Articles | Volume 19, issue 14
https://doi.org/10.5194/acp-19-9333-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-19-9333-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Jul 2019
Research article |
| 22 Jul 2019
| 22 Jul 2019
Optimization of process models for determining volatility distribution and viscosity of organic aerosols from isothermal particle evaporation data
Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
Väinö Hämäläinen
Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
Grazia Rovelli
School of Chemistry, University of Bristol, Bristol, BS8 1TS, UK
Antti Lipponen
Atmospheric Research Centre of Eastern Finland, Finnish Meteorological Institute, Kuopio, Finland
Manabu Shiraiwa
Department of Chemistry, University of California, Irvine, CA, USA
Jonathan P. Reid
School of Chemistry, University of Bristol, Bristol, BS8 1TS, UK
Kari E. J. Lehtinen
Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
Atmospheric Research Centre of Eastern Finland, Finnish Meteorological Institute, Kuopio, Finland
Taina Yli-Juuti
Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
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Revised manuscript not accepted
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We present a methodology in Bayesian framework for retrieving atmospheric aerosol optical depth and aerosol type from the pre-computed look-up tables (LUTs). Especially, we consider Bayesian model averaging and uncertainty originating from aerosol model selection and imperfect forward modelling. Our aim is to get more realistic uncertainty estimates. We have applied the methodology to TROPOMI/S5P satellite observations and evaluated the results against ground-based data from the AERONET.
Xiaoxia Shang, Tero Mielonen, Antti Lipponen, Elina Giannakaki, Ari Leskinen, Virginie Buchard, Anton S. Darmenov, Antti Kukkurainen, Antti Arola, Ewan O'Connor, Anne Hirsikko, and Mika Komppula
Atmos. Meas. Tech., 14, 6159–6179, https://doi.org/10.5194/amt-14-6159-2021, https://doi.org/10.5194/amt-14-6159-2021, 2021
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The long-range-transported smoke particles from a Canadian wildfire event were observed with a multi-wavelength Raman polarization lidar and a ceilometer over Kuopio, Finland, in June 2019. The optical properties and the mass concentration estimations were reported for such aged smoke aerosols over northern Europe.
Janne Lampilahti, Hanna E. Manninen, Tuomo Nieminen, Sander Mirme, Mikael Ehn, Iida Pullinen, Katri Leino, Siegfried Schobesberger, Juha Kangasluoma, Jenni Kontkanen, Emma Järvinen, Riikka Väänänen, Taina Yli-Juuti, Radovan Krejci, Katrianne Lehtipalo, Janne Levula, Aadu Mirme, Stefano Decesari, Ralf Tillmann, Douglas R. Worsnop, Franz Rohrer, Astrid Kiendler-Scharr, Tuukka Petäjä, Veli-Matti Kerminen, Thomas F. Mentel, and Markku Kulmala
Atmos. Chem. Phys., 21, 12649–12663, https://doi.org/10.5194/acp-21-12649-2021, https://doi.org/10.5194/acp-21-12649-2021, 2021
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We studied aerosol particle formation and growth in different parts of the planetary boundary layer at two different locations (Po Valley, Italy, and Hyytiälä, Finland). The observations consist of airborne measurements on board an instrumented Zeppelin and a small airplane combined with comprehensive ground-based measurements.
Matthew Ozon, Dominik Stolzenburg, Lubna Dada, Aku Seppänen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 21, 12595–12611, https://doi.org/10.5194/acp-21-12595-2021, https://doi.org/10.5194/acp-21-12595-2021, 2021
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Measuring the rate at which aerosol particles are formed is of importance for understanding climate change. We present an analysis method based on Kalman smoothing, which retrieves new particle formation and growth rates from size-distribution measurements. We apply it to atmospheric simulation chamber experiments and show that it agrees well with traditional methods. In addition, it provides reliable uncertainty estimates, and we suggest instrument design optimisation for signal processing.
Antti Arola, William Wandji Nyamsi, Antti Lipponen, Stelios Kazadzis, Nickolay A. Krotkov, and Johanna Tamminen
Atmos. Meas. Tech., 14, 4947–4957, https://doi.org/10.5194/amt-14-4947-2021, https://doi.org/10.5194/amt-14-4947-2021, 2021
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Methods to estimate surface UV radiation from satellite measurements offer the only means to obtain global coverage, and the development of satellite-based UV algorithms has been ongoing since the early 1990s. One of the main challenges in this development has been how to account for the overall effect of absorption by atmospheric aerosols. One such method was suggested roughly a decade ago, and in this study we propose further improvements for this kind of approach.
Haijie Tong, Fobang Liu, Alexander Filippi, Jake Wilson, Andrea M. Arangio, Yun Zhang, Siyao Yue, Steven Lelieveld, Fangxia Shen, Helmi-Marja K. Keskinen, Jing Li, Haoxuan Chen, Ting Zhang, Thorsten Hoffmann, Pingqing Fu, William H. Brune, Tuukka Petäjä, Markku Kulmala, Maosheng Yao, Thomas Berkemeier, Manabu Shiraiwa, and Ulrich Pöschl
Atmos. Chem. Phys., 21, 10439–10455, https://doi.org/10.5194/acp-21-10439-2021, https://doi.org/10.5194/acp-21-10439-2021, 2021
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We measured radical yields of aqueous PM2.5 extracts and found lower yields at higher concentrations of PM2.5. Abundances of water-soluble transition metals and aromatics in PM2.5 were positively correlated with the relative fraction of •OH but negatively correlated with the relative fraction of C-centered radicals among detected radicals. Composition-dependent reactive species yields may explain differences in the reactivity and health effects of PM2.5 in clean versus polluted air.
Tommaso Galeazzo, Richard Valorso, Ying Li, Marie Camredon, Bernard Aumont, and Manabu Shiraiwa
Atmos. Chem. Phys., 21, 10199–10213, https://doi.org/10.5194/acp-21-10199-2021, https://doi.org/10.5194/acp-21-10199-2021, 2021
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We simulate SOA viscosity with explicit modeling of gas-phase oxidation of isoprene and α-pinene. While the viscosity dependence on relative humidity and mass loadings is captured well by simulations, the model underestimates measured viscosity, indicating missing processes. Kinetic limitations and reduction in mass accommodation may cause an increase in viscosity. The developed model is powerful for investigation of the interplay among gas reactions, chemical composition and phase state.
Matthew Ozon, Aku Seppänen, Jari P. Kaipio, and Kari E. J. Lehtinen
Geosci. Model Dev., 14, 3715–3739, https://doi.org/10.5194/gmd-14-3715-2021, https://doi.org/10.5194/gmd-14-3715-2021, 2021
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Experimental research has provided large amounts of high-quality data on aerosol over the last 2 decades. However, inference of the process rates (e.g., the rates at which particles are generated) is still typically done by simple curve-fitting methods and does not assess the credibility of the estimation. The devised method takes advantage of the Bayesian framework to not only retrieve the state of the observed aerosol system but also to estimate the process rates (e.g., growth rate).
Stephanie Bohlmann, Xiaoxia Shang, Ville Vakkari, Elina Giannakaki, Ari Leskinen, Kari E. J. Lehtinen, Sanna Pätsi, and Mika Komppula
Atmos. Chem. Phys., 21, 7083–7097, https://doi.org/10.5194/acp-21-7083-2021, https://doi.org/10.5194/acp-21-7083-2021, 2021
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Measurements of the multi-wavelength Raman polarization lidar PollyXT and a Halo Photonics StreamLine Doppler lidar have been combined with measurements of pollen type and concentration using a traditional pollen trap at the rural forest site in Vehmasmäki, Finland. Depolarization ratios were measured at three wavelengths. High depolarization ratios were detected during an event with high birch and spruce pollen concentrations and a wavelength dependence of the depolarization ratio was observed.
Jake Wilson, Ulrich Pöschl, Manabu Shiraiwa, and Thomas Berkemeier
Atmos. Chem. Phys., 21, 6175–6198, https://doi.org/10.5194/acp-21-6175-2021, https://doi.org/10.5194/acp-21-6175-2021, 2021
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This work explores the gas–particle partitioning of PAHs on soot with a kinetic model. We show that the equilibration timescale depends on PAH molecular structure, temperature, and particle number concentration. We explore scenarios in which the particulate fraction is perturbed from equilibrium by chemical loss and discuss implications for chemical transport models that assume instantaneous equilibration at each model time step.
Antti Lipponen, Ville Kolehmainen, Pekka Kolmonen, Antti Kukkurainen, Tero Mielonen, Neus Sabater, Larisa Sogacheva, Timo H. Virtanen, and Antti Arola
Atmos. Meas. Tech., 14, 2981–2992, https://doi.org/10.5194/amt-14-2981-2021, https://doi.org/10.5194/amt-14-2981-2021, 2021
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We have developed a new computational method to post-process-correct the satellite aerosol retrievals. The proposed method combines the conventional satellite aerosol retrievals relying on physics-based models and machine learning. The results show significantly improved accuracy in the aerosol data over the operational satellite data products. The correction can be applied to the existing satellite aerosol datasets with no need to fully reprocess the much larger original radiance data.
Antti Ruuskanen, Sami Romakkaniemi, Harri Kokkola, Antti Arola, Santtu Mikkonen, Harri Portin, Annele Virtanen, Kari E. J. Lehtinen, Mika Komppula, and Ari Leskinen
Atmos. Chem. Phys., 21, 1683–1695, https://doi.org/10.5194/acp-21-1683-2021, https://doi.org/10.5194/acp-21-1683-2021, 2021
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The study focuses mainly on cloud-scavenging efficiency of absorbing particulate matter (mainly black carbon) but additionally covers cloud-scavenging efficiency of scattering particles and statistics of cloud condensation nuclei. The main findings give insight into how black carbon is distributed in different particle sizes and the sensitivity to cloud scavenged. The main findings are useful for large-scale modelling for evaluating cloud scavenging.
Manabu Shiraiwa and Ulrich Pöschl
Atmos. Chem. Phys., 21, 1565–1580, https://doi.org/10.5194/acp-21-1565-2021, https://doi.org/10.5194/acp-21-1565-2021, 2021
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Mass accommodation is a crucial process in secondary organic aerosol partitioning that depends on volatility, diffusivity, reactivity, and particle penetration depth of the chemical species involved. For efficient kinetic modeling, we introduce an effective mass accommodation coefficient that accounts for the above influencing factors, can be applied in the common Fuchs–Sutugin approximation, and helps to resolve inconsistencies and shortcomings of earlier experimental and model investigations.
Sabin Kasparoglu, Ying Li, Manabu Shiraiwa, and Markus D. Petters
Atmos. Chem. Phys., 21, 1127–1141, https://doi.org/10.5194/acp-21-1127-2021, https://doi.org/10.5194/acp-21-1127-2021, 2021
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Viscosity is important because it determines the lifetime, impact, and fate of particulate matter. We collected new data to rigorously test a framework that is used to constrain the phase state in global simulations. We find that the framework is accurate as long as appropriate compound specific inputs are available.
Johannes Quaas, Antti Arola, Brian Cairns, Matthew Christensen, Hartwig Deneke, Annica M. L. Ekman, Graham Feingold, Ann Fridlind, Edward Gryspeerdt, Otto Hasekamp, Zhanqing Li, Antti Lipponen, Po-Lun Ma, Johannes Mülmenstädt, Athanasios Nenes, Joyce E. Penner, Daniel Rosenfeld, Roland Schrödner, Kenneth Sinclair, Odran Sourdeval, Philip Stier, Matthias Tesche, Bastiaan van Diedenhoven, and Manfred Wendisch
Atmos. Chem. Phys., 20, 15079–15099, https://doi.org/10.5194/acp-20-15079-2020, https://doi.org/10.5194/acp-20-15079-2020, 2020
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Anthropogenic pollution particles – aerosols – serve as cloud condensation nuclei and thus increase cloud droplet concentration and the clouds' reflection of sunlight (a cooling effect on climate). This Twomey effect is poorly constrained by models and requires satellite data for better quantification. The review summarizes the challenges in properly doing so and outlines avenues for progress towards a better use of aerosol retrievals and better retrievals of droplet concentrations.
