Articles | Volume 9, issue 19
© Author(s) 2009. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
© Author(s) 2009. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Chemical apportionment of southern African aerosol mass and optical depth
B. I. Magi
Atmospheric and Oceanic Sciences, Princeton University, Princeton, New Jersey, USA
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)Characterization of ultrafine particles and the occurrence of new particle formation events in an urban and coastal site of the Mediterranean areaAtmospheric nanoparticles hygroscopic growth measurement by a combined surface plasmon resonance microscope and hygroscopic tandem differential mobility analyzerA full year of aerosol size distribution data from the central Arctic under an extreme positive Arctic Oscillation: insights from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expeditionAnnual cycle of hygroscopic properties and mixing state of the suburban aerosol in Athens, GreeceMeasurement report: Atmospheric new particle formation at a peri-urban site in Lille, northern FranceNew particle formation and growth during summer in an urban environment: a dual chamber studyAn evaluation of biomass burning aerosol mass, extinction, and size distribution in GEOS using observations from CAMP2ExSeasonal significance of new particle formation impacts on cloud condensation nuclei at a mountaintop locationAerosol activation characteristics and prediction at the central European ACTRIS research station of Melpitz, GermanyMeasurement report: Increasing trend of atmospheric ion concentrations in the boreal forestQuantifying particle-to-particle heterogeneity in aerosol hygroscopicityVertical profiles of cloud condensation nuclei number concentration and its empirical estimate from aerosol optical properties over the North China PlainMeasurement report: The Urmia playa as a source of airborne dust and ice-nucleating particles – Part 1: Correlation between soils and airborne samplesConstraining the particle-scale diversity of black carbon light absorption using a unified frameworkSurvival probability of new atmospheric particles: closure between theory and measurements from 1.4 to 100 nmPredicting atmospheric background number concentration of ice-nucleating particles in the ArcticDifferent effects of anthropogenic emissions and aging processes on the mixing state of soot particles in the nucleation and accumulation modesFluorescence characteristics, absorption properties, and radiative effects of water-soluble organic carbon in seasonal snow across northeastern ChinaMeasurement report: Size distributions of urban aerosols down to 1 nm from long-term measurementsRapid reappearance of air pollution after cold air outbreaks in northern and eastern ChinaOn the relation between apparent ion and total particle growth rates in the boreal forest and related chamber experimentsAssessment of NAAPS-RA performance in Maritime Southeast Asia during CAMP2ExComparison of particle number size distribution trends in ground measurements and climate modelsAerosol size distribution changes in FIREX-AQ biomass burning plumes: the impact of plume concentration on coagulation and OA condensation/evaporationLong-range transported continental aerosol in the Eastern North Atlantic: three multiday event regimes influence cloud condensation nucleiImpact of water uptake and mixing state on submicron particle deposition in the human respiratory tract (HRT) based on explicit hygroscopicity measurements at HRT-like conditionsParameterizations of size distribution and refractive index of biomass burning organic aerosol with black carbon contentNewly identified climatically and environmentally significant high-latitude dust sourcesMeasurement Report: Understanding the seasonal cycle of Southern Ocean aerosolsDifferent aerosol effects on the daytime and nocturnal cloud-to-ground lightning in the Sichuan BasinAirborne observations during KORUS-AQ show that aerosol optical depths are more spatially self-consistent than aerosol intensive propertiesUsing aircraft measurements to characterize subgrid-scale variability of aerosol properties near the Atmospheric Radiation Measurement Southern Great Plains siteMeasurement report: A multi-year study on the impacts of Chinese New Year celebrations on air quality in Beijing, ChinaMixing state of black carbon at different atmospheres in north and southwest ChinaColumnar and surface urban aerosol in the Moscow megacity according to measurements and simulations with the COSMO-ART modelVertical aerosol particle exchange in the marine boundary layer estimated from helicopter-borne measurements in the Azores regionCircum-Antarctic abundance and properties of CCN and INPsThe ice-nucleating activity of African mineral dust in the Caribbean boundary layerBiomass burning and marine aerosol processing over the southeast Atlantic Ocean: a TEM single-particle analysisVolatility parameterization of ambient organic aerosols at a rural site of the North China PlainLight absorption by brown carbon over the South-East Atlantic OceanParticle size distribution and particulate matter concentrations during synoptic and convective dust events in West TexasMeasurement of light-absorbing particles in surface snow of central and western Himalayan glaciers: spatial variability, radiative impacts, and potential source regionsSeasonal variations in fire conditions are important drivers in the trend of aerosol optical properties over the south-eastern AtlanticBlack carbon aerosol reductions during COVID-19 confinement quantified by aircraft measurements over EuropeDiurnal evolution of negative atmospheric ions above the boreal forest: from ground level to the free troposphereAbsorption enhancement of black carbon particles in a Mediterranean city and countryside: effect of particulate matter chemistry, ageing and trend analysisMeasurement report: High Arctic aerosol hygroscopicity at sub- and supersaturated conditions during spring and summerCharacterizing the hygroscopicity of growing particles in the Canadian Arctic summerMeasurement report: Distinct size dependence and diurnal variation in organic aerosol hygroscopicity, volatility, and cloud condensation nuclei activity at a rural site in the Pearl River Delta (PRD) region, China
Adelaide Dinoi, Daniel Gulli, Kay Weinhold, Ivano Ammoscato, Claudia R. Calidonna, Alfred Wiedensohler, and Daniele Contini
Atmos. Chem. Phys., 23, 2167–2181,Short summary
In this study, particle number size distribution analysis was performed with the purpose of characterizing new particle formation (NPF) events occurring in two areas of southern Italy over 5 years of measurements. The identification of NPF events produced different results in terms of frequency and seasonality. Some of the main variables involved in the process, the local atmospheric conditions in which the events occurred, and the role of the air masses were discussed and compared.
