Articles | Volume 5, issue 12
Research article 20 Dec 2012
Research article | 20 Dec 2012
Single Particle Soot Photometer intercomparison at the AIDA chamber
M. Laborde et al.
P. Zieger, P. P. Aalto, V. Aaltonen, M. Äijälä, J. Backman, J. Hong, M. Komppula, R. Krejci, M. Laborde, J. Lampilahti, G. de Leeuw, A. Pfüller, B. Rosati, M. Tesche, P. Tunved, R. Väänänen, and T. Petäjä
Atmos. Chem. Phys., 15, 7247–7267,Short summary
The effect of water uptake (hygroscopicity) on aerosol light scattering properties is generally lower for boreal aerosol due to the dominance of organic substances. A columnar optical closure study using ground-based and airborne measurements of aerosol optical, chemical and microphysical properties was conducted and the implications and limitations are discussed.
J. C. Corbin, B. Sierau, M. Gysel, M. Laborde, A. Keller, J. Kim, A. Petzold, T. B. Onasch, U. Lohmann, and A. A. Mensah
Atmos. Chem. Phys., 14, 2591–2603,
Z. Jurányi, T. Tritscher, M. Gysel, M. Laborde, L. Gomes, G. Roberts, U. Baltensperger, and E. Weingartner
Atmos. Chem. Phys., 13, 6431–6446,
M. Laborde, M. Crippa, T. Tritscher, Z. Jurányi, P. F. Decarlo, B. Temime-Roussel, N. Marchand, S. Eckhardt, A. Stohl, U. Baltensperger, A. S. H. Prévôt, E. Weingartner, and M. Gysel
Atmos. Chem. Phys., 13, 5831–5856,
M. Gysel, M. Laborde, A. A. Mensah, J. C. Corbin, A. Keller, J. Kim, A. Petzold, and B. Sierau
Atmos. Meas. Tech., 5, 3099–3107,
Zixia Liu, Martin Osborne, Karen Anderson, Jamie D. Shutler, Andy Wilson, Justin Langridge, Steve H. L. Yim, Hugh Coe, Suresh Babu, Sreedharan K. Satheesh, Paquita Zuidema, Tao Huang, Jack C. H. Cheng, and James Haywood
Atmos. Meas. Tech., 14, 6101–6118,Short summary
This paper first validates the performance of an advanced aerosol observation instrument POPS against a reference instrument and examines any biases introduced by operating it on a quadcopter drone. The results show the POPS performs relatively well on the ground. The impact of the UAV rotors on the POPS is small at low wind speeds, but when operating under higher wind speeds, larger discrepancies occur. It appears that the POPS measures sub-micron aerosol particles more accurately on the UAV.
Christian Tatzelt, Silvia Henning, André Welti, Andrea Baccarini, Markus Hartmann, Martin Gysel-Beer, Manuela van Pinxteren, Robin L. Modini, Julia Schmale, and Frank Stratmann
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
We present the abundance and origin of cloud-relevant aerosol particles in the preindustral-like conditions of the Southern Ocean (SO) during Austral summer. Cloud condensation nuclei (CCN) and ice nucleating particles (INP) were measured during a circum-Antarctic scientific cruise with in situ instrumentation and offline filter measurements, respectively. Transport processes were found to play an equally important role as local sources for both the CCN and INP population of the SO.
Vaios Moschos, Martin Gysel-Beer, Robin L. Modini, Joel C. Corbin, Dario Massabò, Camilla Costa, Silvia G. Danelli, Athanasia Vlachou, Kaspar R. Daellenbach, Sönke Szidat, Paolo Prati, André S. H. Prévôt, Urs Baltensperger, and Imad El Haddad
Atmos. Chem. Phys., 21, 12809–12833,Short summary
This study provides a holistic approach to studying the spectrally resolved light absorption by atmospheric brown carbon (BrC) and black carbon using long time series of daily samples from filter-based measurements. The obtained results provide (1) a better understanding of the aerosol absorption profile and its dependence on BrC and on lensing from less absorbing coatings and (2) an estimation of the most important absorbers at typical European locations.
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,Short summary
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.
Ernesto Reyes-Villegas, Upasana Panda, Eoghan Darbyshire, James M. Cash, Rutambhara Joshi, Ben Langford, Chiara F. Di Marco, Neil J. Mullinger, Mohammed S. Alam, Leigh R. Crilley, Daniel J. Rooney, W. Joe F. Acton, Will Drysdale, Eiko Nemitz, Michael Flynn, Aristeidis Voliotis, Gordon McFiggans, Hugh Coe, James Lee, C. Nicholas Hewitt, Mathew R. Heal, Sachin S. Gunthe, Tuhin K. Mandal, Bhola R. Gurjar, Shivani, Ranu Gadi, Siddhartha Singh, Vijay Soni, and James D. Allan
Atmos. Chem. Phys., 21, 11655–11667,Short summary
This paper shows the first multisite online measurements of PM1 in Delhi, India, with measurements over different seasons in Old Delhi and New Delhi in 2018. Organic aerosol (OA) source apportionment was performed using positive matrix factorisation (PMF). Traffic was the main primary aerosol source for both OAs and black carbon, seen with PMF and Aethalometer model analysis, indicating that control of primary traffic exhaust emissions would make a significant reduction to Delhi air pollution.
Cyril Brunner, Benjamin Tobias Brem, Martine Collaud Coen, Franz Conen, Maxime Hervo, Stephan Henne, Martin Steinbacher, Martin Gysel-Beer, and Zamin Abdulali Kanji
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Special microscopic particles called ice-nucleating particles (INPs) are essential for ice crystals to form in the atmosphere. INPs are sparse and their atmospheric concentration and properties are not well understood. Mineral dust particles make up a significant fraction of INPs, but how much remains unknown. Here, we address this knowledge gap by studying periods when mineral particles are present in large quantities at a mountain top station in central Europe.
Hengheng Zhang, Frank Wagner, Harald Saathoff, Heike Vogel, Gholam Ali Hoshyaripour, Vanessa Bachmann, Jochen Förstner, and Thomas Leisner
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
The evolution and the properties of Saharan dust plume were characterized by LIDARs, a sun photometer, and a regional transport model. Comparison between LIDAR measurements, sun photometer and ICON-ART predictions shows a good agreement for dust arrival time, dust layer height, and dust structure but also that the model overestimates the backscatter coefficients by a factor of (2.2 ± 0.16) and underestimate aerosol optical depth by a factor of (1.5 ± 0.11).
Benjamin A. Nault, Duseong S. Jo, Brian C. McDonald, Pedro Campuzano-Jost, Douglas A. Day, Weiwei Hu, Jason C. Schroder, James Allan, Donald R. Blake, Manjula R. Canagaratna, Hugh Coe, Matthew M. Coggon, Peter F. DeCarlo, Glenn S. Diskin, Rachel Dunmore, Frank Flocke, Alan Fried, Jessica B. Gilman, Georgios Gkatzelis, Jacqui F. Hamilton, Thomas F. Hanisco, Patrick L. Hayes, Daven K. Henze, Alma Hodzic, James Hopkins, Min Hu, L. Greggory Huey, B. Thomas Jobson, William C. Kuster, Alastair Lewis, Meng Li, Jin Liao, M. Omar Nawaz, Ilana B. Pollack, Jeffrey Peischl, Bernhard Rappenglück, Claire E. Reeves, Dirk Richter, James M. Roberts, Thomas B. Ryerson, Min Shao, Jacob M. Sommers, James Walega, Carsten Warneke, Petter Weibring, Glenn M. Wolfe, Dominique E. Young, Bin Yuan, Qiang Zhang, Joost A. de Gouw, and Jose L. Jimenez
Atmos. Chem. Phys., 21, 11201–11224,Short summary
Secondary organic aerosol (SOA) is an important aspect of poor air quality for urban regions around the world, where a large fraction of the population lives. However, there is still large uncertainty in predicting SOA in urban regions. Here, we used data from 11 urban campaigns and show that the variability in SOA production in these regions is predictable and is explained by key emissions. These results are used to estimate the premature mortality associated with SOA in urban regions.
Barbara Bertozzi, Robert Wagner, Junwei Song, Kristina Höhler, Joschka Pfeifer, Harald Saathoff, Thomas Leisner, and Ottmar Möhler
Atmos. Chem. Phys., 21, 10779–10798,Short summary
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.
Zainab Bibi, Hugh Coe, James Brooks, Paul I. Williams, Ernesto Reyes-Villegas, Michael Priestley, Carl J. Percival, and James D. Allan
Atmos. Chem. Phys., 21, 10763–10777,Short summary
We are presenting a new method to apportion black carbon/soot into multiple sources through the inclusion of fullerene and metal data into HR-SP-AMS factorisation. While this itself would be considered a technical development, we can present a budget of contributions to measured BC during the event studied, including the conclusion that fireworks contributed little compared to the bonfire, traffic, and domestic wood-burning emissions.
James M. Cash, Ben Langford, Chiara Di Marco, Neil J. Mullinger, James Allan, Ernesto Reyes-Villegas, Ruthambara Joshi, Mathew R. Heal, W. Joe F. Acton, C. Nicholas Hewitt, Pawel K. Misztal, Will Drysdale, Tuhin K. Mandal, Shivani, Ranu Gadi, Bhola Ram Gurjar, and Eiko Nemitz
Atmos. Chem. Phys., 21, 10133–10158,Short summary
We present the first real-time composition of submicron particulate matter (PM1) in Old Delhi using high-resolution aerosol mass spectrometry. Seasonal analysis shows peak concentrations occur during the post-monsoon, and novel-tracers reveal the largest sources are a combination of local open and regional crop residue burning. Strong links between increased chloride aerosol concentrations and burning sources of PM1 suggest burning sources are responsible for the post-monsoon chloride peak.
Lucía Caudillo, Birte Rörup, Martin Heinritzi, Guillaume Marie, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Antonio Amorim, Farnoush Ataei, Rima Baalbaki, Barbara Bertozzi, Zoé Brasseur, Randall Chiu, Biwu Chu, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Loïc Gonzalez Carracedo, Xu-Cheng He, Victoria Hofbauer, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Brandon Lopez, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Dario Massabò, Roy L. Mauldin, Bernhard Mentler, Ugo Molteni, Antti Onnela, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Meredith Schervish, Wiebke Scholz, Benjamin Schulze, Jiali Shen, Dominik Stolzenburg, Yuri Stozhkov, Mihnea Surdu, Christian Tauber, Yee Jun Tham, Ping Tian, António Tomé, Steffen Vogt, Mingyi Wang, Dongyu S. Wang, Stefan K. Weber, André Welti, Wang Yonghong, Wu Yusheng, Marcel Zauner-Wieczorek, Urs Baltensperger, Imad El Haddad, Richard C. Flagan, Armin Hansel, Kristina Höhler, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Ottmar Möhler, Harald Saathoff, Rainer Volkamer, Paul M. Winkler, Neil M. Donahue, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
We performed experiments in the CLOUD chamber at CERN at low temperatures to simulate new particle formation in the upper free troposphere (at −30 °C and −50 °C). We measured particle and gas phase and found that most of the compounds that are present in the gas phase are detected as well in the particle phase. The major compounds in the particles are C8-10 and C18-20. Specifically, we showed that C5 and C15 compounds are detected in a mixed system with isoprene and α-pinene at −30 °C, 20 % RH.
Huihui Wu, Jonathan W. Taylor, Justin M. Langridge, Chenjie Yu, James D. Allan, Kate Szpek, Michael I. Cotterell, Paul I. Williams, Michael Flynn, Patrick Barker, Cathryn Fox, Grant Allen, James Lee, and Hugh Coe
Atmos. Chem. Phys., 21, 9417–9440,Short summary
Seasonal biomass burning over West Africa is a globally significant source of carbonaceous particles in the atmosphere, which have important climate impacts but are poorly constrained. We conducted in situ airborne measurements to investigate the evolution of smoke aerosol properties in this region. We observed absorption enhancement for both black carbon and brown carbon after emission, which provides new field results and constraints on aerosol parameterizations for future climate models.
Marco Zanatta, Andreas Herber, Zsófia Jurányi, Oliver Eppers, Johannes Schneider, and Joshua P. Schwarz
Atmos. Chem. Phys., 21, 9329–9342,Short summary
Saline snow samples were collected from the sea ice in the Fram Strait. Laboratory experiments revealed that sea salt can bias the quantification of black carbon with a laser-induced incandescence technique. The maximum underestimation was quantified to reach values of 80 %–90 %. This salt-induced interference is reported here for the first time and should be considered in future studies aiming to quantify black carbon in snow in marine environments.
Sobhan Kumar Kompalli, Surendran Nair Suresh Babu, Krishnaswamy Krishna Moorthy, Sreedharan Krishnakumari Satheesh, Mukunda Madhab Gogoi, Vijayakumar S. Nair, Venugopalan Nair Jayachandran, Dantong Liu, Michael J. Flynn, and Hugh Coe
Atmos. Chem. Phys., 21, 9173–9199,Short summary
The first observations of refractory black carbon aerosol size distributions and mixing state in South Asian outflow to the northern Indian Ocean were carried out as a part of the ICARB-2018 experiment during winter. Size distributions indicated mixed sources of BC particles in the outflow, which are thickly coated. The coating thickness of BC is controlled mainly by the availability of condensable species in the outflow.
Larissa Lacher, Hans-Christian Clemen, Xiaoli Shen, Stephan Mertes, Martin Gysel-Beer, Alireza Moallemi, Martin Steinbacher, Stephan Henne, Harald Saathoff, Ottmar Möhler, Kristina Höhler, Thea Schiebel, Daniel Weber, Jann Schrod, Johannes Schneider, and Zamin A. Kanji
Atmos. Chem. Phys. Discuss.,
Revised manuscript under review for ACPShort summary
We investigate ice-nucleating particle properties at Jungfraujoch during the joint INUIT/CLACE 2017 field campaign, to improve the knowledge about those rare particles in a cloud-relevant environment. By quantifying ice-nucleating particles in parallel to single-particle mass spectrometry measurements, we find that mineral dust and aged sea spray particles are potential candidates for ice-nucleating particles. Our findings are supported by ice residual analysis and source region modelling.
Christina J. Williamson, Agnieszka Kupc, Andrew Rollins, Jan Kazil, Karl D. Froyd, Eric A. Ray, Daniel M. Murphy, Gregory P. Schill, Jeff Peischl, Chelsea Thompson, Ilann Bourgeois, Thomas B. Ryerson, Glenn S. Diskin, Joshua P. DiGangi, Donald R. Blake, Thao Paul V. Bui, Maximilian Dollner, Bernadett Weinzierl, and Charles A. Brock
Atmos. Chem. Phys., 21, 9065–9088,Short summary
Aerosols in the stratosphere influence climate by scattering and absorbing sunlight and through chemical reactions occurring on the particles’ surfaces. We observed more nucleation mode aerosols (small aerosols, with diameters below 12 nm) in the mid- and high-latitude lowermost stratosphere (8–13 km) in the Northern Hemisphere (NH) than in the Southern Hemisphere. The most likely cause of this is aircraft emissions, which are concentrated in the NH at similar altitudes to our observations.
Mohanan R. Manoj, Sreedharan K. Satheesh, Krishnaswamy K. Moorthy, Jamie Trembath, and Hugh Coe
Atmos. Chem. Phys., 21, 8979–8997,Short summary
Vertical distributions of atmospheric aerosols across the Indo-Gangetic Plain (IGP) and their ability to form clouds have been studied based on airborne measurements during the SWAAMI field campaign. The ability of the aerosols to act as cloud-forming nuclei exhibited large spatial variation across the IGP and strong seasonality with increase in this ability with increase in altitude prior to the onset of monsoon and decrease with increase in altitude during the active phase of the monsoon.
Gian Lieberherr, Kevin Auderset, Bertrand Calpini, Bernard Clot, Benoît Crouzy, Martin Gysel-Beer, Thomas Konzelmann, José Manzano, Andrea Mihajlovic, Alireza Moallemi, David O'Connor, Branko Sikoparija, Eric Sauvageat, Fiona Tummon, and Konstantina Vasilatou
Atmos. Meas. Tech. Discuss.,
Revised manuscript under review for AMTShort summary
Today there is no standard procedure to validate bioaerosol and pollen monitors. Three instruments were tested, focusing on detecting particles of different sizes. Only one instrument was able to detect the smallest particles (0.5 µm Ø) whereas the others performed best at the largest tested particles (10 µm Ø). These results are the first step towards a standardized validation procedure. The need for a reference counting method for larger particles (pollen grains: 10–200 µm Ø) was emphasized.
Haoran Li, Ottmar Möhler, Tuukka Petäjä, and Dmitri Moisseev
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
In natural clouds, ice nucleating particles are expected to be rare above −10 °C. In the current manuscript, we found that the formation of ice columns is frequent in stratiform clouds and is associated with increased precipitation intensity and liquid water path. In single-layer shallow clouds, the produciton of ice columns were attributed to secondary ice production, despite that the rime-splintering process is not expected to take place in such clouds.
Theresa Haller, Eva Sommer, Thomas Steinkogler, Christian Rentenberger, Anna Wonaschuetz, Anne Kasper-Giebl, Hinrich Grothe, and Regina Hitzenberger
Atmos. Meas. Tech., 14, 3721–3735,Short summary
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.
Hongyu Guo, Pedro Campuzano-Jost, Benjamin A. Nault, Douglas A. Day, Jason C. Schroder, Dongwook Kim, Jack E. Dibb, Maximilian Dollner, Bernadett Weinzierl, and Jose L. Jimenez
Atmos. Meas. Tech., 14, 3631–3655,Short summary
We utilize a set of high-quality datasets collected during the NASA Atmospheric Tomography Mission to investigate the impact of differences in observable particle sizes across aerosol instruments in aerosol measurement comparisons. Very good agreement was found between chemically and physically derived submicron aerosol volume. Results support a lack of significant unknown biases in the response of an Aerodyne aerosol mass spectrometer (AMS) when sampling remote aerosols across the globe.
Dawei Hu, M. Rami Alfarra, Kate Szpek, Justin M. Langridge, Michael Cotterell, Claire Belcher, Ian Rule, Zixia Liu, Chenjie Yu, Yunqi Shao, Aristeidis Voliotis, Mao Du, Brett Smith, Greg Smallwood, Prem Lobo, Dantong Liu, Jim M. Haywood, Hugh Coe, and James D. Allan
Atmos. Chem. Phys. Discuss.,
Revised manuscript under review for ACPShort summary
Here, we developed new techniques for investigating these properties in the laboratory and applied these to BC and BrC from different sources, including diesel exhaust, inverted propane flame and wood combustion. These have allowed us to quantify the changes in shape and chemical composition of different soots according to source and variables such as the moisture content of wood.
Caroline C. Womack, Katherine M. Manfred, Nicholas L. Wagner, Gabriela Adler, Alessandro Franchin, Kara D. Lamb, Ann M. Middlebrook, Joshua P. Schwarz, Charles A. Brock, Steven S. Brown, and Rebecca A. Washenfelder
Atmos. Chem. Phys., 21, 7235–7252,Short summary
Microscopic particles interact with sunlight and affect the earth's climate in ways that are not fully understood. Aerosols from wildfire smoke present particular challenges due to their complexity in shape and composition. We demonstrate that we can experimentally measure aerosol optical properties for many types of smoke particles, using measurements of smoke from controlled burns, but that the method does not work well for smoke with high soot content.
Maria Kezoudi, Matthias Tesche, Helen Smith, Alexandra Tsekeri, Holger Baars, Maximilian Dollner, Víctor Estellés, Johannes Bühl, Bernadett Weinzierl, Zbigniew Ulanowski, Detlef Müller, and Vassilis Amiridis
Atmos. Chem. Phys., 21, 6781–6797,Short summary
Mineral dust concentrations in the diameter range from 0.4 to 14.0 μm were measured with the balloon-borne UCASS optical particle counter. Launches were coordinated with ground-based remote-sensing and airborne in situ measurements during a Saharan dust outbreak over Cyprus. Particle number concentrations reached 50 cm−3 for the diameter range 0.8–13.9 μm. Comparisons with aircraft data show reasonable agreement in magnitude and shape of the particle size distribution.
Fritz Waitz, Martin Schnaiter, Thomas Leisner, and Emma Järvinen
Atmos. Meas. Tech., 14, 3049–3070,Short summary
A major challenge in the observations of mixed-phase clouds remains the phase discrimination and sizing of cloud droplets and ice crystals, especially for particles with diameters smaller than 0.1 mm. Here, we present a new method to derive the phase and size of single cloud particles using their angular-light-scattering information. Comparisons with other in situ instruments in three case studies show good agreement.
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. Discuss.,
Revised manuscript accepted for ACPShort summary
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 cloud chamber with aqueous sulfuric acid aerosol, we provide a new empirical parameterization for homogeneous freezing onset conditions. The implementation of the new line in atmospheric models may have important implications on the cirrus cloud occurrence and related cloud radiative effects.
Manuel Baumgartner, Christian Rolf, Jens-Uwe Grooß, Julia Schneider, Tobias Schorr, Ottmar Möhler, Peter Spichtinger, and Martina Krämer
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
An important mechanism for the appearance of ice particles in the upper troposphere at low temperatures is homogeneous nucleation. This process is commonly described by the “Koop-line”, predicting the humidity at the freezing. However, laboratory measurements suggest that the freezing humidities are above the Koop-line, motivating the present study to investigate the influence of different physical parameterizations on the homogeneous freezing with the help of a detailed numerical model.
Robert Wagner, Luisa Ickes, Allan K. Bertram, Nora Els, Elena Gorokhova, Ottmar Möhler, Benjamin J. Murray, Nsikanabasi Silas Umo, and Matthew E. Salter
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Sea spray aerosol particles are a mixture of inorganic salts and organic matter from phytoplankton organisms. At low temperatures in the upper troposphere, both inorganic and organic constituents can induce the formation of ice crystals and thereby impact cloud properties and climate. In this study, we performed experiments in a cloud simulation chamber with particles produced from Arctic seawater samples to quantify the relative contribution of inorganic and organic species in ice formation.
