Articles | Volume 22, issue 1
https://doi.org/10.5194/bg-22-103-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-103-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Jan 2025
Research article |
| 09 Jan 2025
| 09 Jan 2025
Aggregation of ice-nucleating macromolecules from Betula pendula pollen determines ice nucleation efficiency
Florian Wieland
Institute of Materials Chemistry, TU Wien, 1060 Vienna, Austria
Multiphase Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
Nadine Bothen
Multiphase Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
Ralph Schwidetzky
Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, 55128 Mainz, Germany
Teresa M. Seifried
Institute of Materials Chemistry, TU Wien, 1060 Vienna, Austria
Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
Paul Bieber
Institute of Materials Chemistry, TU Wien, 1060 Vienna, Austria
Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
Ulrich Pöschl
Multiphase Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
Konrad Meister
Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, 55128 Mainz, Germany
Department of Chemistry and Biochemistry, Boise State University, Boise, ID 83725, USA
Mischa Bonn
Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, 55128 Mainz, Germany
Janine Fröhlich-Nowoisky
Multiphase Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
Hinrich Grothe
CORRESPONDING AUTHOR
Institute of Materials Chemistry, TU Wien, 1060 Vienna, Austria
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Ting Lei, Hang Su, Nan Ma, Ulrich Pöschl, Alfred Wiedensohler, and Yafang Cheng
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Yunfan Liu, Hang Su, Siwen Wang, Chao Wei, Wei Tao, Mira L. Pöhlker, Christopher Pöhlker, Bruna A. Holanda, Ovid O. Krüger, Thorsten Hoffmann, Manfred Wendisch, Paulo Artaxo, Ulrich Pöschl, Meinrat O. Andreae, and Yafang Cheng
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Guo Li, Hang Su, Meng Li, Uwe Kuhn, Guangjie Zheng, Lei Han, Fengxia Bao, Ulrich Pöschl, and Yafang Cheng
Atmos. Meas. Tech., 15, 6433–6446, https://doi.org/10.5194/amt-15-6433-2022, https://doi.org/10.5194/amt-15-6433-2022, 2022
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Simon F. Reifenberg, Anna Martin, Matthias Kohl, Sara Bacer, Zaneta Hamryszczak, Ivan Tadic, Lenard Röder, Daniel J. Crowley, Horst Fischer, Katharina Kaiser, Johannes Schneider, Raphael Dörich, John N. Crowley, Laura Tomsche, Andreas Marsing, Christiane Voigt, Andreas Zahn, Christopher Pöhlker, Bruna A. Holanda, Ovid Krüger, Ulrich Pöschl, Mira Pöhlker, Patrick Jöckel, Marcel Dorf, Ulrich Schumann, Jonathan Williams, Birger Bohn, Joachim Curtius, Hardwig Harder, Hans Schlager, Jos Lelieveld, and Andrea Pozzer
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Alexander D. Harrison, Daniel O'Sullivan, Michael P. Adams, Grace C. E. Porter, Edmund Blades, Cherise Brathwaite, Rebecca Chewitt-Lucas, Cassandra Gaston, Rachel Hawker, Ovid O. Krüger, Leslie Neve, Mira L. Pöhlker, Christopher Pöhlker, Ulrich Pöschl, Alberto Sanchez-Marroquin, Andrea Sealy, Peter Sealy, Mark D. Tarn, Shanice Whitehall, James B. McQuaid, Kenneth S. Carslaw, Joseph M. Prospero, and Benjamin J. Murray
Atmos. Chem. Phys., 22, 9663–9680, https://doi.org/10.5194/acp-22-9663-2022, https://doi.org/10.5194/acp-22-9663-2022, 2022
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Marco Wietzoreck, Marios Kyprianou, Benjamin A. Musa Bandowe, Siddika Celik, John N. Crowley, Frank Drewnick, Philipp Eger, Nils Friedrich, Minas Iakovides, Petr Kukučka, Jan Kuta, Barbora Nežiková, Petra Pokorná, Petra Přibylová, Roman Prokeš, Roland Rohloff, Ivan Tadic, Sebastian Tauer, Jake Wilson, Hartwig Harder, Jos Lelieveld, Ulrich Pöschl, Euripides G. Stephanou, and Gerhard Lammel
Atmos. Chem. Phys., 22, 8739–8766, https://doi.org/10.5194/acp-22-8739-2022, https://doi.org/10.5194/acp-22-8739-2022, 2022
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A unique dataset of concentrations and sources of polycyclic aromatic hydrocarbons (PAHs) and their alkylated, oxygenated and nitrated derivatives, in total 74 individual species, in the marine atmosphere is presented. Exposure to these substances poses a major health risk. We found very low concentrations over the Arabian Sea, while both local and long-range-transported pollution caused elevated levels over the Mediterranean Sea and the Arabian Gulf.
Ovid O. Krüger, Bruna A. Holanda, Sourangsu Chowdhury, Andrea Pozzer, David Walter, Christopher Pöhlker, Maria Dolores Andrés Hernández, John P. Burrows, Christiane Voigt, Jos Lelieveld, Johannes Quaas, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 22, 8683–8699, https://doi.org/10.5194/acp-22-8683-2022, https://doi.org/10.5194/acp-22-8683-2022, 2022
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The abrupt reduction in human activities during the first COVID-19 lockdown created unprecedented atmospheric conditions. We took the opportunity to quantify changes in black carbon (BC) as a major anthropogenic air pollutant. Therefore, we measured BC on board a research aircraft over Europe during the lockdown and compared the results to measurements from 2017. With model simulations we account for different weather conditions and find a lockdown-related decrease in BC of 41 %.
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.
Marco A. Franco, Florian Ditas, Leslie A. Kremper, Luiz A. T. Machado, Meinrat O. Andreae, Alessandro Araújo, Henrique M. J. Barbosa, Joel F. de Brito, Samara Carbone, Bruna A. Holanda, Fernando G. Morais, Janaína P. Nascimento, Mira L. Pöhlker, Luciana V. Rizzo, Marta Sá, Jorge Saturno, David Walter, Stefan Wolff, Ulrich Pöschl, Paulo Artaxo, and Christopher Pöhlker
Atmos. Chem. Phys., 22, 3469–3492, https://doi.org/10.5194/acp-22-3469-2022, https://doi.org/10.5194/acp-22-3469-2022, 2022
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In Central Amazonia, new particle formation in the planetary boundary layer is rare. Instead, there is the appearance of sub-50 nm aerosols with diameters larger than about 20 nm that eventually grow to cloud condensation nuclei size range. Here, 254 growth events were characterized which have higher predominance in the wet season. About 70 % of them showed direct relation to convective downdrafts, while 30 % occurred partly under clear-sky conditions, evidencing still unknown particle sources.