Nick Schutgens, Andrew M. Sayer, Andreas Heckel, Christina Hsu, Hiren Jethva, Gerrit de Leeuw, Peter J. T. Leonard, Robert C. Levy, Antti Lipponen, Alexei Lyapustin, Peter North, Thomas Popp, Caroline Poulsen, Virginia Sawyer, Larisa Sogacheva, Gareth Thomas, Omar Torres, Yujie Wang, Stefan Kinne, Michael Schulz, and Philip Stier
Atmos. Chem. Phys., 20, 12431–12457, https://doi.org/10.5194/acp-20-12431-2020, https://doi.org/10.5194/acp-20-12431-2020, 2020
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We intercompare 14 different datasets of satellite observations of aerosol. Such measurements are challenging but also provide the best opportunity to globally observe an atmospheric component strongly related to air pollution and climate change. Our study shows that most datasets perform similarly well on a global scale but that locally errors can be quite different. We develop a technique to estimate satellite errors everywhere, even in the absence of surface reference data.
Santtu Mikkonen, Zoltán Németh, Veronika Varga, Tamás Weidinger, Ville Leinonen, Taina Yli-Juuti, and Imre Salma
Atmos. Chem. Phys., 20, 12247–12263, https://doi.org/10.5194/acp-20-12247-2020, https://doi.org/10.5194/acp-20-12247-2020, 2020
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We determined decennial statistical time trends and diurnal statistical patterns of atmospheric particle number concentrations in various relevant size fractions in the city centre of Budapest in an interval of 2008–2018. The mean overall decrease rate of particles in different size fractions was approximately −5 % scaled for the 10-year measurement interval. The decline can be interpreted as a consequence of the decreased anthropogenic emissions in the city.
Olli-Pekka Tikkanen, Angela Buchholz, Arttu Ylisirniö, Siegfried Schobesberger, Annele Virtanen, and Taina Yli-Juuti
Atmos. Chem. Phys., 20, 10441–10458, https://doi.org/10.5194/acp-20-10441-2020, https://doi.org/10.5194/acp-20-10441-2020, 2020
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We compared the volatility distributions of secondary organic aerosol (SOA) constituents estimated from isothermal evaporation experiments from either particle size change data, by process modelling and global optimization, or from mass spectrometer data with positive matrix factorization analysis. Our results show that, despite the two very different estimation methods, the volatility distributions are comparable if uncertainties are taken into account.
Ying Li, Douglas A. Day, Harald Stark, Jose L. Jimenez, and Manabu Shiraiwa
Atmos. Chem. Phys., 20, 8103–8122, https://doi.org/10.5194/acp-20-8103-2020, https://doi.org/10.5194/acp-20-8103-2020, 2020
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Viscosity is an important property of organic aerosols, but viscosity measurements of ambient organic aerosols are scarce. We developed a method to predict glass transition temperatures using volatility and the atomic oxygen-to-carbon ratio. The method was applied to field observations of volatility distributions to predict viscosity of ambient organic aerosols, yielding consistent results with ambient particle phase-state measurements and global simulations.
William Wandji Nyamsi, Antti Lipponen, Arturo Sanchez-Lorenzo, Martin Wild, and Antti Arola
Atmos. Meas. Tech., 13, 3061–3079, https://doi.org/10.5194/amt-13-3061-2020, https://doi.org/10.5194/amt-13-3061-2020, 2020
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This paper proposes a novel and accurate method for estimating and reconstructing aerosol optical depth from sunshine duration measurements under cloud-free conditions at any place and time since the late 19th century. The method performs very well when compared to AErosol RObotic NETwork measurements and operates an efficient detection of signals from massive volcanic eruptions. Reconstructed long-term aerosol optical depths are in agreement with the dimming/brightening phenomenon.
Arttu Ylisirniö, Angela Buchholz, Claudia Mohr, Zijun Li, Luis Barreira, Andrew Lambe, Celia Faiola, Eetu Kari, Taina Yli-Juuti, Sergey A. Nizkorodov, Douglas R. Worsnop, Annele Virtanen, and Siegfried Schobesberger
Atmos. Chem. Phys., 20, 5629–5644, https://doi.org/10.5194/acp-20-5629-2020, https://doi.org/10.5194/acp-20-5629-2020, 2020
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We studied the chemical composition and volatility of secondary organic aerosol (SOA) particles formed from emissions of Scots pines and compared those results to SOA formed from α-pinene and from a sesquiterpene mixture. We found that SOA formed from single precursors cannot capture the properties of SOA formed from real plant emissions.
Thomas Kühn, Kaarle Kupiainen, Tuuli Miinalainen, Harri Kokkola, Ville-Veikko Paunu, Anton Laakso, Juha Tonttila, Rita Van Dingenen, Kati Kulovesi, Niko Karvosenoja, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 20, 5527–5546, https://doi.org/10.5194/acp-20-5527-2020, https://doi.org/10.5194/acp-20-5527-2020, 2020
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We investigate the effects of black carbon (BC) mitigation on Arctic climate and human health, accounting for the concurrent reduction of other aerosol species. While BC is attributed a net warming effect on climate, most other aerosol species cool the planet. We find that the direct radiative effect of mitigating BC induces cooling, while aerosol–cloud effects offset this cooling and introduce large uncertainties. Furthermore, the reduced aerosol emissions reduce human mortality considerably.
Kimmo Korhonen, Thomas Bjerring Kristensen, John Falk, Robert Lindgren, Christina Andersen, Ricardo Luis Carvalho, Vilhelm Malmborg, Axel Eriksson, Christoffer Boman, Joakim Pagels, Birgitta Svenningsson, Mika Komppula, Kari E. J. Lehtinen, and Annele Virtanen
Atmos. Chem. Phys., 20, 4951–4968, https://doi.org/10.5194/acp-20-4951-2020, https://doi.org/10.5194/acp-20-4951-2020, 2020
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Ice-nucleating abilities of particulate emissions from solid-fuel-burning cookstoves were studied using a portable ice nuclei counter in an extensive laboratory experiment campaign. We found that even small changes in combustion conditions may affect the ice-nucleating ability of the emissions significantly. Also six different physico-chemical properties of the emissions were studied, but no clear correlation to their ice-nucleating ability was found.
Andrew M. Sayer, Yves Govaerts, Pekka Kolmonen, Antti Lipponen, Marta Luffarelli, Tero Mielonen, Falguni Patadia, Thomas Popp, Adam C. Povey, Kerstin Stebel, and Marcin L. Witek
Atmos. Meas. Tech., 13, 373–404, https://doi.org/10.5194/amt-13-373-2020, https://doi.org/10.5194/amt-13-373-2020, 2020
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Satellite measurements of the Earth are routinely processed to estimate useful quantities; one example is the amount of atmospheric aerosols (which are particles such as mineral dust, smoke, volcanic ash, or sea spray). As with all measurements and inferred quantities, there is some degree of uncertainty in this process.
There are various methods to estimate these uncertainties. A related question is the following: how reliable are these estimates? This paper presents a method to assess them.
Santtu Mikkonen, Mikko R. A. Pitkänen, Tuomo Nieminen, Antti Lipponen, Sini Isokääntä, Antti Arola, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 19, 12531–12543, https://doi.org/10.5194/acp-19-12531-2019, https://doi.org/10.5194/acp-19-12531-2019, 2019
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Atmospheric measurement data never come without measurement error. Too often, these errors are neglected when researchers make inferences from their data. We applied multiple line-fitting methods to simulated data mimicking two central variables in aerosol research. Our results show that an ordinary least squares fit, typically used to describe relationships, underestimates the slope of the fit and that methods taking the measurement uncertainty into account performed significantly better.
Mijung Song, Adrian M. Maclean, Yuanzhou Huang, Natalie R. Smith, Sandra L. Blair, Julia Laskin, Alexander Laskin, Wing-Sy Wong DeRieux, Ying Li, Manabu Shiraiwa, Sergey A. Nizkorodov, and Allan K. Bertram
Atmos. Chem. Phys., 19, 12515–12529, https://doi.org/10.5194/acp-19-12515-2019, https://doi.org/10.5194/acp-19-12515-2019, 2019
Kelly L. Pereira, Grazia Rovelli, Young C. Song, Alfred W. Mayhew, Jonathan P. Reid, and Jacqueline F. Hamilton
Atmos. Meas. Tech., 12, 4519–4541, https://doi.org/10.5194/amt-12-4519-2019, https://doi.org/10.5194/amt-12-4519-2019, 2019
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We present the design and operation of a newly built continuous-flow reactor (CFR), which can be used as a tool to gain considerable insights into the composition and physical state of secondary organic aerosol (SOA). The CFR was used to generate large quantities of SOA mass, allowing the use of highly accurate techniques that are not usually accessible. We demonstrate how this unique approach can be used to investigate the relationship between SOA formation and physiochemical properties.
Erin Evoy, Adrian M. Maclean, Grazia Rovelli, Ying Li, Alexandra P. Tsimpidi, Vlassis A. Karydis, Saeid Kamal, Jos Lelieveld, Manabu Shiraiwa, Jonathan P. Reid, and Allan K. Bertram
Atmos. Chem. Phys., 19, 10073–10085, https://doi.org/10.5194/acp-19-10073-2019, https://doi.org/10.5194/acp-19-10073-2019, 2019
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We measured the diffusion rates of organic molecules in a number of proxies for secondary organic aerosol (SOA) and compared measured diffusion with predictions from two relations: the Stokes–Einstein relation and a fractional Stokes–Einstein relation. The fractional relation does a better job of predicting diffusion rates in this case. Output from an atmospheric model shows that mixing times predicted using the two relations differ by up to 1 order of magnitude at an altitude of ~ 3 km.
Ying Li and Manabu Shiraiwa
Atmos. Chem. Phys., 19, 5959–5971, https://doi.org/10.5194/acp-19-5959-2019, https://doi.org/10.5194/acp-19-5959-2019, 2019
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Timescales for secondary organic aerosols (SOA) to reach equilibrium were estimated under various temperatures and relative humidities. Equilibration timescales in free troposphere can be longer than hours or days, even at moderate or relatively high relative humidities. These results provide critical insights into thermodynamic or kinetic treatments of SOA partitioning for accurate predictions of gas- and particle-phase concentrations of semi-volatile compounds in chemical transport models.
Angela Buchholz, Andrew T. Lambe, Arttu Ylisirniö, Zijun Li, Olli-Pekka Tikkanen, Celia Faiola, Eetu Kari, Liqing Hao, Olli Luoma, Wei Huang, Claudia Mohr, Douglas R. Worsnop, Sergey A. Nizkorodov, Taina Yli-Juuti, Siegfried Schobesberger, and Annele Virtanen
Atmos. Chem. Phys., 19, 4061–4073, https://doi.org/10.5194/acp-19-4061-2019, https://doi.org/10.5194/acp-19-4061-2019, 2019
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We studied the evaporation of α-pinene secondary organic aerosol particles in clean air to derive their volatility from the observed size changes. We found that the particles became more resilient to evaporation with increased oxidative age, possibly increasing their lifetime in the atmosphere. Also, increased relative humidity increased the particle evaporation. Mass spectrometry measurements of the particles at different stages of evaporation revealed some water-induced composition changes.
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, https://doi.org/10.5194/amt-12-1429-2019, https://doi.org/10.5194/amt-12-1429-2019, 2019
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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.
Liqing Hao, Olga Garmash, Mikael Ehn, Pasi Miettinen, Paola Massoli, Santtu Mikkonen, Tuija Jokinen, Pontus Roldin, Pasi Aalto, Taina Yli-Juuti, Jorma Joutsensaari, Tuukka Petäjä, Markku Kulmala, Kari E. J. Lehtinen, Douglas R. Worsnop, and Annele Virtanen
Atmos. Chem. Phys., 18, 17705–17716, https://doi.org/10.5194/acp-18-17705-2018, https://doi.org/10.5194/acp-18-17705-2018, 2018
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An aerosol mass spectrometer was used to characterize aerosol chemical composition during new particle formation periods. The time profiles of mass concentrations and chemical composition of observed aerosol particles are subjected to joint effects of boundary layer dilution, atmospheric chemistry and aerosol mixing in different boundary layers. During the nighttime, the increase in organic aerosol mass correlated well with the increase in condensed highly oxygenated organic molecules' mass.