Jessica Slater, Hugh Coe, Gordon McFiggans, Juha Tonttila, and Sami Romakkaniemi
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
This paper shows the specific impact of black carbon (BC) on the aerosol-planetary boundary layer (PBL) feedback and its influence on a Beijing haze episode. Overall, this paper shows that strong temperature inversions prevent BC heating within the PBL from significantly increasing PBL height, while BC above the PBL suppresses PBL development significantly through the day. From this we suggest a method by which both locally and regionally emitted BC may impact Beijing haze episodes.
Dalrin Ampritta Amaladhasan, Claudia Heyn, Christopher R. Hoyle, Imad El Haddad, Miriam Elser, Simone M. Pieber, Jay G. Slowik, Antonio Amorim, Jonathan Duplissy, Sebastian Ehrhart, Vladimir Makhmutov, Ugo Molteni, Matti Rissanen, Yuri Stozhkov, Robert Wagner, Armin Hansel, Jasper Kirkby, Neil M. Donahue, Rainer Volkamer, Urs Baltensperger, Martin Gysel-Beer, and Andreas Zuend
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
We employ a combination of models for gas-phase chemical reactions and equilibrium gas-particle partitioning of isoprene-derived secondary organic aerosols (SOA) informed by dark ozonolysis experiments conducted in the CLOUD chamber. Our predictions cover high to low relative humidities (RH) and quantify how SOA mass yields are enhanced at high RH as well as the impact of inorganic seeds of distinct hygroscopicities and acidities on the coupled partitioning of water and semivolatile organics.
Julia Schneider, Kristina Höhler, Paavo Heikkilä, Jorma Keskinen, Barbara Bertozzi, Pia Bogert, Tobias Schorr, Nsikanabasi Silas Umo, Franziska Vogel, Zoé Brasseur, Yusheng Wu, Simo Hakala, Jonathan Duplissy, Dmitri Moisseev, Markku Kulmala, Michael P. Adams, Benjamin J. Murray, Kimmo Korhonen, Liqing Hao, Erik S. Thomson, Dimitri Castarède, Thomas Leisner, Tuukka Petäjä, and Ottmar Möhler
Atmos. Chem. Phys., 21, 3899–3918,Short summary
By triggering the formation of ice crystals, ice-nucleating particles (INP) strongly influence cloud formation. Continuous, long-term measurements are needed to characterize the atmospheric INP variability. Here, a first long-term time series of INP spectra measured in the boreal forest for more than 1 year is presented, showing a clear seasonal cycle. It is shown that the seasonal dependency of INP concentrations and prevalent INP types is driven by the abundance of biogenic aerosol.
Robert Wagner, Baptiste Testa, Michael Höpfner, Alexei Kiselev, Ottmar Möhler, Harald Saathoff, Jörn Ungermann, and Thomas Leisner
Atmos. Meas. Tech., 14, 1977–1991,Short summary
During the Asian summer monsoon period, air pollutants are transported from layers near the ground to high altitudes of 13 to 18 km in the atmosphere. Infrared measurements have shown that particles composed of solid ammonium nitrate are a major part of these pollutants. To enable the quantitative analysis of the infrared spectra, we have determined for the first time accurate optical constants of ammonium nitrate for the low-temperature conditions of the upper atmosphere.
Michael Priestley, Thomas J. Bannan, Michael Le Breton, Stephen D. Worrall, Sungah Kang, Iida Pullinen, Sebastian Schmitt, Ralf Tillmann, Einhard Kleist, Defeng Zhao, Jürgen Wildt, Olga Garmash, Archit Mehra, Asan Bacak, Dudley E. Shallcross, Astrid Kiendler-Scharr, Åsa M. Hallquist, Mikael Ehn, Hugh Coe, Carl J. Percival, Mattias Hallquist, Thomas F. Mentel, and Gordon McFiggans
Atmos. Chem. Phys., 21, 3473–3490,Short summary
A significant fraction of emissions from human activity consists of aromatic hydrocarbons, e.g. benzene, which oxidise to form new compounds important for particle growth. Characterisation of benzene oxidation products highlights the range of species produced as well as their chemical properties and contextualises them within relevant frameworks, e.g. MCM. Cluster analysis of the oxidation product time series distinguishes behaviours of CHON compounds that could aid in identifying functionality.
Charles A. Brock, Karl D. Froyd, Maximilian Dollner, Christina J. Williamson, Gregory Schill, Daniel M. Murphy, Nicholas J. Wagner, Agnieszka Kupc, Jose L. Jimenez, Pedro Campuzano-Jost, Benjamin A. Nault, Jason C. Schroder, Douglas A. Day, Derek J. Price, Bernadett Weinzierl, Joshua P. Schwarz, Joseph M. Katich, Linghan Zeng, Rodney Weber, Jack Dibb, Eric Scheuer, Glenn S. Diskin, Joshua P. DiGangi, ThaoPaul Bui, Jonathan M. Dean-Day, Chelsea R. Thompson, Jeff Peischl, Thomas B. Ryerson, Ilann Bourgeois, Bruce C. Daube, Róisín Commane, and Steven C. Wofsy
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
The Atmospheric Tomography Mission was an airborne study that mapped the chemical composition of the remote atmosphere. From this, we developed a comprehensive description of aerosol properties that provides unique, global-scale dataset against which models can be compared. The data show the polluted nature of the remote atmosphere in the Northern Hemisphere, and quantify the contributions of sea salt, dust, soot, biomass burning particles, and pollution particles to the haziness of the sky.
Sebastian Düsing, Albert Ansmann, Holger Baars, Joel C. Corbin, Cyrielle Denjean, Martin Gysel-Beer, Thomas Müller, Laurent Poulain, Holger Siebert, Gerald Spindler, Thomas Tuch, Birgit Wehner, and Alfred Wiedensohler
Atmos. Chem. Phys. Discuss.,
Revised manuscript under review for ACPShort summary
The work deals with optical properties of aerosol particles in dried and atmospheric state. Based on two measurement campaigns in the rural background of Central Europe different measurement approaches were compared with each other, such as modeling based on Mie theory and direct in-situ or remote sensing measurements. Among others, it was shown that the aerosol extinction-to-backscatter ratio is relative humidity dependent, and refinement with respect to the model input parameters is needed.
Rosaria E. Pileci, Robin L. Modini, Michele Bertò, Jinfeng Yuan, Joel C. Corbin, Angela Marinoni, Bas Henzing, Marcel M. Moerman, Jean P. Putaud, Gerald Spindler, Birgit Wehner, Thomas Müller, Thomas Tuch, Arianna Trentini, Marco Zanatta, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Meas. Tech., 14, 1379–1403,Short summary
Black carbon (BC), which is an important constituent of atmospheric aerosols, remains difficult to quantify due to various limitations of available methods. This study provides an extensive comparison of co-located field measurements, applying two methods based on different principles. It was shown that both methods indeed quantify the same aerosol property – BC mass concentration. The level of agreement that can be expected was quantified, and some reasons for discrepancy were identified.
Jianzhong Sun, Yuzhe Zhang, Guorui Zhi, Regina Hitzenberger, Wenjing Jin, Yingjun Chen, Lei Wang, Chongguo Tian, Zhengying Li, Rong Chen, Wen Xiao, Yuan Cheng, Wei Yang, Liying Yao, Yang Cao, Duo Huang, Yueyuan Qiu, Jiali Xu, Xiaofei Xia, Xin Yang, Xi Zhang, Zheng Zong, Yuchun Song, and Changdong Wu
Atmos. Chem. Phys., 21, 2329–2341,Short summary
Brown carbon (BrC) emission factors from household biomass fuels were measured with an integrating sphere optics approach supported by iterative calculations. A novel algorithm to directly estimate the absorption contribution of BrC relative to that of BrC + black carbon (FBrC) was proposed based purely on the absorption exponent (AAE) (FBrC = 0.5519 lnAAE + 0.0067). The FBrC for household biomass fuels was as high as 50.8 % across the strongest solar spectral range of 350−850 nm.
Ottmar Möhler, Michael Adams, Larissa Lacher, Franziska Vogel, Jens Nadolny, Romy Ullrich, Cristian Boffo, Tatjana Pfeuffer, Achim Hobl, Maximilian Weiß, Hemanth S. K. Vepuri, Naruki Hiranuma, and Benjamin J. Murray
Atmos. Meas. Tech., 14, 1143–1166,Short summary
The Earth's climate is influenced by clouds, which are impacted by ice-nucleating particles (INPs), a minor fraction of atmospheric aerosols. INPs induce ice formation in clouds and thus often initiate precipitation formation. The Portable Ice Nucleation Experiment (PINE) is the first fully automated instrument to study cloud ice formation and to obtain long-term records of INPs. This is a timely development, and the capabilities it offers for research and atmospheric monitoring are significant.
Lisa K. Whalley, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Archit Mehra, Stephen D. Worrall, Asan Bacak, Thomas J. Bannan, Hugh Coe, Carl J. Percival, Bin Ouyang, Roderic L. Jones, Leigh R. Crilley, Louisa J. Kramer, William J. Bloss, Tuan Vu, Simone Kotthaus, Sue Grimmond, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 21, 2125–2147,Short summary
To understand how emission controls will impact ozone, an understanding of the sources and sinks of OH and the chemical cycling between peroxy radicals is needed. This paper presents measurements of OH, HO2 and total RO2 taken in central Beijing. The radical observations are compared to a detailed chemistry model, which shows that under low NO conditions, there is a missing OH source. Under high NOx conditions, the model under-predicts RO2 and impacts our ability to model ozone.
Mike J. Newland, Daniel J. Bryant, Rachel E. Dunmore, Thomas J. Bannan, W. Joe F. Acton, Ben Langford, James R. Hopkins, Freya A. Squires, William Dixon, William S. Drysdale, Peter D. Ivatt, Mathew J. Evans, Peter M. Edwards, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, C. Nicholas Hewitt, James D. Lee, Tianqu Cui, Jason D. Surratt, Xinming Wang, Alastair C. Lewis, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 21, 1613–1625,Short summary
We report the formation of secondary pollutants in the urban megacity of Beijing that are typically associated with remote regions such as rainforests. This is caused by extremely low levels of nitric oxide (NO), typically expected to be high in urban areas, observed in the afternoon. This work has significant implications for how we understand atmospheric chemistry in the urban environment and thus for how to implement effective policies to improve urban air quality.
Rob L. Modini, Joel C. Corbin, Benjamin T. Brem, Martin Irwin, Michele Bertò, Rosaria E. Pileci, Prodromos Fetfatzis, Kostas Eleftheriadis, Bas Henzing, Marcel M. Moerman, Fengshan Liu, Thomas Müller, and Martin Gysel-Beer
Atmos. Meas. Tech., 14, 819–851,Short summary
Extinction-minus-scattering is an important method for measuring aerosol light absorption, but its application in the field presents a number of challenges. A recently developed instrument based on this method – the CAPS PMssa – has the potential to overcome some of these challenges. We present a compilation of theory, lab measurements, and field examples to characterize this instrument and show the conditions under which it can deliver reliable absorption measurements for atmospheric aerosols.
Jim M. Haywood, Steven J. Abel, Paul A. Barrett, Nicolas Bellouin, Alan Blyth, Keith N. Bower, Melissa Brooks, Ken Carslaw, Haochi Che, Hugh Coe, Michael I. Cotterell, Ian Crawford, Zhiqiang Cui, Nicholas Davies, Beth Dingley, Paul Field, Paola Formenti, Hamish Gordon, Martin de Graaf, Ross Herbert, Ben Johnson, Anthony C. Jones, Justin M. Langridge, Florent Malavelle, Daniel G. Partridge, Fanny Peers, Jens Redemann, Philip Stier, Kate Szpek, Jonathan W. Taylor, Duncan Watson-Parris, Robert Wood, Huihui Wu, and Paquita Zuidema
Atmos. Chem. Phys., 21, 1049–1084,Short summary
Every year, the seasonal cycle of biomass burning from agricultural practices in Africa creates a huge plume of smoke that travels many thousands of kilometres over the Atlantic Ocean. This study provides an overview of a measurement campaign called the cloud–aerosol–radiation interaction and forcing for year 2017 (CLARIFY-2017) and documents the rationale, deployment strategy, observations, and key results from the campaign which utilized the heavily equipped FAAM atmospheric research aircraft.
Jinfeng Yuan, Robin Lewis Modini, Marco Zanatta, Andreas B. Herber, Thomas Müller, Birgit Wehner, Laurent Poulain, Thomas Tuch, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Chem. Phys., 21, 635–655,Short summary
Black carbon (BC) aerosols contribute substantially to climate warming due to their unique light absorption capabilities. We performed field measurements at a central European background site in winter and found that variability in the absorption efficiency of BC particles is driven mainly by their internal mixing state. Our results suggest that, at this site, knowing the BC mixing state is sufficient to describe BC light absorption enhancements due to the lensing effect in good approximation.
Rutambhara Joshi, Dantong Liu, Eiko Nemitz, Ben Langford, Neil Mullinger, Freya Squires, James Lee, Yunfei Wu, Xiaole Pan, Pingqing Fu, Simone Kotthaus, Sue Grimmond, Qiang Zhang, Ruili Wu, Oliver Wild, Michael Flynn, Hugh Coe, and James Allan
Atmos. Chem. Phys., 21, 147–162,Short summary
Black carbon (BC) is a component of particulate matter which has significant effects on climate and human health. Sources of BC include biomass burning, transport, industry and domestic cooking and heating. In this study, we measured BC emissions in Beijing, finding a dominance of traffic emissions over all other sources. The quantitative method presented here has benefits for revising widely used emissions inventories and for understanding BC sources with impacts on air quality and climate.
Clémence Rose, Martine Collaud Coen, Elisabeth Andrews, Yong Lin, Isaline Bossert, Cathrine Lund Myhre, Thomas Tuch, Alfred Wiedensohler, Markus Fiebig, Pasi Aalto, Andrés Alastuey, Elisabeth Alonso-Blanco, Marcos Andrade, Begoña Artíñano, Todor Arsov, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Juan Andrés Casquero-Vera, Sébastien Conil, Konstantinos Eleftheriadis, Olivier Favez, Harald Flentje, Maria I. Gini, Francisco Javier Gómez-Moreno, Martin Gysel-Beer, A. Gannet Hallar, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Neng-Huei Lin, Hassan Lyamani, Angela Marinoni, Sebastiao Martins Dos Santos, Olga L. Mayol-Bracero, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Jakub Ondracek, Marco Pandolfi, Noemi Pérez, Tuukka Petäjä, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Jean-Philippe Putaud, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Junying Sun, Pierre Tulet, Ville Vakkari, Pieter Gideon van Zyl, Fernando Velarde, Paolo Villani, Stergios Vratolis, Zdenek Wagner, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Vladimir Zdimal, and Paolo Laj
Atmos. Chem. Phys. Discuss.,
Preprint under review for ACPShort summary
Aerosol particles are a complex component of the atmospheric system which effects are among the most uncertain in climate change projections. Using data collected at 62 stations, this study provides the most up-to-date picture of the spatial distribution of particle number concentration and size distribution worldwide, with the aim of contributing to better representation of aerosols and their interactions with clouds in models and, therefore, better evaluation of their impact on climate.
Patrick A. Barker, Grant Allen, Martin Gallagher, Joseph R. Pitt, Rebecca E. Fisher, Thomas Bannan, Euan G. Nisbet, Stéphane J.-B. Bauguitte, Dominika Pasternak, Samuel Cliff, Marina B. Schimpf, Archit Mehra, Keith N. Bower, James D. Lee, Hugh Coe, and Carl J. Percival
Atmos. Chem. Phys., 20, 15443–15459,Short summary
Africa is estimated to account for approximately 52 % of global biomass burning (BB) carbon emissions. Despite this, there has been little previous in situ study of African BB emissions. This work presents BB emission factors for various atmospheric trace gases sampled from an aircraft in two distinct areas of Africa (Senegal and Uganda). Intracontinental variability in biomass burning methane emission is identified, which is attributed to difference in the specific fuel mixtures burnt.
Gourihar Kulkarni, Naruki Hiranuma, Ottmar Möhler, Kristina Höhler, Swarup China, Daniel J. Cziczo, and Paul J. DeMott
Atmos. Meas. Tech., 13, 6631–6643,Short summary
This study presents a new continuous-flow-diffusion-chamber-style operated ice chamber (Modified Compact Ice Chamber, MCIC) to measure the immersion-freezing efficiency of atmospheric particles. MCIC allowed us to obtain maximum droplet-freezing efficiency at higher time resolution without droplet breakthrough ambiguity. Its evaluation was performed by reproducing published data from the recent ice nucleation workshop and past laboratory data for standard and airborne ice-nucleating particles.
Agnieszka Kupc, Christina J. Williamson, Anna L. Hodshire, Jan Kazil, Eric Ray, T. Paul Bui, Maximilian Dollner, Karl D. Froyd, Kathryn McKain, Andrew Rollins, Gregory P. Schill, Alexander Thames, Bernadett B. Weinzierl, Jeffrey R. Pierce, and Charles A. Brock
Atmos. Chem. Phys., 20, 15037–15060,Short summary
Tropical upper troposphere over the Atlantic and Pacific oceans is a major source region of new particles. These particles are associated with the outflow from deep convection. We investigate the processes that govern the formation of these particles and their initial growth and show that none of the formation schemes commonly used in global models are consistent with observations. Using newer schemes indicates that organic compounds are likely important as nucleating and initial growth agents.
Douglas Morrison, Ian Crawford, Nicholas Marsden, Michael Flynn, Katie Read, Luis Neves, Virginia Foot, Paul Kaye, Warren Stanley, Hugh Coe, David Topping, and Martin Gallagher
Atmos. Chem. Phys., 20, 14473–14490,Short summary
We provide conservative estimates of the concentrations of bacteria within transatlantic dust clouds, originating from the African continent. We observe significant seasonal differences in the overall concentrations of particles but no seasonal variation in the ratio between bacteria and dust. With bacteria contributing to ice formation at warmer temperatures than dust, our observations should improve the accuracy of climate models.
Naruki Hiranuma, Brent W. Auvermann, Franco Belosi, Jack Bush, Kimberly M. Cory, Romy Fösig, Dimitri Georgakopoulos, Kristina Höhler, Yidi Hou, Harald Saathoff, Gianni Santachiara, Xiaoli Shen, Isabelle Steinke, Nsikanabasi Umo, Hemanth S. K. Vepuri, Franziska Vogel, and Ottmar Möhler
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
This study presents that feedlot could be a constant source of atmospheric ice particles, which influence clouds, precipitation, and climate. About 50 % of feedlot ice particles were supermicron in diameter. They were heat tolerant and may be an important part of a regional aerosol-cloud interaction. Feedlot ice residuals were rich in organics and low in salts. No notable known ice-nucleating microorganisms were found in our feedlot samples. Their ice nucleation parameterization is provided.
Huihui Wu, Jonathan W. Taylor, Kate Szpek, Justin M. Langridge, Paul I. Williams, Michael Flynn, James D. Allan, Steven J. Abel, Joseph Pitt, Michael I. Cotterell, Cathryn Fox, Nicholas W. Davies, Jim Haywood, and Hugh Coe
Atmos. Chem. Phys., 20, 12697–12719,Short summary
Airborne measurements of highly aged biomass burning aerosols (BBAs) over the remote southeast Atlantic provide unique aerosol parameters for climate models. Our observations demonstrate the persistence of strongly absorbing BBAs across wide regions of the South Atlantic. We also found significant vertical variation in the single-scattering albedo of these BBAs, as a function of relative chemical composition and size. Aerosol properties in the marine BL are suggested to be separated from the FT.
Jessica Slater, Juha Tonttila, Gordon McFiggans, Paul Connolly, Sami Romakkaniemi, Thomas Kühn, and Hugh Coe
Atmos. Chem. Phys., 20, 11893–11906,Short summary
The feedback effect between aerosol particles, radiation and meteorology reduces turbulent motion and results in increased surface aerosol concentrations during Beijing haze. Observational analysis and regional modelling studies have examined the feedback effect but these studies are limited. In this work, we set up a high-resolution model for the Beijing environment to examine the sensitivity of the aerosol feedback effect to initial meteorological conditions and aerosol loading.
Isabelle Steinke, Naruki Hiranuma, Roger Funk, Kristina Höhler, Nadine Tüllmann, Nsikanabasi Silas Umo, Peter G. Weidler, Ottmar Möhler, and Thomas Leisner
Atmos. Chem. Phys., 20, 11387–11397,Short summary
In this study, we highlight the potential impact of particles from certain terrestrial sources on the formation of ice crystals in clouds. In particular, we focus on biogenic particles consisting of various organic compounds, which makes it very difficult to predict the ice nucleation properties of complex ambient particles. We find that these ambient particles are often more ice active than individual components.
Jonathan W. Taylor, Huihui Wu, Kate Szpek, Keith Bower, Ian Crawford, Michael J. Flynn, Paul I. Williams, James Dorsey, Justin M. Langridge, Michael I. Cotterell, Cathryn Fox, Nicholas W. Davies, Jim M. Haywood, and Hugh Coe
Atmos. Chem. Phys., 20, 11201–11221,Short summary
Every year, huge plumes of smoke hundreds of miles wide travel over the south Atlantic Ocean from fires in central and southern Africa. These plumes absorb the sun’s energy and warm the climate. We used airborne optical instrumentation to determine how absorbing the smoke was as well as the relative importance of black and brown carbon. We also tested different ways of simulating these properties that could be used in a climate model.
