Articles | Volume 20, issue 23
https://doi.org/10.5194/acp-20-14889-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-20-14889-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Dec 2020
Research article |
| 03 Dec 2020
| 03 Dec 2020
Application of holography and automated image processing for laboratory experiments on mass and fall speed of small cloud ice crystals
Maximilian Weitzel
Particle Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Subir K. Mitra
Particle Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Institute of Atmospheric Physics, University of Mainz, Mainz, Germany
Jacob P. Fugal
Institute of Atmospheric Physics, University of Mainz, Mainz, Germany
now at: SeeReal Technologies, Dresden, Germany
Stephan Borrmann
Particle Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Institute of Atmospheric Physics, University of Mainz, Mainz, Germany
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Jackson Seymore, Martanda Gautam, Miklós Szakáll, Alexander Theis, Thorsten Hoffmann, Jialiang Ma, Lingli Zhou, and Alexander Vogel
EGUsphere, https://doi.org/10.5194/egusphere-2024-3940, https://doi.org/10.5194/egusphere-2024-3940, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We investigated the chemical retention of water-soluble organic compounds in Beijing aerosols using an acoustic levitator and drop freezing experiments. Samples from PM2.5 filter extracts were frozen at -15 °C without artificial nucleators and analyzed using ultra-high resolution mass spectrometry. Our findings reveal a nonnormal distribution of retention coefficients that differs from current literature on cloud droplets.
Martanda Gautam, Alexander Theis, Jackson Seymore, Moritz Hey, Stephan Borrmann, Karoline Diehl, Subir K. Mitra, and Miklós Szakáll
EGUsphere, https://doi.org/10.5194/egusphere-2024-3917, https://doi.org/10.5194/egusphere-2024-3917, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We investigated the retention of chemical species and their binary mixtures during freezing of raindrops via acoustic levitation. Our results reveal high retention-nearly all substances being fully retained during freezing. This could be attributed to faster freezing time compared to slower mass expulsion time, along with ice-shell formation during freezing. This result helps improve our understanding of interaction between ice microphysical processes and chemistry in deep convective clouds.
Christine Borchers, Jackson Seymore, Martanda Gautam, Konstantin Dörholt, Yannik Müller, Andreas Arndt, Laura Gömmer, Florian Ungeheuer, Miklós Szakáll, Stephan Borrmann, Alexander Theis, Alexander L. Vogel, and Thorsten Hoffmann
Atmos. Chem. Phys., 24, 13961–13974, https://doi.org/10.5194/acp-24-13961-2024, https://doi.org/10.5194/acp-24-13961-2024, 2024
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Riming, a crucial process in cloud dynamics, influences the vertical distribution of compounds in the atmosphere. Experiments in Mainz's wind tunnel investigated retention coefficients of organic compounds under varying conditions. Findings suggest a correlation between the Henry's law constant and retention, applicable even to complex organic molecules.
Sudha Yadav, Lilly Metten, Pierre Grzegorczyk, Alexander Theis, Subir Kumar Mitra, and Miklós Szakáll
EGUsphere, https://doi.org/10.5194/egusphere-2024-3222, https://doi.org/10.5194/egusphere-2024-3222, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We conducted laboratory studies on the fragmentation of ice particles by collision. Graupels were created by riming at -7 and -15 °C simulating also rotation and tumbling. Ice pellets were generated by freezing water in 3D-printed spherical molds. The number of fragments generated by collision was between 1 and 20, and strongly dependent on the density of the graupel. We also showed that the number of fragments becomes zero when the particle suffers more than three collisions in a row.
Julia Pikmann, Frank Drewnick, Friederike Fachinger, and Stephan Borrmann
Atmos. Chem. Phys., 24, 12295–12321, https://doi.org/10.5194/acp-24-12295-2024, https://doi.org/10.5194/acp-24-12295-2024, 2024
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Cooking activities can contribute substantially to indoor and ambient aerosol. We performed a comprehensive study with laboratory measurements cooking 19 different dishes and ambient measurements at two Christmas markets measuring various particle properties and trace gases of emissions in real time. Similar emission characteristics were observed for dishes with the same preparation method, mainly due to similar cooking temperature and use of oil, with barbecuing as an especially strong source.
Manfred Wendisch, Susanne Crewell, André Ehrlich, Andreas Herber, Benjamin Kirbus, Christof Lüpkes, Mario Mech, Steven J. Abel, Elisa F. Akansu, Felix Ament, Clémantyne Aubry, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Marlen Brückner, Hans-Christian Clemen, Sandro Dahlke, Georgios Dekoutsidis, Julien Delanoë, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Irina V. Gorodetskaya, Sarah Grawe, Silke Groß, Jörg Hartmann, Silvia Henning, Lutz Hirsch, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsofia Jurányi, Michail Karalis, Mona Kellermann, Marcus Klingebiel, Michael Lonardi, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Marion Maturilli, Bernhard Mayer, Johanna Mayer, Stephan Mertes, Janosch Michaelis, Michel Michalkov, Guillaume Mioche, Manuel Moser, Hanno Müller, Roel Neggers, Davide Ori, Daria Paul, Fiona M. Paulus, Christian Pilz, Felix Pithan, Mira Pöhlker, Veronika Pörtge, Maximilian Ringel, Nils Risse, Gregory C. Roberts, Sophie Rosenburg, Johannes Röttenbacher, Janna Rückert, Michael Schäfer, Jonas Schaefer, Vera Schemann, Imke Schirmacher, Jörg Schmidt, Sebastian Schmidt, Johannes Schneider, Sabrina Schnitt, Anja Schwarz, Holger Siebert, Harald Sodemann, Tim Sperzel, Gunnar Spreen, Bjorn Stevens, Frank Stratmann, Gunilla Svensson, Christian Tatzelt, Thomas Tuch, Timo Vihma, Christiane Voigt, Lea Volkmer, Andreas Walbröl, Anna Weber, Birgit Wehner, Bruno Wetzel, Martin Wirth, and Tobias Zinner
Atmos. Chem. Phys., 24, 8865–8892, https://doi.org/10.5194/acp-24-8865-2024, https://doi.org/10.5194/acp-24-8865-2024, 2024
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The Arctic is warming faster than the rest of the globe. Warm-air intrusions (WAIs) into the Arctic may play an important role in explaining this phenomenon. Cold-air outbreaks (CAOs) out of the Arctic may link the Arctic climate changes to mid-latitude weather. In our article, we describe how to observe air mass transformations during CAOs and WAIs using three research aircraft instrumented with state-of-the-art remote-sensing and in situ measurement devices.
André Ehrlich, Susanne Crewell, Andreas Herber, Marcus Klingebiel, Christof Lüpkes, Mario Mech, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Matthias Buschmann, Hans-Christian Clemen, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Andreas Giez, Sarah Grawe, Christophe Gourbeyre, Jörg Hartmann, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsófia Jurányi, Benjamin Kirbus, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Christian Mallaun, Johanna Mayer, Stephan Mertes, Guillaume Mioche, Manuel Moser, Hanno Müller, Veronika Pörtge, Nils Risse, Greg Roberts, Sophie Rosenburg, Johannes Röttenbacher, Michael Schäfer, Jonas Schaefer, Andreas Schäfler, Imke Schirmacher, Johannes Schneider, Sabrina Schnitt, Frank Stratmann, Christian Tatzelt, Christiane Voigt, Andreas Walbröl, Anna Weber, Bruno Wetzel, Martin Wirth, and Manfred Wendisch
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-281, https://doi.org/10.5194/essd-2024-281, 2024
Revised manuscript under review for ESSD
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This paper provides an overview of the HALO–(AC)3 aircraft campaign data sets, the campaign specific instrument operation, data processing, and data quality. The data set comprises in-situ and remote sensing observations from three research aircraft, HALO, Polar 5, and Polar 6. All data are published in the PANGAEA database by instrument-separated data subsets. It is highlighted how the scientific analysis of the HALO–(AC)3 data benefits from the coordinated operation of three aircraft.
Philipp Joppe, Johannes Schneider, Katharina Kaiser, Horst Fischer, Peter Hoor, Daniel Kunkel, Hans-Christoph Lachnitt, Andreas Marsing, Lenard Röder, Hans Schlager, Laura Tomsche, Christiane Voigt, Andreas Zahn, and Stephan Borrmann
Atmos. Chem. Phys., 24, 7499–7522, https://doi.org/10.5194/acp-24-7499-2024, https://doi.org/10.5194/acp-24-7499-2024, 2024
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From aircraft measurements in the upper troposphere/lower stratosphere, we find a correlation between the ozone and particulate sulfate in the lower stratosphere. The correlation exhibits some variability over the measurement period exceeding the background sulfate-to-ozone correlation. From our analysis, we conclude that gas-to-particle conversion of volcanic sulfur dioxide leads to observed enhanced sulfate aerosol mixing ratios.
Martin Ebert, Ralf Weigel, Stephan Weinbruch, Lisa Schneider, Konrad Kandler, Stefan Lauterbach, Franziska Köllner, Felix Plöger, Gebhard Günther, Bärbel Vogel, and Stephan Borrmann
Atmos. Chem. Phys., 24, 4771–4788, https://doi.org/10.5194/acp-24-4771-2024, https://doi.org/10.5194/acp-24-4771-2024, 2024
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Particles were collected during the flight campaign StratoClim 2017 within the Asian tropopause aerosol layer (ATAL). Refractory particles from seven different flights were characterized by scanning and transmission electron microscopy (SEM, TEM). The most abundant refractory particles are silicates and non-volatile organics. The most important sources are combustion processes at the ground and the agitation of soil material. During one flight, small cinnabar particles (HgS) were also detected.
Adrien Deroubaix, Marco Vountas, Benjamin Gaubert, Maria Dolores Andrés Hernández, Stephan Borrmann, Guy Brasseur, Bruna Holanda, Yugo Kanaya, Katharina Kaiser, Flora Kluge, Ovid Oktavian Krüger, Inga Labuhn, Michael Lichtenstern, Klaus Pfeilsticker, Mira Pöhlker, Hans Schlager, Johannes Schneider, Guillaume Siour, Basudev Swain, Paolo Tuccella, Kameswara S. Vinjamuri, Mihalis Vrekoussis, Benjamin Weyland, and John P. Burrows
EGUsphere, https://doi.org/10.5194/egusphere-2024-516, https://doi.org/10.5194/egusphere-2024-516, 2024
Preprint archived
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This study assesses atmospheric composition using air quality models during aircraft campaigns in Europe and Asia, focusing on carbonaceous aerosols and trace gases. While carbon monoxide is well modeled, other pollutants have moderate to weak agreement with observations. Wind speed modeling is reliable for identifying pollution plumes, where models tend to overestimate concentrations. This highlights challenges in accurately modeling aerosol and trace gas composition, particularly in cities.
Adrien Deroubaix, Marco Vountas, Benjamin Gaubert, Maria Dolores Andrés Hernández, Stephan Borrmann, Guy Brasseur, Bruna Holanda, Yugo Kanaya, Katharina Kaiser, Flora Kluge, Ovid Oktavian Krüger, Inga Labuhn, Michael Lichtenstern, Klaus Pfeilsticker, Mira Pöhlker, Hans Schlager, Johannes Schneider, Guillaume Siour, Basudev Swain, Paolo Tuccella, Kameswara S. Vinjamuri, Mihalis Vrekoussis, Benjamin Weyland, and John P. Burrows
EGUsphere, https://doi.org/10.5194/egusphere-2024-521, https://doi.org/10.5194/egusphere-2024-521, 2024
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This study explores the proportional relationships between carbonaceous aerosols (black and organic carbon) and trace gases using airborne measurements from two campaigns in Europe and East Asia. Differences between regions were found, but air quality models struggled to reproduce them accurately. We show that these proportional relationships can help to constrain models and can be used to infer aerosol concentrations from satellite observations of trace gases, especially in urban areas.
