Articles | Volume 14, issue 10
Atmos. Chem. Phys., 14, 5217–5231, 2014
https://doi.org/10.5194/acp-14-5217-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Atmos. Chem. Phys., 14, 5217–5231, 2014
https://doi.org/10.5194/acp-14-5217-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article 27 May 2014
Research article | 27 May 2014
Ground-based measurements of immersion freezing in the eastern Mediterranean
K. Ardon-Dryer and Z. Levin
Related authors
K. Ardon-Dryer, Y.-W. Huang, and D. J. Cziczo
Atmos. Chem. Phys., 15, 9159–9171, https://doi.org/10.5194/acp-15-9159-2015, https://doi.org/10.5194/acp-15-9159-2015, 2015
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The collection between aerosol and a water droplet is an important mechanism for removing particles from the atmosphere, and has an influence on cloud dynamics, precipitation processes and cloud lifetime. In this experiment, the collection process was studied on a single-droplet basis, with atmospherically relevant conditions (droplet sizes, charges and flow). Collection efficiency values were found to be in agreement with previous experimental and theoretical studies.
K. Ardon-Dryer, Y.-W. Huang, and D. J. Cziczo
Atmos. Chem. Phys., 15, 9159–9171, https://doi.org/10.5194/acp-15-9159-2015, https://doi.org/10.5194/acp-15-9159-2015, 2015
Short summary
Short summary
The collection between aerosol and a water droplet is an important mechanism for removing particles from the atmosphere, and has an influence on cloud dynamics, precipitation processes and cloud lifetime. In this experiment, the collection process was studied on a single-droplet basis, with atmospherically relevant conditions (droplet sizes, charges and flow). Collection efficiency values were found to be in agreement with previous experimental and theoretical studies.
M. Abdelkader, S. Metzger, R. E. Mamouri, M. Astitha, L. Barrie, Z. Levin, and J. Lelieveld
Atmos. Chem. Phys., 15, 9173–9189, https://doi.org/10.5194/acp-15-9173-2015, https://doi.org/10.5194/acp-15-9173-2015, 2015
E. Tas, A. Teller, O. Altaratz, D. Axisa, R. Bruintjes, Z. Levin, and I. Koren
Atmos. Chem. Phys., 15, 2009–2017, https://doi.org/10.5194/acp-15-2009-2015, https://doi.org/10.5194/acp-15-2009-2015, 2015
E. Hirsch, I. Koren, Z. Levin, O. Altaratz, and E. Agassi
Atmos. Chem. Phys., 14, 9001–9012, https://doi.org/10.5194/acp-14-9001-2014, https://doi.org/10.5194/acp-14-9001-2014, 2014
E. Hirsch, I. Koren, O. Altaratz, Z. Levin, and E. Agassi
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-28729-2013, https://doi.org/10.5194/acpd-13-28729-2013, 2013
Revised manuscript not accepted
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Aerosol particle formation in the upper residual layer
Secondary aerosol formation alters CCN activity in the North China Plain
Complex refractive indices in the ultraviolet and visible spectral region for highly absorbing non-spherical biomass burning aerosol
Dilution impacts on smoke aging: evidence in Biomass Burning Observation Project (BBOP) data
Measurement report: Balloon-borne in situ profiling of Saharan dust over Cyprus with the UCASS optical particle counter
El Niño–Southern Oscillation (ENSO) effect on interannual variability in spring aerosols over East Asia
The impact threshold of the aerosol radiative forcing on the boundary layer structure in the pollution region
Technical note: Measurement of chemically resolved volume equivalent diameter and effective density of particles by AAC-SPAMS
The impact of cloudiness and cloud type on the atmospheric heating rate of black and brown carbon in the Po Valley
Meteorology-driven variability of air pollution (PM1) revealed with explainable machine learning
The seasonal cycle of ice-nucleating particles linked to the abundance of biogenic aerosol in boreal forests
Technical note: sea salt interference with black carbon quantification in snow samples using the single particle soot photometer
Measurement report: Cloud processes and the transport of biological emissions affect southern ocean particle and cloud condensation nuclei concentrations
Effects of marine fuel sulfur restrictions on particle number concentrations and size distributions in ship plumes in the Baltic Sea
Elemental and water-insoluble organic carbon in Svalbard snow: a synthesis of observations during 2007–2018
Deposition of light-absorbing particles in glacier snow of the Sunderdhunga Valley, the southern forefront of the central Himalayas
Influence of vegetation on occurrence and time distributions of regional new aerosol particle formation and growth
Dominant synoptic patterns associated with the decay process of PM2.5 pollution episodes around Beijing
Validation of aerosol backscatter profiles from Raman lidar and ceilometer using balloon-borne measurements
Impacts of coagulation on the appearance time method for new particle growth rate evaluation and their corrections
PM2.5 surface concentrations in southern West African urban areas based on sun photometer and satellite observations
Observations on aerosol optical properties and scavenging during cloud events
Assessing the vertical structure of Arctic aerosols using balloon-borne measurements
The impact of aerosol size-dependent hygroscopicity and mixing state on the cloud condensation nuclei potential over the Northeast Atlantic
An overview of the ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) project: aerosol–cloud–radiation interactions in the southeast Atlantic basin
Measurement report: aerosol hygroscopic properties extended to 600 nm in the urban environment
Rapid transformation of ambient absorbing aerosols from West African biomass burning
Spatiotemporal variation and trends in equivalent black carbon in the Helsinki metropolitan area in Finland
Characteristics of sub-10 nm particle emissions from in-use commercial aircraft observed at Narita International Airport
The CLoud–Aerosol–Radiation Interaction and Forcing: Year 2017 (CLARIFY-2017) measurement campaign