Luisa Ickes, Grace C. E. Porter, Robert Wagner, Michael P. Adams, Sascha Bierbauer, Allan K. Bertram, Merete Bilde, Sigurd Christiansen, Annica M. L. Ekman, Elena Gorokhova, Kristina Höhler, Alexei A. Kiselev, Caroline Leck, Ottmar Möhler, Benjamin J. Murray, Thea Schiebel, Romy Ullrich, and Matthew E. Salter
Atmos. Chem. Phys., 20, 11089–11117,Short summary
The Arctic is a region where aerosols are scarce. Sea spray might be a potential source of aerosols acting as ice-nucleating particles. We investigate two common phytoplankton species (Melosira arctica and Skeletonema marinoi) and present their ice nucleation activity in comparison with Arctic seawater microlayer samples from different field campaigns. We also aim to understand the aerosolization process of marine biological samples and the potential effect on the ice nucleation activity.
Hamish Gordon, Paul R. Field, Steven J. Abel, Paul Barrett, Keith Bower, Ian Crawford, Zhiqiang Cui, Daniel P. Grosvenor, Adrian A. Hill, Jonathan Taylor, Jonathan Wilkinson, Huihui Wu, and Ken S. Carslaw
Atmos. Chem. Phys., 20, 10997–11024,Short summary
The Met Office's Unified Model is widely used both for weather forecasting and climate prediction. We present the first version of the model in which both aerosol and cloud particle mass and number concentrations are allowed to evolve separately and independently, which is important for studying how aerosols affect weather and climate. We test the model against aircraft observations near Ascension Island in the Atlantic, focusing on how aerosols can "activate" to become cloud droplets.
Archit Mehra, Jordan E. Krechmer, Andrew Lambe, Chinmoy Sarkar, Leah Williams, Farzaneh Khalaj, Alex Guenther, John Jayne, Hugh Coe, Douglas Worsnop, Celia Faiola, and Manjula Canagaratna
Atmos. Chem. Phys., 20, 10953–10965,Short summary
Emissions of volatile organic compounds (VOCs) from plants are important for tropospheric ozone and secondary organic aerosol (SOA) formation. Real plant emissions are much more diverse than the few proxies widely used for studies of plant SOA. Here we present the first study of SOA from Californian sage plants and the oxygenated monoterpenes representing their major emissions. We identify SOA products and show the importance of the formation of highly oxygenated organic molecules and oligomers.
Christof G. Beer, Johannes Hendricks, Mattia Righi, Bernd Heinold, Ina Tegen, Silke Groß, Daniel Sauer, Adrian Walser, and Bernadett Weinzierl
Geosci. Model Dev., 13, 4287–4303,Short summary
Mineral dust aerosol plays an important role in the climate system. Previously, dust emissions have often been represented in global models by prescribed monthly-mean emission fields representative of a specific year. We now apply an online calculation of wind-driven dust emissions. This results in an improved agreement with observations, due to a better representation of the highly variable dust emissions. Increasing the model resolution led to an additional performance gain.
David Topping, David Watts, Hugh Coe, James Evans, Thomas J. Bannan, Douglas Lowe, Caroline Jay, and Jonathan W. Taylor
Geosci. Model Dev. Discuss.,
Publication in GMD not foreseenShort summary
Time-series forecasting methods have often been used to mitigate some of the challenges associated with deploying chemical transport models. In this study we deploy and evaluate Facebook’s Prophetmodel v0.6 in predicting hourly concentrations of Nitrogen Dioxide [NO2]. et. Overall we find the Prophet model offers a relatively effective and simple way to make predictions about NO2 at local levels.
Leighton A. Regayre, Julia Schmale, Jill S. Johnson, Christian Tatzelt, Andrea Baccarini, Silvia Henning, Masaru Yoshioka, Frank Stratmann, Martin Gysel-Beer, Daniel P. Grosvenor, and Ken S. Carslaw
Atmos. Chem. Phys., 20, 10063–10072,Short summary
The amount of energy reflected back into space because of man-made particles is highly uncertain. Processes related to naturally occurring particles cause most of the uncertainty, but these processes are poorly constrained by present-day measurements. We show that measurements over the Southern Ocean, far from pollution sources, efficiently reduce climate model uncertainties. Our results pave the way to designing experiments and measurement campaigns that reduce this uncertainty even further.
Archit Mehra, Yuwei Wang, Jordan E. Krechmer, Andrew Lambe, Francesca Majluf, Melissa A. Morris, Michael Priestley, Thomas J. Bannan, Daniel J. Bryant, Kelly L. Pereira, Jacqueline F. Hamilton, Andrew R. Rickard, Mike J. Newland, Harald Stark, Philip Croteau, John T. Jayne, Douglas R. Worsnop, Manjula R. Canagaratna, Lin Wang, and Hugh Coe
Atmos. Chem. Phys., 20, 9783–9803,Short summary
Aromatic volatile organic compounds (VOCs) emitted from anthropogenic activity are important for tropospheric ozone and secondary organic aerosol (SOA) formation. Here we present a detailed chemical characterisation of SOA from four C9-aromatic isomers and a polycyclic aromatic hydrocarbon (PAH). We identify and compare their oxidation products in the gas and particle phases, showing the different relative importance of oxidation pathways and proportions of highly oxygenated organic molecules.
Paolo Laj, Alessandro Bigi, Clémence Rose, Elisabeth Andrews, Cathrine Lund Myhre, Martine Collaud Coen, Yong Lin, Alfred Wiedensohler, Michael Schulz, John A. Ogren, Markus Fiebig, Jonas Gliß, Augustin Mortier, Marco Pandolfi, Tuukka Petäja, Sang-Woo Kim, Wenche Aas, Jean-Philippe Putaud, Olga Mayol-Bracero, Melita Keywood, Lorenzo Labrador, Pasi Aalto, Erik Ahlberg, Lucas Alados Arboledas, Andrés Alastuey, Marcos Andrade, Begoña Artíñano, Stina Ausmeel, Todor Arsov, Eija Asmi, John Backman, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Sébastien Conil, Cedric Couret, Derek Day, Wan Dayantolis, Anna Degorska, Konstantinos Eleftheriadis, Prodromos Fetfatzis, Olivier Favez, Harald Flentje, Maria I. Gini, Asta Gregorič, Martin Gysel-Beer, A. Gannet Hallar, Jenny Hand, Andras Hoffer, Christoph Hueglin, Rakesh K. Hooda, Antti Hyvärinen, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Jeong Eun Kim, Giorgos Kouvarakis, Irena Kranjc, Radovan Krejci, Markku Kulmala, Casper Labuschagne, Hae-Jung Lee, Heikki Lihavainen, Neng-Huei Lin, Gunter Löschau, Krista Luoma, Angela Marinoni, Sebastiao Martins Dos Santos, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Nhat Anh Nguyen, Jakub Ondracek, Noemi Pérez, Maria Rita Perrone, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Natalia Prats, Anthony Prenni, Fabienne Reisen, Salvatore Romano, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Maik Schütze, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Martin Steinbacher, Junying Sun, Gloria Titos, Barbara Toczko, Thomas Tuch, Pierre Tulet, Peter Tunved, Ville Vakkari, Fernando Velarde, Patricio Velasquez, Paolo Villani, Sterios Vratolis, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Jesus Yus-Diez, Vladimir Zdimal, Paul Zieger, and Nadezda Zikova
Atmos. Meas. Tech., 13, 4353–4392,Short summary
The paper establishes the fiducial reference of the GAW aerosol network providing the fully characterized value chain to the provision of four climate-relevant aerosol properties from ground-based sites. Data from almost 90 stations worldwide are reported for a reference year, 2017, providing a unique and very robust view of the variability of these variables worldwide. Current gaps in the GAW network are analysed and requirements for the Global Climate Monitoring System are proposed.
Yuwei Wang, Archit Mehra, Jordan E. Krechmer, Gan Yang, Xiaoyu Hu, Yiqun Lu, Andrew Lambe, Manjula Canagaratna, Jianmin Chen, Douglas Worsnop, Hugh Coe, and Lin Wang
Atmos. Chem. Phys., 20, 9563–9579,Short summary
A series of OH-initiated oxidation experiments of trimethylbenzene were investigated in the absence and presence of NOx. Many C9 products with 1–11 oxygen atoms and C18 products presumably formed from dimerization of C9 peroxy radicals were observed, hinting at the extensive existence of autoxidation and accretion reaction pathways. The presence of NOx would suppress the formation of highly oxygenated C18 molecules and enhance the formation of organonitrates and even dinitrate compounds.
Jill S. Johnson, Leighton A. Regayre, Masaru Yoshioka, Kirsty J. Pringle, Steven T. Turnock, Jo Browse, David M. H. Sexton, John W. Rostron, Nick A. J. Schutgens, Daniel G. Partridge, Dantong Liu, James D. Allan, Hugh Coe, Aijun Ding, David D. Cohen, Armand Atanacio, Ville Vakkari, Eija Asmi, and Ken S. Carslaw
Atmos. Chem. Phys., 20, 9491–9524,Short summary
We use over 9000 monthly aggregated grid-box measurements of aerosol to constrain the uncertainty in the HadGEM3-UKCA climate model. Measurements of AOD, PM2.5, particle number concentrations, sulfate and organic mass concentrations are compared to 1 million
variantsof the model using an implausibility metric. Despite many compensating effects in the model, the procedure constrains the probability distributions of many parameters, and direct radiative forcing uncertainty is reduced by 34 %.
Martine Collaud Coen, Elisabeth Andrews, Andrés Alastuey, Todor Petkov Arsov, John Backman, Benjamin T. Brem, Nicolas Bukowiecki, Cédric Couret, Konstantinos Eleftheriadis, Harald Flentje, Markus Fiebig, Martin Gysel-Beer, Jenny L. Hand, András Hoffer, Rakesh Hooda, Christoph Hueglin, Warren Joubert, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Casper Labuschagne, Neng-Huei Lin, Yong Lin, Cathrine Lund Myhre, Krista Luoma, Hassan Lyamani, Angela Marinoni, Olga L. Mayol-Bracero, Nikos Mihalopoulos, Marco Pandolfi, Natalia Prats, Anthony J. Prenni, Jean-Philippe Putaud, Ludwig Ries, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Patrick Sheridan, James Patrick Sherman, Junying Sun, Gloria Titos, Elvis Torres, Thomas Tuch, Rolf Weller, Alfred Wiedensohler, Paul Zieger, and Paolo Laj
Atmos. Chem. Phys., 20, 8867–8908,Short summary
Long-term trends of aerosol radiative properties (52 stations) prove that aerosol load has significantly decreased over the last 20 years. Scattering trends are negative in Europe (EU) and North America (NA), not ss in Asia, and show a mix of positive and negative trends at polar stations. Absorption has mainly negative trends. The single scattering albedo has positive trends in Asia and eastern EU and negative in western EU and NA, leading to a global positive median trend of 0.02 % per year.
Sebastian Landwehr, Iris Thurnherr, Nicolas Cassar, Martin Gysel-Beer, and Julia Schmale
Atmos. Meas. Tech., 13, 3487–3506,Short summary
Shipborne wind speed measurements are relevant for field studies of air–sea interaction processes. Distortion of the airflow by the ship’s structure can, however, lead to errors. We estimate the flow distortion bias by comparing the observations to ERA-5 reanalysis data. The underlying assumptions are that the bias depends only on the relative orientation of the ship to the wind direction and that the ERA-5 wind speeds are (on average) representative of the true wind speed.
Daniel J. Bryant, William J. Dixon, James R. Hopkins, Rachel E. Dunmore, Kelly L. Pereira, Marvin Shaw, Freya A. Squires, Thomas J. Bannan, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Bin Ouyang, Tianqu Cui, Jason D. Surratt, Di Liu, Zongbo Shi, Roy Harrison, Yele Sun, Weiqi Xu, Alastair C. Lewis, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 20, 7531–7552,Short summary
Using the chemical composition of offline filter samples, we report that a large share of oxidized organic aerosol in Beijing during summer is due to isoprene secondary organic aerosol (iSOA). iSOA organosulfates showed a strong correlation with the product of ozone and particulate sulfate. This highlights the role of both photochemistry and the availability of particulate sulfate in heterogeneous reactions and further demonstrates that iSOA formation is controlled by anthropogenic emissions.
Stefanos Samaras, Christine Böckmann, Moritz Haarig, Albert Ansmann, Adrian Walser, and Bernadett Weinzierl
Atmos. Chem. Phys. Discuss.,
Preprint withdrawnShort summary
We retrieve microphysical properties of Saharan dust particles after a long-range transport over the Atlantic Ocean to Barbados using three depolarization channels of a Raman lidar. The retrievals are performed with a spheroidal software tool by regularization. For the first time we retrieve simultaneously a shape- and size-dependent particle distribution and compare it with the polarization lidar-photometer networking method, ground-based photometer and airborne in situ particle counter data.
Pablo E. Saide, Meng Gao, Zifeng Lu, Daniel L. Goldberg, David G. Streets, Jung-Hun Woo, Andreas Beyersdorf, Chelsea A. Corr, Kenneth L. Thornhill, Bruce Anderson, Johnathan W. Hair, Amin R. Nehrir, Glenn S. Diskin, Jose L. Jimenez, Benjamin A. Nault, Pedro Campuzano-Jost, Jack Dibb, Eric Heim, Kara D. Lamb, Joshua P. Schwarz, Anne E. Perring, Jhoon Kim, Myungje Choi, Brent Holben, Gabriele Pfister, Alma Hodzic, Gregory R. Carmichael, Louisa Emmons, and James H. Crawford
Atmos. Chem. Phys., 20, 6455–6478,Short summary
Air quality forecasts over the Korean Peninsula captured aerosol optical depth but largely overpredicted surface PM during a Chinese haze transport event. Model deficiency was related to the calculation of optical properties. In order to improve it, aerosol size representation needs to be refined in the calculations, and the representation of aerosol properties, such as size distribution, chemical composition, refractive index, hygroscopicity parameter, and density, needs to be improved.
Sophia Brilke, Nikolaus Fölker, Thomas Müller, Konrad Kandler, Xianda Gong, Jeff Peischl, Bernadett Weinzierl, and Paul M. Winkler
Atmos. Chem. Phys., 20, 5645–5656,Short summary
Atmospheric particle size distributions with the focus on freshly nucleated particles were measured during the A-LIFE field experiment in Cyprus. A DMA-train was set up for the first time in an atmospheric environment and captures the sub-10 nm particle dynamics. Several new particle formation (NPF) events are studied in detail, of which some did not show particle growth beyond 10 nm indicating that NPF may occur more frequently than estimated when the sub-10 nm size range is not covered.
William T. Morgan, James D. Allan, Stéphane Bauguitte, Eoghan Darbyshire, Michael J. Flynn, James Lee, Dantong Liu, Ben Johnson, Jim Haywood, Karla M. Longo, Paulo E. Artaxo, and Hugh Coe
Atmos. Chem. Phys., 20, 5309–5326,Short summary
We flew a large atmospheric research aircraft across a number of different environments in the Amazon basin during the 2012 biomass burning season. Smoke from fires builds up and has a significant impact on weather, climate, health and natural ecosystems. Our goal was to quantify changes in the properties of the smoke emitted by fires as it is transported through the atmosphere. We found that the major control on the properties of the smoke was due to differences in the fires themselves.
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,Short summary
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,Short summary
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.
Alma Hodzic, Pedro Campuzano-Jost, Huisheng Bian, Mian Chin, Peter R. Colarco, Douglas A. Day, Karl D. Froyd, Bernd Heinold, Duseong S. Jo, Joseph M. Katich, John K. Kodros, Benjamin A. Nault, Jeffrey R. Pierce, Eric Ray, Jacob Schacht, Gregory P. Schill, Jason C. Schroder, Joshua P. Schwarz, Donna T. Sueper, Ina Tegen, Simone Tilmes, Kostas Tsigaridis, Pengfei Yu, and Jose L. Jimenez
Atmos. Chem. Phys., 20, 4607–4635,Short summary
Organic aerosol (OA) is a key source of uncertainty in aerosol climate effects. We present the first pole-to-pole OA characterization during the NASA Atmospheric Tomography aircraft mission. OA has a strong seasonal and zonal variability, with the highest levels in summer and over fire-influenced regions and the lowest ones in the southern high latitudes. We show that global models predict the OA distribution well but not the relative contribution of OA emissions vs. chemical production.
Antonio Spanu, Maximilian Dollner, Josef Gasteiger, T. Paul Bui, and Bernadett Weinzierl
Atmos. Meas. Tech., 13, 1963–1987,Short summary
This study investigates how the airflow around wing-mounted instruments on fast-flying aircraft affects aerosol and cloud measurements. It combines airborne data with numerical simulations and shows that particle speed, particle concentration, and shape of water droplets are modified by the airflow. The proposed correction strategy for optical particle counters and optical array probes considers airflow effects and significantly reduces errors of derived ambient aerosol and cloud properties.
Steven J. Abel, Paul A. Barrett, Paquita Zuidema, Jianhao Zhang, Matt Christensen, Fanny Peers, Jonathan W. Taylor, Ian Crawford, Keith N. Bower, and Michael Flynn
Atmos. Chem. Phys., 20, 4059–4084,Short summary
In situ measurements of a free-tropospheric (FT) biomass burning aerosol plume in contact with the boundary layer inversion overriding a pocket of open cells (POC) and surrounding stratiform cloud are presented. The data highlight the contrasting thermodynamic, aerosol and cloud properties in the two cloud regimes and further demonstrate that the cloud regime plays a key role in regulating the flow of FT aerosols into the boundary layer, which has implications for the aerosol indirect effect.
Sobhan Kumar Kompalli, Surendran Nair Suresh Babu, Sreedharan Krishnakumari Satheesh, Krishnaswamy Krishna Moorthy, Trupti Das, Ramasamy Boopathy, Dantong Liu, Eoghan Darbyshire, James D. Allan, James Brooks, Michael J. Flynn, and Hugh Coe
Atmos. Chem. Phys., 20, 3965–3985,
Mohanan R. Manoj, Sreedharan K. Satheesh, Krishnaswamy K. Moorthy, and Hugh Coe
Atmos. Chem. Phys., 20, 4031–4046,Short summary
The study reports the observation of highly absorbing aerosol layers at high altitudes (1–2.5 km) prior to monsoon and during its development over the Indian region and quantifies its climate impacts. The absorption of solar radiation in these layers perturbs the onset of monsoon through the impact on the atmospheric stability. When height-resolved values of single scattering albedo (SSA) are used in a radiative transfer model, a maximum heating ~1 K d (~twice that using SSA) is obtained.
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,Short summary
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.
Chenjie Yu, Dantong Liu, Kurtis Broda, Rutambhara Joshi, Jason Olfert, Yele Sun, Pingqing Fu, Hugh Coe, and James D. Allan
Atmos. Chem. Phys., 20, 3645–3661,Short summary
This study presents the first atmospheric application of a new morphology-independent measurement for the quantification of the mixing state of rBC-containing particles in urban Beijing as part of the UK–China APHH campaign. An inversion method has been applied for better quantification of rBC mixing state. The mass-resolved rBC mixing state information presented here has implications for detailed models of BC, its optical properties and its atmospheric life cycle.
Sidhant J. Pai, Colette L. Heald, Jeffrey R. Pierce, Salvatore C. Farina, Eloise A. Marais, Jose L. Jimenez, Pedro Campuzano-Jost, Benjamin A. Nault, Ann M. Middlebrook, Hugh Coe, John E. Shilling, Roya Bahreini, Justin H. Dingle, and Kennedy Vu
Atmos. Chem. Phys., 20, 2637–2665,Short summary
Aerosols in the atmosphere have significant health and climate impacts. Organic aerosol (OA) accounts for a large fraction of the total aerosol burden, but models have historically struggled to accurately simulate it. This study compares two very different OA model schemes and evaluates them against a suite of globally distributed airborne measurements with the goal of providing insight into the strengths and weaknesses of each approach across different environments.
Therese S. Carter, Colette L. Heald, Jose L. Jimenez, Pedro Campuzano-Jost, Yutaka Kondo, Nobuhiro Moteki, Joshua P. Schwarz, Christine Wiedinmyer, Anton S. Darmenov, Arlindo M. da Silva, and Johannes W. Kaiser
Atmos. Chem. Phys., 20, 2073–2097,Short summary
Fires and the smoke they emit impact air quality, health, and climate, but the abundance and properties of smoke remain uncertain and poorly constrained. To explore this, we compare model simulations driven by four commonly-used fire emission inventories with surface, aloft, and satellite observations. We show that across inventories smoke emissions differ by factors of 4 to 7 over North America, challenging our ability to accurately characterize the impact of smoke on air quality and climate.
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,Short summary
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.
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,Short summary
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.
Carmen Dameto de España, Anna Wonaschuetz, Gerhard Steiner, Harald Schuh, Constantinos Sioutas, and Regina Hitzenberger
Atmos. Meas. Tech. Discuss.,
Joel C. Corbin and Martin Gysel-Beer
Atmos. Chem. Phys., 19, 15673–15690,Short summary
We review the literature to refine the definition of "tar balls" (or tar particles). Then, using a marine-engine data set, we show that a standard SP2 can identify tar particles in two ways, as evaporating and non-incandescing (30 % of tar particles by number) or incandescing particles which scatter more light than soot at incandescence (70 % of tar particles by number). To our knowledge, no other technique can provide in situ, real-time evidence for the presence of tar particles in an aerosol.
Claire L. Ryder, Eleanor J. Highwood, Adrian Walser, Petra Seibert, Anne Philipp, and Bernadett Weinzierl
Atmos. Chem. Phys., 19, 15353–15376,Short summary
Mineral dust is lifted into the atmosphere from desert regions, where it can be transported over thousands of kilometres around the world. Dust impacts weather, climate, aviation, and air quality. We evaluate new aircraft observations of dust size. We find that the largest particles typically omitted by models have a significant impact on the interactions of dust with radiation and therefore climate. We also find that large dust particles are retained in the atmosphere longer than expected.
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,Short summary
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.
