Articles | Volume 14, issue 5
https://doi.org/10.5194/acp-14-2315-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-14-2315-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
05 Mar 2014
Research article |
| 05 Mar 2014
Influence of surface morphology on the immersion mode ice nucleation efficiency of hematite particles
N. Hiranuma
Institute for Meteorology and Climate Research – Atmospheric Aerosol Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
N. Hoffmann
Institute for Meteorology and Climate Research – Atmospheric Aerosol Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
A. Kiselev
Institute for Meteorology and Climate Research – Atmospheric Aerosol Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
A. Dreyer
Faculty of Chemistry, Bielefeld University, Bielefeld, Germany
now at: Institute Advanced Ceramics, Hamburg University of Technology, Hamburg, Germany
K. Zhang
Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
G. Kulkarni
Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington, USA
Faculty of Chemistry, Bielefeld University, Bielefeld, Germany
O. Möhler
Institute for Meteorology and Climate Research – Atmospheric Aerosol Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
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In this work, we present results from an Arctic field campaign (NASCENT) in Ny-Ålesund, Svalbard, on the abundance, variability, physicochemical properties, and potential sources of ice-nucleating particles (INPs) relevant for mixed-phase cloud formation. This work improves the data coverage of Arctic INPs and aerosol properties, allowing for the validation of models predicting cloud microphysical and radiative properties of mixed-phase clouds in the rapidly warming Arctic.
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Due to a high frequency of storm events, West Texas is an ideal location to study ice-nucleating particles (INPs) in severe precipitation. Our results present that cumulative INP concentration in our precipitation samples below −20 °C could be high in the samples collected while observing > 10 mm h−1 precipitation with notably large hydrometeor sizes and an implication of cattle feedyard bacteria inclusion. Marine bacteria were found in a subset of our precipitation and cattle feedyard samples.
Ottmar Möhler, Michael Adams, Larissa Lacher, Franziska Vogel, Jens Nadolny, Romy Ullrich, Cristian Boffo, Tatjana Pfeuffer, Achim Hobl, Maximilian Weiß, Hemanth S. K. Vepuri, Naruki Hiranuma, and Benjamin J. Murray
Atmos. Meas. Tech., 14, 1143–1166, https://doi.org/10.5194/amt-14-1143-2021, https://doi.org/10.5194/amt-14-1143-2021, 2021
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The Earth's climate is influenced by clouds, which are impacted by ice-nucleating particles (INPs), a minor fraction of atmospheric aerosols. INPs induce ice formation in clouds and thus often initiate precipitation formation. The Portable Ice Nucleation Experiment (PINE) is the first fully automated instrument to study cloud ice formation and to obtain long-term records of INPs. This is a timely development, and the capabilities it offers for research and atmospheric monitoring are significant.
Gourihar Kulkarni, Naruki Hiranuma, Ottmar Möhler, Kristina Höhler, Swarup China, Daniel J. Cziczo, and Paul J. DeMott
Atmos. Meas. Tech., 13, 6631–6643, https://doi.org/10.5194/amt-13-6631-2020, https://doi.org/10.5194/amt-13-6631-2020, 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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Naruki Hiranuma, Kouji Adachi, David M. Bell, Franco Belosi, Hassan Beydoun, Bhaskar Bhaduri, Heinz Bingemer, Carsten Budke, Hans-Christian Clemen, Franz Conen, Kimberly M. Cory, Joachim Curtius, Paul J. DeMott, Oliver Eppers, Sarah Grawe, Susan Hartmann, Nadine Hoffmann, Kristina Höhler, Evelyn Jantsch, Alexei Kiselev, Thomas Koop, Gourihar Kulkarni, Amelie Mayer, Masataka Murakami, Benjamin J. Murray, Alessia Nicosia, Markus D. Petters, Matteo Piazza, Michael Polen, Naama Reicher, Yinon Rudich, Atsushi Saito, Gianni Santachiara, Thea Schiebel, Gregg P. Schill, Johannes Schneider, Lior Segev, Emiliano Stopelli, Ryan C. Sullivan, Kaitlyn Suski, Miklós Szakáll, Takuya Tajiri, Hans Taylor, Yutaka Tobo, Romy Ullrich, Daniel Weber, Heike Wex, Thomas F. Whale, Craig L. Whiteside, Katsuya Yamashita, Alla Zelenyuk, and Ottmar Möhler
Atmos. Chem. Phys., 19, 4823–4849, https://doi.org/10.5194/acp-19-4823-2019, https://doi.org/10.5194/acp-19-4823-2019, 2019
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Kaitlyn J. Suski, David M. Bell, Naruki Hiranuma, Ottmar Möhler, Dan Imre, and Alla Zelenyuk
Atmos. Chem. Phys., 18, 17497–17513, https://doi.org/10.5194/acp-18-17497-2018, https://doi.org/10.5194/acp-18-17497-2018, 2018
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Paul J. DeMott, Ottmar Möhler, Daniel J. Cziczo, Naruki Hiranuma, Markus D. Petters, Sarah S. Petters, Franco Belosi, Heinz G. Bingemer, Sarah D. Brooks, Carsten Budke, Monika Burkert-Kohn, Kristen N. Collier, Anja Danielczok, Oliver Eppers, Laura Felgitsch, Sarvesh Garimella, Hinrich Grothe, Paul Herenz, Thomas C. J. Hill, Kristina Höhler, Zamin A. Kanji, Alexei Kiselev, Thomas Koop, Thomas B. Kristensen, Konstantin Krüger, Gourihar Kulkarni, Ezra J. T. Levin, Benjamin J. Murray, Alessia Nicosia, Daniel O'Sullivan, Andreas Peckhaus, Michael J. Polen, Hannah C. Price, Naama Reicher, Daniel A. Rothenberg, Yinon Rudich, Gianni Santachiara, Thea Schiebel, Jann Schrod, Teresa M. Seifried, Frank Stratmann, Ryan C. Sullivan, Kaitlyn J. Suski, Miklós Szakáll, Hans P. Taylor, Romy Ullrich, Jesus Vergara-Temprado, Robert Wagner, Thomas F. Whale, Daniel Weber, André Welti, Theodore W. Wilson, Martin J. Wolf, and Jake Zenker
Atmos. Meas. Tech., 11, 6231–6257, https://doi.org/10.5194/amt-11-6231-2018, https://doi.org/10.5194/amt-11-6231-2018, 2018
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The ability to measure ice nucleating particles is vital to quantifying their role in affecting clouds and precipitation. Methods for measuring droplet freezing were compared while co-sampling relevant particle types. Measurement correspondence was very good for ice nucleating particles of bacterial and natural soil origin, and somewhat more disparate for those of mineral origin. Results reflect recently improved capabilities and provide direction toward addressing remaining measurement issues.
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.
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.
H. Wex, S. Augustin-Bauditz, Y. Boose, C. Budke, J. Curtius, K. Diehl, A. Dreyer, F. Frank, S. Hartmann, N. Hiranuma, E. Jantsch, Z. A. Kanji, A. Kiselev, T. Koop, O. Möhler, D. Niedermeier, B. Nillius, M. Rösch, D. Rose, C. Schmidt, I. Steinke, and F. Stratmann
Atmos. Chem. Phys., 15, 1463–1485, https://doi.org/10.5194/acp-15-1463-2015, https://doi.org/10.5194/acp-15-1463-2015, 2015
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Immersion freezing measurements from seven different measurement techniques were intercompared using a biological ice nucleating material from bacteria. Although different techniques examined differently concentrated droplets, it was possible to find a uniform description, which showed that results from all experiments were generally in good agreement and were also in agreement with parameterizations published earlier in literature.
N. Hiranuma, M. Paukert, I. Steinke, K. Zhang, G. Kulkarni, C. Hoose, M. Schnaiter, H. Saathoff, and O. Möhler
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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.
Fan Mei, Qi Zhang, Damao Zhang, Jerome Fast, Gourihar Kulkarni, Mikhail Pekour, Christopher Niedek, Susanne Glienke, Isarel Silber, Beat Schmid, Jason Tomlinson, Hardeep Mehta, Xena Mansoura, Zezhen Cheng, Gregory Vandergrift, Nurun Nahar Lata, Swarup China, and Zihua Zhu
EGUsphere, https://doi.org/10.5194/egusphere-2024-3089, https://doi.org/10.5194/egusphere-2024-3089, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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This study highlights the unique capability of the ArcticShark UAS in measuring vertically resolved atmospheric properties over the Southern Great Plains. Data from 32 research flights in 2023 reveal seasonal patterns and correlations with conventional measurements. The consistency and complementarity of in situ and remote sensing methods are highlighted. The study demonstrates the ArcticShark’s versatility in bridging data gaps and improving the understanding of vertical atmospheric structures.
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.
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.
Xiaoli Shen, David M. Bell, Hugh Coe, Naruki Hiranuma, Fabian Mahrt, Nicholas A. Marsden, Claudia Mohr, Daniel M. Murphy, Harald Saathoff, Johannes Schneider, Jacqueline Wilson, Maria A. Zawadowicz, Alla Zelenyuk, Paul J. DeMott, Ottmar Möhler, and Daniel J. Cziczo
Atmos. Chem. Phys., 24, 10869–10891, https://doi.org/10.5194/acp-24-10869-2024, https://doi.org/10.5194/acp-24-10869-2024, 2024
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Kunfeng Gao, Franziska Vogel, Romanos Foskinis, Stergios Vratolis, Maria I. Gini, Konstantinos Granakis, Anne-Claire Billault-Roux, Paraskevi Georgakaki, Olga Zografou, Prodromos Fetfatzis, Alexis Berne, Alexandros Papayannis, Konstantinos Eleftheridadis, Ottmar Möhler, and Athanasios Nenes
Atmos. Chem. Phys., 24, 9939–9974, https://doi.org/10.5194/acp-24-9939-2024, https://doi.org/10.5194/acp-24-9939-2024, 2024
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Ice nucleating particle (INP) concentrations are required for correct predictions of clouds and precipitation in a changing climate, but they are poorly constrained in climate models. We unravel source contributions to INPs in the eastern Mediterranean and find that biological particles are important, regardless of their origin. The parameterizations developed exhibit superior performance and enable models to consider biological-particle effects on INPs.
Alexander Julian Böhmländer, Larissa Lacher, David Brus, Konstantinos-Matthaios Doulgeris, Zoé Brasseur, Matthew Boyer, Joel Kuula, Thomas Leisner, and Ottmar Möhler
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-120, https://doi.org/10.5194/amt-2024-120, 2024
Preprint under review for AMT
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Clouds and aerosol are important for weather and climate. Typically, pure water cloud droplets stay liquid until around -35 °C, unless they come into contact with ice-nucleating particles (INPs). INPs are a rare subset of aerosol particles. Using uncrewed aerial vehicles (UAVs), it is possible to collect aerosol particles and analyse them on their ice-nucleating ability. This study describes the test and validation of a sampling setup that can be used to collect aerosol particles onto a filter.
Paul DeMott, Jessica Mirrielees, Sarah Petters, Daniel Cziczo, Markus Petters, Heinz Bingemer, Thomas Hill, Karl Froyd, Sarvesh Garimella, Gannet Hallar, Ezra Levin, Ian McCubbin, Anne Perring, Christopher Rapp, Thea Schiebel, Jann Schrod, Kaitlyn Suski, Daniel Weber, Martin Wolf, Maria Zawadowicz, Jake Zenker, Ottmar Möhler, and Sarah Brooks
EGUsphere, https://doi.org/10.5194/egusphere-2024-1744, https://doi.org/10.5194/egusphere-2024-1744, 2024
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The Fifth International Ice Nucleation Workshop 3rd Phase (FIN-03) compared the ambient atmospheric performance of ice nucleating particle (INP) measuring systems and explored general methods for discerning atmospheric INP compositions. Mirroring laboratory results, most measurements agreed within one order of magnitude. Measurements of total aerosol properties and investigations of INP compositions supported a dominant role of soil and plant organic aerosol elements as INPs during the study.
Elise K. Wilbourn, Larissa Lacher, Carlos Guerrero, Hemanth S. K. Vepuri, Kristina Höhler, Jens Nadolny, Aidan D. Pantoya, Ottmar Möhler, and Naruki Hiranuma
Atmos. Chem. Phys., 24, 5433–5456, https://doi.org/10.5194/acp-24-5433-2024, https://doi.org/10.5194/acp-24-5433-2024, 2024
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Ambient ice particles were measured at terrestrial and temperate marine sites. Ice particles were more abundant in the former site, while the fraction of ice particles relative to total ambient particles, representing atmospheric ice nucleation efficiency, was higher in the latter site. Ice nucleation parameterizations were developed as a function of examined freezing temperatures from two sites for our study periods (autumn).