Kai Tang, Beatriz Sánchez-Parra, Petya Yordanova, Jörn Wehking, Anna T. Backes, Daniel A. Pickersgill, Stefanie Maier, Jean Sciare, Ulrich Pöschl, Bettina Weber, and Janine Fröhlich-Nowoisky
Biogeosciences, 19, 71–91, https://doi.org/10.5194/bg-19-71-2022, https://doi.org/10.5194/bg-19-71-2022, 2022
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Metagenomic sequencing and freezing experiments of aerosol samples collected on Cyprus revealed rain-related short-term changes of bioaerosol and ice nuclei composition. Filtration experiments showed a rain-related enhancement of biological ice nuclei > 5 µm and < 0.1 µm. The observed effects of rainfall on the composition of atmospheric bioaerosols and ice nuclei may influence the hydrological cycle as well as the health effects of air particulate matter (pathogens, allergens).
Luiz A. T. Machado, Marco A. Franco, Leslie A. Kremper, Florian Ditas, Meinrat O. Andreae, Paulo Artaxo, Micael A. Cecchini, Bruna A. Holanda, Mira L. Pöhlker, Ivan Saraiva, Stefan Wolff, Ulrich Pöschl, and Christopher Pöhlker
Atmos. Chem. Phys., 21, 18065–18086, https://doi.org/10.5194/acp-21-18065-2021, https://doi.org/10.5194/acp-21-18065-2021, 2021
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Several studies evaluate aerosol–cloud interactions, but only a few attempted to describe how clouds modify aerosol properties. This study evaluates the effect of weather events on the particle size distribution at the ATTO, combining remote sensing and in situ data. Ultrafine, Aitken and accumulation particles modes have different behaviors for the diurnal cycle and for rainfall events. This study opens up new scientific questions that need to be pursued in detail in new field campaigns.
Ramon Campos Braga, Barbara Ervens, Daniel Rosenfeld, Meinrat O. Andreae, Jan-David Förster, Daniel Fütterer, Lianet Hernández Pardo, Bruna A. Holanda, Tina Jurkat-Witschas, Ovid O. Krüger, Oliver Lauer, Luiz A. T. Machado, Christopher Pöhlker, Daniel Sauer, Christiane Voigt, Adrian Walser, Manfred Wendisch, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 17513–17528, https://doi.org/10.5194/acp-21-17513-2021, https://doi.org/10.5194/acp-21-17513-2021, 2021
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Interactions of aerosol particles with clouds represent a large uncertainty in estimates of climate change. Properties of aerosol particles control their ability to act as cloud condensation nuclei. Using aerosol measurements in the Amazon, we performed model studies to compare predicted and measured cloud droplet number concentrations at cloud bases. Our results confirm previous estimates of particle hygroscopicity in this region.
Najin Kim, Yafang Cheng, Nan Ma, Mira L. Pöhlker, Thomas Klimach, Thomas F. Mentel, Ovid O. Krüger, Ulrich Pöschl, and Hang Su
Atmos. Meas. Tech., 14, 6991–7005, https://doi.org/10.5194/amt-14-6991-2021, https://doi.org/10.5194/amt-14-6991-2021, 2021
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A broad supersaturation scanning CCN (BS2-CCN) system, in which particles are exposed to a range of supersaturation simultaneously, can measure a broad range of CCN activity distribution with a high time resolution. We describe how the BS2-CCN system can be effectively calibrated and which factors can affect the calibration curve. Intercomparison experiments between typical DMA-CCN and BS2-CCN measurements to evaluate the BS2-CCN system showed high correlation and good agreement.
Julia Burkart, Jürgen Gratzl, Teresa M. Seifried, Paul Bieber, and Hinrich Grothe
Biogeosciences, 18, 5751–5765, https://doi.org/10.5194/bg-18-5751-2021, https://doi.org/10.5194/bg-18-5751-2021, 2021
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Extracts of birch pollen grains are known to be ice nucleation active and thus impact cloud formation and climate. In this study we develop an extraction method to separate subpollen particles from ice nucleating macromolecules. Our results thereby illustrate that ice nucleating macromolecules can be washed off the subpollen particles and that the ice activity is linked to the presence of proteins.
Ramon Campos Braga, Daniel Rosenfeld, Ovid O. Krüger, Barbara Ervens, Bruna A. Holanda, Manfred Wendisch, Trismono Krisna, Ulrich Pöschl, Meinrat O. Andreae, Christiane Voigt, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 14079–14088, https://doi.org/10.5194/acp-21-14079-2021, https://doi.org/10.5194/acp-21-14079-2021, 2021
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Quantifying the precipitation within clouds is crucial for our understanding of the Earth's hydrological cycle. Using in situ measurements of cloud and rain properties over the Amazon Basin and Atlantic Ocean, we show here a linear relationship between the effective radius (re) and precipitation water content near the tops of convective clouds for different pollution states and temperature levels. Our results emphasize the role of re to determine both initiation and amount of precipitation.
Maria Prass, Meinrat O. Andreae, Alessandro C. de Araùjo, Paulo Artaxo, Florian Ditas, Wolfgang Elbert, Jan-David Förster, Marco Aurélio Franco, Isabella Hrabe de Angelis, Jürgen Kesselmeier, Thomas Klimach, Leslie Ann Kremper, Eckhard Thines, David Walter, Jens Weber, Bettina Weber, Bernhard M. Fuchs, Ulrich Pöschl, and Christopher Pöhlker
Biogeosciences, 18, 4873–4887, https://doi.org/10.5194/bg-18-4873-2021, https://doi.org/10.5194/bg-18-4873-2021, 2021
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Bioaerosols in the atmosphere over the Amazon rain forest were analyzed by molecular biological staining and microscopy. Eukaryotic, bacterial, and archaeal aerosols were quantified in time series and altitude profiles which exhibited clear differences in number concentrations and vertical distributions. Our results provide insights into the sources and dispersion of different Amazonian bioaerosol types as a basis for a better understanding of biosphere–atmosphere interactions.
