Articles | Volume 21, issue 4
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Aqueous-phase behavior of glyoxal and methylglyoxal observed with carbon and oxygen K-edge X-ray absorption spectroscopy
Nano and Molecular Systems Research Unit, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland
Jack J. Lin
Nano and Molecular Systems Research Unit, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland
Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
Nano and Molecular Systems Research Unit, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland
Institute for Molecular Science, Myodaiji, Okazaki 444-8585, Japan
Department of Chemistry and Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, P.O. Box 55, 00014 Helsinki, Finland
Nano and Molecular Systems Research Unit, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland
No articles found.
Minjie Zheng, Hongyu Liu, Florian Adolphi, Raimund Muscheler, Zhengyao Lu, Mousong Wu, and Nønne L. Prisle
Geosci. Model Dev., 16, 7037–7057,Short summary
The radionuclides 7Be and 10Be are useful tracers for atmospheric transport studies. Here we use the GEOS-Chem to simulate 7Be and 10Be with different production rates: the default production rate in GEOS-Chem and two from the state-of-the-art beryllium production model. We demonstrate that reduced uncertainties in the production rates can enhance the utility of 7Be and 10Be as tracers for evaluating transport and scavenging processes in global models.
Lukas Pichelstorfer, Pontus Roldin, Matti Rissanen, Noora Hyttinen, Olga Garmash, Carlton Xavier, Putian Zhou, Petri Clusius, Benjamin Foreback, Thomas Golin Almeida, Chenjuan Deng, Metin Baykara, Theo Kurten, and Michael Boy
Secondary organic aerosols (SOA) form effectively from gaseous precursors via a process called autoxidation. While key chemical reaction types seem to be known, no general description of autoxidation chemistry exists. In the present work, we present a method to create autoxidation chemistry schemes for any atmospherically relevant hydrocarbon. We exemplarily investigate benzene and its potential to form aerosols. We found that autoxidation, under some conditions, can dominate the SOA formation.
Huan Yang, Ivo Neefjes, Valtteri Tikkanen, Jakub Kubečka, Theo Kurtén, Hanna Vehkamäki, and Bernhard Reischl
Atmos. Chem. Phys., 23, 5993–6009,Short summary
We present a new analytical model for collision rates between molecules and clusters of arbitrary sizes, accounting for long-range interactions. The model is verified against atomistic simulations of typical acid–base clusters participating in atmospheric new particle formation (NPF). Compared to non-interacting models, accounting for long-range interactions leads to 2–3 times higher collision rates for small clusters, indicating the necessity of including such interactions in NPF modeling.
Melissa Meder, Otso Peräkylä, Jonathan G. Varelas, Jingyi Luo, Runlong Cai, Yanjun Zhang, Theo Kurtén, Matthieu Riva, Matti Rissanen, Franz M. Geiger, Regan J. Thomson, and Mikael Ehn
Atmos. Chem. Phys., 23, 4373–4390,Short summary
We discuss and show the viability of a method where multiple isotopically labelled precursors are used for probing the formation pathways of highly oxygenated organic molecules (HOMs) from the oxidation of the monoterpene a-pinene. HOMs are very important for secondary organic aerosol (SOA) formation in forested regions, and monoterpenes are the single largest source of SOA globally. The fast reactions forming HOMs have thus far remained elusive despite considerable efforts over the last decade.
Gargi Sengupta, Minjie Zheng, and Nønne L. Prisle
The effect of organic acid aerosol on sulfur chemistry and cloud properties was investigated in an atmospheric model. Organic acid dissociation was considered using both bulk and surface related properties. We found that organic acid dissociation leads to increased hydrogen ion concentrations and sulfate aerosol mass in aqueous aerosols, increasing cloud formation. This could be important in large scale climate models as many organic aerosol components are both acidic and surface-active.
Sampo Vepsäläinen, Silvia M. Calderón, and Nønne L. Prisle
Atmospheric aerosols act as seeds for cloud formation. Many aerosols contain surface active material that accumulates at the surface of growing droplets. This can affect cloud droplet activation, but the broad significance of the effect and the best way to model it are still debated. We compare predictions of six models to surface activity of strongly surface active aerosol and find significant differences between the models, especially with large fractions of surfactant in the dry particles.
Haiyan Li, Thomas Golin Almeida, Yuanyuan Luo, Jian Zhao, Brett B. Palm, Christopher D. Daub, Wei Huang, Claudia Mohr, Jordan E. Krechmer, Theo Kurtén, and Mikael Ehn
Atmos. Meas. Tech., 15, 1811–1827,Short summary
This work evaluated the potential for PTR-based mass spectrometers to detect ROOR and ROOH peroxides both experimentally and through computations. Laboratory experiments using a Vocus PTR observed only noisy signals of potential dimers during α-pinene ozonolysis and a few small signals of dimeric compounds during cyclohexene ozonolysis. Quantum chemical calculations for model ROOR and ROOH systems showed that most of these peroxides should fragment partially following protonation.
Sampo Vepsäläinen, Silvia M. Calderón, Jussi Malila, and Nønne L. Prisle
Atmos. Chem. Phys., 22, 2669–2687,Short summary
Atmospheric aerosols act as seeds for cloud formation. Many aerosols contain surface active material that accumulates at the surface of growing droplets. This can affect cloud droplet activation, but the broad significance of the effect and the best way to model it are still debated. We compare predictions of six different model approaches to surface activity of organic aerosols and find significant differences between the models, especially with large fractions of organics in the dry particles.
Nønne L. Prisle
Atmos. Chem. Phys., 21, 16387–16411,Short summary
A mass-based Gibbs adsorption model is presented to enable predictive Köhler calculations of droplet growth and activation with considerations of surface partitioning, surface tension, and non-ideal water activity for chemically complex and unresolved surface active aerosol mixtures, including actual atmospheric samples. The model is used to calculate cloud condensation nuclei (CCN) activity of aerosol particles comprising strongly surface-active model atmospheric humic-like substances (HULIS).
Emma Lumiaro, Milica Todorović, Theo Kurten, Hanna Vehkamäki, and Patrick Rinke
Atmos. Chem. Phys., 21, 13227–13246,Short summary
The study of climate change relies on climate models, which require an understanding of aerosol formation. We train a machine-learning model to predict the partitioning coefficients of atmospheric molecules, which govern condensation into aerosols. The model can make instant predictions based on molecular structures with accuracy surpassing that of standard computational methods. This will allow the screening of low-volatility molecules that contribute most to aerosol formation.
Xiaolong Fan, Jing Cai, Chao Yan, Jian Zhao, Yishuo Guo, Chang Li, Kaspar R. Dällenbach, Feixue Zheng, Zhuohui Lin, Biwu Chu, Yonghong Wang, Lubna Dada, Qiaozhi Zha, Wei Du, Jenni Kontkanen, Theo Kurtén, Siddhart Iyer, Joni T. Kujansuu, Tuukka Petäjä, Douglas R. Worsnop, Veli-Matti Kerminen, Yongchun Liu, Federico Bianchi, Yee Jun Tham, Lei Yao, and Markku Kulmala
Atmos. Chem. Phys., 21, 11437–11452,Short summary
We observed significant concentrations of gaseous HBr and HCl throughout the winter and springtime in urban Beijing, China. Our results indicate that gaseous HCl and HBr are most likely originated from anthropogenic emissions such as burning activities, and the gas–aerosol partitioning may play a crucial role in contributing to the gaseous HCl and HBr. These observations suggest that there is an important recycling pathway of halogen species in inland megacities.