Johanna S. Seidel, Alexei A. Kiselev, Alice Keinert, Frank Stratmann, Thomas Leisner, and Susan Hartmann
Atmos. Chem. Phys., 24, 5247–5263, https://doi.org/10.5194/acp-24-5247-2024, https://doi.org/10.5194/acp-24-5247-2024, 2024
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Clouds often contain several thousand times more ice crystals than aerosol particles catalyzing ice formation. This phenomenon, commonly known as ice multiplication, is often explained by secondary ice formation due to the collisions between falling ice particles and droplets. In this study, we mimic this riming process. Contrary to earlier experiments, we found no efficient ice multiplication, which fundamentally questions the importance of the rime-splintering mechanism.
Eugene F. Mikhailov, Sergey S. Vlasenko, and Alexei A. Kiselev
Atmos. Chem. Phys., 24, 2971–2984, https://doi.org/10.5194/acp-24-2971-2024, https://doi.org/10.5194/acp-24-2971-2024, 2024
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Surface tension and water activity are key thermodynamic parameters determining the impact of atmospheric aerosols on human health and climate. However, these parameters are not well constrained for nanoparticles composed of organic and inorganic compounds. In this study, we determined for the first time the water activity and surface tension of mixed organic/inorganic nanodroplets by applying a differential Köhler analysis (DKA) to hygroscopic growth measurements.
Larissa Lacher, Michael P. Adams, Kevin Barry, Barbara Bertozzi, Heinz Bingemer, Cristian Boffo, Yannick Bras, Nicole Büttner, Dimitri Castarede, Daniel J. Cziczo, Paul J. DeMott, Romy Fösig, Megan Goodell, Kristina Höhler, Thomas C. J. Hill, Conrad Jentzsch, Luis A. Ladino, Ezra J. T. Levin, Stephan Mertes, Ottmar Möhler, Kathryn A. Moore, Benjamin J. Murray, Jens Nadolny, Tatjana Pfeuffer, David Picard, Carolina Ramírez-Romero, Mickael Ribeiro, Sarah Richter, Jann Schrod, Karine Sellegri, Frank Stratmann, Benjamin E. Swanson, Erik S. Thomson, Heike Wex, Martin J. Wolf, and Evelyn Freney
Atmos. Chem. Phys., 24, 2651–2678, https://doi.org/10.5194/acp-24-2651-2024, https://doi.org/10.5194/acp-24-2651-2024, 2024
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Aerosol particles that trigger ice formation in clouds are important for the climate system but are very rare in the atmosphere, challenging measurement techniques. Here we compare three cloud chambers and seven methods for collecting aerosol particles on filters for offline analysis at a mountaintop station. A general good agreement of the methods was found when sampling aerosol particles behind a whole air inlet, supporting their use for obtaining data that can be implemented in models.
Rolf Müller, Ulrich Pöschl, Thomas Koop, Thomas Peter, and Ken Carslaw
Atmos. Chem. Phys., 23, 15445–15453, https://doi.org/10.5194/acp-23-15445-2023, https://doi.org/10.5194/acp-23-15445-2023, 2023
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Paul J. Crutzen was a pioneer in atmospheric sciences and a kind-hearted, humorous person with empathy for the private lives of his colleagues and students. He made fundamental scientific contributions to a wide range of scientific topics in all parts of the atmosphere. Paul was among the founders of the journal Atmospheric Chemistry and Physics. His work will continue to be a guide for generations of scientists and environmental policymakers to come.
Mohit Singh, Stephanie Helen Jones, Alexei Kiselev, Denis Duft, and Thomas Leisner
Atmos. Meas. Tech., 16, 5205–5215, https://doi.org/10.5194/amt-16-5205-2023, https://doi.org/10.5194/amt-16-5205-2023, 2023
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We introduce a novel method for simultaneous measurement of the viscosity and surface tension of metastable liquids. Our approach is based on the phase analysis of excited shape oscillations in levitated droplets. It is applicable to a wide range of atmospheric conditions and can monitor changes in real time. The technique holds great promise for investigating the effect of atmospheric processing on the viscosity and surface tension of solution droplets in equilibrium with water vapour.
Guangyu Li, Elise K. Wilbourn, Zezhen Cheng, Jörg Wieder, Allison Fagerson, Jan Henneberger, Ghislain Motos, Rita Traversi, Sarah D. Brooks, Mauro Mazzola, Swarup China, Athanasios Nenes, Ulrike Lohmann, Naruki Hiranuma, and Zamin A. Kanji
Atmos. Chem. Phys., 23, 10489–10516, https://doi.org/10.5194/acp-23-10489-2023, https://doi.org/10.5194/acp-23-10489-2023, 2023
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In this work, we present results from an Arctic field campaign (NASCENT) in Ny-Ålesund, Svalbard, on the abundance, variability, physicochemical properties, and potential sources of ice-nucleating particles (INPs) relevant for mixed-phase cloud formation. This work improves the data coverage of Arctic INPs and aerosol properties, allowing for the validation of models predicting cloud microphysical and radiative properties of mixed-phase clouds in the rapidly warming Arctic.
Robert Wagner, Alexander D. James, Victoria L. Frankland, Ottmar Möhler, Benjamin J. Murray, John M. C. Plane, Harald Saathoff, Ralf Weigel, and Martin Schnaiter
Atmos. Chem. Phys., 23, 6789–6811, https://doi.org/10.5194/acp-23-6789-2023, https://doi.org/10.5194/acp-23-6789-2023, 2023
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Polar stratospheric clouds (PSCs) play an important role in the depletion of stratospheric ozone. They can consist of different chemical species, including crystalline nitric acid hydrates. We found that mineral dust or meteoric ablation material can efficiently catalyse the formation of a specific phase of nitric acid dihydrate crystals. We determined predominant particle shapes and infrared optical properties of these crystals, which are important inputs for remote sensing detection of PSCs.
Kara D. Lamb, Jerry Y. Harrington, Benjamin W. Clouser, Elisabeth J. Moyer, Laszlo Sarkozy, Volker Ebert, Ottmar Möhler, and Harald Saathoff
Atmos. Chem. Phys., 23, 6043–6064, https://doi.org/10.5194/acp-23-6043-2023, https://doi.org/10.5194/acp-23-6043-2023, 2023
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This study investigates how ice grows directly from vapor in cirrus clouds by comparing observations of populations of ice crystals growing in a cloud chamber against models developed in the context of single-crystal laboratory studies. We demonstrate that previous discrepancies between different experimental measurements do not necessarily point to different physical interpretations but are rather due to assumptions that were made in terms of how experiments were modeled in previous studies.
Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, James Harnwell, Simon P. Alexander, Andrew R. Klekociuk, Keiichiro Hara, Ian M. McRobert, Alain Protat, Joel Alroe, Luke T. Cravigan, Branka Miljevic, Zoran D. Ristovski, Robyn Schofield, Stephen R. Wilson, Connor J. Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Greg M. McFarquhar, Scott D. Chambers, Alastair G. Williams, and Alan D. Griffiths
Atmos. Chem. Phys., 23, 3749–3777, https://doi.org/10.5194/acp-23-3749-2023, https://doi.org/10.5194/acp-23-3749-2023, 2023
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Observations of aerosols in pristine regions are rare but are vital to constraining the natural baseline from which climate simulations are calculated. Here we present recent seasonal observations of aerosols from the Southern Ocean and contrast them with measurements from Antarctica, Australia and regionally relevant voyages. Strong seasonal cycles persist, but striking differences occur at different latitudes. This study highlights the need for more long-term observations in remote regions.
Lukas Eickhoff, Maddalena Bayer-Giraldi, Naama Reicher, Yinon Rudich, and Thomas Koop
Biogeosciences, 20, 1–14, https://doi.org/10.5194/bg-20-1-2023, https://doi.org/10.5194/bg-20-1-2023, 2023
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The formation of ice is an important process in Earth’s atmosphere, biosphere, and cryosphere, in particular in polar regions. Our research focuses on the influence of the sea ice diatom Fragilariopsis cylindrus and of molecules produced by it upon heterogenous ice nucleation. For that purpose, we studied the freezing of tiny droplets containing the diatoms in a microfluidic device. Together with previous studies, our results suggest a common freezing behaviour of various sea ice diatoms.
Outi Meinander, Pavla Dagsson-Waldhauserova, Pavel Amosov, Elena Aseyeva, Cliff Atkins, Alexander Baklanov, Clarissa Baldo, Sarah L. Barr, Barbara Barzycka, Liane G. Benning, Bojan Cvetkovic, Polina Enchilik, Denis Frolov, Santiago Gassó, Konrad Kandler, Nikolay Kasimov, Jan Kavan, James King, Tatyana Koroleva, Viktoria Krupskaya, Markku Kulmala, Monika Kusiak, Hanna K. Lappalainen, Michał Laska, Jerome Lasne, Marek Lewandowski, Bartłomiej Luks, James B. McQuaid, Beatrice Moroni, Benjamin Murray, Ottmar Möhler, Adam Nawrot, Slobodan Nickovic, Norman T. O’Neill, Goran Pejanovic, Olga Popovicheva, Keyvan Ranjbar, Manolis Romanias, Olga Samonova, Alberto Sanchez-Marroquin, Kerstin Schepanski, Ivan Semenkov, Anna Sharapova, Elena Shevnina, Zongbo Shi, Mikhail Sofiev, Frédéric Thevenet, Throstur Thorsteinsson, Mikhail Timofeev, Nsikanabasi Silas Umo, Andreas Uppstu, Darya Urupina, György Varga, Tomasz Werner, Olafur Arnalds, and Ana Vukovic Vimic
Atmos. Chem. Phys., 22, 11889–11930, https://doi.org/10.5194/acp-22-11889-2022, https://doi.org/10.5194/acp-22-11889-2022, 2022
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High-latitude dust (HLD) is a short-lived climate forcer, air pollutant, and nutrient source. Our results suggest a northern HLD belt at 50–58° N in Eurasia and 50–55° N in Canada and at >60° N in Eurasia and >58° N in Canada. Our addition to the previously identified global dust belt (GDB) provides crucially needed information on the extent of active HLD sources with both direct and indirect impacts on climate and environment in remote regions, which are often poorly understood and predicted.
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.
Zoé Brasseur, Dimitri Castarède, Erik S. Thomson, Michael P. Adams, Saskia Drossaart van Dusseldorp, Paavo Heikkilä, Kimmo Korhonen, Janne Lampilahti, Mikhail Paramonov, Julia Schneider, Franziska Vogel, Yusheng Wu, Jonathan P. D. Abbatt, Nina S. Atanasova, Dennis H. Bamford, Barbara Bertozzi, Matthew Boyer, David Brus, Martin I. Daily, Romy Fösig, Ellen Gute, Alexander D. Harrison, Paula Hietala, Kristina Höhler, Zamin A. Kanji, Jorma Keskinen, Larissa Lacher, Markus Lampimäki, Janne Levula, Antti Manninen, Jens Nadolny, Maija Peltola, Grace C. E. Porter, Pyry Poutanen, Ulrike Proske, Tobias Schorr, Nsikanabasi Silas Umo, János Stenszky, Annele Virtanen, Dmitri Moisseev, Markku Kulmala, Benjamin J. Murray, Tuukka Petäjä, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 5117–5145, https://doi.org/10.5194/acp-22-5117-2022, https://doi.org/10.5194/acp-22-5117-2022, 2022
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The present measurement report introduces the ice nucleation campaign organized in Hyytiälä, Finland, in 2018 (HyICE-2018). We provide an overview of the campaign settings, and we describe the measurement infrastructure and operating procedures used. In addition, we use results from ice nucleation instrument inter-comparison to show that the suite of these instruments deployed during the campaign reports consistent results.
Manuel Baumgartner, Christian Rolf, Jens-Uwe Grooß, Julia Schneider, Tobias Schorr, Ottmar Möhler, Peter Spichtinger, and Martina Krämer
Atmos. Chem. Phys., 22, 65–91, https://doi.org/10.5194/acp-22-65-2022, https://doi.org/10.5194/acp-22-65-2022, 2022
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An important mechanism for the appearance of ice particles in the upper troposphere at low temperatures is homogeneous nucleation. This process is commonly described by the
Koop line, predicting the humidity at freezing. However, laboratory measurements suggest that the freezing humidities are above the Koop line, motivating the present study to investigate the influence of different physical parameterizations on the homogeneous freezing with the help of a detailed numerical model.
