Articles | Volume 14, issue 21
https://doi.org/10.5194/acp-14-11883-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-14-11883-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
12 Nov 2014
Research article |
| 12 Nov 2014
Assessment and application of clustering techniques to atmospheric particle number size distribution for the purpose of source apportionment
F. Salimi
International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane QLD, 4001, Australia
Z. Ristovski
International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane QLD, 4001, Australia
M. Mazaheri
International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane QLD, 4001, Australia
R. Laiman
International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane QLD, 4001, Australia
L. R. Crilley
International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane QLD, 4001, Australia
now at: School of Geography, Earth and Environmental Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
C. He
International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane QLD, 4001, Australia
S. Clifford
International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane QLD, 4001, Australia
International Laboratory for Air Quality and Health, Queensland University of Technology, GPO Box 2434, Brisbane QLD, 4001, Australia
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Atmos. Chem. Phys., 23, 5679–5697, https://doi.org/10.5194/acp-23-5679-2023, https://doi.org/10.5194/acp-23-5679-2023, 2023
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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., 23, 3749–3777, https://doi.org/10.5194/acp-23-3749-2023, https://doi.org/10.5194/acp-23-3749-2023, 2023
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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.
Teles C. Furlani, RenXi Ye, Jordan Stewart, Leigh R. Crilley, Peter M. Edwards, Tara F. Kahan, and Cora J. Young
Atmos. Meas. Tech., 16, 181–193, https://doi.org/10.5194/amt-16-181-2023, https://doi.org/10.5194/amt-16-181-2023, 2023
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Ülkü Alver Şahin, Roy M. Harrison, Mohammed S. Alam, David C. S. Beddows, Dimitrios Bousiotis, Zongbo Shi, Leigh R. Crilley, William Bloss, James Brean, Isha Khanna, and Rulan Verma
Atmos. Chem. Phys., 22, 5415–5433, https://doi.org/10.5194/acp-22-5415-2022, https://doi.org/10.5194/acp-22-5415-2022, 2022
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Wide-range particle size spectra have been measured in three seasons in Delhi and are interpreted in terms of sources and processes. Condensational growth is a major feature of the fine fraction, and a coarse fraction contributes substantially – but only in summer.
Robert Woodward-Massey, Roberto Sommariva, Lisa K. Whalley, Danny R. Cryer, Trevor Ingham, William J1 Bloss, Sam Cox, James D. Lee, Chris P. Reed, Leigh R. Crilley, Louisa J. Kramer, Brian J. Bandy, Grant L. Forster, Claire E. Reeves, Paul S. Monks, and Dwayne E. Heard
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Preprint withdrawn
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We measured radicals (OH, HO2, RO2) and OH reactivity at a UK coastal site and compared our observations to the predictions of an MCMv3.3.1 box model. We find variable agreement between measured and modelled radical concentrations and OH reactivity, where the levels of agreement for individual species display strong dependences on NO concentrations. The most substantial disagreement is found for RO2 at high NO (> 1 ppbv), when RO2 levels are underpredicted by a factor of ~10–30.
Sonya L. Fiddes, Matthew T. Woodhouse, Steve Utembe, Robyn Schofield, Simon P. Alexander, Joel Alroe, Scott D. Chambers, Zhenyi Chen, Luke Cravigan, Erin Dunne, Ruhi S. Humphries, Graham Johnson, Melita D. Keywood, Todd P. Lane, Branka Miljevic, Yuko Omori, Alain Protat, Zoran Ristovski, Paul Selleck, Hilton B. Swan, Hiroshi Tanimoto, Jason P. Ward, and Alastair G. Williams
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Leigh R. Crilley, Louisa J. Kramer, Francis D. Pope, Chris Reed, James D. Lee, Lucy J. Carpenter, Lloyd D. J. Hollis, Stephen M. Ball, and William J. Bloss
Atmos. Chem. Phys., 21, 18213–18225, https://doi.org/10.5194/acp-21-18213-2021, https://doi.org/10.5194/acp-21-18213-2021, 2021
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Nitrous acid (HONO) is a key source of atmospheric oxidants. We evaluate if the ocean surface is a source of HONO for the marine boundary layer, using measurements from two contrasting coastal locations. We observed no evidence for a night-time ocean surface source, in contrast to previous work. This points to significant geographical variation in the predominant HONO formation mechanisms in marine environments, reflecting possible variability in the sea-surface microlayer composition.