Mingyi Wang, Xu-Cheng He, Henning Finkenzeller, Siddharth Iyer, Dexian Chen, Jiali Shen, Mario Simon, Victoria Hofbauer, Jasper Kirkby, Joachim Curtius, Norbert Maier, Theo Kurtén, Douglas R. Worsnop, Markku Kulmala, Matti Rissanen, Rainer Volkamer, Yee Jun Tham, Neil M. Donahue, and Mikko Sipilä
Atmos. Meas. Tech., 14, 4187–4202,Short summary
Atmospheric iodine species are often short-lived with low abundance and have thus been challenging to measure. We show that the bromide chemical ionization mass spectrometry, compatible with both the atmospheric pressure and reduced pressure interfaces, can simultaneously detect various gas-phase iodine species. Combining calibration experiments and quantum chemical calculations, we quantify detection sensitivities to HOI, HIO3, I2, and H2SO4, giving detection limits down to < 106 molec. cm-3.
Jack J. Lin, Kamal Raj R Mundoli, Stella Wang, Esko Kokkonen, Mikko-Heikki Mikkelä, Samuli Urpelainen, and Nønne L. Prisle
Atmos. Chem. Phys., 21, 4709–4727,Short summary
We used surface-sensitive X-ray photoelectron spectroscopy (XPS) to study laboratory-generated nanoparticles of atmospheric interest at 0–16 % relative humidity. XPS gives direct information about changes in the chemical state from the binding energies of probed elements. Our results indicate water adsorption and associated chemical changes at the particle surfaces well below deliquescence, with distinct features for different particle components and implications for atmospheric chemistry.
Anna Shcherbacheva, Tracey Balehowsky, Jakub Kubečka, Tinja Olenius, Tapio Helin, Heikki Haario, Marko Laine, Theo Kurtén, and Hanna Vehkamäki
Atmos. Chem. Phys., 20, 15867–15906,Short summary
Atmospheric new particle formation and cluster growth to aerosol particles is an important field of research, in particular due to the climate change phenomenon. Evaporation rates are very difficult to account for but they are important to explain the formation and growth of particles. Different quantum chemistry (QC) methods produce substantially different values for the evaporation rates. We propose a novel approach for inferring evaporation rates of clusters from available measurements.
Noora Hyttinen, Reyhaneh Heshmatnezhad, Jonas Elm, Theo Kurtén, and Nønne L. Prisle
Atmos. Chem. Phys., 20, 13131–13143,Short summary
We present aqueous solubilities and activity coefficients of mono- and dicarboxylic acids (C1–C6 and C2–C8, respectively) estimated using the COSMOtherm program. In addition, we have calculated effective equilibrium constants of dimerization and hydration of the same acids in the condensed phase. We were also able to improve the agreement between experimental and estimated properties of monocarboxylic acids in aqueous solutions by including clustering reactions in COSMOtherm calculations.
Aikaterini Bougiatioti, Athanasios Nenes, Jack J. Lin, Charles A. Brock, Joost A. de Gouw, Jin Liao, Ann M. Middlebrook, and André Welti
Atmos. Chem. Phys., 20, 12163–12176,Short summary
The number concentration of droplets in clouds in the summertime in the southeastern United States is influenced by aerosol variations but limited by the strong competition for supersaturated water vapor. Concurrent variations in vertical velocity magnify the response of cloud droplet number to aerosol increases by up to a factor of 5. Omitting the covariance of vertical velocity with aerosol number may therefore bias estimates of the cloud albedo effect from aerosols.
Tommaso Zanca, Jakub Kubečka, Evgeni Zapadinsky, Monica Passananti, Theo Kurtén, and Hanna Vehkamäki
Atmos. Meas. Tech., 13, 3581–3593,Short summary
In this paper we quantify (using a statistical model) the probability of decomposition of a representative class of HOM clusters in an APi-TOF mass spectrometer. This is important because it quantifies the systematic error of measurements in a APi-TOF MS due to cluster decomposition. The results (specific for our selected clusters) show that decomposition is negligible, provided their bonding energy is large enough to allow formation in the atmosphere in the first place.
Noora Hyttinen, Jonas Elm, Jussi Malila, Silvia M. Calderón, and Nønne L. Prisle
Atmos. Chem. Phys., 20, 5679–5696,Short summary
Organosulfates have been identified in atmospheric secondary organic aerosol (SOA). The thermodynamic properties of SOA constituents, such as organosulfates, affect the stability and atmospheric impact of the SOA. Here we present estimated solubility, activity, pKa, saturation vapor pressure and Henry's law solubility values for several atmospherically relevant monoterpene- and isoprene-derived organosulfate compounds. These properties can be used, for example, in aerosol process modeling.
Roope Halonen, Evgeni Zapadinsky, Theo Kurtén, Hanna Vehkamäki, and Bernhard Reischl
Atmos. Chem. Phys., 19, 13355–13366,Short summary
The rate of collisions between molecules or clusters is used to determine particle formation in the atmosphere. The basic approach is to treat the colliding particles as noninteracting hard spheres. By using atomistic simulations with a realistic force field and theoretical approaches, we showed that the actual collision rate of two sulfuric acid molecules is more than twice as high as that for hard spheres. The results of this study will improve models of atmospheric particle growth.
Emma L. D'Ambro, Siegfried Schobesberger, Cassandra J. Gaston, Felipe D. Lopez-Hilfiker, Ben H. Lee, Jiumeng Liu, Alla Zelenyuk, David Bell, Christopher D. Cappa, Taylor Helgestad, Ziyue Li, Alex Guenther, Jian Wang, Matthew Wise, Ryan Caylor, Jason D. Surratt, Theran Riedel, Noora Hyttinen, Vili-Taneli Salo, Galib Hasan, Theo Kurtén, John E. Shilling, and Joel A. Thornton
Atmos. Chem. Phys., 19, 11253–11265,Short summary
Isoprene is the most abundantly emitted reactive organic gas globally, and thus it is important to understand its fate and role in aerosol formation and growth. A major product of its oxidation is an epoxydiol, IEPOX, which can be efficiently taken up by acidic aerosol to generate substantial amounts of secondary organic aerosol (SOA). We present chamber experiments exploring the properties of IEPOX SOA and reconcile discrepancies between field, laboratory, and model studies of this process.
Nønne L. Prisle, Jack J. Lin, Sara Purdue, Haisheng Lin, J. Carson Meredith, and Athanasios Nenes
Atmos. Chem. Phys., 19, 4741–4761,Short summary
We measure surface activity and cloud-forming potential of pollenkitt, an organic mixture coating pollen grains. Cloud droplet formation is affected through both surface tension and bulk depletion, with a consistent particle size-dependent signature. We observe nonideal solution effects in pollenkitt mixtures with ammonium sulfate salt. Our results suggest sensitivity of general water interactions, including cloud formation by pollen and their fragments, to both atmospheric humidity and aging.
Michael Boy, Erik S. Thomson, Juan-C. Acosta Navarro, Olafur Arnalds, Ekaterina Batchvarova, Jaana Bäck, Frank Berninger, Merete Bilde, Zoé Brasseur, Pavla Dagsson-Waldhauserova, Dimitri Castarède, Maryam Dalirian, Gerrit de Leeuw, Monika Dragosics, Ella-Maria Duplissy, Jonathan Duplissy, Annica M. L. Ekman, Keyan Fang, Jean-Charles Gallet, Marianne Glasius, Sven-Erik Gryning, Henrik Grythe, Hans-Christen Hansson, Margareta Hansson, Elisabeth Isaksson, Trond Iversen, Ingibjorg Jonsdottir, Ville Kasurinen, Alf Kirkevåg, Atte Korhola, Radovan Krejci, Jon Egill Kristjansson, Hanna K. Lappalainen, Antti Lauri, Matti Leppäranta, Heikki Lihavainen, Risto Makkonen, Andreas Massling, Outi Meinander, E. Douglas Nilsson, Haraldur Olafsson, Jan B. C. Pettersson, Nønne L. Prisle, Ilona Riipinen, Pontus Roldin, Meri Ruppel, Matthew Salter, Maria Sand, Øyvind Seland, Heikki Seppä, Henrik Skov, Joana Soares, Andreas Stohl, Johan Ström, Jonas Svensson, Erik Swietlicki, Ksenia Tabakova, Throstur Thorsteinsson, Aki Virkkula, Gesa A. Weyhenmeyer, Yusheng Wu, Paul Zieger, and Markku Kulmala
Atmos. Chem. Phys., 19, 2015–2061,Short summary
The Nordic Centre of Excellence CRAICC (Cryosphere–Atmosphere Interactions in a Changing Arctic Climate), funded by NordForsk in the years 2011–2016, is the largest joint Nordic research and innovation initiative to date and aimed to strengthen research and innovation regarding climate change issues in the Nordic region. The paper presents an overview of the main scientific topics investigated and provides a state-of-the-art comprehensive summary of what has been achieved in CRAICC.