Lucía Caudillo, Birte Rörup, Martin Heinritzi, Guillaume Marie, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Antonio Amorim, Farnoush Ataei, Rima Baalbaki, Barbara Bertozzi, Zoé Brasseur, Randall Chiu, Biwu Chu, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Loïc Gonzalez Carracedo, Xu-Cheng He, Victoria Hofbauer, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Brandon Lopez, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Dario Massabò, Roy L. Mauldin, Bernhard Mentler, Ugo Molteni, Antti Onnela, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Meredith Schervish, Wiebke Scholz, Benjamin Schulze, Jiali Shen, Dominik Stolzenburg, Yuri Stozhkov, Mihnea Surdu, Christian Tauber, Yee Jun Tham, Ping Tian, António Tomé, Steffen Vogt, Mingyi Wang, Dongyu S. Wang, Stefan K. Weber, André Welti, Wang Yonghong, Wu Yusheng, Marcel Zauner-Wieczorek, Urs Baltensperger, Imad El Haddad, Richard C. Flagan, Armin Hansel, Kristina Höhler, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Ottmar Möhler, Harald Saathoff, Rainer Volkamer, Paul M. Winkler, Neil M. Donahue, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys., 21, 17099–17114, https://doi.org/10.5194/acp-21-17099-2021, https://doi.org/10.5194/acp-21-17099-2021, 2021
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We performed experiments in the CLOUD chamber at CERN at low temperatures to simulate new particle formation in the upper free troposphere (at −30 ºC and −50 ºC). We measured the particle and gas phase and found that most of the compounds present in the gas phase are detected as well in the particle phase. The major compounds in the particles are C8–10 and C18–20. Specifically, we showed that C5 and C15 compounds are detected in a mixed system with isoprene and α-pinene at −30 ºC, 20 % RH.
Larissa Lacher, Hans-Christian Clemen, Xiaoli Shen, Stephan Mertes, Martin Gysel-Beer, Alireza Moallemi, Martin Steinbacher, Stephan Henne, Harald Saathoff, Ottmar Möhler, Kristina Höhler, Thea Schiebel, Daniel Weber, Jann Schrod, Johannes Schneider, and Zamin A. Kanji
Atmos. Chem. Phys., 21, 16925–16953, https://doi.org/10.5194/acp-21-16925-2021, https://doi.org/10.5194/acp-21-16925-2021, 2021
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We investigate ice-nucleating particle properties at Jungfraujoch during the 2017 joint INUIT/CLACE field campaign, to improve the knowledge about those rare particles in a cloud-relevant environment. By quantifying ice-nucleating particles in parallel to single-particle mass spectrometry measurements, we find that mineral dust and aged sea spray particles are potential candidates for ice-nucleating particles. Our findings are supported by ice residual analysis and source region modeling.
Matteo Rinaldi, Naruki Hiranuma, Gianni Santachiara, Mauro Mazzola, Karam Mansour, Marco Paglione, Cheyanne A. Rodriguez, Rita Traversi, Silvia Becagli, David Cappelletti, and Franco Belosi
Atmos. Chem. Phys., 21, 14725–14748, https://doi.org/10.5194/acp-21-14725-2021, https://doi.org/10.5194/acp-21-14725-2021, 2021
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This study aims to add to the still scant ice-nucleating particle (INP) observations in the Arctic environment, investigating INP concentrations and potential sources, during spring and summertime, at the ground-level site of GVB. The lack of a clear concentration seasonal trend, in contrast with previous works, shows an important interannual variability of Arctic INP sources, which may be both terrestrial and marine, outside the Arctic haze period.
Haoran Li, Ottmar Möhler, Tuukka Petäjä, and Dmitri Moisseev
Atmos. Chem. Phys., 21, 14671–14686, https://doi.org/10.5194/acp-21-14671-2021, https://doi.org/10.5194/acp-21-14671-2021, 2021
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In natural clouds, ice-nucleating particles are expected to be rare above –10 °C. In the current paper, we found that the formation of ice columns is frequent in stratiform clouds and is associated with increased precipitation intensity and liquid water path. In single-layer shallow clouds, the production of ice columns was attributed to secondary ice production, despite the rime-splintering process not being expected to take place in such clouds.
Julia Schneider, Kristina Höhler, Robert Wagner, Harald Saathoff, Martin Schnaiter, Tobias Schorr, Isabelle Steinke, Stefan Benz, Manuel Baumgartner, Christian Rolf, Martina Krämer, Thomas Leisner, and Ottmar Möhler
Atmos. Chem. Phys., 21, 14403–14425, https://doi.org/10.5194/acp-21-14403-2021, https://doi.org/10.5194/acp-21-14403-2021, 2021
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Homogeneous freezing is a relevant mechanism for the formation of cirrus clouds in the upper troposphere. Based on an extensive set of homogeneous freezing experiments at the AIDA chamber with aqueous sulfuric acid aerosol, we provide a new fit line for homogeneous freezing onset conditions of sulfuric acid aerosol focusing on cirrus temperatures. In the atmosphere, homogeneous freezing thresholds have important implications on the cirrus cloud occurrence and related cloud radiative effects.
Naruki Hiranuma, Brent W. Auvermann, Franco Belosi, Jack Bush, Kimberly M. Cory, Dimitrios G. Georgakopoulos, Kristina Höhler, Yidi Hou, Larissa Lacher, Harald Saathoff, Gianni Santachiara, Xiaoli Shen, Isabelle Steinke, Romy Ullrich, Nsikanabasi S. Umo, Hemanth S. K. Vepuri, Franziska Vogel, and Ottmar Möhler
Atmos. Chem. Phys., 21, 14215–14234, https://doi.org/10.5194/acp-21-14215-2021, https://doi.org/10.5194/acp-21-14215-2021, 2021
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We present laboratory and field studies showing that an open-lot livestock facility is a substantial source of atmospheric ice-nucleating particles (INPs). The ambient concentration of INPs from livestock facilities in Texas is very high. It is up to several thousand INPs per liter below –20 °C and may impact regional aerosol–cloud interactions. About 50% of feedlot INPs were supermicron in diameter. No notable amount of known ice-nucleating microorganisms was found in our feedlot samples.
Robert Wagner, Luisa Ickes, Allan K. Bertram, Nora Els, Elena Gorokhova, Ottmar Möhler, Benjamin J. Murray, Nsikanabasi Silas Umo, and Matthew E. Salter
Atmos. Chem. Phys., 21, 13903–13930, https://doi.org/10.5194/acp-21-13903-2021, https://doi.org/10.5194/acp-21-13903-2021, 2021
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Sea spray aerosol particles are a mixture of inorganic salts and organic matter from phytoplankton organisms. At low temperatures in the upper troposphere, both inorganic and organic constituents can induce the formation of ice crystals and thereby impact cloud properties and climate. In this study, we performed experiments in a cloud simulation chamber with particles produced from Arctic seawater samples to quantify the relative contribution of inorganic and organic species in ice formation.
Ruhi S. Humphries, Melita D. Keywood, Sean Gribben, Ian M. McRobert, Jason P. Ward, Paul Selleck, Sally Taylor, James Harnwell, Connor Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Alain Protat, Simon P. Alexander, and Greg McFarquhar
Atmos. Chem. Phys., 21, 12757–12782, https://doi.org/10.5194/acp-21-12757-2021, https://doi.org/10.5194/acp-21-12757-2021, 2021
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The Southern Ocean region is one of the most pristine in the world and serves as an important proxy for the pre-industrial atmosphere. Improving our understanding of the natural processes in this region is likely to result in the largest reductions in the uncertainty of climate and earth system models. In this paper we present a statistical summary of the latitudinal gradient of aerosol and cloud condensation nuclei concentrations obtained from five voyages spanning the Southern Ocean.
Alexei A. Kiselev, Alice Keinert, Tilia Gaedeke, Thomas Leisner, Christoph Sutter, Elena Petrishcheva, and Rainer Abart
Atmos. Chem. Phys., 21, 11801–11814, https://doi.org/10.5194/acp-21-11801-2021, https://doi.org/10.5194/acp-21-11801-2021, 2021
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Alkali feldspar is the most abundant mineral in the Earth's crust and is often present in mineral dust aerosols that are responsible for the formation of rain and snow in clouds. However, the cloud droplets containing pure potassium-rich feldspar would not freeze unless cooled down to a very low temperature. Here we show that partly replacing potassium with sodium would induce fracturing of feldspar, exposing a crystalline surface that could initiate freezing at higher temperature.
Barbara Bertozzi, Robert Wagner, Junwei Song, Kristina Höhler, Joschka Pfeifer, Harald Saathoff, Thomas Leisner, and Ottmar Möhler
Atmos. Chem. Phys., 21, 10779–10798, https://doi.org/10.5194/acp-21-10779-2021, https://doi.org/10.5194/acp-21-10779-2021, 2021
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Internally mixed particles composed of sulfate and organics are among the most abundant aerosol types. Their ice nucleation (IN) ability influences the formation of cirrus and, thus, the climate. We show that the presence of a thin organic coating suppresses the heterogeneous IN ability of crystalline ammonium sulfate particles. However, the IN ability of the same particle can substantially change if subjected to atmospheric processing, mainly due to differences in the resulting morphology.
Eugene F. Mikhailov, Mira L. Pöhlker, Kathrin Reinmuth-Selzle, Sergey S. Vlasenko, Ovid O. Krüger, Janine Fröhlich-Nowoisky, Christopher Pöhlker, Olga A. Ivanova, Alexey A. Kiselev, Leslie A. Kremper, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 6999–7022, https://doi.org/10.5194/acp-21-6999-2021, https://doi.org/10.5194/acp-21-6999-2021, 2021
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Subpollen particles are a relatively new subset of atmospheric aerosol particles. When pollen grains rupture, they release cytoplasmic fragments known as subpollen particles (SPPs). We found that SPPs, containing a broad spectrum of biopolymers and hydrocarbons, exhibit abnormally high water uptake. This effect may influence the life cycle of SPPs and the related direct and indirect impacts on radiation budget as well as reinforce their allergic potential.
Hemanth S. K. Vepuri, Cheyanne A. Rodriguez, Dimitrios G. Georgakopoulos, Dustin Hume, James Webb, Gregory D. Mayer, and Naruki Hiranuma
Atmos. Chem. Phys., 21, 4503–4520, https://doi.org/10.5194/acp-21-4503-2021, https://doi.org/10.5194/acp-21-4503-2021, 2021
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Due to a high frequency of storm events, West Texas is an ideal location to study ice-nucleating particles (INPs) in severe precipitation. Our results present that cumulative INP concentration in our precipitation samples below −20 °C could be high in the samples collected while observing > 10 mm h−1 precipitation with notably large hydrometeor sizes and an implication of cattle feedyard bacteria inclusion. Marine bacteria were found in a subset of our precipitation and cattle feedyard samples.
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
Atmos. Chem. Phys., 21, 3899–3918, https://doi.org/10.5194/acp-21-3899-2021, https://doi.org/10.5194/acp-21-3899-2021, 2021
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By triggering the formation of ice crystals, ice-nucleating particles (INP) strongly influence cloud formation. Continuous, long-term measurements are needed to characterize the atmospheric INP variability. Here, a first long-term time series of INP spectra measured in the boreal forest for more than 1 year is presented, showing a clear seasonal cycle. It is shown that the seasonal dependency of INP concentrations and prevalent INP types is driven by the abundance of biogenic aerosol.
Robert Wagner, Baptiste Testa, Michael Höpfner, Alexei Kiselev, Ottmar Möhler, Harald Saathoff, Jörn Ungermann, and Thomas Leisner
Atmos. Meas. Tech., 14, 1977–1991, https://doi.org/10.5194/amt-14-1977-2021, https://doi.org/10.5194/amt-14-1977-2021, 2021
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During the Asian summer monsoon period, air pollutants are transported from layers near the ground to high altitudes of 13 to 18 km in the atmosphere. Infrared measurements have shown that particles composed of solid ammonium nitrate are a major part of these pollutants. To enable the quantitative analysis of the infrared spectra, we have determined for the first time accurate optical constants of ammonium nitrate for the low-temperature conditions of the upper atmosphere.
Ottmar Möhler, Michael Adams, Larissa Lacher, Franziska Vogel, Jens Nadolny, Romy Ullrich, Cristian Boffo, Tatjana Pfeuffer, Achim Hobl, Maximilian Weiß, Hemanth S. K. Vepuri, Naruki Hiranuma, and Benjamin J. Murray
Atmos. Meas. Tech., 14, 1143–1166, https://doi.org/10.5194/amt-14-1143-2021, https://doi.org/10.5194/amt-14-1143-2021, 2021
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The Earth's climate is influenced by clouds, which are impacted by ice-nucleating particles (INPs), a minor fraction of atmospheric aerosols. INPs induce ice formation in clouds and thus often initiate precipitation formation. The Portable Ice Nucleation Experiment (PINE) is the first fully automated instrument to study cloud ice formation and to obtain long-term records of INPs. This is a timely development, and the capabilities it offers for research and atmospheric monitoring are significant.
