Articles | Volume 22, issue 14
https://doi.org/10.5194/acp-22-9647-2022
© Author(s) 2022. 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-22-9647-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Measurement report
| 
29 Jul 2022
Measurement report |
| 29 Jul 2022
| 29 Jul 2022
Measurement report: An exploratory study of fluorescence and cloud condensation nuclei activity of urban aerosols in San Juan, Puerto Rico
Bighnaraj Sarangi
CORRESPONDING AUTHOR
Department of Environmental Sciences, University of Puerto Rico –
Río Piedras Campus, San Juan, Puerto Rico, USA
Darrel Baumgardner
Droplet Measurement Technologies, LLC, Longmont, Colorado, USA
Benjamin Bolaños-Rosero
Department of Microbiology and Medical Zoology, School of Medicine, University of Puerto
Rico – Medical Sciences Campus, San Juan, Puerto Rico, USA
Olga L. Mayol-Bracero
Department of Environmental Sciences, University of Puerto Rico –
Río Piedras Campus, San Juan, Puerto Rico, USA
now at: Environment and Climate Sciences Department, Brookhaven
National Laboratory, Upton, New York, USA
Related authors
Bighnaraj Sarangi, Darrel Baumgardner, Ana Isabel Calvo, Benjamin Bolaños-Rosero, Roberto Fraile, Alberto Rodríguez-Fernández, Delia Fernández-González, Carlos Blanco-Alegre, Cátia Gonçalves, Estela D. Vicente, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 25, 843–865, https://doi.org/10.5194/acp-25-843-2025, https://doi.org/10.5194/acp-25-843-2025, 2025
Short summary
Short summary
Measurements of fluorescing aerosol particle properties have been made during two major African dust events, one over the island of Puerto Rico and the other over the city of León, Spain. The measurements were made with two wideband integrated bioaerosol spectrometers. A significant change in the background aerosol properties, at both locations, is observed when the dust is in the respective regions.
Bighnaraj Sarangi, Darrel Baumgardner, Ana Isabel Calvo, Benjamin Bolaños-Rosero, Roberto Fraile, Alberto Rodríguez-Fernández, Delia Fernández-González, Carlos Blanco-Alegre, Cátia Gonçalves, Estela D. Vicente, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 25, 843–865, https://doi.org/10.5194/acp-25-843-2025, https://doi.org/10.5194/acp-25-843-2025, 2025
Short summary
Short summary
Measurements of fluorescing aerosol particle properties have been made during two major African dust events, one over the island of Puerto Rico and the other over the city of León, Spain. The measurements were made with two wideband integrated bioaerosol spectrometers. A significant change in the background aerosol properties, at both locations, is observed when the dust is in the respective regions.
Mahen Konwar, Benjamin Werden, Edward C. Fortner, Sudarsan Bera, Mercy Varghese, Subharthi Chowdhuri, Kurt Hibert, Philip Croteau, John Jayne, Manjula Canagaratna, Neelam Malap, Sandeep Jayakumar, Shivsai A. Dixit, Palani Murugavel, Duncan Axisa, Darrel Baumgardner, Peter F. DeCarlo, Doug R. Worsnop, and Thara Prabhakaran
Atmos. Meas. Tech., 17, 2387–2400, https://doi.org/10.5194/amt-17-2387-2024, https://doi.org/10.5194/amt-17-2387-2024, 2024
Short summary
Short summary
In a warm cloud seeding experiment hygroscopic particles are released to alter cloud processes to induce early raindrops. During the Cloud–Aerosol Interaction and Precipitation Enhancement Experiment, airborne mini aerosol mass spectrometers analyse the particles on which clouds form. The seeded clouds showed higher concentrations of chlorine and potassium, the oxidizing agents of flares. Small cloud droplet concentrations increased, and seeding particles were detected in deep cloud depths.
Graciela B. Raga, Darrel Baumgardner, Blanca Rios, Yanet Díaz-Esteban, Alejandro Jaramillo, Martin Gallagher, Bastien Sauvage, Pawel Wolff, and Gary Lloyd
Atmos. Chem. Phys., 22, 2269–2292, https://doi.org/10.5194/acp-22-2269-2022, https://doi.org/10.5194/acp-22-2269-2022, 2022
Short summary
Short summary
The In-Service Aircraft for a Global Observing System (IAGOS) is a small fleet of commercial aircraft that carry a suite of meteorological, gas, aerosol, and cloud sensors and have been measuring worldwide for almost 9 years, since late 2011. Extreme ice events (EIEs) have been identified from the IAGOS cloud measurements and linked to surface emissions for biomass and fossil fuel consumption. The results reported here are highly relevant for climate change and flight operations forecasting.
Elvis Torres-Delgado, Darrel Baumgardner, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 21, 18011–18027, https://doi.org/10.5194/acp-21-18011-2021, https://doi.org/10.5194/acp-21-18011-2021, 2021
Short summary
Short summary
African dust aerosols can travel thousands of kilometers and reach the Caribbean and other places, where they can serve as ice and cloud condensation nuclei and alter precipitation patterns. Cloud microphysical properties (droplet number and size) were measured in a Caribbean tropical montane cloud forest along with models and satellite products. The results of the study suggest that meteorology and air mass history are more important for cloud processes than aerosols transported from Africa.
Fernanda Córdoba, Carolina Ramírez-Romero, Diego Cabrera, Graciela B. Raga, Javier Miranda, Harry Alvarez-Ospina, Daniel Rosas, Bernardo Figueroa, Jong Sung Kim, Jacqueline Yakobi-Hancock, Talib Amador, Wilfrido Gutierrez, Manuel García, Allan K. Bertram, Darrel Baumgardner, and Luis A. Ladino
Atmos. Chem. Phys., 21, 4453–4470, https://doi.org/10.5194/acp-21-4453-2021, https://doi.org/10.5194/acp-21-4453-2021, 2021
Short summary
Short summary
Most precipitation from deep clouds over the continents and in the intertropical convergence zone is strongly influenced by the presence of ice crystals whose formation requires the presence of aerosol particles. In the present study, the ability of three different aerosol types (i.e., marine aerosol, biomass burning, and African dust) to facilitate ice particle formation was assessed in the Yucatán Peninsula, Mexico.
Carolina Ramírez-Romero, Alejandro Jaramillo, María F. Córdoba, Graciela B. Raga, Javier Miranda, Harry Alvarez-Ospina, Daniel Rosas, Talib Amador, Jong Sung Kim, Jacqueline Yakobi-Hancock, Darrel Baumgardner, and Luis A. Ladino
Atmos. Chem. Phys., 21, 239–253, https://doi.org/10.5194/acp-21-239-2021, https://doi.org/10.5194/acp-21-239-2021, 2021
Short summary
Short summary
Field measurements were conducted to confirm the arrival of African dust on the Yucatàn Peninsula. Aerosol particles were monitored at ground level by different online and off-line sensors. Several particulate matter peaks were observed with a relative increase in their levels of up to 500 % with respect to background conditions. Based on the chemical composition, back trajectories, vertical profiles, reanalysis, and satellite images, it was found that the peaks are linked to African dust.