Francesco Cairo, Martina Krämer, Armin Afchine, Guido Di Donfrancesco, Luca Di Liberto, Sergey Khaykin, Lorenza Lucaferri, Valentin Mitev, Max Port, Christian Rolf, Marcel Snels, Nicole Spelten, Ralf Weigel, and Stephan Borrmann
Atmos. Meas. Tech., 16, 4899–4925, https://doi.org/10.5194/amt-16-4899-2023, https://doi.org/10.5194/amt-16-4899-2023, 2023
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Cirrus clouds have been observed over the Himalayan region between 10 km and the tropopause at 17–18 km. Data from backscattersonde, hygrometers, and particle cloud spectrometers have been compared to assess their consistency. Empirical relationships between optical parameters accessible with remote sensing lidars and cloud microphysical parameters (such as ice water content, particle number and surface area density, and particle aspherical fraction) have been established.
Pierre Grzegorczyk, Sudha Yadav, Florian Zanger, Alexander Theis, Subir K. Mitra, Stephan Borrmann, and Miklós Szakáll
Atmos. Chem. Phys., 23, 13505–13521, https://doi.org/10.5194/acp-23-13505-2023, https://doi.org/10.5194/acp-23-13505-2023, 2023
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Secondary ice production generates high concentrations of ice crystals in clouds. These processes have been poorly understood. We conducted experiments at the wind tunnel laboratory of the Johannes Gutenberg University, Mainz, on graupel–graupel and graupel–snowflake collisions. From these experiments fragment number, size, cross-sectional area, and aspect ratio were determined.
Manuel Moser, Christiane Voigt, Tina Jurkat-Witschas, Valerian Hahn, Guillaume Mioche, Olivier Jourdan, Régis Dupuy, Christophe Gourbeyre, Alfons Schwarzenboeck, Johannes Lucke, Yvonne Boose, Mario Mech, Stephan Borrmann, André Ehrlich, Andreas Herber, Christof Lüpkes, and Manfred Wendisch
Atmos. Chem. Phys., 23, 7257–7280, https://doi.org/10.5194/acp-23-7257-2023, https://doi.org/10.5194/acp-23-7257-2023, 2023
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This study provides a comprehensive microphysical and thermodynamic phase analysis of low-level clouds in the northern Fram Strait, above the sea ice and the open ocean, during spring and summer. Using airborne in situ cloud data, we show that the properties of Arctic low-level clouds vary significantly with seasonal meteorological situations and surface conditions. The observations presented in this study can help one to assess the role of clouds in the Arctic climate system.
Julia Pikmann, Lasse Moormann, Frank Drewnick, and Stephan Borrmann
Atmos. Meas. Tech., 16, 1323–1341, https://doi.org/10.5194/amt-16-1323-2023, https://doi.org/10.5194/amt-16-1323-2023, 2023
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Aerosols measured in complex environments are usually a mixture of emissions from different sources. To characterize sources individually, we developed a sampling system for particles and organic trace gases which is coupled to real-time data of physical and chemical aerosol properties, gas concentrations, and meteorological variables. Using suitable sampling conditions for individual aerosols which are compared with the real-time data the desired aerosols are sampled separately from each other.
Oliver Appel, Franziska Köllner, Antonis Dragoneas, Andreas Hünig, Sergej Molleker, Hans Schlager, Christoph Mahnke, Ralf Weigel, Max Port, Christiane Schulz, Frank Drewnick, Bärbel Vogel, Fred Stroh, and Stephan Borrmann
Atmos. Chem. Phys., 22, 13607–13630, https://doi.org/10.5194/acp-22-13607-2022, https://doi.org/10.5194/acp-22-13607-2022, 2022
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This paper clarifies the chemical composition of the Asian tropopause aerosol layer (ATAL) by means of airborne in situ aerosol mass spectrometry (AMS). Ammonium nitrate and organics are found to significantly contribute to the particle layer, while sulfate does not show a layered structure. An analysis of the single-particle mass spectra suggests that secondary particle formation and subsequent growth dominate the particle composition, rather than condensation on pre-existing primary particles.
Antonis Dragoneas, Sergej Molleker, Oliver Appel, Andreas Hünig, Thomas Böttger, Markus Hermann, Frank Drewnick, Johannes Schneider, Ralf Weigel, and Stephan Borrmann
Atmos. Meas. Tech., 15, 5719–5742, https://doi.org/10.5194/amt-15-5719-2022, https://doi.org/10.5194/amt-15-5719-2022, 2022
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The ERICA is a specially designed aerosol particle mass spectrometer for in situ, real-time chemical composition analysis of aerosols. It can operate completely autonomously, in the absence of an instrument operator. Its design has enabled its operation under harsh conditions, like those experienced in the upper troposphere and lower stratosphere, aboard unpressurized high-altitude research aircraft. The instrument has successfully participated in several aircraft operations around the world.
Andreas Hünig, Oliver Appel, Antonis Dragoneas, Sergej Molleker, Hans-Christian Clemen, Frank Helleis, Thomas Klimach, Franziska Köllner, Thomas Böttger, Frank Drewnick, Johannes Schneider, and Stephan Borrmann
Atmos. Meas. Tech., 15, 2889–2921, https://doi.org/10.5194/amt-15-2889-2022, https://doi.org/10.5194/amt-15-2889-2022, 2022
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We have serially combined the two well-established methods for in situ real-time measurement of fine particle chemical composition, the single-particle laser ablation method and the flash evaporation with electron impact ionization method, into a novel instrument. Here we present the design; instrument characteristics, as derived from laboratory and field measurements; and results from the first field deployment during the 2017 StratoClim aircraft campaign.
M. Dolores Andrés Hernández, Andreas Hilboll, Helmut Ziereis, Eric Förster, Ovid O. Krüger, Katharina Kaiser, Johannes Schneider, Francesca Barnaba, Mihalis Vrekoussis, Jörg Schmidt, Heidi Huntrieser, Anne-Marlene Blechschmidt, Midhun George, Vladyslav Nenakhov, Theresa Harlass, Bruna A. Holanda, Jennifer Wolf, Lisa Eirenschmalz, Marc Krebsbach, Mira L. Pöhlker, Anna B. Kalisz Hedegaard, Linlu Mei, Klaus Pfeilsticker, Yangzhuoran Liu, Ralf Koppmann, Hans Schlager, Birger Bohn, Ulrich Schumann, Andreas Richter, Benjamin Schreiner, Daniel Sauer, Robert Baumann, Mariano Mertens, Patrick Jöckel, Markus Kilian, Greta Stratmann, Christopher Pöhlker, Monica Campanelli, Marco Pandolfi, Michael Sicard, José L. Gómez-Amo, Manuel Pujadas, Katja Bigge, Flora Kluge, Anja Schwarz, Nikos Daskalakis, David Walter, Andreas Zahn, Ulrich Pöschl, Harald Bönisch, Stephan Borrmann, Ulrich Platt, and John P. Burrows
Atmos. Chem. Phys., 22, 5877–5924, https://doi.org/10.5194/acp-22-5877-2022, https://doi.org/10.5194/acp-22-5877-2022, 2022
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EMeRGe provides a unique set of in situ and remote sensing airborne measurements of trace gases and aerosol particles along selected flight routes in the lower troposphere over Europe. The interpretation uses also complementary collocated ground-based and satellite measurements. The collected data help to improve the current understanding of the complex spatial distribution of trace gases and aerosol particles resulting from mixing, transport, and transformation of pollution plumes over Europe.
Yu-Wen Chen, Yi-Chun Chen, Charles C.-K. Chou, Hui-Ming Hung, Shih-Yu Chang, Lisa Eirenschmalz, Michael Lichtenstern, Helmut Ziereis, Hans Schlager, Greta Stratmann, Katharina Kaiser, Johannes Schneider, Stephan Borrmann, Florian Obersteiner, Eric Förster, Andreas Zahn, Wei-Nai Chen, Po-Hsiung Lin, Shuenn-Chin Chang, Maria Dolores Andrés Hernández, Pao-Kuan Wang, and John P. Burrows
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-788, https://doi.org/10.5194/acp-2021-788, 2021
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By presenting an approach using EMeRGe-Asia airborne field measurements and surface observations, this study shows that the fraction of OH reactivity due to SO2-OH reaction has a significant correlation with the sulfate concentration. Approximately 30 % of sulfate is produced by SO2-OH reaction. Our results underline the importance of SO2-OH gas-phase oxidation in sulfate formation, and demonstrate that the method can be applied to other regions and under different meteorological conditions.
Christoph Mahnke, Ralf Weigel, Francesco Cairo, Jean-Paul Vernier, Armin Afchine, Martina Krämer, Valentin Mitev, Renaud Matthey, Silvia Viciani, Francesco D'Amato, Felix Ploeger, Terry Deshler, and Stephan Borrmann
Atmos. Chem. Phys., 21, 15259–15282, https://doi.org/10.5194/acp-21-15259-2021, https://doi.org/10.5194/acp-21-15259-2021, 2021
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In 2017, in situ aerosol measurements were conducted aboard the M55 Geophysica in the Asian monsoon region. The vertical particle mixing ratio profiles show a distinct layer (15–18.5 km), the Asian tropopause aerosol layer (ATAL). The backscatter ratio (BR) was calculated based on the aerosol size distributions and compared with the BRs detected by a backscatter probe and a lidar aboard M55, and by the CALIOP lidar. All four methods show enhanced BRs in the ATAL altitude range (max. at 17.5 km).
Ralf Weigel, Christoph Mahnke, Manuel Baumgartner, Martina Krämer, Peter Spichtinger, Nicole Spelten, Armin Afchine, Christian Rolf, Silvia Viciani, Francesco D'Amato, Holger Tost, and Stephan Borrmann
Atmos. Chem. Phys., 21, 13455–13481, https://doi.org/10.5194/acp-21-13455-2021, https://doi.org/10.5194/acp-21-13455-2021, 2021
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In July and August 2017, the StratoClim mission took place in Nepal with eight flights of the M-55 Geophysica at up to 20 km in the Asian monsoon anticyclone. New particle formation (NPF) next to cloud ice was detected in situ by abundant nucleation-mode aerosols (> 6 nm) along with ice particles (> 3 µm). NPF was observed mainly below the tropopause, down to 15 % being non-volatile residues. Observed intra-cloud NPF indicates its importance for the composition in the tropical tropopause layer.
Ralf Weigel, Christoph Mahnke, Manuel Baumgartner, Antonis Dragoneas, Bärbel Vogel, Felix Ploeger, Silvia Viciani, Francesco D'Amato, Silvia Bucci, Bernard Legras, Beiping Luo, and Stephan Borrmann
Atmos. Chem. Phys., 21, 11689–11722, https://doi.org/10.5194/acp-21-11689-2021, https://doi.org/10.5194/acp-21-11689-2021, 2021
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In July and August 2017, eight StratoClim mission flights of the Geophysica reached up to 20 km in the Asian monsoon anticyclone. New particle formation (NPF) was identified in situ by abundant nucleation-mode aerosols (6–15 nm in diameter) with mixing ratios of up to 50 000 mg−1. NPF occurred most frequently at 12–16 km with fractions of non-volatile residues of down to 15 %. Abundance and productivity of observed NPF indicate its ability to promote the Asian tropopause aerosol layer.
Franziska Köllner, Johannes Schneider, Megan D. Willis, Hannes Schulz, Daniel Kunkel, Heiko Bozem, Peter Hoor, Thomas Klimach, Frank Helleis, Julia Burkart, W. Richard Leaitch, Amir A. Aliabadi, Jonathan P. D. Abbatt, Andreas B. Herber, and Stephan Borrmann
Atmos. Chem. Phys., 21, 6509–6539, https://doi.org/10.5194/acp-21-6509-2021, https://doi.org/10.5194/acp-21-6509-2021, 2021
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We present in situ observations of vertically resolved particle chemical composition in the summertime Arctic lower troposphere. Our analysis demonstrates the strong vertical contrast between particle properties within the boundary layer and aloft. Emissions from vegetation fires and anthropogenic sources in northern Canada, Europe, and East Asia influenced particle composition in the free troposphere. Organics detected in Arctic aerosol particles can partly be identified as dicarboxylic acids.