Harri Kokkola, Thomas Kühn, Anton Laakso, Tommi Bergman, Kari E. J. Lehtinen, Tero Mielonen, Antti Arola, Scarlet Stadtler, Hannele Korhonen, Sylvaine Ferrachat, Ulrike Lohmann, David Neubauer, Ina Tegen, Colombe Siegenthaler-Le Drian, Martin G. Schultz, Isabelle Bey, Philip Stier, Nikos Daskalakis, Colette L. Heald, and Sami Romakkaniemi
Geosci. Model Dev., 11, 3833–3863, https://doi.org/10.5194/gmd-11-3833-2018, https://doi.org/10.5194/gmd-11-3833-2018, 2018
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In this paper we present a global aerosol–chemistry–climate model with the focus on its representation for atmospheric aerosol particles. In the model, aerosols are simulated using the aerosol module SALSA2.0, which in this paper is compared to satellite, ground, and aircraft-based observations of the properties of atmospheric aerosol. Based on this study, the model simulated aerosol properties compare well with the observations.
Yangxi Chu, Erin Evoy, Saeid Kamal, Young Chul Song, Jonathan P. Reid, Chak K. Chan, and Allan K. Bertram
Atmos. Meas. Tech., 11, 4809–4822, https://doi.org/10.5194/amt-11-4809-2018, https://doi.org/10.5194/amt-11-4809-2018, 2018
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The viscosity of erythritol, a tetrol found in aerosol particles, is highly uncertain. To help resolve this uncertainty, we measured the viscosities of
erythritol–water particles using rectangular-area fluorescence recovery after photobleaching and aerosol optical tweezers techniques. These results
should help improve the understanding of the viscosity of secondary organic aerosol particles. In addition, we present an intercomparison of techniques
for measuring the viscosity of particles.
Jorma Joutsensaari, Matthew Ozon, Tuomo Nieminen, Santtu Mikkonen, Timo Lähivaara, Stefano Decesari, M. Cristina Facchini, Ari Laaksonen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 18, 9597–9615, https://doi.org/10.5194/acp-18-9597-2018, https://doi.org/10.5194/acp-18-9597-2018, 2018
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New particle formation (NPF) in the atmosphere is globally an important source of aerosol particles. NPF events are typically identified and analyzed manually by researchers from particle size distribution data day by day, which is time consuming and might be inconsistent. We have developed an automatic analysis method based on deep learning for NPF event identification. The developed method can be easily utilized to analyze any long-term datasets more accurately and consistently.
Wing-Sy Wong DeRieux, Ying Li, Peng Lin, Julia Laskin, Alexander Laskin, Allan K. Bertram, Sergey A. Nizkorodov, and Manabu Shiraiwa
Atmos. Chem. Phys., 18, 6331–6351, https://doi.org/10.5194/acp-18-6331-2018, https://doi.org/10.5194/acp-18-6331-2018, 2018
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The phase transition of organic particles between glassy and semi-solid states occurs at the glass transition temperature. We developed a method to predict glass transition temperatures and the viscosity of secondary organic aerosols using molecular composition, with consistent results with viscosity measurements. The viscosity of biomass burning particles was also estimated using the chemical composition measured by high-resolution mass spectrometry with two different ionization techniques.
Antti Lipponen, Tero Mielonen, Mikko R. A. Pitkänen, Robert C. Levy, Virginia R. Sawyer, Sami Romakkaniemi, Ville Kolehmainen, and Antti Arola
Atmos. Meas. Tech., 11, 1529–1547, https://doi.org/10.5194/amt-11-1529-2018, https://doi.org/10.5194/amt-11-1529-2018, 2018
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Atmospheric aerosols are small solid or liquid particles suspended in the atmosphere and they have a significant effect on the climate. Satellite data are used to get global estimates of atmospheric aerosols. In this work, a statistics-based Bayesian aerosol retrieval algorithm was developed to improve the accuracy and quantify the uncertainties related to the aerosol estimates. The algorithm is tested with NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data.
Ekaterina Ezhova, Veli-Matti Kerminen, Kari E. J. Lehtinen, and Markku Kulmala
Atmos. Chem. Phys., 18, 2431–2442, https://doi.org/10.5194/acp-18-2431-2018, https://doi.org/10.5194/acp-18-2431-2018, 2018
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A condensation sink (CS) quantifies the rate of uptake of condensing vapours by pre-existing aerosol and can be used as well to quantify losses of monomers/clusters. An analytical solution of the condensation equation valid in a wide range of particle diameters is presented. We describe the dynamics of atmospheric CS, test the formulas against field observations and further use them to develop a simplified model of the coupled dynamics of aerosol and condensing vapours in the atmosphere.
Mallory L. Hinks, Julia Montoya-Aguilera, Lucas Ellison, Peng Lin, Alexander Laskin, Julia Laskin, Manabu Shiraiwa, Donald Dabdub, and Sergey A. Nizkorodov
Atmos. Chem. Phys., 18, 1643–1652, https://doi.org/10.5194/acp-18-1643-2018, https://doi.org/10.5194/acp-18-1643-2018, 2018
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We have observed a strong effect of relative humidity on the composition of particulate matter produced from the oxidation of toluene in clean air. At higher relative humidity, there was a significant reduction in the fraction of high-molecular-weight compounds present in the particles. The amount of particulate matter also decreased at higher relative humidity. The main implication of this study is that water vapor participates in the photooxidation of toluene in a complicated way.
Lukas Pichelstorfer, Dominik Stolzenburg, John Ortega, Thomas Karl, Harri Kokkola, Anton Laakso, Kari E. J. Lehtinen, James N. Smith, Peter H. McMurry, and Paul M. Winkler
Atmos. Chem. Phys., 18, 1307–1323, https://doi.org/10.5194/acp-18-1307-2018, https://doi.org/10.5194/acp-18-1307-2018, 2018
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Quantification of new particle formation as a source of atmospheric aerosol is clearly of importance for climate and health aspects. In our new study we developed two analysis methods that allow retrieval of nanoparticle growth dynamics at much higher precision than it was possible so far. Our results clearly demonstrate that growth rates show much more variation than is currently known and suggest that the Kelvin effect governs growth in the sub-10 nm size range.
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, https://doi.org/10.5194/amt-11-49-2018, https://doi.org/10.5194/amt-11-49-2018, 2018
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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.
Man Mei Chim, Chiu Tung Cheng, James F. Davies, Thomas Berkemeier, Manabu Shiraiwa, Andreas Zuend, and Man Nin Chan
Atmos. Chem. Phys., 17, 14415–14431, https://doi.org/10.5194/acp-17-14415-2017, https://doi.org/10.5194/acp-17-14415-2017, 2017
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In this work, we report that methyl-substituted succinic acid present at or near the surface of aqueous organic droplets can be efficiently oxidized by gas-phase OH radicals. The alkoxy radical chemistry appears to be an important reaction pathway. In addition, our model simulations reveal the relative importance of functionalization and fragmentation processes, alongside volatilization, in the evolution of the particle-phase reaction, which is largely dependent on the extent of oxidation.
Elham Baranizadeh, Tuomo Nieminen, Taina Yli-Juuti, Markku Kulmala, Tuukka Petäjä, Ari Leskinen, Mika Komppula, Ari Laaksonen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 17, 13361–13371, https://doi.org/10.5194/acp-17-13361-2017, https://doi.org/10.5194/acp-17-13361-2017, 2017
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Extrapolation of the particle formation rates from one measured larger size (e.g., 7 nm) to smaller sizes (e.g., 3 nm) based on simplified growth-scavenging dynamics works fairly well to estimate mean daily formation rates, but it fails to predict the time evolution of the particle population. This points to the challenges in predicting atmospheric nucleation rates for locations where the particle growth and loss rates are size- and time-dependent.
Qing Mu, Gerhard Lammel, Christian N. Gencarelli, Ian M. Hedgecock, Ying Chen, Petra Přibylová, Monique Teich, Yuxuan Zhang, Guangjie Zheng, Dominik van Pinxteren, Qiang Zhang, Hartmut Herrmann, Manabu Shiraiwa, Peter Spichtinger, Hang Su, Ulrich Pöschl, and Yafang Cheng
Atmos. Chem. Phys., 17, 12253–12267, https://doi.org/10.5194/acp-17-12253-2017, https://doi.org/10.5194/acp-17-12253-2017, 2017
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Polycyclic aromatic hydrocarbons (PAHs) are hazardous pollutants with the largest emissions in East Asia. The regional WRF-Chem-PAH model has been developed to reflect the state-of-the-art understanding of current PAHs studies with several new or updated features. It is able to reasonably well simulate the concentration levels and particulate mass fractions of PAHs near the sources and at a remote outflow region of East Asia, in high spatial and temporal resolutions.
Michael I. Cotterell, Rose E. Willoughby, Bryan R. Bzdek, Andrew J. Orr-Ewing, and Jonathan P. Reid
Atmos. Chem. Phys., 17, 9837–9851, https://doi.org/10.5194/acp-17-9837-2017, https://doi.org/10.5194/acp-17-9837-2017, 2017
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The optical properties of aerosols are required to analyse measurements of aerosol properties, estimate radiative forcing and interpret remote sensing retrievals. We provide comprehensive data sets of the refractive indices of the most important inorganic aerosol constituents, reporting parameterisations for the wavelength and relative humidity dependencies for each system. We assess the accuracy of this study, made on single trapped particles, against previous less comprehensive data sets.
Thomas Berkemeier, Markus Ammann, Ulrich K. Krieger, Thomas Peter, Peter Spichtinger, Ulrich Pöschl, Manabu Shiraiwa, and Andrew J. Huisman
Atmos. Chem. Phys., 17, 8021–8029, https://doi.org/10.5194/acp-17-8021-2017, https://doi.org/10.5194/acp-17-8021-2017, 2017
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Kinetic process models are efficient tools used to unravel the mechanisms governing chemical and physical transformation in multiphase atmospheric chemistry. However, determination of kinetic parameters such as reaction rate or diffusion coefficients from multiple data sets is often difficult or ambiguous. This study presents a novel optimization algorithm and framework to determine these parameters in an automated fashion and to gain information about parameter uncertainty and uniqueness.
Aleksandra Marsh, Rachael E. H. Miles, Grazia Rovelli, Alexander G. Cowling, Lucy Nandy, Cari S. Dutcher, and Jonathan P. Reid
Atmos. Chem. Phys., 17, 5583–5599, https://doi.org/10.5194/acp-17-5583-2017, https://doi.org/10.5194/acp-17-5583-2017, 2017
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The response of aerosol particles to changes in relative humidity (RH) is dependent on the hygroscopicity of the constituent chemical components. We present accurate measurements of the hygroscopic response of aerosols over a wide range in RH, extending up to the saturation RH. The chemical compounds studied include dicarboxylic acids, amino acids, sugars and polyols. These data provide a comprehensive source of data to help improve functional group activity models of aerosol hygroscopicity.
Grazia Rovelli, Rachael E. H. Miles, Jonathan P. Reid, and Simon L. Clegg
Atmos. Chem. Phys., 17, 4369–4385, https://doi.org/10.5194/acp-17-4369-2017, https://doi.org/10.5194/acp-17-4369-2017, 2017
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The response of airborne particles to relative humidity (RH) in the atmosphere, referred to as their hygroscopicity, is a key property that determines their water content. The hygroscopicity depends on the chemical species that make up the particle. Here, we investigate the growth in particle size and composition that occurs with increasing RH for particles containing a series of amine compounds and sulfuric acid, typical atmospheric components, providing a comprehensive and accurate data set.