Theo Kurtén, Noora Hyttinen, Emma Louise D'Ambro, Joel Thornton, and Nønne Lyng Prisle
Atmos. Chem. Phys., 18, 17589–17600,Short summary
We use COSMO-RS to compute saturation vapor pressures for two products of isoprene photo-oxidation and compare the results to measurements. COSMO-RS is an attractive option for calculating properties of molecules, as it is based on quantum mechanics and requires few fitting parameters. However, we show that the default implementation of this method suffers from errors related to both conformational sampling and intramolecular hydrogen bonding. We propose solutions to these problems.
Ulrich K. Krieger, Franziska Siegrist, Claudia Marcolli, Eva U. Emanuelsson, Freya M. Gøbel, Merete Bilde, Aleksandra Marsh, Jonathan P. Reid, Andrew J. Huisman, Ilona Riipinen, Noora Hyttinen, Nanna Myllys, Theo Kurtén, Thomas Bannan, Carl J. Percival, and David Topping
Atmos. Meas. Tech., 11, 49–63,Short summary
Vapor pressures of low-volatility organic molecules at atmospheric temperatures reported in the literature often differ by several orders of magnitude between measurement techniques. These discrepancies exceed the stated uncertainty of each technique, which is generally reported to be smaller than a factor of 2. We determined saturation vapor pressures for the homologous series of polyethylene glycols ranging in vapor pressure at 298 K from 1E−7 Pa to 5E−2 Pa as a reference set.
Emilie Öström, Zhou Putian, Guy Schurgers, Mikhail Mishurov, Niku Kivekäs, Heikki Lihavainen, Mikael Ehn, Matti P. Rissanen, Theo Kurtén, Michael Boy, Erik Swietlicki, and Pontus Roldin
Atmos. Chem. Phys., 17, 8887–8901,Short summary
We used a model to study how biogenic volatile organic compounds (BVOCs) emitted from the boreal forest contribute to the formation and growth of particles in the atmosphere. Some of these particles are important climate forcers, acting as seeds for cloud droplet fomation. We implemented a new gas chemistry mechanism that describes how the BVOCs are oxidized and form low-volatility highly oxidized organic molecules. With the new mechanism we are able to accurately predict the particle growth.
Juan Hong, Mikko Äijälä, Silja A. K. Häme, Liqing Hao, Jonathan Duplissy, Liine M. Heikkinen, Wei Nie, Jyri Mikkilä, Markku Kulmala, Nønne L. Prisle, Annele Virtanen, Mikael Ehn, Pauli Paasonen, Douglas R. Worsnop, Ilona Riipinen, Tuukka Petäjä, and Veli-Matti Kerminen
Atmos. Chem. Phys., 17, 4387–4399,Short summary
Estimates of volatility of secondary organic aerosols was characterized in a boreal forest environment of Hyytiälä, southern Finland. This was done by interpreting field measurements using a volatility tandem differential mobility analyzer (VTDMA) with a kinetic evaporation model and by applying positive matrix factorization (PMF) to high-resolution aerosol mass spectrometer data. About 16 % of the variation can be explained by the linear regression between the results from these two methods.
Hanna K. Lappalainen, Veli-Matti Kerminen, Tuukka Petäjä, Theo Kurten, Aleksander Baklanov, Anatoly Shvidenko, Jaana Bäck, Timo Vihma, Pavel Alekseychik, Meinrat O. Andreae, Stephen R. Arnold, Mikhail Arshinov, Eija Asmi, Boris Belan, Leonid Bobylev, Sergey Chalov, Yafang Cheng, Natalia Chubarova, Gerrit de Leeuw, Aijun Ding, Sergey Dobrolyubov, Sergei Dubtsov, Egor Dyukarev, Nikolai Elansky, Kostas Eleftheriadis, Igor Esau, Nikolay Filatov, Mikhail Flint, Congbin Fu, Olga Glezer, Aleksander Gliko, Martin Heimann, Albert A. M. Holtslag, Urmas Hõrrak, Juha Janhunen, Sirkku Juhola, Leena Järvi, Heikki Järvinen, Anna Kanukhina, Pavel Konstantinov, Vladimir Kotlyakov, Antti-Jussi Kieloaho, Alexander S. Komarov, Joni Kujansuu, Ilmo Kukkonen, Ella-Maria Duplissy, Ari Laaksonen, Tuomas Laurila, Heikki Lihavainen, Alexander Lisitzin, Alexsander Mahura, Alexander Makshtas, Evgeny Mareev, Stephany Mazon, Dmitry Matishov, Vladimir Melnikov, Eugene Mikhailov, Dmitri Moisseev, Robert Nigmatulin, Steffen M. Noe, Anne Ojala, Mari Pihlatie, Olga Popovicheva, Jukka Pumpanen, Tatjana Regerand, Irina Repina, Aleksei Shcherbinin, Vladimir Shevchenko, Mikko Sipilä, Andrey Skorokhod, Dominick V. Spracklen, Hang Su, Dmitry A. Subetto, Junying Sun, Arkady Y. Terzhevik, Yuri Timofeyev, Yuliya Troitskaya, Veli-Pekka Tynkkynen, Viacheslav I. Kharuk, Nina Zaytseva, Jiahua Zhang, Yrjö Viisanen, Timo Vesala, Pertti Hari, Hans Christen Hansson, Gennady G. Matvienko, Nikolai S. Kasimov, Huadong Guo, Valery Bondur, Sergej Zilitinkevich, and Markku Kulmala
Atmos. Chem. Phys., 16, 14421–14461,Short summary
After kick off in 2012, the Pan-Eurasian Experiment (PEEX) program has expanded fast and today the multi-disciplinary research community covers ca. 80 institutes and a network of ca. 500 scientists from Europe, Russia, and China. Here we introduce scientific topics relevant in this context. This is one of the first multi-disciplinary overviews crossing scientific boundaries, from atmospheric sciences to socio-economics and social sciences.
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.
Felipe D. Lopez-Hilfiker, Siddarth Iyer, Claudia Mohr, Ben H. Lee, Emma L. D'Ambro, Theo Kurtén, and Joel A. Thornton
Atmos. Meas. Tech., 9, 1505–1512,Short summary
We present the maximum sensitivity of a TOF-CIMS using the collision limit and iodide adducts. We also present an ion adduct declustering scanning procedure which determines the effective binding energies of the detected ion adducts and therefore their approximate sensitivity. The combination of declustering scanning and the collision limit provides an approximate calibration for many compounds in the mass spectrum which would otherwise be impossible to obtain by traditional methods.
Bjarke Mølgaard, Jarno Vanhatalo, Pasi P. Aalto, Nønne L. Prisle, and Kaarle Hämeri
Atmos. Meas. Tech., 9, 741–751,Short summary
We have improved the reliability of submicron aerosol particle size distributions measured in urban locations. This improvement was obtained by processing the data in a new way and avoiding a problematic assumption of a stationary aerosol during each size distribution measurement.