Sebastian O'Shea, Jonathan Crosier, James Dorsey, Louis Gallagher, Waldemar Schledewitz, Keith Bower, Oliver Schlenczek, Stephan Borrmann, Richard Cotton, Christopher Westbrook, and Zbigniew Ulanowski
Atmos. Meas. Tech., 14, 1917–1939, https://doi.org/10.5194/amt-14-1917-2021, https://doi.org/10.5194/amt-14-1917-2021, 2021
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The number, shape, and size of ice crystals in clouds are important properties that influence the Earth's radiation budget, cloud evolution, and precipitation formation. This work suggests that one of the most widely used methods for in situ measurements of these properties has significant uncertainties and biases. We suggest methods that dramatically improve these measurements, which can be applied to past and future datasets from these instruments.
Miklós Szakáll, Michael Debertshäuser, Christian Philipp Lackner, Amelie Mayer, Oliver Eppers, Karoline Diehl, Alexander Theis, Subir Kumar Mitra, and Stephan Borrmann
Atmos. Chem. Phys., 21, 3289–3316, https://doi.org/10.5194/acp-21-3289-2021, https://doi.org/10.5194/acp-21-3289-2021, 2021
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The freezing of cloud drops is promoted by ice-nucleating particles immersed in the drops. This process is essential to understand ice and subsequent precipitation formation in clouds. We investigated the efficiency of several particle types to trigger immersion freezing with two single-drop levitation techniques: a wind tunnel and an acoustic levitator. The evaluation accounted for different conditions during our two series of experiments, which is also applicable to future comparison studies.
Johannes Schneider, Ralf Weigel, Thomas Klimach, Antonis Dragoneas, Oliver Appel, Andreas Hünig, Sergej Molleker, Franziska Köllner, Hans-Christian Clemen, Oliver Eppers, Peter Hoppe, Peter Hoor, Christoph Mahnke, Martina Krämer, Christian Rolf, Jens-Uwe Grooß, Andreas Zahn, Florian Obersteiner, Fabrizio Ravegnani, Alexey Ulanovsky, Hans Schlager, Monika Scheibe, Glenn S. Diskin, Joshua P. DiGangi, John B. Nowak, Martin Zöger, and Stephan Borrmann
Atmos. Chem. Phys., 21, 989–1013, https://doi.org/10.5194/acp-21-989-2021, https://doi.org/10.5194/acp-21-989-2021, 2021
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During five aircraft missions, we detected aerosol particles containing meteoric material in the lower stratosphere. The stratospheric measurements span a latitude range from 15 to 68° N, and we find that at potential temperature levels of more than 40 K above the tropopause; particles containing meteoric material occur at similar abundance fractions across latitudes and seasons. We conclude that meteoric material is efficiently distributed between high and low latitudes by isentropic mixing.
Hans-Christian Clemen, Johannes Schneider, Thomas Klimach, Frank Helleis, Franziska Köllner, Andreas Hünig, Florian Rubach, Stephan Mertes, Heike Wex, Frank Stratmann, André Welti, Rebecca Kohl, Fabian Frank, and Stephan Borrmann
Atmos. Meas. Tech., 13, 5923–5953, https://doi.org/10.5194/amt-13-5923-2020, https://doi.org/10.5194/amt-13-5923-2020, 2020
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We improved the efficiency of a single-particle mass spectrometer with a newly developed aerodynamic lens system, delayed ion extraction, and better electric shielding. The new components result in significantly improved particle analysis and sample statistics. This is particularly important for measurements of low-number-density particles, such as ice-nucleating particles, and for aircraft-based measurements at high altitudes or where high temporal and spatial resolution is required.
Sergej Molleker, Frank Helleis, Thomas Klimach, Oliver Appel, Hans-Christian Clemen, Antonis Dragoneas, Christian Gurk, Andreas Hünig, Franziska Köllner, Florian Rubach, Christiane Schulz, Johannes Schneider, and Stephan Borrmann
Atmos. Meas. Tech., 13, 3651–3660, https://doi.org/10.5194/amt-13-3651-2020, https://doi.org/10.5194/amt-13-3651-2020, 2020
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A novel constant-pressure-inlet design for use in airborne aerosol particle mass spectrometry – an aerodynamic lens focuses aerosol particles into a vacuum chamber – is presented. The pressure of a few hectopascals at the lens is precisely controlled over a large flight altitude range up to 21 km. The constant pressure is achieved by changing the inner diameter of a properly scaled flexible O-ring acting as a critical orifice. Particle transmission at various inlet pressures is characterized.
Bruna A. Holanda, Mira L. Pöhlker, David Walter, Jorge Saturno, Matthias Sörgel, Jeannine Ditas, Florian Ditas, Christiane Schulz, Marco Aurélio Franco, Qiaoqiao Wang, Tobias Donth, Paulo Artaxo, Henrique M. J. Barbosa, Stephan Borrmann, Ramon Braga, Joel Brito, Yafang Cheng, Maximilian Dollner, Johannes W. Kaiser, Thomas Klimach, Christoph Knote, Ovid O. Krüger, Daniel Fütterer, Jošt V. Lavrič, Nan Ma, Luiz A. T. Machado, Jing Ming, Fernando G. Morais, Hauke Paulsen, Daniel Sauer, Hans Schlager, Johannes Schneider, Hang Su, Bernadett Weinzierl, Adrian Walser, Manfred Wendisch, Helmut Ziereis, Martin Zöger, Ulrich Pöschl, Meinrat O. Andreae, and Christopher Pöhlker
Atmos. Chem. Phys., 20, 4757–4785, https://doi.org/10.5194/acp-20-4757-2020, https://doi.org/10.5194/acp-20-4757-2020, 2020
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Biomass burning smoke from African savanna and grassland is transported across the South Atlantic Ocean in defined layers within the free troposphere. The combination of in situ aircraft and ground-based measurements aided by satellite observations showed that these layers are transported into the Amazon Basin during the early dry season. The influx of aged smoke, enriched in black carbon and cloud condensation nuclei, has important implications for the Amazonian aerosol and cloud cycling.
Siddika Celik, Frank Drewnick, Friederike Fachinger, James Brooks, Eoghan Darbyshire, Hugh Coe, Jean-Daniel Paris, Philipp G. Eger, Jan Schuladen, Ivan Tadic, Nils Friedrich, Dirk Dienhart, Bettina Hottmann, Horst Fischer, John N. Crowley, Hartwig Harder, and Stephan Borrmann
Atmos. Chem. Phys., 20, 4713–4734, https://doi.org/10.5194/acp-20-4713-2020, https://doi.org/10.5194/acp-20-4713-2020, 2020
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Analysis of 252 ship emission plumes in the Mediterranean Sea and around the Arabian Peninsula examined particulate- and gas-phase characteristics. By identifying the corresponding ships, source features and plume age were determined. Emission factors (amount of pollutant per kilogram of fuel burned) were calculated and investigated for dependencies on source characteristics, atmospheric conditions, and transport time, providing insight into the most relevant influences on ship emissions.
Gary Lloyd, Thomas Choularton, Keith Bower, Jonathan Crosier, Martin Gallagher, Michael Flynn, James Dorsey, Dantong Liu, Jonathan W. Taylor, Oliver Schlenczek, Jacob Fugal, Stephan Borrmann, Richard Cotton, Paul Field, and Alan Blyth
Atmos. Chem. Phys., 20, 3895–3904, https://doi.org/10.5194/acp-20-3895-2020, https://doi.org/10.5194/acp-20-3895-2020, 2020
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Measurements of liquid and ice cloud particles were made using an aircraft to penetrate fresh growing convective clouds in the tropical Atlantic. We found small ice particles at surprisingly high temperatures just below freezing. At colder temperatures secondary ice processes rapidly generated high concentrations of ice crystals.
Fan Mei, Jian Wang, Jennifer M. Comstock, Ralf Weigel, Martina Krämer, Christoph Mahnke, John E. Shilling, Johannes Schneider, Christiane Schulz, Charles N. Long, Manfred Wendisch, Luiz A. T. Machado, Beat Schmid, Trismono Krisna, Mikhail Pekour, John Hubbe, Andreas Giez, Bernadett Weinzierl, Martin Zoeger, Mira L. Pöhlker, Hans Schlager, Micael A. Cecchini, Meinrat O. Andreae, Scot T. Martin, Suzane S. de Sá, Jiwen Fan, Jason Tomlinson, Stephen Springston, Ulrich Pöschl, Paulo Artaxo, Christopher Pöhlker, Thomas Klimach, Andreas Minikin, Armin Afchine, and Stephan Borrmann
Atmos. Meas. Tech., 13, 661–684, https://doi.org/10.5194/amt-13-661-2020, https://doi.org/10.5194/amt-13-661-2020, 2020
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In 2014, the US DOE G1 aircraft and the German HALO aircraft overflew the Amazon basin to study how aerosols influence cloud cycles under a clean condition and around a tropical megacity. This paper describes how to meaningfully compare similar measurements from two research aircraft and identify the potential measurement issue. We also discuss the uncertainty range for each measurement for further usage in model evaluation and satellite data validation.
Sophie L. Haslett, Jonathan W. Taylor, Mathew Evans, Eleanor Morris, Bernhard Vogel, Alima Dajuma, Joel Brito, Anneke M. Batenburg, Stephan Borrmann, Johannes Schneider, Christiane Schulz, Cyrielle Denjean, Thierry Bourrianne, Peter Knippertz, Régis Dupuy, Alfons Schwarzenböck, Daniel Sauer, Cyrille Flamant, James Dorsey, Ian Crawford, and Hugh Coe
Atmos. Chem. Phys., 19, 15217–15234, https://doi.org/10.5194/acp-19-15217-2019, https://doi.org/10.5194/acp-19-15217-2019, 2019
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Three aircraft datasets from the DACCIWA campaign in summer 2016 are used here to show there is a background mass of pollution present in the lower atmosphere in southern West Africa. We suggest that this likely comes from biomass burning in central and southern Africa, which has been carried into the region over the Atlantic Ocean. This would have a negative health impact on populations living near the coast and may alter the impact of growing city emissions on cloud formation and the monsoon.
Sebastian J. O'Shea, Jonathan Crosier, James Dorsey, Waldemar Schledewitz, Ian Crawford, Stephan Borrmann, Richard Cotton, and Aaron Bansemer
Atmos. Meas. Tech., 12, 3067–3079, https://doi.org/10.5194/amt-12-3067-2019, https://doi.org/10.5194/amt-12-3067-2019, 2019
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Optical array probe measurements of clouds are widely used to inform and validate numerical weather and climate models. In this paper, we discuss artefacts which may bias data from these instruments. Using laboratory and synthetic datasets, we demonstrate how greyscale analysis can be used to filter data, constraining the sample volume and improving data quality particularly at small sizes where their measurements are considered unreliable.
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.
Michael Weger, Bernd Heinold, Christa Engler, Ulrich Schumann, Axel Seifert, Romy Fößig, Christiane Voigt, Holger Baars, Ulrich Blahak, Stephan Borrmann, Corinna Hoose, Stefan Kaufmann, Martina Krämer, Patric Seifert, Fabian Senf, Johannes Schneider, and Ina Tegen
Atmos. Chem. Phys., 18, 17545–17572, https://doi.org/10.5194/acp-18-17545-2018, https://doi.org/10.5194/acp-18-17545-2018, 2018
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The impact of desert dust on cloud formation is investigated for a major Saharan dust event over Europe by interactive regional dust modeling. Dust particles are very efficient ice-nucleating particles promoting the formation of ice crystals in clouds. The simulations show that the observed extensive cirrus development was likely related to the above-average dust load. The interactive dust–cloud feedback in the model significantly improves the agreement with aircraft and satellite observations.
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.
Christiane Schulz, Johannes Schneider, Bruna Amorim Holanda, Oliver Appel, Anja Costa, Suzane S. de Sá, Volker Dreiling, Daniel Fütterer, Tina Jurkat-Witschas, Thomas Klimach, Christoph Knote, Martina Krämer, Scot T. Martin, Stephan Mertes, Mira L. Pöhlker, Daniel Sauer, Christiane Voigt, Adrian Walser, Bernadett Weinzierl, Helmut Ziereis, Martin Zöger, Meinrat O. Andreae, Paulo Artaxo, Luiz A. T. Machado, Ulrich Pöschl, Manfred Wendisch, and Stephan Borrmann
Atmos. Chem. Phys., 18, 14979–15001, https://doi.org/10.5194/acp-18-14979-2018, https://doi.org/10.5194/acp-18-14979-2018, 2018
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Aerosol chemical composition measurements in the tropical upper troposphere over the Amazon region show that 78 % of the aerosol in the upper troposphere consists of organic matter. Up to 20 % of the organic aerosol can be attributed to isoprene epoxydiol secondary organic aerosol (IEPOX-SOA). Furthermore, organic nitrates were identified, suggesting a connection to the IEPOX-SOA formation.