Zhibo Xie, Jiaoshi Zhang, Huaqiao Gui, Yang Liu, Bo Yang, Haosheng Dai, Hang Xiao, Douguo Zhang, Da-Ren Chen, and Jianguo Liu
Atmos. Chem. Phys., 23, 2079–2088,Short summary
The hygroscopic growth of single nanoparticles is important for hygroscopic characteristic analysis of atmospheric particles and for scientific studies involving atmospheric particles. Based on the hygroscopicity difference of subgroups of atmospheric nanoparticles, the classification and proportion analysis of atmospheric nanoparticles has been completed, which has potential significance in predicting the contribution of the atmospheric particulate hygroscopicity and particle growth mechanism.
Matthew Boyer, Diego Aliaga, Jakob Boyd Pernov, Hélène Angot, Lauriane L. J. Quéléver, Lubna Dada, Benjamin Heutte, Manuel Dall'Osto, David C. S. Beddows, Zoé Brasseur, Ivo Beck, Silvia Bucci, Marina Duetsch, Andreas Stohl, Tiia Laurila, Eija Asmi, Andreas Massling, Daniel Charles Thomas, Jakob Klenø Nøjgaard, Tak Chan, Sangeeta Sharma, Peter Tunved, Radovan Krejci, Hans Christen Hansson, Federico Bianchi, Katrianne Lehtipalo, Alfred Wiedensohler, Kay Weinhold, Markku Kulmala, Tuukka Petäjä, Mikko Sipilä, Julia Schmale, and Tuija Jokinen
Atmos. Chem. Phys., 23, 389–415,Short summary
The Arctic is a unique environment that is warming faster than other locations on Earth. We evaluate measurements of aerosol particles, which can influence climate, over the central Arctic Ocean for a full year and compare the data to land-based measurement stations across the Arctic. Our measurements show that the central Arctic has similarities to but also distinct differences from the stations further south. We note that this may change as the Arctic warms and sea ice continues to decline.
Christina Spitieri, Maria Gini, Martin Gysel-Beer, and Konstantinos Eleftheriadis
Atmos. Chem. Phys., 23, 235–249,Short summary
The paper provides insights into the hygroscopic properties and state of mixing of atmospheric aerosol through 1 year of measurements of key microphysical parameters in the suburbs of the most densely populated city of Greece, Athens, in the eastern Mediterranean, which is considered an important climate change hotspot. The results can be used for the prediction of cloud condensation nuclei and quantification of the influence of ambient relative humidity on light scattering by aerosol particles.
Suzanne Crumeyrolle, Jenni S. S. Kontkanen, Clémence Rose, Alejandra Velazquez Garcia, Eric Bourrianne, Maxime Catalfamo, Véronique Riffault, Emmanuel Tison, Joel Ferreira de Brito, Nicolas Visez, Nicolas Ferlay, Frédérique Auriol, and Isabelle Chiapello
Atmos. Chem. Phys., 23, 183–201,Short summary
Ultrafine particles (UFPs) are particles with an aerodynamic diameter of 100 nm or less and negligible mass concentration but are the dominant contributor to the total particle number concentration. The present study aims to better understand the environmental factors favoring or inhibiting atmospheric new particle formation (NPF) over Lille, a large city in the north of France, and to analyze the impact of such an event on urban air quality using a long-term dataset (3 years).
Spiro D. Jorga, Kalliopi Florou, David Patoulias, and Spyros N. Pandis
Atmos. Chem. Phys., 23, 85–97,Short summary
We take advantage of this unexpected low, new particle formation frequency in Greece and use a dual atmospheric simulation chamber system with starting point ambient air in an effort to gain insight about the chemical species that is limiting nucleation in this area. A potential nucleation precursor, ammonia, was added in one of the chambers while the other one was used as a reference. The addition of ammonia assisted new particle formation in almost 50 % of the experiments conducted.
Allison B. Marquardt Collow, Virginie Buchard, Peter R. Colarco, Arlindo M. da Silva, Ravi Govindaraju, Edward P. Nowottnick, Sharon Burton, Richard Ferrare, Chris Hostetler, and Luke Ziemba
Atmos. Chem. Phys., 22, 16091–16109,Short summary
Biomass burning aerosol impacts aspects of the atmosphere and Earth system through radiative forcing, serving as cloud condensation nuclei, and air quality. Despite its importance, the representation of biomass burning aerosol is not always accurate in models. Field campaign observations from CAMP2Ex are used to evaluate the mass and extinction of aerosols in the GEOS model. Notable biases in the model illuminate areas of future development with GEOS and the underlying GOCART aerosol module.