Petri Tiitta, Ari Leskinen, Liqing Hao, Pasi Yli-Pirilä, Miika Kortelainen, Julija Grigonyte, Jarkko Tissari, Heikki Lamberg, Anni Hartikainen, Kari Kuuspalo, Aki-Matti Kortelainen, Annele Virtanen, Kari E. J. Lehtinen, Mika Komppula, Simone Pieber, André S. H. Prévôt, Timothy B. Onasch, Douglas R. Worsnop, Hendryk Czech, Ralf Zimmermann, Jorma Jokiniemi, and Olli Sippula
Atmos. Chem. Phys., 16, 13251–13269, https://doi.org/10.5194/acp-16-13251-2016, https://doi.org/10.5194/acp-16-13251-2016, 2016
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Real-time measurements of OA aging and SOA formation from logwood combustion were conducted under dark and UV oxidation. Substantial SOA formation was observed in all experiments, leading to twice the initial OA mass emphasizing the importance of the burning conditions for the aging processes. The results prove that emissions are subject to intensive chemical processing in the atmosphere; e.g. the most of the POA was found to become oxidized after the ozone addition, forming aged POA.
Andrea M. Arangio, Haijie Tong, Joanna Socorro, Ulrich Pöschl, and Manabu Shiraiwa
Atmos. Chem. Phys., 16, 13105–13119, https://doi.org/10.5194/acp-16-13105-2016, https://doi.org/10.5194/acp-16-13105-2016, 2016
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We have quantified environmentally persistent free radicals and reactive oxygen species (ROS) in size-segregated atmospheric aerosol particles. We suggest that ROS were formed by decomposition of secondary organic aerosols interacting with transition metal ions and quinones contained in humic-like substances. The results have significant implications for aqueous-phase and cloud processing of organic aerosols as well as adverse health effects upon respiratory deposition of aerosol particles.
Pascale S. J. Lakey, Thomas Berkemeier, Manuel Krapf, Josef Dommen, Sarah S. Steimer, Lisa K. Whalley, Trevor Ingham, Maria T. Baeza-Romero, Ulrich Pöschl, Manabu Shiraiwa, Markus Ammann, and Dwayne E. Heard
Atmos. Chem. Phys., 16, 13035–13047, https://doi.org/10.5194/acp-16-13035-2016, https://doi.org/10.5194/acp-16-13035-2016, 2016
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Chemical oxidation in the atmosphere removes pollutants and greenhouse gases but generates undesirable products such as secondary organic aerosol. Radicals are key intermediates in oxidation, but how they interact with aerosols is still not well understood. Here we use a laser to measure the loss of radicals onto oxidised aerosols generated in a smog chamber. The loss of radicals was controlled by the thickness or viscosity of the aerosols, confirmed by using sugar aerosols of known thickness.
Natasha Hodas, Andreas Zuend, Katherine Schilling, Thomas Berkemeier, Manabu Shiraiwa, Richard C. Flagan, and John H. Seinfeld
Atmos. Chem. Phys., 16, 12767–12792, https://doi.org/10.5194/acp-16-12767-2016, https://doi.org/10.5194/acp-16-12767-2016, 2016
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Discontinuities in apparent hygroscopicity below and above water saturation have been observed for organic and mixed organic-inorganic aerosol particles in both laboratory studies and in the ambient atmosphere. This work explores the extent to which such discontinuities are influenced by organic component molecular mass and viscosity, non-ideal thermodynamic interactions between aerosol components, and the combination of these factors.
Elham Baranizadeh, Benjamin N. Murphy, Jan Julin, Saeed Falahat, Carly L. Reddington, Antti Arola, Lars Ahlm, Santtu Mikkonen, Christos Fountoukis, David Patoulias, Andreas Minikin, Thomas Hamburger, Ari Laaksonen, Spyros N. Pandis, Hanna Vehkamäki, Kari E. J. Lehtinen, and Ilona Riipinen
Geosci. Model Dev., 9, 2741–2754, https://doi.org/10.5194/gmd-9-2741-2016, https://doi.org/10.5194/gmd-9-2741-2016, 2016
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The molecular mechanisms through which new ultrafine (< 100 nm) aerosol particles are formed in the atmosphere have puzzled the scientific community for decades. In the past few years, however, significant progress has been made in unraveling these processes through laboratory studies and computational efforts. In this work we have implemented these new developments to an air quality model and study the implications of anthropogenically driven particle formation for European air quality.
Olli Väisänen, Antti Ruuskanen, Arttu Ylisirniö, Pasi Miettinen, Harri Portin, Liqing Hao, Ari Leskinen, Mika Komppula, Sami Romakkaniemi, Kari E. J. Lehtinen, and Annele Virtanen
Atmos. Chem. Phys., 16, 10385–10398, https://doi.org/10.5194/acp-16-10385-2016, https://doi.org/10.5194/acp-16-10385-2016, 2016
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In-cloud measurements of aerosol hygroscopicity and cloud droplet activation were conducted in Kuopio, Finland. According to the observations, the less hygroscopic accumulation mode particles were present in the non-activated aerosol, whereas the more hygroscopic particles were scavenged into cloud droplets. The results illustrate the sensitivity of cloud droplet formation to varying chemical composition and highlight the need for proper treatment of anthropogenic aerosols in CCN predictions.
Anna L. Hodshire, Michael J. Lawler, Jun Zhao, John Ortega, Coty Jen, Taina Yli-Juuti, Jared F. Brewer, Jack K. Kodros, Kelley C. Barsanti, Dave R. Hanson, Peter H. McMurry, James N. Smith, and Jeffery R. Pierce
Atmos. Chem. Phys., 16, 9321–9348, https://doi.org/10.5194/acp-16-9321-2016, https://doi.org/10.5194/acp-16-9321-2016, 2016
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Processes that control the growth of newly formed particles are not well understood and limit predictions of aerosol climate impacts. We combine state-of-the-art measurements at a central-US site with a particle-growth model to investigate the species and processes contributing to growth. Observed growth was dominated by organics, sulfate salts, or a mixture of these two. The model qualitatively captures the variability between different days.
Riikka Väänänen, Radovan Krejci, Hanna E. Manninen, Antti Manninen, Janne Lampilahti, Stephany Buenrostro Mazon, Tuomo Nieminen, Taina Yli-Juuti, Jenni Kontkanen, Ari Asmi, Pasi P. Aalto, Petri Keronen, Toivo Pohja, Ewan O'Connor, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-556, https://doi.org/10.5194/acp-2016-556, 2016
Revised manuscript has not been submitted
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A light aircraft was used as a platform to explore the horizontal and vertical variability of the aerosol particles over a boreal forest in Central Finland. This information is needed when data measured at ground level station is extrapolated and parameterized to represent the
conditions of the larger scale. The measurements showed that despite local fluctuations there was a good agreement between the on-ground and airborne measurements inside the planetary boundary layer.
Tero Mielonen, Anca Hienola, Thomas Kühn, Joonas Merikanto, Antti Lipponen, Tommi Bergman, Hannele Korhonen, Pekka Kolmonen, Larisa Sogacheva, Darren Ghent, Antti Arola, Gerrit de Leeuw, and Harri Kokkola
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2016-625, https://doi.org/10.5194/acp-2016-625, 2016
Revised manuscript not accepted
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We studied the temperature dependence of AOD and its radiative effects over the southeastern US. We used spaceborne observations of AOD, LST and tropospheric NO2 with simulations of ECHAM-HAMMOZ. The level of AOD in this region is governed by anthropogenic emissions but the temperature dependency is most likely caused by BVOC emissions. According to the observations and simulations, the regional clear-sky DRE for biogenic aerosols is −0.43 ± 0.88 W/m2/K and −0.86 ± 0.06 W/m2/K, respectively.
Jani Huttunen, Harri Kokkola, Tero Mielonen, Mika Esa Juhani Mononen, Antti Lipponen, Juha Reunanen, Anders Vilhelm Lindfors, Santtu Mikkonen, Kari Erkki Juhani Lehtinen, Natalia Kouremeti, Alkiviadis Bais, Harri Niska, and Antti Arola
Atmos. Chem. Phys., 16, 8181–8191, https://doi.org/10.5194/acp-16-8181-2016, https://doi.org/10.5194/acp-16-8181-2016, 2016
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For a good estimate of the current forcing by anthropogenic aerosols, knowledge in past is needed. One option to lengthen time series is to retrieve aerosol optical depth from solar radiation measurements. We have evaluated several methods for this task. Most of the methods produce aerosol optical depth estimates with a good accuracy. However, machine learning methods seem to be the most applicable not to produce any systematic biases, since they do not need constrain the aerosol properties.
Jenni Kontkanen, Tinja Olenius, Katrianne Lehtipalo, Hanna Vehkamäki, Markku Kulmala, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 16, 5545–5560, https://doi.org/10.5194/acp-16-5545-2016, https://doi.org/10.5194/acp-16-5545-2016, 2016
Ying Li, Ulrich Pöschl, and Manabu Shiraiwa
Atmos. Chem. Phys., 16, 3327–3344, https://doi.org/10.5194/acp-16-3327-2016, https://doi.org/10.5194/acp-16-3327-2016, 2016
Haijie Tong, Andrea M. Arangio, Pascale S. J. Lakey, Thomas Berkemeier, Fobang Liu, Christopher J. Kampf, William H. Brune, Ulrich Pöschl, and Manabu Shiraiwa
Atmos. Chem. Phys., 16, 1761–1771, https://doi.org/10.5194/acp-16-1761-2016, https://doi.org/10.5194/acp-16-1761-2016, 2016
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We provide experimental evidence that terpene and isoprene SOA form substantial amounts of OH radicals upon interaction with liquid water and iron. Our measurements and model results imply that the chemical reactivity of SOA in the atmosphere, particularly in clouds, can be faster than previously thought. Inhalation and deposition of SOA particles in the human respiratory tract may lead to a substantial release of OH radicals in vivo, causing oxidative stress and adverse aerosol health effects.
J. Kim, L. Ahlm, T. Yli-Juuti, M. Lawler, H. Keskinen, J. Tröstl, S. Schobesberger, J. Duplissy, A. Amorim, F. Bianchi, N. M. Donahue, R. C. Flagan, J. Hakala, M. Heinritzi, T. Jokinen, A. Kürten, A. Laaksonen, K. Lehtipalo, P. Miettinen, T. Petäjä, M. P. Rissanen, L. Rondo, K. Sengupta, M. Simon, A. Tomé, C. Williamson, D. Wimmer, P. M. Winkler, S. Ehrhart, P. Ye, J. Kirkby, J. Curtius, U. Baltensperger, M. Kulmala, K. E. J. Lehtinen, J. N. Smith, I. Riipinen, and A. Virtanen
Atmos. Chem. Phys., 16, 293–304, https://doi.org/10.5194/acp-16-293-2016, https://doi.org/10.5194/acp-16-293-2016, 2016
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The hygroscopicity of nucleated nanoparticles was measured in the presence of sulfuric acid, sulfuric acid-dimethylamine, and sulfuric acid-organics derived from α-pinene oxidation during CLOUD7 at CERN in 2012. The hygroscopicity parameter κ decreased with increasing particle size, indicating decreasing acidity of particles.
D. M. Lienhard, A. J. Huisman, U. K. Krieger, Y. Rudich, C. Marcolli, B. P. Luo, D. L. Bones, J. P. Reid, A. T. Lambe, M. R. Canagaratna, P. Davidovits, T. B. Onasch, D. R. Worsnop, S. S. Steimer, T. Koop, and T. Peter
Atmos. Chem. Phys., 15, 13599–13613, https://doi.org/10.5194/acp-15-13599-2015, https://doi.org/10.5194/acp-15-13599-2015, 2015
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New data of water diffusivity in secondary organic aerosol (SOA) material and organic/inorganic model mixtures is presented over an extensive temperature range. Our data suggest that water diffusion in SOA is sufficiently fast so that it is unlikely to have significant consequences on the direct climatic effect under tropospheric conditions. Glass formation in SOA is unlikely to restrict homogeneous ice nucleation.