Measurement report: quantifying source contribution of fossil fuels and biomass-burning black carbon aerosol in the southeastern margin of the Tibetan Plateau
The electrical activity of Saharan dust as perceived from surface electric field observations
Long-term measurement of sub-3 nm particles and their precursor gases in the boreal forest
Variability in the mass absorption cross section of black carbon (BC) aerosols is driven by BC internal mixing state at a central European background site (Melpitz, Germany) in winter
Optical and hygroscopic properties of black carbon influenced by particle microphysics at the top of the anthropogenically polluted boundary layer
Measurement report: The effect of aerosol chemical composition on light scattering due to the hygroscopic swelling effect
Measurement report: Properties of aerosol and gases in the vertical profile during the LAPSE-RATE campaign
Aircraft vertical profiles during summertime regional and Saharan dust scenarios over the north-western Mediterranean basin: aerosol optical and physical properties
African dust particles over the western Caribbean – Part I: Impact on air quality over the Yucatán Peninsula
Direct measurements of black carbon fluxes in central Beijing using the eddy covariance method
Measurement report: Altitudinal variation of CCN activation across the Indo-Gangetic Plains prior to monsoon onset and during peak monsoon periods: Results from the SWAAMI field campaign
Measurements to determine the mixing state of black carbon emitted from the 2017–2018 California wildfires and urban Los Angeles
What can we learn about urban air quality with regard to the first outbreak of the COVID-19 pandemic? A case study from central Europe
The important roles of surface tension and growth rate in the contribution of new particle formation (NPF) to cloud condensation nuclei (CCN) number concentration: evidence from field measurements in southern China
Measurement report: Source and mixing state of black carbon aerosol in the North China Plain: implications for radiative effect
The potential role of organics in new particle formation and initial growth in the remote tropical upper troposphere
Impacts of long-range transport of aerosols on marine-boundary-layer clouds in the eastern North Atlantic
Strong Light Absorption Induced by Aged Biomass Burning Black Carbon over the Southeastern Tibetan Plateau in Pre-monsoon Season
On the drivers of droplet variability in Alpine mixed-phase clouds
Quantifying bioaerosol concentrations in dust clouds through online UV-LIF and mass spectrometry measurements at the Cape Verde Atmospheric Observatory
Janne Lampilahti, Katri Leino, Antti Manninen, Pyry Poutanen, Anna Franck, Maija Peltola, Paula Hietala, Lisa Beck, Lubna Dada, Lauriane Quéléver, Ronja Öhrnberg, Ying Zhou, Madeleine Ekblom, Ville Vakkari, Sergej Zilitinkevich, Veli-Matti Kerminen, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 7901–7915, https://doi.org/10.5194/acp-21-7901-2021, https://doi.org/10.5194/acp-21-7901-2021, 2021
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Using airborne measurements we observed increased number concentrations of sub-25 nm particles in the upper residual layer. These particles may be entrained into the well-mixed boundary layer and observed at the surface. We attribute our observations to new particle formation in the topmost part of the residual layer.
Jiangchuan Tao, Ye Kuang, Nan Ma, Juan Hong, Yele Sun, Wanyun Xu, Yanyan Zhang, Yao He, Qingwei Luo, Linhong Xie, Hang Su, and Yafang Cheng
Atmos. Chem. Phys., 21, 7409–7427, https://doi.org/10.5194/acp-21-7409-2021, https://doi.org/10.5194/acp-21-7409-2021, 2021
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The mechanism of secondary aerosol (SA) formation can be affected by relative humidity (RH) and has different influences on the particle CCN activity under different RH conditions. In the North China Plain, we find different responses of CCN activity and enhancements of CCN number concentration to SA formation under different RH conditions. In addition, variations of aerosol mixing state due to SA formation contribute some of the largest uncertainties in predicting CCN number concentration.
Caroline C. Womack, Katherine M. Manfred, Nicholas L. Wagner, Gabriela Adler, Alessandro Franchin, Kara D. Lamb, Ann M. Middlebrook, Joshua P. Schwarz, Charles A. Brock, Steven S. Brown, and Rebecca A. Washenfelder
Atmos. Chem. Phys., 21, 7235–7252, https://doi.org/10.5194/acp-21-7235-2021, https://doi.org/10.5194/acp-21-7235-2021, 2021
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Microscopic particles interact with sunlight and affect the earth's climate in ways that are not fully understood. Aerosols from wildfire smoke present particular challenges due to their complexity in shape and composition. We demonstrate that we can experimentally measure aerosol optical properties for many types of smoke particles, using measurements of smoke from controlled burns, but that the method does not work well for smoke with high soot content.
Anna L. Hodshire, Emily Ramnarine, Ali Akherati, Matthew L. Alvarado, Delphine K. Farmer, Shantanu H. Jathar, Sonia M. Kreidenweis, Chantelle R. Lonsdale, Timothy B. Onasch, Stephen R. Springston, Jian Wang, Yang Wang, Lawrence I. Kleinman, Arthur J. Sedlacek III, and Jeffrey R. Pierce
Atmos. Chem. Phys., 21, 6839–6855, https://doi.org/10.5194/acp-21-6839-2021, https://doi.org/10.5194/acp-21-6839-2021, 2021
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Biomass burning emits particles and vapors that can impact both health and climate. Here, we investigate the role of dilution in the evolution of aerosol size and composition in observed US wildfire smoke plumes. Centers of plumes dilute more slowly than edges. We see differences in concentrations and composition between the centers and edges both in the first measurement and in subsequent measurements. Our findings support the hypothesis that plume dilution influences smoke aging.