Bjorn Stevens, Sandrine Bony, David Farrell, Felix Ament, Alan Blyth, Christopher Fairall, Johannes Karstensen, Patricia K. Quinn, Sabrina Speich, Claudia Acquistapace, Franziska Aemisegger, Anna Lea Albright, Hugo Bellenger, Eberhard Bodenschatz, Kathy-Ann Caesar, Rebecca Chewitt-Lucas, Gijs de Boer, Julien Delanoë, Leif Denby, Florian Ewald, Benjamin Fildier, Marvin Forde, Geet George, Silke Gross, Martin Hagen, Andrea Hausold, Karen J. Heywood, Lutz Hirsch, Marek Jacob, Friedhelm Jansen, Stefan Kinne, Daniel Klocke, Tobias Kölling, Heike Konow, Marie Lothon, Wiebke Mohr, Ann Kristin Naumann, Louise Nuijens, Léa Olivier, Robert Pincus, Mira Pöhlker, Gilles Reverdin, Gregory Roberts, Sabrina Schnitt, Hauke Schulz, A. Pier Siebesma, Claudia Christine Stephan, Peter Sullivan, Ludovic Touzé-Peiffer, Jessica Vial, Raphaela Vogel, Paquita Zuidema, Nicola Alexander, Lyndon Alves, Sophian Arixi, Hamish Asmath, Gholamhossein Bagheri, Katharina Baier, Adriana Bailey, Dariusz Baranowski, Alexandre Baron, Sébastien Barrau, Paul A. Barrett, Frédéric Batier, Andreas Behrendt, Arne Bendinger, Florent Beucher, Sebastien Bigorre, Edmund Blades, Peter Blossey, Olivier Bock, Steven Böing, Pierre Bosser, Denis Bourras, Pascale Bouruet-Aubertot, Keith Bower, Pierre Branellec, Hubert Branger, Michal Brennek, Alan Brewer, Pierre-Etienne Brilouet, Björn Brügmann, Stefan A. Buehler, Elmo Burke, Ralph Burton, Radiance Calmer, Jean-Christophe Canonici, Xavier Carton, Gregory Cato Jr., Jude Andre Charles, Patrick Chazette, Yanxu Chen, Michal T. Chilinski, Thomas Choularton, Patrick Chuang, Shamal Clarke, Hugh Coe, Céline Cornet, Pierre Coutris, Fleur Couvreux, Susanne Crewell, Timothy Cronin, Zhiqiang Cui, Yannis Cuypers, Alton Daley, Gillian M. Damerell, Thibaut Dauhut, Hartwig Deneke, Jean-Philippe Desbios, Steffen Dörner, Sebastian Donner, Vincent Douet, Kyla Drushka, Marina Dütsch, André Ehrlich, Kerry Emanuel, Alexandros Emmanouilidis, Jean-Claude Etienne, Sheryl Etienne-Leblanc, Ghislain Faure, Graham Feingold, Luca Ferrero, Andreas Fix, Cyrille Flamant, Piotr Jacek Flatau, Gregory R. Foltz, Linda Forster, Iulian Furtuna, Alan Gadian, Joseph Galewsky, Martin Gallagher, Peter Gallimore, Cassandra Gaston, Chelle Gentemann, Nicolas Geyskens, Andreas Giez, John Gollop, Isabelle Gouirand, Christophe Gourbeyre, Dörte de Graaf, Geiske E. de Groot, Robert Grosz, Johannes Güttler, Manuel Gutleben, Kashawn Hall, George Harris, Kevin C. Helfer, Dean Henze, Calvert Herbert, Bruna Holanda, Antonio Ibanez-Landeta, Janet Intrieri, Suneil Iyer, Fabrice Julien, Heike Kalesse, Jan Kazil, Alexander Kellman, Abiel T. Kidane, Ulrike Kirchner, Marcus Klingebiel, Mareike Körner, Leslie Ann Kremper, Jan Kretzschmar, Ovid Krüger, Wojciech Kumala, Armin Kurz, Pierre L'Hégaret, Matthieu Labaste, Tom Lachlan-Cope, Arlene Laing, Peter Landschützer, Theresa Lang, Diego Lange, Ingo Lange, Clément Laplace, Gauke Lavik, Rémi Laxenaire, Caroline Le Bihan, Mason Leandro, Nathalie Lefevre, Marius Lena, Donald Lenschow, Qiang Li, Gary Lloyd, Sebastian Los, Niccolò Losi, Oscar Lovell, Christopher Luneau, Przemyslaw Makuch, Szymon Malinowski, Gaston Manta, Eleni Marinou, Nicholas Marsden, Sebastien Masson, Nicolas Maury, Bernhard Mayer, Margarette Mayers-Als, Christophe Mazel, Wayne McGeary, James C. McWilliams, Mario Mech, Melina Mehlmann, Agostino Niyonkuru Meroni, Theresa Mieslinger, Andreas Minikin, Peter Minnett, Gregor Möller, Yanmichel Morfa Avalos, Caroline Muller, Ionela Musat, Anna Napoli, Almuth Neuberger, Christophe Noisel, David Noone, Freja Nordsiek, Jakub L. Nowak, Lothar Oswald, Douglas J. Parker, Carolyn Peck, Renaud Person, Miriam Philippi, Albert Plueddemann, Christopher Pöhlker, Veronika Pörtge, Ulrich Pöschl, Lawrence Pologne, Michał Posyniak, Marc Prange, Estefanía Quiñones Meléndez, Jule Radtke, Karim Ramage, Jens Reimann, Lionel Renault, Klaus Reus, Ashford Reyes, Joachim Ribbe, Maximilian Ringel, Markus Ritschel, Cesar B. Rocha, Nicolas Rochetin, Johannes Röttenbacher, Callum Rollo, Haley Royer, Pauline Sadoulet, Leo Saffin, Sanola Sandiford, Irina Sandu, Michael Schäfer, Vera Schemann, Imke Schirmacher, Oliver Schlenczek, Jerome Schmidt, Marcel Schröder, Alfons Schwarzenboeck, Andrea Sealy, Christoph J. Senff, Ilya Serikov, Samkeyat Shohan, Elizabeth Siddle, Alexander Smirnov, Florian Späth, Branden Spooner, M. Katharina Stolla, Wojciech Szkółka, Simon P. de Szoeke, Stéphane Tarot, Eleni Tetoni, Elizabeth Thompson, Jim Thomson, Lorenzo Tomassini, Julien Totems, Alma Anna Ubele, Leonie Villiger, Jan von Arx, Thomas Wagner, Andi Walther, Ben Webber, Manfred Wendisch, Shanice Whitehall, Anton Wiltshire, Allison A. Wing, Martin Wirth, Jonathan Wiskandt, Kevin Wolf, Ludwig Worbes, Ethan Wright, Volker Wulfmeyer, Shanea Young, Chidong Zhang, Dongxiao Zhang, Florian Ziemen, Tobias Zinner, and Martin Zöger
Earth Syst. Sci. Data, 13, 4067–4119, https://doi.org/10.5194/essd-13-4067-2021, https://doi.org/10.5194/essd-13-4067-2021, 2021
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The EUREC4A field campaign, designed to test hypothesized mechanisms by which clouds respond to warming and benchmark next-generation Earth-system models, is presented. EUREC4A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. It was the first campaign that attempted to characterize the full range of processes and scales influencing trade wind clouds.