Lester Alfonso, Graciela B. Raga, and Darrel Baumgardner
Atmos. Chem. Phys., 19, 14917–14932, https://doi.org/10.5194/acp-19-14917-2019, https://doi.org/10.5194/acp-19-14917-2019, 2019
Short summary
Short summary
The aim of this paper is to find some observational evidence of gel formation in clouds, by analyzing the distribution of the largest droplet at an early stage of cloud formation, and to show that the mass of the gel (
lucky droplet) is a mixture of Gaussian and Gumbel distributions. The results obtained may help advance the understanding of precipitation formation and are a novel application of the theory of critical phenomena in cloud physics.
Viswanathan Bringi, Merhala Thurai, and Darrel Baumgardner
Atmos. Meas. Tech., 11, 1377–1384, https://doi.org/10.5194/amt-11-1377-2018, https://doi.org/10.5194/amt-11-1377-2018, 2018
Short summary
Short summary
Raindrop fall velocities are important for rain rate estimation, soil erosion studies and in numerical modelling of rain formation in clouds. The assumption that the fall velocity is uniquely related to drop size is made inherently based on laboratory measurements under still air conditions from nearly 68 years ago. There have been very few measurements of drop fall speeds in natural rain under both still and turbulent wind conditions. We report on fall speed measurements in natural rain shafts.
Anja Costa, Jessica Meyer, Armin Afchine, Anna Luebke, Gebhard Günther, James R. Dorsey, Martin W. Gallagher, Andre Ehrlich, Manfred Wendisch, Darrel Baumgardner, Heike Wex, and Martina Krämer
Atmos. Chem. Phys., 17, 12219–12238, https://doi.org/10.5194/acp-17-12219-2017, https://doi.org/10.5194/acp-17-12219-2017, 2017
Short summary
Short summary
The paper presents 38 h of in situ cloud spectrometer observations of microphysical cloud properties in the Arctic, midlatitudes and tropics. The clouds are classified via particle concentrations, size distributions, and – as a novelty – small particle aspherical fractions. Cloud-type profiles are given for different temperatures and locations. The results confine regions where different cloud transformation processes occurred and emphasise the importance of small particle shape detection.
Ulrich Schumann, Robert Baumann, Darrel Baumgardner, Sarah T. Bedka, David P. Duda, Volker Freudenthaler, Jean-Francois Gayet, Andrew J. Heymsfield, Patrick Minnis, Markus Quante, Ehrhard Raschke, Hans Schlager, Margarita Vázquez-Navarro, Christiane Voigt, and Zhien Wang
Atmos. Chem. Phys., 17, 403–438, https://doi.org/10.5194/acp-17-403-2017, https://doi.org/10.5194/acp-17-403-2017, 2017
Short summary
Short summary
The initially linear clouds often seen behind aircraft are known as contrails. Contrails are prototype cirrus clouds forming under well-known conditions, but with less certain life cycle and climate effects. This paper collects contrail data from a large set of measurements and compares them among each other and with models. The observations show consistent contrail properties over a wide range of aircraft and atmosphere conditions. The dataset is available for further research.
Ana Graciela Ulke, Marcela M. Torres Brizuela, Graciela B. Raga, and Darrel Baumgardner
Nat. Hazards Earth Syst. Sci., 16, 2159–2175, https://doi.org/10.5194/nhess-16-2159-2016, https://doi.org/10.5194/nhess-16-2159-2016, 2016
Short summary
Short summary
The eruption in June 2011 of the Puyehue-Cordón Caulle Volcanic Complex (Chile) impacted air traffic around the Southern Hemisphere for several months. The ash deposited in vast areas of the Patagonian steppe was subjected to the strong wind conditions prevalent during the austral winter and spring. An ash resuspension event impacted Buenos Aires and resulted in the closure of airports in the area on 16 October 2011. Measurements of aerosol properties clearly indicate the enhanced concentrations
Mark Hernandez, Anne E. Perring, Kevin McCabe, Greg Kok, Gary Granger, and Darrel Baumgardner
Atmos. Meas. Tech., 9, 3283–3292, https://doi.org/10.5194/amt-9-3283-2016, https://doi.org/10.5194/amt-9-3283-2016, 2016
Short summary
Short summary
We have performed laboratory experiments examining a large set of known bacterial, fungal and pollen species using a Wideband Integrated Bioaerosol Sensor (WIBS). The instrumental response is shown to be sufficiently distinct for these classes of particles to distinguish between them, and this library will provide a framework for interpretation of UV-induced fluorescence measurements of atmospheric bioaerosol. Atmospheric implications and instrumental considerations are discussed.
Anna E. Luebke, Armin Afchine, Anja Costa, Jens-Uwe Grooß, Jessica Meyer, Christian Rolf, Nicole Spelten, Linnea M. Avallone, Darrel Baumgardner, and Martina Krämer
Atmos. Chem. Phys., 16, 5793–5809, https://doi.org/10.5194/acp-16-5793-2016, https://doi.org/10.5194/acp-16-5793-2016, 2016
Short summary
Short summary
In this study, we present observational evidence to show that two distinct types of cirrus clouds exist – in situ origin and liquid origin cirrus. These two types differ by their formation mechanism and other properties. Airborne, in-cloud measurements of cloud ice water content (IWC), ice crystal concentration (Nice), and ice crystal size from the 2014 ML-CIRRUS campaign provide cloud samples that have been divided and analyzed according to their origin type.
María José Granados-Muñoz, Juan Antonio Bravo-Aranda, Darrel Baumgardner, Juan Luis Guerrero-Rascado, Daniel Pérez-Ramírez, Francisco Navas-Guzmán, Igor Veselovskii, Hassan Lyamani, Antonio Valenzuela, Francisco José Olmo, Gloria Titos, Javier Andrey, Anatoli Chaikovsky, Oleg Dubovik, Manuel Gil-Ojeda, and Lucas Alados-Arboledas
Atmos. Meas. Tech., 9, 1113–1133, https://doi.org/10.5194/amt-9-1113-2016, https://doi.org/10.5194/amt-9-1113-2016, 2016
Short summary
Short summary
A Saharan dust event is studied in detail using ground-based remote sensing measurements from lidar technology, as well as sun- and star-photometers. The use of combined techniques allows for obtaining both profiles and column-integrated microphysical properties during night and daytime. Besides, for the first time a validation of the CAS-POL depolarization measurements and LIRIC profiles is performed, thanks to the availability of aircraft in situ measurements, obtaining reasonable agreement.
Martina Krämer, Christian Rolf, Anna Luebke, Armin Afchine, Nicole Spelten, Anja Costa, Jessica Meyer, Martin Zöger, Jessica Smith, Robert L. Herman, Bernhard Buchholz, Volker Ebert, Darrel Baumgardner, Stephan Borrmann, Marcus Klingebiel, and Linnea Avallone
Atmos. Chem. Phys., 16, 3463–3483, https://doi.org/10.5194/acp-16-3463-2016, https://doi.org/10.5194/acp-16-3463-2016, 2016
Short summary
Short summary
A guide to cirrus clouds is compiled from extensive model simulations and aircraft observations. Two types of cirrus are found: rather thin in situ cirrus that form directly as ice and thicker liquid origin cirrus consisting of uplifted frozen liquid drops. Over Europe, thinner in situ and liquid origin cirrus occur often together with frontal systems, while over the US and the Tropics, thick liquid origin cirrus formed in large convective systems are detected more frequently.
A. Retama, D. Baumgardner, G. B. Raga, G. R. McMeeking, and J. W. Walker
Atmos. Chem. Phys., 15, 9693–9709, https://doi.org/10.5194/acp-15-9693-2015, https://doi.org/10.5194/acp-15-9693-2015, 2015
Short summary
Short summary
Extended measurements of equivalent black carbon (eBC) derived from light absorption measurements have been made with a PAX over a 13 month period. The daily trends in eBC and other co-pollutants are evaluated with respect to season.
