5194/acp-22-14421-2022, 2022
Short summary
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Ambient aerosol and cloud residual particles in the fine mode were collected at Zeppelin Observatory in Svalbard and were analyzed using transmission electron microscopy. Fractions of mineral dust and sea salt particles increased in cloud residual samples collected at ambient temperatures below 0 °C. This study highlights the variety of aerosol and cloud residual particle compositions and mixing states that influence or are influenced by aerosol–cloud interactions in Arctic low-level clouds.
Ju-Mee Ryoo, Leonhard Pfister, Rei Ueyama, Paquita Zuidema, Robert Wood, Ian Chang, and Jens Redemann
Atmos. Chem. Phys., 22, 14209–14241, https://doi.org/10.5194/acp-22-14209-2022, https://doi.org/10.5194/acp-22-14209-2022, 2022
Short summary
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The variability in the meteorological fields during each deployment is highly modulated at a daily to synoptic timescale. This paper, along with part 1, the climatological overview paper, provides a meteorological context for interpreting the airborne measurements gathered during the three ORACLES deployments. This study supports related studies focusing on the detailed investigation of the processes controlling stratocumulus decks, aerosol lifting, transport, and their interactions.
Aliki Christodoulou, Iasonas Stavroulas, Mihalis Vrekoussis, Maximillien Desservettaz, Michael Pikridas, Elie Bimenyimana, Matic Ivančič, Martin Rigler, Philippe Goloub, Konstantina Oikonomou, Roland Sarda-Estève, Chrysanthos Savvides, Charbel Afif, Nikos Mihalopoulos, Stéphane Sauvage, and Jean Sciare
EGUsphere, https://doi.org/10.5194/egusphere-2022-1081, https://doi.org/10.5194/egusphere-2022-1081, 2022
Short summary
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Our study presents, for the first time, a detailed source identification of aerosols at an urban background site in Cyprus (Eastern Mediterranean); a region strongly impacted by climate change and air pollution. Here we identify unexpected high contribution of long-range transported pollution from fossil fuel sources in the Middle East, highlighting an urgent need to further characterize these fast-growing emissions and their impacts on regional atmospheric composition, climate, and health.
Ren-Guo Zhu, Hua-Yun Xiao, Liqin Cheng, Huixiao Zhu, Hongwei Xiao, and Yunyun Gong
Atmos. Chem. Phys., 22, 14019–14036, https://doi.org/10.5194/acp-22-14019-2022, https://doi.org/10.5194/acp-22-14019-2022, 2022
Short summary
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Sugars and amino acids are major classes of organic components in atmospheric fine particles and play important roles in the atmosphere. To identify their sources in different regions, the concentrations and compositions of sugar amino acids in fine particles were analysed. Our findings suggest that combining specific sugar tracers and chemical profiles of combined amino acids in local emission sources can identify various source characteristics of primary sources.
Hossein Dadashazar, Andrea F. Corral, Ewan Crosbie, Sanja Dmitrovic, Simon Kirschler, Kayla McCauley, Richard Moore, Claire Robinson, Joseph S. Schlosser, Michael Shook, K. Lee Thornhill, Christiane Voigt, Edward Winstead, Luke Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 22, 13897–13913, https://doi.org/10.5194/acp-22-13897-2022, https://doi.org/10.5194/acp-22-13897-2022, 2022
Short summary
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Multi-season airborne data over the northwestern Atlantic show that organic mass fraction and the relative amount of oxygenated organics within that fraction are enhanced in droplet residual particles as compared to particles below and above cloud. In-cloud aqueous processing is shown to be a potential driver of this compositional shift in cloud. This implies that aerosol–cloud interactions in the region reduce aerosol hygroscopicity due to the jump in the organic : sulfate ratio in cloud.
Min Zhou, Guangjie Zheng, Hongli Wang, Liping Qiao, Shuhui Zhu, DanDan Huang, Jingyu An, Shengrong Lou, Shikang Tao, Qian Wang, Rusha Yan, Yingge Ma, Changhong Chen, Yafang Cheng, Hang Su, and Cheng Huang
Atmos. Chem. Phys., 22, 13833–13844, https://doi.org/10.5194/acp-22-13833-2022, https://doi.org/10.5194/acp-22-13833-2022, 2022
Short summary
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The trend of aerosol pH and its drivers is crucial in understanding the multiphase formation pathways of aerosols. We reported the first trend analysis of aerosol pH from 2011 to 2019 in eastern China. Although significant variations of aerosol compositions were observed from 2011 to 2019, the aerosol pH estimated by model only slightly declined by 0.24. Our work shows that the opposite effects of SO42− and non-volatile cation changes play key roles in determining the moderate pH trend.
Zhenqi Xu, Wei Feng, Yicheng Wang, Haoran Ye, Yuhang Wang, Hong Liao, and Mingjie Xie
Atmos. Chem. Phys., 22, 13739–13752, https://doi.org/10.5194/acp-22-13739-2022, https://doi.org/10.5194/acp-22-13739-2022, 2022
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This work uses a solvent (DMF) that can efficiently dissolve low-volatility OC to examine BrC absorption and sources, which will benefit future investigations on the physicochemical properties of large organic molecules. The study results also shed light on potential sources for methanol-insoluble OC. These results highlight the importance of testing different solvents to investigate the structures and light absorption of low-volatility BrC.
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Short summary
We studied brown carbon aerosol during typical summer and winter periods in downtown Karlsruhe in southwestern Germany. The chromophore and chemical composition of brown carbon was determined by excitation–emission spectroscopy and mass spectrometry. The chromophore types and sources were substantially different in winter and summer. Humic-like chromophores of different degrees of oxidation dominated and were associated with molecules of different molecular weight and nitrogen content.
We studied brown carbon aerosol during typical summer and winter periods in downtown Karlsruhe...
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