Gourihar Kulkarni, Naruki Hiranuma, Ottmar Möhler, Kristina Höhler, Swarup China, Daniel J. Cziczo, and Paul J. DeMott
Atmos. Meas. Tech., 13, 6631–6643, https://doi.org/10.5194/amt-13-6631-2020, https://doi.org/10.5194/amt-13-6631-2020, 2020
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This study presents a new continuous-flow-diffusion-chamber-style operated ice chamber (Modified Compact Ice Chamber, MCIC) to measure the immersion-freezing efficiency of atmospheric particles. MCIC allowed us to obtain maximum droplet-freezing efficiency at higher time resolution without droplet breakthrough ambiguity. Its evaluation was performed by reproducing published data from the recent ice nucleation workshop and past laboratory data for standard and airborne ice-nucleating particles.
Matthew Fraund, Daniel J. Bonanno, Swarup China, Don Q. Pham, Daniel Veghte, Johannes Weis, Gourihar Kulkarni, Ken Teske, Mary K. Gilles, Alexander Laskin, and Ryan C. Moffet
Atmos. Chem. Phys., 20, 11593–11606, https://doi.org/10.5194/acp-20-11593-2020, https://doi.org/10.5194/acp-20-11593-2020, 2020
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High viscosity organic particles (HVOPs) in the Southern Great Plains have been analyzed, and two particle types were found. Previously studied tar balls and the recently discovered airborne soil organic particles (ASOPs) are both shown to be brown carbon (BrC). These particle types can be identified in bulk by an absorption Ångström exponent approaching 2.6. HVOP types can be differentiated by comparing carbon absorption spectrum peak ratios between the carboxylic acid, alcohol, and sp2 peaks.
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.
Luisa Ickes, Grace C. E. Porter, Robert Wagner, Michael P. Adams, Sascha Bierbauer, Allan K. Bertram, Merete Bilde, Sigurd Christiansen, Annica M. L. Ekman, Elena Gorokhova, Kristina Höhler, Alexei A. Kiselev, Caroline Leck, Ottmar Möhler, Benjamin J. Murray, Thea Schiebel, Romy Ullrich, and Matthew E. Salter
Atmos. Chem. Phys., 20, 11089–11117, https://doi.org/10.5194/acp-20-11089-2020, https://doi.org/10.5194/acp-20-11089-2020, 2020
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The Arctic is a region where aerosols are scarce. Sea spray might be a potential source of aerosols acting as ice-nucleating particles. We investigate two common phytoplankton species (Melosira arctica and Skeletonema marinoi) and present their ice nucleation activity in comparison with Arctic seawater microlayer samples from different field campaigns. We also aim to understand the aerosolization process of marine biological samples and the potential effect on the ice nucleation activity.
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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Previous measurements of water vapor in the upper troposphere and lower stratosphere (UT/LS) have shown unexpectedly high concentrations of water vapor in ice clouds, which may be due to an incomplete understanding of the structure of ice and the behavior of ice growth in this part of the atmosphere. Water vapor measurements during the 2013 IsoCloud campaign at the AIDA cloud chamber show no evidence of this
anomalous supersaturationin conditions similar to the real atmosphere.
Naama Reicher, Carsten Budke, Lukas Eickhoff, Shira Raveh-Rubin, Ifat Kaplan-Ashiri, Thomas Koop, and Yinon Rudich
Atmos. Chem. Phys., 19, 11143–11158, https://doi.org/10.5194/acp-19-11143-2019, https://doi.org/10.5194/acp-19-11143-2019, 2019
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We characterized size-segregated airborne ice-nucleating particles (INPs) during dust storm events in the eastern Mediterranean. We found that particle size can predict its activity, and in general, larger particles are better INPs. The activity of supermicron particles dominated by desert mineral dust was similar between the different dust events regardless of the high variability of the geographic source desert and atmospheric journey.
Xianda Gong, Heike Wex, Thomas Müller, Alfred Wiedensohler, Kristina Höhler, Konrad Kandler, Nan Ma, Barbara Dietel, Thea Schiebel, Ottmar Möhler, and Frank Stratmann
Atmos. Chem. Phys., 19, 10883–10900, https://doi.org/10.5194/acp-19-10883-2019, https://doi.org/10.5194/acp-19-10883-2019, 2019
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For the diverse aerosol on Cyprus, we found the following: new particle formation can be a source of cloud condensation nuclei. Particle hygroscopicity showed that particles ~<100 nm contained mostly organic material, while larger ones were more hygroscopic. Two separate methods obtained similar concentrations of ice-nucleating particles (INP), with mostly no evidence of a local origin. Different parameterizations overestimated INP concentration in this rather polluted region.
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.
Naruki Hiranuma, Kouji Adachi, David M. Bell, Franco Belosi, Hassan Beydoun, Bhaskar Bhaduri, Heinz Bingemer, Carsten Budke, Hans-Christian Clemen, Franz Conen, Kimberly M. Cory, Joachim Curtius, Paul J. DeMott, Oliver Eppers, Sarah Grawe, Susan Hartmann, Nadine Hoffmann, Kristina Höhler, Evelyn Jantsch, Alexei Kiselev, Thomas Koop, Gourihar Kulkarni, Amelie Mayer, Masataka Murakami, Benjamin J. Murray, Alessia Nicosia, Markus D. Petters, Matteo Piazza, Michael Polen, Naama Reicher, Yinon Rudich, Atsushi Saito, Gianni Santachiara, Thea Schiebel, Gregg P. Schill, Johannes Schneider, Lior Segev, Emiliano Stopelli, Ryan C. Sullivan, Kaitlyn Suski, Miklós Szakáll, Takuya Tajiri, Hans Taylor, Yutaka Tobo, Romy Ullrich, Daniel Weber, Heike Wex, Thomas F. Whale, Craig L. Whiteside, Katsuya Yamashita, Alla Zelenyuk, and Ottmar Möhler
Atmos. Chem. Phys., 19, 4823–4849, https://doi.org/10.5194/acp-19-4823-2019, https://doi.org/10.5194/acp-19-4823-2019, 2019
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A total of 20 ice nucleation measurement techniques contributed to investigate the immersion freezing behavior of cellulose particles – natural polymers. Our data showed several types of cellulose are able to nucleate ice as efficiently as some mineral dust samples and cellulose has the potential to be an important atmospheric ice-nucleating particle. Continued investigation/collaboration is necessary to obtain further insight into consistency or diversity of ice nucleation measurements.
Nicholas A. Marsden, Romy Ullrich, Ottmar Möhler, Stine Eriksen Hammer, Konrad Kandler, Zhiqiang Cui, Paul I. Williams, Michael J. Flynn, Dantong Liu, James D. Allan, and Hugh Coe
Atmos. Chem. Phys., 19, 2259–2281, https://doi.org/10.5194/acp-19-2259-2019, https://doi.org/10.5194/acp-19-2259-2019, 2019
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The composition of airborne dust influences climate and ecosystems but its measurements presents a huge analytical challenge. Using online single-particle mass spectrometry, we demonstrate differences in mineralogy and mixing state can be detected in real time in both laboratory studies and ambient measurements. The results provide insights into the temporal and spatial evolution of dust properties that will be useful for aerosol–cloud interaction studies and dust cycle modelling.
Kaitlyn J. Suski, David M. Bell, Naruki Hiranuma, Ottmar Möhler, Dan Imre, and Alla Zelenyuk
Atmos. Chem. Phys., 18, 17497–17513, https://doi.org/10.5194/acp-18-17497-2018, https://doi.org/10.5194/acp-18-17497-2018, 2018
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This work investigates the cloud condensation nuclei and ice nucleation activity of bacteria using cloud chamber data and a single particle mass spectrometer. The size and chemical composition of the cloud residuals show that bacterial fragments mixed with agar growth media activate preferentially over intact bacteria cells as cloud condensation nuclei. Intact bacteria cells do not make it into cloud droplets; they thus cannot serve as immersion-mode ice nucleating particles.
Paul J. DeMott, Ottmar Möhler, Daniel J. Cziczo, Naruki Hiranuma, Markus D. Petters, Sarah S. Petters, Franco Belosi, Heinz G. Bingemer, Sarah D. Brooks, Carsten Budke, Monika Burkert-Kohn, Kristen N. Collier, Anja Danielczok, Oliver Eppers, Laura Felgitsch, Sarvesh Garimella, Hinrich Grothe, Paul Herenz, Thomas C. J. Hill, Kristina Höhler, Zamin A. Kanji, Alexei Kiselev, Thomas Koop, Thomas B. Kristensen, Konstantin Krüger, Gourihar Kulkarni, Ezra J. T. Levin, Benjamin J. Murray, Alessia Nicosia, Daniel O'Sullivan, Andreas Peckhaus, Michael J. Polen, Hannah C. Price, Naama Reicher, Daniel A. Rothenberg, Yinon Rudich, Gianni Santachiara, Thea Schiebel, Jann Schrod, Teresa M. Seifried, Frank Stratmann, Ryan C. Sullivan, Kaitlyn J. Suski, Miklós Szakáll, Hans P. Taylor, Romy Ullrich, Jesus Vergara-Temprado, Robert Wagner, Thomas F. Whale, Daniel Weber, André Welti, Theodore W. Wilson, Martin J. Wolf, and Jake Zenker
Atmos. Meas. Tech., 11, 6231–6257, https://doi.org/10.5194/amt-11-6231-2018, https://doi.org/10.5194/amt-11-6231-2018, 2018
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The ability to measure ice nucleating particles is vital to quantifying their role in affecting clouds and precipitation. Methods for measuring droplet freezing were compared while co-sampling relevant particle types. Measurement correspondence was very good for ice nucleating particles of bacterial and natural soil origin, and somewhat more disparate for those of mineral origin. Results reflect recently improved capabilities and provide direction toward addressing remaining measurement issues.
Jörn Lessmeier, Hans Peter Dette, Adelheid Godt, and Thomas Koop
Atmos. Chem. Phys., 18, 15841–15857, https://doi.org/10.5194/acp-18-15841-2018, https://doi.org/10.5194/acp-18-15841-2018, 2018
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We synthesized a compound, a tetraol, which is an atmospheric oxidation product in isoprene-derived secondary organic aerosols, and studied whether the tetraol is liquid or solid depending upon temperature and relative humidity, both in pure form and in mixtures with other compounds. Our results imply a liquid state of
isoprene-derived aerosol particles in the lower troposphere at moderate humidity, but a solid state at colder upper tropospheric conditions, thus supporting modeling calculations.
Matthias Hummel, Corinna Hoose, Bernhard Pummer, Caroline Schaupp, Janine Fröhlich-Nowoisky, and Ottmar Möhler
Atmos. Chem. Phys., 18, 15437–15450, https://doi.org/10.5194/acp-18-15437-2018, https://doi.org/10.5194/acp-18-15437-2018, 2018
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How important for clouds is the ability of biological particles to glaciate droplets at little supercooling? In a case study, the regional atmospheric model COSMO–ART is used. Perturbed and control runs are compared.
The number of ice particles that are nucleated by biological particles is highest at around −10 °C. No significant influence on the average state of the cloud ice phase was found. However, the number of ice crystals is slightly enhanced in the absence of other ice nucleators.
Costa D. Christopoulos, Sarvesh Garimella, Maria A. Zawadowicz, Ottmar Möhler, and Daniel J. Cziczo
Atmos. Meas. Tech., 11, 5687–5699, https://doi.org/10.5194/amt-11-5687-2018, https://doi.org/10.5194/amt-11-5687-2018, 2018
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Compositional analysis of atmospheric and laboratory aerosols is often conducted with mass spectrometry. In this study, machine learning is used to automatically differentiate particles on the basis of chemistry and size. The ability of the machine learning algorithm was then tested on a data set for which the particles were not initially known to judge its ability.
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.
Leonid Nichman, Emma Järvinen, James Dorsey, Paul Connolly, Jonathan Duplissy, Claudia Fuchs, Karoliina Ignatius, Kamalika Sengupta, Frank Stratmann, Ottmar Möhler, Martin Schnaiter, and Martin Gallagher
Atmos. Meas. Tech., 10, 3231–3248, https://doi.org/10.5194/amt-10-3231-2017, https://doi.org/10.5194/amt-10-3231-2017, 2017
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Optical probes are frequently used for the detection of cloud particles. The detected microphysical properties may affect particle growth and accretion mechanisms and the light scattering properties of cirrus clouds. In the CLOUD chamber study at CERN, we compared four optical measurement techniques. We show that shape derivation alone is not sufficient to determine the phase of the small cloud particles. None of the instruments were able to unambiguously determine the phase of small particles.