Beth S. Nelson, Gareth J. Stewart, Will S. Drysdale, Mike J. Newland, Adam R. Vaughan, Rachel E. Dunmore, Pete M. Edwards, Alastair C. Lewis, Jacqueline F. Hamilton, W. Joe Acton, C. Nicholas Hewitt, Leigh R. Crilley, Mohammed S. Alam, Ülkü A. Şahin, David C. S. Beddows, William J. Bloss, Eloise Slater, Lisa K. Whalley, Dwayne E. Heard, James M. Cash, Ben Langford, Eiko Nemitz, Roberto Sommariva, Sam Cox, Shivani, Ranu Gadi, Bhola R. Gurjar, James R. Hopkins, Andrew R. Rickard, and James D. Lee
Atmos. Chem. Phys., 21, 13609–13630, https://doi.org/10.5194/acp-21-13609-2021, https://doi.org/10.5194/acp-21-13609-2021, 2021
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Ozone production at an urban site in Delhi is sensitive to volatile organic compound (VOC) concentrations, particularly those of the aromatic, monoterpene, and alkene VOC classes. The change in ozone production by varying atmospheric pollutants according to their sources, as defined in an emissions inventory, is investigated. The study suggests that reducing road transport emissions alone does not reduce reactive VOCs in the atmosphere enough to perturb an increase in ozone production.
Ernesto Reyes-Villegas, Upasana Panda, Eoghan Darbyshire, James M. Cash, Rutambhara Joshi, Ben Langford, Chiara F. Di Marco, Neil J. Mullinger, Mohammed S. Alam, Leigh R. Crilley, Daniel J. Rooney, W. Joe F. Acton, Will Drysdale, Eiko Nemitz, Michael Flynn, Aristeidis Voliotis, Gordon McFiggans, Hugh Coe, James Lee, C. Nicholas Hewitt, Mathew R. Heal, Sachin S. Gunthe, Tuhin K. Mandal, Bhola R. Gurjar, Shivani, Ranu Gadi, Siddhartha Singh, Vijay Soni, and James D. Allan
Atmos. Chem. Phys., 21, 11655–11667, https://doi.org/10.5194/acp-21-11655-2021, https://doi.org/10.5194/acp-21-11655-2021, 2021
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This paper shows the first multisite online measurements of PM1 in Delhi, India, with measurements over different seasons in Old Delhi and New Delhi in 2018. Organic aerosol (OA) source apportionment was performed using positive matrix factorisation (PMF). Traffic was the main primary aerosol source for both OAs and black carbon, seen with PMF and Aethalometer model analysis, indicating that control of primary traffic exhaust emissions would make a significant reduction to Delhi air pollution.
Claire E. Reeves, Graham P. Mills, Lisa K. Whalley, W. Joe F. Acton, William J. Bloss, Leigh R. Crilley, Sue Grimmond, Dwayne E. Heard, C. Nicholas Hewitt, James R. Hopkins, Simone Kotthaus, Louisa J. Kramer, Roderic L. Jones, James D. Lee, Yanhui Liu, Bin Ouyang, Eloise Slater, Freya Squires, Xinming Wang, Robert Woodward-Massey, and Chunxiang Ye
Atmos. Chem. Phys., 21, 6315–6330, https://doi.org/10.5194/acp-21-6315-2021, https://doi.org/10.5194/acp-21-6315-2021, 2021
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The impact of isoprene on atmospheric chemistry is dependent on how its oxidation products interact with other pollutants, specifically nitrogen oxides. Such interactions can lead to isoprene nitrates. We made measurements of the concentrations of individual isoprene nitrate isomers in Beijing and used a model to test current understanding of their chemistry. We highlight areas of uncertainty in understanding, in particular the chemistry following oxidation of isoprene by the nitrate radical.