Mira L. Pöhlker, Minghui Zhang, Ramon Campos Braga, Ovid O. Krüger, Ulrich Pöschl, and Barbara Ervens
Atmos. Chem. Phys., 21, 11723–11740, https://doi.org/10.5194/acp-21-11723-2021, https://doi.org/10.5194/acp-21-11723-2021, 2021
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Clouds cool our atmosphere. The role of small aerosol particles in affecting them represents one of the largest uncertainties in current estimates of climate change. Traditionally it is assumed that cloud droplets only form particles of diameters ~ 100 nm (
accumulation mode). Previous studies suggest that this can also occur in smaller particles (
Aitken mode). Our study provides a general framework to estimate under which aerosol and cloud conditions Aitken mode particles affect clouds.
Haijie Tong, Fobang Liu, Alexander Filippi, Jake Wilson, Andrea M. Arangio, Yun Zhang, Siyao Yue, Steven Lelieveld, Fangxia Shen, Helmi-Marja K. Keskinen, Jing Li, Haoxuan Chen, Ting Zhang, Thorsten Hoffmann, Pingqing Fu, William H. Brune, Tuukka Petäjä, Markku Kulmala, Maosheng Yao, Thomas Berkemeier, Manabu Shiraiwa, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 10439–10455, https://doi.org/10.5194/acp-21-10439-2021, https://doi.org/10.5194/acp-21-10439-2021, 2021
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We measured radical yields of aqueous PM2.5 extracts and found lower yields at higher concentrations of PM2.5. Abundances of water-soluble transition metals and aromatics in PM2.5 were positively correlated with the relative fraction of •OH but negatively correlated with the relative fraction of C-centered radicals among detected radicals. Composition-dependent reactive species yields may explain differences in the reactivity and health effects of PM2.5 in clean versus polluted air.
Theresa Haller, Eva Sommer, Thomas Steinkogler, Christian Rentenberger, Anna Wonaschuetz, Anne Kasper-Giebl, Hinrich Grothe, and Regina Hitzenberger
Atmos. Meas. Tech., 14, 3721–3735, https://doi.org/10.5194/amt-14-3721-2021, https://doi.org/10.5194/amt-14-3721-2021, 2021
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Structural changes of carbonaceous aerosol samples during thermal–optical measurement techniques cause a darkening of the sample during the heating procedure which can influence the attribution of the carbonaceous material to organic and elemental carbon. We analyzed structural changes of atmospheric aerosol samples occurring during the EUSAAR2 and NIOSH870 measurement protocols with Raman spectroscopy. We found that the darkening of the sample is not necessarily caused by graphitization.
Eugene F. Mikhailov, Mira L. Pöhlker, Kathrin Reinmuth-Selzle, Sergey S. Vlasenko, Ovid O. Krüger, Janine Fröhlich-Nowoisky, Christopher Pöhlker, Olga A. Ivanova, Alexey A. Kiselev, Leslie A. Kremper, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 6999–7022, https://doi.org/10.5194/acp-21-6999-2021, https://doi.org/10.5194/acp-21-6999-2021, 2021
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Subpollen particles are a relatively new subset of atmospheric aerosol particles. When pollen grains rupture, they release cytoplasmic fragments known as subpollen particles (SPPs). We found that SPPs, containing a broad spectrum of biopolymers and hydrocarbons, exhibit abnormally high water uptake. This effect may influence the life cycle of SPPs and the related direct and indirect impacts on radiation budget as well as reinforce their allergic potential.
Patricia K. Quinn, Elizabeth J. Thompson, Derek J. Coffman, Sunil Baidar, Ludovic Bariteau, Timothy S. Bates, Sebastien Bigorre, Alan Brewer, Gijs de Boer, Simon P. de Szoeke, Kyla Drushka, Gregory R. Foltz, Janet Intrieri, Suneil Iyer, Chris W. Fairall, Cassandra J. Gaston, Friedhelm Jansen, James E. Johnson, Ovid O. Krüger, Richard D. Marchbanks, Kenneth P. Moran, David Noone, Sergio Pezoa, Robert Pincus, Albert J. Plueddemann, Mira L. Pöhlker, Ulrich Pöschl, Estefania Quinones Melendez, Haley M. Royer, Malgorzata Szczodrak, Jim Thomson, Lucia M. Upchurch, Chidong Zhang, Dongxiao Zhang, and Paquita Zuidema
Earth Syst. Sci. Data, 13, 1759–1790, https://doi.org/10.5194/essd-13-1759-2021, https://doi.org/10.5194/essd-13-1759-2021, 2021
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ATOMIC took place in the northwestern tropical Atlantic during January and February of 2020 to gather information on shallow atmospheric convection, the effects of aerosols and clouds on the ocean surface energy budget, and mesoscale oceanic processes. Measurements made from the NOAA RV Ronald H. Brown and assets it deployed (instrumented mooring and uncrewed seagoing vehicles) are described herein to advance widespread use of the data by the ATOMIC and broader research communities.
Jake Wilson, Ulrich Pöschl, Manabu Shiraiwa, and Thomas Berkemeier
Atmos. Chem. Phys., 21, 6175–6198, https://doi.org/10.5194/acp-21-6175-2021, https://doi.org/10.5194/acp-21-6175-2021, 2021
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This work explores the gas–particle partitioning of PAHs on soot with a kinetic model. We show that the equilibration timescale depends on PAH molecular structure, temperature, and particle number concentration. We explore scenarios in which the particulate fraction is perturbed from equilibrium by chemical loss and discuss implications for chemical transport models that assume instantaneous equilibration at each model time step.
Manabu Shiraiwa and Ulrich Pöschl
Atmos. Chem. Phys., 21, 1565–1580, https://doi.org/10.5194/acp-21-1565-2021, https://doi.org/10.5194/acp-21-1565-2021, 2021
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Mass accommodation is a crucial process in secondary organic aerosol partitioning that depends on volatility, diffusivity, reactivity, and particle penetration depth of the chemical species involved. For efficient kinetic modeling, we introduce an effective mass accommodation coefficient that accounts for the above influencing factors, can be applied in the common Fuchs–Sutugin approximation, and helps to resolve inconsistencies and shortcomings of earlier experimental and model investigations.