Ahmed Abdelmonem, Ellen H. G. Backus, Nadine Hoffmann, M. Alejandra Sánchez, Jenée D. Cyran, Alexei Kiselev, and Mischa Bonn
Atmos. Chem. Phys., 17, 7827–7837, https://doi.org/10.5194/acp-17-7827-2017, https://doi.org/10.5194/acp-17-7827-2017, 2017
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We report the effect of surface charge on heterogeneous immersion freezing for the atmospherically relevant sapphire surface. Combining linear and nonlinear optical techniques and investigating isolated drops, we find that charge-induced surface templating is detrimental for ice nucleation on α-alumina surface. This study provides new insights into atmospheric processes and can impact various industrial and research branches, particularly climate change and tracing of water in the hydrosphere.
Giancarlo Ciarelli, Imad El Haddad, Emily Bruns, Sebnem Aksoyoglu, Ottmar Möhler, Urs Baltensperger, and André S. H. Prévôt
Geosci. Model Dev., 10, 2303–2320, https://doi.org/10.5194/gmd-10-2303-2017, https://doi.org/10.5194/gmd-10-2303-2017, 2017
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In Europe, residential wood-burning emissions constitute one of the main anthropogenic sources of air pollution. Novel wood-burning experiments performed in a state-of-the-art smog chamber provide valuable information on the chemical properties of wood-burning emissions and the transformation in the atmosphere. In this study, these new data were used in a box model to constrain a parameterization suitable for predicting the contribution of wood burning to air pollution with large-scale models.
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.
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.
Cynthia H. Twohy, Gavin R. McMeeking, Paul J. DeMott, Christina S. McCluskey, Thomas C. J. Hill, Susannah M. Burrows, Gourihar R. Kulkarni, Meryem Tanarhte, Durga N. Kafle, and Darin W. Toohey
Atmos. Chem. Phys., 16, 8205–8225, https://doi.org/10.5194/acp-16-8205-2016, https://doi.org/10.5194/acp-16-8205-2016, 2016
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Fluorescent biological aerosol particles were measured in autumn over the continental United States at a variety of altitudes and temperatures, spanning the atmospheric boundary layer to the upper troposphere. Number concentrations of these particles generally decreased with height but were most variable at middle altitudes, above the boundary layer. This corresponds to the temperature range where biological particles may be more important than mineral dust at nucleating ice in clouds.
Sarvesh Garimella, Thomas Bjerring Kristensen, Karolina Ignatius, Andre Welti, Jens Voigtländer, Gourihar R. Kulkarni, Frank Sagan, Gregory Lee Kok, James Dorsey, Leonid Nichman, Daniel Alexander Rothenberg, Michael Rösch, Amélie Catharina Ruth Kirchgäßner, Russell Ladkin, Heike Wex, Theodore W. Wilson, Luis Antonio Ladino, Jon P. D. Abbatt, Olaf Stetzer, Ulrike Lohmann, Frank Stratmann, and Daniel James Cziczo
Atmos. Meas. Tech., 9, 2781–2795, https://doi.org/10.5194/amt-9-2781-2016, https://doi.org/10.5194/amt-9-2781-2016, 2016
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The SPectrometer for Ice Nuclei (SPIN) is a commercially available ice nuclei counter manufactured by Droplet Measurement Technologies in Boulder, CO. This study characterizes the SPIN chamber, reporting data from laboratory measurements and quantifying uncertainties. Overall, we report that the SPIN is able to reproduce previous CFDC ice nucleation measurements.
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.
D. M. Lienhard, A. J. Huisman, U. K. Krieger, Y. Rudich, C. Marcolli, B. P. Luo, D. L. Bones, J. P. Reid, A. T. Lambe, M. R. Canagaratna, P. Davidovits, T. B. Onasch, D. R. Worsnop, S. S. Steimer, T. Koop, and T. Peter
Atmos. Chem. Phys., 15, 13599–13613, https://doi.org/10.5194/acp-15-13599-2015, https://doi.org/10.5194/acp-15-13599-2015, 2015
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New data of water diffusivity in secondary organic aerosol (SOA) material and organic/inorganic model mixtures is presented over an extensive temperature range. Our data suggest that water diffusion in SOA is sufficiently fast so that it is unlikely to have significant consequences on the direct climatic effect under tropospheric conditions. Glass formation in SOA is unlikely to restrict homogeneous ice nucleation.
G. Vali, P. J. DeMott, O. Möhler, and T. F. Whale
Atmos. Chem. Phys., 15, 10263–10270, https://doi.org/10.5194/acp-15-10263-2015, https://doi.org/10.5194/acp-15-10263-2015, 2015
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Clarification is needed in the terminology used to discuss ice nucleation in the literature. Conflicting interpretations coupled with uncertainties about the details of the processes have led to difficulties in the clear communication of results and ideas. This paper contains a proposal for future usage. This proposed terminology was arrived at as a result of a year-long exchange of suggestions by a number of scientists.
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
P. Amato, M. Joly, C. Schaupp, E. Attard, O. Möhler, C. E. Morris, Y. Brunet, and A.-M. Delort
Atmos. Chem. Phys., 15, 6455–6465, https://doi.org/10.5194/acp-15-6455-2015, https://doi.org/10.5194/acp-15-6455-2015, 2015
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Mortality rate of typical bacterial aerosols (Pseudomonas species) was determined in a cloud simulation chamber. Ice nucleation activity remained unchanged for several hours in aerosolized cells, whether they were viable or not. Cloud increased the specific removal of ice nucleation active cells by precipitation. Survival was negatively impacted by the presence of cloud and by sulfates.
B. G. Pummer, C. Budke, S. Augustin-Bauditz, D. Niedermeier, L. Felgitsch, C. J. Kampf, R. G. Huber, K. R. Liedl, T. Loerting, T. Moschen, M. Schauperl, M. Tollinger, C. E. Morris, H. Wex, H. Grothe, U. Pöschl, T. Koop, and J. Fröhlich-Nowoisky
Atmos. Chem. Phys., 15, 4077–4091, https://doi.org/10.5194/acp-15-4077-2015, https://doi.org/10.5194/acp-15-4077-2015, 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.
H. Wex, S. Augustin-Bauditz, Y. Boose, C. Budke, J. Curtius, K. Diehl, A. Dreyer, F. Frank, S. Hartmann, N. Hiranuma, E. Jantsch, Z. A. Kanji, A. Kiselev, T. Koop, O. Möhler, D. Niedermeier, B. Nillius, M. Rösch, D. Rose, C. Schmidt, I. Steinke, and F. Stratmann
Atmos. Chem. Phys., 15, 1463–1485, https://doi.org/10.5194/acp-15-1463-2015, https://doi.org/10.5194/acp-15-1463-2015, 2015
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Immersion freezing measurements from seven different measurement techniques were intercompared using a biological ice nucleating material from bacteria. Although different techniques examined differently concentrated droplets, it was possible to find a uniform description, which showed that results from all experiments were generally in good agreement and were also in agreement with parameterizations published earlier in literature.
C. Budke and T. Koop
Atmos. Meas. Tech., 8, 689–703, https://doi.org/10.5194/amt-8-689-2015, https://doi.org/10.5194/amt-8-689-2015, 2015
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A new optical freezing array for the study of heterogeneous ice nucleation in microliter-sized droplets is introduced, tested and applied to the study of immersion freezing in aqueous Snomax suspensions. Using different cooling rates, a small time dependence of ice nucleation induced by two different classes of ice nucleators was detected and the corresponding heterogeneous ice nucleation rate coefficient was quantified.
P. J. DeMott, A. J. Prenni, G. R. McMeeking, R. C. Sullivan, M. D. Petters, Y. Tobo, M. Niemand, O. Möhler, J. R. Snider, Z. Wang, and S. M. Kreidenweis
Atmos. Chem. Phys., 15, 393–409, https://doi.org/10.5194/acp-15-393-2015, https://doi.org/10.5194/acp-15-393-2015, 2015
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Laboratory and field data are used together to develop an empirical relation between the concentrations of mineral dust particles at sizes above 0.5 microns, approximated as a single compositional type, and ice nucleating particle concentrations measured versus temperature. This should be useful in global modeling of ice cloud formation. The utility of laboratory data for parameterization development is reinforced, and the need for careful interpretation of ice nucleation data is emphasized.
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.
T. Berkemeier, M. Shiraiwa, U. Pöschl, and T. Koop
Atmos. Chem. Phys., 14, 12513–12531, https://doi.org/10.5194/acp-14-12513-2014, https://doi.org/10.5194/acp-14-12513-2014, 2014
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Glassy organic particles can serve as ice nuclei at low temperatures. We provide a rationale for these findings using a numerical aerosol diffusion model that describes particle phase state and its kinetics during simulated atmospheric updrafts dependent upon composition, size, updraft velocity, temperature and humidity. Our simulations suggest that aerosols from anthropogenic aromatic organics can be particularly relevant for ice cloud formation.
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
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
H. Wan, P. J. Rasch, K. Zhang, Y. Qian, H. Yan, and C. Zhao
Geosci. Model Dev., 7, 1961–1977, https://doi.org/10.5194/gmd-7-1961-2014, https://doi.org/10.5194/gmd-7-1961-2014, 2014
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
S. M. Platt, I. El Haddad, A. A. Zardini, M. Clairotte, C. Astorga, R. Wolf, J. G. Slowik, B. Temime-Roussel, N. Marchand, I. Ježek, L. Drinovec, G. Močnik, O. Möhler, R. Richter, P. Barmet, F. Bianchi, U. Baltensperger, and A. S. H. Prévôt
Atmos. Chem. Phys., 13, 9141–9158, https://doi.org/10.5194/acp-13-9141-2013, https://doi.org/10.5194/acp-13-9141-2013, 2013
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
T. Berkemeier, A. J. Huisman, M. Ammann, M. Shiraiwa, T. Koop, and U. Pöschl
Atmos. Chem. Phys., 13, 6663–6686, https://doi.org/10.5194/acp-13-6663-2013, https://doi.org/10.5194/acp-13-6663-2013, 2013
H. Wan, P. J. Rasch, K. Zhang, J. Kazil, and L. R. Leung
Geosci. Model Dev., 6, 861–874, https://doi.org/10.5194/gmd-6-861-2013, https://doi.org/10.5194/gmd-6-861-2013, 2013
K. Zhang, X. Liu, M. Wang, J. M. Comstock, D. L. Mitchell, S. Mishra, and G. G. Mace
Atmos. Chem. Phys., 13, 4963–4982, https://doi.org/10.5194/acp-13-4963-2013, https://doi.org/10.5194/acp-13-4963-2013, 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: Laboratory Studies | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Viscosity of aqueous ammonium nitrate–organic particles: Equilibrium partitioning may be a reasonable assumption for most tropospheric conditions
Role of sea spray aerosol at the air–sea interface in transporting aromatic acids to the atmosphere
Modeling the influence of carbon branching structure on secondary organic aerosol formation via multiphase reactions of alkanes
Technical note: Characterization of a single-beam gradient force aerosol optical tweezer for droplet trapping, phase transition monitoring, and morphology studies
Soot aerosols from commercial aviation engines are poor ice-nucleating particles at cirrus cloud temperatures
Contribution of brown carbon to light absorption in emissions of European residential biomass combustion appliances
Measurement report: Water diffusion in single suspended phase-separated aerosols
Water activity and surface tension of aqueous ammonium sulfate and D-glucose aerosol nanoparticles
Jet aircraft lubrication oil droplets as contrail ice-forming particles
A study on the influence of inorganic ions, organic carbon and microstructure on the hygroscopic property of soot
Measurement report: The ice-nucleating activity of lichen sampled in a northern European boreal forest
Is transport of microplastics different from mineral particles? Idealized wind tunnel studies on polyethylene microspheres
Insights into secondary organic aerosol formation from the day- and nighttime oxidation of polycyclic aromatic hydrocarbons and furans in an oxidation flow reactor
Analysis of insoluble particles in hailstones in China
Influence of acidity on liquid–liquid phase transitions of mixed secondary organic aerosol (SOA) proxy–inorganic aerosol droplets
Deposition freezing, pore condensation freezing and adsorption: three processes, one description?