T. Nieminen, T. Yli-Juuti, H. E. Manninen, T. Petäjä, V.-M. Kerminen, and M. Kulmala
Atmos. Chem. Phys., 15, 12385–12396, https://doi.org/10.5194/acp-15-12385-2015, https://doi.org/10.5194/acp-15-12385-2015, 2015
E. F. Mikhailov, G. N. Mironov, C. Pöhlker, X. Chi, M. L. Krüger, M. Shiraiwa, J.-D. Förster, U. Pöschl, S. S. Vlasenko, T. I. Ryshkevich, M. Weigand, A. L. D. Kilcoyne, and M. O. Andreae
Atmos. Chem. Phys., 15, 8847–8869, https://doi.org/10.5194/acp-15-8847-2015, https://doi.org/10.5194/acp-15-8847-2015, 2015
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Our manuscript describes the hygroscopic properties of accumulation- and coarse-mode aerosol particles sampled at the ZOTTO in central Siberia (61º N, 89º E). The hygroscopic growth measurements were supplemented with chemical analyses of the samples. In addition, the microstructure and chemical composition of aerosol particles were analyzed by x-ray micro-spectroscopy (STXM-NEXAFS) and transmission electron microscopy (TEM).
A. Leskinen, P. Yli-Pirilä, K. Kuuspalo, O. Sippula, P. Jalava, M.-R. Hirvonen, J. Jokiniemi, A. Virtanen, M. Komppula, and K. E. J. Lehtinen
Atmos. Meas. Tech., 8, 2267–2278, https://doi.org/10.5194/amt-8-2267-2015, https://doi.org/10.5194/amt-8-2267-2015, 2015
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A 29 m3 Teflon chamber was characterized and tested with oxidation experiments of toluene. Secondary organic aerosol yields of 12-42 % were obtained. These yields are comparable to those obtained in other laboratories.
M. J. Tang, M. Shiraiwa, U. Pöschl, R. A. Cox, and M. Kalberer
Atmos. Chem. Phys., 15, 5585–5598, https://doi.org/10.5194/acp-15-5585-2015, https://doi.org/10.5194/acp-15-5585-2015, 2015
E. Giannakaki, A. Pfüller, K. Korhonen, T. Mielonen, L. Laakso, V. Vakkari, H. Baars, R. Engelmann, J. P. Beukes, P. G. Van Zyl, M. Josipovic, P. Tiitta, K. Chiloane, S. Piketh, H. Lihavainen, K. E. J. Lehtinen, and M. Komppula
Atmos. Chem. Phys., 15, 5429–5442, https://doi.org/10.5194/acp-15-5429-2015, https://doi.org/10.5194/acp-15-5429-2015, 2015
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In this study we summarize 1 year of Raman lidar observations over South Africa. The analyses of lidar measurements presented here could assist in bridging existing gaps in the knowledge of vertical distribution of aerosols above South Africa, since limited long-term data of this type are available for this region. For the first time, we have been able to cover the full seasonal cycle on geometrical characteristics and optical properties of free tropospheric aerosol layers in the region.
L. Q. Hao, A. Kortelainen, S. Romakkaniemi, H. Portin, A. Jaatinen, A. Leskinen, M. Komppula, P. Miettinen, D. Sueper, A. Pajunoja, J. N. Smith, K. E. J. Lehtinen, D. R. Worsnop, A. Laaksonen, and A. Virtanen
Atmos. Chem. Phys., 14, 13483–13495, https://doi.org/10.5194/acp-14-13483-2014, https://doi.org/10.5194/acp-14-13483-2014, 2014
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Positive matrix factorization (PMF) was applied to the unified high-resolution mass spectra organic species with NO+ and NO2+ ions from the measurement in a mixed region between the boreal forestland and the urban area. The PMF analysis succeeded in separating the mixed spectra into three distinct organic factors and one inorganic factor. The particulate organic nitrate was distinguished by PMF for the first time, with a contribution of one-third of the total nitrate mass.
T. Berkemeier, M. Shiraiwa, U. Pöschl, and T. Koop
Atmos. Chem. Phys., 14, 12513–12531, https://doi.org/10.5194/acp-14-12513-2014, https://doi.org/10.5194/acp-14-12513-2014, 2014
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Glassy organic particles can serve as ice nuclei at low temperatures. We provide a rationale for these findings using a numerical aerosol diffusion model that describes particle phase state and its kinetics during simulated atmospheric updrafts dependent upon composition, size, updraft velocity, temperature and humidity. Our simulations suggest that aerosols from anthropogenic aromatic organics can be particularly relevant for ice cloud formation.
M. Shiraiwa, T. Berkemeier, K. A. Schilling-Fahnestock, J. H. Seinfeld, and U. Pöschl
Atmos. Chem. Phys., 14, 8323–8341, https://doi.org/10.5194/acp-14-8323-2014, https://doi.org/10.5194/acp-14-8323-2014, 2014
C. L. Loza, J. S. Craven, L. D. Yee, M. M. Coggon, R. H. Schwantes, M. Shiraiwa, X. Zhang, K. A. Schilling, N. L. Ng, M. R. Canagaratna, P. J. Ziemann, R. C. Flagan, and J. H. Seinfeld
Atmos. Chem. Phys., 14, 1423–1439, https://doi.org/10.5194/acp-14-1423-2014, https://doi.org/10.5194/acp-14-1423-2014, 2014
T. Yli-Juuti, K. Barsanti, L. Hildebrandt Ruiz, A.-J. Kieloaho, U. Makkonen, T. Petäjä, T. Ruuskanen, M. Kulmala, and I. Riipinen
Atmos. Chem. Phys., 13, 12507–12524, https://doi.org/10.5194/acp-13-12507-2013, https://doi.org/10.5194/acp-13-12507-2013, 2013
S. A. K. Häkkinen, H. E. Manninen, T. Yli-Juuti, J. Merikanto, M. K. Kajos, T. Nieminen, S. D. D'Andrea, A. Asmi, J. R. Pierce, M. Kulmala, and I. Riipinen
Atmos. Chem. Phys., 13, 7665–7682, https://doi.org/10.5194/acp-13-7665-2013, https://doi.org/10.5194/acp-13-7665-2013, 2013
H. Keskinen, A. Virtanen, J. Joutsensaari, G. Tsagkogeorgas, J. Duplissy, S. Schobesberger, M. Gysel, F. Riccobono, J. G. Slowik, F. Bianchi, T. Yli-Juuti, K. Lehtipalo, L. Rondo, M. Breitenlechner, A. Kupc, J. Almeida, A. Amorim, E. M. Dunne, A. J. Downard, S. Ehrhart, A. Franchin, M.K. Kajos, J. Kirkby, A. Kürten, T. Nieminen, V. Makhmutov, S. Mathot, P. Miettinen, A. Onnela, T. Petäjä, A. Praplan, F. D. Santos, S. Schallhart, M. Sipilä, Y. Stozhkov, A. Tomé, P. Vaattovaara, D. Wimmer, A. Prevot, J. Dommen, N. M. Donahue, R.C. Flagan, E. Weingartner, Y. Viisanen, I. Riipinen, A. Hansel, J. Curtius, M. Kulmala, D. R. Worsnop, U. Baltensperger, H. Wex, F. Stratmann, and A. Laaksonen
Atmos. Chem. Phys., 13, 5587–5600, https://doi.org/10.5194/acp-13-5587-2013, https://doi.org/10.5194/acp-13-5587-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Laboratory Studies | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Measurement report: The ice-nucleating activity of lichen sampled in a northern European boreal forest
Viscosity of aqueous ammonium nitrate–organic particles: equilibrium partitioning may be a reasonable assumption for most tropospheric conditions
Determination of the Atmospheric Volatility of Pesticides using Chemical Ionisation Mass Spectrometry
Wind-driven Emission of Marine Ice Nucleating Particles in the Scripps Ocean-Atmosphere Research Simulator (SOARS)
Role of sea spray aerosol at the air–sea interface in transporting aromatic acids to the atmosphere
Modeling the influence of carbon branching structure on secondary organic aerosol formation via multiphase reactions of alkanes
Technical note: Characterization of a single-beam gradient force aerosol optical tweezer for droplet trapping, phase transition monitoring, and morphology studies
Soot aerosols from commercial aviation engines are poor ice-nucleating particles at cirrus cloud temperatures
Contribution of brown carbon to light absorption in emissions of European residential biomass combustion appliances
Measurement report: Water diffusion in single suspended phase-separated aerosols
Water activity and surface tension of aqueous ammonium sulfate and D-glucose aerosol nanoparticles
Jet aircraft lubrication oil droplets as contrail ice-forming particles
A study on the influence of inorganic ions, organic carbon and microstructure on the hygroscopic property of soot
Is transport of microplastics different from mineral particles? Idealized wind tunnel studies on polyethylene microspheres
Insights into secondary organic aerosol formation from the day- and nighttime oxidation of polycyclic aromatic hydrocarbons and furans in an oxidation flow reactor
Analysis of insoluble particles in hailstones in China
Influence of acidity on liquid–liquid phase transitions of mixed secondary organic aerosol (SOA) proxy–inorganic aerosol droplets
Deposition freezing, pore condensation freezing and adsorption: three processes, one description?
Measurements and calculations of enhanced side- and back-scattering of visible radiation by black carbon aggregates
Direct observation for relative-humidity-dependent mixing states of submicron particles containing organic surfactants and inorganic salts
Complex refractive index and single scattering albedo of Icelandic dust in the shortwave part of the spectrum
Volatility of aerosol particles from NO3 oxidation of various biogenic organic precursors
Saturation vapor pressure characterization of selected low-volatility organic compounds using a residence time chamber
Influence of the previous North Atlantic Oscillation (NAO) on the spring dust aerosols over North China
HUB: a method to model and extract the distribution of ice nucleation temperatures from drop-freezing experiments
Size-dependent hygroscopicity of levoglucosan and D-glucose aerosol nanoparticles
Technical note: Sublimation of frozen CsCl solutions in an environmental scanning electron microscope (ESEM) – determining the number and size of salt particles relevant to sea salt aerosols
Microphysics of liquid water in sub-10 nm ultrafine aerosol particles
Comparing the ice nucleation properties of the kaolin minerals kaolinite and halloysite
Physicochemical properties of charcoal aerosols derived from biomass pyrolysis affect their ice-nucleating abilities at cirrus and mixed-phase cloud conditions
Reconsideration of surface tension and phase state effects on cloud condensation nuclei activity based on the atomic force microscopy measurement
Hygroscopicity and CCN potential of DMS-derived aerosol particles
Hybrid water adsorption and solubility partitioning for aerosol hygroscopicity and droplet growth
Experimental development of a lake spray source function and its model implementation for Great Lakes surface emissions
The effectiveness of the coagulation sink of 3–10 nm atmospheric particles
What caused the interdecadal shift in the El Niño–Southern Oscillation (ENSO) impact on dust mass concentration over northwestern South Asia?
Measurement report: An exploratory study of fluorescence and cloud condensation nuclei activity of urban aerosols in San Juan, Puerto Rico
Viscosity and physical state of sucrose mixed with ammonium sulfate droplets
Distribution and stable carbon isotopic composition of dicarboxylic acids, ketocarboxylic acids and α-dicarbonyls in fresh and aged biomass burning aerosols
Time dependence of heterogeneous ice nucleation by ambient aerosols: laboratory observations and a formulation for models
Laboratory studies of ice nucleation onto bare and internally mixed soot–sulfuric acid particles
Enhanced soot particle ice nucleation ability induced by aggregate compaction and densification
Opinion: Insights into updating Ambient Air Quality Directive 2008/50/EC
On the evolution of sub- and super-saturated water uptake of secondary organic aerosol in chamber experiments from mixed precursors
Hygroscopicity of organic compounds as a function of organic functionality, water solubility, molecular weight, and oxidation level
Particle emissions from a modern heavy-duty diesel engine as ice nuclei in immersion freezing mode: a laboratory study on fossil and renewable fuels
Comparison of saturation vapor pressures of α-pinene + O3 oxidation products derived from COSMO-RS computations and thermal desorption experiments
Physical and chemical properties of black carbon and organic matter from different combustion and photochemical sources using aerodynamic aerosol classification
Technical note: Pyrolysis principles explain time-resolved organic aerosol release from biomass burning
The effect of (NH4)2SO4 on the freezing properties of non-mineral dust ice-nucleating substances of atmospheric relevance
Ulrike Proske, Michael P. Adams, Grace C. E. Porter, Mark A. Holden, Jaana Bäck, and Benjamin J. Murray
Atmos. Chem. Phys., 25, 979–995, https://doi.org/10.5194/acp-25-979-2025, https://doi.org/10.5194/acp-25-979-2025, 2025
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Ice-nucleating particles (INPs) aid the freezing of water droplets in clouds and thus modify cloud properties. In a campaign in a Finnish boreal forest, biological INPs were observed, despite many of their potential biological sources being snow-covered. We sampled tree-dwelling lichens that were not covered in snow and tested their ice nucleation ability in the laboratory. We found that the lichen harbours INPs, which may be important in similar snowy environments.