Lisa K. Whalley, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Archit Mehra, Stephen D. Worrall, Asan Bacak, Thomas J. Bannan, Hugh Coe, Carl J. Percival, Bin Ouyang, Roderic L. Jones, Leigh R. Crilley, Louisa J. Kramer, William J. Bloss, Tuan Vu, Simone Kotthaus, Sue Grimmond, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 21, 2125–2147, https://doi.org/10.5194/acp-21-2125-2021, https://doi.org/10.5194/acp-21-2125-2021, 2021
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To understand how emission controls will impact ozone, an understanding of the sources and sinks of OH and the chemical cycling between peroxy radicals is needed. This paper presents measurements of OH, HO2 and total RO2 taken in central Beijing. The radical observations are compared to a detailed chemistry model, which shows that under low NO conditions, there is a missing OH source. Under high NOx conditions, the model under-predicts RO2 and impacts our ability to model ozone.
Eloise J. Slater, Lisa K. Whalley, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Leigh R. Crilley, Louisa Kramer, William Bloss, Tuan Vu, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 20, 14847–14871, https://doi.org/10.5194/acp-20-14847-2020, https://doi.org/10.5194/acp-20-14847-2020, 2020
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The paper details atmospheric chemistry in a megacity (Beijing), focussing on radicals which mediate the formation of secondary pollutants such as ozone and particles. Highly polluted conditions were experienced, including the highest ever levels of nitric oxide (NO), with simultaneous radical measurements. Radical concentrations were large during "haze" events, demonstrating active photochemistry. Modelling showed that our understanding of the chemistry at high NOx levels is incomplete.
Atallah Elzein, Gareth J. Stewart, Stefan J. Swift, Beth S. Nelson, Leigh R. Crilley, Mohammed S. Alam, Ernesto Reyes-Villegas, Ranu Gadi, Roy M. Harrison, Jacqueline F. Hamilton, and Alastair C. Lewis
Atmos. Chem. Phys., 20, 14303–14319, https://doi.org/10.5194/acp-20-14303-2020, https://doi.org/10.5194/acp-20-14303-2020, 2020
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We collected high-frequency air particle samples (PM2.5) in Beijing (China) and Delhi (India) and measured the concentration of PAHs in daytime and night-time. PAHs were higher in Delhi than in Beijing, and the five-ring PAHs contribute the most to the total PAH concentration. We compared the emission sources and identified the major sectors that could be subject to mitigation measures. The adverse health effects from inhalation exposure to PAHs in Delhi are 2.2 times higher than in Beijing.
Mohammed S. Alam, Leigh R. Crilley, James D. Lee, Louisa J. Kramer, Christian Pfrang, Mónica Vázquez-Moreno, Milagros Ródenas, Amalia Muñoz, and William J. Bloss
Atmos. Meas. Tech., 13, 5977–5991, https://doi.org/10.5194/amt-13-5977-2020, https://doi.org/10.5194/amt-13-5977-2020, 2020
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We report on the interference arising in measurements of nitrogen oxides (NOx) from the presence of a range of alkenes in sampled air when using the most widespread air quality monitoring technique for chemiluminescence detection. Interferences of up to 11 % are reported, depending upon the alkene present and conditions used. Such interferences may be of substantial importance for the interpretation of ambient NOx data, particularly for high volatile organic compound and low NOx environments.
Melodie Lao, Leigh R. Crilley, Leyla Salehpoor, Teles C. Furlani, Ilann Bourgeois, J. Andrew Neuman, Andrew W. Rollins, Patrick R. Veres, Rebecca A. Washenfelder, Caroline C. Womack, Cora J. Young, and Trevor C. VandenBoer
Atmos. Meas. Tech., 13, 5873–5890, https://doi.org/10.5194/amt-13-5873-2020, https://doi.org/10.5194/amt-13-5873-2020, 2020
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Nitrous acid (HONO) is a key intermediate in the generation of oxidants and fate of nitrogen oxides in the atmosphere. High-purity calibration sources that produce stable atmospherically relevant levels under field conditions have not been made to date, reducing measurement accuracy. In this study a simple salt-coated tube humidified with water vapor is demonstrated to produce pure stable low levels of HONO, with modifications allowing the generation of higher amounts.
Joel Alroe, Luke T. Cravigan, Branka Miljevic, Graham R. Johnson, Paul Selleck, Ruhi S. Humphries, Melita D. Keywood, Scott D. Chambers, Alastair G. Williams, and Zoran D. Ristovski
Atmos. Chem. Phys., 20, 8047–8062, https://doi.org/10.5194/acp-20-8047-2020, https://doi.org/10.5194/acp-20-8047-2020, 2020
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We present findings from an austral summer voyage across the full latitudinal width of the Southern Ocean, south of Australia. Aerosol properties were strongly influenced by marine biological activity, synoptic-scale weather systems, and long-range transport of continental-influenced air masses. The meteorological history of the sampled air masses is shown to have a vital limiting influence on cloud condensation nuclei and the accuracy of modelled sea spray aerosol concentrations.