Measurements and calculations of enhanced side- and back-scattering of visible radiation by black carbon aggregates
Direct observation for relative-humidity-dependent mixing states of submicron particles containing organic surfactants and inorganic salts
Complex refractive index and single scattering albedo of Icelandic dust in the shortwave part of the spectrum
Volatility of aerosol particles from NO3 oxidation of various biogenic organic precursors
Saturation vapor pressure characterization of selected low-volatility organic compounds using a residence time chamber
Influence of the previous North Atlantic Oscillation (NAO) on the spring dust aerosols over North China
HUB: a method to model and extract the distribution of ice nucleation temperatures from drop-freezing experiments
Size-dependent hygroscopicity of levoglucosan and D-glucose aerosol nanoparticles
Technical note: Sublimation of frozen CsCl solutions in an environmental scanning electron microscope (ESEM) – determining the number and size of salt particles relevant to sea salt aerosols
Microphysics of liquid water in sub-10 nm ultrafine aerosol particles
Comparing the ice nucleation properties of the kaolin minerals kaolinite and halloysite
Physicochemical properties of charcoal aerosols derived from biomass pyrolysis affect their ice-nucleating abilities at cirrus and mixed-phase cloud conditions
Reconsideration of surface tension and phase state effects on cloud condensation nuclei activity based on the atomic force microscopy measurement
Hygroscopicity and CCN potential of DMS-derived aerosol particles
Hybrid water adsorption and solubility partitioning for aerosol hygroscopicity and droplet growth
Experimental development of a lake spray source function and its model implementation for Great Lakes surface emissions
The effectiveness of the coagulation sink of 3–10 nm atmospheric particles
What caused the interdecadal shift in the El Niño–Southern Oscillation (ENSO) impact on dust mass concentration over northwestern South Asia?
Measurement report: An exploratory study of fluorescence and cloud condensation nuclei activity of urban aerosols in San Juan, Puerto Rico
Viscosity and physical state of sucrose mixed with ammonium sulfate droplets
Distribution and stable carbon isotopic composition of dicarboxylic acids, ketocarboxylic acids and α-dicarbonyls in fresh and aged biomass burning aerosols
Time dependence of heterogeneous ice nucleation by ambient aerosols: laboratory observations and a formulation for models
Laboratory studies of ice nucleation onto bare and internally mixed soot–sulfuric acid particles
Enhanced soot particle ice nucleation ability induced by aggregate compaction and densification
Opinion: Insights into updating Ambient Air Quality Directive 2008/50/EC
On the evolution of sub- and super-saturated water uptake of secondary organic aerosol in chamber experiments from mixed precursors
Hygroscopicity of organic compounds as a function of organic functionality, water solubility, molecular weight, and oxidation level
Particle emissions from a modern heavy-duty diesel engine as ice nuclei in immersion freezing mode: a laboratory study on fossil and renewable fuels
Comparison of saturation vapor pressures of α-pinene + O3 oxidation products derived from COSMO-RS computations and thermal desorption experiments
Physical and chemical properties of black carbon and organic matter from different combustion and photochemical sources using aerodynamic aerosol classification
Technical note: Pyrolysis principles explain time-resolved organic aerosol release from biomass burning
The effect of (NH4)2SO4 on the freezing properties of non-mineral dust ice-nucleating substances of atmospheric relevance
Heterogeneous ice nucleation ability of aerosol particles generated from Arctic sea surface microlayer and surface seawater samples at cirrus temperatures
Aerosol formation and growth rates from chamber experiments using Kalman smoothing
Liviana K. Klein, Allan K. Bertram, Andreas Zuend, Florence Gregson, and Ulrich K. Krieger
EGUsphere, https://doi.org/10.5194/egusphere-2024-1459, https://doi.org/10.5194/egusphere-2024-1459, 2024
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The viscosity of ammonium nitrate–sucrose–H2O was quantified with three methods ranging from liquid to solid state depending on the relative humidity. Moreover, the corresponding estimated internal aerosol mixing times remain below an hour for most tropospheric conditions, making equilibrium partitioning a reasonable assumption.
Yaru Song, Jianlong Li, Narcisse Tsona Tchinda, Kun Li, and Lin Du
Atmos. Chem. Phys., 24, 5847–5862, https://doi.org/10.5194/acp-24-5847-2024, https://doi.org/10.5194/acp-24-5847-2024, 2024
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Aromatic acids can be transferred from seawater to the atmosphere through bubble bursting. The air–sea transfer efficiency of aromatic acids was evaluated by simulating SSA generation with a plunging jet. As a whole, the transfer capacity of aromatic acids may depend on their functional groups and on the bridging effect of cations, as well as their concentration in seawater, as these factors influence the global emission flux of aromatic acids via SSA.
Azad Madhu, Myoseon Jang, and Yujin Jo
Atmos. Chem. Phys., 24, 5585–5602, https://doi.org/10.5194/acp-24-5585-2024, https://doi.org/10.5194/acp-24-5585-2024, 2024
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Secondary organic aerosol (SOA) formation from branched alkanes (BAs) was simulated using the UNIPAR model, which predicted SOA growth via multiphase reactions of hydrocarbons, and compared with chamber data. Product distributions (PDs) of BAs were created by extrapolating PDs of linear alkanes (LAs). To account for methyl branching, an autoxidation reduction factor was applied to PDs. BAs in diesel fuel were shown to produce a higher proportion of SOA compared with LAs.
Xiangyu Pei, Yikan Meng, Yueling Chen, Huichao Liu, Yao Song, Zhengning Xu, Fei Zhang, Thomas C. Preston, and Zhibin Wang
Atmos. Chem. Phys., 24, 5235–5246, https://doi.org/10.5194/acp-24-5235-2024, https://doi.org/10.5194/acp-24-5235-2024, 2024
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An aerosol optical tweezer (AOT) Raman spectroscopy system is developed to capture a single aerosol droplet for phase transition monitoring and morphology studies. Rapid droplet capture is achieved and accurate droplet size and refractive index are retrieved. Results indicate that mixed inorganic/organic droplets are more inclined to form core–shell morphology when RH decreases. The phase transitions of secondary mixed organic aerosol/inorganic droplets vary with their precursors.
Baptiste Testa, Lukas Durdina, Peter A. Alpert, Fabian Mahrt, Christopher H. Dreimol, Jacinta Edebeli, Curdin Spirig, Zachary C. J. Decker, Julien Anet, and Zamin A. Kanji
Atmos. Chem. Phys., 24, 4537–4567, https://doi.org/10.5194/acp-24-4537-2024, https://doi.org/10.5194/acp-24-4537-2024, 2024
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Laboratory experiments on the ice nucleation of real commercial aviation soot particles are investigated for their cirrus cloud formation potential. Our results show that aircraft-emitted soot in the upper troposphere will be poor ice-nucleating particles. Measuring the soot particle morphology and modifying their mixing state allow us to elucidate why these particles are ineffective at forming ice, in contrast to previously used soot surrogates.
Satish Basnet, Anni Hartikainen, Aki Virkkula, Pasi Yli-Pirilä, Miika Kortelainen, Heikki Suhonen, Laura Kilpeläinen, Mika Ihalainen, Sampsa Väätäinen, Juho Louhisalmi, Markus Somero, Jarkko Tissari, Gert Jakobi, Ralf Zimmermann, Antti Kilpeläinen, and Olli Sippula
Atmos. Chem. Phys., 24, 3197–3215, https://doi.org/10.5194/acp-24-3197-2024, https://doi.org/10.5194/acp-24-3197-2024, 2024
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Brown carbon (BrC) emissions were estimated, for residential wood combustion (RWC) from various northern European appliances, utilizing an extensive seven-wavelength aethalometer dataset and thermal–optical carbon analysis. The contribution of BrC370–950 to the absorption of visible light varied between 1 % and 21 %, and was linked with fuel moisture content and combustion efficiency. This study provides important information required for assessing the climate effects of RWC emissions.
Yu-Kai Tong, Zhijun Wu, Min Hu, and Anpei Ye
Atmos. Chem. Phys., 24, 2937–2950, https://doi.org/10.5194/acp-24-2937-2024, https://doi.org/10.5194/acp-24-2937-2024, 2024
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The interplay between aerosols and moisture is one of the most crucial atmospheric processes. However, to date, literature results on the influence of phase separation on water diffusion in aerosols are divergent. This work directly unveiled the water diffusion process in single suspended phase-separated microdroplets and quantitatively analyzed the diffusion rate and extent. The results show that diffusion limitations and certain molecule clusters existed in the phase-separated aerosols.
Eugene F. Mikhailov, Sergey S. Vlasenko, and Alexei A. Kiselev
Atmos. Chem. Phys., 24, 2971–2984, https://doi.org/10.5194/acp-24-2971-2024, https://doi.org/10.5194/acp-24-2971-2024, 2024
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Surface tension and water activity are key thermodynamic parameters determining the impact of atmospheric aerosols on human health and climate. However, these parameters are not well constrained for nanoparticles composed of organic and inorganic compounds. In this study, we determined for the first time the water activity and surface tension of mixed organic/inorganic nanodroplets by applying a differential Köhler analysis (DKA) to hygroscopic growth measurements.
Joel Ponsonby, Leon King, Benjamin J. Murray, and Marc E. J. Stettler
Atmos. Chem. Phys., 24, 2045–2058, https://doi.org/10.5194/acp-24-2045-2024, https://doi.org/10.5194/acp-24-2045-2024, 2024
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Aerosol emissions from aircraft engines contribute to the formation of contrails, which have a climate impact as important as that of aviation’s CO2 emissions. For the first time, we experimentally investigate the freezing behaviour of water droplets formed on jet lubrication oil aerosol. We show that they can activate to form water droplets and discuss their potential impact on contrail formation. Our study has implications for contrails produced by future aircraft engine and fuel technologies.
Zhanyu Su, Lanxiadi Chen, Yuan Liu, Peng Zhang, Tianzeng Chen, Biwu Chu, Mingjin Tang, Qingxin Ma, and Hong He
Atmos. Chem. Phys., 24, 993–1003, https://doi.org/10.5194/acp-24-993-2024, https://doi.org/10.5194/acp-24-993-2024, 2024
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In this study, different soot particles were analyzed to better understand their behavior. It was discovered that water-soluble substances in soot facilitate water adsorption at low humidity while increasing the number of water layers at high humidity. Soot from organic fuels exhibits hygroscopicity influenced by organic carbon and microstructure. Additionally, the presence of sulfate ions due to the oxidation of SO2 enhances soot's hygroscopicity.
Ulrike Proske, Michael P. Adams, Grace C. E. Porter, Mark Holden, Jaana Bäck, and Benjamin J. Murray
EGUsphere, https://doi.org/10.5194/egusphere-2023-2780, https://doi.org/10.5194/egusphere-2023-2780, 2024
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Ice nucleating particles aid freezing of water droplets in clouds and thus modify clouds' properties. During a campaign in the boreal forest in Finland, substantial concentrations of biological ice nucleating particles were observed, despite many of their potential biological sources being snow covered. We sampled lichen in this location and tested its ice nculeation ability in the laboratory. We find that indeed the lichen harbours INPs, which may be important in such snow covered environments.
Eike Maximilian Esders, Sebastian Sittl, Inka Krammel, Wolfgang Babel, Georg Papastavrou, and Christoph Karl Thomas
Atmos. Chem. Phys., 23, 15835–15851, https://doi.org/10.5194/acp-23-15835-2023, https://doi.org/10.5194/acp-23-15835-2023, 2023
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Do microplastics behave differently from mineral particles when they are exposed to wind? We observed plastic and mineral particles in a wind tunnel and measured at what wind speeds the particles start to move. The results indicate that microplastics start to move at smaller wind speeds as they weigh less and are less sticky. Hence, we think that microplastics also move more easily in the environment.
Abd El Rahman El Mais, Barbara D'Anna, Luka Drinovec, Andrew T. Lambe, Zhe Peng, Jean-Eudes Petit, Olivier Favez, Selim Aït-Aïssa, and Alexandre Albinet
Atmos. Chem. Phys., 23, 15077–15096, https://doi.org/10.5194/acp-23-15077-2023, https://doi.org/10.5194/acp-23-15077-2023, 2023
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Polycyclic aromatic hydrocarbons (PAHS) and furans are key precursors of secondary organic aerosols (SOAs) related to biomass burning emissions. We evaluated and compared the formation yields, and the physical and light absorption properties, of laboratory-generated SOAs from the oxidation of such compounds for both, day- and nighttime reactivities. The results illustrate that PAHs are large SOA precursors and may contribute significantly to the biomass burning brown carbon in the atmosphere.
Haifan Zhang, Xiangyu Lin, Qinghong Zhang, Kai Bi, Chan-Pang Ng, Yangze Ren, Huiwen Xue, Li Chen, and Zhuolin Chang
Atmos. Chem. Phys., 23, 13957–13971, https://doi.org/10.5194/acp-23-13957-2023, https://doi.org/10.5194/acp-23-13957-2023, 2023
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This work is the first study to simultaneously analyze the number concentrations and species of insoluble particles in hailstones. The size distribution of insoluble particles for each species vary greatly in different hailstorms but little in shells. Two classic size distribution modes of organics and dust were fitted for the description of insoluble particles in deep convection. Combining this study with future experiments will lead to refinement of weather and climate models.