The primary factors that led to large changes between the wet and dry seasons are the accelerated vertical mixing of boundary layer and free tropospheric air, by the formation of clouds and decreased actinic flux that reduces the production of ozone.
K. Beswick, D. Baumgardner, M. Gallagher, A. Volz-Thomas, P. Nedelec, K.-Y. Wang, and S. Lance
Atmos. Meas. Tech., 7, 1443–1457, https://doi.org/10.5194/amt-7-1443-2014, https://doi.org/10.5194/amt-7-1443-2014, 2014
G. B. Raga, D. Baumgardner, A. G. Ulke, M. Torres Brizuela, and B. Kucienska
Nat. Hazards Earth Syst. Sci., 13, 2319–2330, https://doi.org/10.5194/nhess-13-2319-2013, https://doi.org/10.5194/nhess-13-2319-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Laboratory Studies | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Viscosity of aqueous ammonium nitrate–organic particles: equilibrium partitioning may be a reasonable assumption for most tropospheric conditions
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
Measurement report: The ice-nucleating activity of lichen sampled in a northern European boreal forest
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?
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
Heterogeneous ice nucleation ability of aerosol particles generated from Arctic sea surface microlayer and surface seawater samples at cirrus temperatures
Aerosol formation and growth rates from chamber experiments using Kalman smoothing
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Ulrike Proske, Michael P. Adams, Grace C. E. Porter, Mark Holden, Jaana Bäck, and Benjamin J. Murray
EGUsphere, https://doi.org/10.5194/egusphere-2023-2780, https://doi.org/10.5194/egusphere-2023-2780, 2024
Short summary
Short summary
Ice nucleating particles aid freezing of water droplets in clouds and thus modify clouds' properties. During a campaign in the boreal forest in Finland, substantial concentrations of biological ice nucleating particles were observed, despite many of their potential biological sources being snow covered. We sampled lichen in this location and tested its ice nculeation ability in the laboratory. We find that indeed the lichen harbours INPs, which may be important in such snow covered environments.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
This work is the first study to simultaneously analyze the number concentrations and species of insoluble particles in hailstones. The size distribution of insoluble particles for each species vary greatly in different hailstorms but little in shells. Two classic size distribution modes of organics and dust were fitted for the description of insoluble particles in deep convection. Combining this study with future experiments will lead to refinement of weather and climate models.
Yueling Chen, Xiangyu Pei, Huichao Liu, Yikan Meng, Zhengning Xu, Fei Zhang, Chun Xiong, Thomas C. Preston, and Zhibin Wang
Atmos. Chem. Phys., 23, 10255–10265, https://doi.org/10.5194/acp-23-10255-2023, https://doi.org/10.5194/acp-23-10255-2023, 2023
Short summary
Short summary
The impact of acidity on the phase transition behavior of levitated aerosol particles was examined. Our results revealed that lower acidity decreases the separation relative humidity of aerosol droplets mixed with ammonium sulfate and secondary organic aerosol proxy. Our research suggests that in real atmospheric conditions, with the high acidity found in many ambient aerosol particles, droplets encounter heightened impediments to phase separation and tend to display a homogeneous structure.
Mária Lbadaoui-Darvas, Ari Laaksonen, and Athanasios Nenes
Atmos. Chem. Phys., 23, 10057–10074, https://doi.org/10.5194/acp-23-10057-2023, https://doi.org/10.5194/acp-23-10057-2023, 2023
Short summary
Short summary
Heterogeneous ice nucleation is the main ice formation mechanism in clouds. The mechanism of different freezing modes is to date unknown, which results in large model biases. Experiments do not allow for direct observation of ice nucleation at its native resolution. This work uses first principles molecular simulations to determine the mechanism of the least-understood ice nucleation mode and link it to adsorption through a novel modeling framework that unites ice and droplet formation.
Carynelisa Haspel, Cuiqi Zhang, Martin J. Wolf, Daniel J. Cziczo, and Maor Sela
Atmos. Chem. Phys., 23, 10091–10115, https://doi.org/10.5194/acp-23-10091-2023, https://doi.org/10.5194/acp-23-10091-2023, 2023
Short summary
Short summary
Small particles, commonly termed aerosols, can be found throughout the atmosphere and come from both natural and anthropogenic sources. One important type of aerosol is black carbon (BC). In this study, we conducted laboratory measurements of light scattering by particles meant to mimic atmospheric BC and compared them to calculations of scattering. We find that it is likely that calculations underpredict the scattering by BC particles of certain polarizations of light in certain directions.
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
Short summary
Short summary
In hydration, an apparent water diffusion hindrance by an organic surfactant shell was confirmed, raising the inorganic deliquescence relative humidity (RH) to a nearly saturated condition. In dehydration, phase separations were observed for inorganic surfactant systems, showing a strong dependence on the organic molecular
oxygen-to-carbon ratio. Our results could improve fundamental knowledge about aerosol mixing states and decrease uncertainty in model estimations of global radiative effects.
Clarissa Baldo, Paola Formenti, Claudia Di Biagio, Gongda Lu, Congbo Song, Mathieu Cazaunau, Edouard Pangui, Jean-Francois Doussin, Pavla Dagsson-Waldhauserova, Olafur Arnalds, David Beddows, A. Robert MacKenzie, and Zongbo Shi
Atmos. Chem. Phys., 23, 7975–8000, https://doi.org/10.5194/acp-23-7975-2023, https://doi.org/10.5194/acp-23-7975-2023, 2023
Short summary
Short summary
This paper presents new shortwave spectral complex refractive index and single scattering albedo data for Icelandic dust. Our results show that the imaginary part of the complex refractive index of Icelandic dust is at the upper end of the range of low-latitude dust. Furthermore, we observed that Icelandic dust is more absorbing towards the near-infrared, which we attribute to its high magnetite content. These findings are important for modeling dust aerosol radiative effects in the Arctic.
Emelie L. Graham, Cheng Wu, David M. Bell, Amelie Bertrand, Sophie L. Haslett, Urs Baltensperger, Imad El Haddad, Radovan Krejci, Ilona Riipinen, and Claudia Mohr
Atmos. Chem. Phys., 23, 7347–7362, https://doi.org/10.5194/acp-23-7347-2023, https://doi.org/10.5194/acp-23-7347-2023, 2023
Short summary
Short summary
The volatility of an aerosol particle is an important parameter for describing its atmospheric lifetime. We studied the volatility of secondary organic aerosols from nitrate-initiated oxidation of three biogenic precursors with experimental methods and model simulations. We saw higher volatility than for the corresponding ozone system, and our simulations produced variable results with different parameterizations which warrant a re-evaluation of the treatment of the nitrate functional group.
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
Short summary
Short summary
The saturation vapor pressure (psat) of low-volatility organic compounds (LVOCs) governs their partitioning between the gas and particle phases. To estimate the psat of selected LVOCs, we performed particle evaporation measurements in a residence time chamber at a temperature setting relevant to atmospheric aerosol formation and conducted state-of-the-art computational calculations. We found good agreement between the experimentally measured and model-estimated psat values for most LVOCs.