Aurélien Chauvigné, Olivier Jourdan, Alfons Schwarzenboeck, Christophe Gourbeyre, Jean François Gayet, Christiane Voigt, Hans Schlager, Stefan Kaufmann, Stephan Borrmann, Sergej Molleker, Andreas Minikin, Tina Jurkat, and Ulrich Schumann
Atmos. Chem. Phys., 18, 9803–9822, https://doi.org/10.5194/acp-18-9803-2018, https://doi.org/10.5194/acp-18-9803-2018, 2018
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This paper demonstrates a new form of statistical analysis of contrail to cirrus evolution. The authors show well-separated analyses of the different stages of the contrail's evolution, which allows us to study their optical, microphysical, and chemical properties. These results could be used to develop representative parameterizations of the scattering and geometrical properties of the ice crystals’ shapes and sizes, observed in the visible wavelength range.
Luiz A. T. Machado, Alan J. P. Calheiros, Thiago Biscaro, Scott Giangrande, Maria A. F. Silva Dias, Micael A. Cecchini, Rachel Albrecht, Meinrat O. Andreae, Wagner F. Araujo, Paulo Artaxo, Stephan Borrmann, Ramon Braga, Casey Burleyson, Cristiano W. Eichholz, Jiwen Fan, Zhe Feng, Gilberto F. Fisch, Michael P. Jensen, Scot T. Martin, Ulrich Pöschl, Christopher Pöhlker, Mira L. Pöhlker, Jean-François Ribaud, Daniel Rosenfeld, Jaci M. B. Saraiva, Courtney Schumacher, Ryan Thalman, David Walter, and Manfred Wendisch
Atmos. Chem. Phys., 18, 6461–6482, https://doi.org/10.5194/acp-18-6461-2018, https://doi.org/10.5194/acp-18-6461-2018, 2018
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This overview discuss the main precipitation processes and their sensitivities to environmental conditions in the Central Amazon Basin. It presents a review of the knowledge acquired about cloud processes and rainfall formation in Amazonas. In addition, this study provides a characterization of the seasonal variation and rainfall sensitivities to topography, surface cover, and aerosol concentration. Airplane measurements were evaluated to characterize and contrast cloud microphysical properties.
Paul Herenz, Heike Wex, Silvia Henning, Thomas Bjerring Kristensen, Florian Rubach, Anja Roth, Stephan Borrmann, Heiko Bozem, Hannes Schulz, and Frank Stratmann
Atmos. Chem. Phys., 18, 4477–4496, https://doi.org/10.5194/acp-18-4477-2018, https://doi.org/10.5194/acp-18-4477-2018, 2018
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The Arctic climate is changing much faster than other regions on Earth. Hence, it is necessary to investigate the processes that are liable for this phenomena and to document the current situation in the Arctic. Therefore, we measured the number and also the size of aerosol particles. It turned out that we captured the transition from the Arctic spring to the Arctic summer and that the according air masses show differences in particle properties. Also, the particles have a low water receptivity.
Trismono C. Krisna, Manfred Wendisch, André Ehrlich, Evelyn Jäkel, Frank Werner, Ralf Weigel, Stephan Borrmann, Christoph Mahnke, Ulrich Pöschl, Meinrat O. Andreae, Christiane Voigt, and Luiz A. T. Machado
Atmos. Chem. Phys., 18, 4439–4462, https://doi.org/10.5194/acp-18-4439-2018, https://doi.org/10.5194/acp-18-4439-2018, 2018
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The optical thickness and particle effective radius of a cirrus above liquid water clouds and a DCC topped by an anvil cirrus are retrieved based on SMART and MODIS radiance measurements. For the cirrus, retrieved particle effective radius are validated with corresponding in situ data using a vertical weighting method. This approach allows to assess the measurements, retrieval algorithms, and derived cloud products.
Meinrat O. Andreae, Armin Afchine, Rachel Albrecht, Bruna Amorim Holanda, Paulo Artaxo, Henrique M. J. Barbosa, Stephan Borrmann, Micael A. Cecchini, Anja Costa, Maximilian Dollner, Daniel Fütterer, Emma Järvinen, Tina Jurkat, Thomas Klimach, Tobias Konemann, Christoph Knote, Martina Krämer, Trismono Krisna, Luiz A. T. Machado, Stephan Mertes, Andreas Minikin, Christopher Pöhlker, Mira L. Pöhlker, Ulrich Pöschl, Daniel Rosenfeld, Daniel Sauer, Hans Schlager, Martin Schnaiter, Johannes Schneider, Christiane Schulz, Antonio Spanu, Vinicius B. Sperling, Christiane Voigt, Adrian Walser, Jian Wang, Bernadett Weinzierl, Manfred Wendisch, and Helmut Ziereis
Atmos. Chem. Phys., 18, 921–961, https://doi.org/10.5194/acp-18-921-2018, https://doi.org/10.5194/acp-18-921-2018, 2018
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We made airborne measurements of aerosol particle concentrations and properties over the Amazon Basin. We found extremely high concentrations of very small particles in the region between 8 and 14 km altitude all across the basin, which had been recently formed by gas-to-particle conversion at these altitudes. This makes the upper troposphere a very important source region of atmospheric particles with significant implications for the Earth's climate system.
Joel Brito, Evelyn Freney, Pamela Dominutti, Agnes Borbon, Sophie L. Haslett, Anneke M. Batenburg, Aurelie Colomb, Regis Dupuy, Cyrielle Denjean, Frederic Burnet, Thierry Bourriane, Adrien Deroubaix, Karine Sellegri, Stephan Borrmann, Hugh Coe, Cyrille Flamant, Peter Knippertz, and Alfons Schwarzenboeck
Atmos. Chem. Phys., 18, 757–772, https://doi.org/10.5194/acp-18-757-2018, https://doi.org/10.5194/acp-18-757-2018, 2018
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This work focuses on sources of submicron aerosol particles over southern West Africa (SWA). Results have shown that isoprene, a gas-phase compound of biogenic origin, is responsible for roughly 25 % of the organic aerosol (OA) loading, under most background or urban plumes alike. This fraction represents a lower estimate from the biogenic contribution in this fairly polluted region. This work sheds light upon the role of anthropogenic and biogenic emissions on the pollution burden over SWA.
Micael A. Cecchini, Luiz A. T. Machado, Manfred Wendisch, Anja Costa, Martina Krämer, Meinrat O. Andreae, Armin Afchine, Rachel I. Albrecht, Paulo Artaxo, Stephan Borrmann, Daniel Fütterer, Thomas Klimach, Christoph Mahnke, Scot T. Martin, Andreas Minikin, Sergej Molleker, Lianet H. Pardo, Christopher Pöhlker, Mira L. Pöhlker, Ulrich Pöschl, Daniel Rosenfeld, and Bernadett Weinzierl
Atmos. Chem. Phys., 17, 14727–14746, https://doi.org/10.5194/acp-17-14727-2017, https://doi.org/10.5194/acp-17-14727-2017, 2017
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This study introduces and explores the concept of gamma phase space. This space is able to represent all possible variations in the cloud droplet size distributions (DSDs). The methodology was applied to recent in situ aircraft measurements over the Amazon. It is shown that the phase space is able to represent several processes occurring in the clouds in a simple manner. The consequences for cloud studies, modeling, and the representation of the transition from warm to mixed phase are discussed.
Ramon Campos Braga, Daniel Rosenfeld, Ralf Weigel, Tina Jurkat, Meinrat O. Andreae, Manfred Wendisch, Ulrich Pöschl, Christiane Voigt, Christoph Mahnke, Stephan Borrmann, Rachel I. Albrecht, Sergej Molleker, Daniel A. Vila, Luiz A. T. Machado, and Lucas Grulich
Atmos. Chem. Phys., 17, 14433–14456, https://doi.org/10.5194/acp-17-14433-2017, https://doi.org/10.5194/acp-17-14433-2017, 2017
Franziska Köllner, Johannes Schneider, Megan D. Willis, Thomas Klimach, Frank Helleis, Heiko Bozem, Daniel Kunkel, Peter Hoor, Julia Burkart, W. Richard Leaitch, Amir A. Aliabadi, Jonathan P. D. Abbatt, Andreas B. Herber, and Stephan Borrmann
Atmos. Chem. Phys., 17, 13747–13766, https://doi.org/10.5194/acp-17-13747-2017, https://doi.org/10.5194/acp-17-13747-2017, 2017
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We conducted aircraft-based single particle chemical composition measurements in the Canadian high Arctic during summer. Our results provide evidence for a marine-biogenic influence on secondary formation of particulate trimethylamine in the Arctic boundary layer. Understanding emission sources and further processes controlling aerosol number concentration and chemical composition in the pristine Arctic summer is crucial for modeling future climate in the area.
Katharina Schütze, James Charles Wilson, Stephan Weinbruch, Nathalie Benker, Martin Ebert, Gebhard Günther, Ralf Weigel, and Stephan Borrmann
Atmos. Chem. Phys., 17, 12475–12493, https://doi.org/10.5194/acp-17-12475-2017, https://doi.org/10.5194/acp-17-12475-2017, 2017
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Stratospheric particles were collected in the polar stratosphere in winter 1999/2000. Besides the well-studied volatile particles from that region, the main findings of this study are stable carbonaceous particles in the sub-micrometer size range. In addition to carbon, many particles show the elements Si, Fe, Cr and Ni to a minor amount. Based on exclusion, carbonaceous material from IDPs and residues from meteoric ablation and fragmentation remain as the most probable sources.
Marcus Klingebiel, André Ehrlich, Fanny Finger, Timo Röschenthaler, Suad Jakirlić, Matthias Voigt, Stefan Müller, Rolf Maser, Manfred Wendisch, Peter Hoor, Peter Spichtinger, and Stephan Borrmann
Atmos. Meas. Tech., 10, 3485–3498, https://doi.org/10.5194/amt-10-3485-2017, https://doi.org/10.5194/amt-10-3485-2017, 2017
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Microphysical and radiation measurements were collected with the unique AIRcraft TOwed Sensor Shuttle (AIRTOSS) – Learjet tandem platform. It is a combination of a Learjet 35A research aircraft and an instrumented aerodynamic bird, which can be detached from and retracted back to the aircraft during flight.
AIRTOSS and Learjet are equipped with radiative, cloud microphysical, trace gas,
and meteorological instruments to study cirrus clouds.
Micael A. Cecchini, Luiz A. T. Machado, Meinrat O. Andreae, Scot T. Martin, Rachel I. Albrecht, Paulo Artaxo, Henrique M. J. Barbosa, Stephan Borrmann, Daniel Fütterer, Tina Jurkat, Christoph Mahnke, Andreas Minikin, Sergej Molleker, Mira L. Pöhlker, Ulrich Pöschl, Daniel Rosenfeld, Christiane Voigt, Bernadett Weinzierl, and Manfred Wendisch
Atmos. Chem. Phys., 17, 10037–10050, https://doi.org/10.5194/acp-17-10037-2017, https://doi.org/10.5194/acp-17-10037-2017, 2017
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We study the effects of aerosol particles and updraft speed on the warm phase of Amazonian clouds. We expand the sensitivity analysis usually found in the literature by concomitantly considering cloud evolution and the effects on droplet size distribution (DSD) shape. The quantitative results show that particle concentration is the primary driver for the vertical profiles of effective diameter and droplet concentration in the warm phase of Amazonian convective clouds.