Maria Kezoudi, Matthias Tesche, Helen Smith, Alexandra Tsekeri, Holger Baars, Maximilian Dollner, Víctor Estellés, Johannes Bühl, Bernadett Weinzierl, Zbigniew Ulanowski, Detlef Müller, and Vassilis Amiridis
Atmos. Chem. Phys., 21, 6781–6797, https://doi.org/10.5194/acp-21-6781-2021, https://doi.org/10.5194/acp-21-6781-2021, 2021
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Mineral dust concentrations in the diameter range from 0.4 to 14.0 μm were measured with the balloon-borne UCASS optical particle counter. Launches were coordinated with ground-based remote-sensing and airborne in situ measurements during a Saharan dust outbreak over Cyprus. Particle number concentrations reached 50 cm−3 for the diameter range 0.8–13.9 μm. Comparisons with aircraft data show reasonable agreement in magnitude and shape of the particle size distribution.
Anbao Zhu, Haiming Xu, Jiechun Deng, Jing Ma, and Shuhui Li
Atmos. Chem. Phys., 21, 5919–5933, https://doi.org/10.5194/acp-21-5919-2021, https://doi.org/10.5194/acp-21-5919-2021, 2021
Dandan Zhao, Jinyuan Xin, Chongshui Gong, Jiannong Quan, Yuesi Wang, Guiqian Tang, Yongxiang Ma, Lindong Dai, Xiaoyan Wu, Guangjing Liu, and Yongjing Ma
Atmos. Chem. Phys., 21, 5739–5753, https://doi.org/10.5194/acp-21-5739-2021, https://doi.org/10.5194/acp-21-5739-2021, 2021
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The influence of aerosol radiative forcing (ARF) on the boundary layer structure is nonlinear. The threshold of the modification effects of ARF on the boundary layer structure was determined for the first time, highlighting that once ARF exceeded a certain value, the boundary layer would quickly stabilize and aggravate air pollution. This could provide useful information for relevant atmospheric-environment improvement measures and policies.
Long Peng, Lei Li, Guohua Zhang, Xubing Du, Xinming Wang, Ping'an Peng, Guoying Sheng, and Xinhui Bi
Atmos. Chem. Phys., 21, 5605–5613, https://doi.org/10.5194/acp-21-5605-2021, https://doi.org/10.5194/acp-21-5605-2021, 2021
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We build a novel system that utilizes an aerodynamic aerosol classifier (AAC) combined with a single-particle aerosol mass spectrometry (SPAMS) to simultaneously characterize the volume equivalent diameter (Dve), chemical compositions, and effective density (ρe) of individual particles in real time. A test of the AAC-SPAMS with both spherical and aspherical particles shows that the deviations between the measured and theoretical values are less than 6 %.
Luca Ferrero, Asta Gregorič, Griša Močnik, Martin Rigler, Sergio Cogliati, Francesca Barnaba, Luca Di Liberto, Gian Paolo Gobbi, Niccolò Losi, and Ezio Bolzacchini
Atmos. Chem. Phys., 21, 4869–4897, https://doi.org/10.5194/acp-21-4869-2021, https://doi.org/10.5194/acp-21-4869-2021, 2021
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The work experimentally quantifies the impact of cloudiness and cloud type on the atmospheric heating rate of black and brown carbon. The most impacting clouds were stratocumulus, altostratus and stratus. Clouds caused a decrease of the heating rate of about 12 % per okta. The black carbon decease was slightly higher with respect to that of brown carbon. This study highlights the need to take into account the role of cloudiness when modelling light-absorbing aerosol climate forcing.
Roland Stirnberg, Jan Cermak, Simone Kotthaus, Martial Haeffelin, Hendrik Andersen, Julia Fuchs, Miae Kim, Jean-Eudes Petit, and Olivier Favez
Atmos. Chem. Phys., 21, 3919–3948, https://doi.org/10.5194/acp-21-3919-2021, https://doi.org/10.5194/acp-21-3919-2021, 2021
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Air pollution endangers human health and poses a problem particularly in densely populated areas. Here, an explainable machine learning approach is used to analyse periods of high particle concentrations for a suburban site southwest of Paris to better understand its atmospheric drivers. Air pollution is particularly excaberated by low temperatures and low mixed layer heights, but processes vary substantially between and within seasons.
Julia Schneider, Kristina Höhler, Paavo Heikkilä, Jorma Keskinen, Barbara Bertozzi, Pia Bogert, Tobias Schorr, Nsikanabasi Silas Umo, Franziska Vogel, Zoé Brasseur, Yusheng Wu, Simo Hakala, Jonathan Duplissy, Dmitri Moisseev, Markku Kulmala, Michael P. Adams, Benjamin J. Murray, Kimmo Korhonen, Liqing Hao, Erik S. Thomson, Dimitri Castarède, Thomas Leisner, Tuukka Petäjä, and Ottmar Möhler
Atmos. Chem. Phys., 21, 3899–3918, https://doi.org/10.5194/acp-21-3899-2021, https://doi.org/10.5194/acp-21-3899-2021, 2021
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By triggering the formation of ice crystals, ice-nucleating particles (INP) strongly influence cloud formation. Continuous, long-term measurements are needed to characterize the atmospheric INP variability. Here, a first long-term time series of INP spectra measured in the boreal forest for more than 1 year is presented, showing a clear seasonal cycle. It is shown that the seasonal dependency of INP concentrations and prevalent INP types is driven by the abundance of biogenic aerosol.
Marco Zanatta, Andreas Herber, Zsófia Jurányi, Oliver Eppers, Johannes Schneider, and Joshua P. Schwarz
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-182, https://doi.org/10.5194/acp-2021-182, 2021
Revised manuscript accepted for ACP
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Saline snow samples were collected of the sea ice in the Fram Strait. Laboratory experiments revealed that sea salt can bias the quantification of black carbon with laser induced incandescence technique. The maximum underestimation was quantified to reach values of 80–90 %. This salt induced interference is reported here for the first time and should be considered in future studies aiming to quantify black carbon in snow in marine environments.