Leigh R. Crilley, Louisa J. Kramer, Bin Ouyang, Jun Duan, Wenqian Zhang, Shengrui Tong, Maofa Ge, Ke Tang, Min Qin, Pinhua Xie, Marvin D. Shaw, Alastair C. Lewis, Archit Mehra, Thomas J. Bannan, Stephen D. Worrall, Michael Priestley, Asan Bacak, Hugh Coe, James Allan, Carl J. Percival, Olalekan A. M. Popoola, Roderic L. Jones, and William J. Bloss
Atmos. Meas. Tech., 12, 6449–6463,Short summary
Nitrous acid (HONO) is key species for understanding tropospheric chemistry, yet accurate and precise measurements are challenging. Here we report an inter–comparison exercise of a number of instruments that measured HONO in a highly polluted location (Beijing). All instruments agreed on the temporal trends yet displayed divergence in absolute concentrations. The cause of this divergence was unclear, but it may in part be due to spatial variability in instrument location.
Carlos Toledano, Benjamín Torres, Cristian Velasco-Merino, Dietrich Althausen, Silke Groß, Matthias Wiegner, Bernadett Weinzierl, Josef Gasteiger, Albert Ansmann, Ramiro González, David Mateos, David Farrel, Thomas Müller, Moritz Haarig, and Victoria E. Cachorro
Atmos. Chem. Phys., 19, 14571–14583,Short summary
Ground-based sun photometers have been used to analyze the properties of long-range transported Saharan dust over Barbados. The measurements were carried out as part of the Saharan Aerosol Long-Range Transport and Aerosol–Cloud-Interaction Experiment (SALTRACE), carried out in the Caribbean in 2013. A variety of instruments, ground-based and airborne, were used in this research. In this paper, the sun photometer data are presented and related to data collected from other co-located instruments.
André Ehrlich, Manfred Wendisch, Christof Lüpkes, Matthias Buschmann, Heiko Bozem, Dmitri Chechin, Hans-Christian Clemen, Régis Dupuy, Olliver Eppers, Jörg Hartmann, Andreas Herber, Evelyn Jäkel, Emma Järvinen, Olivier Jourdan, Udo Kästner, Leif-Leonard Kliesch, Franziska Köllner, Mario Mech, Stephan Mertes, Roland Neuber, Elena Ruiz-Donoso, Martin Schnaiter, Johannes Schneider, Johannes Stapf, and Marco Zanatta
Earth Syst. Sci. Data, 11, 1853–1881,Short summary
During the Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) campaign, two research aircraft (Polar 5 and 6) jointly performed 22 research flights over the transition zone between open ocean and closed sea ice. The data set combines remote sensing and in situ measurement of cloud, aerosol, and trace gas properties, as well as turbulent and radiative fluxes, which will be used to study Arctic boundary layer and mid-level clouds and their role in Arctic amplification.
Moritz Haarig, Adrian Walser, Albert Ansmann, Maximilian Dollner, Dietrich Althausen, Daniel Sauer, David Farrell, and Bernadett Weinzierl
Atmos. Chem. Phys., 19, 13773–13788,Short summary
Aerosol particles are necessary in forming a cloud droplet. In order to improve studies of cloud formation, the aerosol load and type below a cloud has to be measured without disturbing the cloud. The lidar is a perfect tool for this purpose, as it provides a vertical profile of the aerosol particles from the ground. We validated the lidar retrieval of cloud-relevant aerosol properties like particle number concentrations with airborne in situ measurements in the Saharan Air Layer at Barbados.
Xiaoli Shen, Heike Vogel, Bernhard Vogel, Wei Huang, Claudia Mohr, Ramakrishna Ramisetty, Thomas Leisner, André S. H. Prévôt, and Harald Saathoff
Atmos. Chem. Phys., 19, 13189–13208,Short summary
This study provides good insight into the chemical nature and complex origin of aerosols by combining comprehensive field observations and transport modelling. We suggest that factors related to topography, metrological conditions, local emissions, in situ formation and growth, regional transport, and the interaction of biogenic and anthropogenic compounds need to be considered for a comprehensive understanding of aerosol processes.
James Brooks, Dantong Liu, James D. Allan, Paul I. Williams, Jim Haywood, Ellie J. Highwood, Sobhan K. Kompalli, S. Suresh Babu, Sreedharan K. Satheesh, Andrew G. Turner, and Hugh Coe
Atmos. Chem. Phys., 19, 13079–13096,Short summary
Our study presents an analysis of the vertical and horizontal black carbon properties across northern India using aircraft measurements. The Indo-Gangetic Plain saw the greatest black carbon mass concentrations during the pre-monsoon season. Two black carbon modes were recorded: a small black carbon mode (traffic emissions) in the north-west and a moderately coated mode (solid-fuel emissions) in the Indo-Gangetic Plain. In the vertical profile, absorption properties increase with height.
Duncan Watson-Parris, Nick Schutgens, Carly Reddington, Kirsty J. Pringle, Dantong Liu, James D. Allan, Hugh Coe, Ken S. Carslaw, and Philip Stier
Atmos. Chem. Phys., 19, 11765–11790,Short summary
The vertical distribution of aerosol in the atmosphere affects its ability to act as cloud condensation nuclei and changes the amount of sunlight it absorbs or reflects. Common global measurements of aerosol provide no information about this vertical distribution. Using a global collection of in situ aircraft measurements to compare with an aerosol–climate model (ECHAM-HAM), we explore the key processes controlling this distribution and find that wet removal plays a key role.
Wei Huang, Harald Saathoff, Xiaoli Shen, Ramakrishna Ramisetty, Thomas Leisner, and Claudia Mohr
Atmos. Chem. Phys., 19, 11687–11700,Short summary
We investigate the molecular composition and volatility of oxygenated organic aerosol (OOA) particles in summer and winter in Stuttgart, Germany. OOA in summer is more influenced by biogenic emissions, while in winter biomass burning emissions are an important source. OOA in winter is also less volatile. Potential reasons are discussed in our paper. Our study shows the important contributions of nonfossil OA from biogenic and biomass burning even in an urban area with high traffic emissions.
Carmen Dameto de España, Gerhard Steiner, Harald Schuh, Constantinos Sioutas, and Regina Hitzenberger
Atmos. Meas. Tech., 12, 4733–4744,
Jacob Schacht, Bernd Heinold, Johannes Quaas, John Backman, Ribu Cherian, Andre Ehrlich, Andreas Herber, Wan Ting Katty Huang, Yutaka Kondo, Andreas Massling, P. R. Sinha, Bernadett Weinzierl, Marco Zanatta, and Ina Tegen
Atmos. Chem. Phys., 19, 11159–11183,Short summary
The Arctic is warming faster than the rest of Earth. Black carbon (BC) aerosol contributes to this Arctic amplification by direct and indirect aerosol radiative effects while distributed in air or deposited on snow and ice. The aerosol-climate model ECHAM-HAM is used to estimate direct aerosol radiative effect (DRE). Airborne and near-surface BC measurements are used to evaluate the model and give an uncertainty range for the burden and DRE of Arctic BC caused by different emission inventories.
Xianda Gong, Heike Wex, Thomas Müller, Alfred Wiedensohler, Kristina Höhler, Konrad Kandler, Nan Ma, Barbara Dietel, Thea Schiebel, Ottmar Möhler, and Frank Stratmann
Atmos. Chem. Phys., 19, 10883–10900,Short summary
For the diverse aerosol on Cyprus, we found the following: new particle formation can be a source of cloud condensation nuclei. Particle hygroscopicity showed that particles ~<100 nm contained mostly organic material, while larger ones were more hygroscopic. Two separate methods obtained similar concentrations of ice-nucleating particles (INP), with mostly no evidence of a local origin. Different parameterizations overestimated INP concentration in this rather polluted region.
Martin Schnaiter, Claudia Linke, Inas Ibrahim, Alexei Kiselev, Fritz Waitz, Thomas Leisner, Stefan Norra, and Till Rehm
Atmos. Chem. Phys., 19, 10829–10844,Short summary
When combustion particles are deposited to the ground, they darken Earth's snow and ice surfaces by even tiny quantities. This darkening reduces the back reflection of sunlight and induces an additional climate warming. Particles from fresh snow samples were investigated according to their light absorption strength. Enhanced absorption was found in the snow that cannot fully be attributed to combustion particles. Dust and biogenic matter are likely the cause of this additional snow darkening.
Huisheng Bian, Karl Froyd, Daniel M. Murphy, Jack Dibb, Anton Darmenov, Mian Chin, Peter R. Colarco, Arlindo da Silva, Tom L. Kucsera, Gregory Schill, Hongbin Yu, Paul Bui, Maximilian Dollner, Bernadett Weinzierl, and Alexander Smirnov
Atmos. Chem. Phys., 19, 10773–10785,Short summary
We address the GEOS-GOCART sea salt simulations constrained by NASA EVS ATom measurements, as well as those by MODIS and the AERONET MAN. The study covers remote regions over the Pacific, Atlantic, and Southern oceans from near the surface to ~ 12 km altitude and covers both summer and winter seasons. Important sea salt fields, e.g., mass mixing ratio, vertical distribution, size distribution, and marine aerosol AOD, as well as their relationship to relative humidity and emissions, are examined.
Carly L. Reddington, William T. Morgan, Eoghan Darbyshire, Joel Brito, Hugh Coe, Paulo Artaxo, Catherine E. Scott, John Marsham, and Dominick V. Spracklen
Atmos. Chem. Phys., 19, 9125–9152,Short summary
We use an aerosol model and observations to explore model representation of aerosol emissions from fires in the Amazon. We find that observed aerosol concentrations are captured by the model over deforestation fires in the western Amazon but underestimated over savanna fires in the Cerrado environment. The model underestimates observed aerosol optical depth (AOD) even when the observed aerosol vertical profile is reproduced. We suggest this may be due to uncertainties in the AOD calculation.
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,Short summary
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.
George S. Fanourgakis, Maria Kanakidou, Athanasios Nenes, Susanne E. Bauer, Tommi Bergman, Ken S. Carslaw, Alf Grini, Douglas S. Hamilton, Jill S. Johnson, Vlassis A. Karydis, Alf Kirkevåg, John K. Kodros, Ulrike Lohmann, Gan Luo, Risto Makkonen, Hitoshi Matsui, David Neubauer, Jeffrey R. Pierce, Julia Schmale, Philip Stier, Kostas Tsigaridis, Twan van Noije, Hailong Wang, Duncan Watson-Parris, Daniel M. Westervelt, Yang Yang, Masaru Yoshioka, Nikos Daskalakis, Stefano Decesari, Martin Gysel-Beer, Nikos Kalivitis, Xiaohong Liu, Natalie M. Mahowald, Stelios Myriokefalitakis, Roland Schrödner, Maria Sfakianaki, Alexandra P. Tsimpidi, Mingxuan Wu, and Fangqun Yu
Atmos. Chem. Phys., 19, 8591–8617,Short summary
Effects of aerosols on clouds are important for climate studies but are among the largest uncertainties in climate projections. This study evaluates the skill of global models to simulate aerosol, cloud condensation nuclei (CCN) and cloud droplet number concentrations (CDNCs). Model results show reduced spread in CDNC compared to CCN due to the negative correlation between the sensitivities of CDNC to aerosol number concentration (air pollution) and updraft velocity (atmospheric dynamics).
Jonathan W. Taylor, Sophie L. Haslett, Keith Bower, Michael Flynn, Ian Crawford, James Dorsey, Tom Choularton, Paul J. Connolly, Valerian Hahn, Christiane Voigt, Daniel Sauer, Régis Dupuy, Joel Brito, Alfons Schwarzenboeck, Thierry Bourriane, Cyrielle Denjean, Phil Rosenberg, Cyrille Flamant, James D. Lee, Adam R. Vaughan, Peter G. Hill, Barbara Brooks, Valéry Catoire, Peter Knippertz, and Hugh Coe
Atmos. Chem. Phys., 19, 8503–8522,Short summary
Low-level clouds cover a wide area of southern West Africa (SWA) and play an important role in the region's climate, reflecting sunlight away from the surface. We performed aircraft measurements of aerosols and clouds over SWA during the 2016 summer monsoon and found pollution, and polluted clouds, across the whole region. Smoke from biomass burning in Central Africa is transported to West Africa, causing a polluted background which limits the effect of local pollution on cloud properties.
Theresa Haller, Christian Rentenberger, Jannik C. Meyer, Laura Felgitsch, Hinrich Grothe, and Regina Hitzenberger
Atmos. Meas. Tech., 12, 3503–3519,Short summary
In thermal–optical measurement techniques – widely used techniques to separate organic and elemental carbon – a filter sample is heated stepwise first in He and then in He+O2. Pyrolysis of organic material occurring during heating in He influences the results but is not fully understood. In this study, structural changes of carbonaceous material during a thermal–optical heating procedure are analyzed with Raman spectroscopy, TEM, UV–VIS and the integrating-sphere method.
Jamie M. Kelly, Ruth M. Doherty, Fiona M. O'Connor, Graham W. Mann, Hugh Coe, and Dantong Liu
Geosci. Model Dev., 12, 2539–2569,Short summary
This study develops the representation of secondary organic aerosol (SOA) within a global chemistry–climate model (UKCA). Both dry and wet deposition within the UKCA model are extended to consider precursors of SOA. The oxidation mechanism describing SOA formation is also extended by adding a reaction intermediate, with SOA yields that are dependent on oxidant concentrations.
Nicholas W. Davies, Cathryn Fox, Kate Szpek, Michael I. Cotterell, Jonathan W. Taylor, James D. Allan, Paul I. Williams, Jamie Trembath, Jim M. Haywood, and Justin M. Langridge
Atmos. Meas. Tech., 12, 3417–3434,Short summary
This research project assesses biases in traditional, filter-based, aerosol absorption measurements by comparison to state-of-the-art, non-filter-based, or in situ, measurements. We assess biases in traditional absorption measurements for three main aerosol types, including dust and fresh and aged biomass burning aerosols. The main results of this study are that the traditional and state-of-the-art absorption measurements are well correlated and that biases in the former are up to 45 %.
Charles A. Brock, Christina Williamson, Agnieszka Kupc, Karl D. Froyd, Frank Erdesz, Nicholas Wagner, Matthews Richardson, Joshua P. Schwarz, Ru-Shan Gao, Joseph M. Katich, Pedro Campuzano-Jost, Benjamin A. Nault, Jason C. Schroder, Jose L. Jimenez, Bernadett Weinzierl, Maximilian Dollner, ThaoPaul Bui, and Daniel M. Murphy
Atmos. Meas. Tech., 12, 3081–3099,Short summary
From 2016 to 2018 a NASA aircraft profiled the atmosphere from 180 m to ~12 km from the Arctic to the Antarctic over both the Pacific and Atlantic oceans. This program, ATom, sought to sample atmospheric chemical composition to compare with global climate models. We describe the how measurements of particulate matter were made during ATom, and show that the instrument performance was excellent. Data from this project can be used with confidence to evaluate models and compare with satellites.
Zongbo Shi, Tuan Vu, Simone Kotthaus, Roy M. Harrison, Sue Grimmond, Siyao Yue, Tong Zhu, James Lee, Yiqun Han, Matthias Demuzere, Rachel E. Dunmore, Lujie Ren, Di Liu, Yuanlin Wang, Oliver Wild, James Allan, W. Joe Acton, Janet Barlow, Benjamin Barratt, David Beddows, William J. Bloss, Giulia Calzolai, David Carruthers, David C. Carslaw, Queenie Chan, Lia Chatzidiakou, Yang Chen, Leigh Crilley, Hugh Coe, Tie Dai, Ruth Doherty, Fengkui Duan, Pingqing Fu, Baozhu Ge, Maofa Ge, Daobo Guan, Jacqueline F. Hamilton, Kebin He, Mathew Heal, Dwayne Heard, C. Nicholas Hewitt, Michael Hollaway, Min Hu, Dongsheng Ji, Xujiang Jiang, Rod Jones, Markus Kalberer, Frank J. Kelly, Louisa Kramer, Ben Langford, Chun Lin, Alastair C. Lewis, Jie Li, Weijun Li, Huan Liu, Junfeng Liu, Miranda Loh, Keding Lu, Franco Lucarelli, Graham Mann, Gordon McFiggans, Mark R. Miller, Graham Mills, Paul Monk, Eiko Nemitz, Fionna O'Connor, Bin Ouyang, Paul I. Palmer, Carl Percival, Olalekan Popoola, Claire Reeves, Andrew R. Rickard, Longyi Shao, Guangyu Shi, Dominick Spracklen, David Stevenson, Yele Sun, Zhiwei Sun, Shu Tao, Shengrui Tong, Qingqing Wang, Wenhua Wang, Xinming Wang, Xuejun Wang, Zifang Wang, Lianfang Wei, Lisa Whalley, Xuefang Wu, Zhijun Wu, Pinhua Xie, Fumo Yang, Qiang Zhang, Yanli Zhang, Yuanhang Zhang, and Mei Zheng
Atmos. Chem. Phys., 19, 7519–7546,Short summary
APHH-Beijing is a collaborative international research programme to study the sources, processes and health effects of air pollution in Beijing. This introduction to the special issue provides an overview of (i) the APHH-Beijing programme, (ii) the measurement and modelling activities performed as part of it and (iii) the air quality and meteorological conditions during joint intensive field campaigns as a core activity within APHH-Beijing.
Dantong Liu, Rutambhara Joshi, Junfeng Wang, Chenjie Yu, James D. Allan, Hugh Coe, Michael J. Flynn, Conghui Xie, James Lee, Freya Squires, Simone Kotthaus, Sue Grimmond, Xinlei Ge, Yele Sun, and Pingqing Fu
Atmos. Chem. Phys., 19, 6749–6769,Short summary
This study provides source attribution and characterization of BC in the Beijing urban environment in both winter and summer. For the first time, the physically and chemically based source apportionments are compared to evaluate the primary source contribution and secondary processing of BC-containing particles. A method is proposed to isolate the BC from the transportation sector and coal combustion sources.
Eoghan Darbyshire, William T. Morgan, James D. Allan, Dantong Liu, Michael J. Flynn, James R. Dorsey, Sebastian J. O'Shea, Douglas Lowe, Kate Szpek, Franco Marenco, Ben T. Johnson, Stephane Bauguitte, Jim M. Haywood, Joel F. Brito, Paulo Artaxo, Karla M. Longo, and Hugh Coe
Atmos. Chem. Phys., 19, 5771–5790,Short summary
A novel analysis of aerosol and gas-phase vertical profiles shows a marked regional pollution contrast: composition is driven by the fire regime and vertical distribution is driven by thermodynamics. These drivers ought to be well represented in simulations to ensure realistic prediction of climate and air quality impacts. The BC : CO ratio in haze and plumes increases with altitude – long-range transport or fire stage coupled to plume dynamics may be responsible. Further enquiry is advocated.
James Brooks, James D. Allan, Paul I. Williams, Dantong Liu, Cathryn Fox, Jim Haywood, Justin M. Langridge, Ellie J. Highwood, Sobhan K. Kompalli, Debbie O'Sullivan, Suresh S. Babu, Sreedharan K. Satheesh, Andrew G. Turner, and Hugh Coe
Atmos. Chem. Phys., 19, 5615–5634,Short summary
Our study, for the first time, presents measurements of aerosol chemical composition and physical characteristics across northern India in the pre-monsoon and monsoon seasons of 2016 using the FAAM BAe-146 UK research aircraft. Across northern India, an elevated aerosol layer dominated by sulfate aerosol exists that diminishes with monsoon arrival. The Indo-Gangetic Plain (IGP) boundary layer is dominated by organics, whereas outside the IGP sulfate dominates with increased scattering aerosol.
Zamin A. Kanji, Ryan C. Sullivan, Monika Niemand, Paul J. DeMott, Anthony J. Prenni, Cédric Chou, Harald Saathoff, and Ottmar Möhler
Atmos. Chem. Phys., 19, 5091–5110,Short summary
The ice nucleation ability of two natural desert dusts coated with a proxy of secondary organic aerosol is presented for temperatures and relative humidity conditions relevant for mixed-phase clouds. We find that at the tested conditions, there is no effect on the ice nucleation ability of the particles due to the organic coating. Furthermore, the two dust samples do not show variability within measurement uncertainty. Particle size and surface area may play a role in any difference observed.
Naruki Hiranuma, Kouji Adachi, David M. Bell, Franco Belosi, Hassan Beydoun, Bhaskar Bhaduri, Heinz Bingemer, Carsten Budke, Hans-Christian Clemen, Franz Conen, Kimberly M. Cory, Joachim Curtius, Paul J. DeMott, Oliver Eppers, Sarah Grawe, Susan Hartmann, Nadine Hoffmann, Kristina Höhler, Evelyn Jantsch, Alexei Kiselev, Thomas Koop, Gourihar Kulkarni, Amelie Mayer, Masataka Murakami, Benjamin J. Murray, Alessia Nicosia, Markus D. Petters, Matteo Piazza, Michael Polen, Naama Reicher, Yinon Rudich, Atsushi Saito, Gianni Santachiara, Thea Schiebel, Gregg P. Schill, Johannes Schneider, Lior Segev, Emiliano Stopelli, Ryan C. Sullivan, Kaitlyn Suski, Miklós Szakáll, Takuya Tajiri, Hans Taylor, Yutaka Tobo, Romy Ullrich, Daniel Weber, Heike Wex, Thomas F. Whale, Craig L. Whiteside, Katsuya Yamashita, Alla Zelenyuk, and Ottmar Möhler
Atmos. Chem. Phys., 19, 4823–4849,Short summary
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.
Xiaoli Shen, Harald Saathoff, Wei Huang, Claudia Mohr, Ramakrishna Ramisetty, and Thomas Leisner
Atmos. Meas. Tech., 12, 2219–2240,Short summary
Based on single-particle mass spectra from field measurements in the upper Rhine valley, we identified characteristic particle classes and estimated their mass contributions without the need of a reference instrument in the field. Our study provides a good example for quantitative interpretation of single-particle data. Together with the complimentary results from bulk measurements, we have shown how a better understanding of the mixing state of ambient aerosol particles can be achieved.