Alexander Jost, Miklós Szakáll, Karoline Diehl, Subir K. Mitra, and Stephan Borrmann
Atmos. Chem. Phys., 17, 9717–9732, https://doi.org/10.5194/acp-17-9717-2017, https://doi.org/10.5194/acp-17-9717-2017, 2017
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During riming of graupel and hail, soluble chemical trace constituents contained in the liquid droplets could be retained while freezing onto the glaciated particle, or released back to the air potentially at other altitudes as retained. Quantification of retention constitutes a major uncertainty in numerical models for atmospheric chemistry and improvements hinge upon experimental determination of retention for carboxylic acids, aldehydes, SO2, H2O2, NH2, and others, as presented in this paper.
Ramon Campos Braga, Daniel Rosenfeld, Ralf Weigel, Tina Jurkat, Meinrat O. Andreae, Manfred Wendisch, Mira L. Pöhlker, Thomas Klimach, Ulrich Pöschl, Christopher Pöhlker, Christiane Voigt, Christoph Mahnke, Stephan Borrmann, Rachel I. Albrecht, Sergej Molleker, Daniel A. Vila, Luiz A. T. Machado, and Paulo Artaxo
Atmos. Chem. Phys., 17, 7365–7386, https://doi.org/10.5194/acp-17-7365-2017, https://doi.org/10.5194/acp-17-7365-2017, 2017
Johannes R. W. Fachinger, Stéphane J. Gallavardin, Frank Helleis, Friederike Fachinger, Frank Drewnick, and Stephan Borrmann
Atmos. Meas. Tech., 10, 1623–1637, https://doi.org/10.5194/amt-10-1623-2017, https://doi.org/10.5194/amt-10-1623-2017, 2017
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The design of an ion trap aerosol mass spectrometer was improved, allowing for the instrument's first field deployment. Detection limits were found to be sufficiently low for ambient measurements. Via MS-MS measurements the instrument is capable of differentiating ion fragments of different elemental compositions, but also fragments which only differ in their molecular structures. This could allow for e.g. the differentiation between sugars and carboxylic acids by MS–MS studies on m/z 60 and 73.
Ulrich Schumann, Christoph Kiemle, Hans Schlager, Ralf Weigel, Stephan Borrmann, Francesco D'Amato, Martina Krämer, Renaud Matthey, Alain Protat, Christiane Voigt, and C. Michael Volk
Atmos. Chem. Phys., 17, 2311–2346, https://doi.org/10.5194/acp-17-2311-2017, https://doi.org/10.5194/acp-17-2311-2017, 2017
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A long-lived (1 h) contrail and overshooting convection were observed in the tropics, near Darwin, Australia. The data are used to study the contrail life cycle at low temperatures and cirrus from deep overturning convection in the lower tropical stratosphere. Airborne in situ, lidar, profiler, radar, and satellite data, as well as a photo, are used to distinguish contrail cirrus from convective cirrus and to study the origin of the observed ice and aerosol, up to 2.3 km above the tropopause.
Johannes Schneider, Stephan Mertes, Dominik van Pinxteren, Hartmut Herrmann, and Stephan Borrmann
Atmos. Chem. Phys., 17, 1571–1593, https://doi.org/10.5194/acp-17-1571-2017, https://doi.org/10.5194/acp-17-1571-2017, 2017
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We analyzed the composition of cloud droplet residuals and of aerosol particles sampled on a mountaintop site. The data show that about 85 % of the submicron aerosol mass partitions into the cloud phase, and that the uptake of soluble compounds (nitric acid, ammonia, and organic gases) from the gas phase into the cloud droplets is very effective. This will lead to a redistribution of these compounds among the aerosol particles and thereby to a more uniform aerosol after cloud evaporation.
Susan Schmidt, Johannes Schneider, Thomas Klimach, Stephan Mertes, Ludwig Paul Schenk, Piotr Kupiszewski, Joachim Curtius, and Stephan Borrmann
Atmos. Chem. Phys., 17, 575–594, https://doi.org/10.5194/acp-17-575-2017, https://doi.org/10.5194/acp-17-575-2017, 2017
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Ice formation in clouds is an important process in the formation of precipitation, especially at midlatitudes, but the exact properties of the aerosol particles that initiate freezing is not fully understood. We analysed residual particles from ice crystals sampled from mixed phase clouds. The results show that the residues contain a larger relative amount of soil dust and minerals, but also particles from industrial emissions and lead-containing particles, than the out-of-cloud aerosol.
Caroline Struckmeier, Frank Drewnick, Friederike Fachinger, Gian Paolo Gobbi, and Stephan Borrmann
Atmos. Chem. Phys., 16, 15277–15299, https://doi.org/10.5194/acp-16-15277-2016, https://doi.org/10.5194/acp-16-15277-2016, 2016
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The characteristics of ambient aerosol during two seasons (spring/autumn) and at two locations (suburban/urban) in Rome were investigated. We distinguished regionally advected and locally produced organic aerosols, including from cooking, traffic and biomass burning, but also from locally emitted cigarette smoke, for which we propose a new marker peak for identification in aerosol mass spectra. The impact of Saharan dust advection events on local aerosol concentration was studied.
Gavin J. Phillips, Jim Thieser, Mingjin Tang, Nicolas Sobanski, Gerhard Schuster, Johannes Fachinger, Frank Drewnick, Stephan Borrmann, Heinz Bingemer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 16, 13231–13249, https://doi.org/10.5194/acp-16-13231-2016, https://doi.org/10.5194/acp-16-13231-2016, 2016
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We use trace gas measurements (N2O5, ClNO2, NO3) and particle properties (surface area, nitrate content etc.) to derive uptake coefficients (the probability of removal from the gas-phase on a per-collision basis) for the interaction of N2O5 with ambient aerosol and also the efficiency of formation of ClNO2. The uptake coefficients show high variability but are reasonably well captured by parameterisations based on laboratory measurements.
Ralf Weigel, Peter Spichtinger, Christoph Mahnke, Marcus Klingebiel, Armin Afchine, Andreas Petzold, Martina Krämer, Anja Costa, Sergej Molleker, Philipp Reutter, Miklós Szakáll, Max Port, Lucas Grulich, Tina Jurkat, Andreas Minikin, and Stephan Borrmann
Atmos. Meas. Tech., 9, 5135–5162, https://doi.org/10.5194/amt-9-5135-2016, https://doi.org/10.5194/amt-9-5135-2016, 2016
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The subject of our study concerns measurements with optical array probes (OAPs) on fast-flying aircraft such as the G550 (HALO or HIAPER). At up to Mach 0.7 the effect of air compression upstream of underwing-mounted instruments and particles' inertia need consideration for determining ambient particle concentrations. Compared to conventional practices the introduced correction procedure eliminates ambiguities and exhibits consistency over flight speeds between 50 and 250 m s−.
Wolfgang Woiwode, Michael Höpfner, Lei Bi, Michael C. Pitts, Lamont R. Poole, Hermann Oelhaf, Sergej Molleker, Stephan Borrmann, Marcus Klingebiel, Gennady Belyaev, Andreas Ebersoldt, Sabine Griessbach, Jens-Uwe Grooß, Thomas Gulde, Martina Krämer, Guido Maucher, Christof Piesch, Christian Rolf, Christian Sartorius, Reinhold Spang, and Johannes Orphal
Atmos. Chem. Phys., 16, 9505–9532, https://doi.org/10.5194/acp-16-9505-2016, https://doi.org/10.5194/acp-16-9505-2016, 2016
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The analysis of spectral signatures of a polar stratospheric cloud in airborne infrared remote sensing observations in the Arctic in combination with further collocated measurements supports the view that the observed cloud consisted of highly aspherical nitric acid trihydrate particles. A characteristic "shoulder-like" spectral signature may be exploited for identification of large, highly aspherical nitric acid trihydrate particles involved in denitrification of the polar winter stratosphere.
Martin Ebert, Ralf Weigel, Konrad Kandler, Gebhard Günther, Sergej Molleker, Jens-Uwe Grooß, Bärbel Vogel, Stephan Weinbruch, and Stephan Borrmann
Atmos. Chem. Phys., 16, 8405–8421, https://doi.org/10.5194/acp-16-8405-2016, https://doi.org/10.5194/acp-16-8405-2016, 2016
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Stratospheric aerosol particles were collected within the arctic vortex in late winter. The chemical composition of refractory particles were analyzed by scanning electron microscopy. More than 750 refractory particles with diameters above 500 nm were found consisting of silicates, Fe- and Ca-rich particles and metal mixtures. The detection of refractory particles in the late winter polar stratosphere has strong implications for the formation of polar stratospheric clouds and ozone depletion.
Fanny Finger, Frank Werner, Marcus Klingebiel, André Ehrlich, Evelyn Jäkel, Matthias Voigt, Stephan Borrmann, Peter Spichtinger, and Manfred Wendisch
Atmos. Chem. Phys., 16, 7681–7693, https://doi.org/10.5194/acp-16-7681-2016, https://doi.org/10.5194/acp-16-7681-2016, 2016
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Solar spectra of optical layer properties of cirrus have been derived from the first truly collocated airborne radiation measurements using an aircraft and a towed sensor platform. The measured layer properties differ slightly due to horizontal cirrus inhomogeneities and the influence of low-level water clouds. Applying a 1-D radiative transfer model sensitivity studies were performed. It was found that if a low-level cloud is not considered, the solar cooling of the cirrus is strongly overestimated.
Martina Krämer, Christian Rolf, Anna Luebke, Armin Afchine, Nicole Spelten, Anja Costa, Jessica Meyer, Martin Zöger, Jessica Smith, Robert L. Herman, Bernhard Buchholz, Volker Ebert, Darrel Baumgardner, Stephan Borrmann, Marcus Klingebiel, and Linnea Avallone
Atmos. Chem. Phys., 16, 3463–3483, https://doi.org/10.5194/acp-16-3463-2016, https://doi.org/10.5194/acp-16-3463-2016, 2016
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A guide to cirrus clouds is compiled from extensive model simulations and aircraft observations. Two types of cirrus are found: rather thin in situ cirrus that form directly as ice and thicker liquid origin cirrus consisting of uplifted frozen liquid drops. Over Europe, thinner in situ and liquid origin cirrus occur often together with frontal systems, while over the US and the Tropics, thick liquid origin cirrus formed in large convective systems are detected more frequently.
A. Roth, J. Schneider, T. Klimach, S. Mertes, D. van Pinxteren, H. Herrmann, and S. Borrmann
Atmos. Chem. Phys., 16, 505–524, https://doi.org/10.5194/acp-16-505-2016, https://doi.org/10.5194/acp-16-505-2016, 2016
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This paper reports on single-particle measurements of ambient aerosol particles and cloud residues sampled from orographic clouds on a mountain site in central Germany.
The results show that soot particles can get efficiently activated in cloud droplets when they are mixed with or coated by sulfate and nitrate. Cloud processing leads to addition of nitrate and sulfate to the particles, thereby increasing the hygroscopicity of these particles when they remain in the air after cloud evaporation.
K. Diehl and S. K. Mitra
Atmos. Chem. Phys., 15, 12741–12763, https://doi.org/10.5194/acp-15-12741-2015, https://doi.org/10.5194/acp-15-12741-2015, 2015
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In mid-latitudes, the major fraction of precipitation is initiated via the ice phase. Cloud model simulations estimated the role of aerosol particle types and heterogeneous freezing modes on the ice phase. The results show that the formation of mixed-phase and ice clouds is promoted by the immersion freezing mode, broad drop size spectra containing small as well as large drops, insoluble particles composed by bacteria, feldspar, and illite, and temperatures below -25°C.