Luke T. Cravigan, Marc D. Mallet, Petri Vaattovaara, Mike J. Harvey, Cliff S. Law, Robin L. Modini, Lynn M. Russell, Ed Stelcer, David D. Cohen, Greg Olsen, Karl Safi, Timothy J. Burrell, and Zoran Ristovski
Atmos. Chem. Phys., 20, 7955–7977, https://doi.org/10.5194/acp-20-7955-2020, https://doi.org/10.5194/acp-20-7955-2020, 2020
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Aerosol–cloud interactions in remote marine environments are poorly represented in atmospheric modelling, particularly over the Southern Hemisphere. This work reports in situ chamber observations of sea spray aerosol composition and water uptake during the Surface Ocean Aerosol Production (SOAP) voyage. Observations were compared with currently applied models for sea spray organic enrichment. The sea spray hygroscopicity was persistently high, even at high organic fractions.
Louisa J. Kramer, Leigh R. Crilley, Thomas J. Adams, Stephen M. Ball, Francis D. Pope, and William J. Bloss
Atmos. Chem. Phys., 20, 5231–5248, https://doi.org/10.5194/acp-20-5231-2020, https://doi.org/10.5194/acp-20-5231-2020, 2020
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HONO is a large source of OH radicals, which can drive VOC oxidation, leading to the formation of ozone and secondary organic aerosols. Here we investigate primary vehicle emissions of HONO from measurements in a road tunnel in Birmingham, UK. A HONO/NOx emission ratio was detemined and compared to previous studies. Results indicate HONO/NOx has not varied much over the last two decades and technologies aimed at reducing NO2 may have also resulted in a reduction in direct HONO vehicle emissions.
Roberto Sommariva, Louisa J. Kramer, Leigh R. Crilley, Mohammed S. Alam, and William J. Bloss
Atmos. Meas. Tech., 13, 1655–1670, https://doi.org/10.5194/amt-13-1655-2020, https://doi.org/10.5194/amt-13-1655-2020, 2020
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Ozone is a key atmospheric pollutant formed through chemical processing of natural and anthropogenic emissions and removed by reaction with organic compounds emitted by plants. We describe a new instrument – the
Total Ozone Reactivity Systemor TORS – that measures the total loss of ozone in the troposphere. The objective of the TORS instrument is to provide an estimate of the organic compounds emitted by plants which are not measured and thus to improve our understanding of the ozone budget.
Leigh R. Crilley, Ajit Singh, Louisa J. Kramer, Marvin D. Shaw, Mohammed S. Alam, Joshua S. Apte, William J. Bloss, Lea Hildebrandt Ruiz, Pingqing Fu, Weiqi Fu, Shahzad Gani, Michael Gatari, Evgenia Ilyinskaya, Alastair C. Lewis, David Ng'ang'a, Yele Sun, Rachel C. W. Whitty, Siyao Yue, Stuart Young, and Francis D. Pope
Atmos. Meas. Tech., 13, 1181–1193, https://doi.org/10.5194/amt-13-1181-2020, https://doi.org/10.5194/amt-13-1181-2020, 2020
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There is considerable interest in using low-cost optical particle counters (OPCs) for particle mass measurements; however, there is no agreed upon method with respect to calibration. Here we exploit a number of datasets globally to demonstrate that particle composition and relative humidity are the key factors affecting measured concentrations from a low-cost OPC, and we present a simple correction methodology that corrects for this influence.
Leigh R. Crilley, Louisa J. Kramer, Bin Ouyang, Jun Duan, Wenqian Zhang, Shengrui Tong, Maofa Ge, Ke Tang, Min Qin, Pinhua Xie, Marvin D. Shaw, Alastair C. Lewis, Archit Mehra, Thomas J. Bannan, Stephen D. Worrall, Michael Priestley, Asan Bacak, Hugh Coe, James Allan, Carl J. Percival, Olalekan A. M. Popoola, Roderic L. Jones, and William J. Bloss
Atmos. Meas. Tech., 12, 6449–6463, https://doi.org/10.5194/amt-12-6449-2019, https://doi.org/10.5194/amt-12-6449-2019, 2019
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Nitrous acid (HONO) is key species for understanding tropospheric chemistry, yet accurate and precise measurements are challenging. Here we report an inter–comparison exercise of a number of instruments that measured HONO in a highly polluted location (Beijing). All instruments agreed on the temporal trends yet displayed divergence in absolute concentrations. The cause of this divergence was unclear, but it may in part be due to spatial variability in instrument location.