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
Short summary
Short summary
There is a significantly negative relationship between boreal winter North Atlantic Oscillation (NAO) and dust aerosols (DAs) in the eastern part of China (30–40°N, 105–120°E), which is not a DA source area but is severely affected by the dust events (DEs). Under the effect of the NAO negative phase, main atmospheric circulation during the DEs is characterized by variation of the transient eddy flux. The work is of reference value to the prediction of DEs and the understanding of their causes.
Ingrid de Almeida Ribeiro, Konrad Meister, and Valeria Molinero
Atmos. Chem. Phys., 23, 5623–5639, https://doi.org/10.5194/acp-23-5623-2023, https://doi.org/10.5194/acp-23-5623-2023, 2023
Short summary
Short summary
Ice formation is a key atmospheric process facilitated by a wide range of aerosols. We present a method to model and interpret ice nucleation experiments and extract the distribution of the potency of nucleation sites. We use the method to optimize the conditions of laboratory sampling and extract distributions of ice nucleation temperatures from bacteria, fungi, and pollen. These reveal unforeseen subpopulations of nuclei in these systems and how they respond to changes in their environment.
Ting Lei, Hang Su, Nan Ma, Ulrich Pöschl, Alfred Wiedensohler, and Yafang Cheng
Atmos. Chem. Phys., 23, 4763–4774, https://doi.org/10.5194/acp-23-4763-2023, https://doi.org/10.5194/acp-23-4763-2023, 2023
Short summary
Short summary
We investigate the hygroscopic behavior of levoglucosan and D-glucose nanoparticles using a nano-HTDMA. There is a weak size dependence of the hygroscopic growth factor of levoglucosan and D-glucose with diameters down to 20 nm, while a strong size dependence of the hygroscopic growth factor of D-glucose has been clearly observed in the size range 6 to 20 nm. The use of the DKA method leads to good agreement with the hygroscopic growth factor of glucose nanoparticles with diameters down to 6 nm.
Lubica Vetráková, Vilém Neděla, Kamila Závacká, Xin Yang, and Dominik Heger
Atmos. Chem. Phys., 23, 4463–4488, https://doi.org/10.5194/acp-23-4463-2023, https://doi.org/10.5194/acp-23-4463-2023, 2023
Short summary
Short summary
Salt aerosols are important to polar atmospheric chemistry and global climate. Therefore, we utilized a unique electron microscope to identify the most suitable conditions for formation of the small salt (CsCl) particles, proxies of the aerosols, from sublimating salty snow. Very low sublimation temperature and low salt concentration are needed for formation of such particles. These observations may help us to better understand polar spring ozone depletion and bromine explosion events.
Xiaohan Li and Ian C. Bourg
Atmos. Chem. Phys., 23, 2525–2556, https://doi.org/10.5194/acp-23-2525-2023, https://doi.org/10.5194/acp-23-2525-2023, 2023
Short summary
Short summary
Aerosol particles with sizes smaller than 50 nm impact cloud formation and precipitation. Representation of this effect is hindered by limited understanding of the properties of liquid water in these particles. Our simulations of aerosol particles containing salt or organic compounds reveal that water enters a less cohesive phase at droplet sizes below 4 nm. This effect causes important deviations from theoretical predictions of aerosol properties, including phase state and hygroscopic growth.
Kristian Klumpp, Claudia Marcolli, Ana Alonso-Hellweg, Christopher H. Dreimol, and Thomas Peter
Atmos. Chem. Phys., 23, 1579–1598, https://doi.org/10.5194/acp-23-1579-2023, https://doi.org/10.5194/acp-23-1579-2023, 2023
Short summary
Short summary
The prerequisites of a particle surface for efficient ice nucleation are still poorly understood. This study compares the ice nucleation activity of two chemically identical but morphologically different minerals (kaolinite and halloysite). We observe, on average, not only higher ice nucleation activities for halloysite than kaolinite but also higher diversity between individual samples. We identify the particle edges as being the most likely site for ice nucleation.
Fabian Mahrt, Carolin Rösch, Kunfeng Gao, Christopher H. Dreimol, Maria A. Zawadowicz, and Zamin A. Kanji
Atmos. Chem. Phys., 23, 1285–1308, https://doi.org/10.5194/acp-23-1285-2023, https://doi.org/10.5194/acp-23-1285-2023, 2023
Short summary
Short summary
Major aerosol types emitted by biomass burning include soot, ash, and charcoal particles. Here, we investigated the ice nucleation activity of 400 nm size-selected particles of two different pyrolyis-derived charcoal types in the mixed phase and cirrus cloud regime. We find that ice nucleation is constrained to cirrus cloud conditions, takes place via pore condensation and freezing, and is largely governed by the particle porosity and mineral content.
Chun Xiong, Xueyan Chen, Xiaolei Ding, Binyu Kuang, Xiangyu Pei, Zhengning Xu, Shikuan Yang, Huan Hu, and Zhibin Wang
Atmos. Chem. Phys., 22, 16123–16135, https://doi.org/10.5194/acp-22-16123-2022, https://doi.org/10.5194/acp-22-16123-2022, 2022
Short summary
Short summary
Water surface tension is applied widely in current aerosol–cloud models but could be inappropriate in the presence of atmospheric surfactants. With cloud condensation nuclei (CCN) activity and atomic force microscopy (AFM) measurement results of mixed inorganic salt and dicarboxylic acid particles, we concluded that surface tension reduction and phase state should be carefully considered in aerosol–cloud interactions. Our results could help to decease uncertainties in climate models.
Bernadette Rosati, Sini Isokääntä, Sigurd Christiansen, Mads Mørk Jensen, Shamjad P. Moosakutty, Robin Wollesen de Jonge, Andreas Massling, Marianne Glasius, Jonas Elm, Annele Virtanen, and Merete Bilde
Atmos. Chem. Phys., 22, 13449–13466, https://doi.org/10.5194/acp-22-13449-2022, https://doi.org/10.5194/acp-22-13449-2022, 2022
Short summary
Short summary
Sulfate aerosols have a strong influence on climate. Due to the reduction in sulfur-based fossil fuels, natural sulfur emissions play an increasingly important role. Studies investigating the climate relevance of natural sulfur aerosols are scarce. We study the water uptake of such particles in the laboratory, demonstrating a high potential to take up water and form cloud droplets. During atmospheric transit, chemical processing affects the particles’ composition and thus their water uptake.
Kanishk Gohil, Chun-Ning Mao, Dewansh Rastogi, Chao Peng, Mingjin Tang, and Akua Asa-Awuku
Atmos. Chem. Phys., 22, 12769–12787, https://doi.org/10.5194/acp-22-12769-2022, https://doi.org/10.5194/acp-22-12769-2022, 2022
Short summary
Short summary
The Hybrid Activity Model (HAM) is a promising new droplet growth model that can be potentially used for the analysis of any type of atmospheric compound. HAM may potentially improve the representation of hygroscopicity of organic aerosols in large-scale global climate models (GCMs), hence reducing the uncertainties in the climate forcing due to the aerosol indirect effect.
Charbel Harb and Hosein Foroutan
Atmos. Chem. Phys., 22, 11759–11779, https://doi.org/10.5194/acp-22-11759-2022, https://doi.org/10.5194/acp-22-11759-2022, 2022
Short summary
Short summary
A model representation of lake spray aerosol (LSA) ejection from freshwater breaking waves is crucial for understanding their climatic and public health impacts. We develop an LSA emission parameterization and implement it in an atmospheric model to investigate Great Lakes surface emissions. We find that the same breaking wave is likely to produce fewer aerosols in freshwater than in saltwater and that Great Lakes emissions influence the regional aerosol burden and can reach the cloud layer.