Noah S. Hirshorn, Lauren M. Zuromski, Christopher Rapp, Ian McCubbin, Gerardo Carrillo-Cardenas, Fangqun Yu, and A. Gannet Hallar
Atmos. Chem. Phys., 22, 15909–15924,Short summary
New particle formation (NPF) is a source of atmospheric aerosol number concentration that can impact climate by growing to larger sizes and under proper conditions form cloud condensation nuclei (CCN). Using novel methods, we find that at Storm Peak Laboratory, a remote, mountaintop site in Colorado, NPF is observed to enhance CCN concentrations in the spring by a factor of 1.54 and in the winter by a factor of 1.36 which can occur on a regional scale having important climate implications.
Yuan Wang, Silvia Henning, Laurent Poulain, Chunsong Lu, Frank Stratmann, Yuying Wang, Shengjie Niu, Mira L. Pöhlker, Hartmut Herrmann, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 15943–15962,Short summary
Aerosol particle activation affects cloud, precipitation, radiation, and thus the global climate. Its long-term measurements are important but still scarce. In this study, more than 4 years of measurements at a central European station were analyzed. The overall characteristics and seasonal changes of aerosol particle activation are summarized. The power-law fit between particle hygroscopicity factor and diameter was recommended for predicting cloud condensation nuclei number concentration.
Juha Sulo, Janne Lampilahti, Xuemeng Chen, Jenni Kontkanen, Tuomo Nieminen, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Katrianne Lehtipalo
Atmos. Chem. Phys., 22, 15223–15242,Short summary
We measured atmospheric ion concentrations continuously in a boreal forest between 2005 and 2021 and observed an increasing interannual trend. The increase in cluster ion concentrations can be largely explained by an overall decreasing level of anthropogenic aerosols in the boreal forest. This suggests that the role of ions in atmospheric new particle formation may be more important in the future.
Liang Yuan and Chunsheng Zhao
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Chemical compositions variy between and within particles due to the complex sources and aging processes, causing particle-to-particle heterogeneity in aerosol hygroscopicity, which is of great importance to aerosol climatic and environmental effects. This study proposes an algorithm to quantify the heterogeneity from in-situ measurements, providing a framework for merging observation into numerical model to investigate how the heterogeneity influences aerosol impacts on climate and environment.
Rui Zhang, Yuying Wang, Zhanqing Li, Zhibin Wang, Russell R. Dickerson, Xinrong Ren, Hao He, Fei Wang, Ying Gao, Xi Chen, Jialu Xu, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 22, 14879–14891,Short summary
Factors of cloud condensation nuclei number concentration (NCCN) profiles determined in the North China Plain include air mass sources, temperature structure, anthropogenic emissions, and terrain distribution. Cloud condensation nuclei (CCN) spectra suggest that the ability of aerosol activation into CCN is stronger in southeasterly than in northwesterly air masses and stronger in the free atmosphere than near the surface. A good method to parameterize NCCN from aerosol optical data is found.
Nikou Hamzehpour, Claudia Marcolli, Sara Pashai, Kristian Klumpp, and Thomas Peter
Atmos. Chem. Phys., 22, 14905–14930,Short summary
Playa surfaces in Iran that emerged through Lake Urmia (LU) desiccation have become a relevant dust source of regional relevance. Here, we identify highly erodible LU playa surfaces and determine their physicochemical properties and mineralogical composition and perform emulsion-freezing experiments with them. We find high ice nucleation activities (up to 250 K) that correlate positively with organic matter and clay content and negatively with pH, salinity, K-feldspars, and quartz.
Payton Beeler and Rajan K. Chakrabarty
Atmos. Chem. Phys., 22, 14825–14836,Short summary
Understanding and parameterizing the influences of black carbon (BC) particle morphology and compositional heterogeneity on its light absorption represent a fundamental problem. We develop scaling laws using a single unifying parameter that effectively encompasses large-scale diversity observed in BC light absorption on a per-particle basis. The laws help reconcile the disparities between field observations and model predictions. Our framework is packaged in an open-source Python application.
Runlong Cai, Chenjuan Deng, Dominik Stolzenburg, Chenxi Li, Junchen Guo, Veli-Matti Kerminen, Jingkun Jiang, Markku Kulmala, and Juha Kangasluoma
Atmos. Chem. Phys., 22, 14571–14587,Short summary
The survival probability of new particles is the key parameter governing their influences on the atmosphere and climate, yet the knowledge of particle survival in the atmosphere is rather limited. We propose methods to compute the size-resolved particle survival probability and validate them using simulations and measurements from diverse environments. Using these methods, we could explain particle survival from the cluster size to the cloud condensation nuclei size.
Guangyu Li, Jörg Wieder, Julie T. Pasquier, Jan Henneberger, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 14441–14454,Short summary
The concentration of ice-nucleating particles (INPs) is atmospherically relevant for primary ice formation in clouds. In this work, from 12 weeks of field measurement data in the Arctic, we developed a new parameterization to predict INP concentrations applicable for pristine background conditions based only on temperature. The INP parameterization could improve the cloud microphysical representation in climate models, aiding in Arctic climate predictions.