Daniel M. Murphy, Karl D. Froyd, Huisheng Bian, Charles A. Brock, Jack E. Dibb, Joshua P. DiGangi, Glenn Diskin, Maximillian Dollner, Agnieszka Kupc, Eric M. Scheuer, Gregory P. Schill, Bernadett Weinzierl, Christina J. Williamson, and Pengfei Yu
Atmos. Chem. Phys., 19, 4093–4104,Short summary
We present the first data on the concentration of sea-salt aerosol throughout most of the depth of the troposphere and a wide range of latitudes. Sea-salt concentrations in the upper troposphere are very small. This puts stringent limits on how sea-salt aerosol affects halogen and nitric acid chemistry there. With a widely distributed source, sea-salt aerosol provides an excellent test of wet scavenging and vertical transport of aerosols in chemical transport models.
Ghislain Motos, Julia Schmale, Joel C. Corbin, Rob. L. Modini, Nadine Karlen, Michele Bertò, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Chem. Phys., 19, 3833–3855,Short summary
Atmospheric black carbon (BC) particles are strong light absorbers that contribute to global warming. In situ cloud measurements performed at a high-altitude site showed that cloud supersaturation mainly drives the activation of BC to cloud droplets. It was further shown how BC particle size and mixing state modulate this nucleation scavenging in agreement with simplified theoretical predictions. These findings can inform model simulations towards a better representation of the BC life cycle.
Shiwen Teng, Chao Liu, Martin Schnaiter, Rajan K. Chakrabarty, and Fengshan Liu
Atmos. Chem. Phys., 19, 2917–2931,Short summary
Black carbon (BC) possesses complex minor structures besides the overall aggregate geometry, thus altering their optical properties. This study introduces volume variation to quantify and unify different minor structures and develops an empirical relation to account for their effects on BC optical properties. We find the effects of minor structures are mainly contributed by their influence on particle volume/mass, and a relative difference of 5 % is noticed after removing volume differences.
Thomas J. Bannan, Michael Le Breton, Michael Priestley, Stephen D. Worrall, Asan Bacak, Nicholas A. Marsden, Archit Mehra, Julia Hammes, Mattias Hallquist, M. Rami Alfarra, Ulrich K. Krieger, Jonathan P. Reid, John Jayne, Wade Robinson, Gordon McFiggans, Hugh Coe, Carl J. Percival, and Dave Topping
Atmos. Meas. Tech., 12, 1429–1439,Short summary
The Filter Inlet for Gases and AEROsols (FIGAERO) is an inlet designed to be coupled with a high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) and provides simultaneous molecular information relating to both the gas- and particle-phase samples. This method has been used to extract vapour pressures of compounds whilst giving quantitative concentrations in the particle phase. Here we detail an ideal set of benchmark compounds for characterization of the FIGAERO.
Nicholas A. Marsden, Romy Ullrich, Ottmar Möhler, Stine Eriksen Hammer, Konrad Kandler, Zhiqiang Cui, Paul I. Williams, Michael J. Flynn, Dantong Liu, James D. Allan, and Hugh Coe
Atmos. Chem. Phys., 19, 2259–2281,Short summary
The composition of airborne dust influences climate and ecosystems but its measurements presents a huge analytical challenge. Using online single-particle mass spectrometry, we demonstrate differences in mineralogy and mixing state can be detected in real time in both laboratory studies and ambient measurements. The results provide insights into the temporal and spatial evolution of dust properties that will be useful for aerosol–cloud interaction studies and dust cycle modelling.
Ghislain Motos, Julia Schmale, Joel C. Corbin, Marco Zanatta, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Chem. Phys., 19, 2183–2207,Short summary
Clouds form by condensation of water vapour on aerosol particles. We showed that black carbon, a subset of particles responsible for a climate warming due to their strong light absorption and known to be insoluble in water, were able to form droplets when the humidity of the air is very slightly over 100 %. This is made possible by their acquisition of a
coatingmade of hydrophilic material during atmospheric aging. The predictability of this process using theory was successfully tested.
Sophie L. Haslett, Jonathan W. Taylor, Konrad Deetz, Bernhard Vogel, Karmen Babić, Norbert Kalthoff, Andreas Wieser, Cheikh Dione, Fabienne Lohou, Joel Brito, Régis Dupuy, Alfons Schwarzenboeck, Paul Zieger, and Hugh Coe
Atmos. Chem. Phys., 19, 1505–1520,Short summary
As the population in West Africa grows and air pollution increases, it is becoming ever more important to understand the effects of this pollution on the climate and on health. Aerosol particles can grow by absorbing water from the air around them. This paper shows that during the monsoon season, aerosol particles in the region are likely to grow significantly because of the high moisture in the air. This means that climate effects from increasing pollution will be enhanced.
J. Christopher Kaiser, Johannes Hendricks, Mattia Righi, Patrick Jöckel, Holger Tost, Konrad Kandler, Bernadett Weinzierl, Daniel Sauer, Katharina Heimerl, Joshua P. Schwarz, Anne E. Perring, and Thomas Popp
Geosci. Model Dev., 12, 541–579,Short summary
The implementation of the aerosol microphysics submodel MADE3 into the global atmospheric chemistry model EMAC is described and evaluated against an extensive pool of observational data, focusing on aerosol mass and number concentrations, size distributions, composition, and optical properties. EMAC (MADE3) is able to reproduce main aerosol properties reasonably well, in line with the performance of other global aerosol models.
Junfeng Wang, Dantong Liu, Xinlei Ge, Yangzhou Wu, Fuzhen Shen, Mindong Chen, Jian Zhao, Conghui Xie, Qingqing Wang, Weiqi Xu, Jie Zhang, Jianlin Hu, James Allan, Rutambhara Joshi, Pingqing Fu, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 447–458,Short summary
This work is part of the UK-China APHH campaign. We used a laser-only Aerodyne soot particle aerosol mass spectrometer, for the first time, to investigate the concentrations, size distributions and chemical compositions for those ambient submicron aerosol particles only with black carbon as cores. Our findings are valuable to understand the BC properties and processes in the densely populated megacities.
Conghui Xie, Weiqi Xu, Junfeng Wang, Qingqing Wang, Dantong Liu, Guiqian Tang, Ping Chen, Wei Du, Jian Zhao, Yingjie Zhang, Wei Zhou, Tingting Han, Qingyun Bian, Jie Li, Pingqing Fu, Zifa Wang, Xinlei Ge, James Allan, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 19, 165–179,Short summary
We present the first simultaneous real-time online measurements of aerosol optical properties at ground level and at 260 m on a meteorological tower in urban Beijing in winter. The vertical similarities and differences in scattering and absorption coefficients were characterized. The increases in MAC of BC were mainly associated with the coating materials on rBC. Coal combustion was the dominant source contribution of brown carbon followed by biomass burning and SOA in winter in Beijing.
Nivedita K. Kumar, Joel C. Corbin, Emily A. Bruns, Dario Massabó, Jay G. Slowik, Luka Drinovec, Griša Močnik, Paolo Prati, Athanasia Vlachou, Urs Baltensperger, Martin Gysel, Imad El-Haddad, and André S. H. Prévôt
Atmos. Chem. Phys., 18, 17843–17861,Short summary
It is clear that considerable uncertainties still exist in understanding the magnitude of aerosol absorption on a global scale and its contribution to global warming. This manuscript provides a comprehensive assessment of the optical absorption by organic aerosols (brown carbon) from residential wood combustion as a function of atmospheric aging.
Kaitlyn J. Suski, David M. Bell, Naruki Hiranuma, Ottmar Möhler, Dan Imre, and Alla Zelenyuk
Atmos. Chem. Phys., 18, 17497–17513,Short summary
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.
Claire L. Ryder, Franco Marenco, Jennifer K. Brooke, Victor Estelles, Richard Cotton, Paola Formenti, James B. McQuaid, Hannah C. Price, Dantong Liu, Patrick Ausset, Phil D. Rosenberg, Jonathan W. Taylor, Tom Choularton, Keith Bower, Hugh Coe, Martin Gallagher, Jonathan Crosier, Gary Lloyd, Eleanor J. Highwood, and Benjamin J. Murray
Atmos. Chem. Phys., 18, 17225–17257,Short summary
Every year, millions of tons of Saharan dust particles are carried across the Atlantic by the wind, where they can affect weather patterns and climate. Their sizes span orders of magnitude, but the largest (over 10 microns – around the width of a human hair) are difficult to measure and few observations exist. Here we show new aircraft observations of large dust particles, finding more than we would expect, and we quantify their properties which allow them to interact with atmospheric radiation.
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,Short summary
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.
Emma Järvinen, Olivier Jourdan, David Neubauer, Bin Yao, Chao Liu, Meinrat O. Andreae, Ulrike Lohmann, Manfred Wendisch, Greg M. McFarquhar, Thomas Leisner, and Martin Schnaiter
Atmos. Chem. Phys., 18, 15767–15781,Short summary
Using light diffraction it is possible to detect microscopic features within ice particles that have not yet been fully characterized. Here, this technique was applied in airborne measurements, where it was found that majority of atmospheric ice particles have features that significantly change the way ice particles interact with solar light. The microscopic features make ice-containing clouds more reflective than previously thought, which could have consequences for predicting our climate.
Matthias Hummel, Corinna Hoose, Bernhard Pummer, Caroline Schaupp, Janine Fröhlich-Nowoisky, and Ottmar Möhler
Atmos. Chem. Phys., 18, 15437–15450,Short summary
How important for clouds is the ability of biological particles to glaciate droplets at little supercooling? In a case study, the regional atmospheric model COSMO–ART is used. Perturbed and control runs are compared. The number of ice particles that are nucleated by biological particles is highest at around −10 °C. No significant influence on the average state of the cloud ice phase was found. However, the number of ice crystals is slightly enhanced in the absence of other ice nucleators.
Costa D. Christopoulos, Sarvesh Garimella, Maria A. Zawadowicz, Ottmar Möhler, and Daniel J. Cziczo
Atmos. Meas. Tech., 11, 5687–5699,Short summary
Compositional analysis of atmospheric and laboratory aerosols is often conducted with mass spectrometry. In this study, machine learning is used to automatically differentiate particles on the basis of chemistry and size. The ability of the machine learning algorithm was then tested on a data set for which the particles were not initially known to judge its ability.
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,Short summary
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.
Christopher Dearden, Adrian Hill, Hugh Coe, and Tom Choularton
Atmos. Chem. Phys., 18, 14253–14269,Short summary
We perform computer simulations of the life cycle of low-lying clouds over southern West Africa during the monsoon season. Such clouds tend not to produce much precipitation, but they do affect the regional climate by modifying the amount of sunlight reaching the surface. The aim of this work is to understand the factors that influence the growth and break-up of these clouds. We show that the number of water droplets contained within the clouds affects how quickly they dissipate.
Konrad Deetz, Heike Vogel, Sophie Haslett, Peter Knippertz, Hugh Coe, and Bernhard Vogel
Atmos. Chem. Phys., 18, 14271–14295,Short summary
Water uptake can significantly increase the size and therefore alters the optical properties of aerosols. Our model study reveals that the high moisture and aerosol burden in the southern West African monsoon layer makes it favorable to quantify properties that determine the aerosol liquid water content and its impact on the aerosol optical depth and radiative transfer. Especially in moist tropical environments the relative humidity impact on AOD has to be considered in atmospheric models.
Marco Zanatta, Paolo Laj, Martin Gysel, Urs Baltensperger, Stergios Vratolis, Konstantinos Eleftheriadis, Yutaka Kondo, Philippe Dubuisson, Victor Winiarek, Stelios Kazadzis, Peter Tunved, and Hans-Werner Jacobi
Atmos. Chem. Phys., 18, 14037–14057,Short summary
The research community aims to quantify the actual contribution of soot particles to the recent Arctic warming. We discovered that mixing of soot with other components might enhance its light absorption power by 50 %. The neglection of such amplification might lead to the underestimation of radiative forcing by 0.12 W m−2. Thus a better understanding of the optical properties of soot is a crucial step for an accurate quantification of the radiative impact of soot in the Arctic atmosphere.
Michael Priestley, Michael le Breton, Thomas J. Bannan, Stephen D. Worrall, Asan Bacak, Andrew R. D. Smedley, Ernesto Reyes-Villegas, Archit Mehra, James Allan, Ann R. Webb, Dudley E. Shallcross, Hugh Coe, and Carl J. Percival
Atmos. Chem. Phys., 18, 13481–13493,
Wei Zhou, Jian Zhao, Bin Ouyang, Archit Mehra, Weiqi Xu, Yuying Wang, Thomas J. Bannan, Stephen D. Worrall, Michael Priestley, Asan Bacak, Qi Chen, Conghui Xie, Qingqing Wang, Junfeng Wang, Wei Du, Yingjie Zhang, Xinlei Ge, Penglin Ye, James D. Lee, Pingqing Fu, Zifa Wang, Douglas Worsnop, Roderic Jones, Carl J. Percival, Hugh Coe, and Yele Sun
Atmos. Chem. Phys., 18, 11581–11597,Short summary
We present measurements of gas-phase N2O5 and ClNO2 by ToF-CIMS during summer in urban Beijing as part of the APHH campaign. High reactivity of N2O5 indicative of active nocturnal chemistry was observed. The lifetime of N2O5 as a function of aerosol surface area and relative humidity was characterized, and N2O5 uptake coefficients were estimated. We also found that the N2O5 loss in this study is mainly attributed to its indirect loss via reactions of NO3 with VOCs and NO.
Kelly L. Pereira, Rachel Dunmore, James Whitehead, M. Rami Alfarra, James D. Allan, Mohammed S. Alam, Roy M. Harrison, Gordon McFiggans, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 18, 11073–11096,Short summary
Exhaust emissions from a light-duty diesel engine were introduced into an atmospheric simulation chamber which was used as a holding-cell for sampling, allowing instruments capable of providing detailed chemical speciation of exhaust gas emissions to be used. The effect of different engine conditions on the exhaust gas composition was investigated. The exhaust composition changed considerably due to two influencing factors, engine combustion and diesel oxidative catalyst efficiency.
Ramakrishna Ramisetty, Ahmed Abdelmonem, Xiaoli Shen, Harald Saathoff, Thomas Leisner, and Claudia Mohr
Atmos. Meas. Tech., 11, 4345–4360,Short summary
In this study we coupled a laser ablation aerosol time-of-flight (LAAPTOF) single-particle mass spectrometer, originally equipped with an excimer laser, to a femtosecond laser. The objective was to assess the influence of the higher laser power density of the femtosecond laser on ablation–ionization of atmospheric particles, ion signal, and ultimately quantitative abilities of the single-particle mass spectrometer.
Konrad Deetz, Heike Vogel, Peter Knippertz, Bianca Adler, Jonathan Taylor, Hugh Coe, Keith Bower, Sophie Haslett, Michael Flynn, James Dorsey, Ian Crawford, Christoph Kottmeier, and Bernhard Vogel
Atmos. Chem. Phys., 18, 9767–9788,Short summary
Highly resolved process study simulations for 2–3 July are conducted with COSMO-ART to assess the aerosol direct and indirect effect on meteorological conditions over southern West Africa. The meteorological phenomena of Atlantic inflow and stratus-to-cumulus transition are identified as highly susceptible to the aerosol direct effect, leading to a spatial shift of the Atlantic inflow front and a temporal shift of the stratus-to-cumulus transition with changes in the aerosol amount.
Marco Pandolfi, Lucas Alados-Arboledas, Andrés Alastuey, Marcos Andrade, Christo Angelov, Begoña Artiñano, John Backman, Urs Baltensperger, Paolo Bonasoni, Nicolas Bukowiecki, Martine Collaud Coen, Sébastien Conil, Esther Coz, Vincent Crenn, Vadimas Dudoitis, Marina Ealo, Kostas Eleftheriadis, Olivier Favez, Prodromos Fetfatzis, Markus Fiebig, Harald Flentje, Patrick Ginot, Martin Gysel, Bas Henzing, Andras Hoffer, Adela Holubova Smejkalova, Ivo Kalapov, Nikos Kalivitis, Giorgos Kouvarakis, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Chris Lunder, Krista Luoma, Hassan Lyamani, Angela Marinoni, Nikos Mihalopoulos, Marcel Moerman, José Nicolas, Colin O'Dowd, Tuukka Petäjä, Jean-Eudes Petit, Jean Marc Pichon, Nina Prokopciuk, Jean-Philippe Putaud, Sergio Rodríguez, Jean Sciare, Karine Sellegri, Erik Swietlicki, Gloria Titos, Thomas Tuch, Peter Tunved, Vidmantas Ulevicius, Aditya Vaishya, Milan Vana, Aki Virkkula, Stergios Vratolis, Ernest Weingartner, Alfred Wiedensohler, and Paolo Laj
Atmos. Chem. Phys., 18, 7877–7911,Short summary
This investigation presents the variability in near-surface in situ aerosol particle light-scattering measurements obtained over the past decade at 28 measuring atmospheric observatories which are part of the ACTRIS Research Infrastructure, and most of them belong to the GAW network. This paper provides a comprehensive picture of the spatial and temporal variability of aerosol particles optical properties in Europe.
Sekou Keita, Cathy Liousse, Véronique Yoboué, Pamela Dominutti, Benjamin Guinot, Eric-Michel Assamoi, Agnès Borbon, Sophie L. Haslett, Laetitia Bouvier, Aurélie Colomb, Hugh Coe, Aristide Akpo, Jacques Adon, Julien Bahino, Madina Doumbia, Julien Djossou, Corinne Galy-Lacaux, Eric Gardrat, Sylvain Gnamien, Jean F. Léon, Money Ossohou, E. Touré N'Datchoh, and Laurent Roblou
Atmos. Chem. Phys., 18, 7691–7708,Short summary
This study provides emission factor (EF) data for elemental and organic carbon, total particulate matter and 58 volatile organic compound species for combustion sources specific to Africa to establish emission inventories with less uncertainty. EFs obtained in this study are generally higher than those in the literature whose values are used in emissions inventories for Africa. This shows that particles and VOC emissions were sometimes underestimated and underlines this study's importance.
Chao Liu, Chul Eddy Chung, Yan Yin, and Martin Schnaiter
Atmos. Chem. Phys., 18, 6259–6273,Short summary
The absorption Ångström exponent (AAE) of black carbon (BC) is widely accepted to be 1.0, although observational estimates give a quite wide range of 0.6–1.1. This study investigates BC AAE numerically using realistic particle properties and accurate numerical models. The significantly influence of BC microphysical properties on BC AAE is revealed by simple linear formulas, and the widely accepted BC AAE value of 1.0 is not correct for even small BC with wavelength-independent refractive index.
Amy K. Hodgson, William T. Morgan, Sebastian O'Shea, Stéphane Bauguitte, James D. Allan, Eoghan Darbyshire, Michael J. Flynn, Dantong Liu, James Lee, Ben Johnson, Jim M. Haywood, Karla M. Longo, Paulo E. Artaxo, and Hugh Coe
Atmos. Chem. Phys., 18, 5619–5638,Short summary
We flew a large atmospheric research aircraft across a number of different biomass burning environments in the Amazon Basin in September and October 2012. In this paper, we focus on smoke sampled very close to fresh fires (only 600–900 m above the fires and smoke that was 4–6 min old) to examine the chemical components that make up the smoke and their abundance. We found substantial differences in the emitted smoke that are due to the fuel type and combustion processes driving the fires.
Xiaoli Shen, Ramakrishna Ramisetty, Claudia Mohr, Wei Huang, Thomas Leisner, and Harald Saathoff
Atmos. Meas. Tech., 11, 2325–2343,Short summary
This paper presents performance data and reference spectra from the commercially available single-particle mass spectrometer LAAPTOF. The main characteristics of the instrument, like its detection efficiency, are given for a wide particle size range. Furthermore, reference mass spectra for 32 well-defined different particle types relevant for atmospheric aerosol compounds are presented. It is shown that these reference mass spectra are very useful in analysis of atmospheric aerosol particles.
Riinu Ots, Mathew R. Heal, Dominique E. Young, Leah R. Williams, James D. Allan, Eiko Nemitz, Chiara Di Marco, Anais Detournay, Lu Xu, Nga L. Ng, Hugh Coe, Scott C. Herndon, Ian A. Mackenzie, David C. Green, Jeroen J. P. Kuenen, Stefan Reis, and Massimo Vieno
Atmos. Chem. Phys., 18, 4497–4518,Short summary
The main hypothesis of this paper is that people who live in large cities in the UK disobey the
smoke control lawas it has not been actively enforced for decades now. However, the use of wood in residential heating has increased, partly due to renewable energy targets, but also for discretionary (i.e. pleasant fireplaces) reasons. Our study is based mainly in London, but similar struggles with urban air quality due to residential wood and coal burning are seen in other major European cities.
James D. Lee, Stephen D. Mobbs, Axel Wellpott, Grant Allen, Stephane J.-B. Bauguitte, Ralph R. Burton, Richard Camilli, Hugh Coe, Rebecca E. Fisher, James L. France, Martin Gallagher, James R. Hopkins, Mathias Lanoiselle, Alastair C. Lewis, David Lowry, Euan G. Nisbet, Ruth M. Purvis, Sebastian O'Shea, John A. Pyle, and Thomas B. Ryerson
Atmos. Meas. Tech., 11, 1725–1739,Short summary
This work describes measurements, made from an aircraft platform, of the emission of methane and other organic gases from an uncontrolled leak from an oil platform in the North Sea (Total Elgin). The measurements made helped the platform operators to devise a strategy for repairing the leak and serve as a methodology for assessing future similar incidents.