Kevin J. Sanchez, Gregory C. Roberts, Georges Saliba, Lynn M. Russell, Cynthia Twohy, J. Michael Reeves, Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, and Ian M. McRobert
Atmos. Chem. Phys., 21, 3427–3446, https://doi.org/10.5194/acp-21-3427-2021, https://doi.org/10.5194/acp-21-3427-2021, 2021
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Measurements of particles and their properties were made from aircraft over the Southern Ocean. Aerosol transported from the Antarctic coast is shown to greatly enhance particle concentrations over the Southern Ocean. The occurrence of precipitation was shown to be associated with the lowest particle concentrations over the Southern Ocean. These particles are important due to their ability to enhance cloud droplet concentrations, resulting in more sunlight being reflected by the clouds.
Sami D. Seppälä, Joel Kuula, Antti-Pekka Hyvärinen, Sanna Saarikoski, Topi Rönkkö, Jorma Keskinen, Jukka-Pekka Jalkanen, and Hilkka Timonen
Atmos. Chem. Phys., 21, 3215–3234, https://doi.org/10.5194/acp-21-3215-2021, https://doi.org/10.5194/acp-21-3215-2021, 2021
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The effects of fuel sulfur content restrictions implemented by the International Maritime Organization in the Baltic Sea (in July 2010 and January 2015) on the particle properties of ship exhaust plumes and ambient aerosol were studied. The restrictions reduced the particle number concentrations and median particle size in plumes and number concentrations in ambient aerosol. These changes may improve human health in coastal areas and decrease the cooling effect of exhaust emissions from ships.
Christian Zdanowicz, Jean-Charles Gallet, Mats P. Björkman, Catherine Larose, Thomas Schuler, Bartłomiej Luks, Krystyna Koziol, Andrea Spolaor, Elena Barbaro, Tõnu Martma, Ward van Pelt, Ulla Wideqvist, and Johan Ström
Atmos. Chem. Phys., 21, 3035–3057, https://doi.org/10.5194/acp-21-3035-2021, https://doi.org/10.5194/acp-21-3035-2021, 2021
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Black carbon (BC) aerosols are soot-like particles which, when transported to the Arctic, darken snow surfaces, thus indirectly affecting climate. Information on BC in Arctic snow is needed to measure their impact and monitor the efficacy of pollution-reduction policies. This paper presents a large new set of BC measurements in snow in Svalbard collected between 2007 and 2018. It describes how BC in snow varies across the archipelago and explores some factors controlling these variations.
Jonas Svensson, Johan Ström, Henri Honkanen, Eija Asmi, Nathaniel B. Dkhar, Shresth Tayal, Ved P. Sharma, Rakesh Hooda, Matti Leppäranta, Hans-Werner Jacobi, Heikki Lihavainen, and Antti Hyvärinen
Atmos. Chem. Phys., 21, 2931–2943, https://doi.org/10.5194/acp-21-2931-2021, https://doi.org/10.5194/acp-21-2931-2021, 2021
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Light-absorbing particles specifically affect snowmelt in the Himalayas. Through measurements of the constituents in glacier snow pits from the Indian Himalayas our investigations show that different snow layers display striking similarities. These similarities can be characterized by a deposition constant. Our results further indicate that mineral dust can be responsible for the majority of light absorption in the snow in this part of the Himalayas.
Imre Salma, Wanda Thén, Pasi Aalto, Veli-Matti Kerminen, Anikó Kern, Zoltán Barcza, Tuukka Petäjä, and Markku Kulmala
Atmos. Chem. Phys., 21, 2861–2880, https://doi.org/10.5194/acp-21-2861-2021, https://doi.org/10.5194/acp-21-2861-2021, 2021
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The distribution of the monthly mean nucleation frequency possessed a characteristic pattern. Its shape was compared to those of environmental variables, including vegetation-derived properties. The spring maximum in the occurrence frequency often overlapped with the positive T anomaly. The link between the heat stress and the occurrence minimum in summer could not be proven, whereas an association between the occurrence frequency and vegetation growth dynamics was clearly identified in spring.
Xiaoyan Wang, Renhe Zhang, Yanke Tan, and Wei Yu
Atmos. Chem. Phys., 21, 2491–2508, https://doi.org/10.5194/acp-21-2491-2021, https://doi.org/10.5194/acp-21-2491-2021, 2021
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The physical mechanisms of synoptic patterns affecting the decay process of air pollution episodes are investigated in this work. Three dominant circulation patterns are identified, which usually decrease the ambient PM2.5 concentrations by 27%–41% after they arrive around Beijing. Emission reductions led to a 4.3–5.7 μg (m3 yr-1)-1 decrease in PM2.5 concentrations around Beijing during 2014 to 2020.
Simone Brunamonti, Giovanni Martucci, Gonzague Romanens, Yann Poltera, Frank G. Wienhold, Maxime Hervo, Alexander Haefele, and Francisco Navas-Guzmán
Atmos. Chem. Phys., 21, 2267–2285, https://doi.org/10.5194/acp-21-2267-2021, https://doi.org/10.5194/acp-21-2267-2021, 2021
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Lidar (light detection and ranging) is a class of remote-sensing instruments that are widely used for the monitoring of aerosol properties in the lower levels of the atmosphere, yet their measurements are affected by several sources of uncertainty. Here we present the first comparison of two lidar systems against a fully independent instrument carried by meteorological balloons. We show that both lidars achieve a good agreement with the high-precision balloon measurements up to 6 km altitude.
Runlong Cai, Chenxi Li, Xu-Cheng He, Chenjuan Deng, Yiqun Lu, Rujing Yin, Chao Yan, Lin Wang, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 21, 2287–2304, https://doi.org/10.5194/acp-21-2287-2021, https://doi.org/10.5194/acp-21-2287-2021, 2021
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Growth rate determines the survival probability of atmospheric new particles and hence their impacts. We clarify the impacts of coagulation on the values retrieved by the appearance time method, which is widely used for growth rate evaluation. A new formula with coagulation correction is proposed based on derivation and tested using both models and atmospheric data. We show that the sub-3 nm particle growth rate in polluted environments may be overestimated without the coagulation correction.