Chuchu Chen, Xiaoxiang Wang, Kurt Binder, Mohammad Mehdi Ghahremanpour, David van der Spoel, Ulrich Pöschl, Hang Su, and Yafang Cheng
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1329, https://doi.org/10.5194/acp-2020-1329, 2021
Publication in ACP not foreseen
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Size dependence of succinic acid solvation in the nanoparticles is investigated based on the molecular dynamics (MD) simulation and energetic analysis. The results show a stronger surface preference and a weaker internal bulk volume solvation of succinic acid in the smaller droplets, which may explain the previously observed size-dependent phase-state of aerosol nanoparticles containing organic molecules, fundamentally promoting a better understanding of atmospheric aerosols.
Teresa M. Seifried, Paul Bieber, Laura Felgitsch, Julian Vlasich, Florian Reyzek, David G. Schmale III, and Hinrich Grothe
Biogeosciences, 17, 5655–5667, https://doi.org/10.5194/bg-17-5655-2020, https://doi.org/10.5194/bg-17-5655-2020, 2020
Guo Li, Hang Su, Nan Ma, Guangjie Zheng, Uwe Kuhn, Meng Li, Thomas Klimach, Ulrich Pöschl, and Yafang Cheng
Atmos. Meas. Tech., 13, 6053–6065, https://doi.org/10.5194/amt-13-6053-2020, https://doi.org/10.5194/amt-13-6053-2020, 2020
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Aerosol acidity plays an important role in regulating the chemistry, health, and ecological effect of aerosol particles. However, a direct measurement of aerosol pH is very challenging because of its fast transition and equilibrium with adjacent environments. Therefore, most early studies have to use modeled pH, resulting in intensive debates about model uncertainties. Here we developed an optimized approach to measure aerosol pH by using pH-indicator papers combined with RGB-based colorimetry.
Lixia Liu, Yafang Cheng, Siwen Wang, Chao Wei, Mira L. Pöhlker, Christopher Pöhlker, Paulo Artaxo, Manish Shrivastava, Meinrat O. Andreae, Ulrich Pöschl, and Hang Su
Atmos. Chem. Phys., 20, 13283–13301, https://doi.org/10.5194/acp-20-13283-2020, https://doi.org/10.5194/acp-20-13283-2020, 2020
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This modeling paper reveals how aerosol–cloud interactions (ACIs) and aerosol–radiation interactions (ARIs) induced by biomass burning (BB) aerosols act oppositely on radiation, cloud, and precipitation in the Amazon during the dry season. The varying relative significance of ACIs and ARIs with BB aerosol concentration leads to a nonlinear dependence of the total climate response on BB aerosol loading and features the growing importance of ARIs at high aerosol loading.
Ting Lei, Nan Ma, Juan Hong, Thomas Tuch, Xin Wang, Zhibin Wang, Mira Pöhlker, Maofa Ge, Weigang Wang, Eugene Mikhailov, Thorsten Hoffmann, Ulrich Pöschl, Hang Su, Alfred Wiedensohler, and Yafang Cheng
Atmos. Meas. Tech., 13, 5551–5567, https://doi.org/10.5194/amt-13-5551-2020, https://doi.org/10.5194/amt-13-5551-2020, 2020
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We present the design of a nano-hygroscopicity tandem differential mobility analyzer (nano-HTDMA) apparatus that enables high accuracy and precision in hygroscopic growth measurements of aerosol nanoparticles with diameters less than 10 nm. We further introduce comprehensive methods for system calibration and validation of the performance of the system. We then study the size dependence of the deliquescence and the efflorescence of aerosol nanoparticles for sizes down to 6 nm.
Wei Tao, Hang Su, Guangjie Zheng, Jiandong Wang, Chao Wei, Lixia Liu, Nan Ma, Meng Li, Qiang Zhang, Ulrich Pöschl, and Yafang Cheng
Atmos. Chem. Phys., 20, 11729–11746, https://doi.org/10.5194/acp-20-11729-2020, https://doi.org/10.5194/acp-20-11729-2020, 2020
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We simulated the thermodynamic and multiphase reactions in aerosol water during a wintertime haze event over the North China Plain. It was found that aerosol pH exhibited a strong spatiotemporal variability, and multiple oxidation pathways were predominant for particulate sulfate formation in different locations. Sensitivity tests further showed that ammonia, crustal particles, and dissolved transition metal ions were important factors for multiphase chemistry during haze episodes.
Cited articles
Adar, C., Sirotinskaya, V., Bar Dolev, M., Friehmann, T., and Braslavsky, I.: Falling water ice affinity purification of ice-binding proteins, Sci. Rep., 8, 11046, https://doi.org/10.1038/s41598-018-29312-x, 2018.
Alsante, A. N., Thornton, D. C. O., and Brooks, S. D.: Effect of Aggregation and Molecular Size on the Ice Nucleation Efficiency of Proteins, Environ. Sci. Technol., 58, 4594–4605, https://doi.org/10.1021/acs.est.3c06835, 2024.
Augustin, S., Wex, H., Niedermeier, D., Pummer, B., Grothe, H., Hartmann, S., Tomsche, L., Clauss, T., Voigtländer, J., Ignatius, K., and Stratmann, F.: Immersion freezing of birch pollen washing water, Atmos. Chem. Phys., 13, 10989–11003, https://doi.org/10.5194/acp-13-10989-2013, 2013.
Bar Dolev, M., Braslavsky, I., and Davies, P. L.: Ice-binding proteins and their function, Annu. Rev. Biochem., 85, 515–542, https://doi.org/10.1146/annurev-biochem-060815-014546, 2016.
Bieber, P. and Borduas-Dedekind, N.: High-speed cryo-microscopy reveals that ice-nucleating proteins of Pseudomonas syringae trigger freezing at hydrophobic interfaces, Sci. Adv., 10, eadn6606, https://doi.org/10.1126/sciadv.adn6606, 2024.
Bieber, P., Seifried, T. M., Burkart, J., Gratzl, J., Kasper-Giebl, A., Schmale, D. G., and Grothe, H.: A drone-based bioaerosol sampling system to monitor ice nucleation particles in the lower atmosphere, Remote Sens., 12, 552, https://doi.org/10.3390/rs12030552, 2020.
Burkart, J., Gratzl, J., Seifried, T. M., Bieber, P., and Grothe, H.: Isolation of subpollen particles (SPPs) of birch: SPPs are potential carriers of ice nucleating macromolecules, Biogeosciences, 18, 5751–5765, https://doi.org/10.5194/bg-18-5751-2021, 2021.
Burke, M. J. and Lindow, S. E.: Surface properties and size of the ice nucleation site in ice nucleation active bacteria: theoretical considerations, Cryobiology, 27, 80–84, https://doi.org/10.1016/0011-2240(90)90054-8, 1990.