Liviana K. Klein, Allan K. Bertram, Andreas Zuend, Florence Gregson, and Ulrich K. Krieger
Atmos. Chem. Phys., 24, 13341–13359, https://doi.org/10.5194/acp-24-13341-2024, https://doi.org/10.5194/acp-24-13341-2024, 2024
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The viscosity of ammonium nitrate–sucrose–H2O was quantified with three methods ranging from liquid to solid state depending on the relative humidity. Moreover, the corresponding estimated internal aerosol mixing times remained below 1 h for most tropospheric conditions, making equilibrium partitioning a reasonable assumption.
Olivia Mae Jackson, Aristeidis Voliotis, Thomas J. Bannan, Simon P. O'Meara, Gordon McFiggans, Dave Johnson, and Hugh Coe
EGUsphere, https://doi.org/10.5194/egusphere-2024-2380, https://doi.org/10.5194/egusphere-2024-2380, 2024
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The paper details a method of measuring volatility of pesticides using chemical ionisation mass spectrometry (CIMS) to calculate vapour pressure. This was then compared to current literature values and commonly used models. The exact nature of the literature values often remain uncertain due to being hidden in industrial reports. The results show that the method used primarily matches current literature values and any difference can be explained by method differences either in the methodology.
Kathryn A. Moore, Thomas C. J. Hill, Samantha Greeney, Chamika K. Madawala, Raymond J. Leibensperger III, Christopher D. Cappa, M. Dale Stokes, Grant B. Deane, Christopher Lee, Alexei V. Tivanski, Kimberly A. Prather, and Paul J. DeMott
EGUsphere, https://doi.org/10.5194/egusphere-2024-2159, https://doi.org/10.5194/egusphere-2024-2159, 2024
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This article presents results from the first study in a new wind-wave channel at the Scripps Institution of Oceanography. The experiment tested how wind speed over the ocean surface influences production of sea spray particles, which are important for radiative forcing and cloud formation in the atmosphere. We found that particle concentration and chemical composition varied with winds speed, and the changes were driven by changes in wind and wave-breaking rather seawater biology or chemistry.
Yaru Song, Jianlong Li, Narcisse Tsona Tchinda, Kun Li, and Lin Du
Atmos. Chem. Phys., 24, 5847–5862, https://doi.org/10.5194/acp-24-5847-2024, https://doi.org/10.5194/acp-24-5847-2024, 2024
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Aromatic acids can be transferred from seawater to the atmosphere through bubble bursting. The air–sea transfer efficiency of aromatic acids was evaluated by simulating SSA generation with a plunging jet. As a whole, the transfer capacity of aromatic acids may depend on their functional groups and on the bridging effect of cations, as well as their concentration in seawater, as these factors influence the global emission flux of aromatic acids via SSA.
Azad Madhu, Myoseon Jang, and Yujin Jo
Atmos. Chem. Phys., 24, 5585–5602, https://doi.org/10.5194/acp-24-5585-2024, https://doi.org/10.5194/acp-24-5585-2024, 2024
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Secondary organic aerosol (SOA) formation from branched alkanes (BAs) was simulated using the UNIPAR model, which predicted SOA growth via multiphase reactions of hydrocarbons, and compared with chamber data. Product distributions (PDs) of BAs were created by extrapolating PDs of linear alkanes (LAs). To account for methyl branching, an autoxidation reduction factor was applied to PDs. BAs in diesel fuel were shown to produce a higher proportion of SOA compared with LAs.
Xiangyu Pei, Yikan Meng, Yueling Chen, Huichao Liu, Yao Song, Zhengning Xu, Fei Zhang, Thomas C. Preston, and Zhibin Wang
Atmos. Chem. Phys., 24, 5235–5246, https://doi.org/10.5194/acp-24-5235-2024, https://doi.org/10.5194/acp-24-5235-2024, 2024
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An aerosol optical tweezer (AOT) Raman spectroscopy system is developed to capture a single aerosol droplet for phase transition monitoring and morphology studies. Rapid droplet capture is achieved and accurate droplet size and refractive index are retrieved. Results indicate that mixed inorganic/organic droplets are more inclined to form core–shell morphology when RH decreases. The phase transitions of secondary mixed organic aerosol/inorganic droplets vary with their precursors.
Baptiste Testa, Lukas Durdina, Peter A. Alpert, Fabian Mahrt, Christopher H. Dreimol, Jacinta Edebeli, Curdin Spirig, Zachary C. J. Decker, Julien Anet, and Zamin A. Kanji
Atmos. Chem. Phys., 24, 4537–4567, https://doi.org/10.5194/acp-24-4537-2024, https://doi.org/10.5194/acp-24-4537-2024, 2024
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Laboratory experiments on the ice nucleation of real commercial aviation soot particles are investigated for their cirrus cloud formation potential. Our results show that aircraft-emitted soot in the upper troposphere will be poor ice-nucleating particles. Measuring the soot particle morphology and modifying their mixing state allow us to elucidate why these particles are ineffective at forming ice, in contrast to previously used soot surrogates.
Satish Basnet, Anni Hartikainen, Aki Virkkula, Pasi Yli-Pirilä, Miika Kortelainen, Heikki Suhonen, Laura Kilpeläinen, Mika Ihalainen, Sampsa Väätäinen, Juho Louhisalmi, Markus Somero, Jarkko Tissari, Gert Jakobi, Ralf Zimmermann, Antti Kilpeläinen, and Olli Sippula
Atmos. Chem. Phys., 24, 3197–3215, https://doi.org/10.5194/acp-24-3197-2024, https://doi.org/10.5194/acp-24-3197-2024, 2024
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Brown carbon (BrC) emissions were estimated, for residential wood combustion (RWC) from various northern European appliances, utilizing an extensive seven-wavelength aethalometer dataset and thermal–optical carbon analysis. The contribution of BrC370–950 to the absorption of visible light varied between 1 % and 21 %, and was linked with fuel moisture content and combustion efficiency. This study provides important information required for assessing the climate effects of RWC emissions.
Yu-Kai Tong, Zhijun Wu, Min Hu, and Anpei Ye
Atmos. Chem. Phys., 24, 2937–2950, https://doi.org/10.5194/acp-24-2937-2024, https://doi.org/10.5194/acp-24-2937-2024, 2024
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The interplay between aerosols and moisture is one of the most crucial atmospheric processes. However, to date, literature results on the influence of phase separation on water diffusion in aerosols are divergent. This work directly unveiled the water diffusion process in single suspended phase-separated microdroplets and quantitatively analyzed the diffusion rate and extent. The results show that diffusion limitations and certain molecule clusters existed in the phase-separated aerosols.
Eugene F. Mikhailov, Sergey S. Vlasenko, and Alexei A. Kiselev
Atmos. Chem. Phys., 24, 2971–2984, https://doi.org/10.5194/acp-24-2971-2024, https://doi.org/10.5194/acp-24-2971-2024, 2024
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Surface tension and water activity are key thermodynamic parameters determining the impact of atmospheric aerosols on human health and climate. However, these parameters are not well constrained for nanoparticles composed of organic and inorganic compounds. In this study, we determined for the first time the water activity and surface tension of mixed organic/inorganic nanodroplets by applying a differential Köhler analysis (DKA) to hygroscopic growth measurements.
Joel Ponsonby, Leon King, Benjamin J. Murray, and Marc E. J. Stettler
Atmos. Chem. Phys., 24, 2045–2058, https://doi.org/10.5194/acp-24-2045-2024, https://doi.org/10.5194/acp-24-2045-2024, 2024
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Aerosol emissions from aircraft engines contribute to the formation of contrails, which have a climate impact as important as that of aviation’s CO2 emissions. For the first time, we experimentally investigate the freezing behaviour of water droplets formed on jet lubrication oil aerosol. We show that they can activate to form water droplets and discuss their potential impact on contrail formation. Our study has implications for contrails produced by future aircraft engine and fuel technologies.
Zhanyu Su, Lanxiadi Chen, Yuan Liu, Peng Zhang, Tianzeng Chen, Biwu Chu, Mingjin Tang, Qingxin Ma, and Hong He
Atmos. Chem. Phys., 24, 993–1003, https://doi.org/10.5194/acp-24-993-2024, https://doi.org/10.5194/acp-24-993-2024, 2024
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In this study, different soot particles were analyzed to better understand their behavior. It was discovered that water-soluble substances in soot facilitate water adsorption at low humidity while increasing the number of water layers at high humidity. Soot from organic fuels exhibits hygroscopicity influenced by organic carbon and microstructure. Additionally, the presence of sulfate ions due to the oxidation of SO2 enhances soot's hygroscopicity.
Eike Maximilian Esders, Sebastian Sittl, Inka Krammel, Wolfgang Babel, Georg Papastavrou, and Christoph Karl Thomas
Atmos. Chem. Phys., 23, 15835–15851, https://doi.org/10.5194/acp-23-15835-2023, https://doi.org/10.5194/acp-23-15835-2023, 2023
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Do microplastics behave differently from mineral particles when they are exposed to wind? We observed plastic and mineral particles in a wind tunnel and measured at what wind speeds the particles start to move. The results indicate that microplastics start to move at smaller wind speeds as they weigh less and are less sticky. Hence, we think that microplastics also move more easily in the environment.
Abd El Rahman El Mais, Barbara D'Anna, Luka Drinovec, Andrew T. Lambe, Zhe Peng, Jean-Eudes Petit, Olivier Favez, Selim Aït-Aïssa, and Alexandre Albinet
Atmos. Chem. Phys., 23, 15077–15096, https://doi.org/10.5194/acp-23-15077-2023, https://doi.org/10.5194/acp-23-15077-2023, 2023
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Polycyclic aromatic hydrocarbons (PAHS) and furans are key precursors of secondary organic aerosols (SOAs) related to biomass burning emissions. We evaluated and compared the formation yields, and the physical and light absorption properties, of laboratory-generated SOAs from the oxidation of such compounds for both, day- and nighttime reactivities. The results illustrate that PAHs are large SOA precursors and may contribute significantly to the biomass burning brown carbon in the atmosphere.
Haifan Zhang, Xiangyu Lin, Qinghong Zhang, Kai Bi, Chan-Pang Ng, Yangze Ren, Huiwen Xue, Li Chen, and Zhuolin Chang
Atmos. Chem. Phys., 23, 13957–13971, https://doi.org/10.5194/acp-23-13957-2023, https://doi.org/10.5194/acp-23-13957-2023, 2023
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This work is the first study to simultaneously analyze the number concentrations and species of insoluble particles in hailstones. The size distribution of insoluble particles for each species vary greatly in different hailstorms but little in shells. Two classic size distribution modes of organics and dust were fitted for the description of insoluble particles in deep convection. Combining this study with future experiments will lead to refinement of weather and climate models.
Yueling Chen, Xiangyu Pei, Huichao Liu, Yikan Meng, Zhengning Xu, Fei Zhang, Chun Xiong, Thomas C. Preston, and Zhibin Wang
Atmos. Chem. Phys., 23, 10255–10265, https://doi.org/10.5194/acp-23-10255-2023, https://doi.org/10.5194/acp-23-10255-2023, 2023
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The impact of acidity on the phase transition behavior of levitated aerosol particles was examined. Our results revealed that lower acidity decreases the separation relative humidity of aerosol droplets mixed with ammonium sulfate and secondary organic aerosol proxy. Our research suggests that in real atmospheric conditions, with the high acidity found in many ambient aerosol particles, droplets encounter heightened impediments to phase separation and tend to display a homogeneous structure.