Melita Keywood, Paul Selleck, Fabienne Reisen, David Cohen, Scott Chambers, Min Cheng, Martin Cope, Suzanne Crumeyrolle, Erin Dunne, Kathryn Emmerson, Rosemary Fedele, Ian Galbally, Rob Gillett, Alan Griffiths, Elise-Andree Guerette, James Harnwell, Ruhi Humphries, Sarah Lawson, Branka Miljevic, Suzie Molloy, Jennifer Powell, Jack Simmons, Zoran Ristovski, and Jason Ward
Earth Syst. Sci. Data, 11, 1883–1903, https://doi.org/10.5194/essd-11-1883-2019, https://doi.org/10.5194/essd-11-1883-2019, 2019
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The Sydney Particle Study increased scientific knowledge of the processes leading to particle formation and transformations in Sydney through two comprehensive observation programs which are described in detail here. The data set and its analysis underpin comprehensive chemical transport modelling tools that can be used to assist in the development of a long-term control strategy for particles in Sydney and thus reduce the impact of particles on human health.
Rupert Holzinger, W. Joe F. Acton, William J. Bloss, Martin Breitenlechner, Leigh R. Crilley, Sébastien Dusanter, Marc Gonin, Valerie Gros, Frank N. Keutsch, Astrid Kiendler-Scharr, Louisa J. Kramer, Jordan E. Krechmer, Baptiste Languille, Nadine Locoge, Felipe Lopez-Hilfiker, Dušan Materić, Sergi Moreno, Eiko Nemitz, Lauriane L. J. Quéléver, Roland Sarda Esteve, Stéphane Sauvage, Simon Schallhart, Roberto Sommariva, Ralf Tillmann, Sergej Wedel, David R. Worton, Kangming Xu, and Alexander Zaytsev
Atmos. Meas. Tech., 12, 6193–6208, https://doi.org/10.5194/amt-12-6193-2019, https://doi.org/10.5194/amt-12-6193-2019, 2019
Zongbo Shi, Tuan Vu, Simone Kotthaus, Roy M. Harrison, Sue Grimmond, Siyao Yue, Tong Zhu, James Lee, Yiqun Han, Matthias Demuzere, Rachel E. Dunmore, Lujie Ren, Di Liu, Yuanlin Wang, Oliver Wild, James Allan, W. Joe Acton, Janet Barlow, Benjamin Barratt, David Beddows, William J. Bloss, Giulia Calzolai, David Carruthers, David C. Carslaw, Queenie Chan, Lia Chatzidiakou, Yang Chen, Leigh Crilley, Hugh Coe, Tie Dai, Ruth Doherty, Fengkui Duan, Pingqing Fu, Baozhu Ge, Maofa Ge, Daobo Guan, Jacqueline F. Hamilton, Kebin He, Mathew Heal, Dwayne Heard, C. Nicholas Hewitt, Michael Hollaway, Min Hu, Dongsheng Ji, Xujiang Jiang, Rod Jones, Markus Kalberer, Frank J. Kelly, Louisa Kramer, Ben Langford, Chun Lin, Alastair C. Lewis, Jie Li, Weijun Li, Huan Liu, Junfeng Liu, Miranda Loh, Keding Lu, Franco Lucarelli, Graham Mann, Gordon McFiggans, Mark R. Miller, Graham Mills, Paul Monk, Eiko Nemitz, Fionna O'Connor, Bin Ouyang, Paul I. Palmer, Carl Percival, Olalekan Popoola, Claire Reeves, Andrew R. Rickard, Longyi Shao, Guangyu Shi, Dominick Spracklen, David Stevenson, Yele Sun, Zhiwei Sun, Shu Tao, Shengrui Tong, Qingqing Wang, Wenhua Wang, Xinming Wang, Xuejun Wang, Zifang Wang, Lianfang Wei, Lisa Whalley, Xuefang Wu, Zhijun Wu, Pinhua Xie, Fumo Yang, Qiang Zhang, Yanli Zhang, Yuanhang Zhang, and Mei Zheng
Atmos. Chem. Phys., 19, 7519–7546, https://doi.org/10.5194/acp-19-7519-2019, https://doi.org/10.5194/acp-19-7519-2019, 2019
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APHH-Beijing is a collaborative international research programme to study the sources, processes and health effects of air pollution in Beijing. This introduction to the special issue provides an overview of (i) the APHH-Beijing programme, (ii) the measurement and modelling activities performed as part of it and (iii) the air quality and meteorological conditions during joint intensive field campaigns as a core activity within APHH-Beijing.