Yueling Chen, Xiangyu Pei, Huichao Liu, Yikan Meng, Zhengning Xu, Fei Zhang, Chun Xiong, Thomas C. Preston, and Zhibin Wang
Atmos. Chem. Phys., 23, 10255–10265, https://doi.org/10.5194/acp-23-10255-2023, https://doi.org/10.5194/acp-23-10255-2023, 2023
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The impact of acidity on the phase transition behavior of levitated aerosol particles was examined. Our results revealed that lower acidity decreases the separation relative humidity of aerosol droplets mixed with ammonium sulfate and secondary organic aerosol proxy. Our research suggests that in real atmospheric conditions, with the high acidity found in many ambient aerosol particles, droplets encounter heightened impediments to phase separation and tend to display a homogeneous structure.
Mária Lbadaoui-Darvas, Ari Laaksonen, and Athanasios Nenes
Atmos. Chem. Phys., 23, 10057–10074, https://doi.org/10.5194/acp-23-10057-2023, https://doi.org/10.5194/acp-23-10057-2023, 2023
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Heterogeneous ice nucleation is the main ice formation mechanism in clouds. The mechanism of different freezing modes is to date unknown, which results in large model biases. Experiments do not allow for direct observation of ice nucleation at its native resolution. This work uses first principles molecular simulations to determine the mechanism of the least-understood ice nucleation mode and link it to adsorption through a novel modeling framework that unites ice and droplet formation.
Carynelisa Haspel, Cuiqi Zhang, Martin J. Wolf, Daniel J. Cziczo, and Maor Sela
Atmos. Chem. Phys., 23, 10091–10115, https://doi.org/10.5194/acp-23-10091-2023, https://doi.org/10.5194/acp-23-10091-2023, 2023
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Small particles, commonly termed aerosols, can be found throughout the atmosphere and come from both natural and anthropogenic sources. One important type of aerosol is black carbon (BC). In this study, we conducted laboratory measurements of light scattering by particles meant to mimic atmospheric BC and compared them to calculations of scattering. We find that it is likely that calculations underpredict the scattering by BC particles of certain polarizations of light in certain directions.
Chun Xiong, Binyu Kuang, Fei Zhang, Xiangyu Pei, Zhengning Xu, and Zhibin Wang
Atmos. Chem. Phys., 23, 8979–8991, https://doi.org/10.5194/acp-23-8979-2023, https://doi.org/10.5194/acp-23-8979-2023, 2023
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In hydration, an apparent water diffusion hindrance by an organic surfactant shell was confirmed, raising the inorganic deliquescence relative humidity (RH) to a nearly saturated condition. In dehydration, phase separations were observed for inorganic surfactant systems, showing a strong dependence on the organic molecular
oxygen-to-carbon ratio. Our results could improve fundamental knowledge about aerosol mixing states and decrease uncertainty in model estimations of global radiative effects.
Clarissa Baldo, Paola Formenti, Claudia Di Biagio, Gongda Lu, Congbo Song, Mathieu Cazaunau, Edouard Pangui, Jean-Francois Doussin, Pavla Dagsson-Waldhauserova, Olafur Arnalds, David Beddows, A. Robert MacKenzie, and Zongbo Shi
Atmos. Chem. Phys., 23, 7975–8000, https://doi.org/10.5194/acp-23-7975-2023, https://doi.org/10.5194/acp-23-7975-2023, 2023
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This paper presents new shortwave spectral complex refractive index and single scattering albedo data for Icelandic dust. Our results show that the imaginary part of the complex refractive index of Icelandic dust is at the upper end of the range of low-latitude dust. Furthermore, we observed that Icelandic dust is more absorbing towards the near-infrared, which we attribute to its high magnetite content. These findings are important for modeling dust aerosol radiative effects in the Arctic.
Emelie L. Graham, Cheng Wu, David M. Bell, Amelie Bertrand, Sophie L. Haslett, Urs Baltensperger, Imad El Haddad, Radovan Krejci, Ilona Riipinen, and Claudia Mohr
Atmos. Chem. Phys., 23, 7347–7362, https://doi.org/10.5194/acp-23-7347-2023, https://doi.org/10.5194/acp-23-7347-2023, 2023
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The volatility of an aerosol particle is an important parameter for describing its atmospheric lifetime. We studied the volatility of secondary organic aerosols from nitrate-initiated oxidation of three biogenic precursors with experimental methods and model simulations. We saw higher volatility than for the corresponding ozone system, and our simulations produced variable results with different parameterizations which warrant a re-evaluation of the treatment of the nitrate functional group.
Zijun Li, Noora Hyttinen, Miika Vainikka, Olli-Pekka Tikkasalo, Siegfried Schobesberger, and Taina Yli-Juuti
Atmos. Chem. Phys., 23, 6863–6877, https://doi.org/10.5194/acp-23-6863-2023, https://doi.org/10.5194/acp-23-6863-2023, 2023
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The saturation vapor pressure (psat) of low-volatility organic compounds (LVOCs) governs their partitioning between the gas and particle phases. To estimate the psat of selected LVOCs, we performed particle evaporation measurements in a residence time chamber at a temperature setting relevant to atmospheric aerosol formation and conducted state-of-the-art computational calculations. We found good agreement between the experimentally measured and model-estimated psat values for most LVOCs.
Yan Li, Falei Xu, Juan Feng, Mengying Du, Wenjun Song, Chao Li, and Wenjing Zhao
Atmos. Chem. Phys., 23, 6021–6042, https://doi.org/10.5194/acp-23-6021-2023, https://doi.org/10.5194/acp-23-6021-2023, 2023
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There is a significantly negative relationship between boreal winter North Atlantic Oscillation (NAO) and dust aerosols (DAs) in the eastern part of China (30–40°N, 105–120°E), which is not a DA source area but is severely affected by the dust events (DEs). Under the effect of the NAO negative phase, main atmospheric circulation during the DEs is characterized by variation of the transient eddy flux. The work is of reference value to the prediction of DEs and the understanding of their causes.
Ingrid de Almeida Ribeiro, Konrad Meister, and Valeria Molinero
Atmos. Chem. Phys., 23, 5623–5639, https://doi.org/10.5194/acp-23-5623-2023, https://doi.org/10.5194/acp-23-5623-2023, 2023
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Ice formation is a key atmospheric process facilitated by a wide range of aerosols. We present a method to model and interpret ice nucleation experiments and extract the distribution of the potency of nucleation sites. We use the method to optimize the conditions of laboratory sampling and extract distributions of ice nucleation temperatures from bacteria, fungi, and pollen. These reveal unforeseen subpopulations of nuclei in these systems and how they respond to changes in their environment.
Ting Lei, Hang Su, Nan Ma, Ulrich Pöschl, Alfred Wiedensohler, and Yafang Cheng
Atmos. Chem. Phys., 23, 4763–4774, https://doi.org/10.5194/acp-23-4763-2023, https://doi.org/10.5194/acp-23-4763-2023, 2023
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We investigate the hygroscopic behavior of levoglucosan and D-glucose nanoparticles using a nano-HTDMA. There is a weak size dependence of the hygroscopic growth factor of levoglucosan and D-glucose with diameters down to 20 nm, while a strong size dependence of the hygroscopic growth factor of D-glucose has been clearly observed in the size range 6 to 20 nm. The use of the DKA method leads to good agreement with the hygroscopic growth factor of glucose nanoparticles with diameters down to 6 nm.
Lubica Vetráková, Vilém Neděla, Kamila Závacká, Xin Yang, and Dominik Heger
Atmos. Chem. Phys., 23, 4463–4488, https://doi.org/10.5194/acp-23-4463-2023, https://doi.org/10.5194/acp-23-4463-2023, 2023
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Salt aerosols are important to polar atmospheric chemistry and global climate. Therefore, we utilized a unique electron microscope to identify the most suitable conditions for formation of the small salt (CsCl) particles, proxies of the aerosols, from sublimating salty snow. Very low sublimation temperature and low salt concentration are needed for formation of such particles. These observations may help us to better understand polar spring ozone depletion and bromine explosion events.
Xiaohan Li and Ian C. Bourg
Atmos. Chem. Phys., 23, 2525–2556, https://doi.org/10.5194/acp-23-2525-2023, https://doi.org/10.5194/acp-23-2525-2023, 2023
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Aerosol particles with sizes smaller than 50 nm impact cloud formation and precipitation. Representation of this effect is hindered by limited understanding of the properties of liquid water in these particles. Our simulations of aerosol particles containing salt or organic compounds reveal that water enters a less cohesive phase at droplet sizes below 4 nm. This effect causes important deviations from theoretical predictions of aerosol properties, including phase state and hygroscopic growth.
Kristian Klumpp, Claudia Marcolli, Ana Alonso-Hellweg, Christopher H. Dreimol, and Thomas Peter
Atmos. Chem. Phys., 23, 1579–1598, https://doi.org/10.5194/acp-23-1579-2023, https://doi.org/10.5194/acp-23-1579-2023, 2023
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The prerequisites of a particle surface for efficient ice nucleation are still poorly understood. This study compares the ice nucleation activity of two chemically identical but morphologically different minerals (kaolinite and halloysite). We observe, on average, not only higher ice nucleation activities for halloysite than kaolinite but also higher diversity between individual samples. We identify the particle edges as being the most likely site for ice nucleation.
Fabian Mahrt, Carolin Rösch, Kunfeng Gao, Christopher H. Dreimol, Maria A. Zawadowicz, and Zamin A. Kanji
Atmos. Chem. Phys., 23, 1285–1308, https://doi.org/10.5194/acp-23-1285-2023, https://doi.org/10.5194/acp-23-1285-2023, 2023
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Major aerosol types emitted by biomass burning include soot, ash, and charcoal particles. Here, we investigated the ice nucleation activity of 400 nm size-selected particles of two different pyrolyis-derived charcoal types in the mixed phase and cirrus cloud regime. We find that ice nucleation is constrained to cirrus cloud conditions, takes place via pore condensation and freezing, and is largely governed by the particle porosity and mineral content.
Chun Xiong, Xueyan Chen, Xiaolei Ding, Binyu Kuang, Xiangyu Pei, Zhengning Xu, Shikuan Yang, Huan Hu, and Zhibin Wang
Atmos. Chem. Phys., 22, 16123–16135, https://doi.org/10.5194/acp-22-16123-2022, https://doi.org/10.5194/acp-22-16123-2022, 2022
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Water surface tension is applied widely in current aerosol–cloud models but could be inappropriate in the presence of atmospheric surfactants. With cloud condensation nuclei (CCN) activity and atomic force microscopy (AFM) measurement results of mixed inorganic salt and dicarboxylic acid particles, we concluded that surface tension reduction and phase state should be carefully considered in aerosol–cloud interactions. Our results could help to decease uncertainties in climate models.
Bernadette Rosati, Sini Isokääntä, Sigurd Christiansen, Mads Mørk Jensen, Shamjad P. Moosakutty, Robin Wollesen de Jonge, Andreas Massling, Marianne Glasius, Jonas Elm, Annele Virtanen, and Merete Bilde
Atmos. Chem. Phys., 22, 13449–13466, https://doi.org/10.5194/acp-22-13449-2022, https://doi.org/10.5194/acp-22-13449-2022, 2022
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Sulfate aerosols have a strong influence on climate. Due to the reduction in sulfur-based fossil fuels, natural sulfur emissions play an increasingly important role. Studies investigating the climate relevance of natural sulfur aerosols are scarce. We study the water uptake of such particles in the laboratory, demonstrating a high potential to take up water and form cloud droplets. During atmospheric transit, chemical processing affects the particles’ composition and thus their water uptake.
Kanishk Gohil, Chun-Ning Mao, Dewansh Rastogi, Chao Peng, Mingjin Tang, and Akua Asa-Awuku
Atmos. Chem. Phys., 22, 12769–12787, https://doi.org/10.5194/acp-22-12769-2022, https://doi.org/10.5194/acp-22-12769-2022, 2022
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The Hybrid Activity Model (HAM) is a promising new droplet growth model that can be potentially used for the analysis of any type of atmospheric compound. HAM may potentially improve the representation of hygroscopicity of organic aerosols in large-scale global climate models (GCMs), hence reducing the uncertainties in the climate forcing due to the aerosol indirect effect.
Charbel Harb and Hosein Foroutan
Atmos. Chem. Phys., 22, 11759–11779, https://doi.org/10.5194/acp-22-11759-2022, https://doi.org/10.5194/acp-22-11759-2022, 2022
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A model representation of lake spray aerosol (LSA) ejection from freshwater breaking waves is crucial for understanding their climatic and public health impacts. We develop an LSA emission parameterization and implement it in an atmospheric model to investigate Great Lakes surface emissions. We find that the same breaking wave is likely to produce fewer aerosols in freshwater than in saltwater and that Great Lakes emissions influence the regional aerosol burden and can reach the cloud layer.