M. Kulmala, H. K. Lappalainen, T. Petäjä, T. Kurten, V.-M. Kerminen, Y. Viisanen, P. Hari, S. Sorvari, J. Bäck, V. Bondur, N. Kasimov, V. Kotlyakov, G. Matvienko, A. Baklanov, H. D. Guo, A. Ding, H.-C. Hansson, and S. Zilitinkevich
Atmos. Chem. Phys., 15, 13085–13096,Short summary
The Pan-European Experiment (PEEX) is introduced. PEEX is a multidisciplinary, multiscale and multicomponent research, research infrastructure and capacity-building program. This paper outlines the mission, vision and objectives of PEEX and introduces its main components, including the research agenda, research infrastructure, knowledge transfer and potential impacts on society. The paper also summarizes the main scientific questions that PEEX is going to tackle in the future.
Y. Shinozuka, A. D. Clarke, A. Nenes, A. Jefferson, R. Wood, C. S. McNaughton, J. Ström, P. Tunved, J. Redemann, K. L. Thornhill, R. H. Moore, T. L. Lathem, J. J. Lin, and Y. J. Yoon
Atmos. Chem. Phys., 15, 7585–7604,
K. Ruusuvuori, P. Hietala, O. Kupiainen-Määttä, T. Jokinen, H. Junninen, M. Sipilä, T. Kurtén, and H. Vehkamäki
Atmos. Meas. Tech., 8, 2577–2588,Short summary
Ionization reagents suitable for accurate measurements of the atmospheric gas-phase amine vapour concentrations are needed. Based on computational results, acetone is a viable option for use as an ionization reagent in CI-APi-TOF measurements on atmospheric dimethylamine. However, comparison between the computational and experimental results revealed notable discrepancies. Further study is still required before the acetone CI-APi-TOF can be considered a viable option in practice.
T. F. Mentel, M. Springer, M. Ehn, E. Kleist, I. Pullinen, T. Kurtén, M. Rissanen, A. Wahner, and J. Wildt
Atmos. Chem. Phys., 15, 6745–6765,Short summary
We studied a series of cycloalkenes and methyl-substituted alkenes in order to elucidate the structural pre-requisites and chemical pathways to the recently discovered class of highly oxidized molecules ELVOC (Ehn et al., Nature, 2014). ELVOC may totally change the view on (parts of) the mechanism of SOA formation. We present results which support recent observations of H shifts from C-H to peroxy radicals, highlighting the pivotal role of peroxyradicals in organic atmospheric chemistry.
H. Vuollekoski, M. Vogt, V. A. Sinclair, J. Duplissy, H. Järvinen, E.-M. Kyrö, R. Makkonen, T. Petäjä, N. L. Prisle, P. Räisänen, M. Sipilä, J. Ylhäisi, and M. Kulmala
Hydrol. Earth Syst. Sci., 19, 601–613,Short summary
The global potential for collecting usable water from dew on an artificial collector sheet was investigated by utilising 34 years of meteorological reanalysis data as input to a dew formation model. Continental dew formation was found to be frequent and common, but daily yields were mostly below 0.1mm.
M. Sipilä, T. Jokinen, T. Berndt, S. Richters, R. Makkonen, N. M. Donahue, R. L. Mauldin III, T. Kurtén, P. Paasonen, N. Sarnela, M. Ehn, H. Junninen, M. P. Rissanen, J. Thornton, F. Stratmann, H. Herrmann, D. R. Worsnop, M. Kulmala, V.-M. Kerminen, and T. Petäjä
Atmos. Chem. Phys., 14, 12143–12153,
I. K. Ortega, T. Olenius, O. Kupiainen-Määttä, V. Loukonen, T. Kurtén, and H. Vehkamäki
Atmos. Chem. Phys., 14, 7995–8007,
K. Ruusuvuori, T. Kurtén, I. K. Ortega, J. Faust, and H. Vehkamäki
Atmos. Chem. Phys., 13, 10397–10404,
M. Paramonov, P. P. Aalto, A. Asmi, N. Prisle, V.-M. Kerminen, M. Kulmala, and T. Petäjä
Atmos. Chem. Phys., 13, 10285–10301,
N. Bork, T. Kurtén, and H. Vehkamäki
Atmos. Chem. Phys., 13, 3695–3703,
N. L. Prisle, N. Ottosson, G. Öhrwall, J. Söderström, M. Dal Maso, and O. Björneholm
Atmos. Chem. Phys., 12, 12227–12242,
Related subject area
Subject: Aerosols | Research Activity: Laboratory Studies | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)Analysis of insoluble particles in hailstones in ChinaInfluence of acidity on liquid–liquid phase transitions of mixed secondary organic aerosol (SOA) proxy–inorganic aerosol dropletsDeposition freezing, pore condensation freezing and adsorption: three processes, one description?Measurements and calculations of enhanced side- and back-scattering of visible radiation by black carbon aggregatesA Study on the Key Factors Determining the Hygroscopic property of Black CarbonDirect observation for relative-humidity-dependent mixing states of submicron particles containing organic surfactants and inorganic saltsComplex refractive index and single scattering albedo of Icelandic dust in the shortwave part of the spectrumVolatility of aerosol particles from NO3 oxidation of various biogenic organic precursorsInsights into secondary organic aerosol formation from the day- and nighttime oxidation of PAHs and furans in an oxidation flow reactorIs transport of microplastics different from that of mineral dust? Results from idealized wind tunnel studiesSaturation vapor pressure characterization of selected low-volatility organic compounds using a residence time chamberJet aircraft lubrication oil droplets as contrail ice-forming particlesInfluence of the previous North Atlantic Oscillation (NAO) on the spring dust aerosols over North ChinaHUB: a method to model and extract the distribution of ice nucleation temperatures from drop-freezing experimentsSize-dependent hygroscopicity of levoglucosan and D-glucose aerosol nanoparticlesTechnical note: Sublimation of frozen CsCl solutions in an environmental scanning electron microscope (ESEM) – determining the number and size of salt particles relevant to sea salt aerosolsMicrophysics of liquid water in sub-10 nm ultrafine aerosol particlesComparing the ice nucleation properties of the kaolin minerals kaolinite and halloysitePhysicochemical properties of charcoal aerosols derived from biomass pyrolysis affect their ice-nucleating abilities at cirrus and mixed-phase cloud conditionsReconsideration of surface tension and phase state effects on cloud condensation nuclei activity based on the atomic force microscopy measurementHygroscopicity and CCN potential of DMS-derived aerosol particlesHybrid water adsorption and solubility partitioning for aerosol hygroscopicity and droplet growthExperimental development of a lake spray source function and its model implementation for Great Lakes surface emissionsThe effectiveness of the coagulation sink of 3–10 nm atmospheric particlesWhat caused the interdecadal shift in the El Niño–Southern Oscillation (ENSO) impact on dust mass concentration over northwestern South Asia?Measurement report: An exploratory study of fluorescence and cloud condensation nuclei activity of urban aerosols in San Juan, Puerto RicoViscosity and physical state of sucrose mixed with ammonium sulfate dropletsDistribution and stable carbon isotopic composition of dicarboxylic acids, ketocarboxylic acids and α-dicarbonyls in fresh and aged biomass burning aerosolsTime dependence of heterogeneous ice nucleation by ambient aerosols: laboratory observations and a formulation for modelsLaboratory studies of ice nucleation onto bare and internally mixed soot–sulfuric acid particlesEnhanced soot particle ice nucleation ability induced by aggregate compaction and densificationOpinion: Insights into updating Ambient Air Quality Directive 2008/50/ECOn the evolution of sub- and super-saturated water uptake of secondary organic aerosol in chamber experiments from mixed precursorsHygroscopicity of organic compounds as a function of organic functionality, water solubility, molecular weight, and oxidation levelParticle emissions from a modern heavy-duty diesel engine as ice nuclei in immersion freezing mode: a laboratory study on fossil and renewable fuelsComparison of saturation vapor pressures of α-pinene + O3 oxidation products derived from COSMO-RS computations and thermal desorption experimentsPhysical and chemical properties of black carbon and organic matter from different combustion and photochemical sources using aerodynamic aerosol classificationTechnical note: Pyrolysis principles explain time-resolved organic aerosol release from biomass burningThe effect of (NH4)2SO4 on the freezing properties of non-mineral dust ice-nucleating substances of atmospheric relevanceHeterogeneous ice nucleation ability of aerosol particles generated from Arctic sea surface microlayer and surface seawater samples at cirrus temperaturesAerosol formation and growth rates from chamber experiments using Kalman smoothingPhase state of secondary organic aerosol in chamber photo-oxidation of mixed precursorsIce nucleation on surrogates of boreal forest SOA particles: effect of water content and oxidative ageViscosity and phase state of aerosol particles consisting of sucrose mixed with inorganic saltsObservations on hygroscopic growth and phase transitions of mixed 1, 2, 6-hexanetriol ∕ (NH4)2SO4 particles: investigation of the liquid–liquid phase separation (LLPS) dynamic process and mechanism and secondary LLPS during the dehumidificationBoundary layer structure characteristics under objective classification of persistent pollution weather types in the Beijing areaProperties and emission factors of cloud condensation nuclei from biomass cookstoves – observations of a strong dependency on potassium content in the fuelMeasurement report: Effects of NOx and seed aerosol on highly oxygenated organic molecules (HOMs) from cyclohexene ozonolysisInteractions of organosulfates with water vapor under sub- and supersaturated conditionsLaboratory study of the collection efficiency of submicron aerosol particles by cloud droplets – Part I: Influence of relative humidity
Haifan Zhang, Xiangyu Lin, Qinghong Zhang, Kai Bi, Chan-Pang Ng, Yangze Ren, Huiwen Xue, Li Chen, and Zhuolin Chang
Atmos. Chem. Phys., 23, 13957–13971,Short summary
This work is the first study to simultaneously analyze the number concentrations and species of insoluble particles in hailstones. The size distribution of insoluble particles for each species vary greatly in different hailstorms but little in shells. Two classic size distribution modes of organics and dust were fitted for the description of insoluble particles in deep convection. Combining this study with future experiments will lead to refinement of weather and climate models.