Corotto, L. V., Wolber, P. K., and Warren, G. J.: Ice nucleation activity of Pseudomonas fluorescens: mutagenesis, complementation analysis and identification of a gene product, EMBO J., 5, 231–236, https://doi.org/10.1002/j.1460-2075.1986.tb04203.x, 1986.
Daily, M. I., Tarn, M. D., Whale, T. F., and Murray, B. J.: An evaluation of the heat test for the ice-nucleating ability of minerals and biological material, Atmos. Meas. Tech., 15, 2635–2665, https://doi.org/10.5194/amt-15-2635-2022, 2022.
de Almeida Ribeiro, I., Meister, K., and Molinero, V.: HUB: a method to model and extract the distribution of ice nucleation temperatures from drop-freezing experiments, Atmos. Chem. Phys., 23, 5623–5639, https://doi.org/10.5194/acp-23-5623-2023, 2023.
DeMott, P. J., Möhler, O., Cziczo, D. J., Hiranuma, N., Petters, M. D., Petters, S. S., Belosi, F., Bingemer, H. G., Brooks, S. D., Budke, C., Burkert-Kohn, M., Collier, K. N., Danielczok, A., Eppers, O., Felgitsch, L., Garimella, S., Grothe, H., Herenz, P., Hill, T. C. J., Höhler, K., Kanji, Z. A., Kiselev, A., Koop, T., Kristensen, T. B., Krüger, K., Kulkarni, G., Levin, E. J. T., Murray, B. J., Nicosia, A., O'Sullivan, D., Peckhaus, A., Polen, M. J., Price, H. C., Reicher, N., Rothenberg, D. A., Rudich, Y., Santachiara, G., Schiebel, T., Schrod, J., Seifried, T. M., Stratmann, F., Sullivan, R. C., Suski, K. J., Szakáll, M., Taylor, H. P., Ullrich, R., Vergara-Temprado, J., Wagner, R., Whale, T. F., Weber, D., Welti, A., Wilson, T. W., Wolf, M. J., and Zenker, J.: The Fifth International Workshop on Ice Nucleation phase 2 (FIN-02): laboratory intercomparison of ice nucleation measurements, Atmos. Meas. Tech., 11, 6231–6257, https://doi.org/10.5194/amt-11-6231-2018, 2018.
DeVries, A. L. and Wohlschlag, D. E.: Freezing Resistance in Some Antarctic Fishes, Science, 163, 1073–1075, https://doi.org/10.1126/science.163.3871.1073, 1969.
Diehl, K., Quick, C., Matthias-Maser, S., Mitra, S. K., and Jaenicke, R.: The ice nucleating ability of pollen part I: laboratory studies in deposition and condensation freezing modes, Atmos. Res., 58, 75–87, https://doi.org/10.1016/s0169-8095(01)00091-6, 2001.
Dreischmeier, K.: Heterogene eisnukleations- und antigefriereigenschaften von biomolekülen, Universität Bielefeld, PhD Thesis, https://doi.org/10.4119/unibi/2934018, 2019.
Dreischmeier, K., Budke, C., Wiehemeier, L., Kottke, T., and Koop, T.: Boreal pollen contain ice-nucleating as well as ice-binding “antifreeze” polysaccharides, Sci. Rep., 7, 41890, https://doi.org/10.1038/srep41890, 2017.
Eufemio, R. J., de Almeida Ribeiro, I., Sformo, T. L., Laursen, G. A., Molinero, V., Fröhlich-Nowoisky, J., Bonn, M., and Meister, K.: Lichen species across Alaska produce highly active and stable ice nucleators, Biogeosciences, 20, 2805–2812, https://doi.org/10.5194/bg-20-2805-2023, 2023.
Felgitsch, L.: Ice nucleation activity of boreal plants with focus on birch trees, Wien, PhD Thesis, https://doi.org/10.34726/hss.2019.23059, 2019.
Felgitsch, L., Baloh, P., Burkart, J., Mayr, M., Momken, M. E., Seifried, T. M., Winkler, P., Schmale III, D. G., and Grothe, H.: Birch leaves and branches as a source of ice-nucleating macromolecules, Atmos. Chem. Phys., 18, 16063–16079, https://doi.org/10.5194/acp-18-16063-2018, 2018.
Forbes, J., Bissoyi, A., Eickhoff, L., Reicher, N., Hansen, T., Bon, C. G., Walker, V. K., Koop, T., Rudich, Y., Braslavsky, I., and Davies, P. L.: Water-organizing motif continuity is critical for potent ice nucleation protein activity, Nat. Commun., 13, 5019, https://doi.org/10.1038/s41467-022-32469-9, 2022.
Fröhlich-Nowoisky, J., Hill, T. C. J., Pummer, B. G., Yordanova, P., Franc, G. D., and Pöschl, U.: Ice nucleation activity in the widespread soil fungus Mortierella alpina, Biogeosciences, 12, 1057–1071, https://doi.org/10.5194/bg-12-1057-2015, 2015.
Gajhede, M., Osmark, P., Poulsen, F. M., Ipsen, H., Larsen, J. N., van Neerven, R. J. J., Schou, C., Løwenstein, H., and Spangfort, M. D.: X-ray and NMR structure of Bet v 1, the origin of birch pollen allergy, Nat. Struct. Mol. Biol., 3, 1040–1045, https://doi.org/10.1038/nsb1296-1040, 1996.
Garnham, C. P., Campbell, R. L., Walker, V. K., and Davies, P. L.: Novel dimeric β-helical model of an ice nucleation protein with bridged active sites, BMC Struct. Biol., 11, 36, https://doi.org/10.1186/1472-6807-11-36, 2011.
Govindarajan, A. G. and Lindow, S. E.: Size of bacterial ice-nucleation sites measured in situ by radiation inactivation analysis, P. Natl. Acad. Sci. USA, 85, 1334–1338, https://doi.org/10.1073/pnas.85.5.1334, 1988.
Graether, S. P. and Jia, Z.: Modeling Pseudomonas syringae ice-nucleation protein as a β-helical protein, Biophys. J., 80, 1169–1173, https://doi.org/10.1016/s0006-3495(01)76093-6, 2001.
Green, R. L. and Warren, G. J.: Physical and functional repetition in a bacterial ice nucleation gene, Nature, 317, 645–648, https://doi.org/10.1038/317645a0, 1985.
Gurian-Sherman, D. and Lindow, S. E.: Differential effects of growth temperature on ice nuclei active at different temperatures that are produced by cells of Pseudomonas syringae, Cryobiology, 32, 129–138, https://doi.org/10.1006/cryo.1995.1012, 1995.