Reece A. Brown, Svetlana Stevanovic, Steven Bottle, and Zoran D. Ristovski
Atmos. Meas. Tech., 12, 2387–2401, https://doi.org/10.5194/amt-12-2387-2019, https://doi.org/10.5194/amt-12-2387-2019, 2019
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The paper details the design and characterization of a novel instrument for the measurement of particle reactivity and potential bioactivity, the PINQ. It continuously collects particles, regardless of size or composition, directly into a very small amount of liquid with a collection efficiency of > 0.97 and a cut-off size of 20 nm. PINQ has the highest time resolution, of only 1 min, and is very sensitive to various reactive species from the air.
Tommaso F. Villa, Reece A. Brown, E. Rohan Jayaratne, L. Felipe Gonzalez, Lidia Morawska, and Zoran D. Ristovski
Atmos. Meas. Tech., 12, 691–702, https://doi.org/10.5194/amt-12-691-2019, https://doi.org/10.5194/amt-12-691-2019, 2019
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This research demonstrates the use of an unmanned aerial vehicle (UAV) to characterize the gaseous and diesel particle emissions of a ship at sea. The field study was part of the research voyage “The Great Barrier Reef as a significant source of climatically relevant aerosol particles” on board the RV Investigator around the Australian Great Barrier Reef. Measurements of the RV Investigator exhaust plume were carried out while the ship was operating at sea, at a steady engine load.
Robbie Ramsay, Chiara F. Di Marco, Mathew R. Heal, Marsailidh M. Twigg, Nicholas Cowan, Matthew R. Jones, Sarah R. Leeson, William J. Bloss, Louisa J. Kramer, Leigh Crilley, Matthias Sörgel, Meinrat Andreae, and Eiko Nemitz
Atmos. Chem. Phys., 18, 16953–16978, https://doi.org/10.5194/acp-18-16953-2018, https://doi.org/10.5194/acp-18-16953-2018, 2018
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Understanding the impact of agricultural activities on the atmosphere requires more measurements of inorganic trace gases and associated aerosol counterparts. This research presents 1 month of measurements above agricultural grassland during a period of fertiliser application. It was found that emissions of the important trace gases ammonia and nitrous acid peaked after fertiliser use and that the velocity at which the measured aerosols were deposited was dependent upon their size.
Daocheng Gong, Hao Wang, Shenyang Zhang, Yu Wang, Shaw Chen Liu, Hai Guo, Min Shao, Congrong He, Duohong Chen, Lingyan He, Lei Zhou, Lidia Morawska, Yuanhang Zhang, and Boguang Wang
Atmos. Chem. Phys., 18, 14417–14432, https://doi.org/10.5194/acp-18-14417-2018, https://doi.org/10.5194/acp-18-14417-2018, 2018
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The complex air pollution in the air-polluted Pearl River Delta (PRD) region in southern China has significantly elevated the background atmospheric oxidative capacity of the adjacent forests and subsequently lowered the levels of important biogenic volatile organic compounds, such as isoprene, which probably affect the regional air quality and ecological environment in the long term.
Rohan Jayaratne, Xiaoting Liu, Phong Thai, Matthew Dunbabin, and Lidia Morawska
Atmos. Meas. Tech., 11, 4883–4890, https://doi.org/10.5194/amt-11-4883-2018, https://doi.org/10.5194/amt-11-4883-2018, 2018
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It is important to correctly interpret the readings reported by low cost airborne particle sensors at high humidity. We demonstrate that deliquescent growth of particles and the formation of fog droplets in the atmosphere can lead to significant increases in particle number and mass concentrations reported by such sensors, unless they are fitted with dryers at the inlet. This is important as air quality standards for particles are specifically limited to solid particles.