Yuying Wang, Rong Hu, Qiuyan Wang, Zhanqing Li, Maureen Cribb, Yele Sun, Xiaorui Song, Yi Shang, Yixuan Wu, Xin Huang, and Yuxiang Wang
Atmos. Chem. Phys., 22, 14133–14146,Short summary
The mixing state of size-resolved soot particles and their influencing factors were investigated. The results suggest anthropogenic emissions and aging processes have diverse impacts on the mixing state of soot particles in different modes. Considering that the mixing state of soot particles is crucial to model aerosol absorption, this finding is important to study particle growth and the warming effect of black carbon aerosols.
Xiaoying Niu, Wei Pu, Pingqing Fu, Yang Chen, Yuxuan Xing, Dongyou Wu, Ziqi Chen, Tenglong Shi, Yue Zhou, Hui Wen, and Xin Wang
Atmos. Chem. Phys., 22, 14075–14094,Short summary
In this study, we do the first investigation of WSOC in seasonal snow of northeastern China. The results revealed the regional-specific compositions and sources of WSOC due to different natural environments and anthropogenic activities. The abundant concentrations of WSOC and its absorption properties contributed to a crucial impact on the snow albedo and radiative effect. We established that our study could raise awareness of carbon cycling processes, hydrological processes, and climate change.
Chenjuan Deng, Yiran Li, Chao Yan, Jin Wu, Runlong Cai, Dongbin Wang, Yongchun Liu, Juha Kangasluoma, Veli-Matti Kerminen, Markku Kulmala, and Jingkun Jiang
Atmos. Chem. Phys., 22, 13569–13580,Short summary
The size distributions of urban atmospheric particles convey important information on their origins and impacts. This study investigates the characteristics of typical particle size distributions and key gaseous precursors in the long term in urban Beijing. A fitting function is proposed to represent and help interpret size distribution including particles and gaseous precursors. In addition to NPF (new particle formation) as the major source, vehicles can emit sub-3 nm particles as well
Qian Liu, Guixing Chen, Lifang Sheng, and Toshiki Iwasaki
Atmos. Chem. Phys., 22, 13371–13388,Short summary
Air pollution can be cleaned up quickly by a cold air outbreak (CAO) but reappears after a CAO. By quantifying the CAO properties, we find the coldness and depth of the cold air mass are key factors affecting the rapid (slow) reappearance of air pollution through modulating the atmospheric boundary layer height and stability. We also find that the spatial pattern of CAO in high-latitude Eurasia a few days ahead can be recognized as a precursor for the reappearance of air pollution.
Loïc Gonzalez Carracedo, Katrianne Lehtipalo, Lauri R. Ahonen, Nina Sarnela, Sebastian Holm, Juha Kangasluoma, Markku Kulmala, Paul M. Winkler, and Dominik Stolzenburg
Atmos. Chem. Phys., 22, 13153–13166,Short summary
Fast nanoparticle growth is essential for the survival of new aerosol particles in the atmosphere and hence their contribution to the climate. We show that using naturally charged ions for growth calculations can cause a significant error. During the diurnal cycle, the importance of ion-induced and neutral nucleation varies, causing the ion population to have a slower measurable apparent growth. Results suggest that data from ion spectrometers need to be considered with great care below 3 nm.
Eva-Lou Edwards, Jeffrey S. Reid, Peng Xian, Sharon P. Burton, Anthony L. Cook, Ewan C. Crosbie, Marta A. Fenn, Richard A. Ferrare, Sean W. Freeman, John W. Hair, David B. Harper, Chris A. Hostetler, Claire E. Robinson, Amy Jo Scarino, Michael A. Shook, G. Alexander Sokolowsky, Susan C. van den Heever, Edward L. Winstead, Sarah Woods, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 22, 12961–12983,Short summary
This study compares NAAPS-RA model simulations of aerosol optical thickness (AOT) and extinction to those retrieved with a high spectral resolution lidar near the Philippines. Agreement for AOT was good, and extinction agreement was strongest below 1500 m. Substituting dropsonde relative humidities into NAAPS-RA did not drastically improve agreement, and we discuss potential reasons why. Accurately modeling future conditions in this region is crucial due to its susceptibility to climate change.
Ville Leinonen, Harri Kokkola, Taina Yli-Juuti, Tero Mielonen, Thomas Kühn, Tuomo Nieminen, Simo Heikkinen, Tuuli Miinalainen, Tommi Bergman, Ken Carslaw, Stefano Decesari, Markus Fiebig, Tareq Hussein, Niku Kivekäs, Radovan Krejci, Markku Kulmala, Ari Leskinen, Andreas Massling, Nikos Mihalopoulos, Jane P. Mulcahy, Steffen M. Noe, Twan van Noije, Fiona M. O'Connor, Colin O'Dowd, Dirk Olivie, Jakob B. Pernov, Tuukka Petäjä, Øyvind Seland, Michael Schulz, Catherine E. Scott, Henrik Skov, Erik Swietlicki, Thomas Tuch, Alfred Wiedensohler, Annele Virtanen, and Santtu Mikkonen
Atmos. Chem. Phys., 22, 12873–12905,Short summary
We provide the first extensive comparison of detailed aerosol size distribution trends between in situ observations from Europe and five different earth system models. We investigated aerosol modes (nucleation, Aitken, and accumulation) separately and were able to show the differences between measured and modeled trends and especially their seasonal patterns. The differences in model results are likely due to complex effects of several processes instead of certain specific model features.