Mária Lbadaoui-Darvas, Ari Laaksonen, and Athanasios Nenes
Atmos. Chem. Phys., 23, 10057–10074, https://doi.org/10.5194/acp-23-10057-2023, https://doi.org/10.5194/acp-23-10057-2023, 2023
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Heterogeneous ice nucleation is the main ice formation mechanism in clouds. The mechanism of different freezing modes is to date unknown, which results in large model biases. Experiments do not allow for direct observation of ice nucleation at its native resolution. This work uses first principles molecular simulations to determine the mechanism of the least-understood ice nucleation mode and link it to adsorption through a novel modeling framework that unites ice and droplet formation.
Carynelisa Haspel, Cuiqi Zhang, Martin J. Wolf, Daniel J. Cziczo, and Maor Sela
Atmos. Chem. Phys., 23, 10091–10115, https://doi.org/10.5194/acp-23-10091-2023, https://doi.org/10.5194/acp-23-10091-2023, 2023
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Small particles, commonly termed aerosols, can be found throughout the atmosphere and come from both natural and anthropogenic sources. One important type of aerosol is black carbon (BC). In this study, we conducted laboratory measurements of light scattering by particles meant to mimic atmospheric BC and compared them to calculations of scattering. We find that it is likely that calculations underpredict the scattering by BC particles of certain polarizations of light in certain directions.
Chun Xiong, Binyu Kuang, Fei Zhang, Xiangyu Pei, Zhengning Xu, and Zhibin Wang
Atmos. Chem. Phys., 23, 8979–8991, https://doi.org/10.5194/acp-23-8979-2023, https://doi.org/10.5194/acp-23-8979-2023, 2023
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In hydration, an apparent water diffusion hindrance by an organic surfactant shell was confirmed, raising the inorganic deliquescence relative humidity (RH) to a nearly saturated condition. In dehydration, phase separations were observed for inorganic surfactant systems, showing a strong dependence on the organic molecular
oxygen-to-carbon ratio. Our results could improve fundamental knowledge about aerosol mixing states and decrease uncertainty in model estimations of global radiative effects.
Clarissa Baldo, Paola Formenti, Claudia Di Biagio, Gongda Lu, Congbo Song, Mathieu Cazaunau, Edouard Pangui, Jean-Francois Doussin, Pavla Dagsson-Waldhauserova, Olafur Arnalds, David Beddows, A. Robert MacKenzie, and Zongbo Shi
Atmos. Chem. Phys., 23, 7975–8000, https://doi.org/10.5194/acp-23-7975-2023, https://doi.org/10.5194/acp-23-7975-2023, 2023
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This paper presents new shortwave spectral complex refractive index and single scattering albedo data for Icelandic dust. Our results show that the imaginary part of the complex refractive index of Icelandic dust is at the upper end of the range of low-latitude dust. Furthermore, we observed that Icelandic dust is more absorbing towards the near-infrared, which we attribute to its high magnetite content. These findings are important for modeling dust aerosol radiative effects in the Arctic.
Emelie L. Graham, Cheng Wu, David M. Bell, Amelie Bertrand, Sophie L. Haslett, Urs Baltensperger, Imad El Haddad, Radovan Krejci, Ilona Riipinen, and Claudia Mohr
Atmos. Chem. Phys., 23, 7347–7362, https://doi.org/10.5194/acp-23-7347-2023, https://doi.org/10.5194/acp-23-7347-2023, 2023
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The volatility of an aerosol particle is an important parameter for describing its atmospheric lifetime. We studied the volatility of secondary organic aerosols from nitrate-initiated oxidation of three biogenic precursors with experimental methods and model simulations. We saw higher volatility than for the corresponding ozone system, and our simulations produced variable results with different parameterizations which warrant a re-evaluation of the treatment of the nitrate functional group.
Zijun Li, Noora Hyttinen, Miika Vainikka, Olli-Pekka Tikkasalo, Siegfried Schobesberger, and Taina Yli-Juuti
Atmos. Chem. Phys., 23, 6863–6877, https://doi.org/10.5194/acp-23-6863-2023, https://doi.org/10.5194/acp-23-6863-2023, 2023
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The saturation vapor pressure (psat) of low-volatility organic compounds (LVOCs) governs their partitioning between the gas and particle phases. To estimate the psat of selected LVOCs, we performed particle evaporation measurements in a residence time chamber at a temperature setting relevant to atmospheric aerosol formation and conducted state-of-the-art computational calculations. We found good agreement between the experimentally measured and model-estimated psat values for most LVOCs.
Yan Li, Falei Xu, Juan Feng, Mengying Du, Wenjun Song, Chao Li, and Wenjing Zhao
Atmos. Chem. Phys., 23, 6021–6042, https://doi.org/10.5194/acp-23-6021-2023, https://doi.org/10.5194/acp-23-6021-2023, 2023
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There is a significantly negative relationship between boreal winter North Atlantic Oscillation (NAO) and dust aerosols (DAs) in the eastern part of China (30–40°N, 105–120°E), which is not a DA source area but is severely affected by the dust events (DEs). Under the effect of the NAO negative phase, main atmospheric circulation during the DEs is characterized by variation of the transient eddy flux. The work is of reference value to the prediction of DEs and the understanding of their causes.
Ingrid de Almeida Ribeiro, Konrad Meister, and Valeria Molinero
Atmos. Chem. Phys., 23, 5623–5639, https://doi.org/10.5194/acp-23-5623-2023, https://doi.org/10.5194/acp-23-5623-2023, 2023
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Ice formation is a key atmospheric process facilitated by a wide range of aerosols. We present a method to model and interpret ice nucleation experiments and extract the distribution of the potency of nucleation sites. We use the method to optimize the conditions of laboratory sampling and extract distributions of ice nucleation temperatures from bacteria, fungi, and pollen. These reveal unforeseen subpopulations of nuclei in these systems and how they respond to changes in their environment.
Ting Lei, Hang Su, Nan Ma, Ulrich Pöschl, Alfred Wiedensohler, and Yafang Cheng
Atmos. Chem. Phys., 23, 4763–4774, https://doi.org/10.5194/acp-23-4763-2023, https://doi.org/10.5194/acp-23-4763-2023, 2023
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We investigate the hygroscopic behavior of levoglucosan and D-glucose nanoparticles using a nano-HTDMA. There is a weak size dependence of the hygroscopic growth factor of levoglucosan and D-glucose with diameters down to 20 nm, while a strong size dependence of the hygroscopic growth factor of D-glucose has been clearly observed in the size range 6 to 20 nm. The use of the DKA method leads to good agreement with the hygroscopic growth factor of glucose nanoparticles with diameters down to 6 nm.
Lubica Vetráková, Vilém Neděla, Kamila Závacká, Xin Yang, and Dominik Heger
Atmos. Chem. Phys., 23, 4463–4488, https://doi.org/10.5194/acp-23-4463-2023, https://doi.org/10.5194/acp-23-4463-2023, 2023
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Salt aerosols are important to polar atmospheric chemistry and global climate. Therefore, we utilized a unique electron microscope to identify the most suitable conditions for formation of the small salt (CsCl) particles, proxies of the aerosols, from sublimating salty snow. Very low sublimation temperature and low salt concentration are needed for formation of such particles. These observations may help us to better understand polar spring ozone depletion and bromine explosion events.
Xiaohan Li and Ian C. Bourg
Atmos. Chem. Phys., 23, 2525–2556, https://doi.org/10.5194/acp-23-2525-2023, https://doi.org/10.5194/acp-23-2525-2023, 2023
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Aerosol particles with sizes smaller than 50 nm impact cloud formation and precipitation. Representation of this effect is hindered by limited understanding of the properties of liquid water in these particles. Our simulations of aerosol particles containing salt or organic compounds reveal that water enters a less cohesive phase at droplet sizes below 4 nm. This effect causes important deviations from theoretical predictions of aerosol properties, including phase state and hygroscopic growth.
Kristian Klumpp, Claudia Marcolli, Ana Alonso-Hellweg, Christopher H. Dreimol, and Thomas Peter
Atmos. Chem. Phys., 23, 1579–1598, https://doi.org/10.5194/acp-23-1579-2023, https://doi.org/10.5194/acp-23-1579-2023, 2023
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The prerequisites of a particle surface for efficient ice nucleation are still poorly understood. This study compares the ice nucleation activity of two chemically identical but morphologically different minerals (kaolinite and halloysite). We observe, on average, not only higher ice nucleation activities for halloysite than kaolinite but also higher diversity between individual samples. We identify the particle edges as being the most likely site for ice nucleation.
Fabian Mahrt, Carolin Rösch, Kunfeng Gao, Christopher H. Dreimol, Maria A. Zawadowicz, and Zamin A. Kanji
Atmos. Chem. Phys., 23, 1285–1308, https://doi.org/10.5194/acp-23-1285-2023, https://doi.org/10.5194/acp-23-1285-2023, 2023
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Major aerosol types emitted by biomass burning include soot, ash, and charcoal particles. Here, we investigated the ice nucleation activity of 400 nm size-selected particles of two different pyrolyis-derived charcoal types in the mixed phase and cirrus cloud regime. We find that ice nucleation is constrained to cirrus cloud conditions, takes place via pore condensation and freezing, and is largely governed by the particle porosity and mineral content.
Chun Xiong, Xueyan Chen, Xiaolei Ding, Binyu Kuang, Xiangyu Pei, Zhengning Xu, Shikuan Yang, Huan Hu, and Zhibin Wang
Atmos. Chem. Phys., 22, 16123–16135, https://doi.org/10.5194/acp-22-16123-2022, https://doi.org/10.5194/acp-22-16123-2022, 2022
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Water surface tension is applied widely in current aerosol–cloud models but could be inappropriate in the presence of atmospheric surfactants. With cloud condensation nuclei (CCN) activity and atomic force microscopy (AFM) measurement results of mixed inorganic salt and dicarboxylic acid particles, we concluded that surface tension reduction and phase state should be carefully considered in aerosol–cloud interactions. Our results could help to decease uncertainties in climate models.
Bernadette Rosati, Sini Isokääntä, Sigurd Christiansen, Mads Mørk Jensen, Shamjad P. Moosakutty, Robin Wollesen de Jonge, Andreas Massling, Marianne Glasius, Jonas Elm, Annele Virtanen, and Merete Bilde
Atmos. Chem. Phys., 22, 13449–13466, https://doi.org/10.5194/acp-22-13449-2022, https://doi.org/10.5194/acp-22-13449-2022, 2022
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Sulfate aerosols have a strong influence on climate. Due to the reduction in sulfur-based fossil fuels, natural sulfur emissions play an increasingly important role. Studies investigating the climate relevance of natural sulfur aerosols are scarce. We study the water uptake of such particles in the laboratory, demonstrating a high potential to take up water and form cloud droplets. During atmospheric transit, chemical processing affects the particles’ composition and thus their water uptake.
Kanishk Gohil, Chun-Ning Mao, Dewansh Rastogi, Chao Peng, Mingjin Tang, and Akua Asa-Awuku
Atmos. Chem. Phys., 22, 12769–12787, https://doi.org/10.5194/acp-22-12769-2022, https://doi.org/10.5194/acp-22-12769-2022, 2022
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The Hybrid Activity Model (HAM) is a promising new droplet growth model that can be potentially used for the analysis of any type of atmospheric compound. HAM may potentially improve the representation of hygroscopicity of organic aerosols in large-scale global climate models (GCMs), hence reducing the uncertainties in the climate forcing due to the aerosol indirect effect.
Charbel Harb and Hosein Foroutan
Atmos. Chem. Phys., 22, 11759–11779, https://doi.org/10.5194/acp-22-11759-2022, https://doi.org/10.5194/acp-22-11759-2022, 2022
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A model representation of lake spray aerosol (LSA) ejection from freshwater breaking waves is crucial for understanding their climatic and public health impacts. We develop an LSA emission parameterization and implement it in an atmospheric model to investigate Great Lakes surface emissions. We find that the same breaking wave is likely to produce fewer aerosols in freshwater than in saltwater and that Great Lakes emissions influence the regional aerosol burden and can reach the cloud layer.