Jean-François Léon, Aristide Barthélémy Akpo, Mouhamadou Bedou, Julien Djossou, Marleine Bodjrenou, Véronique Yoboué, and Cathy Liousse
Atmos. Chem. Phys., 21, 1815–1834, https://doi.org/10.5194/acp-21-1815-2021, https://doi.org/10.5194/acp-21-1815-2021, 2021
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We have investigated the aerosol optical depth (AOD) and its relation to PM2.5 surface concentrations in southern West Africa based on in situ observations (2015–2017 period) and MODIS satellite data (2003–2019). MODIS AODs are validated using a regional network of handheld and automatic sun photometers. Satellite-derived PM2.5 shows an increasing trend during the short dry period that is possibly linked to the increase in anthropogenic emission over this area.
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.
Jessie M. Creamean, Gijs de Boer, Hagen Telg, Fan Mei, Darielle Dexheimer, Matthew D. Shupe, Amy Solomon, and Allison McComiskey
Atmos. Chem. Phys., 21, 1737–1757, https://doi.org/10.5194/acp-21-1737-2021, https://doi.org/10.5194/acp-21-1737-2021, 2021
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Arctic clouds play a role in modulating sea ice extent. Importantly, aerosols facilitate cloud formation, and thus it is crucial to understand the interactions between aerosols and clouds. Vertical measurements of aerosols and clouds are needed to tackle this issue. We present results from balloon-borne measurements of aerosols and clouds over the course of 2 years in northern Alaska. These data shed light onto the vertical distributions of aerosols relative to clouds spanning multiple seasons.
Wei Xu, Kirsten N. Fossum, Jurgita Ovadnevaite, Chunshui Lin, Ru-Jin Huang, Colin O'Dowd, and Darius Ceburnis
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-96, https://doi.org/10.5194/acp-2021-96, 2021
Revised manuscript accepted for ACP
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Could condensation nuclei (CCN) is an important topic in atmospheric studies, especially for evaluating the climate impact of aerosol. Here in this study, CCN closure study by using chemical composition based on aerosol mass spectrometer (AMS) and hygroscopicity growth measurements based on humidified tandem differential mobility analyzer (HTDMA) in the Mace Head Atmospheric Research Station.
Jens Redemann, Robert Wood, Paquita Zuidema, Sarah J. Doherty, Bernadette Luna, Samuel E. LeBlanc, Michael S. Diamond, Yohei Shinozuka, Ian Y. Chang, Rei Ueyama, Leonhard Pfister, Ju-Mee Ryoo, Amie N. Dobracki, Arlindo M. da Silva, Karla M. Longo, Meloë S. Kacenelenbogen, Connor J. Flynn, Kristina Pistone, Nichola M. Knox, Stuart J. Piketh, James M. Haywood, Paola Formenti, Marc Mallet, Philip Stier, Andrew S. Ackerman, Susanne E. Bauer, Ann M. Fridlind, Gregory R. Carmichael, Pablo E. Saide, Gonzalo A. Ferrada, Steven G. Howell, Steffen Freitag, Brian Cairns, Brent N. Holben, Kirk D. Knobelspiesse, Simone Tanelli, Tristan S. L'Ecuyer, Andrew M. Dzambo, Ousmane O. Sy, Greg M. McFarquhar, Michael R. Poellot, Siddhant Gupta, Joseph R. O'Brien, Athanasios Nenes, Mary Kacarab, Jenny P. S. Wong, Jennifer D. Small-Griswold, Kenneth L. Thornhill, David Noone, James R. Podolske, K. Sebastian Schmidt, Peter Pilewskie, Hong Chen, Sabrina P. Cochrane, Arthur J. Sedlacek, Timothy J. Lang, Eric Stith, Michal Segal-Rozenhaimer, Richard A. Ferrare, Sharon P. Burton, Chris A. Hostetler, David J. Diner, Felix C. Seidel, Steven E. Platnick, Jeffrey S. Myers, Kerry G. Meyer, Douglas A. Spangenberg, Hal Maring, and Lan Gao
Atmos. Chem. Phys., 21, 1507–1563, https://doi.org/10.5194/acp-21-1507-2021, https://doi.org/10.5194/acp-21-1507-2021, 2021
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Southern Africa produces significant biomass burning emissions whose impacts on regional and global climate are poorly understood. ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) is a 5-year NASA investigation designed to study the key processes that determine these climate impacts. The main purpose of this paper is to familiarize the broader scientific community with the ORACLES project, the dataset it produced, and the most important initial findings.
Chuanyang Shen, Gang Zhao, Weilun Zhao, Ping Tian, and Chunsheng Zhao
Atmos. Chem. Phys., 21, 1375–1388, https://doi.org/10.5194/acp-21-1375-2021, https://doi.org/10.5194/acp-21-1375-2021, 2021
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Submicron particles larger than 300 nm dominate the aerosol light extinction and mass concentration in the urban environment. Aerosol hygroscopic properties extended to 600 nm were investigated at an urban site. Our results find that there exists a large fraction of a less hygroscopic group above 300 nm, and the hygroscopicity in this size range is enhanced significantly with the development of pollution levels. The hygroscopicity variation contributes greatly to the low visibility.
Huihui Wu, Jonathan W. Taylor, Justin M. Langridge, Chenjie Yu, James D. Allan, Kate Szpek, Michael I. Cotterell, Paul I. Williams, Michael Flynn, Patrick Barker, Cathryn Fox, Grant Allen, James Lee, and Hugh Coe
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-49, https://doi.org/10.5194/acp-2021-49, 2021
Revised manuscript accepted for ACP
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Seasonal biomass burning over West Africa is a globally significant source of carbonaceous particles in the atmosphere, which have important climate impacts but are poorly constrained. We conducted in-situ airborne measurements to investigate the evolution of smoke aerosol properties in this region. We observed absorption enhancement for both the black carbon and brown carbon after emission, which provide new field results and constraints on aerosol parameterisations for future climate models.