Nicole A. June, Anna L. Hodshire, Elizabeth B. Wiggins, Edward L. Winstead, Claire E. Robinson, K. Lee Thornhill, Kevin J. Sanchez, Richard H. Moore, Demetrios Pagonis, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Matthew M. Coggon, Jonathan M. Dean-Day, T. Paul Bui, Jeff Peischl, Robert J. Yokelson, Matthew J. Alvarado, Sonia M. Kreidenweis, Shantanu H. Jathar, and Jeffrey R. Pierce
Atmos. Chem. Phys., 22, 12803–12825,Short summary
The evolution of organic aerosol composition and size is uncertain due to variability within and between smoke plumes. We examine the impact of plume concentration on smoke evolution from smoke plumes sampled by the NASA DC-8 during FIREX-AQ. We find that observed organic aerosol and size distribution changes are correlated to plume aerosol mass concentrations. Additionally, coagulation explains the majority of the observed growth.
Francesca Gallo, Janek Uin, Kevin J. Sanchez, Richard H. Moore, Jian Wang, Robert Wood, Fan Mei, Connor Flynn, Stephen Springston, Eduardo B. Azevedo, Chongai Kuang, and Allison C. Aiken
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
This study provides a summary statistic of multiday aerosol plume transport events influences on aerosol physical properties and cloud condensation nuclei budget at the U.S. Department of Energy Atmospheric Radiation Measurement Facility in the Eastern North Atlantic (ENA). An algorithm that integrates aerosol properties is developed and applied to identify multiday aerosol transport events. The influence of the aerosol plumes on aerosol populations at ENA is successively assessed.
Ruiqi Man, Zhijun Wu, Taomou Zong, Aristeidis Voliotis, Yanting Qiu, Johannes Größ, Dominik van Pinxteren, Limin Zeng, Hartmut Herrmann, Alfred Wiedensohler, and Min Hu
Atmos. Chem. Phys., 22, 12387–12399,Short summary
Regional and total deposition doses for different age groups were quantified based on explicit hygroscopicity measurements. We found that particle hygroscopic growth led to a reduction (~24 %) in the total dose. The deposition rate of hygroscopic particles was higher in the daytime, while hydrophobic particles exhibited a higher rate at night and during rush hours. The results will deepen the understanding of the impact of hygroscopicity and the mixing state on deposition patterns in the lungs.
Biao Luo, Ye Kuang, Shan Huang, Qicong Song, Weiwei Hu, Wei Li, Yuwen Peng, Duohong Chen, Dingli Yue, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 22, 12401–12415,Short summary
We performed comprehensive analysis on biomass burning organic aerosol (BBOA) size distributions, as well as mass scattering and absorption efficiencies, with an improved method of on-line quantification of brown carbon absorptions. Both BBOA volume size distribution and retrieved refractive index depend highly on combustion conditions represented by the black carbon content, which has significant implications for BBOA climate effect simulations.
Outi Meinander, Pavla Dagsson-Waldhauserova, Pavel Amosov, Elena Aseyeva, Cliff Atkins, Alexander Baklanov, Clarissa Baldo, Sarah L. Barr, Barbara Barzycka, Liane G. Benning, Bojan Cvetkovic, Polina Enchilik, Denis Frolov, Santiago Gassó, Konrad Kandler, Nikolay Kasimov, Jan Kavan, James King, Tatyana Koroleva, Viktoria Krupskaya, Markku Kulmala, Monika Kusiak, Hanna K. Lappalainen, Michał Laska, Jerome Lasne, Marek Lewandowski, Bartłomiej Luks, James B. McQuaid, Beatrice Moroni, Benjamin Murray, Ottmar Möhler, Adam Nawrot, Slobodan Nickovic, Norman T. O’Neill, Goran Pejanovic, Olga Popovicheva, Keyvan Ranjbar, Manolis Romanias, Olga Samonova, Alberto Sanchez-Marroquin, Kerstin Schepanski, Ivan Semenkov, Anna Sharapova, Elena Shevnina, Zongbo Shi, Mikhail Sofiev, Frédéric Thevenet, Throstur Thorsteinsson, Mikhail Timofeev, Nsikanabasi Silas Umo, Andreas Uppstu, Darya Urupina, György Varga, Tomasz Werner, Olafur Arnalds, and Ana Vukovic Vimic
Atmos. Chem. Phys., 22, 11889–11930,Short summary
High-latitude dust (HLD) is a short-lived climate forcer, air pollutant, and nutrient source. Our results suggest a northern HLD belt at 50–58° N in Eurasia and 50–55° N in Canada and at >60° N in Eurasia and >58° N in Canada. Our addition to the previously identified global dust belt (GDB) provides crucially needed information on the extent of active HLD sources with both direct and indirect impacts on climate and environment in remote regions, which are often poorly understood and predicted.
Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, James Harnwell, Simon P. Alexander, Andrew R. Klekociuk, Keiichiro Hara, Ian M. McRobert, Alain Protat, Joel Alroe, Luke T. Cravigan, Branka Miljevic, Zoran D. Ristovski, Robyn Schofield, Stephen R. Wilson, Connor J. Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Greg M. McFarquhar, Scott D. Chambers, Alastair G. Williams, and Alan D. Griffiths
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Observations of aerosols in pristine regions are rare, but are vital to constraining the natural baseline from which climate simulations are calculated. Here we present recent seasonal observations of aerosols from the Southern Ocean and contrast them with measurements from Antarctica, Australia, and regionally relevant voyages. Strong seasonal cycles persist, but striking differences occur at different latitudes. This study highlights the need for more long-term observations in remote regions.
Haichao Wang, Yongbo Tan, Zheng Shi, Ning Yang, and Tianxue Zheng
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
The effects of aerosols on lightning are complex and still far from understood. We analysed the difference in the impacts of aerosols on lightning activity between daytime and nighttime in the Sichuan Basin. Results show that aerosols have no evident effects on lightning activity in the daytime, but tend to invigorate it in the nighttime. These results suggest that aerosols play different roles in the occurrence and development of convection and lightning activity between daytime and nighttime.
Samuel E. LeBlanc, Michal Segal-Rozenhaimer, Jens Redemann, Connor Flynn, Roy R. Johnson, Stephen E. Dunagan, Robert Dahlgren, Jhoon Kim, Myungje Choi, Arlindo da Silva, Patricia Castellanos, Qian Tan, Luke Ziemba, Kenneth Lee Thornhill, and Meloë Kacenelenbogen
Atmos. Chem. Phys., 22, 11275–11304,Short summary
Airborne observations of atmospheric particles and pollution over Korea during a field campaign in May–June 2016 showed that the smallest atmospheric particles are present in the lowest 2 km of the atmosphere. The aerosol size is more spatially variable than optical thickness. We show this with remote sensing (4STAR), in situ (LARGE) observations, satellite measurements (GOCI), and modeled properties (MERRA-2), and it is contrary to the current understanding.
Jerome D. Fast, David M. Bell, Gourihar Kulkarni, Jiumeng Liu, Fan Mei, Georges Saliba, John E. Shilling, Kaitlyn Suski, Jason Tomlinson, Jian Wang, Rahul Zaveri, and Alla Zelenyuk
Atmos. Chem. Phys., 22, 11217–11238,Short summary
Recent aircraft measurements from the HI-SCALE campaign conducted over the Southern Great Plains (SGP) site in Oklahoma are used to quantify spatial variability of aerosol properties in terms of grid spacings typically used by weather and climate models. Surprisingly large horizontal gradients in aerosol properties were frequently observed in this rural area. This spatial variability can be used as an uncertainty range when comparing surface point measurements with model predictions.
Benjamin Foreback, Lubna Dada, Kaspar R. Daellenbach, Chao Yan, Lili Wang, Biwu Chu, Ying Zhou, Tom V. Kokkonen, Mona Kurppa, Rosaria E. Pileci, Yonghong Wang, Tommy Chan, Juha Kangasluoma, Lin Zhuohui, Yishou Guo, Chang Li, Rima Baalbaki, Joni Kujansuu, Xiaolong Fan, Zemin Feng, Pekka Rantala, Shahzad Gani, Federico Bianchi, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, Yongchun Liu, and Pauli Paasonen
Atmos. Chem. Phys., 22, 11089–11104,Short summary
This study analyzed air quality in Beijing during the Chinese New Year over 7 years, including data from a new in-depth measurement station. This is one of few studies to look at long-term impacts, including the outcome of firework restrictions starting in 2018. Results show that firework pollution has gone down since 2016, indicating a positive result from the restrictions. Results of this study may be useful in making future decisions about the use of fireworks to improve air quality.
Gang Zhao, Tianyi Tan, Shuya Hu, Zhuofei Du, Dongjie Shang, Zhijun Wu, Song Guo, Jing Zheng, Wenfei Zhu, Mengren Li, Limin Zeng, and Min Hu
Atmos. Chem. Phys., 22, 10861–10873,Short summary
Black carbon is the second strongest absorbing component in the atmosphere that exerts warming effects on climate. One critical challenge in quantifying the ambient black carbon's radiative effects is addressing the BC microphysical properties. In this study, the microphysical properties of the aged and fresh BC particles are synthetically analyzed under different atmospheres. The measurement results can be further used in models to help constrain the uncertainties of the BC radiative effects.
Natalia E. Chubarova, Heike Vogel, Elizaveta E. Androsova, Alexander A. Kirsanov, Olga B. Popovicheva, Bernhard Vogel, and Gdaliy S. Rivin
Atmos. Chem. Phys., 22, 10443–10466,Short summary
Effects of urban aerosol pollution in Moscow were analyzed using the COSMO-ART chemical transport model and intensive measurement campaigns. We show that urban aerosol comprises about 15–20% of columnar aerosol content, consisting mainly of fine aerosol mode. The black carbon (BC) fraction is about 5 %, depending on particle dispersion intensity (IPD). The BC fraction low value explains weak absorbing properties of the Moscow atmosphere. IPD also defines the daily cycle of urban aerosol species.