Buddhi Pushpawela, Rohan Jayaratne, and Lidia Morawska
Atmos. Chem. Phys., 18, 11171–11183, https://doi.org/10.5194/acp-18-11171-2018, https://doi.org/10.5194/acp-18-11171-2018, 2018
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New particle formation (NPF) is a common occurrence in urban environments. Using a 500-day dataset obtained in Brisbane, Australia, we observed that NPF events occurred on 37 % of days and 10 % of nights. However, particle growth occurred on 70 % of nights. We show that when particles are measured by an instrument with a detection limit of 3 nm or above, particle growth events may be easily misidentified as NPF events. This can lead to an overestimation of the occurrence of NPF events.
Prasad Kasibhatla, Tomás Sherwen, Mathew J. Evans, Lucy J. Carpenter, Chris Reed, Becky Alexander, Qianjie Chen, Melissa P. Sulprizio, James D. Lee, Katie A. Read, William Bloss, Leigh R. Crilley, William C. Keene, Alexander A. P. Pszenny, and Alma Hodzic
Atmos. Chem. Phys., 18, 11185–11203, https://doi.org/10.5194/acp-18-11185-2018, https://doi.org/10.5194/acp-18-11185-2018, 2018
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Recent measurements of NOx and HONO suggest that photolysis of particulate nitrate in sea-salt aerosols is important in terms of marine boundary layer oxidant chemistry. We present the first global-scale assessment of the significance of this new chemical pathway for NOx, O3, and OH in the marine boundary layer. We also present a preliminary assessment of the potential impact of photolysis of particulate nitrate associated with other aerosol types on continental boundary layer chemistry.
Joel Alroe, Luke T. Cravigan, Marc D. Mallet, Zoran D. Ristovski, Branka Miljevic, Chiemeriwo G. Osuagwu, and Graham R. Johnson
Atmos. Meas. Tech., 11, 4361–4372, https://doi.org/10.5194/amt-11-4361-2018, https://doi.org/10.5194/amt-11-4361-2018, 2018
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This study describes a new volatility-based method to directly examine the composition and corresponding hygroscopic contribution of mixed aerosol components. Measurements of chamber-generated secondary organic aerosol and coastal marine aerosol demonstrated effective separation of both internal and external mixtures. In each case, the findings enabled composition-based models to reliably reproduce observed particle hygroscopicities.
Leigh R. Crilley, Marvin Shaw, Ryan Pound, Louisa J. Kramer, Robin Price, Stuart Young, Alastair C. Lewis, and Francis D. Pope
Atmos. Meas. Tech., 11, 709–720, https://doi.org/10.5194/amt-11-709-2018, https://doi.org/10.5194/amt-11-709-2018, 2018
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The affordability and small size of low-cost particle sensors make them attractive for air pollution experiments that require multiple instruments, or take place in hard-to-access locations or low-income countries. For any sensor to be useful, its accuracy and precision need to be known. We evaluate the Alphasense OPC-N2 for monitoring airborne particles at typical UK urban background sites. The devices were found to be accurate provided they are correctly calibrated.
Marc D. Mallet, Maximilien J. Desservettaz, Branka Miljevic, Andelija Milic, Zoran D. Ristovski, Joel Alroe, Luke T. Cravigan, E. Rohan Jayaratne, Clare Paton-Walsh, David W. T. Griffith, Stephen R. Wilson, Graham Kettlewell, Marcel V. van der Schoot, Paul Selleck, Fabienne Reisen, Sarah J. Lawson, Jason Ward, James Harnwell, Min Cheng, Rob W. Gillett, Suzie B. Molloy, Dean Howard, Peter F. Nelson, Anthony L. Morrison, Grant C. Edwards, Alastair G. Williams, Scott D. Chambers, Sylvester Werczynski, Leah R. Williams, V. Holly L. Winton, Brad Atkinson, Xianyu Wang, and Melita D. Keywood
Atmos. Chem. Phys., 17, 13681–13697, https://doi.org/10.5194/acp-17-13681-2017, https://doi.org/10.5194/acp-17-13681-2017, 2017
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Fires play an important role within atmosphere. Gaseous and aerosol emissions influence Earth's temperature but these emissions can vary drastically across region and season. The SAFIRED (Savannah Fires in the Early Dry Season) campaign was undertaken at the Australian Tropical Research Station in north Australia during the 2014 early dry season. This paper presents an overview of the fires in this region, the measurements of their emissions and the implications of these fires on the atmosphere.