Yueling Chen, Xiangyu Pei, Huichao Liu, Yikan Meng, Zhengning Xu, Fei Zhang, Chun Xiong, Thomas C. Preston, and Zhibin Wang
Atmos. Chem. Phys., 23, 10255–10265,Short summary
The impact of acidity on the phase transition behavior of levitated aerosol particles was examined. Our results revealed that lower acidity decreases the separation relative humidity of aerosol droplets mixed with ammonium sulfate and secondary organic aerosol proxy. Our research suggests that in real atmospheric conditions, with the high acidity found in many ambient aerosol particles, droplets encounter heightened impediments to phase separation and tend to display a homogeneous structure.
Mária Lbadaoui-Darvas, Ari Laaksonen, and Athanasios Nenes
Atmos. Chem. Phys., 23, 10057–10074,Short summary
Heterogeneous ice nucleation is the main ice formation mechanism in clouds. The mechanism of different freezing modes is to date unknown, which results in large model biases. Experiments do not allow for direct observation of ice nucleation at its native resolution. This work uses first principles molecular simulations to determine the mechanism of the least-understood ice nucleation mode and link it to adsorption through a novel modeling framework that unites ice and droplet formation.
Carynelisa Haspel, Cuiqi Zhang, Martin J. Wolf, Daniel J. Cziczo, and Maor Sela
Atmos. Chem. Phys., 23, 10091–10115,Short summary
Small particles, commonly termed aerosols, can be found throughout the atmosphere and come from both natural and anthropogenic sources. One important type of aerosol is black carbon (BC). In this study, we conducted laboratory measurements of light scattering by particles meant to mimic atmospheric BC and compared them to calculations of scattering. We find that it is likely that calculations underpredict the scattering by BC particles of certain polarizations of light in certain directions.
Zhanyu Su, Lanxiadi Chen, Yuan Liu, Peng Zhang, Tianzeng Chen, Biwu Chu, Mingjin Tang, Qingxin Ma, and Hong He
In this study, different Black carbon (BC) particles were analyzed to better understand their behavior. It was discovered that water-soluble substances in BC facilitate water adsorption at low humidity, while increasing the number of water layers at high humidity. BC from organic fuels, exhibits hygroscopicity influenced by organic carbon and microstructure. Additionally, the presence of sulfate ions due to the oxidation of SO2 enhances BC's hygroscopicity.
Chun Xiong, Binyu Kuang, Fei Zhang, Xiangyu Pei, Zhengning Xu, and Zhibin Wang
Atmos. Chem. Phys., 23, 8979–8991,Short summary
In hydration, an apparent water diffusion hindrance by an organic surfactant shell was confirmed, raising the inorganic deliquescence relative humidity (RH) to a nearly saturated condition. In dehydration, phase separations were observed for inorganic surfactant systems, showing a strong dependence on the organic molecular oxygen-to-carbon ratio. Our results could improve fundamental knowledge about aerosol mixing states and decrease uncertainty in model estimations of global radiative effects.
Clarissa Baldo, Paola Formenti, Claudia Di Biagio, Gongda Lu, Congbo Song, Mathieu Cazaunau, Edouard Pangui, Jean-Francois Doussin, Pavla Dagsson-Waldhauserova, Olafur Arnalds, David Beddows, A. Robert MacKenzie, and Zongbo Shi
Atmos. Chem. Phys., 23, 7975–8000,Short summary
This paper presents new shortwave spectral complex refractive index and single scattering albedo data for Icelandic dust. Our results show that the imaginary part of the complex refractive index of Icelandic dust is at the upper end of the range of low-latitude dust. Furthermore, we observed that Icelandic dust is more absorbing towards the near-infrared, which we attribute to its high magnetite content. These findings are important for modeling dust aerosol radiative effects in the Arctic.
Emelie L. Graham, Cheng Wu, David M. Bell, Amelie Bertrand, Sophie L. Haslett, Urs Baltensperger, Imad El Haddad, Radovan Krejci, Ilona Riipinen, and Claudia Mohr
Atmos. Chem. Phys., 23, 7347–7362,Short summary
The volatility of an aerosol particle is an important parameter for describing its atmospheric lifetime. We studied the volatility of secondary organic aerosols from nitrate-initiated oxidation of three biogenic precursors with experimental methods and model simulations. We saw higher volatility than for the corresponding ozone system, and our simulations produced variable results with different parameterizations which warrant a re-evaluation of the treatment of the nitrate functional group.
Abd El Rahman El Mais, Barbara D'Anna, Luka Drinovec, Andrew Lambe, Zhe Peng, Jean-Eudes Petit, Olivier Favez, Selim Ait-Aissa, and Alexandre Albinet
Polycyclic aromatic hydrocarbons (PAHS) and furans are key precursors of secondary organic aerosols (SOA) related to biomass burning emissions. We evaluated and compared the formation yields, physical and light absorption properties of laboratory-generated SOA from the oxidation of such compounds for both, daytime and nighttime reactivities. The results illustrate that PAHs are large SOA precursors and may contribute significantly to the biomass burning Brown Carbon (BrC) in the atmosphere.
Eike Maximilian Esders, Sebastian Sittl, Inka Krammel, Wolfgang Babel, Georg Papastavrou, and Christoph Karl Thomas
We asked, Is the transport of plastic dust via air different from mineral dust? We observed plastic and mineral particles in a wind tunnel and measured at what wind speeds the particles start to move. The results show that plastic and mineral particles smaller than 70 µm behave similarly. For bigger particles, plastic particles move more easily, as they weigh less. We conclude that it is no surprise, that like mineral dust, plastic dust is found all around the globe, transported via air.