Janine Lückerath, Andreas Held, Holger Siebert, Michel Michalkow, and Birgit Wehner
Atmos. Chem. Phys., 22, 10007–10021,Short summary
Three different methods were applied to estimate the vertical aerosol particle flux in the marine boundary layer (MBL) and between the MBL and free troposphere. For the first time, aerosol fluxes derived from these three methods were estimated and compared using airborne aerosol measurements using data from the ACORES field campaign in the northeastern Atlantic Ocean in July 2017. The amount of fluxes was small and directed up and down for different cases, but the methods were applicable.
Christian Tatzelt, Silvia Henning, André Welti, Andrea Baccarini, Markus Hartmann, Martin Gysel-Beer, Manuela van Pinxteren, Robin L. Modini, Julia Schmale, and Frank Stratmann
Atmos. Chem. Phys., 22, 9721–9745,Short summary
We present the abundance and origin of cloud-relevant aerosol particles in the preindustral-like conditions of the Southern Ocean (SO) during austral summer. Cloud condensation nuclei (CCN) and ice-nucleating particles (INP) were measured during a circum-Antarctic scientific cruise with in situ instrumentation and offline filter measurements, respectively. Transport processes were found to play an equally important role as local sources for both the CCN and INP population of the SO.
Alexander D. Harrison, Daniel O'Sullivan, Michael P. Adams, Grace C. E. Porter, Edmund Blades, Cherise Brathwaite, Rebecca Chewitt-Lucas, Cassandra Gaston, Rachel Hawker, Ovid O. Krüger, Leslie Neve, Mira L. Pöhlker, Christopher Pöhlker, Ulrich Pöschl, Alberto Sanchez-Marroquin, Andrea Sealy, Peter Sealy, Mark D. Tarn, Shanice Whitehall, James B. McQuaid, Kenneth S. Carslaw, Joseph M. Prospero, and Benjamin J. Murray
Atmos. Chem. Phys., 22, 9663–9680,Short summary
The formation of ice in clouds fundamentally alters cloud properties; hence it is important we understand the special aerosol particles that can nucleate ice when immersed in supercooled cloud droplets. In this paper we show that African desert dust that has travelled across the Atlantic to the Caribbean nucleates ice much less well than we might have expected.
Caroline Dang, Michal Segal-Rozenhaimer, Haochi Che, Lu Zhang, Paola Formenti, Jonathan Taylor, Amie Dobracki, Sara Purdue, Pui-Shan Wong, Athanasios Nenes, Arthur Sedlacek III, Hugh Coe, Jens Redemann, Paquita Zuidema, Steven Howell, and James Haywood
Atmos. Chem. Phys., 22, 9389–9412,Short summary
Transmission electron microscopy was used to analyze aged African smoke particles and how the smoke interacts with the marine atmosphere. We found that the volatility of organic aerosol increases with biomass burning plume age, that black carbon is often mixed with potassium salts and that the marine atmosphere can incorporate Na and Cl into smoke particles. Marine salts are more processed when mixed with smoke plumes, and there are interesting Cl-rich yet Na-absent marine particles.
Siman Ren, Lei Yao, Yuwei Wang, Gan Yang, Yiliang Liu, Yueyang Li, Yiqun Lu, Lihong Wang, and Lin Wang
Atmos. Chem. Phys., 22, 9283–9297,Short summary
We improved the empirical functions between volatility and chemical formulas of organic aerosols based on lab experiments and field observations. It was found that organic compounds in ambient aerosols can be divided into two groups according to their O / C ratios and that there should be specialized volatility parameterizations for different O / C organic compounds.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Arthur J. Sedlacek III, Ernie R. Lewis, Amie Dobracki, Jenny P. S. Wong, Paola Formenti, Steven G. Howell, and Athanasios Nenes
Atmos. Chem. Phys., 22, 9199–9213,Short summary
Widespread biomass burning (BB) events occur annually in Africa and contribute ~ 1 / 3 of global BB emissions, which contain a large family of light-absorbing organics, known as brown carbon (BrC), whose absorption of incident radiation is difficult to estimate, leading to large uncertainties in the global radiative forcing estimation. This study quantifies the BrC absorption of aged BB particles and highlights the potential presence of absorbing iron oxides in this climatically important region.
Karin Ardon-Dryer and Mary C. Kelley
Atmos. Chem. Phys., 22, 9161–9173,Short summary
Changes in the particle size distribution and particulate matter concentrations during different dust events in West Texas were examined. Analysis based on different timescales showed that current common methods used to evaluate the impact of dust events on air quality will not capture the true impact of short (convective) dust events and, therefore, do not provide an insightful understanding of their impact on the environment and human health.