F. Drewnick, J.-M. Diesch, P. Faber, and S. Borrmann
Atmos. Meas. Tech., 8, 3811–3830, https://doi.org/10.5194/amt-8-3811-2015, https://doi.org/10.5194/amt-8-3811-2015, 2015
M. Beekmann, A. S. H. Prévôt, F. Drewnick, J. Sciare, S. N. Pandis, H. A. C. Denier van der Gon, M. Crippa, F. Freutel, L. Poulain, V. Ghersi, E. Rodriguez, S. Beirle, P. Zotter, S.-L. von der Weiden-Reinmüller, M. Bressi, C. Fountoukis, H. Petetin, S. Szidat, J. Schneider, A. Rosso, I. El Haddad, A. Megaritis, Q. J. Zhang, V. Michoud, J. G. Slowik, S. Moukhtar, P. Kolmonen, A. Stohl, S. Eckhardt, A. Borbon, V. Gros, N. Marchand, J. L. Jaffrezo, A. Schwarzenboeck, A. Colomb, A. Wiedensohler, S. Borrmann, M. Lawrence, A. Baklanov, and U. Baltensperger
Atmos. Chem. Phys., 15, 9577–9591, https://doi.org/10.5194/acp-15-9577-2015, https://doi.org/10.5194/acp-15-9577-2015, 2015
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A detailed characterization of air quality in the Paris (France) agglomeration, a megacity, during two summer and winter intensive campaigns and from additional 1-year observations, revealed that about 70% of the fine particulate matter (PM) at urban background is transported into the megacity from upwind regions. Unexpectedly, a major part of organic PM is of modern origin (woodburning and cooking activities, secondary formation from biogenic VOC).
S. Schmidt, J. Schneider, T. Klimach, S. Mertes, L. P. Schenk, J. Curtius, P. Kupiszewski, E. Hammer, P. Vochezer, G. Lloyd, M. Ebert, K. Kandler, S. Weinbruch, and S. Borrmann
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-4677-2015, https://doi.org/10.5194/acpd-15-4677-2015, 2015
Revised manuscript not accepted
M. Klingebiel, A. de Lozar, S. Molleker, R. Weigel, A. Roth, L. Schmidt, J. Meyer, A. Ehrlich, R. Neuber, M. Wendisch, and S. Borrmann
Atmos. Chem. Phys., 15, 617–631, https://doi.org/10.5194/acp-15-617-2015, https://doi.org/10.5194/acp-15-617-2015, 2015
W. Frey, S. Borrmann, F. Fierli, R. Weigel, V. Mitev, R. Matthey, F. Ravegnani, N. M. Sitnikov, A. Ulanovsky, and F. Cairo
Atmos. Chem. Phys., 14, 13223–13240, https://doi.org/10.5194/acp-14-13223-2014, https://doi.org/10.5194/acp-14-13223-2014, 2014
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This study presents in situ cloud microphysical observations obtained during a double flight in a Hector thunderstorm during the SCOUT-O3 campaign from Darwin, Northern Australia, in 2005. The measurements show a change of the micophysics with the storm's evolution. The clouds in the dissipating stage possess a high potential for affecting the humidity in the tropical tropopause layer.
K. Diehl, M. Debertshäuser, O. Eppers, H. Schmithüsen, S. K. Mitra, and S. Borrmann
Atmos. Chem. Phys., 14, 12343–12355, https://doi.org/10.5194/acp-14-12343-2014, https://doi.org/10.5194/acp-14-12343-2014, 2014
W. Woiwode, J.-U. Grooß, H. Oelhaf, S. Molleker, S. Borrmann, A. Ebersoldt, W. Frey, T. Gulde, S. Khaykin, G. Maucher, C. Piesch, and J. Orphal
Atmos. Chem. Phys., 14, 11525–11544, https://doi.org/10.5194/acp-14-11525-2014, https://doi.org/10.5194/acp-14-11525-2014, 2014
S. Molleker, S. Borrmann, H. Schlager, B. Luo, W. Frey, M. Klingebiel, R. Weigel, M. Ebert, V. Mitev, R. Matthey, W. Woiwode, H. Oelhaf, A. Dörnbrack, G. Stratmann, J.-U. Grooß, G. Günther, B. Vogel, R. Müller, M. Krämer, J. Meyer, and F. Cairo
Atmos. Chem. Phys., 14, 10785–10801, https://doi.org/10.5194/acp-14-10785-2014, https://doi.org/10.5194/acp-14-10785-2014, 2014
F. Freutel, F. Drewnick, J. Schneider, T. Klimach, and S. Borrmann
Atmos. Meas. Tech., 6, 3131–3145, https://doi.org/10.5194/amt-6-3131-2013, https://doi.org/10.5194/amt-6-3131-2013, 2013
M. von Hobe, S. Bekki, S. Borrmann, F. Cairo, F. D'Amato, G. Di Donfrancesco, A. Dörnbrack, A. Ebersoldt, M. Ebert, C. Emde, I. Engel, M. Ern, W. Frey, S. Genco, S. Griessbach, J.-U. Grooß, T. Gulde, G. Günther, E. Hösen, L. Hoffmann, V. Homonnai, C. R. Hoyle, I. S. A. Isaksen, D. R. Jackson, I. M. Jánosi, R. L. Jones, K. Kandler, C. Kalicinsky, A. Keil, S. M. Khaykin, F. Khosrawi, R. Kivi, J. Kuttippurath, J. C. Laube, F. Lefèvre, R. Lehmann, S. Ludmann, B. P. Luo, M. Marchand, J. Meyer, V. Mitev, S. Molleker, R. Müller, H. Oelhaf, F. Olschewski, Y. Orsolini, T. Peter, K. Pfeilsticker, C. Piesch, M. C. Pitts, L. R. Poole, F. D. Pope, F. Ravegnani, M. Rex, M. Riese, T. Röckmann, B. Rognerud, A. Roiger, C. Rolf, M. L. Santee, M. Scheibe, C. Schiller, H. Schlager, M. Siciliani de Cumis, N. Sitnikov, O. A. Søvde, R. Spang, N. Spelten, F. Stordal, O. Sumińska-Ebersoldt, A. Ulanovski, J. Ungermann, S. Viciani, C. M. Volk, M. vom Scheidt, P. von der Gathen, K. Walker, T. Wegner, R. Weigel, S. Weinbruch, G. Wetzel, F. G. Wienhold, I. Wohltmann, W. Woiwode, I. A. K. Young, V. Yushkov, B. Zobrist, and F. Stroh
Atmos. Chem. Phys., 13, 9233–9268, https://doi.org/10.5194/acp-13-9233-2013, https://doi.org/10.5194/acp-13-9233-2013, 2013
M. Crippa, P. F. DeCarlo, J. G. Slowik, C. Mohr, M. F. Heringa, R. Chirico, L. Poulain, F. Freutel, J. Sciare, J. Cozic, C. F. Di Marco, M. Elsasser, J. B. Nicolas, N. Marchand, E. Abidi, A. Wiedensohler, F. Drewnick, J. Schneider, S. Borrmann, E. Nemitz, R. Zimmermann, J.-L. Jaffrezo, A. S. H. Prévôt, and U. Baltensperger
Atmos. Chem. Phys., 13, 961–981, https://doi.org/10.5194/acp-13-961-2013, https://doi.org/10.5194/acp-13-961-2013, 2013
F. Freutel, J. Schneider, F. Drewnick, S.-L. von der Weiden-Reinmüller, M. Crippa, A. S. H. Prévôt, U. Baltensperger, L. Poulain, A. Wiedensohler, J. Sciare, R. Sarda-Estève, J. F. Burkhart, S. Eckhardt, A. Stohl, V. Gros, A. Colomb, V. Michoud, J. F. Doussin, A. Borbon, M. Haeffelin, Y. Morille, M. Beekmann, and S. Borrmann
Atmos. Chem. Phys., 13, 933–959, https://doi.org/10.5194/acp-13-933-2013, https://doi.org/10.5194/acp-13-933-2013, 2013
Related subject area
Subject: Clouds and Precipitation | Research Activity: Laboratory Studies | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Stable and unstable fall motions of plate-like ice crystal analogues
Secondary ice production – no evidence of efficient rime-splintering mechanism
Fragmentation of ice particles: laboratory experiments on graupel–graupel and graupel–snowflake collisions
Molecular simulations reveal that heterogeneous ice nucleation occurs at higher temperatures in water under capillary tension
Measurement of the collision rate coefficients between atmospheric ions and multiply charged aerosol particles in the CERN CLOUD chamber
Re-evaluating cloud chamber constraints on depositional ice growth in cirrus clouds – Part 1: Model description and sensitivity tests
Ice nucleation by smectites: the role of the edges
A single-parameter hygroscopicity model for functionalized insoluble aerosol surfaces
Mexican agricultural soil dust as a source of ice nucleating particles
The impact of (bio-)organic substances on the ice nucleation activity of the K-feldspar microcline in aqueous solutions
Secondary ice production during the break-up of freezing water drops on impact with ice particles
High homogeneous freezing onsets of sulfuric acid aerosol at cirrus temperatures
Laboratory and field studies of ice-nucleating particles from open-lot livestock facilities in Texas
Comment on “Review of experimental studies of secondary ice production” by Korolev and Leisner (2020)
Effect of chemically induced fracturing on the ice nucleation activity of alkali feldspar
Ice nucleation ability of ammonium sulfate aerosol particles internally mixed with secondary organics
Ice-nucleating particles in precipitation samples from the Texas Panhandle
Comparative study on immersion freezing utilizing single-droplet levitation methods
Exploratory experiments on pre-activated freezing nucleation on mercuric iodide
Review of experimental studies of secondary ice production
The role of contact angle and pore width on pore condensation and freezing
Technical note: Equilibrium droplet size distributions in a turbulent cloud chamber with uniform supersaturation
Protein aggregates nucleate ice: the example of apoferritin
No anomalous supersaturation in ultracold cirrus laboratory experiments
Lateral facet growth of ice and snow – Part 1: Observations and applications to secondary habits
The ice-nucleating ability of quartz immersed in water and its atmospheric importance compared to K-feldspar
Ice nucleation properties of K-feldspar polymorphs and plagioclase feldspars
Enhanced ice nucleation activity of coal fly ash aerosol particles initiated by ice-filled pores
A comprehensive characterization of ice nucleation by three different types of cellulose particles immersed in water
Activation of intact bacteria and bacterial fragments mixed with agar as cloud droplets and ice crystals in cloud chamber experiments
Anomalous holiday precipitation over southern China
Coal fly ash: linking immersion freezing behavior and physicochemical particle properties
Surface roughness during depositional growth and sublimation of ice crystals
Ice nucleation abilities of soot particles determined with the Horizontal Ice Nucleation Chamber
The efficiency of secondary organic aerosol particles acting as ice-nucleating particles under mixed-phase cloud conditions
Uncertainty in counting ice nucleating particles with continuous flow diffusion chambers
Experimental evidence of the rear capture of aerosol particles by raindrops
Refreeze experiments with water droplets containing different types of ice nuclei interpreted by classical nucleation theory
Pre-activation of aerosol particles by ice preserved in pores
Heterogeneous ice nucleation on dust particles sourced from nine deserts worldwide – Part 1: Immersion freezing
A comparative study of K-rich and Na/Ca-rich feldspar ice-nucleating particles in a nanoliter droplet freezing assay
Ice nucleation efficiency of AgI: review and new insights
The adsorption of fungal ice-nucleating proteins on mineral dusts: a terrestrial reservoir of atmospheric ice-nucleating particles
Exploring an approximation for the homogeneous freezing temperature of water droplets
Cloud chamber experiments on the origin of ice crystal complexity in cirrus clouds
Phase transition observations and discrimination of small cloud particles by light polarization in expansion chamber experiments
Analysis of isothermal and cooling-rate-dependent immersion freezing by a unifying stochastic ice nucleation model
Pre-activation of ice-nucleating particles by the pore condensation and freezing mechanism
Influence of the ambient humidity on the concentration of natural deposition-mode ice-nucleating particles
Comparison of measured and calculated collision efficiencies at low temperatures
Jennifer R. Stout, Christopher D. Westbrook, Thorwald H. M. Stein, and Mark W. McCorquodale
Atmos. Chem. Phys., 24, 11133–11155, https://doi.org/10.5194/acp-24-11133-2024, https://doi.org/10.5194/acp-24-11133-2024, 2024
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This study uses 3D-printed ice crystal analogues falling in a water–glycerine mix and observed with multi-view cameras, simulating atmospheric conditions. Four types of motion are observed: stable, zigzag, transitional, and spiralling. Particle shape strongly influences motion; complex shapes have a wider range of conditions where they fall steadily compared to simple plates. The most common orientation of unstable particles is non-horizontal, contrary to prior assumptions of always horizontal.
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.