Krista Luoma, Jarkko V. Niemi, Minna Aurela, Pak Lun Fung, Aku Helin, Tareq Hussein, Leena Kangas, Anu Kousa, Topi Rönkkö, Hilkka Timonen, Aki Virkkula, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 1173–1189, https://doi.org/10.5194/acp-21-1173-2021, https://doi.org/10.5194/acp-21-1173-2021, 2021
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This study combined black carbon measurements from 15 Finnish sites that represented different environments (traffic, detached housing area, urban background, and regional background). The seasonal and diurnal variations in the black carbon concentration were associated with local emissions from traffic and residential wood burning. The study observed decreasing trends in the black carbon concentration and associated them with decreases in traffic emissions.
Nobuyuki Takegawa, Yoshiko Murashima, Akihiro Fushimi, Kentaro Misawa, Yuji Fujitani, Katsumi Saitoh, and Hiromu Sakurai
Atmos. Chem. Phys., 21, 1085–1104, https://doi.org/10.5194/acp-21-1085-2021, https://doi.org/10.5194/acp-21-1085-2021, 2021
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The characterization of particle emissions from aircraft is important for the assessment of the aviation impacts on climate and human health. We conducted field observations of aerosols near a runway at Narita International Airport in February 2018. We investigated particle number emissions from in-use commercial aircraft under real-world operating conditions, and we found the significance of sub-10 nm size ranges in take-off plumes for both total and non-volatile particles.
Jim M. Haywood, Steven J. Abel, Paul A. Barrett, Nicolas Bellouin, Alan Blyth, Keith N. Bower, Melissa Brooks, Ken Carslaw, Haochi Che, Hugh Coe, Michael I. Cotterell, Ian Crawford, Zhiqiang Cui, Nicholas Davies, Beth Dingley, Paul Field, Paola Formenti, Hamish Gordon, Martin de Graaf, Ross Herbert, Ben Johnson, Anthony C. Jones, Justin M. Langridge, Florent Malavelle, Daniel G. Partridge, Fanny Peers, Jens Redemann, Philip Stier, Kate Szpek, Jonathan W. Taylor, Duncan Watson-Parris, Robert Wood, Huihui Wu, and Paquita Zuidema
Atmos. Chem. Phys., 21, 1049–1084, https://doi.org/10.5194/acp-21-1049-2021, https://doi.org/10.5194/acp-21-1049-2021, 2021
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Every year, the seasonal cycle of biomass burning from agricultural practices in Africa creates a huge plume of smoke that travels many thousands of kilometres over the Atlantic Ocean. This study provides an overview of a measurement campaign called the cloud–aerosol–radiation interaction and forcing for year 2017 (CLARIFY-2017) and documents the rationale, deployment strategy, observations, and key results from the campaign which utilized the heavily equipped FAAM atmospheric research aircraft.
Huikun Liu, Qiyuan Wang, Li Xing, Yong Zhang, Ting Zhang, Weikang Ran, and Junji Cao
Atmos. Chem. Phys., 21, 973–987, https://doi.org/10.5194/acp-21-973-2021, https://doi.org/10.5194/acp-21-973-2021, 2021
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We conducted black carbon (BC) source apportionment on the southeastern Tibetan Plateau (TP) by an improved aethalometer model with the site-dependent Ångström exponent and BC mass absorption cross section (MAC). The result shows that the biomass-burning BC on the TP is slightly higher than fossil fuel BC, mainly from cross-border transportation instead of the local region, and the BC radiative effect is lower than that in the southwestern Himalaya but higher than that on the northeastern TP.
Vasiliki Daskalopoulou, Sotirios A. Mallios, Zbigniew Ulanowski, George Hloupis, Anna Gialitaki, Ioanna Tsikoudi, Konstantinos Tassis, and Vassilis Amiridis
Atmos. Chem. Phys., 21, 927–949, https://doi.org/10.5194/acp-21-927-2021, https://doi.org/10.5194/acp-21-927-2021, 2021
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This research highlights the detection of charged Saharan dust in Greece and provides indications of charge separation in the plumes through the first-ever co-located ground electric field measurements and sophisticated lidar observations. We provide a robust methodology for the extraction of a fair-weather proxy field used to assess the effect of lofted dust particles to the electric field and insert a realistic modelling aspect to the charge accumulation areas within electrically active dust.
Juha Sulo, Nina Sarnela, Jenni Kontkanen, Lauri Ahonen, Pauli Paasonen, Tiia Laurila, Tuija Jokinen, Juha Kangasluoma, Heikki Junninen, Mikko Sipilä, Tuukka Petäjä, Markku Kulmala, and Katrianne Lehtipalo
Atmos. Chem. Phys., 21, 695–715, https://doi.org/10.5194/acp-21-695-2021, https://doi.org/10.5194/acp-21-695-2021, 2021
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In this study, we analyzed over 5 years of sub-3 nm particle concentrations and their precursor vapors, identifying atmoshperic vapors important to the formation of these particles in the boreal forest. We also observed seasonal differences in both particle and precursor vapor concentrations and the formation pathways of these particles. Our results confirm the importance of organic vapors in atmospheric aerosol formation and highlight key seasonal differences that require further study.
Jinfeng Yuan, Robin Lewis Modini, Marco Zanatta, Andreas B. Herber, Thomas Müller, Birgit Wehner, Laurent Poulain, Thomas Tuch, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Chem. Phys., 21, 635–655, https://doi.org/10.5194/acp-21-635-2021, https://doi.org/10.5194/acp-21-635-2021, 2021
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Black carbon (BC) aerosols contribute substantially to climate warming due to their unique light absorption capabilities. We performed field measurements at a central European background site in winter and found that variability in the absorption efficiency of BC particles is driven mainly by their internal mixing state. Our results suggest that, at this site, knowing the BC mixing state is sufficient to describe BC light absorption enhancements due to the lensing effect in good approximation.