Hakim, A., Nguyen, J. B., Basu, K., Zhu, D. F., Thakral, D., Davies, P. L., Isaacs, F. J., Modis, Y., and Meng, W.: Crystal structure of an insect antifreeze protein and its implications for ice binding, J. Biol. Chem., 288, 12295–12304, https://doi.org/10.1074/jbc.m113.450973, 2013.
Kajava, A. V. and Lindow, S. E.: A model of the three-dimensional structure of ice nucleation proteins, J. Mol. Biol., 232, 709–717, https://doi.org/10.1006/jmbi.1993.1424, 1993.
Knopf, D. A. and Alpert, P. A.: Atmospheric ice nucleation, Nat. Rev. Phys., 5, 203–217, https://doi.org/10.1038/s42254-023-00570-7, 2023.
Kofler, S., Asam, C., Eckhard, U., Wallner, M., Ferreira, F., and Brandstetter, H.: Crystallographically Mapped Ligand Binding Differs in High and Low IgE Binding Isoforms of Birch Pollen Allergen Bet v 1, J. Mol. Biol., 422, 109–123, https://doi.org/10.1016/j.jmb.2012.05.016, 2012.
Kozloff, L. M., Turner, M. A., and Arellano, F.: Formation of bacterial membrane ice-nucleating lipoglycoprotein complexes, J. Bacteriol., 173, 6528–6536, https://doi.org/10.1128/jb.173.20.6528-6536.1991, 1991.
Kunert, A. T., Lamneck, M., Helleis, F., Pöschl, U., Pöhlker, M. L., and Fröhlich-Nowoisky, J.: Twin-plate Ice Nucleation Assay (TINA) with infrared detection for high-throughput droplet freezing experiments with biological ice nuclei in laboratory and field samples, Atmos. Meas. Tech., 11, 6327–6337, https://doi.org/10.5194/amt-11-6327-2018, 2018.
Lau, K. M. and Wu, H. T.: Warm rain processes over tropical oceans and climate implications, Geophys. Res. Lett., 30, 2290, https://doi.org/10.1029/2003gl018567, 2003.
Leinala, E. K., Davies, P. L., Doucet, D., Tyshenko, M. G., Walker, V. K., and Jia, Z.: A β-helical antifreeze protein isoform with increased activity: structural and functional insights, J. Biol. Chem., 277, 33349–33352, https://doi.org/10.1074/jbc.m205575200, 2002.
Ling, M. L., Wex, H., Grawe, S., Jakobsson, J., Löndahl, J., Hartmann, S., Finster, K., Boesen, T., and Šantl-Temkiv, T.: Effects of ice nucleation protein repeat number and oligomerization level on ice nucleation activity, J. Geophys. Res.-Atmos., 123, 1802–1810, https://doi.org/10.1002/2017jd027307, 2018.
Liou, Y.-C., Tocilj, A., Davies, P. L., and Jia, Z.: Mimicry of ice structure by surface hydroxyls and water of a β-helix antifreeze protein, Nature, 406, 322–324, https://doi.org/10.1038/35018604, 2000.
Lukas, M., Schwidetzky, R., Kunert, A. T., Backus, E. H. G., Pöschl, U., Fröhlich-Nowoisky, J., Bonn, M., and Meister, K.: Interfacial water ordering is insufficient to explain ice-nucleating protein activity, J. Phys. Chem. Lett., 12, 218–223, https://doi.org/10.1021/acs.jpclett.0c03163, 2021.
Lukas, M., Schwidetzky, R., Eufemio, R. J., Bonn, M., and Meister, K.: Toward understanding bacterial ice nucleation, J. Phys. Chem. B, 126, 1861–1867, https://doi.org/10.1021/acs.jpcb.1c09342, 2022.
Marshall, C. J., Basu, K., and Davies, P. L.: Ice-shell purification of ice-binding proteins, Cryobiology, 72, 258–263, https://doi.org/10.1016/j.cryobiol.2016.03.009, 2016.
Miller, A. J., Brennan, K. P., Mignani, C., Wieder, J., David, R. O., and Borduas-Dedekind, N.: Development of the drop Freezing Ice Nuclei Counter (FINC), intercomparison of droplet freezing techniques, and use of soluble lignin as an atmospheric ice nucleation standard, Atmos. Meas. Tech., 14, 3131–3151, https://doi.org/10.5194/amt-14-3131-2021, 2021.
Murray, K. A., Kinney, N. L. H., Griffiths, C. A., Hasan, M., Gibson, M. I., and Whale, T. F.: Pollen derived macromolecules serve as a new class of ice-nucleating cryoprotectants, Sci. Rep., 12, 12295, https://doi.org/10.1038/s41598-022-15545-4, 2022.
Nandy, L., Fenton, J. L., and Freedman, M. A.: Heterogeneous Ice Nucleation in Model Crystalline Porous Organic Polymers: Influence of Pore Size on Immersion Freezing, J. Phys. Chem. A, 127, 6300–6308, https://doi.org/10.1021/acs.jpca.3c00071, 2023.
Neudecker, P., Nerkamp, J., Eisenmann, A., Nourse, A., Lauber, T., Schweimer, K., Lehmann, K., Schwarzinger, S., Ferreira, F., and Rösch, P.: Solution Structure, Dynamics, and Hydrodynamics of the Calcium-bound Cross-reactive Birch Pollen Allergen Bet v 4 Reveal a Canonical Monomeric Two EF-Hand Assembly with a Regulatory Function, J. Mol. Biol., 336, 1141–1157, https://doi.org/10.1016/j.jmb.2003.12.070, 2004.
O'Sullivan, D., Murray, B. J., Ross, J. F., Whale, T. F., Price, H. C., Atkinson, J. D., Umo, N. S., and Webb, M. E.: The relevance of nanoscale biological fragments for ice nucleation in clouds, Sci. Rep., 5, 8082, https://doi.org/10.1038/srep08082, 2015.
O'Sullivan, D., Murray, B. J., Ross, J. F., Whale, T. F., Price, H. C., Atkinson, J. D., Umo, N. S., and Webb, M. E.: The relevance of nanoscale biological fragments for ice nucleation in clouds, Sci. Rep., 5, 8082, https://doi.org/10.1038/srep08082, 2015.
Polen, M., Lawlis, E., and Sullivan, R. C.: The unstable ice nucleation properties of Snomax® bacterial particles, J. Geophys. Res.-Atmos., 121, 11666–11678, https://doi.org/10.1002/2016jd025251, 2016.
Pouleur, S., Richard, C., Martin, J., and Antoun, H.: Ice nucleation activity in Fusarium acuminatum and Fusarium avenaceum, Appl. Environ. Microbiol. 58, 2960–2964, https://doi.org/10.1128/aem.58.9.2960-2964.1992, 1992.