Runlong Cai, Ella Häkkinen, Chao Yan, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 11529–11541, https://doi.org/10.5194/acp-22-11529-2022, https://doi.org/10.5194/acp-22-11529-2022, 2022
Short summary
Short summary
The influences of new particle formation on the climate and air quality are governed by particle survival, which has been under debate due to uncertainties in the coagulation sink. Here we measure the coagulation coefficient of sub-10 nm particles and demonstrate that collisions between the freshly nucleated and background particles can effectively lead to coagulation. We further show that the effective coagulation sink is consistent with the new particle formation measured in urban Beijing.
Lamei Shi, Jiahua Zhang, Da Zhang, Jingwen Wang, Xianglei Meng, Yuqin Liu, and Fengmei Yao
Atmos. Chem. Phys., 22, 11255–11274, https://doi.org/10.5194/acp-22-11255-2022, https://doi.org/10.5194/acp-22-11255-2022, 2022
Short summary
Short summary
Dust impacts climate and human life. Analyzing the interdecadal change in dust activity and its influence factors is crucial for disaster mitigation. Based on a linear regression method, this study revealed the interdecadal variability of relationships between ENSO and dust over northwestern South Asia from 1982 to 2014 and analyzed the effects of atmospheric factors on this interdecadal variability. The result sheds new light on numerical simulation involving the interdecadal variation of dust.
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
Short summary
Short summary
In this study, the viscosities of particles of sucrose–H2O, AS–H2O, and sucrose–AS–H2O for OIRs of 4:1, 1:1, and 1:4 for decreasing RH, were quantified by poke-and-flow and bead-mobility techniques at 293 ± 1 K. Based on the viscosity results, the particles of binary and ternary systems ranged from liquid to semisolid, and even the solid state depending on the RH. Moreover, we compared the measured viscosities of ternary systems to the predicted viscosities with excellent agreement.
Minxia Shen, Kin Fai Ho, Wenting Dai, Suixin Liu, Ting Zhang, Qiyuan Wang, Jingjing Meng, Judith C. Chow, John G. Watson, Junji Cao, and Jianjun Li
Atmos. Chem. Phys., 22, 7489–7504, https://doi.org/10.5194/acp-22-7489-2022, https://doi.org/10.5194/acp-22-7489-2022, 2022
Short summary
Short summary
Looking at characteristics and δ13C compositions of dicarboxylic acids and related compounds in BB aerosols, we used a combined combustion and aging system to generate fresh and aged aerosols from burning straw. The results showed the emission factors (EFaged) of total diacids of aging experiments were around an order of magnitude higher than EFfresh. This meant that dicarboxylic acids are involved with secondary photochemical processes in the atmosphere rather than primary emissions from BB.
Jonas K. F. Jakobsson, Deepak B. Waman, Vaughan T. J. Phillips, and Thomas Bjerring Kristensen
Atmos. Chem. Phys., 22, 6717–6748, https://doi.org/10.5194/acp-22-6717-2022, https://doi.org/10.5194/acp-22-6717-2022, 2022
Short summary
Short summary
Long-lived cold-layer clouds at subzero temperatures are observed to be remarkably persistent in their generation of ice particles and snow precipitation. There is uncertainty about why this is so. This motivates the present lab study to observe the long-term ice-nucleating ability of aerosol samples from the real troposphere. Time dependence of their ice nucleation is observed to be weak in lab experiments exposing the samples to isothermal conditions for up to about 10 h.
Kunfeng Gao, Chong-Wen Zhou, Eszter J. Barthazy Meier, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 5331–5364, https://doi.org/10.5194/acp-22-5331-2022, https://doi.org/10.5194/acp-22-5331-2022, 2022
Short summary
Short summary
Incomplete combustion of fossil fuel produces carbonaceous particles called soot. These particles can affect cloud formation by acting as centres for droplet or ice formation. The atmospheric residence time of soot particles is of the order of days to weeks, which can result in them becoming coated by various trace species in the atmosphere such as acids. In this study, we quantify the cirrus cloud-forming ability of soot particles coated with the atmospherically ubiquitous sulfuric acid.
Kunfeng Gao, Franz Friebel, Chong-Wen Zhou, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 4985–5016, https://doi.org/10.5194/acp-22-4985-2022, https://doi.org/10.5194/acp-22-4985-2022, 2022
Short summary
Short summary
Soot particles impact cloud formation and radiative properties in the upper atmosphere where aircraft emit carbonaceous particles. We use cloud chambers to mimic the upper atmosphere temperature and humidity to test the influence of the morphology of the soot particles on ice cloud formation. For particles larger than 200 nm, the compacted (densified) samples have a higher affinity for ice crystal formation in the cirrus regime than the fluffy (un-compacted) soot particles of the same sample.
Joel Kuula, Hilkka Timonen, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Tareq Hussein, Pak Lun Fung, Sasu Tarkoma, Mikko Laakso, Erkka Saukko, Aino Ovaska, Markku Kulmala, Ari Karppinen, Lasse Johansson, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 4801–4808, https://doi.org/10.5194/acp-22-4801-2022, https://doi.org/10.5194/acp-22-4801-2022, 2022
Short summary
Short summary
Modern and up-to-date policies and air quality management strategies are instrumental in tackling global air pollution. As the European Union is preparing to revise Ambient Air Quality Directive 2008/50/EC, this paper initiates discussion on selected features of the directive that we believe would benefit from a reassessment. The scientific community has the most recent and deepest understanding of air pollution; thus, its contribution is essential.
Yu Wang, Aristeidis Voliotis, Dawei Hu, Yunqi Shao, Mao Du, Ying Chen, Judith Kleinheins, Claudia Marcolli, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 4149–4166, https://doi.org/10.5194/acp-22-4149-2022, https://doi.org/10.5194/acp-22-4149-2022, 2022
Short summary
Short summary
Aerosol water uptake plays a key role in atmospheric physicochemical processes. We designed chamber experiments on aerosol water uptake of secondary organic aerosol (SOA) from mixed biogenic and anthropogenic precursors with inorganic seed. Our results highlight this chemical composition influences the reconciliation of the sub- and super-saturated water uptake, providing laboratory evidence for understanding the chemical controls of water uptake of the multi-component aerosol.
Shuang Han, Juan Hong, Qingwei Luo, Hanbing Xu, Haobo Tan, Qiaoqiao Wang, Jiangchuan Tao, Yaqing Zhou, Long Peng, Yao He, Jingnan Shi, Nan Ma, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 3985–4004, https://doi.org/10.5194/acp-22-3985-2022, https://doi.org/10.5194/acp-22-3985-2022, 2022
Short summary
Short summary
We present the hygroscopicity of 23 organic species with different physicochemical properties using a hygroscopicity tandem differential mobility analyzer (HTDMA) and compare the results with previous studies. Based on the hygroscopicity parameter κ, the influence of different physicochemical properties that potentially drive hygroscopicity, such as the functionality, water solubility, molar volume, and O : C ratio of organics, are examined separately.