Zijun Li, Noora Hyttinen, Miika Vainikka, Olli-Pekka Tikkasalo, Siegfried Schobesberger, and Taina Yli-Juuti
Atmos. Chem. Phys., 23, 6863–6877,Short summary
The saturation vapor pressure (psat) of low-volatility organic compounds (LVOCs) governs their partitioning between the gas and particle phases. To estimate the psat of selected LVOCs, we performed particle evaporation measurements in a residence time chamber at a temperature setting relevant to atmospheric aerosol formation and conducted state-of-the-art computational calculations. We found good agreement between the experimentally measured and model-estimated psat values for most LVOCs.
Joel Ponsonby, Leon King, Benjamin Murray, and Marc Stettler
Aerosol emissions from aircraft engines contribute to the formation of contrails, which have a climate impact as important as that of aviation’s CO2 emissions. For the first time, we experimentally investigate the freezing behaviour of water droplets formed on jet lubrication oil aerosol. We show that they can activate to form water droplets and discuss their potential impact on contrail formation. Our study has implications for contrails produce by future aircraft engine and fuel technologies.
Yan Li, Falei Xu, Juan Feng, Mengying Du, Wenjun Song, Chao Li, and Wenjing Zhao
Atmos. Chem. Phys., 23, 6021–6042,Short summary
There is a significantly negative relationship between boreal winter North Atlantic Oscillation (NAO) and dust aerosols (DAs) in the eastern part of China (30–40°N, 105–120°E), which is not a DA source area but is severely affected by the dust events (DEs). Under the effect of the NAO negative phase, main atmospheric circulation during the DEs is characterized by variation of the transient eddy flux. The work is of reference value to the prediction of DEs and the understanding of their causes.
Ingrid de Almeida Ribeiro, Konrad Meister, and Valeria Molinero
Atmos. Chem. Phys., 23, 5623–5639,Short summary
Ice formation is a key atmospheric process facilitated by a wide range of aerosols. We present a method to model and interpret ice nucleation experiments and extract the distribution of the potency of nucleation sites. We use the method to optimize the conditions of laboratory sampling and extract distributions of ice nucleation temperatures from bacteria, fungi, and pollen. These reveal unforeseen subpopulations of nuclei in these systems and how they respond to changes in their environment.
Ting Lei, Hang Su, Nan Ma, Ulrich Pöschl, Alfred Wiedensohler, and Yafang Cheng
Atmos. Chem. Phys., 23, 4763–4774,Short summary
We investigate the hygroscopic behavior of levoglucosan and D-glucose nanoparticles using a nano-HTDMA. There is a weak size dependence of the hygroscopic growth factor of levoglucosan and D-glucose with diameters down to 20 nm, while a strong size dependence of the hygroscopic growth factor of D-glucose has been clearly observed in the size range 6 to 20 nm. The use of the DKA method leads to good agreement with the hygroscopic growth factor of glucose nanoparticles with diameters down to 6 nm.
Lubica Vetráková, Vilém Neděla, Kamila Závacká, Xin Yang, and Dominik Heger
Atmos. Chem. Phys., 23, 4463–4488,Short summary
Salt aerosols are important to polar atmospheric chemistry and global climate. Therefore, we utilized a unique electron microscope to identify the most suitable conditions for formation of the small salt (CsCl) particles, proxies of the aerosols, from sublimating salty snow. Very low sublimation temperature and low salt concentration are needed for formation of such particles. These observations may help us to better understand polar spring ozone depletion and bromine explosion events.
Xiaohan Li and Ian C. Bourg
Atmos. Chem. Phys., 23, 2525–2556,Short summary
Aerosol particles with sizes smaller than 50 nm impact cloud formation and precipitation. Representation of this effect is hindered by limited understanding of the properties of liquid water in these particles. Our simulations of aerosol particles containing salt or organic compounds reveal that water enters a less cohesive phase at droplet sizes below 4 nm. This effect causes important deviations from theoretical predictions of aerosol properties, including phase state and hygroscopic growth.
Kristian Klumpp, Claudia Marcolli, Ana Alonso-Hellweg, Christopher H. Dreimol, and Thomas Peter
Atmos. Chem. Phys., 23, 1579–1598,Short summary
The prerequisites of a particle surface for efficient ice nucleation are still poorly understood. This study compares the ice nucleation activity of two chemically identical but morphologically different minerals (kaolinite and halloysite). We observe, on average, not only higher ice nucleation activities for halloysite than kaolinite but also higher diversity between individual samples. We identify the particle edges as being the most likely site for ice nucleation.
Fabian Mahrt, Carolin Rösch, Kunfeng Gao, Christopher H. Dreimol, Maria A. Zawadowicz, and Zamin A. Kanji
Atmos. Chem. Phys., 23, 1285–1308,Short summary
Major aerosol types emitted by biomass burning include soot, ash, and charcoal particles. Here, we investigated the ice nucleation activity of 400 nm size-selected particles of two different pyrolyis-derived charcoal types in the mixed phase and cirrus cloud regime. We find that ice nucleation is constrained to cirrus cloud conditions, takes place via pore condensation and freezing, and is largely governed by the particle porosity and mineral content.
Chun Xiong, Xueyan Chen, Xiaolei Ding, Binyu Kuang, Xiangyu Pei, Zhengning Xu, Shikuan Yang, Huan Hu, and Zhibin Wang
Atmos. Chem. Phys., 22, 16123–16135,Short summary
Water surface tension is applied widely in current aerosol–cloud models but could be inappropriate in the presence of atmospheric surfactants. With cloud condensation nuclei (CCN) activity and atomic force microscopy (AFM) measurement results of mixed inorganic salt and dicarboxylic acid particles, we concluded that surface tension reduction and phase state should be carefully considered in aerosol–cloud interactions. Our results could help to decease uncertainties in climate models.
Bernadette Rosati, Sini Isokääntä, Sigurd Christiansen, Mads Mørk Jensen, Shamjad P. Moosakutty, Robin Wollesen de Jonge, Andreas Massling, Marianne Glasius, Jonas Elm, Annele Virtanen, and Merete Bilde
Atmos. Chem. Phys., 22, 13449–13466,Short summary
Sulfate aerosols have a strong influence on climate. Due to the reduction in sulfur-based fossil fuels, natural sulfur emissions play an increasingly important role. Studies investigating the climate relevance of natural sulfur aerosols are scarce. We study the water uptake of such particles in the laboratory, demonstrating a high potential to take up water and form cloud droplets. During atmospheric transit, chemical processing affects the particles’ composition and thus their water uptake.
Kanishk Gohil, Chun-Ning Mao, Dewansh Rastogi, Chao Peng, Mingjin Tang, and Akua Asa-Awuku
Atmos. Chem. Phys., 22, 12769–12787,Short summary
The Hybrid Activity Model (HAM) is a promising new droplet growth model that can be potentially used for the analysis of any type of atmospheric compound. HAM may potentially improve the representation of hygroscopicity of organic aerosols in large-scale global climate models (GCMs), hence reducing the uncertainties in the climate forcing due to the aerosol indirect effect.
Charbel Harb and Hosein Foroutan
Atmos. Chem. Phys., 22, 11759–11779,Short summary
A model representation of lake spray aerosol (LSA) ejection from freshwater breaking waves is crucial for understanding their climatic and public health impacts. We develop an LSA emission parameterization and implement it in an atmospheric model to investigate Great Lakes surface emissions. We find that the same breaking wave is likely to produce fewer aerosols in freshwater than in saltwater and that Great Lakes emissions influence the regional aerosol burden and can reach the cloud layer.
Runlong Cai, Ella Häkkinen, Chao Yan, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 11529–11541,Short summary
The influences of new particle formation on the climate and air quality are governed by particle survival, which has been under debate due to uncertainties in the coagulation sink. Here we measure the coagulation coefficient of sub-10 nm particles and demonstrate that collisions between the freshly nucleated and background particles can effectively lead to coagulation. We further show that the effective coagulation sink is consistent with the new particle formation measured in urban Beijing.