Shuo Ding, Dantong Liu, Kang Hu, Delong Zhao, Ping Tian, Fei Wang, Ruijie Li, Yichen Chen, Hui He, Mengyu Huang, and Deping Ding
Atmos. Chem. Phys., 21, 681–694, https://doi.org/10.5194/acp-21-681-2021, https://doi.org/10.5194/acp-21-681-2021, 2021
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In this study, we for the first time characterized the detailed black carbon (BC) microphysics at a mountain site located at the top of the planetary boundary layer (PBL) influenced by surface emission over the North China Plain. We investigated the optical and hygroscopic properties of BC at this level as influenced by microphysical properties. Such information will constrain the impacts of BC in influencing the PBL dynamics and low-level cloud formation over anthropogenically polluted regions.
Rongmin Ren, Zhanqing Li, Peng Yan, Yuying Wang, Hao Wu, Wei Wang, Xiao'ai Jin, Yanan Li, Dongmei Zhang, and Maureen Cribb
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1238, https://doi.org/10.5194/acp-2020-1238, 2021
Revised manuscript accepted for ACP
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We analyzed the effect of the proportion of components making up the chemical composition of aerosols on f(RH) in southern Beijing in 2019. Nitrate played a more significant role in affecting f(RH) than sulfate. The ratio of the sulfate mass fraction to the nitrate mass fraction (mostly higher than ~4) was a sign of the deliquescence of aerosol. A piecewise parameterized scheme was proposed, which could better describe deliquescence and reduce uncertainties in simulating aerosol hygroscopicity.
David Brus, Jani Gustafsson, Ville Vakkari, Osku Kemppinen, Gijs de Boer, and Anne Hirsikko
Atmos. Chem. Phys., 21, 517–533, https://doi.org/10.5194/acp-21-517-2021, https://doi.org/10.5194/acp-21-517-2021, 2021
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This paper summarizes Finnish Meteorological Institute and Kansas State University unmanned aerial vehicle measurements during the summer 2018 Lower Atmospheric Process Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (LAPSE-RATE) campaign in the San Luis Valley, providing an overview of the rotorcraft deployed, payloads, scientific goals and flight strategies and presenting observations of atmospheric thermodynamics and aerosol and gas parameters in the vertical column.
Jesús Yus-Díez, Marina Ealo, Marco Pandolfi, Noemí Perez, Gloria Titos, Griša Močnik, Xavier Querol, and Andrés Alastuey
Atmos. Chem. Phys., 21, 431–455, https://doi.org/10.5194/acp-21-431-2021, https://doi.org/10.5194/acp-21-431-2021, 2021
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Here we describe the vertical profiles of extensive (scattering and absorption) and intensive (e.g. albedo and asymmetry parameter) aerosol optical properties from coupling ground-based measurements from two sites in north-eastern Spain and airborne measurements performed with an aircraft. We analyse different aerosol layers along the vertical profile for a regional pollution episode and a Saharan dust intrusion. The results show a change with height depending on the different measured layers.
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
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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.
Rutambhara Joshi, Dantong Liu, Eiko Nemitz, Ben Langford, Neil Mullinger, Freya Squires, James Lee, Yunfei Wu, Xiaole Pan, Pingqing Fu, Simone Kotthaus, Sue Grimmond, Qiang Zhang, Ruili Wu, Oliver Wild, Michael Flynn, Hugh Coe, and James Allan
Atmos. Chem. Phys., 21, 147–162, https://doi.org/10.5194/acp-21-147-2021, https://doi.org/10.5194/acp-21-147-2021, 2021
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Black carbon (BC) is a component of particulate matter which has significant effects on climate and human health. Sources of BC include biomass burning, transport, industry and domestic cooking and heating. In this study, we measured BC emissions in Beijing, finding a dominance of traffic emissions over all other sources. The quantitative method presented here has benefits for revising widely used emissions inventories and for understanding BC sources with impacts on air quality and climate.
Mohanan R. Manoj, Sreedharan K. Satheesh, Krishnaswamy K. Moorthy, Jamie Trembath, and Hugh Coe
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1233, https://doi.org/10.5194/acp-2020-1233, 2020
Revised manuscript accepted for ACP
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Vertical distributions of atmospheric aerosols and the ability of aerosols to form clouds has been studied across the Indo-Gangetic Plain based on air-borne measurements carried out during the SWAAMI field campaign studying the Indian monsoon. The ability of the aerosols to act as cloud forming nuclei showed contrasting features, increasing with increase in altitude, prior to the onset of monsoon, reversing the trend to decrease with increase in altitude during the active phase of the monsoon.
Joseph Ko, Trevor Krasowsky, and George Ban-Weiss
Atmos. Chem. Phys., 20, 15635–15664, https://doi.org/10.5194/acp-20-15635-2020, https://doi.org/10.5194/acp-20-15635-2020, 2020
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Black carbon (BC) is the second strongest climate forcing pollutant in the atmosphere, after carbon dioxide. Here, we seek to understand how BC microphysical properties vary with atmospheric contexts, as these properties can influence its radiative forcing. Consistent with previous studies, we found that biomass burning BC had thicker coatings and larger core diameters than fossil fuel BC. We also present evidence to show that atmospheric aging also increases BC coating thickness.
Imre Salma, Máté Vörösmarty, András Zénó Gyöngyösi, Wanda Thén, and Tamás Weidinger
Atmos. Chem. Phys., 20, 15725–15742, https://doi.org/10.5194/acp-20-15725-2020, https://doi.org/10.5194/acp-20-15725-2020, 2020
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Motor vehicle road traffic in Budapest was reduced by approximately 50% of its ordinary level due to COVID-19. In parallel, concentrations of most criteria air pollutants declined by 30–60%. Change rates of NO and NO2 with relative change in traffic intensity were the largest, total particle number concentration showed considerable dependency, while particulate matter mass concentrations did not appear to be related to urban traffic. Concentrations of O3 showed an increasing tendency.