Pierre Grzegorczyk, Sudha Yadav, Florian Zanger, Alexander Theis, Subir K. Mitra, Stephan Borrmann, and Miklós Szakáll
Atmos. Chem. Phys., 23, 13505–13521, https://doi.org/10.5194/acp-23-13505-2023, https://doi.org/10.5194/acp-23-13505-2023, 2023
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Secondary ice production generates high concentrations of ice crystals in clouds. These processes have been poorly understood. We conducted experiments at the wind tunnel laboratory of the Johannes Gutenberg University, Mainz, on graupel–graupel and graupel–snowflake collisions. From these experiments fragment number, size, cross-sectional area, and aspect ratio were determined.
Elise Rosky, Will Cantrell, Tianshu Li, Issei Nakamura, and Raymond A. Shaw
Atmos. Chem. Phys., 23, 10625–10642, https://doi.org/10.5194/acp-23-10625-2023, https://doi.org/10.5194/acp-23-10625-2023, 2023
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Using computer simulations of water, we find that water under tension freezes more easily than under normal conditions. A linear equation describes how freezing temperature increases with tension. Accordingly, simulations show that naturally occurring tension in water capillary bridges leads to higher freezing temperatures. This work is an early step in determining if atmospheric cloud droplets freeze due to naturally occurring tension, for example, during processes such as droplet collisions.
Joschka Pfeifer, Naser G. A. Mahfouz, Benjamin C. Schulze, Serge Mathot, Dominik Stolzenburg, Rima Baalbaki, Zoé Brasseur, Lucia Caudillo, Lubna Dada, Manuel Granzin, Xu-Cheng He, Houssni Lamkaddam, Brandon Lopez, Vladimir Makhmutov, Ruby Marten, Bernhard Mentler, Tatjana Müller, Antti Onnela, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Meredith Schervish, Ping Tian, Nsikanabasi S. Umo, Dongyu S. Wang, Mingyi Wang, Stefan K. Weber, André Welti, Yusheng Wu, Marcel Zauner-Wieczorek, Antonio Amorim, Imad El Haddad, Markku Kulmala, Katrianne Lehtipalo, Tuukka Petäjä, António Tomé, Sander Mirme, Hanna E. Manninen, Neil M. Donahue, Richard C. Flagan, Andreas Kürten, Joachim Curtius, and Jasper Kirkby
Atmos. Chem. Phys., 23, 6703–6718, https://doi.org/10.5194/acp-23-6703-2023, https://doi.org/10.5194/acp-23-6703-2023, 2023
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Attachment rate coefficients between ions and charged aerosol particles determine their lifetimes and may also influence cloud dynamics and aerosol processing. Here we present novel experiments that measure ion–aerosol attachment rate coefficients for multiply charged aerosol particles under atmospheric conditions in the CERN CLOUD chamber. Our results provide experimental discrimination between various theoretical models.
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.
Anand Kumar, Kristian Klumpp, Chen Barak, Giora Rytwo, Michael Plötze, Thomas Peter, and Claudia Marcolli
Atmos. Chem. Phys., 23, 4881–4902, https://doi.org/10.5194/acp-23-4881-2023, https://doi.org/10.5194/acp-23-4881-2023, 2023
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Smectites are a major class of clay minerals that are ice nucleation (IN) active. They form platelets that swell or even delaminate in water by intercalation of water between their layers. We hypothesize that at least three smectite layers need to be stacked together to host a critical ice embryo on clay mineral edges and that the larger the surface edge area is, the higher the freezing temperature. Edge sites on such clay particles play a crucial role in imparting IN ability to such particles.
Chun-Ning Mao, Kanishk Gohil, and Akua A. Asa-Awuku
Atmos. Chem. Phys., 22, 13219–13228, https://doi.org/10.5194/acp-22-13219-2022, https://doi.org/10.5194/acp-22-13219-2022, 2022
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The impact of molecular-level surface chemistry for aerosol water uptake and droplet growth is not well understood. In this work we show changes in water uptake due to molecular-level surface chemistry can be measured and quantified. In addition, we develop a single-parameter model, representing changes in aerosol chemistry that can be used in global climate models to reduce the uncertainty in aerosol-cloud predictions.
Diana L. Pereira, Irma Gavilán, Consuelo Letechipía, Graciela B. Raga, Teresa Pi Puig, Violeta Mugica-Álvarez, Harry Alvarez-Ospina, Irma Rosas, Leticia Martinez, Eva Salinas, Erika T. Quintana, Daniel Rosas, and Luis A. Ladino
Atmos. Chem. Phys., 22, 6435–6447, https://doi.org/10.5194/acp-22-6435-2022, https://doi.org/10.5194/acp-22-6435-2022, 2022
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Airborne particles were i) collected in an agricultural fields and ii) generated in the laboratory from agricultural soil samples to analyze their ice nucleating abilities. It was found that the size and chemical composition of the Mexican agricultural dust particles influence their ice nucleating behavior, where the organic components are likely responsible for their efficiency as INPs. The INP concentrations from the present study are comparable to those from higher latitudes.
Kristian Klumpp, Claudia Marcolli, and Thomas Peter
Atmos. Chem. Phys., 22, 3655–3673, https://doi.org/10.5194/acp-22-3655-2022, https://doi.org/10.5194/acp-22-3655-2022, 2022
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Surface interactions with solutes can significantly alter the ice nucleation activity of mineral dust. Past studies revealed the sensitivity of microcline, one of the most ice-active types of dust in the atmosphere, to inorganic solutes. This study focuses on the interaction of microcline with bio-organic substances and the resulting effects on its ice nucleation activity. We observe strongly hampered ice nucleation activity due to the presence of carboxylic and amino acids but not for polyols.
Rachel L. James, Vaughan T. J. Phillips, and Paul J. Connolly
Atmos. Chem. Phys., 21, 18519–18530, https://doi.org/10.5194/acp-21-18519-2021, https://doi.org/10.5194/acp-21-18519-2021, 2021
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Secondary ice production (SIP) plays an important role in ice formation within mixed-phase clouds. We present a laboratory investigation of a potentially new SIP mechanism involving the collisions of supercooled water drops with ice particles. At impact, the supercooled water drop fragments form smaller secondary drops. Approximately 30 % of the secondary drops formed during the retraction phase of the supercooled water drop impact freeze over a temperature range of −4 °C to −12 °C.
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.
Vaughan T. J. Phillips, Jun-Ichi Yano, Akash Deshmukh, and Deepak Waman
Atmos. Chem. Phys., 21, 11941–11953, https://doi.org/10.5194/acp-21-11941-2021, https://doi.org/10.5194/acp-21-11941-2021, 2021
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For decades, high concentrations of ice observed in precipitating mixed-phase clouds have created an enigma. Such concentrations are higher than can be explained by the action of aerosols or by the spontaneous freezing of most cloud droplets. The controversy has partly persisted due to the lack of laboratory experimentation in ice microphysics, especially regarding fragmentation of ice, a topic reviewed by a recent paper. Our comment attempts to clarify some issues with regards to that review.
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.
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.
Miklós Szakáll, Michael Debertshäuser, Christian Philipp Lackner, Amelie Mayer, Oliver Eppers, Karoline Diehl, Alexander Theis, Subir Kumar Mitra, and Stephan Borrmann
Atmos. Chem. Phys., 21, 3289–3316, https://doi.org/10.5194/acp-21-3289-2021, https://doi.org/10.5194/acp-21-3289-2021, 2021
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The freezing of cloud drops is promoted by ice-nucleating particles immersed in the drops. This process is essential to understand ice and subsequent precipitation formation in clouds. We investigated the efficiency of several particle types to trigger immersion freezing with two single-drop levitation techniques: a wind tunnel and an acoustic levitator. The evaluation accounted for different conditions during our two series of experiments, which is also applicable to future comparison studies.
Gabor Vali
Atmos. Chem. Phys., 21, 2551–2568, https://doi.org/10.5194/acp-21-2551-2021, https://doi.org/10.5194/acp-21-2551-2021, 2021
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The freezing of water drops in clouds is a prime example for the role of ice-nucleating particles (INPs). Mercuric iodide particles and a few other substances can be conditioned to become very effective INPs after previous ice formation and moderate heating to melt temperatures, opening a new pathway to ice formation in the atmosphere and in other systems like tissue preservation, artificial snow making, and more.
Alexei Korolev and Thomas Leisner
Atmos. Chem. Phys., 20, 11767–11797, https://doi.org/10.5194/acp-20-11767-2020, https://doi.org/10.5194/acp-20-11767-2020, 2020
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Secondary ice production (SIP) plays a key role in the formation of ice particles in tropospheric clouds. This work presents a critical review of the laboratory studies related to secondary ice production. It aims to identify gaps in our knowledge of SIP as well as to stimulate further laboratory studies focused on obtaining a quantitative description of efficiencies for each SIP mechanism.
Robert O. David, Jonas Fahrni, Claudia Marcolli, Fabian Mahrt, Dominik Brühwiler, and Zamin A. Kanji
Atmos. Chem. Phys., 20, 9419–9440, https://doi.org/10.5194/acp-20-9419-2020, https://doi.org/10.5194/acp-20-9419-2020, 2020
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Ice crystal formation plays an important role in controlling the Earth's climate. However, the mechanisms responsible for ice formation in the atmosphere are still uncertain. Here we use surrogates for atmospherically relevant porous particles to determine the role of pore diameter and wettability on the ability of porous particles to nucleate ice in the atmosphere. Our results are consistent with the pore condensation and freeing mechanism.
Steven K. Krueger
Atmos. Chem. Phys., 20, 7895–7909, https://doi.org/10.5194/acp-20-7895-2020, https://doi.org/10.5194/acp-20-7895-2020, 2020
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When CCN are injected into a turbulent cloud chamber at a constant rate, and the rate of droplet activation is balanced by the rate of droplet fallout, a steady-state droplet size distribution (DSD) can be achieved. Analytic DSDs and PDFs of droplet radius were derived for such conditions when there is uniform supersaturation. Given the chamber height, the analytic PDF is determined by the supersaturation alone. This could allow one to infer the supersaturation that produced a measured PDF.
María Cascajo-Castresana, Robert O. David, Maiara A. Iriarte-Alonso, Alexander M. Bittner, and Claudia Marcolli
Atmos. Chem. Phys., 20, 3291–3315, https://doi.org/10.5194/acp-20-3291-2020, https://doi.org/10.5194/acp-20-3291-2020, 2020
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Atmospheric ice-nucleating particles are rare but relevant for cloud glaciation. A source of particles that nucleate ice above −15 °C is biological material including some proteins. Here we show that proteins of very diverse functions and structures can nucleate ice. Among these, the iron storage protein apoferritin stands out, with activity up to −4 °C. We show that its activity does not stem from correctly assembled proteins but from misfolded protein monomers or oligomers and aggregates.
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.
Jon Nelson and Brian D. Swanson
Atmos. Chem. Phys., 19, 15285–15320, https://doi.org/10.5194/acp-19-15285-2019, https://doi.org/10.5194/acp-19-15285-2019, 2019
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Ice crystals in clouds have a wide variety. But many crystal forms are inexplicable using the common approach of modeling the growth rates normal to the crystal faces. Instead of using only this normal-growth approach, we suggest including lateral facet growth processes. Using such lateral processes, backed up by new experiments, we give explanations for some of these puzzling forms. The forms include the center droxtal in stellar crystals, scrolls, capped columns, sheath bundles, and trigonals.
Alexander D. Harrison, Katherine Lever, Alberto Sanchez-Marroquin, Mark A. Holden, Thomas F. Whale, Mark D. Tarn, James B. McQuaid, and Benjamin J. Murray
Atmos. Chem. Phys., 19, 11343–11361, https://doi.org/10.5194/acp-19-11343-2019, https://doi.org/10.5194/acp-19-11343-2019, 2019
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Mineral dusts are a source of ice-nucleating particles (INPs) in the atmosphere. Here we present a comprehensive survey of the ice-nucleating ability of naturally occurring quartz. We show the ice-nucleating variability of quartz and its sensitivity to time spent in water and air. We propose four new parameterizations for the minerals quartz, K feldspar, albite and plagioclase to predict INP concentrations in the atmosphere and show that K-feldspar is the dominant INP type in mineral dusts.