Lamei Shi, Jiahua Zhang, Da Zhang, Jingwen Wang, Xianglei Meng, Yuqin Liu, and Fengmei Yao
Atmos. Chem. Phys., 22, 11255–11274,Short summary
Dust impacts climate and human life. Analyzing the interdecadal change in dust activity and its influence factors is crucial for disaster mitigation. Based on a linear regression method, this study revealed the interdecadal variability of relationships between ENSO and dust over northwestern South Asia from 1982 to 2014 and analyzed the effects of atmospheric factors on this interdecadal variability. The result sheds new light on numerical simulation involving the interdecadal variation of dust.
Bighnaraj Sarangi, Darrel Baumgardner, Benjamin Bolaños-Rosero, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 22, 9647–9661,Short summary
Here, the fluorescent characteristics and cloud-forming efficiency of aerosols at an urban site in Puerto Rico are discussed. The results from this pilot study highlight the capabilities of ultraviolet-induced fluorescence (UV-IF) measurements for characterizing the properties of fluorescing aerosol particles, as they relate to the daily evolution of primary biological aerosol particles. This work has established a database of measurements on which future, longer-term studies will be initiated.
Rani Jeong, Joseph Lilek, Andreas Zuend, Rongshuang Xu, Man Nin Chan, Dohyun Kim, Hi Gyu Moon, and Mijung Song
Atmos. Chem. Phys., 22, 8805–8817,Short summary
In this study, the viscosities of particles of sucrose–H2O, AS–H2O, and sucrose–AS–H2O for OIRs of 4:1, 1:1, and 1:4 for decreasing RH, were quantified by poke-and-flow and bead-mobility techniques at 293 ± 1 K. Based on the viscosity results, the particles of binary and ternary systems ranged from liquid to semisolid, and even the solid state depending on the RH. Moreover, we compared the measured viscosities of ternary systems to the predicted viscosities with excellent agreement.
Minxia Shen, Kin Fai Ho, Wenting Dai, Suixin Liu, Ting Zhang, Qiyuan Wang, Jingjing Meng, Judith C. Chow, John G. Watson, Junji Cao, and Jianjun Li
Atmos. Chem. Phys., 22, 7489–7504,Short summary
Looking at characteristics and δ13C compositions of dicarboxylic acids and related compounds in BB aerosols, we used a combined combustion and aging system to generate fresh and aged aerosols from burning straw. The results showed the emission factors (EFaged) of total diacids of aging experiments were around an order of magnitude higher than EFfresh. This meant that dicarboxylic acids are involved with secondary photochemical processes in the atmosphere rather than primary emissions from BB.
Jonas K. F. Jakobsson, Deepak B. Waman, Vaughan T. J. Phillips, and Thomas Bjerring Kristensen
Atmos. Chem. Phys., 22, 6717–6748,Short summary
Long-lived cold-layer clouds at subzero temperatures are observed to be remarkably persistent in their generation of ice particles and snow precipitation. There is uncertainty about why this is so. This motivates the present lab study to observe the long-term ice-nucleating ability of aerosol samples from the real troposphere. Time dependence of their ice nucleation is observed to be weak in lab experiments exposing the samples to isothermal conditions for up to about 10 h.
Kunfeng Gao, Chong-Wen Zhou, Eszter J. Barthazy Meier, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 5331–5364,Short summary
Incomplete combustion of fossil fuel produces carbonaceous particles called soot. These particles can affect cloud formation by acting as centres for droplet or ice formation. The atmospheric residence time of soot particles is of the order of days to weeks, which can result in them becoming coated by various trace species in the atmosphere such as acids. In this study, we quantify the cirrus cloud-forming ability of soot particles coated with the atmospherically ubiquitous sulfuric acid.
Kunfeng Gao, Franz Friebel, Chong-Wen Zhou, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 4985–5016,Short summary
Soot particles impact cloud formation and radiative properties in the upper atmosphere where aircraft emit carbonaceous particles. We use cloud chambers to mimic the upper atmosphere temperature and humidity to test the influence of the morphology of the soot particles on ice cloud formation. For particles larger than 200 nm, the compacted (densified) samples have a higher affinity for ice crystal formation in the cirrus regime than the fluffy (un-compacted) soot particles of the same sample.
Joel Kuula, Hilkka Timonen, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Tareq Hussein, Pak Lun Fung, Sasu Tarkoma, Mikko Laakso, Erkka Saukko, Aino Ovaska, Markku Kulmala, Ari Karppinen, Lasse Johansson, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 4801–4808,Short summary
Modern and up-to-date policies and air quality management strategies are instrumental in tackling global air pollution. As the European Union is preparing to revise Ambient Air Quality Directive 2008/50/EC, this paper initiates discussion on selected features of the directive that we believe would benefit from a reassessment. The scientific community has the most recent and deepest understanding of air pollution; thus, its contribution is essential.
Yu Wang, Aristeidis Voliotis, Dawei Hu, Yunqi Shao, Mao Du, Ying Chen, Judith Kleinheins, Claudia Marcolli, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 4149–4166,Short summary
Aerosol water uptake plays a key role in atmospheric physicochemical processes. We designed chamber experiments on aerosol water uptake of secondary organic aerosol (SOA) from mixed biogenic and anthropogenic precursors with inorganic seed. Our results highlight this chemical composition influences the reconciliation of the sub- and super-saturated water uptake, providing laboratory evidence for understanding the chemical controls of water uptake of the multi-component aerosol.
Shuang Han, Juan Hong, Qingwei Luo, Hanbing Xu, Haobo Tan, Qiaoqiao Wang, Jiangchuan Tao, Yaqing Zhou, Long Peng, Yao He, Jingnan Shi, Nan Ma, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 3985–4004,Short summary
We present the hygroscopicity of 23 organic species with different physicochemical properties using a hygroscopicity tandem differential mobility analyzer (HTDMA) and compare the results with previous studies. Based on the hygroscopicity parameter κ, the influence of different physicochemical properties that potentially drive hygroscopicity, such as the functionality, water solubility, molar volume, and O : C ratio of organics, are examined separately.
Kimmo Korhonen, Thomas Bjerring Kristensen, John Falk, Vilhelm B. Malmborg, Axel Eriksson, Louise Gren, Maja Novakovic, Sam Shamun, Panu Karjalainen, Lassi Markkula, Joakim Pagels, Birgitta Svenningsson, Martin Tunér, Mika Komppula, Ari Laaksonen, and Annele Virtanen
Atmos. Chem. Phys., 22, 1615–1631,Short summary
We investigated the ice-nucleating abilities of particulate emissions from a modern diesel engine using the portable ice-nuclei counter SPIN, a continuous-flow diffusion chamber instrument. Three different fuels were studied without blending, including fossil diesel and two renewable fuels, testing different emission aftertreatment systems and photochemical aging. We found that the diesel emissions were inefficient ice nuclei, and aging had no or little effect on their ice-nucleating abilities.
Noora Hyttinen, Iida Pullinen, Aki Nissinen, Siegfried Schobesberger, Annele Virtanen, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 1195–1208,Short summary
Accurate saturation vapor pressure estimates of atmospherically relevant organic compounds are critical for modeling secondary organic aerosol (SOA) formation. We investigated vapor pressures of highly oxygenated SOA constituents using state-of-the-art computational and experimental methods. We found a good agreement between low and extremely low vapor pressures estimated using the two methods, and the smallest molecules detected in our experiment were likely products of thermal decomposition.
Dawei Hu, M. Rami Alfarra, Kate Szpek, Justin M. Langridge, Michael I. Cotterell, Claire Belcher, Ian Rule, Zixia Liu, Chenjie Yu, Yunqi Shao, Aristeidis Voliotis, Mao Du, Brett Smith, Greg Smallwood, Prem Lobo, Dantong Liu, Jim M. Haywood, Hugh Coe, and James D. Allan
Atmos. Chem. Phys., 21, 16161–16182,Short 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.