Ernesto Reyes-Villegas, Michael Priestley, Yu-Chieh Ting, Sophie Haslett, Thomas Bannan, Michael Le Breton, Paul I. Williams, Asan Bacak, Michael J. Flynn, Hugh Coe, Carl Percival, and James D. Allan
Atmos. Chem. Phys., 18, 4093–4111,Short summary
This work presents the analysis of a special event with high biomass burning emissions, named Bonfire Night. Nitrogen chemistry was observed and it was possible to study the night time chemistry. It was possible to quantify particulate organic oxides of nitrogen (PON) concentrations of 2.8 µg m−3 using 46 : 30 ratios from aerosol mass spectrometry measurements. The use of the receptor model positive matrix factorization (PMF) allowed to separate organic aerosols into different sources.
Dantong Liu, Jonathan W. Taylor, Jonathan Crosier, Nicholas Marsden, Keith N. Bower, Gary Lloyd, Claire L. Ryder, Jennifer K. Brooke, Richard Cotton, Franco Marenco, Alan Blyth, Zhiqiang Cui, Victor Estelles, Martin Gallagher, Hugh Coe, and Tom W. Choularton
Atmos. Chem. Phys., 18, 3817–3838,Short summary
This article presents measurements of aerosol properties off the coast of west Africa during August 2015. For the first time, an airborne laser-induced incandescence instrument was deployed to measure the hematite content of dust. The single scattering albedo of dust was found to be influenced by the hematite content, but depended on the dust source and potential dust age. This highlights the importance of size-dependent composition in determining the optical properties of dust.
Julia Schmale, Silvia Henning, Stefano Decesari, Bas Henzing, Helmi Keskinen, Karine Sellegri, Jurgita Ovadnevaite, Mira L. Pöhlker, Joel Brito, Aikaterini Bougiatioti, Adam Kristensson, Nikos Kalivitis, Iasonas Stavroulas, Samara Carbone, Anne Jefferson, Minsu Park, Patrick Schlag, Yoko Iwamoto, Pasi Aalto, Mikko Äijälä, Nicolas Bukowiecki, Mikael Ehn, Göran Frank, Roman Fröhlich, Arnoud Frumau, Erik Herrmann, Hartmut Herrmann, Rupert Holzinger, Gerard Kos, Markku Kulmala, Nikolaos Mihalopoulos, Athanasios Nenes, Colin O'Dowd, Tuukka Petäjä, David Picard, Christopher Pöhlker, Ulrich Pöschl, Laurent Poulain, André Stephan Henry Prévôt, Erik Swietlicki, Meinrat O. Andreae, Paulo Artaxo, Alfred Wiedensohler, John Ogren, Atsushi Matsuki, Seong Soo Yum, Frank Stratmann, Urs Baltensperger, and Martin Gysel
Atmos. Chem. Phys., 18, 2853–2881,Short summary
Collocated long-term observations of cloud condensation nuclei (CCN) number concentrations, particle number size distributions and chemical composition from 12 sites are synthesized. Observations cover coastal environments, the Arctic, the Mediterranean, the boreal and rain forest, high alpine and continental background sites, and Monsoon-influenced areas. We interpret regional and seasonal variability. CCN concentrations are predicted with the κ–Köhler model and compared to the measurements.
Wei Huang, Harald Saathoff, Aki Pajunoja, Xiaoli Shen, Karl-Heinz Naumann, Robert Wagner, Annele Virtanen, Thomas Leisner, and Claudia Mohr
Atmos. Chem. Phys., 18, 2883–2898,
Katherine M. Manfred, Rebecca A. Washenfelder, Nicholas L. Wagner, Gabriela Adler, Frank Erdesz, Caroline C. Womack, Kara D. Lamb, Joshua P. Schwarz, Alessandro Franchin, Vanessa Selimovic, Robert J. Yokelson, and Daniel M. Murphy
Atmos. Chem. Phys., 18, 1879–1894,Short summary
In this study, we use a new laser imaging nephelometer to measure the bulk aerosol scattering phase function for biomass burning aerosol from controlled fires. By comparing measurements to models for spherical and fractal particles, we demonstrate that the dominant morphology varies by fuel type. This instrument has unique capabilities to directly measure how morphology affects optical properties, and can be used in the future for important validations of remote sensing retrievals.
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,Short summary
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,Short summary
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.
Xuan Wang, Colette L. Heald, Jiumeng Liu, Rodney J. Weber, Pedro Campuzano-Jost, Jose L. Jimenez, Joshua P. Schwarz, and Anne E. Perring
Atmos. Chem. Phys., 18, 635–653,Short summary
Brown carbon (BrC) contributes significantly to uncertainty in estimating the global direct radiative effect (DRE) of aerosols. We develop a global model simulation of BrC and test it against BrC absorption measurements from two aircraft campaigns in the continental United States. We suggest that BrC DRE has been overestimated previously due to the lack of observational constraints from direct measurements and omission of the effects of photochemical whitening.
Martin Schnaiter, Emma Järvinen, Ahmed Abdelmonem, and Thomas Leisner
Atmos. Meas. Tech., 11, 341–357,Short summary
PHIPS-HALO is a novel aircraft instrument for cloud research. It combines microscopic imaging of single cloud particles with the measurement of their spacial light scattering properties. The knowledge of how atmospheric ice particles in clouds scatter visible light is important for improving future climate models.
Sophie L. Haslett, J. Chris Thomas, William T. Morgan, Rory Hadden, Dantong Liu, James D. Allan, Paul I. Williams, Sekou Keita, Cathy Liousse, and Hugh Coe
Atmos. Chem. Phys., 18, 385–403,Short summary
Wood burning is chaotic, so the particles emitted can be difficult to study in a repeatable way. Here, we addressed this problem by carefully controlling small wood fires in the lab. We saw three burning phases, which could be told apart chemically; we also saw evidence of these in measurements of wood burning in London in 2012. Controlled experiments like this help us to understand why emissions are so variable and to recognise burning conditions just from the particles seen in the atmosphere.
Nicholas A. Marsden, Michael J. Flynn, James D. Allan, and Hugh Coe
Atmos. Meas. Tech., 11, 195–213,Short summary
Mineralogy of silicate mineral dust has a strong influence on climate and ecosystems due to variation in physiochemical properties that result from differences in composition and crystal structure (mineral phase). Traditional offline methods of analysing mineral phase are labour intensive and the temporal resolution of the data is lost. We introduce a novel technique that enables the online differentiation of mineral phase in silicate particles by single-particle mass spectrometry.
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,Short summary
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.
Adrian Walser, Daniel Sauer, Antonio Spanu, Josef Gasteiger, and Bernadett Weinzierl
Atmos. Meas. Tech., 10, 4341–4361,Short summary
We present a new approach to model the response of optical particle counters (OPCs) including a simple parametrization for artificial broadening of size spectra induced by the non-ideal behavior of real OPCs. We show a self-consistent way to evaluate calibration measurements and outline how particle number size distributions with realistic uncertainty estimates can be derived. The innovations will improve the accuracy of OPC-derived size distributions and allow to assess their precision.
Jean-Christophe Raut, Louis Marelle, Jerome D. Fast, Jennie L. Thomas, Bernadett Weinzierl, Katharine S. Law, Larry K. Berg, Anke Roiger, Richard C. Easter, Katharina Heimerl, Tatsuo Onishi, Julien Delanoë, and Hans Schlager
Atmos. Chem. Phys., 17, 10969–10995,Short summary
We study the cross-polar transport of plumes from Siberian fires to the Arctic in summer, both in terms of transport pathways and efficiency of deposition processes. Those plumes containing soot may originate from anthropogenic and biomass burning sources in mid-latitude regions and may impact the Arctic climate by depositing on snow and ice surfaces. We evaluate the role of the respective source contributions, investigate the transport of plumes and treat pathway-dependent removal of particles.
Leonid Nichman, Emma Järvinen, James Dorsey, Paul Connolly, Jonathan Duplissy, Claudia Fuchs, Karoliina Ignatius, Kamalika Sengupta, Frank Stratmann, Ottmar Möhler, Martin Schnaiter, and Martin Gallagher
Atmos. Meas. Tech., 10, 3231–3248,Short summary
Optical probes are frequently used for the detection of cloud particles. The detected microphysical properties may affect particle growth and accretion mechanisms and the light scattering properties of cirrus clouds. In the CLOUD chamber study at CERN, we compared four optical measurement techniques. We show that shape derivation alone is not sufficient to determine the phase of the small cloud particles. None of the instruments were able to unambiguously determine the phase of small particles.
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,Short summary
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.
David O. Topping, James Allan, M. Rami Alfarra, and Bernard Aumont
Geosci. Model Dev., 10, 2365–2377,Short summary
Our ability to model the chemical and thermodynamic processes that lead to secondary organic aerosol (SOA) formation is thought to be hampered by the complexity of the system. In this proof of concept study, the ability to train supervised methods to predict electron impact ionisation (EI) mass spectra for the AMS is evaluated to facilitate improved model evaluation. The study demonstrates the use of a methodology that would be improved with more training data and data from simple mixed systems.
Giancarlo Ciarelli, Imad El Haddad, Emily Bruns, Sebnem Aksoyoglu, Ottmar Möhler, Urs Baltensperger, and André S. H. Prévôt
Geosci. Model Dev., 10, 2303–2320,Short summary
In Europe, residential wood-burning emissions constitute one of the main anthropogenic sources of air pollution. Novel wood-burning experiments performed in a state-of-the-art smog chamber provide valuable information on the chemical properties of wood-burning emissions and the transformation in the atmosphere. In this study, these new data were used in a box model to constrain a parameterization suitable for predicting the contribution of wood burning to air pollution with large-scale models.
Ellis Shipley Robinson, Ru-Shan Gao, Joshua P. Schwarz, David W. Fahey, and Anne E. Perring
Atmos. Meas. Tech., 10, 1755–1768,
Jianzhong Sun, Guorui Zhi, Regina Hitzenberger, Yingjun Chen, Chongguo Tian, Yayun Zhang, Yanli Feng, Miaomiao Cheng, Yuzhe Zhang, Jing Cai, Feng Chen, Yiqin Qiu, Zhiming Jiang, Jun Li, Gan Zhang, and Yangzhi Mo
Atmos. Chem. Phys., 17, 4769–4780,Short summary
This paper investigates the emission factors and the light absorption properties of brown carbon (BrC) from China’s household coal burning. Seven coals of various ranks were burned in four typical stoves as both chunk and briquette styles. The optical integrating sphere (IS) method was employed to quantify BrC and black carbon (BC). We conclude that, in the scenario of current household coal burning in China, solar light absorption by BrC accounts for 26.5 % of the total absorption.
Peter Zotter, Hanna Herich, Martin Gysel, Imad El-Haddad, Yanlin Zhang, Griša Močnik, Christoph Hüglin, Urs Baltensperger, Sönke Szidat, and André S. H. Prévôt
Atmos. Chem. Phys., 17, 4229–4249,Short summary
Most studies use a single Ångström exponent for wood burning (αWB) and traffic (αTR) emissions in the Aethalometer model, used for source apportionment of black carbon, derived from previous work. However, accurate determination of the α values is currently lacking. Comparing radiocarbon measurements (14C) with the Aehtalometer model, good agreement was found, indicating that the Aethalometer model reproduces reasonably well the 14C results using our best estimate of a single αWB and αTR.
Ulrike Dusek, Regina Hitzenberger, Anne Kasper-Giebl, Magdalena Kistler, Harro A. J. Meijer, Sönke Szidat, Lukas Wacker, Rupert Holzinger, and Thomas Röckmann
Atmos. Chem. Phys., 17, 3233–3251,Short summary
Measurements of the radioactive carbon isotope 14C allow to identify the sources of aerosol carbon. We report an extensive 14C source apportionment record in the Netherlands with samples covering a whole year. We discovered that long-range transport has a large influence on aerosol carbon levels. Fossil fuel carbon is least influenced by long-range transport and more regional in origin. Biomass burning seems to be a minor source of aerosol carbon in the Netherlands.
Thomas Häusler, Lorenz Witek, Laura Felgitsch, Regina Hitzenberger, and Hinrich Grothe
Atmos. Chem. Phys. Discuss.,
Preprint retractedShort summary
Clouds play a major role for the Earth's climate system. On this account, it is important to fully understand the mechanisms taking place in a cloud. We are presenting a new approach to efficiently investigate the freezing processes in ice clouds, i.e. the behavior of ice nuclei. The new set-up exhibits its strength in reproducibility and accuracy. Finally, it opens a temperature window down to −37 °C for freezing experiments which was not accessible with many former approaches.
Alexandra Tsekeri, Vassilis Amiridis, Franco Marenco, Athanasios Nenes, Eleni Marinou, Stavros Solomos, Phil Rosenberg, Jamie Trembath, Graeme J. Nott, James Allan, Michael Le Breton, Asan Bacak, Hugh Coe, Carl Percival, and Nikolaos Mihalopoulos
Atmos. Meas. Tech., 10, 83–107,Short summary
The In situ/Remote sensing aerosol Retrieval Algorithm (IRRA) provides vertical profiles of aerosol optical, microphysical and hygroscopic properties from airborne in situ and remote sensing measurements. The algorithm is highly advantageous for aerosol characterization in humid conditions, employing the ISORROPIA II model for acquiring the particle hygroscopic growth. IRRA can find valuable applications in aerosol–cloud interaction schemes and in validation of active space-borne sensors.
Josef Gasteiger, Silke Groß, Daniel Sauer, Moritz Haarig, Albert Ansmann, and Bernadett Weinzierl
Atmos. Chem. Phys., 17, 297–311,Short summary
To study aerosol transport in the Saharan Air Layer (SAL) from Africa to the Caribbean, we combine advanced optical models of Saharan aerosols with Stokes settling and two hypotheses about the occurrence of vertical mixing. By testing our hypotheses with lidar and in situ profiles measured near the top of the transported SAL, we find strong evidence that vertical mixing occurs in the SAL over the Atlantic with significant consequences for size distribution of the transported Saharan aerosols.
Ernesto Reyes-Villegas, David C. Green, Max Priestman, Francesco Canonaco, Hugh Coe, André S. H. Prévôt, and James D. Allan
Atmos. Chem. Phys., 16, 15545–15559,Short summary
For the first time in the UK, an Aerosol Chemical Speciation Monitor was used to measure aerosol concentrations in London in March–December 2013, with further organic aerosol (OA) source apportionment using the ME-2 factorization tool. Five OA sources were identified: biomass burning OA, hydrocarbon-like OA, cooking OA, semivolatile oxygenated OA and low-volatility oxygenated OA. This information can be used to take future action on the respective legislation in order to improve the air quality.
Nicholas Marsden, Michael J. Flynn, Jonathan W. Taylor, James D. Allan, and Hugh Coe
Atmos. Meas. Tech., 9, 6051–6068,
Ben T. Johnson, James M. Haywood, Justin M. Langridge, Eoghan Darbyshire, William T. Morgan, Kate Szpek, Jennifer K. Brooke, Franco Marenco, Hugh Coe, Paulo Artaxo, Karla M. Longo, Jane P. Mulcahy, Graham W. Mann, Mohit Dalvi, and Nicolas Bellouin
Atmos. Chem. Phys., 16, 14657–14685,Short summary
Biomass burning is a large source of carbonaceous aerosols, which scatter and absorb solar radiation, and modify cloud properties. We evaluate the simulation of biomass burning aerosol processes and properties in the HadGEM3 climate model using observations, including those from the South American Biomass Burning Analysis. We find that modelled aerosol optical depths are underestimated unless aerosol emissions (Global Fire Emission Database v3) are increased by a factor of 1.6–2.0.
Gillian Young, Hazel M. Jones, Thomas W. Choularton, Jonathan Crosier, Keith N. Bower, Martin W. Gallagher, Rhiannon S. Davies, Ian A. Renfrew, Andrew D. Elvidge, Eoghan Darbyshire, Franco Marenco, Philip R. A. Brown, Hugo M. A. Ricketts, Paul J. Connolly, Gary Lloyd, Paul I. Williams, James D. Allan, Jonathan W. Taylor, Dantong Liu, and Michael J. Flynn
Atmos. Chem. Phys., 16, 13945–13967,Short summary
Clouds are intricately coupled to the Arctic sea ice. Our inability to accurately model cloud fractions causes large uncertainties in predicted radiative interactions in this region, therefore, affecting sea ice forecasts. Here, we present measurements of cloud microphysics, aerosol properties, and thermodynamic structure over the transition from sea ice to ocean to improve our understanding of the relationship between the Arctic atmosphere and clouds which develop in this region.
Claudia Linke, Inas Ibrahim, Nina Schleicher, Regina Hitzenberger, Meinrat O. Andreae, Thomas Leisner, and Martin Schnaiter
Atmos. Meas. Tech., 9, 5331–5346,Short summary
Various carbonaceous materials are present in the atmosphere. Besides gaseous organic compounds, carbonaceous particles like soot are emitted into the air from traffic sources, residential wood combustion, or wildfires. Variable chemical compositions of such materials, which often result from incomplete combustion processes, show differences in the absorption behavior at visible wavelengths. Our instrument is able to measure the absorption at three visible wavelengths.
Riinu Ots, Massimo Vieno, James D. Allan, Stefan Reis, Eiko Nemitz, Dominique E. Young, Hugh Coe, Chiara Di Marco, Anais Detournay, Ian A. Mackenzie, David C. Green, and Mathew R. Heal
Atmos. Chem. Phys., 16, 13773–13789,Short summary
Emissions of cooking organic aerosol (COA; from charbroiling, frying, etc.) are currently absent in European emissions inventories yet measurements have pointed to significant COA concentrations. In this study, emissions of COA were developed for the UK by model iteration against year-long measurements at two sites in London. Modelled COA dropped rapidly outside of major urban areas, suggesting that although a notable component in UK urban air, COA does not have a significant effect on rural PM.
Valery Shcherbakov, Olivier Jourdan, Christiane Voigt, Jean-Francois Gayet, Aurélien Chauvigne, Alfons Schwarzenboeck, Andreas Minikin, Marcus Klingebiel, Ralf Weigel, Stephan Borrmann, Tina Jurkat, Stefan Kaufmann, Romy Schlage, Christophe Gourbeyre, Guy Febvre, Tatyana Lapyonok, Wiebke Frey, Sergej Molleker, and Bernadett Weinzierl
Atmos. Chem. Phys., 16, 11883–11897,
Jonathan W. Taylor, Thomas W. Choularton, Alan M. Blyth, Michael J. Flynn, Paul I. Williams, Gillian Young, Keith N. Bower, Jonathan Crosier, Martin W. Gallagher, James R. Dorsey, Zixia Liu, and Philip D. Rosenberg
Atmos. Chem. Phys., 16, 11687–11709,Short summary
We present measurements of boundary layer aerosol concentration, size and composition from research flights performed over the southwest peninsula of the UK during the COnvective Precipitation Experiment (COPE) of summer 2013. We compare case studies of aerosol in cleaner marine air from the Atlantic with anthropogenic pollution from the UK. These measurements are then used to investigate the possible sources of CCN and IN in the region.
Fernando Chouza, Oliver Reitebuch, Angela Benedetti, and Bernadett Weinzierl
Atmos. Chem. Phys., 16, 11581–11600,
Naruki Hiranuma, Ottmar Möhler, Gourihar Kulkarni, Martin Schnaiter, Steffen Vogt, Paul Vochezer, Emma Järvinen, Robert Wagner, David M. Bell, Jacqueline Wilson, Alla Zelenyuk, and Daniel J. Cziczo
Atmos. Meas. Tech., 9, 3817–3836,Short summary
A new pumped counterflow virtual impactor (PCVI) called the ice-selecting PCVI (IS-PCVI) has been developed to collect ice crystal residuals for investigating physico-chemical properties of ice-nucleating particles. The results show that the ice crystals of volume-equivalent diameter ~ 10 to 30 µm can be efficiently separated from the supercooled droplets and interstitial particles. The IS-PCVI is efficient when the counterflow-to-input flow ratio is within 0.09 to 0.18.
James D. Whitehead, Eoghan Darbyshire, Joel Brito, Henrique M. J. Barbosa, Ian Crawford, Rafael Stern, Martin W. Gallagher, Paul H. Kaye, James D. Allan, Hugh Coe, Paulo Artaxo, and Gordon McFiggans
Atmos. Chem. Phys., 16, 9727–9743,Short summary
We present measurements of aerosols during the transition from wet to dry seasons at a pristine rainforest site in central Amazonia. By excluding pollution episodes, we focus on natural biogenic aerosols. Submicron aerosols are dominated by organic material, similar to previous wet season measurements. Larger particles are dominated by biological material, mostly fungal spores, with higher concentrations at night. This study provides important data on the nature of particles above the Amazon.
Yvonne Boose, Berko Sierau, M. Isabel García, Sergio Rodríguez, Andrés Alastuey, Claudia Linke, Martin Schnaiter, Piotr Kupiszewski, Zamin A. Kanji, and Ulrike Lohmann
Atmos. Chem. Phys., 16, 9067–9087,Short summary
Mineral dust is known to be among the most prevalent ice-nucleating particles (INPs) in the atmosphere, playing a crucial role for ice cloud formation. We present 2 months of ground-based in situ measurements of INP concentrations in the free troposphere close to the largest global dust source, the Sahara. We find that some atmospheric processes such as mixing with biological particles and ammonium increase the dust INP ability. This is important when predicting INPs based on emissions.
Ahmed Abdelmonem, Emma Järvinen, Denis Duft, Edwin Hirst, Steffen Vogt, Thomas Leisner, and Martin Schnaiter
Atmos. Meas. Tech., 9, 3131–3144,Short summary
The properties of ice crystals present in mixed-phase and ice clouds influence the radiation properties, precipitation occurrence and lifetime of these clouds. It is necessary to investigate the optical and microphysical properties of cloud particles particularly in situ, and to get correlation between these properties. To this end we have developed PHIPS-HALO to measure the optical properties and the corresponding microphysical parameters of individual cloud particles simultaneously.