Runlong Cai, Ella Häkkinen, Chao Yan, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 11529–11541, https://doi.org/10.5194/acp-22-11529-2022, https://doi.org/10.5194/acp-22-11529-2022, 2022
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The influences of new particle formation on the climate and air quality are governed by particle survival, which has been under debate due to uncertainties in the coagulation sink. Here we measure the coagulation coefficient of sub-10 nm particles and demonstrate that collisions between the freshly nucleated and background particles can effectively lead to coagulation. We further show that the effective coagulation sink is consistent with the new particle formation measured in urban Beijing.
Lamei Shi, Jiahua Zhang, Da Zhang, Jingwen Wang, Xianglei Meng, Yuqin Liu, and Fengmei Yao
Atmos. Chem. Phys., 22, 11255–11274, https://doi.org/10.5194/acp-22-11255-2022, https://doi.org/10.5194/acp-22-11255-2022, 2022
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Dust impacts climate and human life. Analyzing the interdecadal change in dust activity and its influence factors is crucial for disaster mitigation. Based on a linear regression method, this study revealed the interdecadal variability of relationships between ENSO and dust over northwestern South Asia from 1982 to 2014 and analyzed the effects of atmospheric factors on this interdecadal variability. The result sheds new light on numerical simulation involving the interdecadal variation of dust.
Bighnaraj Sarangi, Darrel Baumgardner, Benjamin Bolaños-Rosero, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 22, 9647–9661, https://doi.org/10.5194/acp-22-9647-2022, https://doi.org/10.5194/acp-22-9647-2022, 2022
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Here, the fluorescent characteristics and cloud-forming efficiency of aerosols at an urban site in Puerto Rico are discussed. The results from this pilot study highlight the capabilities of ultraviolet-induced fluorescence (UV-IF) measurements for characterizing the properties of fluorescing aerosol particles, as they relate to the daily evolution of primary biological aerosol particles. This work has established a database of measurements on which future, longer-term studies will be initiated.
Rani Jeong, Joseph Lilek, Andreas Zuend, Rongshuang Xu, Man Nin Chan, Dohyun Kim, Hi Gyu Moon, and Mijung Song
Atmos. Chem. Phys., 22, 8805–8817, https://doi.org/10.5194/acp-22-8805-2022, https://doi.org/10.5194/acp-22-8805-2022, 2022
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In this study, the viscosities of particles of sucrose–H2O, AS–H2O, and sucrose–AS–H2O for OIRs of 4:1, 1:1, and 1:4 for decreasing RH, were quantified by poke-and-flow and bead-mobility techniques at 293 ± 1 K. Based on the viscosity results, the particles of binary and ternary systems ranged from liquid to semisolid, and even the solid state depending on the RH. Moreover, we compared the measured viscosities of ternary systems to the predicted viscosities with excellent agreement.
Minxia Shen, Kin Fai Ho, Wenting Dai, Suixin Liu, Ting Zhang, Qiyuan Wang, Jingjing Meng, Judith C. Chow, John G. Watson, Junji Cao, and Jianjun Li
Atmos. Chem. Phys., 22, 7489–7504, https://doi.org/10.5194/acp-22-7489-2022, https://doi.org/10.5194/acp-22-7489-2022, 2022
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Looking at characteristics and δ13C compositions of dicarboxylic acids and related compounds in BB aerosols, we used a combined combustion and aging system to generate fresh and aged aerosols from burning straw. The results showed the emission factors (EFaged) of total diacids of aging experiments were around an order of magnitude higher than EFfresh. This meant that dicarboxylic acids are involved with secondary photochemical processes in the atmosphere rather than primary emissions from BB.
Jonas K. F. Jakobsson, Deepak B. Waman, Vaughan T. J. Phillips, and Thomas Bjerring Kristensen
Atmos. Chem. Phys., 22, 6717–6748, https://doi.org/10.5194/acp-22-6717-2022, https://doi.org/10.5194/acp-22-6717-2022, 2022
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Long-lived cold-layer clouds at subzero temperatures are observed to be remarkably persistent in their generation of ice particles and snow precipitation. There is uncertainty about why this is so. This motivates the present lab study to observe the long-term ice-nucleating ability of aerosol samples from the real troposphere. Time dependence of their ice nucleation is observed to be weak in lab experiments exposing the samples to isothermal conditions for up to about 10 h.
Kunfeng Gao, Chong-Wen Zhou, Eszter J. Barthazy Meier, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 5331–5364, https://doi.org/10.5194/acp-22-5331-2022, https://doi.org/10.5194/acp-22-5331-2022, 2022
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Incomplete combustion of fossil fuel produces carbonaceous particles called soot. These particles can affect cloud formation by acting as centres for droplet or ice formation. The atmospheric residence time of soot particles is of the order of days to weeks, which can result in them becoming coated by various trace species in the atmosphere such as acids. In this study, we quantify the cirrus cloud-forming ability of soot particles coated with the atmospherically ubiquitous sulfuric acid.
Kunfeng Gao, Franz Friebel, Chong-Wen Zhou, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 4985–5016, https://doi.org/10.5194/acp-22-4985-2022, https://doi.org/10.5194/acp-22-4985-2022, 2022
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Soot particles impact cloud formation and radiative properties in the upper atmosphere where aircraft emit carbonaceous particles. We use cloud chambers to mimic the upper atmosphere temperature and humidity to test the influence of the morphology of the soot particles on ice cloud formation. For particles larger than 200 nm, the compacted (densified) samples have a higher affinity for ice crystal formation in the cirrus regime than the fluffy (un-compacted) soot particles of the same sample.
Joel Kuula, Hilkka Timonen, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Tareq Hussein, Pak Lun Fung, Sasu Tarkoma, Mikko Laakso, Erkka Saukko, Aino Ovaska, Markku Kulmala, Ari Karppinen, Lasse Johansson, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 4801–4808, https://doi.org/10.5194/acp-22-4801-2022, https://doi.org/10.5194/acp-22-4801-2022, 2022
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Modern and up-to-date policies and air quality management strategies are instrumental in tackling global air pollution. As the European Union is preparing to revise Ambient Air Quality Directive 2008/50/EC, this paper initiates discussion on selected features of the directive that we believe would benefit from a reassessment. The scientific community has the most recent and deepest understanding of air pollution; thus, its contribution is essential.
Yu Wang, Aristeidis Voliotis, Dawei Hu, Yunqi Shao, Mao Du, Ying Chen, Judith Kleinheins, Claudia Marcolli, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 4149–4166, https://doi.org/10.5194/acp-22-4149-2022, https://doi.org/10.5194/acp-22-4149-2022, 2022
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Aerosol water uptake plays a key role in atmospheric physicochemical processes. We designed chamber experiments on aerosol water uptake of secondary organic aerosol (SOA) from mixed biogenic and anthropogenic precursors with inorganic seed. Our results highlight this chemical composition influences the reconciliation of the sub- and super-saturated water uptake, providing laboratory evidence for understanding the chemical controls of water uptake of the multi-component aerosol.
Shuang Han, Juan Hong, Qingwei Luo, Hanbing Xu, Haobo Tan, Qiaoqiao Wang, Jiangchuan Tao, Yaqing Zhou, Long Peng, Yao He, Jingnan Shi, Nan Ma, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 3985–4004, https://doi.org/10.5194/acp-22-3985-2022, https://doi.org/10.5194/acp-22-3985-2022, 2022
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We present the hygroscopicity of 23 organic species with different physicochemical properties using a hygroscopicity tandem differential mobility analyzer (HTDMA) and compare the results with previous studies. Based on the hygroscopicity parameter κ, the influence of different physicochemical properties that potentially drive hygroscopicity, such as the functionality, water solubility, molar volume, and O : C ratio of organics, are examined separately.
Kimmo Korhonen, Thomas Bjerring Kristensen, John Falk, Vilhelm B. Malmborg, Axel Eriksson, Louise Gren, Maja Novakovic, Sam Shamun, Panu Karjalainen, Lassi Markkula, Joakim Pagels, Birgitta Svenningsson, Martin Tunér, Mika Komppula, Ari Laaksonen, and Annele Virtanen
Atmos. Chem. Phys., 22, 1615–1631, https://doi.org/10.5194/acp-22-1615-2022, https://doi.org/10.5194/acp-22-1615-2022, 2022
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We investigated the ice-nucleating abilities of particulate emissions from a modern diesel engine using the portable ice-nuclei counter SPIN, a continuous-flow diffusion chamber instrument. Three different fuels were studied without blending, including fossil diesel and two renewable fuels, testing different emission aftertreatment systems and photochemical aging. We found that the diesel emissions were inefficient ice nuclei, and aging had no or little effect on their ice-nucleating abilities.
Noora Hyttinen, Iida Pullinen, Aki Nissinen, Siegfried Schobesberger, Annele Virtanen, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 1195–1208, https://doi.org/10.5194/acp-22-1195-2022, https://doi.org/10.5194/acp-22-1195-2022, 2022
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Accurate saturation vapor pressure estimates of atmospherically relevant organic compounds are critical for modeling secondary organic aerosol (SOA) formation. We investigated vapor pressures of highly oxygenated SOA constituents using state-of-the-art computational and experimental methods. We found a good agreement between low and extremely low vapor pressures estimated using the two methods, and the smallest molecules detected in our experiment were likely products of thermal decomposition.
Dawei Hu, M. Rami Alfarra, Kate Szpek, Justin M. Langridge, Michael I. Cotterell, Claire Belcher, Ian Rule, Zixia Liu, Chenjie Yu, Yunqi Shao, Aristeidis Voliotis, Mao Du, Brett Smith, Greg Smallwood, Prem Lobo, Dantong Liu, Jim M. Haywood, Hugh Coe, and James D. Allan
Atmos. Chem. Phys., 21, 16161–16182, https://doi.org/10.5194/acp-21-16161-2021, https://doi.org/10.5194/acp-21-16161-2021, 2021
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Here, we developed new techniques for investigating these properties in the laboratory and applied these to BC and BrC from different sources, including diesel exhaust, inverted propane flame and wood combustion. These have allowed us to quantify the changes in shape and chemical composition of different soots according to source and variables such as the moisture content of wood.
Mariam Fawaz, Anita Avery, Timothy B. Onasch, Leah R. Williams, and Tami C. Bond
Atmos. Chem. Phys., 21, 15605–15618, https://doi.org/10.5194/acp-21-15605-2021, https://doi.org/10.5194/acp-21-15605-2021, 2021
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Biomass burning is responsible for 90 % of the emissions of primary organic aerosols to the atmosphere. Emissions from biomass burning sources are considered chaotic. In this work, we developed a controlled experimental approach to understand the controlling factors in emission. Our results showed that emissions are repeatable and deterministic and that emissions from wood can be constrained.
Soleil E. Worthy, Anand Kumar, Yu Xi, Jingwei Yun, Jessie Chen, Cuishan Xu, Victoria E. Irish, Pierre Amato, and Allan K. Bertram
Atmos. Chem. Phys., 21, 14631–14648, https://doi.org/10.5194/acp-21-14631-2021, https://doi.org/10.5194/acp-21-14631-2021, 2021
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We studied the effect of (NH4)2SO4 on the immersion freezing of non-mineral dust ice-nucleating substances (INSs) and mineral dusts. (NH4)2SO4 had no effect on the median freezing temperature of 9 of the 10 tested non-mineral dust INSs, slightly decreased that of the other, and increased that of all the mineral dusts. The difference in the response of mineral dust and non-mineral dust INSs to (NH4)2SO4 suggests that they nucleate ice and/or interact with (NH4)2SO4 via different mechanisms.
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Short summary
We assessed how well the organic aerosol particle composition and viscosity can be captured by optimizing process models to match particle evaporation data. We performed the analysis for both artificial and real evaporation data and tested two optimization algorithms. Our findings show that the optimization method yields a good estimate for the studied properties. The timescale of the evaporation data and particle size was found to be important in identifying the volatility of organic compounds.
We assessed how well the organic aerosol particle composition and viscosity can be captured by...
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