Chaman Gul, Shichang Kang, Siva Praveen Puppala, Xiaokang Wu, Cenlin He, Yangyang Xu, Inka Koch, Sher Muhammad, Rajesh Kumar, and Getachew Dubache
Atmos. Chem. Phys., 22, 8725–8737,Short summary
This work aims to understand concentrations, spatial variability, and potential source regions of light-absorbing impurities (black carbon aerosols, dust particles, and organic carbon) in the surface snow of central and western Himalayan glaciers and their impact on snow albedo and radiative forcing.
Haochi Che, Michal Segal-Rozenhaimer, Lu Zhang, Caroline Dang, Paquita Zuidema, Arthur J. Sedlacek III, Xiaoye Zhang, and Connor Flynn
Atmos. Chem. Phys., 22, 8767–8785,Short summary
A 17-month in situ study on Ascension Island found low single-scattering albedo and strong absorption enhancement of the marine boundary layer aerosols during biomass burnings on the African continent, along with apparent patterns of regular monthly variability. We further discuss the characteristics and drivers behind these changes and find that biomass burning conditions in Africa may be the main factor influencing the optical properties of marine boundary aerosols.
Ovid O. Krüger, Bruna A. Holanda, Sourangsu Chowdhury, Andrea Pozzer, David Walter, Christopher Pöhlker, Maria Dolores Andrés Hernández, John P. Burrows, Christiane Voigt, Jos Lelieveld, Johannes Quaas, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 22, 8683–8699,Short summary
The abrupt reduction in human activities during the first COVID-19 lockdown created unprecedented atmospheric conditions. We took the opportunity to quantify changes in black carbon (BC) as a major anthropogenic air pollutant. Therefore, we measured BC on board a research aircraft over Europe during the lockdown and compared the results to measurements from 2017. With model simulations we account for different weather conditions and find a lockdown-related decrease in BC of 41 %.
Lisa J. Beck, Siegfried Schobesberger, Heikki Junninen, Janne Lampilahti, Antti Manninen, Lubna Dada, Katri Leino, Xu-Cheng He, Iida Pullinen, Lauriane L. J. Quéléver, Anna Franck, Pyry Poutanen, Daniela Wimmer, Frans Korhonen, Mikko Sipilä, Mikael Ehn, Douglas R. Worsnop, Veli-Matti Kerminen, Tuukka Petäjä, Markku Kulmala, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 8547–8577,Short summary
The presented article introduces an overview of atmospheric ions and their composition above the boreal forest. We provide the results of an extensive airborne measurement campaign with an air ion mass spectrometer and particle measurements, showing their diurnal evolution within the boundary layer and free troposphere. In addition, we compare the airborne dataset with the co-located data from the ground at SMEAR II station, Finland.
Jesús Yus-Díez, Marta Via, Andrés Alastuey, Angeliki Karanasiou, María Cruz Minguillón, Noemí Perez, Xavier Querol, Cristina Reche, Matic Ivančič, Martin Rigler, and Marco Pandolfi
Atmos. Chem. Phys., 22, 8439–8456,Short summary
This study presents the absorption enhancement of internally and externally mixed black carbon (BC) particles in a Mediterranean city and countryside. We showed the importance of secondary organic aerosols (SOAs) and particle ageing by increasing the BC absorption enhancement. We performed a trend analysis on the absorption enhancement. We found a positive trend of the absorption enhancement at the regional station in summer driven by the increase over time of the relative contribution of SOA.
Andreas Massling, Robert Lange, Jakob Pernov, Ulrich Gosewinkel, Lise-Lotte Sørensen, and Henrik Skov
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
The effect of anthropogenic activities on cloud formation introduces the highest uncertainties with respect to climate change. Data on Arctic aerosols and their corresponding cloud-forming properties are very scarce and most important as the Arctic is warming about two times as fast as the rest of the globe. Our studies investigate aerosols in the remote Arctic and suggest relatively high cloud-forming potential, although differences are observed between the Arctic spring and summer.
Rachel Y.-W. Chang, Jonathan P. D. Abbatt, Matthew C. Boyer, Jai Prakash Chaubey, and Douglas B. Collins
Atmos. Chem. Phys., 22, 8059–8071,Short summary
During summer 2016, the ability of newly formed particles to turn into droplets was measured in the Canadian Arctic. Our observations suggest that these small particles were growing by the condensation of organic vapours likely coming from the surrounding open waters. These particles grew large enough that they could form cloud droplets and therefore affect the earth’s radiation budget. These results are relevant as the Arctic summer rapidly warms with climate change.
Mingfu Cai, Shan Huang, Baoling Liang, Qibin Sun, Li Liu, Bin Yuan, Min Shao, Weiwei Hu, Wei Chen, Qicong Song, Wei Li, Yuwen Peng, Zelong Wang, Duohong Chen, Haobo Tan, Hanbin Xu, Fei Li, Xuejiao Deng, Tao Deng, Jiaren Sun, and Jun Zhao
Atmos. Chem. Phys., 22, 8117–8136,Short summary
This study investigated the size dependence and diurnal variation in organic aerosol hygroscopicity, volatility, and cloud condensation nuclei (CCN) activity. We found that the physical properties of OA could vary in a large range at different particle sizes and affected the number concentration of CCN (NCCN) at all supersaturations. Our results highlight the importance of evaluating the atmospheric evolution processes of OA at different size ranges and their impact on climate effects.
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