Kimmo Korhonen, Thomas Bjerring Kristensen, John Falk, Vilhelm B. Malmborg, Axel Eriksson, Louise Gren, Maja Novakovic, Sam Shamun, Panu Karjalainen, Lassi Markkula, Joakim Pagels, Birgitta Svenningsson, Martin Tunér, Mika Komppula, Ari Laaksonen, and Annele Virtanen
Atmos. Chem. Phys., 22, 1615–1631, https://doi.org/10.5194/acp-22-1615-2022, https://doi.org/10.5194/acp-22-1615-2022, 2022
Short summary
Short summary
We investigated the ice-nucleating abilities of particulate emissions from a modern diesel engine using the portable ice-nuclei counter SPIN, a continuous-flow diffusion chamber instrument. Three different fuels were studied without blending, including fossil diesel and two renewable fuels, testing different emission aftertreatment systems and photochemical aging. We found that the diesel emissions were inefficient ice nuclei, and aging had no or little effect on their ice-nucleating abilities.
Noora Hyttinen, Iida Pullinen, Aki Nissinen, Siegfried Schobesberger, Annele Virtanen, and Taina Yli-Juuti
Atmos. Chem. Phys., 22, 1195–1208, https://doi.org/10.5194/acp-22-1195-2022, https://doi.org/10.5194/acp-22-1195-2022, 2022
Short summary
Short summary
Accurate saturation vapor pressure estimates of atmospherically relevant organic compounds are critical for modeling secondary organic aerosol (SOA) formation. We investigated vapor pressures of highly oxygenated SOA constituents using state-of-the-art computational and experimental methods. We found a good agreement between low and extremely low vapor pressures estimated using the two methods, and the smallest molecules detected in our experiment were likely products of thermal decomposition.
Dawei Hu, M. Rami Alfarra, Kate Szpek, Justin M. Langridge, Michael I. Cotterell, Claire Belcher, Ian Rule, Zixia Liu, Chenjie Yu, Yunqi Shao, Aristeidis Voliotis, Mao Du, Brett Smith, Greg Smallwood, Prem Lobo, Dantong Liu, Jim M. Haywood, Hugh Coe, and James D. Allan
Atmos. Chem. Phys., 21, 16161–16182, https://doi.org/10.5194/acp-21-16161-2021, https://doi.org/10.5194/acp-21-16161-2021, 2021
Short summary
Short summary
Here, we developed new techniques for investigating these properties in the laboratory and applied these to BC and BrC from different sources, including diesel exhaust, inverted propane flame and wood combustion. These have allowed us to quantify the changes in shape and chemical composition of different soots according to source and variables such as the moisture content of wood.
Mariam Fawaz, Anita Avery, Timothy B. Onasch, Leah R. Williams, and Tami C. Bond
Atmos. Chem. Phys., 21, 15605–15618, https://doi.org/10.5194/acp-21-15605-2021, https://doi.org/10.5194/acp-21-15605-2021, 2021
Short summary
Short summary
Biomass burning is responsible for 90 % of the emissions of primary organic aerosols to the atmosphere. Emissions from biomass burning sources are considered chaotic. In this work, we developed a controlled experimental approach to understand the controlling factors in emission. Our results showed that emissions are repeatable and deterministic and that emissions from wood can be constrained.
Soleil E. Worthy, Anand Kumar, Yu Xi, Jingwei Yun, Jessie Chen, Cuishan Xu, Victoria E. Irish, Pierre Amato, and Allan K. Bertram
Atmos. Chem. Phys., 21, 14631–14648, https://doi.org/10.5194/acp-21-14631-2021, https://doi.org/10.5194/acp-21-14631-2021, 2021
Short summary
Short summary
We studied the effect of (NH4)2SO4 on the immersion freezing of non-mineral dust ice-nucleating substances (INSs) and mineral dusts. (NH4)2SO4 had no effect on the median freezing temperature of 9 of the 10 tested non-mineral dust INSs, slightly decreased that of the other, and increased that of all the mineral dusts. The difference in the response of mineral dust and non-mineral dust INSs to (NH4)2SO4 suggests that they nucleate ice and/or interact with (NH4)2SO4 via different mechanisms.
Robert Wagner, Luisa Ickes, Allan K. Bertram, Nora Els, Elena Gorokhova, Ottmar Möhler, Benjamin J. Murray, Nsikanabasi Silas Umo, and Matthew E. Salter
Atmos. Chem. Phys., 21, 13903–13930, https://doi.org/10.5194/acp-21-13903-2021, https://doi.org/10.5194/acp-21-13903-2021, 2021
Short summary
Short summary
Sea spray aerosol particles are a mixture of inorganic salts and organic matter from phytoplankton organisms. At low temperatures in the upper troposphere, both inorganic and organic constituents can induce the formation of ice crystals and thereby impact cloud properties and climate. In this study, we performed experiments in a cloud simulation chamber with particles produced from Arctic seawater samples to quantify the relative contribution of inorganic and organic species in ice formation.
Matthew Ozon, Dominik Stolzenburg, Lubna Dada, Aku Seppänen, and Kari E. J. Lehtinen
Atmos. Chem. Phys., 21, 12595–12611, https://doi.org/10.5194/acp-21-12595-2021, https://doi.org/10.5194/acp-21-12595-2021, 2021
Short summary
Short summary
Measuring the rate at which aerosol particles are formed is of importance for understanding climate change. We present an analysis method based on Kalman smoothing, which retrieves new particle formation and growth rates from size-distribution measurements. We apply it to atmospheric simulation chamber experiments and show that it agrees well with traditional methods. In addition, it provides reliable uncertainty estimates, and we suggest instrument design optimisation for signal processing.
Cited articles
Allan, J. D., Baumgardner, D., Raga, G. B., Mayol-Bracero, O. L.,
Morales-García, F., García-García, F., Montero-Martínez,
G., Borrmann, S., Schneider, J., Mertes, S., Walter, S., Gysel, M., Dusek,
U., Frank, G. P., and Krämer, M.: Clouds and aerosols in Puerto Rico – A
new evaluation, Atmos. Chem. Phys., 8, 1293–1309,
https://doi.org/10.5194/acp-8-1293-2008, 2008.
Baumgardner, D., Raga, G. B., and Muhlia, A.: Evidence for the formation of
CCN by photochemical processes in Mexico City, Atmos. Environ., 38,
357–367, https://doi.org/10.1016/j.atmosenv.2003.10.008, 2004.
Calvo, A. I., Baumgardner, D., Castro, A., Fernández-González, D.,
Vega-Maray, A. M., Valencia-Barrera, R. M., Oduber, F., Blanco-Alegre, C.,
and Fraile, R.: Daily behavior of urban Fluorescing Aerosol Particles in
northwest Spain, Atmos. Environ., 184, 267–277,
https://doi.org/10.1016/j.atmosenv.2018.04.027, 2018.
Caulton, E. and Lacey, M.: Airborne Pollens and Spores. A Guide to Trapping and
Counting, 1st Edn., Harpenden, British Aerobiology Federation, ISBN 0952561700, 1995.
Chi, M. C. and Li, C. S.: Fluorochrome in monitoring atmospheric bioaerosols
and correlations with meteorological factors and air pollutants, Aerosol
Sci. Technol., 41, 672–678, https://doi.org/10.1080/02786820701383181, 2007.
Duan, J., Chen, Y., and Guo, X.: Characteristics of aerosol activation
efficiency and aerosol and CCN vertical distributions in North China, Acta
Meteorol. Sin., 26, 579–596, https://doi.org/10.1007/s13351-012-0504-6, 2012.