Mariam Fawaz, Anita Avery, Timothy B. Onasch, Leah R. Williams, and Tami C. Bond
Atmos. Chem. Phys., 21, 15605–15618,Short summary
Biomass burning is responsible for 90 % of the emissions of primary organic aerosols to the atmosphere. Emissions from biomass burning sources are considered chaotic. In this work, we developed a controlled experimental approach to understand the controlling factors in emission. Our results showed that emissions are repeatable and deterministic and that emissions from wood can be constrained.
Soleil E. Worthy, Anand Kumar, Yu Xi, Jingwei Yun, Jessie Chen, Cuishan Xu, Victoria E. Irish, Pierre Amato, and Allan K. Bertram
Atmos. Chem. Phys., 21, 14631–14648,Short summary
We studied the effect of (NH4)2SO4 on the immersion freezing of non-mineral dust ice-nucleating substances (INSs) and mineral dusts. (NH4)2SO4 had no effect on the median freezing temperature of 9 of the 10 tested non-mineral dust INSs, slightly decreased that of the other, and increased that of all the mineral dusts. The difference in the response of mineral dust and non-mineral dust INSs to (NH4)2SO4 suggests that they nucleate ice and/or interact with (NH4)2SO4 via different mechanisms.
Robert Wagner, Luisa Ickes, Allan K. Bertram, Nora Els, Elena Gorokhova, Ottmar Möhler, Benjamin J. Murray, Nsikanabasi Silas Umo, and Matthew E. Salter
Atmos. Chem. Phys., 21, 13903–13930,Short 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.
Matthew Ozon, Dominik Stolzenburg, Lubna Dada, Aku Seppänen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 21, 12595–12611,Short summary
Measuring the rate at which aerosol particles are formed is of importance for understanding climate change. We present an analysis method based on Kalman smoothing, which retrieves new particle formation and growth rates from size-distribution measurements. We apply it to atmospheric simulation chamber experiments and show that it agrees well with traditional methods. In addition, it provides reliable uncertainty estimates, and we suggest instrument design optimisation for signal processing.
Yu Wang, Aristeidis Voliotis, Yunqi Shao, Taomou Zong, Xiangxinyue Meng, Mao Du, Dawei Hu, Ying Chen, Zhijun Wu, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 21, 11303–11316,Short summary
Aerosol phase behaviour plays a profound role in atmospheric physicochemical processes. We designed dedicated chamber experiments to study the phase state of secondary organic aerosol from biogenic and anthropogenic mixed precursors. Our results highlight the key role of the organic–inorganic ratio and relative humidity in phase state, but the sources and organic composition are less important. The result provides solid laboratory evidence for understanding aerosol phase in a complex atmosphere.
Ana A. Piedehierro, André Welti, Angela Buchholz, Kimmo Korhonen, Iida Pullinen, Ilkka Summanen, Annele Virtanen, and Ari Laaksonen
Atmos. Chem. Phys., 21, 11069–11078,Short summary
Ice crystals in cirrus clouds contain particles that start ice formation. We study whether particles forming above boreal forests can help in the making of cirrus clouds and if the water content in the particles affects this property. In the laboratory, we made boreal-forest-like particles and cooled and humidified them to measure whether an ice crystal develops. We found that only when dry can these particles form an ice crystal but no better than solution droplets.
Young-Chul Song, Joseph Lilek, Jae Bong Lee, Man Nin Chan, Zhijun Wu, Andreas Zuend, and Mijung Song
Atmos. Chem. Phys., 21, 10215–10228,Short summary
We report viscosity of binary mixtures of organic material / H2O and inorganic salts / H2O, as well as ternary mixtures of organic material / inorganic salts/ H2O, over the atmospheric relative humidity (RH) range. The viscosity measurements indicate that the studied mixed organic–inorganic particles range in phase state from liquid to semi-solid or even solid across the atmospheric RH range at a temperature of 293 K.
Shuaishuai Ma, Zhe Chen, Shufeng Pang, and Yunhong Zhang
Atmos. Chem. Phys., 21, 9705–9717,Short summary
LLPS, efflorescence and deliquescence of aerosol particles can be observed visually and determined quantitatively. Different LLPS mechanisms may dominate successively in mixed organic–inorganic particles. The formation of more concentrated inorganic inclusions may cause secondary LLPS. Furthermore, high inorganic factions may result in an inorganic salt crust enclosing the separated organic phases.
Zhaobin Sun, Xiujuan Zhao, Ziming Li, Guiqian Tang, and Shiguang Miao
Atmos. Chem. Phys., 21, 8863–8882,Short summary
Different weather types will shape significantly different structures of the pollution boundary layer. The findings of this study allow us to understand the inherent difference among heavy pollution boundary layers; in addition, they reveal the formation mechanism of haze pollution from an integrated synoptic-scale and boundary layer structure perspective.
Thomas Bjerring Kristensen, John Falk, Robert Lindgren, Christina Andersen, Vilhelm B. Malmborg, Axel C. Eriksson, Kimmo Korhonen, Ricardo Luis Carvalho, Christoffer Boman, Joakim Pagels, and Birgitta Svenningsson
Atmos. Chem. Phys., 21, 8023–8044,Short summary
Residential biomass combustion is a major anthropogenic source of aerosol particles on regional and global scales. Nevertheless, little is known about those aerosol particles' ability to act as cloud condensation nuclei (CCN) and thus influence cloud properties and climate. Our study shows a strong link between the potassium content in the fuel and emissions of CCN for different stove technologies. Previous studies may have underestimated the anthropogenic climate impact of these emissions.
Meri Räty, Otso Peräkylä, Matthieu Riva, Lauriane Quéléver, Olga Garmash, Matti Rissanen, and Mikael Ehn
Atmos. Chem. Phys., 21, 7357–7372,Short summary
Cyclohexene resembles certain relatively complex compounds in the atmosphere that through oxidation produce vapours that take part in aerosol formation. We studied the highly oxygenated organic molecules (HOMs) formed in cyclohexene ozonolysis, the relationship between their chemical composition and their tendency to condense onto seed aerosol, as well as the effect of NOx pollutants on their signals. Two existing models were also tested for their ability to predict the volatility of the HOMs.
Chao Peng, Patricia N. Razafindrambinina, Kotiba A. Malek, Lanxiadi Chen, Weigang Wang, Ru-Jin Huang, Yuqing Zhang, Xiang Ding, Maofa Ge, Xinming Wang, Akua A. Asa-Awuku, and Mingjin Tang
Atmos. Chem. Phys., 21, 7135–7148,Short summary
Organosulfates are important constituents in tropospheric aerosol particles, but their hygroscopic properties and cloud condensation nuclei activities are not well understood. In our work, three complementary techniques were employed to investigate the interactions of 11 organosulfates with water vapor under sub- and supersaturated conditions.
Alexis Dépée, Pascal Lemaitre, Thomas Gelain, Marie Monier, and Andrea Flossmann
Atmos. Chem. Phys., 21, 6945–6962,Short summary
Present article describe a new In-Cloud Aerosol Scavenging Experiment (In-CASE) that has been conceived to measure the collection efficiency of submicron aerosol particles by cloud droplets. The present article focuses on the influence of phoretic effects on the collection efficiency.
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This study provides insight into hydration of two significant atmospheric compounds, glyoxal and methylglyoxal. Using synchrotron radiation excited X-ray absorption spectroscopy, we confirm that glyoxal is fully hydrated in water, and for the first time, we experimentally detect enol structures in aqueous methylglyoxal. Our results support the contribution of these compounds to secondary organic aerosol formation, known to have a large uncertainty in atmospheric models and climate predictions.
This study provides insight into hydration of two significant atmospheric compounds, glyoxal and...