Carsten Warneke, Michael Trainer, Joost A. de Gouw, David D. Parrish, David W. Fahey, A. R. Ravishankara, Ann M. Middlebrook, Charles A. Brock, James M. Roberts, Steven S. Brown, Jonathan A. Neuman, Brian M. Lerner, Daniel Lack, Daniel Law, Gerhard Hübler, Iliana Pollack, Steven Sjostedt, Thomas B. Ryerson, Jessica B. Gilman, Jin Liao, John Holloway, Jeff Peischl, John B. Nowak, Kenneth C. Aikin, Kyung-Eun Min, Rebecca A. Washenfelder, Martin G. Graus, Mathew Richardson, Milos Z. Markovic, Nick L. Wagner, André Welti, Patrick R. Veres, Peter Edwards, Joshua P. Schwarz, Timothy Gordon, William P. Dube, Stuart A. McKeen, Jerome Brioude, Ravan Ahmadov, Aikaterini Bougiatioti, Jack J. Lin, Athanasios Nenes, Glenn M. Wolfe, Thomas F. Hanisco, Ben H. Lee, Felipe D. Lopez-Hilfiker, Joel A. Thornton, Frank N. Keutsch, Jennifer Kaiser, Jingqiu Mao, and Courtney D. Hatch
Atmos. Meas. Tech., 9, 3063–3093,Short summary
In this paper we describe the experimental approach, the science goals and early results of the NOAA SENEX campaign, which was focused on studying the interactions between biogenic and anthropogenic emissions to form secondary pollutants. During SENEX, the NOAA WP-3D aircraft conducted 20 research flights between 27 May and 10 July 2013 based out of Smyrna, TN. The SENEX flights included day- and nighttime flights in the Southeast as well as flights over areas with intense shale gas extraction.
Bernadette Rosati, Martin Gysel, Florian Rubach, Thomas F. Mentel, Brigitta Goger, Laurent Poulain, Patrick Schlag, Pasi Miettinen, Aki Pajunoja, Annele Virtanen, Henk Klein Baltink, J. S. Bas Henzing, Johannes Größ, Gian Paolo Gobbi, Alfred Wiedensohler, Astrid Kiendler-Scharr, Stefano Decesari, Maria Cristina Facchini, Ernest Weingartner, and Urs Baltensperger
Atmos. Chem. Phys., 16, 7295–7315,Short summary
This study presents PEGASOS project data from field campaigns in the Po Valley, Italy and the Netherlands. Vertical profiles of aerosol hygroscopicity and chemical composition were investigated with airborne measurements on board a Zeppelin NT airship. A special focus was on the evolution of different mixing layers within the PBL as a function of daytime. A closure study showed that variations in aerosol hygroscopicity can well be explained by the variations in chemical composition.
Karoliina Ignatius, Thomas B. Kristensen, Emma Järvinen, Leonid Nichman, Claudia Fuchs, Hamish Gordon, Paul Herenz, Christopher R. Hoyle, Jonathan Duplissy, Sarvesh Garimella, Antonio Dias, Carla Frege, Niko Höppel, Jasmin Tröstl, Robert Wagner, Chao Yan, Antonio Amorim, Urs Baltensperger, Joachim Curtius, Neil M. Donahue, Martin W. Gallagher, Jasper Kirkby, Markku Kulmala, Ottmar Möhler, Harald Saathoff, Martin Schnaiter, Antonio Tomé, Annele Virtanen, Douglas Worsnop, and Frank Stratmann
Atmos. Chem. Phys., 16, 6495–6509,Short summary
Viscous solid or semi-solid secondary organic aerosol (SOA) may influence cloud properties through ice nucleation in the atmosphere. Here, we observed heterogeneous ice nucleation of viscous α-pinene SOA at temperatures between −39 °C and −37.2 °C with ice saturation ratios significantly below the homogeneous freezing limit. Global modelling suggests that viscous biogenic SOA are present in regions where cirrus formation takes place and could contribute to the global ice nuclei budget.
Riinu Ots, Dominique E. Young, Massimo Vieno, Lu Xu, Rachel E. Dunmore, James D. Allan, Hugh Coe, Leah R. Williams, Scott C. Herndon, Nga L. Ng, Jacqueline F. Hamilton, Robert Bergström, Chiara Di Marco, Eiko Nemitz, Ian A. Mackenzie, Jeroen J. P. Kuenen, David C. Green, Stefan Reis, and Mathew R. Heal
Atmos. Chem. Phys., 16, 6453–6473,Short summary
This study investigates the contribution of diesel vehicle emissions to organic aerosol formation and particulate matter concentrations in London. Comparisons of simulated pollutant concentrations with observations show good agreement and give confidence in the skill of the model applied. The contribution of diesel vehicle emissions, which are currently not included in official emissions inventories, is demonstrated to be substantial, indicating that more research on this topic is required.
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,
Charles A. Brock, Nicholas L. Wagner, Bruce E. Anderson, Alexis R. Attwood, Andreas Beyersdorf, Pedro Campuzano-Jost, Annmarie G. Carlton, Douglas A. Day, Glenn S. Diskin, Timothy D. Gordon, Jose L. Jimenez, Daniel A. Lack, Jin Liao, Milos Z. Markovic, Ann M. Middlebrook, Nga L. Ng, Anne E. Perring, Matthews S. Richardson, Joshua P. Schwarz, Rebecca A. Washenfelder, Andre Welti, Lu Xu, Luke D. Ziemba, and Daniel M. Murphy
Atmos. Chem. Phys., 16, 4987–5007,Short summary
Microscopic pollution particles make the atmosphere look hazy and also cool the earth by sending sunlight back to space. When the air is moist, these particles swell with water and scatter even more sunlight. We showed that particles formed from organic material – which dominates particulate pollution in the southeastern U.S. – does not take up water very effectively, toward the low end of most previous studies. We also found a better way to mathematically describe this swelling process.
Charles A. Brock, Nicholas L. Wagner, Bruce E. Anderson, Andreas Beyersdorf, Pedro Campuzano-Jost, Douglas A. Day, Glenn S. Diskin, Timothy D. Gordon, Jose L. Jimenez, Daniel A. Lack, Jin Liao, Milos Z. Markovic, Ann M. Middlebrook, Anne E. Perring, Matthews S. Richardson, Joshua P. Schwarz, Andre Welti, Luke D. Ziemba, and Daniel M. Murphy
Atmos. Chem. Phys., 16, 5009–5019,Short summary
Two research aircraft made dozens of vertical profiles over rural areas in the southeastern US in summer 2013. These measurements show that, in addition to how much pollution was present and how moist the atmosphere was, the size of the pollutant particles affected how much sunlight was reflected back to space. These measurements will help climate modelers determine which characteristics of pollution are important to predict with accuracy.
Robert J. Farrington, Paul J. Connolly, Gary Lloyd, Keith N. Bower, Michael J. Flynn, Martin W. Gallagher, Paul R. Field, Chris Dearden, and Thomas W. Choularton
Atmos. Chem. Phys., 16, 4945–4966,Short summary
This paper assesses the reasons for high ice number concentrations observed in orographic clouds by comparing observations with model simulations over Jungfraujoch, Switzerland. The results suggest that ice nuclei do not significantly contribute to the high concentrations and that a surface source of ice crystals is responsible for the witnessed ice number concentrations.
Fernando Chouza, Oliver Reitebuch, Michael Jähn, Stephan Rahm, and Bernadett Weinzierl
Atmos. Chem. Phys., 16, 4675–4692,Short summary
This study presents the analysis of island induced gravity waves observed by an airborne Doppler wind lidar (DWL). First, the instrumental corrections required for the retrieval vertical wind measurements from an airborne DWL are presented. Then, the method is applied to two case studies to determine, in combination with numerical models and in situ measurements, the main characteristics of the observed waves.
Bernadette Rosati, Erik Herrmann, Silvia Bucci, Federico Fierli, Francesco Cairo, Martin Gysel, Ralf Tillmann, Johannes Größ, Gian Paolo Gobbi, Luca Di Liberto, Guido Di Donfrancesco, Alfred Wiedensohler, Ernest Weingartner, Annele Virtanen, Thomas F. Mentel, and Urs Baltensperger
Atmos. Chem. Phys., 16, 4539–4554,Short summary
We present vertical profiles of aerosol optical properties, which were explored within the planetary boundary layer in a case study in 2012 in the Po Valley region. A comparison of in situ measurements recorded aboard a Zeppelin NT and ground-based remote-sensing data was performed yielding good agreement. Additionally, the role of ambient relative humidity for the aerosol particles' optical properties was investigated.
Emma Järvinen, Karoliina Ignatius, Leonid Nichman, Thomas B. Kristensen, Claudia Fuchs, Christopher R. Hoyle, Niko Höppel, Joel C. Corbin, Jill Craven, Jonathan Duplissy, Sebastian Ehrhart, Imad El Haddad, Carla Frege, Hamish Gordon, Tuija Jokinen, Peter Kallinger, Jasper Kirkby, Alexei Kiselev, Karl-Heinz Naumann, Tuukka Petäjä, Tamara Pinterich, Andre S. H. Prevot, Harald Saathoff, Thea Schiebel, Kamalika Sengupta, Mario Simon, Jay G. Slowik, Jasmin Tröstl, Annele Virtanen, Paul Vochezer, Steffen Vogt, Andrea C. Wagner, Robert Wagner, Christina Williamson, Paul M. Winkler, Chao Yan, Urs Baltensperger, Neil M. Donahue, Rick C. Flagan, Martin Gallagher, Armin Hansel, Markku Kulmala, Frank Stratmann, Douglas R. Worsnop, Ottmar Möhler, Thomas Leisner, and Martin Schnaiter
Atmos. Chem. Phys., 16, 4423–4438,
Christopher R. Hoyle, Clare S. Webster, Harald E. Rieder, Athanasios Nenes, Emanuel Hammer, Erik Herrmann, Martin Gysel, Nicolas Bukowiecki, Ernest Weingartner, Martin Steinbacher, and Urs Baltensperger
Atmos. Chem. Phys., 16, 4043–4061,Short summary
A simple statistical model to predict the number of aerosols which activate to form cloud droplets in warm clouds has been established, based on regression analysis of data from the high-altitude site Jungfraujoch. It is found that cloud droplet formation at the Jungfraujoch is predominantly controlled by the number concentration of aerosol particles. A statistical model based on only the number of particles larger than 80nm can explain 79 % of the observed variance in droplet numbers.
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,Short summary
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.
Cenlin He, Qinbin Li, Kuo-Nan Liou, Ling Qi, Shu Tao, and Joshua P. Schwarz
Atmos. Chem. Phys., 16, 3077–3098,Short summary
Blarck carbon aging significantly affects its global distribution and thus climatic effects. This study develops a microphysics-based BC aging scheme in a global model, which substantially improves model simulations of BC over the remote Pacific. The microphysical scheme shows fast aging over source regions and much slower aging in remote regions. The microphysical aging significantly reduces global BC burden and lifetime, showing important implications for the estimate of BC radiative effects.
J. D. Lee, L. K. Whalley, D. E. Heard, D. Stone, R. E. Dunmore, J. F. Hamilton, D. E. Young, J. D. Allan, S. Laufs, and J. Kleffmann
Atmos. Chem. Phys., 16, 2747–2764,Short summary
This paper presents field measurements of HONO and a range of other gas phase and particulate species from an urban background site in London. The measured daytime HONO cannot be reproduced with a simple box model and thus a significant daytime missing source of HONO is present. We show that this missing source could be responsible for 40 % of the OH radical source and 57 % of the OH initiation; hence its potential importance for atmospheric oxidation and ozone production.
Louis Marelle, Jennie L. Thomas, Jean-Christophe Raut, Kathy S. Law, Jukka-Pekka Jalkanen, Lasse Johansson, Anke Roiger, Hans Schlager, Jin Kim, Anja Reiter, and Bernadett Weinzierl
Atmos. Chem. Phys., 16, 2359–2379,
I. Crawford, G. Lloyd, E. Herrmann, C. R. Hoyle, K. N. Bower, P. J. Connolly, M. J. Flynn, P. H. Kaye, T. W. Choularton, and M. W. Gallagher
Atmos. Chem. Phys., 16, 2273–2284,Short summary
In this manuscript we discuss observations of fluorescent aerosol and their interactions with cloud at a high-alpine site in the wintertime under background conditions. We find the majority of the fluorescent aerosol to be consistent in nature to mineral dust and no apparent trend was observed between the fluorescent aerosol fraction and meteorological or cloud microphysical parameters, suggesting that particle fluorescence does not impact cloud evolution or formation at the site.
Robert Wagner, Alexei Kiselev, Ottmar Möhler, Harald Saathoff, and Isabelle Steinke
Atmos. Chem. Phys., 16, 2025–2042,Short summary
We have investigated the enhancement of the ice nucleation ability of well-known and abundant ice nucleating particles like dust grains due to pre-activation. Temporary exposure to a low temperature (228 K) provokes that pores and surface cracks of the particles are filled with ice, which makes them better nuclei for the growth of macroscopic ice crystals at high temperatures (245–260 K).
C. R. Hoyle, C. Fuchs, E. Järvinen, H. Saathoff, A. Dias, I. El Haddad, M. Gysel, S. C. Coburn, J. Tröstl, A.-K. Bernhammer, F. Bianchi, M. Breitenlechner, J. C. Corbin, J. Craven, N. M. Donahue, J. Duplissy, S. Ehrhart, C. Frege, H. Gordon, N. Höppel, M. Heinritzi, T. B. Kristensen, U. Molteni, L. Nichman, T. Pinterich, A. S. H. Prévôt, M. Simon, J. G. Slowik, G. Steiner, A. Tomé, A. L. Vogel, R. Volkamer, A. C. Wagner, R. Wagner, A. S. Wexler, C. Williamson, P. M. Winkler, C. Yan, A. Amorim, J. Dommen, J. Curtius, M. W. Gallagher, R. C. Flagan, A. Hansel, J. Kirkby, M. Kulmala, O. Möhler, F. Stratmann, D. R. Worsnop, and U. Baltensperger
Atmos. Chem. Phys., 16, 1693–1712,Short summary
A significant portion of sulphate, an important constituent of atmospheric aerosols, is formed via the aqueous phase oxidation of sulphur dioxide by ozone. The rate of this reaction has previously only been measured over a relatively small temperature range. Here, we use the state of the art CLOUD chamber at CERN to perform the first measurements of this reaction rate in super-cooled droplets, confirming that the existing extrapolation of the reaction rate to sub-zero temperatures is accurate.
L. Xu, L. R. Williams, D. E. Young, J. D. Allan, H. Coe, P. Massoli, E. Fortner, P. Chhabra, S. Herndon, W. A. Brooks, J. T. Jayne, D. R. Worsnop, A. C. Aiken, S. Liu, K. Gorkowski, M. K. Dubey, Z. L. Fleming, S. Visser, A. S. H. Prévôt, and N. L. Ng
Atmos. Chem. Phys., 16, 1139–1160,Short summary
We investigate the spatial distribution of submicron aerosol in the greater London area as part of the Clean Air for London (ClearfLo) project in winter 2012. Although the concentrations of organic aerosol (OA) are similar between a rural and an urban site, the OA sources are different. We also examine the volatility of submicron aerosol at the rural site and find that the non-volatile organics have similar sources or have undergone similar chemical processing as refractory black carbon.
J. W. Taylor, T. W. Choularton, A. M. Blyth, Z. Liu, K. N. Bower, J. Crosier, M. W. Gallagher, P. I. Williams, J. R. Dorsey, M. J. Flynn, L. J. Bennett, Y. Huang, J. French, A. Korolev, and P. R. A. Brown
Atmos. Chem. Phys., 16, 799–826,Short summary
We present microphysical observations of cumulus clouds measured over south-west England during COPE in summer 2013. Detailed sampling focused on an isolated liquid cloud that glaciated as it matured to merge with a band of cloud downwind. The first ice particles observed were frozen drizzle, while columnar ice dominated in the mature stages. We discuss the interactions between the warm rain and secondary ice processes, and their importance for the formation of precipitation.
P. Vochezer, E. Järvinen, R. Wagner, P. Kupiszewski, T. Leisner, and M. Schnaiter
Atmos. Meas. Tech., 9, 159–177,Short summary
To study clouds constituting of liquid droplets as well as ice particles we used the latest versions of the Small Ice Detector which record high resolution scattering patterns of individual small cloud particles. In the case of a droplet its precise size is obtained and for ice particles its shape is deduced from the scattering pattern.We present results from artificial clouds at the AIDA cloud chamber and natural clouds probed at a mountain top station as well as from an aircraft in the arctic.
G. Lloyd, T. W. Choularton, K. N. Bower, M. W. Gallagher, P. J. Connolly, M. Flynn, R. Farrington, J. Crosier, O. Schlenczek, J. Fugal, and J. Henneberger
Atmos. Chem. Phys., 15, 12953–12969,Short summary
The paper explores the microphysical structure of clouds at the high-alpine measurement site Jungfraujoch, Switzerland. High concentrations of ice crystals were measured by a range of instruments. The presence of these high concentrations could not be explained through conventional understanding of ice formation processes in clouds and the possibility that the surface provides a significant source of ice crystals is investigated.
M. Paramonov, V.-M. Kerminen, M. Gysel, P. P. Aalto, M. O. Andreae, E. Asmi, U. Baltensperger, A. Bougiatioti, D. Brus, G. P. Frank, N. Good, S. S. Gunthe, L. Hao, M. Irwin, A. Jaatinen, Z. Jurányi, S. M. King, A. Kortelainen, A. Kristensson, H. Lihavainen, M. Kulmala, U. Lohmann, S. T. Martin, G. McFiggans, N. Mihalopoulos, A. Nenes, C. D. O'Dowd, J. Ovadnevaite, T. Petäjä, U. Pöschl, G. C. Roberts, D. Rose, B. Svenningsson, E. Swietlicki, E. Weingartner, J. Whitehead, A. Wiedensohler, C. Wittbom, and B. Sierau
Atmos. Chem. Phys., 15, 12211–12229,Short summary
The research paper presents the first comprehensive overview of field measurements with the CCN Counter performed at a large number of locations around the world within the EUCAARI framework. The paper sheds light on the CCN number concentrations and activated fractions around the world and their dependence on the water vapour supersaturation ratio, the dependence of aerosol hygroscopicity on particle size, and seasonal and diurnal variation of CCN activation and hygroscopic properties.
J. C. Corbin, A. Othman, J. D. Allan, D. R. Worsnop, J. D. Haskins, B. Sierau, U. Lohmann, and A. A. Mensah
Atmos. Meas. Tech., 8, 4615–4636,Short summary
Peak-integration uncertainties in the Aerodyne high-resolution aerosol mass spectrometer (AMS) are analyzed in detail using a combination of empirical data analysis and Monte Carlo approaches. The most general conclusion, applicable to any mass spectrometer, is that non-zero mass accuracy leads to a percentage error in constrained peak fits, even for well-resolved peaks. For overlapping peaks, this mass-accuracy effect may be viewed as a reduction in the effective m/z-calibration precision.
W. W. Hu, P. Campuzano-Jost, B. B. Palm, D. A. Day, A. M. Ortega, P. L. Hayes, J. E. Krechmer, Q. Chen, M. Kuwata, Y. J. Liu, S. S. de Sá, K. McKinney, S. T. Martin, M. Hu, S. H. Budisulistiorini, M. Riva, J. D. Surratt, J. M. St. Clair, G. Isaacman-Van Wertz, L. D. Yee, A. H. Goldstein, S. Carbone, J. Brito, P. Artaxo, J. A. de Gouw, A. Koss, A. Wisthaler, T. Mikoviny, T. Karl, L. Kaser, W. Jud, A. Hansel, K. S. Docherty, M. L. Alexander, N. H. Robinson, H. Coe, J. D. Allan, M. R. Canagaratna, F. Paulot, and J. L. Jimenez
Atmos. Chem. Phys., 15, 11807–11833,Short summary
This work summarized all the studies reporting isoprene epoxydiols-derived secondary organic aerosol (IEPOX-SOA) measured globally by aerosol mass spectrometer and compare them with modeled gas-phase IEPOX, with results suggestive of the importance of IEPOX-SOA for regional and global OA budgets. A real-time tracer of IEPOX-SOA is thoroughly evaluated for the first time by combing multiple field and chamber studies. A quick and easy empirical method on IEPOX-SOA estimation is also presented.
D. Liu, B. Quennehen, E. Darbyshire, J. D. Allan, P. I. Williams, J. W. Taylor, S. J.-B. Bauguitte, M. J. Flynn, D. Lowe, M. W. Gallagher, K. N. Bower, T. W. Choularton, and H. Coe
Atmos. Chem. Phys., 15, 11537–11555,Short summary
We show that during the springtime of 2013, the anthropogenic pollution particularly from sources in Asia, contributed significantly to black carbon across the European Arctic free troposphere. In contrast to previous studies, the contribution from open wildfires was minimal. Given that Asian pollution is likely to continue to rise over the coming years, it is likely that the radiative forcing in the Arctic will also continue to increase.
R. Fröhlich, M. J. Cubison, J. G. Slowik, N. Bukowiecki, F. Canonaco, P. L. Croteau, M. Gysel, S. Henne, E. Herrmann, J. T. Jayne, M. Steinbacher, D. R. Worsnop, U. Baltensperger, and A. S. H. Prévôt
Atmos. Chem. Phys., 15, 11373–11398,Short summary
This manuscript presents the first long-term (14-month) and highly time-resolved (10 min) measurements of NR-PM1 aerosol chemical composition at a high-altitude site (JFJ, Switzerland, 3580m a.s.l.). The elevated location allowed the investigation of free tropospheric aerosol year round. Total and relative mass loadings, diurnal variations as well as seasonal variations are discussed together with geographical origin, organic aerosol sources and the influence of the planetary boundary layer.