Pummer, B. G., Bauer, H., Bernardi, J., Bleicher, S., and Grothe, H.: Suspendable macromolecules are responsible for ice nucleation activity of birch and conifer pollen, Atmos. Chem. Phys., 12, 2541–2550, https://doi.org/10.5194/acp-12-2541-2012, 2012.
Pummer, B. G., Bauer, H., Bernardi, J., Chazallon, B., Facq, S., Lendl, B., Whitmore, K., and Grothe, H.: Chemistry and morphology of dried-up pollen suspension residues: Chemistry and morphology of pollen suspension residues, J. Raman Spectrosc., 44, 1654–1658, https://doi.org/10.1002/jrs.4395, 2013.
Pummer, B. G., Budke, C., Augustin-Bauditz, S., Niedermeier, D., Felgitsch, L., Kampf, C. J., Huber, R. G., Liedl, K. R., Loerting, T., Moschen, T., Schauperl, M., Tollinger, M., Morris, C. E., Wex, H., Grothe, H., Pöschl, U., Koop, T., and Fröhlich-Nowoisky, J.: Ice nucleation by water-soluble macromolecules, Atmos. Chem. Phys., 15, 4077–4091, https://doi.org/10.5194/acp-15-4077-2015, 2015.
Qiu, Y., Hudait, A., and Molinero, V.: How size and aggregation of ice-binding proteins control their ice nucleation efficiency, J. Am. Chem. Soc., 141, 7439–7452, https://doi.org/10.1021/jacs.9b01854, 2019.
Rangel-Alvarado, R. B., Nazarenko, Y., and Ariya, P. A.: Snow-borne nanosized particles: abundance, distribution, composition, and significance in ice nucleation processes, J. Geophys. Res.-Atmos., 120, 11760–11774, https://doi.org/10.1002/2015jd023773, 2015.
Raymond, J. A. and DeVries, A. L.: Adsorption inhibition as a mechanism of freezing resistance in polar fishes, P. Natl. Acad. Sci. USA, 74, 2589–2593, https://doi.org/10.1073/pnas.74.6.2589, 1977.
Schwidetzky, R., Kunert, A. T., Bonn, M., Pöschl, U., Ramløv, H., DeVries, A. L., Fröhlich-Nowoisky, J., and Meister, K.: Inhibition of bacterial ice nucleators is not an intrinsic property of antifreeze proteins, J. Phys. Chem. B, 124, 4889–4895, https://doi.org/10.1021/acs.jpcb.0c03001, 2020.
Schwidetzky, R., Sun, Y., Fröhlich-Nowoisky, J., Kunert, A. T., Bonn, M., and Meister, K.: Ice nucleation activity of perfluorinated organic acids, J. Phys. Chem. Lett., 12, 3431–3435, https://doi.org/10.1021/acs.jpclett.1c00604, 2021.
Schwidetzky, R., de Almeida Ribeiro, I., Bothen, N., Backes, A. T., DeVries, A. L., Bonn, M., Fröhlich-Nowoisky, J., Molinero, V., and Meister, K.: Functional aggregation of cell-free proteins enables fungal ice nucleation, P. Natl. Acad. Sci. USA, 120, e2303243120, https://doi.org/10.1073/pnas.2303243120, 2023.
Seifried, T. M., Bieber, P., Felgitsch, L., Vlasich, J., Reyzek, F., Schmale III, D. G., and Grothe, H.: Surfaces of silver birch (Betula pendula) are sources of biological ice nuclei: in vivo and in situ investigations, Biogeosciences, 17, 5655–5667, https://doi.org/10.5194/bg-17-5655-2020, 2020.
Seifried, T. M., Bieber, P., Kunert, A. T., Schmale, D. G., Whitmore, K., Fröhlich-Nowoisky, J., and Grothe, H.: Ice nucleation activity of alpine bioaerosol emitted in vicinity of a birch forest, Atmosphere, 12, 779, https://doi.org/10.3390/atmos12060779, 2021.
Seifried, T. M., Reyzek, F., Bieber, P., and Grothe, H.: Scots pines (Pinus sylvestris) as sources of biological ice-nucleating macromolecules (INMs), Atmosphere, 14, 266, https://doi.org/10.3390/atmos14020266, 2023.
Soh, W. T., Briza, P., Dall, E., Asam, C., Schubert, M., Huber, S., Aglas, L., Bohle, B., Ferreira, F., and Brandstetter, H.: Two Distinct Conformations in Bet v 2 Determine Its Proteolytic Resistance to Cathepsin S, Int. J. Mol. Sci., 18, 2156, https://doi.org/10.3390/ijms18102156, 2017.
Tong, H.-J., Ouyang, B., Nikolovski, N., Lienhard, D. M., Pope, F. D., and Kalberer, M.: A new electrodynamic balance (EDB) design for low-temperature studies: application to immersion freezing of pollen extract bioaerosols, Atmos. Meas. Tech., 8, 1183–1195, https://doi.org/10.5194/amt-8-1183-2015, 2015.
Vali, G.: Quantitative evaluation of experimental results on the heterogeneous freezing nucleation of supercooled liquids, J. Atmos. Sci., 28, 402–409, https://doi.org/10.1175/1520-0469(1971)028<0402:qeoera>2.0.co;2, 1971.
Vali, G.: Interpretation of freezing nucleation experiments: singular and stochastic; sites and surfaces, Atmos. Chem. Phys., 14, 5271–5294, https://doi.org/10.5194/acp-14-5271-2014, 2014.
Wright, T. P., Petters, M. D., Hader, J. D., Morton, T., and Holder, A. L.: Minimal cooling rate dependence of ice nuclei activity in the immersion mode, J. Geophys. Res.-Atmos., 118, 10535–10543, https://doi.org/10.1002/jgrd.50810, 2013.
Zhang, Y., Zhang, H., Ding, X., Cheng, L., Wang, L., Qian, H., Qi, X., and Song, C.: Purification and identification of antifreeze protein from cold-acclimated oat (Avena sativa L.) and the cryoprotective activities in ice cream, Food Bioprocess Tech., 9, 1746–1755, https://doi.org/10.1007/s11947-016-1750-x, 2016.
Short summary
Betula pendula is a widespread birch tree species containing ice nucleation agents that can trigger the freezing of cloud droplets and thereby alter the evolution of clouds. Our study identifies three distinct ice-nucleating macromolecule (INM) aggregates of varying size that can nucleate ice at temperatures up to –5.4°C. Our findings suggest that these vegetation-derived particles may influence atmospheric processes, weather, and climate more strongly than previously thought.
Betula pendula is a widespread birch tree species containing ice nucleation agents that can...
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