André Welti, Ulrike Lohmann, and Zamin A. Kanji
Atmos. Chem. Phys., 19, 10901–10918, https://doi.org/10.5194/acp-19-10901-2019, https://doi.org/10.5194/acp-19-10901-2019, 2019
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The ice nucleation ability of singly immersed feldspar particles in suspended water droplets relevant for ice crystal formation under mixed-phase cloud conditions is presented. The effects of particle size, crystal structure, trace metal and mineralogical composition are discussed by testing up to five different diameters in the submicron range and nine different feldspar samples at conditions relevant for ice nucleation in mixed-phase clouds.
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.
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.
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.
Jiahui Zhang, Dao-Yi Gong, Rui Mao, Jing Yang, Ziyin Zhang, and Yun Qian
Atmos. Chem. Phys., 18, 16775–16791, https://doi.org/10.5194/acp-18-16775-2018, https://doi.org/10.5194/acp-18-16775-2018, 2018
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The Chinese Spring Festival (also known as the Chinese New Year or Lunar New Year) is the most important festival in China. This paper reports that during the Chinese Spring Festival, the precipitation over southern China has been significantly reduced. The precipitation reduction is due to anomalous northerly winds. We suppose that anomalous atmospheric circulation is likely related to the human activity during holidays. It is an interesting phenomenon.
Sarah Grawe, Stefanie Augustin-Bauditz, Hans-Christian Clemen, Martin Ebert, Stine Eriksen Hammer, Jasmin Lubitz, Naama Reicher, Yinon Rudich, Johannes Schneider, Robert Staacke, Frank Stratmann, André Welti, and Heike Wex
Atmos. Chem. Phys., 18, 13903–13923, https://doi.org/10.5194/acp-18-13903-2018, https://doi.org/10.5194/acp-18-13903-2018, 2018
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In this study, coal fly ash particles immersed in supercooled cloud droplets were analyzed concerning their freezing behavior. Additionally, physico-chemical particle properties (morphology, chemical composition, crystallography) were investigated. In combining both aspects, components that potentially contribute to the observed freezing behavior of the ash could be identified. Interactions at the particle-water interface, that depend on suspension time and influence freezing, are discussed.
Jens Voigtländer, Cedric Chou, Henner Bieligk, Tina Clauss, Susan Hartmann, Paul Herenz, Dennis Niedermeier, Georg Ritter, Frank Stratmann, and Zbigniew Ulanowski
Atmos. Chem. Phys., 18, 13687–13702, https://doi.org/10.5194/acp-18-13687-2018, https://doi.org/10.5194/acp-18-13687-2018, 2018
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Surface roughness of ice crystals has recently been acknowledged to strongly influence the radiative properties of cold clouds such as cirrus, but it is unclear how this roughness arises. The study investigates the origins of ice surface roughness under a variety of atmospherically relevant conditions, using a novel method to measure roughness quantitatively. It is found that faster growth leads to stronger roughness. Roughness also increases following repeated growth–sublimation cycles.
Fabian Mahrt, Claudia Marcolli, Robert O. David, Philippe Grönquist, Eszter J. Barthazy Meier, Ulrike Lohmann, and Zamin A. Kanji
Atmos. Chem. Phys., 18, 13363–13392, https://doi.org/10.5194/acp-18-13363-2018, https://doi.org/10.5194/acp-18-13363-2018, 2018
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The ice nucleation ability of different soot particles in the cirrus and mixed-phase cloud temperature regime is presented. The impact of aerosol particle size, particle morphology, organic matter and hydrophilicity on ice nucleation is examined. We propose ice nucleation proceeds via a pore condensation freezing mechanism for soot particles with the necessary physicochemical properties that nucleated ice well below water saturation.
Wiebke Frey, Dawei Hu, James Dorsey, M. Rami Alfarra, Aki Pajunoja, Annele Virtanen, Paul Connolly, and Gordon McFiggans
Atmos. Chem. Phys., 18, 9393–9409, https://doi.org/10.5194/acp-18-9393-2018, https://doi.org/10.5194/acp-18-9393-2018, 2018
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The coupled system of the Manchester Aerosol Chamber and Manchester Ice Cloud Chamber was used to study the ice-forming abilities of secondary
organic aerosol particles under mixed-phase cloud conditions. Given the vast abundance of secondary organic particles in the atmosphere, they
might present an important contribution to ice-nucleating particles. However, we find that in the studied temperature range (20 to 28 °C)
the secondary organic particles do not nucleate ice particles.
Sarvesh Garimella, Daniel A. Rothenberg, Martin J. Wolf, Robert O. David, Zamin A. Kanji, Chien Wang, Michael Rösch, and Daniel J. Cziczo
Atmos. Chem. Phys., 17, 10855–10864, https://doi.org/10.5194/acp-17-10855-2017, https://doi.org/10.5194/acp-17-10855-2017, 2017
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This study investigates systematic and variable low bias in the measurement of ice nucleating particle concentration using continuous flow diffusion chambers. We find that non-ideal instrument behavior exposes particles to different humidities and/or temperatures than predicted from theory. We use a machine learning approach to quantify and minimize the uncertainty associated with this measurement bias.
Pascal Lemaitre, Arnaud Querel, Marie Monier, Thibault Menard, Emmanuel Porcheron, and Andrea I. Flossmann
Atmos. Chem. Phys., 17, 4159–4176, https://doi.org/10.5194/acp-17-4159-2017, https://doi.org/10.5194/acp-17-4159-2017, 2017
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We present new measurements of the efficiency with which aerosol particles are collected by raindrops. These measurements provide the link to reconcile the scavenging coefficients obtained from theoretical approaches with those from experimental studies. We provide proof of the rear capture that is a fundamental effect on submicroscopic particles. Finally, we propose an expression to take into account this mechanism to calculate the collection efficiency for drops within the rain size range.
Lukas Kaufmann, Claudia Marcolli, Beiping Luo, and Thomas Peter
Atmos. Chem. Phys., 17, 3525–3552, https://doi.org/10.5194/acp-17-3525-2017, https://doi.org/10.5194/acp-17-3525-2017, 2017
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To improve the understanding of heterogeneous ice nucleation, we have subjected different ice nuclei to repeated freezing cycles and evaluated the freezing temperatures with different parameterizations of classical nucleation theory. It was found that two fit parameters were necessary to describe the temperature dependence of the nucleation rate.
Claudia Marcolli
Atmos. Chem. Phys., 17, 1595–1622, https://doi.org/10.5194/acp-17-1595-2017, https://doi.org/10.5194/acp-17-1595-2017, 2017
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Laboratory studies from the last century have shown that some types of particles are susceptible to pre-activation, i.e. they are able to develop macroscopic ice at warmer temperatures or lower relative humidities after they had been involved in an ice nucleation event before. This review analyses these works under the presumption that pre-activation occurs by ice preserved in pores, and it discusses atmospheric scenarios for which pre-activation might be important.
Yvonne Boose, André Welti, James Atkinson, Fabiola Ramelli, Anja Danielczok, Heinz G. Bingemer, Michael Plötze, Berko Sierau, Zamin A. Kanji, and Ulrike Lohmann
Atmos. Chem. Phys., 16, 15075–15095, https://doi.org/10.5194/acp-16-15075-2016, https://doi.org/10.5194/acp-16-15075-2016, 2016
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We compare the immersion freezing behavior of four airborne to 11 surface-collected dust samples to investigate the role of different minerals for atmospheric ice nucleation on desert dust. We find that present K-feldspars dominate at T > 253 K, while quartz does at colder temperatures, and surface-collected dust samples are not necessarily representative for airborne dust. For improved ice cloud prediction, modeling of quartz and feldspar emission and transport are key.
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.
Claudia Marcolli, Baban Nagare, André Welti, and Ulrike Lohmann
Atmos. Chem. Phys., 16, 8915–8937, https://doi.org/10.5194/acp-16-8915-2016, https://doi.org/10.5194/acp-16-8915-2016, 2016
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Silver iodide is one of the best-investigated ice nuclei. It has relevance for the atmosphere since it is used for glaciogenic cloud seeding. Nevertheless, many open questions remain. This paper gives an overview of silver iodide as an ice nucleus and tries to identify the factors that influence the ice nucleation ability of silver iodide.
Daniel O'Sullivan, Benjamin J. Murray, James F. Ross, and Michael E. Webb
Atmos. Chem. Phys., 16, 7879–7887, https://doi.org/10.5194/acp-16-7879-2016, https://doi.org/10.5194/acp-16-7879-2016, 2016
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In the absence of particles which can trigger freezing, cloud droplets can exist in a supercooled liquid state well below the melting point. However, the sources of efficient ice-nucleating particles in the atmosphere are uncertain. Here we show that ice-nucleating proteins produced by soil fungi can bind to clay particles in soils. Hence, the subsequent dispersion of soil particles into the atmosphere acts as a route through which biological ice nucleators can influence clouds.
Kuan-Ting O and Robert Wood
Atmos. Chem. Phys., 16, 7239–7249, https://doi.org/10.5194/acp-16-7239-2016, https://doi.org/10.5194/acp-16-7239-2016, 2016
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In this work, based on the well-known formulae of classical nucleation theory (CNT), the temperature at which the mean number of critical embryos inside a droplet is unity is derived from the Boltzmann distribution function and explored as a new simplified approximation for homogeneous freezing temperature. It thus appears that the simplicity of this approximation makes it potentially useful for predicting homogeneous freezing temperatures of water droplets in the atmosphere.
Martin Schnaiter, Emma Järvinen, Paul Vochezer, Ahmed Abdelmonem, Robert Wagner, Olivier Jourdan, Guillaume Mioche, Valery N. Shcherbakov, Carl G. Schmitt, Ugo Tricoli, Zbigniew Ulanowski, and Andrew J. Heymsfield
Atmos. Chem. Phys., 16, 5091–5110, https://doi.org/10.5194/acp-16-5091-2016, https://doi.org/10.5194/acp-16-5091-2016, 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.
Peter A. Alpert and Daniel A. Knopf
Atmos. Chem. Phys., 16, 2083–2107, https://doi.org/10.5194/acp-16-2083-2016, https://doi.org/10.5194/acp-16-2083-2016, 2016
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A stochastic immersion freezing model is introduced capable of reproducing laboratory data for a variety of experimental methods using a time and surface area dependent ice nucleation process. The assumption that droplets contain identical surface area is evaluated. A quantitative uncertainty analysis of the laboratory observed freezing process is presented. Our results imply that ice nuclei surface area assumptions are crucial for interpretation of experimental immersion freezing results.
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).
M. L. López and E. E. Ávila
Atmos. Chem. Phys., 16, 927–932, https://doi.org/10.5194/acp-16-927-2016, https://doi.org/10.5194/acp-16-927-2016, 2016
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This work deals with the origin and nature of atmospheric ice-nucleating particles (INPs). An accurate determination of the atmospheric INP concentration is relevant since INPs induce freezing in clouds, thus initiating an efficient mechanism for cloud particles to reach a precipitating size.
The effect of relative humidity on the INP concentration at ground level was analyzed and discussed.
B. Nagare, C. Marcolli, O. Stetzer, and U. Lohmann
Atmos. Chem. Phys., 15, 13759–13776, https://doi.org/10.5194/acp-15-13759-2015, https://doi.org/10.5194/acp-15-13759-2015, 2015
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We determined collision efficiencies of cloud droplets with aerosol particles experimentally and found that they were around 1 order of magnitude higher than theoretical formulations that include Brownian diffusion, impaction, interception, thermophoretic, diffusiophoretic and electric forces. This is most probably due to uncertainties and inaccuracies in the theoretical formulations of thermophoretic and diffusiophoretic processes.
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Short summary
The properties of ice crystals smaller than 150 µm in diameter were investigated in a cold-room laboratory using digital holography and microscopy. Automated image processing has been used to determine the track of falling ice crystals, and collected crystals were melted and scanned under a microscope to infer particle mass. A parameterization relating particle size and mass was determined which describes ice crystals in this size range more accurately than existing relationships.
The properties of ice crystals smaller than 150 µm in diameter were investigated in a cold-room...
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