Mingfu Cai, Baoling Liang, Qibin Sun, Li Liu, Bin Yuan, Min Shao, Shan Huang, Yuwen Peng, Zelong Wang, Haobo Tan, Fei Li, Hanbin Xu, and Jun Zhao
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1203, https://doi.org/10.5194/acp-2020-1203, 2020
Revised manuscript accepted for ACP
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This study investigated the contribution of new particle formation (NPF) events to the number concentration of cloud condensation nuclei (NCCN) and its controlling factors in the Pearl River Delta region. The results show that the surfactant effect can decrease the critical diameter and significantly increase the NCCN during the NPF event. In addition, the growth rate is founded to be the most important controlling factor that affects NCCN for growth of newly-formed particles to the CCN sizes.
Qiyuan Wang, Li Li, Jiamao Zhou, Jianhuai Ye, Wenting Dai, Huikun Liu, Yong Zhang, Renjian Zhang, Jie Tian, Yang Chen, Yunfei Wu, Weikang Ran, and Junji Cao
Atmos. Chem. Phys., 20, 15427–15442, https://doi.org/10.5194/acp-20-15427-2020, https://doi.org/10.5194/acp-20-15427-2020, 2020
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Recently, China has promulgated a series of regulations to reduce air pollutants. The decreased black carbon (BC) and co-emitted pollutants could affect the interactions between BC and other aerosols, which in turn results in changes in BC. Herein, we re-assessed the characteristics of BC of a representative pollution site in northern China in the final year of the Chinese
Action Plan for the Prevention and Control of Air Pollution.
Agnieszka Kupc, Christina J. Williamson, Anna L. Hodshire, Jan Kazil, Eric Ray, T. Paul Bui, Maximilian Dollner, Karl D. Froyd, Kathryn McKain, Andrew Rollins, Gregory P. Schill, Alexander Thames, Bernadett B. Weinzierl, Jeffrey R. Pierce, and Charles A. Brock
Atmos. Chem. Phys., 20, 15037–15060, https://doi.org/10.5194/acp-20-15037-2020, https://doi.org/10.5194/acp-20-15037-2020, 2020
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Tropical upper troposphere over the Atlantic and Pacific oceans is a major source region of new particles. These particles are associated with the outflow from deep convection. We investigate the processes that govern the formation of these particles and their initial growth and show that none of the formation schemes commonly used in global models are consistent with observations. Using newer schemes indicates that organic compounds are likely important as nucleating and initial growth agents.
Yuan Wang, Xiaojian Zheng, Xiquan Dong, Baike Xi, Peng Wu, Timothy Logan, and Yuk L. Yung
Atmos. Chem. Phys., 20, 14741–14755, https://doi.org/10.5194/acp-20-14741-2020, https://doi.org/10.5194/acp-20-14741-2020, 2020
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A recent aircraft field campaign near the Azores in the summer of 2017 provides ample observations of aerosols and clouds with detailed vertical information. This study utilizes those observational data in combination with the aerosol-aware large-eddy simulations and aerosol reanalysis data to examine the significance of the long-range-transported aerosol effect on marine-boundary-layer clouds. It is the first time that the ACE-ENA aircraft campaign data are used for this topic.
Tianyi Tan, Min Hu, Zhuofei Du, Gang Zhao, Dongjie Shang, Jing Zheng, Yanhong Qin, Mengren Li, Yusheng Wu, Limin Zeng, Song Guo, and Zhijun Wu
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1150, https://doi.org/10.5194/acp-2020-1150, 2020
Revised manuscript accepted for ACP
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Every year in the pre-monsoon season, the black carbon (BC) aerosols originated from the biomass burning in southern Asia are easily transported to the Tibetan Plateau (TP) by the convenience of westerly wind. This study reveals that the BC aerosols in the aged biomass burning plumes strongly enhance the total light absorption over the TP, and the aging process during the long-range transport will further strengthen the radiative heating of those BC aerosols.
Paraskevi Georgakaki, Aikaterini Bougiatioti, Jörg Wieder, Claudia Mignani, Fabiola Ramelli, Zamin A. Kanji, Jan Henneberger, Maxime Hervo, Alexis Berne, Ulrike Lohmann, and Athanasios Nenes
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1036, https://doi.org/10.5194/acp-2020-1036, 2020
Revised manuscript accepted for ACP
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Aerosol and cloud observations coupled with a droplet activation parameterization was used to investigate the aerosol-cloud droplet link in mixed-phase Alpine clouds. Predicted droplet number, Nd, agrees with observations, and never exceeds a characteristic
limiting droplet number, Ndlim, which depends solely on σw. Nd becomes velocity-limited when it is to within 50 % of Ndlim. Identifying when dynamical changes control Nd variability is central for understanding aerosol-cloud interactions.
Douglas Morrison, Ian Crawford, Nicholas Marsden, Michael Flynn, Katie Read, Luis Neves, Virginia Foot, Paul Kaye, Warren Stanley, Hugh Coe, David Topping, and Martin Gallagher
Atmos. Chem. Phys., 20, 14473–14490, https://doi.org/10.5194/acp-20-14473-2020, https://doi.org/10.5194/acp-20-14473-2020, 2020
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We provide conservative estimates of the concentrations of bacteria within transatlantic dust clouds, originating from the African continent. We observe significant seasonal differences in the overall concentrations of particles but no seasonal variation in the ratio between bacteria and dust. With bacteria contributing to ice formation at warmer temperatures than dust, our observations should improve the accuracy of climate models.
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