Runlong Cai, Ella Häkkinen, Chao Yan, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 11529–11541, https://doi.org/10.5194/acp-22-11529-2022, https://doi.org/10.5194/acp-22-11529-2022, 2022
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The influences of new particle formation on the climate and air quality are governed by particle survival, which has been under debate due to uncertainties in the coagulation sink. Here we measure the coagulation coefficient of sub-10 nm particles and demonstrate that collisions between the freshly nucleated and background particles can effectively lead to coagulation. We further show that the effective coagulation sink is consistent with the new particle formation measured in urban Beijing.
Lamei Shi, Jiahua Zhang, Da Zhang, Jingwen Wang, Xianglei Meng, Yuqin Liu, and Fengmei Yao
Atmos. Chem. Phys., 22, 11255–11274, https://doi.org/10.5194/acp-22-11255-2022, https://doi.org/10.5194/acp-22-11255-2022, 2022
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Dust impacts climate and human life. Analyzing the interdecadal change in dust activity and its influence factors is crucial for disaster mitigation. Based on a linear regression method, this study revealed the interdecadal variability of relationships between ENSO and dust over northwestern South Asia from 1982 to 2014 and analyzed the effects of atmospheric factors on this interdecadal variability. The result sheds new light on numerical simulation involving the interdecadal variation of dust.
Bighnaraj Sarangi, Darrel Baumgardner, Benjamin Bolaños-Rosero, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 22, 9647–9661, https://doi.org/10.5194/acp-22-9647-2022, https://doi.org/10.5194/acp-22-9647-2022, 2022
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Here, the fluorescent characteristics and cloud-forming efficiency of aerosols at an urban site in Puerto Rico are discussed. The results from this pilot study highlight the capabilities of ultraviolet-induced fluorescence (UV-IF) measurements for characterizing the properties of fluorescing aerosol particles, as they relate to the daily evolution of primary biological aerosol particles. This work has established a database of measurements on which future, longer-term studies will be initiated.
Rani Jeong, Joseph Lilek, Andreas Zuend, Rongshuang Xu, Man Nin Chan, Dohyun Kim, Hi Gyu Moon, and Mijung Song
Atmos. Chem. Phys., 22, 8805–8817, https://doi.org/10.5194/acp-22-8805-2022, https://doi.org/10.5194/acp-22-8805-2022, 2022
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In this study, the viscosities of particles of sucrose–H2O, AS–H2O, and sucrose–AS–H2O for OIRs of 4:1, 1:1, and 1:4 for decreasing RH, were quantified by poke-and-flow and bead-mobility techniques at 293 ± 1 K. Based on the viscosity results, the particles of binary and ternary systems ranged from liquid to semisolid, and even the solid state depending on the RH. Moreover, we compared the measured viscosities of ternary systems to the predicted viscosities with excellent agreement.
Minxia Shen, Kin Fai Ho, Wenting Dai, Suixin Liu, Ting Zhang, Qiyuan Wang, Jingjing Meng, Judith C. Chow, John G. Watson, Junji Cao, and Jianjun Li
Atmos. Chem. Phys., 22, 7489–7504, https://doi.org/10.5194/acp-22-7489-2022, https://doi.org/10.5194/acp-22-7489-2022, 2022
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Looking at characteristics and δ13C compositions of dicarboxylic acids and related compounds in BB aerosols, we used a combined combustion and aging system to generate fresh and aged aerosols from burning straw. The results showed the emission factors (EFaged) of total diacids of aging experiments were around an order of magnitude higher than EFfresh. This meant that dicarboxylic acids are involved with secondary photochemical processes in the atmosphere rather than primary emissions from BB.
Jonas K. F. Jakobsson, Deepak B. Waman, Vaughan T. J. Phillips, and Thomas Bjerring Kristensen
Atmos. Chem. Phys., 22, 6717–6748, https://doi.org/10.5194/acp-22-6717-2022, https://doi.org/10.5194/acp-22-6717-2022, 2022
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Long-lived cold-layer clouds at subzero temperatures are observed to be remarkably persistent in their generation of ice particles and snow precipitation. There is uncertainty about why this is so. This motivates the present lab study to observe the long-term ice-nucleating ability of aerosol samples from the real troposphere. Time dependence of their ice nucleation is observed to be weak in lab experiments exposing the samples to isothermal conditions for up to about 10 h.
Kunfeng Gao, Chong-Wen Zhou, Eszter J. Barthazy Meier, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 5331–5364, https://doi.org/10.5194/acp-22-5331-2022, https://doi.org/10.5194/acp-22-5331-2022, 2022
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Incomplete combustion of fossil fuel produces carbonaceous particles called soot. These particles can affect cloud formation by acting as centres for droplet or ice formation. The atmospheric residence time of soot particles is of the order of days to weeks, which can result in them becoming coated by various trace species in the atmosphere such as acids. In this study, we quantify the cirrus cloud-forming ability of soot particles coated with the atmospherically ubiquitous sulfuric acid.
Kunfeng Gao, Franz Friebel, Chong-Wen Zhou, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 4985–5016, https://doi.org/10.5194/acp-22-4985-2022, https://doi.org/10.5194/acp-22-4985-2022, 2022
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Soot particles impact cloud formation and radiative properties in the upper atmosphere where aircraft emit carbonaceous particles. We use cloud chambers to mimic the upper atmosphere temperature and humidity to test the influence of the morphology of the soot particles on ice cloud formation. For particles larger than 200 nm, the compacted (densified) samples have a higher affinity for ice crystal formation in the cirrus regime than the fluffy (un-compacted) soot particles of the same sample.
Joel Kuula, Hilkka Timonen, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Tareq Hussein, Pak Lun Fung, Sasu Tarkoma, Mikko Laakso, Erkka Saukko, Aino Ovaska, Markku Kulmala, Ari Karppinen, Lasse Johansson, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 4801–4808, https://doi.org/10.5194/acp-22-4801-2022, https://doi.org/10.5194/acp-22-4801-2022, 2022
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Modern and up-to-date policies and air quality management strategies are instrumental in tackling global air pollution. As the European Union is preparing to revise Ambient Air Quality Directive 2008/50/EC, this paper initiates discussion on selected features of the directive that we believe would benefit from a reassessment. The scientific community has the most recent and deepest understanding of air pollution; thus, its contribution is essential.
Yu Wang, Aristeidis Voliotis, Dawei Hu, Yunqi Shao, Mao Du, Ying Chen, Judith Kleinheins, Claudia Marcolli, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 4149–4166, https://doi.org/10.5194/acp-22-4149-2022, https://doi.org/10.5194/acp-22-4149-2022, 2022
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Aerosol water uptake plays a key role in atmospheric physicochemical processes. We designed chamber experiments on aerosol water uptake of secondary organic aerosol (SOA) from mixed biogenic and anthropogenic precursors with inorganic seed. Our results highlight this chemical composition influences the reconciliation of the sub- and super-saturated water uptake, providing laboratory evidence for understanding the chemical controls of water uptake of the multi-component aerosol.
Shuang Han, Juan Hong, Qingwei Luo, Hanbing Xu, Haobo Tan, Qiaoqiao Wang, Jiangchuan Tao, Yaqing Zhou, Long Peng, Yao He, Jingnan Shi, Nan Ma, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 3985–4004, https://doi.org/10.5194/acp-22-3985-2022, https://doi.org/10.5194/acp-22-3985-2022, 2022
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We present the hygroscopicity of 23 organic species with different physicochemical properties using a hygroscopicity tandem differential mobility analyzer (HTDMA) and compare the results with previous studies. Based on the hygroscopicity parameter κ, the influence of different physicochemical properties that potentially drive hygroscopicity, such as the functionality, water solubility, molar volume, and O : C ratio of organics, are examined separately.
Kimmo Korhonen, Thomas Bjerring Kristensen, John Falk, Vilhelm B. Malmborg, Axel Eriksson, Louise Gren, Maja Novakovic, Sam Shamun, Panu Karjalainen, Lassi Markkula, Joakim Pagels, Birgitta Svenningsson, Martin Tunér, Mika Komppula, Ari Laaksonen, and Annele Virtanen
Atmos. Chem. Phys., 22, 1615–1631, https://doi.org/10.5194/acp-22-1615-2022, https://doi.org/10.5194/acp-22-1615-2022, 2022
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We investigated the ice-nucleating abilities of particulate emissions from a modern diesel engine using the portable ice-nuclei counter SPIN, a continuous-flow diffusion chamber instrument. Three different fuels were studied without blending, including fossil diesel and two renewable fuels, testing different emission aftertreatment systems and photochemical aging. We found that the diesel emissions were inefficient ice nuclei, and aging had no or little effect on their ice-nucleating abilities.
Noora Hyttinen, Iida Pullinen, Aki Nissinen, Siegfried Schobesberger, Annele Virtanen, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 1195–1208, https://doi.org/10.5194/acp-22-1195-2022, https://doi.org/10.5194/acp-22-1195-2022, 2022
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Accurate saturation vapor pressure estimates of atmospherically relevant organic compounds are critical for modeling secondary organic aerosol (SOA) formation. We investigated vapor pressures of highly oxygenated SOA constituents using state-of-the-art computational and experimental methods. We found a good agreement between low and extremely low vapor pressures estimated using the two methods, and the smallest molecules detected in our experiment were likely products of thermal decomposition.
Dawei Hu, M. Rami Alfarra, Kate Szpek, Justin M. Langridge, Michael I. Cotterell, Claire Belcher, Ian Rule, Zixia Liu, Chenjie Yu, Yunqi Shao, Aristeidis Voliotis, Mao Du, Brett Smith, Greg Smallwood, Prem Lobo, Dantong Liu, Jim M. Haywood, Hugh Coe, and James D. Allan
Atmos. Chem. Phys., 21, 16161–16182, https://doi.org/10.5194/acp-21-16161-2021, https://doi.org/10.5194/acp-21-16161-2021, 2021
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Here, we developed new techniques for investigating these properties in the laboratory and applied these to BC and BrC from different sources, including diesel exhaust, inverted propane flame and wood combustion. These have allowed us to quantify the changes in shape and chemical composition of different soots according to source and variables such as the moisture content of wood.
Mariam Fawaz, Anita Avery, Timothy B. Onasch, Leah R. Williams, and Tami C. Bond
Atmos. Chem. Phys., 21, 15605–15618, https://doi.org/10.5194/acp-21-15605-2021, https://doi.org/10.5194/acp-21-15605-2021, 2021
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Biomass burning is responsible for 90 % of the emissions of primary organic aerosols to the atmosphere. Emissions from biomass burning sources are considered chaotic. In this work, we developed a controlled experimental approach to understand the controlling factors in emission. Our results showed that emissions are repeatable and deterministic and that emissions from wood can be constrained.
Soleil E. Worthy, Anand Kumar, Yu Xi, Jingwei Yun, Jessie Chen, Cuishan Xu, Victoria E. Irish, Pierre Amato, and Allan K. Bertram
Atmos. Chem. Phys., 21, 14631–14648, https://doi.org/10.5194/acp-21-14631-2021, https://doi.org/10.5194/acp-21-14631-2021, 2021
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We studied the effect of (NH4)2SO4 on the immersion freezing of non-mineral dust ice-nucleating substances (INSs) and mineral dusts. (NH4)2SO4 had no effect on the median freezing temperature of 9 of the 10 tested non-mineral dust INSs, slightly decreased that of the other, and increased that of all the mineral dusts. The difference in the response of mineral dust and non-mineral dust INSs to (NH4)2SO4 suggests that they nucleate ice and/or interact with (NH4)2SO4 via different mechanisms.
Robert Wagner, Luisa Ickes, Allan K. Bertram, Nora Els, Elena Gorokhova, Ottmar Möhler, Benjamin J. Murray, Nsikanabasi Silas Umo, and Matthew E. Salter
Atmos. Chem. Phys., 21, 13903–13930, https://doi.org/10.5194/acp-21-13903-2021, https://doi.org/10.5194/acp-21-13903-2021, 2021
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Sea spray aerosol particles are a mixture of inorganic salts and organic matter from phytoplankton organisms. At low temperatures in the upper troposphere, both inorganic and organic constituents can induce the formation of ice crystals and thereby impact cloud properties and climate. In this study, we performed experiments in a cloud simulation chamber with particles produced from Arctic seawater samples to quantify the relative contribution of inorganic and organic species in ice formation.
Matthew Ozon, Dominik Stolzenburg, Lubna Dada, Aku Seppänen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 21, 12595–12611, https://doi.org/10.5194/acp-21-12595-2021, https://doi.org/10.5194/acp-21-12595-2021, 2021
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Measuring the rate at which aerosol particles are formed is of importance for understanding climate change. We present an analysis method based on Kalman smoothing, which retrieves new particle formation and growth rates from size-distribution measurements. We apply it to atmospheric simulation chamber experiments and show that it agrees well with traditional methods. In addition, it provides reliable uncertainty estimates, and we suggest instrument design optimisation for signal processing.
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