Fennelly, M. J., Sewell, G., Prentice, M. B., O'Connor, D. J., and Sodeau,
J. R.: The Use of Real-Time Fluorescence Instrumentation to Monitor Ambient
Primary Biological Aerosol Particles (PBAP), Atmosphere, 9, 1–39,
https://doi.org/10.3390/atmos9010001, 2017.
Fröhlich-Nowoisky, J., Kampf, C. J., Weber, B., Huffman, J. A.,
Pöhlker, C., Andreae, M. O., Lang-Yona, N., Burrows, S. M., Gunthe, S.
S., Elbert, W., Su, H., Hoor, P., Thines, E., Hoffmann, T., Després, V.
R., and Pöschl, U.: Bioaerosols in the Earth system: Climate, health, and
ecosystem interactions, Atmos. Res., 182, 346–376,
https://doi.org/10.1016/j.atmosres.2016.07.018, 2016.
Gabey, A. M.: Laboratory and field characterization of fluorescent and
primary biological aerosol particles, Ph.D. thesis, University of
Manchester, England, 2011.
Gabey, A. M., Gallagher, M. W., Whitehead, J., Dorsey, J. R., Kaye, P. H.,
and Stanley, W. R.: Measurements and comparison of primary biological
aerosol above and below a tropical forest canopy using a dual channel
fluorescence spectrometer, Atmos. Chem. Phys., 10, 4453–4466,
https://doi.org/10.5194/acp-10-4453-2010, 2010.
Gabey, A. M., Vaitilingom, M., Freney, E., Boulon, J., Sellegri, K.,
Gallagher, M. W., Crawford, I. P., Robinson, N. H., Stanley, W. R., and
Kaye, P. H.: Observations of fluorescent and biological aerosol at a
high-altitude site in central France, Atmos. Chem. Phys., 13, 7415–7428,
https://doi.org/10.5194/acp-13-7415-2013, 2013.
Gioda, A., Mayol-Bracero, O. L., Scatena, F. N., Weathers, K. C., Mateus, V.
L., and McDowell, W. H.: Chemical constituents in clouds and rainwater in the
Puerto Rican rainforest: Potential sources and seasonal drivers, Atmos.
Environ., 68, 208–220, https://doi.org/10.1016/j.atmosenv.2012.11.017, 2013.
Gosselin, M. I., Rathnayake, C. M., Crawford, I., Pöhlker, C.,
Fröhlich-Nowoisky, J., Schmer, B., Després, V. R., Engling, G.,
Gallagher, M., Stone, E., Pöschl, U., and Huffman, J. A.: Fluorescent
bioaerosol particle, molecular tracer, and fungal spore concentrations
during dry and rainy periods in a semi-arid forest, Atmos. Chem. Phys., 16,
15165–15184, https://doi.org/10.5194/acp-16-15165-2016, 2016.
Healy, D. A., Huffman, J. A., O'Connor, D. J., Pöhlker, C., Pöschl,
U., and Sodeau, J. R.: Ambient measurements of biological aerosol particles
near Killarney, Ireland: a comparison between real-time fluorescence and
microscopy techniques, Atmos. Chem. Phys., 14, 8055–8069,
https://doi.org/10.5194/acp-14-8055-2014, 2014.
Hernandez, M., Perring, A. E., McCabe, K., Kok, G., Granger, G., and
Baumgardner, D.: Chamber catalogues of optical and fluorescent signatures
distinguish bioaerosol classes, Atmos. Meas. Tech., 9, 3283–3292,
https://doi.org/10.5194/amt-9-3283-2016, 2016.
Ho, J., Spence, M., and Hairston, P.: Measurement of Biological Aerosol with
a Fluorescent Aerodynamic Particle Sizer (FLAPS): Correlation of Optical
Data with Biological Data, Aerobiologia, 15, 281–291,
https://doi.org/10.1023/A:1007647522397, 1999.
Hoose, C., Kristjánsson, J. E., and Burrows, S. M.: How important is
biological ice nucleation in clouds on a global scale?, Environ. Res. Lett.,
5, 024009, https://doi.org/10.1088/1748-9326/5/2/024009, 2010.
Huffman, J. A. and Santarpia, J. L.: Online techniques for quantification and
characterization of biological aerosol, in: Microbiology of Aerosols, edited
by: Delort, A. M. and Amato, P., Wiley, Hoboken, NJ, chap. 1.4, John Wiley & Sons, Inc., New York, https://doi.org/10.1002/9781119132318.ch1d, 2017.
Jaenicke, R.: Abundance of cellular material and proteins in the atmosphere,
Science, 308, p. 73, https://doi.org/10.1126/science.1106335, 2005.
Kaye, P. H., Stanley, W. R., Hirst, E., Foot, E. V., Baxter, K. L., and
Barrington, S. J.: Single particle multichannel bio-aerosol fluorescence
sensor, Opt. Express, 13, 3583–3593, 2005.
Kaye, P. H., Aptowicz, K., Chang, R. K., Foot, V., and Videen, G.: Angularly
resolved elastic scattering from airborne particles – Potential for
characterizing, classifying, and identifying individual aerosol particles,
Opt. Biol. Part., 238, 31–61, 2007.
Kulkarni, P., Baron, P. A., and Willeke, K.: Aerosol Measurement: Principles,
Techniques, and Applications, 3rd Edn., Wiley, ISBN 978-0-470-38741-2, 2011.
Möhler, O., DeMott,
P. J., Vali, G., and Levin, Z.: Microbiology and atmospheric processes: the
role of biological particles in cloud physics, Biogeosciences, 4,
1059–1071, https://doi.org/10.5194/bg-4-1059-2007, 2007.
Oliveira, M., Ribeiro, H., and Abreu, I.: Annual variation of fungal spores
in atmosphere of Porto: 2003, Ann. Agric. Environ. Med., 12, 309–315,
2005.
Ortiz-Martínez, M. G., Rodríguez-Cotto, R. I., Ortiz-Rivera, M.
A., Pluguez-Turull, C. W., and Jiménez-Vélez, B. D.: Linking
Endotoxins, African Dust PM10 and Asthma in an Urban and Rural
Environment of Puerto Rico, Mediators Inflamm., 2015, 784212,
https://doi.org/10.1155/2015/784212, 2015.
Perring, A. E., Schwarz, J. P., Baumgardner, D., Hernandez, M. T.,
Spracklen, D. V., Heald, C. L., Gao, R. S., Kok, G., McMeeking, G. R.,
McQuaid, J. B., and Fahey, D. W.: Airborne observations of regional
variation in fluorescent aerosol across the United States, J. Geophys.
Res.-Atmos., 120, 1153–1170, https://doi.org/10.1002/2014JD022495, 2015.
Pope, F. D.: Pollen grains are efficient cloud condensation nuclei, Environ.
Res. Lett., 5, 044015, https://doi.org/10.1088/17489326/5/4/044015, 2010.
Quintero, E., Rivera-Mariani, F., and Bolaños-Rosero, B.: Analysis of
environmental factors and their effects on fungal spores in the atmosphere
of a tropical urban area (San Juan, Puerto Rico), Aerobiologia,
26, 113–124, https://doi.org/10.1007/s10453-009-9148-0, 2010.
Raga, G. B., Baumgardner, D., and Mayol-Bracero, O. L.: History of
aerosol-cloud interactions derived from observations in mountaintop clouds
in Puerto Rico, Aerosol Air Qual. Res., 16, 674–688,
https://doi.org/10.4209/aaqr.2015.05.0359, 2016.