S. Visser, J. G. Slowik, M. Furger, P. Zotter, N. Bukowiecki, F. Canonaco, U. Flechsig, K. Appel, D. C. Green, A. H. Tremper, D. E. Young, P. I. Williams, J. D. Allan, H. Coe, L. R. Williams, C. Mohr, L. Xu, N. L. Ng, E. Nemitz, J. F. Barlow, C. H. Halios, Z. L. Fleming, U. Baltensperger, and A. S. H. Prévôt
Atmos. Chem. Phys., 15, 11291–11309,Short summary
Trace element measurements in three particle size ranges (PM10-2.5, PM2.5-1.0 and PM1.0-0.3) were performed with 2h time resolution at kerbside, urban background and rural sites during the ClearfLo winter 2012 campaign in London. The environment-dependent variability of emissions was characterized using the Multilinear Engine implementation of the positive matrix factorization model. A total of nine different factors were resolved from local, regional and natural origin.
S. Groß, V. Freudenthaler, K. Schepanski, C. Toledano, A. Schäfler, A. Ansmann, and B. Weinzierl
Atmos. Chem. Phys., 15, 11067–11080,Short summary
In June and July 2013 dual-wavelength lidar measurements were performed in Barbados to study long-range transported Saharan dust across the Atlantic Ocean and investigate transport-induced changes. The focus of our measurements is the intensive optical properties, the lidar ratio and the particle linear depolarization ratio. While the lidar ratio shows no differences compared to the values of fresh Saharan dust, the particle linear depolarization ratio shows slight differences.
P. S. Kim, D. J. Jacob, J. A. Fisher, K. Travis, K. Yu, L. Zhu, R. M. Yantosca, M. P. Sulprizio, J. L. Jimenez, P. Campuzano-Jost, K. D. Froyd, J. Liao, J. W. Hair, M. A. Fenn, C. F. Butler, N. L. Wagner, T. D. Gordon, A. Welti, P. O. Wennberg, J. D. Crounse, J. M. St. Clair, A. P. Teng, D. B. Millet, J. P. Schwarz, M. Z. Markovic, and A. E. Perring
Atmos. Chem. Phys., 15, 10411–10433,
G. Vali, P. J. DeMott, O. Möhler, and T. F. Whale
Atmos. Chem. Phys., 15, 10263–10270,Short summary
Clarification is needed in the terminology used to discuss ice nucleation in the literature. Conflicting interpretations coupled with uncertainties about the details of the processes have led to difficulties in the clear communication of results and ideas. This paper contains a proposal for future usage. This proposed terminology was arrived at as a result of a year-long exchange of suggestions by a number of scientists.
J. Diab, T. Streibel, F. Cavalli, S. C. Lee, H. Saathoff, A. Mamakos, J. C. Chow, L.-W. A. Chen, J. G. Watson, O. Sippula, and R. Zimmermann
Atmos. Meas. Tech., 8, 3337–3353,Short summary
This paper depicts several fields of application of a new analytical method, which expands the well-established EC/OC method, which enables one to measure the carbon content (organic and elemental) of particulate aerosols. It was coupled to photo-ionization mass spectrometry to get structural information of the evolving carbonaceous species. Application fields such as smoke chamber-, ambient - and wood combustion particles were addressed, covering exemplary primary and secondary aerosol sources.
P. Kupiszewski, E. Weingartner, P. Vochezer, M. Schnaiter, A. Bigi, M. Gysel, B. Rosati, E. Toprak, S. Mertes, and U. Baltensperger
Atmos. Meas. Tech., 8, 3087–3106,
J. Meyer, C. Rolf, C. Schiller, S. Rohs, N. Spelten, A. Afchine, M. Zöger, N. Sitnikov, T. D. Thornberry, A. W. Rollins, Z. Bozóki, D. Tátrai, V. Ebert, B. Kühnreich, P. Mackrodt, O. Möhler, H. Saathoff, K. H. Rosenlof, and M. Krämer
Atmos. Chem. Phys., 15, 8521–8538,
E. Athanasopoulou, A. P. Protonotariou, E. Bossioli, A. Dandou, M. Tombrou, J. D. Allan, H. Coe, N. Mihalopoulos, J. Kalogiros, A. Bacak, J. Sciare, and G. Biskos
Atmos. Chem. Phys., 15, 8401–8421,Short summary
A model system is evaluated versus ground and airborne aerosol measurements, towards the identification of its competencies and deficiencies over the eastern Mediterranean (EM) during summer. Secondary organic aerosol (OA) formation is investigated towards improving OA behaviour. Biomass burning is a significant particle source, largely explaining OA underestimation (ca. 50%). More than 70% of the aerosol mass over the EM is related to trans-boundary transport during strong northeastern winds.
F. Chouza, O. Reitebuch, S. Groß, S. Rahm, V. Freudenthaler, C. Toledano, and B. Weinzierl
Atmos. Meas. Tech., 8, 2909–2926,
J. Liu, E. Scheuer, J. Dibb, G. S. Diskin, L. D. Ziemba, K. L. Thornhill, B. E. Anderson, A. Wisthaler, T. Mikoviny, J. J. Devi, M. Bergin, A. E. Perring, M. Z. Markovic, J. P. Schwarz, P. Campuzano-Jost, D. A. Day, J. L. Jimenez, and R. J. Weber
Atmos. Chem. Phys., 15, 7841–7858,Short summary
Brown carbon (BrC) is found throughout the US continental troposphere during a summer of extensive biomass burning and its prevalence relative to black carbon (BC) increases with altitude. A radiative transfer model based on direct measurements of aerosol scattering and absorption by BC and BrC shows BrC reduces top-of-atmosphere forcing by 20%. A method to estimate BrC radiative forcing efficiencies from surface-based measurements is provided.
P. Zieger, P. P. Aalto, V. Aaltonen, M. Äijälä, J. Backman, J. Hong, M. Komppula, R. Krejci, M. Laborde, J. Lampilahti, G. de Leeuw, A. Pfüller, B. Rosati, M. Tesche, P. Tunved, R. Väänänen, and T. Petäjä
Atmos. Chem. Phys., 15, 7247–7267,Short summary
The effect of water uptake (hygroscopicity) on aerosol light scattering properties is generally lower for boreal aerosol due to the dominance of organic substances. A columnar optical closure study using ground-based and airborne measurements of aerosol optical, chemical and microphysical properties was conducted and the implications and limitations are discussed.
N. L. Wagner, C. A. Brock, W. M. Angevine, A. Beyersdorf, P. Campuzano-Jost, D. Day, J. A. de Gouw, G. S. Diskin, T. D. Gordon, M. G. Graus, J. S. Holloway, G. Huey, J. L. Jimenez, D. A. Lack, J. Liao, X. Liu, M. Z. Markovic, A. M. Middlebrook, T. Mikoviny, J. Peischl, A. E. Perring, M. S. Richardson, T. B. Ryerson, J. P. Schwarz, C. Warneke, A. Welti, A. Wisthaler, L. D. Ziemba, and D. M. Murphy
Atmos. Chem. Phys., 15, 7085–7102,Short summary
This paper investigates the summertime vertical profile of aerosol over the southeastern US using in situ measurements collected from aircraft. We use a vertical mixing model and measurements of CO to predict the vertical profile of aerosol that we would expect from vertical mixing alone and compare with the observed aerosol profile. We found a modest enhancement of aerosol in the cloudy transition layer during shallow cumulus convection and attribute the enhancement to local aerosol formation.
M. J. Alvarado, C. R. Lonsdale, R. J. Yokelson, S. K. Akagi, H. Coe, J. S. Craven, E. V. Fischer, G. R. McMeeking, J. H. Seinfeld, T. Soni, J. W. Taylor, D. R. Weise, and C. E. Wold
Atmos. Chem. Phys., 15, 6667–6688,Short summary
Being able to understand and simulate the chemical evolution of biomass burning smoke plumes under a wide variety of conditions is a critical part of forecasting the impact of these fires on air quality, atmospheric composition, and climate. Here we use an improved model of this chemistry to simulate the evolution of ozone and secondary organic aerosol within a young biomass burning smoke plume from the Williams prescribed burn in chaparral, which was sampled over California in November 2009.
P. Amato, M. Joly, C. Schaupp, E. Attard, O. Möhler, C. E. Morris, Y. Brunet, and A.-M. Delort
Atmos. Chem. Phys., 15, 6455–6465,Short summary
Mortality rate of typical bacterial aerosols (Pseudomonas species) was determined in a cloud simulation chamber. Ice nucleation activity remained unchanged for several hours in aerosolized cells, whether they were viable or not. Cloud increased the specific removal of ice nucleation active cells by precipitation. Survival was negatively impacted by the presence of cloud and by sulfates.
D. E. Young, J. D. Allan, P. I. Williams, D. C. Green, M. J. Flynn, R. M. Harrison, J. Yin, M. W. Gallagher, and H. Coe
Atmos. Chem. Phys., 15, 6351–6366,Short summary
For the first time, the behaviour of non-refractory inorganic and organic submicron particulates through an entire annual cycle is investigated at a UK urban background site. We show secondary aerosols account for a significant fraction of the submicron aerosol burden, high concentration events are governed by different factors depending on season, and on an annual basis there is no variability in the extent of secondary organic aerosol oxidation.
M. Hummel, C. Hoose, M. Gallagher, D. A. Healy, J. A. Huffman, D. O'Connor, U. Pöschl, C. Pöhlker, N. H. Robinson, M. Schnaiter, J. R. Sodeau, M. Stengel, E. Toprak, and H. Vogel
Atmos. Chem. Phys., 15, 6127–6146,
J. D. Allan, P. I. Williams, J. Najera, J. D. Whitehead, M. J. Flynn, J. W. Taylor, D. Liu, E. Darbyshire, L. J. Carpenter, R. Chance, S. J. Andrews, S. C. Hackenberg, and G. McFiggans
Atmos. Chem. Phys., 15, 5599–5609,Short summary
New particle formation (NPF) is an important contributor to aerosol number concentrations in the Arctic and thus has a major role in dictating cloud properties and climate in this region. Here we present direct evidence that the oxidation of iodine in the atmosphere causes NPF in the Greenland Sea. This is important because this is a NPF mechanism that has not previously been considered in modelling studies at these latitudes.
J. W. Taylor, J. D. Allan, D. Liu, M. Flynn, R. Weber, X. Zhang, B. L. Lefer, N. Grossberg, J. Flynn, and H. Coe
Atmos. Meas. Tech., 8, 1701–1718,Short summary
When using the SP2 to report black carbon core/shell coating thickness, the core density and refractive index must be estimated from literature values. We systematically vary the assumed parameters and the instrument calibration, and quantify the effects in the derived coatings. The technique is highly sensitive to the core refractive index but has only a minor sensitivity to the core density and coating refractive index. We identify the most appropriate values to use in future analysis.
Q. Chen, D. K. Farmer, L. V. Rizzo, T. Pauliquevis, M. Kuwata, T. G. Karl, A. Guenther, J. D. Allan, H. Coe, M. O. Andreae, U. Pöschl, J. L. Jimenez, P. Artaxo, and S. T. Martin
Atmos. Chem. Phys., 15, 3687–3701,Short summary
Submicron particle mass concentration in the Amazon during the wet season of 2008 was dominated by organic material. The PMF analysis finds a comparable importance of gas-phase (gas-to-particle condensation) and particle-phase (reactive uptake of isoprene oxidation products, especially of epoxydiols to acidic haze, fog, or cloud droplets) production of secondary organic material during the study period, together accounting for >70% of the organic-particle mass concentration.
I. Steinke, C. Hoose, O. Möhler, P. Connolly, and T. Leisner
Atmos. Chem. Phys., 15, 3703–3717,Short summary
Ice nucleation in clouds has a significant influence on the global radiative budget and the hydrological cycle. Several studies have investigated the ice formation in droplets and parameterizations have been developed in order to include immersion freezing in climate models. In contrast, there are fewer studies regarding the conversion of water vapor into ice (so-called deposition nucleation) which is the topic of this paper which investigates deposition nucleation by Arizona Test dust in detail
L. R. Crilley, W. J. Bloss, J. Yin, D. C. S. Beddows, R. M. Harrison, J. D. Allan, D. E. Young, M. Flynn, P. Williams, P. Zotter, A. S. H. Prevot, M. R. Heal, J. F. Barlow, C. H. Halios, J. D. Lee, S. Szidat, and C. Mohr
Atmos. Chem. Phys., 15, 3149–3171,Short summary
Wood is a renewable fuel but its combustion for residential heating releases a number of locally acting air pollutants, most notably particulate matter known to have adverse effects on human health. This paper used chemical tracers for wood smoke to estimate the contribution that burning wood makes to concentrations of airborne particles in the atmosphere of southern England and most particularly in London.
M. D. Jolleys, H. Coe, G. McFiggans, J. W. Taylor, S. J. O'Shea, M. Le Breton, S. J.-B. Bauguitte, S. Moller, P. Di Carlo, E. Aruffo, P. I. Palmer, J. D. Lee, C. J. Percival, and M. W. Gallagher
Atmos. Chem. Phys., 15, 3077–3095,Short summary
Particulate emissions in the form of organic aerosol from boreal forest fires in Canada have been measured during an aircraft measurement campaign. Ratios of the amount of aerosol emitted relative to gas species such as CO were calculated and show high levels of variability throughout the campaign. This variability is affected by both changes in fire conditions, as fires tended to die down later in the measurement period, and by changes to the aerosol due to chemical reactions in the atmosphere.
S. Archer-Nicholls, D. Lowe, E. Darbyshire, W. T. Morgan, M. M. Bela, G. Pereira, J. Trembath, J. W. Kaiser, K. M. Longo, S. R. Freitas, H. Coe, and G. McFiggans
Geosci. Model Dev., 8, 549–577,Short summary
The regional WRF-Chem model was used to study aerosol particles from biomass burning in South America. The modelled estimates of fire plume injection heights were found to be too high, with serious implications for modelled aerosol vertical distribution, transport and impacts on local climate. A modified emission scenario was developed which improved the predicted injection height. Model results were compared and evaluated against in situ measurements from the 2012 SAMBBA flight campaign.
N. Hiranuma, S. Augustin-Bauditz, H. Bingemer, C. Budke, J. Curtius, A. Danielczok, K. Diehl, K. Dreischmeier, M. Ebert, F. Frank, N. Hoffmann, K. Kandler, A. Kiselev, T. Koop, T. Leisner, O. Möhler, B. Nillius, A. Peckhaus, D. Rose, S. Weinbruch, H. Wex, Y. Boose, P. J. DeMott, J. D. Hader, T. C. J. Hill, Z. A. Kanji, G. Kulkarni, E. J. T. Levin, C. S. McCluskey, M. Murakami, B. J. Murray, D. Niedermeier, M. D. Petters, D. O'Sullivan, A. Saito, G. P. Schill, T. Tajiri, M. A. Tolbert, A. Welti, T. F. Whale, T. P. Wright, and K. Yamashita
Atmos. Chem. Phys., 15, 2489–2518,Short summary
Seventeen ice nucleation measurement techniques contributed to investigate the immersion freezing behavior of illite NX. All data showed a similar temperature trend, but the measured ice nucleation activity was on average smaller for the wet suspended samples and higher for the dry-dispersed aerosol samples at high temperatures. A continued investigation and collaboration is necessary to obtain further insights into consistency or diversity of ice nucleation measurements.
D. E. Young, J. D. Allan, P. I. Williams, D. C. Green, R. M. Harrison, J. Yin, M. J. Flynn, M. W. Gallagher, and H. Coe
Atmos. Chem. Phys., 15, 2429–2443,Short summary
Two solid fuel organic aerosol (SFOA) factors, both associated with domestic space heating activities, were derived from positive matrix factorisation (PMF) applied to organic aerosol data from an aerosol mass spectrometer (AMS) deployed at an urban background site in London during winter 2012. The factors controlling the split between the two SFOA factors were assessed, and it is concluded the split is likely governed predominantly by differences in burn conditions.
S. Visser, J. G. Slowik, M. Furger, P. Zotter, N. Bukowiecki, R. Dressler, U. Flechsig, K. Appel, D. C. Green, A. H. Tremper, D. E. Young, P. I. Williams, J. D. Allan, S. C. Herndon, L. R. Williams, C. Mohr, L. Xu, N. L. Ng, A. Detournay, J. F. Barlow, C. H. Halios, Z. L. Fleming, U. Baltensperger, and A. S. H. Prévôt
Atmos. Chem. Phys., 15, 2367–2386,Short summary
Ambient concentrations of trace elements with 2h time resolution were measured in three size ranges (PM10–2.5, PM2.5–1.0, PM1.0–0.3) at kerbside, urban background and rural sites in London during the ClearfLo (Clean Air for London) field campaign. Quantification of kerb and urban increments, and assessment of diurnal and weekly variability provided insight into sources governing urban air quality and the effects of urban micro-environments on human exposure.
J. Yin, S. A. Cumberland, R. M. Harrison, J. Allan, D. E. Young, P. I. Williams, and H. Coe
Atmos. Chem. Phys., 15, 2139–2158,Short summary
Breathing particles from polluted air is known to cause increased health complaints and higher death rates. Airborne particles come from a range of sources; in order to implement cost-effective control measures, it is necessary to understand the amount contributed by each. In this paper, two advanced procedures for estimating the contributions of particle sources in London are compared with one another, revealing a wide range of sources including traffic, woodsmoke and cooking particles.
B. Rosati, G. Wehrle, M. Gysel, P. Zieger, U. Baltensperger, and E. Weingartner
Atmos. Meas. Tech., 8, 921–939,Short summary
Only few measurements focused on vertical profiles of aerosol hygroscopic and optical properties in airborne studies. For this purpose the white-light optical particle spectrometer (WHOPS) was developed. It allows a relatively fast measurement of the particles hygroscopicity, mixing state and index of refraction of particles in the optically relevant size range. This paper presents a detailed technical description and characterization of the WHOPS and first results from the field.
P. Panteliadis, T. Hafkenscheid, B. Cary, E. Diapouli, A. Fischer, O. Favez, P. Quincey, M. Viana, R. Hitzenberger, R. Vecchi, D. Saraga, J. Sciare, J. L. Jaffrezo, A. John, J. Schwarz, M. Giannoni, J. Novak, A. Karanasiou, P. Fermo, and W. Maenhaut
Atmos. Meas. Tech., 8, 779–792,
K. M. Sakamoto, J. D. Allan, H. Coe, J. W. Taylor, T. J. Duck, and J. R. Pierce
Atmos. Chem. Phys., 15, 1633–1646,
C. G. Schmitt, J. D. All, J. P. Schwarz, W. P. Arnott, R. J. Cole, E. Lapham, and A. Celestian
The Cryosphere, 9, 331–340,Short summary
This paper presents the results of 3 years of measurements of light absorbing particles on the glaciers in Peru. A new analysis technique has been developed and results are shown to be well correlated with black carbon mass estimates made with the Single Particle Soot Photometer (SP2) instrument, the state-of-the-art instrument for this type of measurement. Effective black carbon levels were found to be moderate on glaciers near cities and close to zero in more remote regions.
H. Wex, S. Augustin-Bauditz, Y. Boose, C. Budke, J. Curtius, K. Diehl, A. Dreyer, F. Frank, S. Hartmann, N. Hiranuma, E. Jantsch, Z. A. Kanji, A. Kiselev, T. Koop, O. Möhler, D. Niedermeier, B. Nillius, M. Rösch, D. Rose, C. Schmidt, I. Steinke, and F. Stratmann
Atmos. Chem. Phys., 15, 1463–1485,Short summary
Immersion freezing measurements from seven different measurement techniques were intercompared using a biological ice nucleating material from bacteria. Although different techniques examined differently concentrated droplets, it was possible to find a uniform description, which showed that results from all experiments were generally in good agreement and were also in agreement with parameterizations published earlier in literature.
D. Lowe, S. Archer-Nicholls, W. Morgan, J. Allan, S. Utembe, B. Ouyang, E. Aruffo, M. Le Breton, R. A. Zaveri, P. Di Carlo, C. Percival, H. Coe, R. Jones, and G. McFiggans
Atmos. Chem. Phys., 15, 1385–1409,
W. T. Morgan, B. Ouyang, J. D. Allan, E. Aruffo, P. Di Carlo, O. J. Kennedy, D. Lowe, M. J. Flynn, P. D. Rosenberg, P. I. Williams, R. Jones, G. B. McFiggans, and H. Coe
Atmos. Chem. Phys., 15, 973–990,Short summary
This paper used observations from a research aircraft flying around the UK to investigate how air pollution in north-western Europe can alter nighttime chemical reactions in the atmosphere. These chemical reactions can worsen air quality in the region, as well as influence regional climate change. Ammonium nitrate aerosol appears to play an important role. The paper indicates that representation of these chemical reactions is poorly represented in models used for air quality and climate.
P. J. DeMott, A. J. Prenni, G. R. McMeeking, R. C. Sullivan, M. D. Petters, Y. Tobo, M. Niemand, O. Möhler, J. R. Snider, Z. Wang, and S. M. Kreidenweis
Atmos. Chem. Phys., 15, 393–409,Short summary
Laboratory and field data are used together to develop an empirical relation between the concentrations of mineral dust particles at sizes above 0.5 microns, approximated as a single compositional type, and ice nucleating particle concentrations measured versus temperature. This should be useful in global modeling of ice cloud formation. The utility of laboratory data for parameterization development is reinforced, and the need for careful interpretation of ice nucleation data is emphasized.
J. W. Taylor, J. D. Allan, G. Allen, H. Coe, P. I. Williams, M. J. Flynn, M. Le Breton, J. B. A. Muller, C. J. Percival, D. Oram, G. Forster, J. D. Lee, A. R. Rickard, M. Parrington, and P. I. Palmer
Atmos. Chem. Phys., 14, 13755–13771,Short summary
We present a case study of BC wet removal by examining aerosol properties in three biomass burning plumes, one of which passed through a precipitating cloud. Nucleation scavenging preferentially removed the largest and most coated BC-containing particles. Calculated single-scattering albedo (SSA) showed little variation, as a large number of non-BC particles were also present in the precipitation-affected plume.