Roberts, G. C. and Nenes, A.: A Continuous-Flow Streamwise Thermal-Gradient
CCN Chamber for Atmospheric Measurements, Aerosol Sci. Technol., 39,
206–221, 2005.
Rivera-Mariani, F. E., Nazario-Jiménez, S., López-Malpica, F., and
Bolaños-Rosero, B.: Sensitization to airborne ascospores, basidiospores,
and fungal fragments in allergic rhinitis and asthmatic subjects in San
Juan, Puerto Rico, Int. Arch. Allergy Immunol., 155, 322–334,
https://doi.org/10.1159/000321610, 2011.
Rivera-Mariani, F. E., Almaguer, M., Aira, M. J., and Bolaños-Rosero, B.:
Comparison of atmospheric fungal spore concentrations between two main
cities in the Caribbean basin, P. R. Health Sci. J., 39, 235–242, 2020.
Sarangi, B., Baumgardner, D., Bolaños-Rosero, B., and Mayol-Bracero, O.
L.: Dataset to: Measurement Report: An Exploratory Study of Fluorescence and
CCN Activity of Urban Aerosols in San Juan, Puerto Rico, Mendeley Data [data set],
Version 1, https://doi.org/10.17632/t26dctfk7t.1, 2021.
Savage, N. J., Krentz, C. E., Könemann, T., Han, T. T., Mainelis, G.,
Pöhlker, C., and Alex Huffman, J.: Systematic characterization and
fluorescence threshold strategies for the wideband integrated bioaerosol
sensor (WIBS) using size-resolved biological and interfering particles,
Atmos. Meas. Tech., 10, 4279–4302, https://doi.org/10.5194/amt-10-4279-2017, 2017.
Spiegel, J. K., Buchmann, N., Mayol-Bracero, O. L., Cuadra-Rodriguez, L. A.,
Valle Díaz, C. J., Prather, K. A., Mertes, S., and Eugster, W.: Do Cloud
Properties in a Puerto Rican Tropical Montane Cloud Forest Depend on
Occurrence of Long-Range Transported African Dust?, Pure Appl. Geophys.,
171, 2443–2459, https://doi.org/10.1007/s00024-014-0830-y, 2014.
Stanley, W. R., Kaye, P. H., Foot, V. E., Barrington, S. J., Gallagher, M.,
and Gabey, A.: Continuous bioaerosol monitoring in a tropical environment
using a UV fluorescence particle spectrometer, Atmos. Sci. Lett., 12,
195–199, https://doi.org/10.1002/asl.310, 2011.
Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M., Allen, S. K., Boschung,
J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M.: Climate
change 2013: the physical science basis, Contribution of working group I to
the fifth assessment report of the intergovernmental panel on climate
change, IPCC, 2013, Cambridge University Press, Cambridge, United Kingdom
and New York, NY, USA, p. 1535, edited by: Stommel, E. W., Fiel, ISBN 978-1-107-05799-1, 2013.
Stolzenburg, M. R. and McMurry, P. H.: An Ultrafine Aerosol Condensation
Nucleus Counter, Aerosol Sci. Tech., 14, 48–65, 1991.
Toprak, E. and Schnaiter, M.: Fluorescent biological aerosol particles
measured with the Waveband Integrated Bioaerosol Sensor WIBS-4: laboratory
tests combined with a one year field study, Atmos. Chem. Phys., 13,
225–243, https://doi.org/10.5194/acp-13-225-2013, 2013.
Torres-Delgado, E., Baumgardner, D., and Mayol-Bracero, O. L.: Measurement report: Impact of African aerosol particles on cloud evolution in a tropical montane cloud forest in the Caribbean, Atmos. Chem. Phys., 21, 18011–18027, https://doi.org/10.5194/acp-21-18011-2021, 2021.
Toro-Heredia, J., Jirau-Colón, H., and Jiménez-Vélez, B. D.:
Linking PM2.5 organic constituents, relative toxicity and health effects in
Puerto Rico, Environ. Chall., 5, 100350, https://doi.org/10.1016/j.envc.2021.100350,
2021.
Twohy, C. H., McMeeking, G. R., DeMott, P. J., McCluskey, C. S., Hill, T. C.
J., Burrows, S. M., Kulkarni, G. R., Tanarhte, M., Kafle, D. N., and Toohey,
D. W.: Abundance of fluorescent biological aerosol particles at temperatures
conducive to the formation of mixed-phase and cirrus clouds, Atmos. Chem.
Phys., 16, 8205–8225, https://doi.org/10.5194/acp-16-8205-2016, 2016.
Valle-Díaz, C. J., Torres-Delgado, E., Colón-Santos, S. M., Lee,
T., Collett, J. L., McDowell, W. H., and Mayol-Bracero, O. L.: Impact of
long-range transported african dust on cloud water chemistry at a tropical
montane cloud forest in Northeastern Puerto Rico, Aerosol Air Qual.
Res., 16, 653–664, https://doi.org/10.4209/aaqr.2015.05.0320,
2016.
Velázquez-Lozada, A., González, J. E., and Winter, A.:
Urban heat islands effect analysis for San Juan, Puerto Rico, Atmos.
Environ., 40, 1731–1741, 2006.
Whitehead, J. D., Darbyshire, E., Brito, J., Barbosa, H. M. J., Crawford, I., Stern, R., Gallagher, M. W., Kaye, P. H., Allan, J. D.,
Coe, H., Artaxo, P., and McFiggans, G.: Biogenic cloud nuclei in the central Amazon during the transition from wet to dry season,
Atmos. Chem. Phys., 16, 9727–9743, https://doi.org/10.5194/acp-16-9727-2016, 2016.
Uin, J.: Ultra-High Sensitivity Aerosol Spectrometer (UHSAS) instrument
handbook, ARM Tech. Rep. DOE/SCARM-TR-163, USA, 17 pp., U.S. Department of Energy,
doi.org/10.2172/1251410, 2016.
Zhang, M., Khaled, A., Amato, P., Delort, A.-M., and Ervens, B.:
Sensitivities to biological aerosol particle properties and ageing
processes: potential implications for aerosol–cloud interactions and
optical properties, Atmos. Chem. Phys., 21, 3699–3724,
https://doi.org/10.5194/acp-21-3699-2021, 2021.
Ziemba, L. D., Beyersdorf, A. J., Chen, G., Corr, C. A., Crumeyrolle, S. N., Diskin, G., Hudgins, C., Martin, R., Mikoviny, T.,
Moore, R., Shook, M., Lee Thornhill, K., Winstead, E. L., Wisthaler, A., and Anderson, B. E.: Airborne observations of bioaerosol
over the Southeast United States using a Wideband Integrated Bioaerosol Sensor, J. Geophys. Res., 121, 8506–8524,
https://doi.org/10.1002/2015JD024669, 2016.
Short summary
Here, the fluorescent characteristics and cloud-forming efficiency of aerosols at an urban site in Puerto Rico are discussed. The results from this pilot study highlight the capabilities of ultraviolet-induced fluorescence (UV-IF) measurements for characterizing the properties of fluorescing aerosol particles, as they relate to the daily evolution of primary biological aerosol particles. This work has established a database of measurements on which future, longer-term studies will be initiated.
Here, the fluorescent characteristics and cloud-forming efficiency of aerosols at an urban site...
Altmetrics
Final-revised paper
Preprint