Cliff S. Law, Murray J. Smith, Mike J. Harvey, Thomas G. Bell, Luke T. Cravigan, Fiona C. Elliott, Sarah J. Lawson, Martine Lizotte, Andrew Marriner, John McGregor, Zoran Ristovski, Karl A. Safi, Eric S. Saltzman, Petri Vaattovaara, and Carolyn F. Walker
Atmos. Chem. Phys., 17, 13645–13667, https://doi.org/10.5194/acp-17-13645-2017, https://doi.org/10.5194/acp-17-13645-2017, 2017
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We carried out a multidisciplinary study to examine how aerosol production is influenced by the production and emission of trace gases and particles in the surface ocean. Phytoplankton blooms of different species composition in frontal waters southeast of New Zealand were a significant source of dimethylsulfide and other aerosol precursors. The relationships between surface ocean biogeochemistry and aerosol composition will inform the understanding of aerosol production over the remote ocean.
Sarah J. Lawson, Martin Cope, Sunhee Lee, Ian E. Galbally, Zoran Ristovski, and Melita D. Keywood
Atmos. Chem. Phys., 17, 11707–11726, https://doi.org/10.5194/acp-17-11707-2017, https://doi.org/10.5194/acp-17-11707-2017, 2017
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A high-resolution chemical transport model was used to reproduce observed smoke plumes. The model output was highly sensitive to fire emission factors and meteorology, particularly for secondary pollutant ozone. Aged urban air (age = 2 days) was the major source of ozone observed, with minor contributions from the fire. This work highlights the importance of assessing model sensitivity and the use of modelling to determine the contribution from different sources to atmospheric composition.
Rohan Jayaratne, Buddhi Pushpawela, Congrong He, Hui Li, Jian Gao, Fahe Chai, and Lidia Morawska
Atmos. Chem. Phys., 17, 8825–8835, https://doi.org/10.5194/acp-17-8825-2017, https://doi.org/10.5194/acp-17-8825-2017, 2017
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Observations over a continuous 3-month period in Beijing showed 26 new particle formation (NPF) events, generally coinciding with periods with relatively clean air when the wind direction was from the less industrialized north. Large particles in the atmosphere suppress the gaseous supersaturation that is required for NPF. No events were observed when the daily mean PM2.5 concentration exceeded 43 µg m−3. These results provide useful insight into the formation of haze events in megacities.
Chris Reed, Mathew J. Evans, Leigh R. Crilley, William J. Bloss, Tomás Sherwen, Katie A. Read, James D. Lee, and Lucy J. Carpenter
Atmos. Chem. Phys., 17, 4081–4092, https://doi.org/10.5194/acp-17-4081-2017, https://doi.org/10.5194/acp-17-4081-2017, 2017
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The source of ozone-depleting compounds in the remote troposphere has been thought to be long-range transport of secondary pollutants such as organic nitrates. Processing of organic nitrates to nitric acid and subsequent deposition on surfaces in the atmosphere was thought to remove these nitrates from the ozone–NOx–HOx cycle. We found through observation of NOx in the remote tropical troposphere at the Cape Verde Observatory that surface nitrates can be released back into the atmosphere.
Andelija Milic, Marc D. Mallet, Luke T. Cravigan, Joel Alroe, Zoran D. Ristovski, Paul Selleck, Sarah J. Lawson, Jason Ward, Maximilien J. Desservettaz, Clare Paton-Walsh, Leah R. Williams, Melita D. Keywood, and Branka Miljevic
Atmos. Chem. Phys., 17, 3945–3961, https://doi.org/10.5194/acp-17-3945-2017, https://doi.org/10.5194/acp-17-3945-2017, 2017
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This study reports chemical characterization of fresh and processed aerosols sampled over a month-long field campaign, during the intense fire period in Australian tropical savannah region. The study illustrates diversity in fire emissions and importance of processed fire emissions and formation of secondary species, including biogenic secondary species, in northern Australia.
Marc D. Mallet, Luke T. Cravigan, Andelija Milic, Joel Alroe, Zoran D. Ristovski, Jason Ward, Melita Keywood, Leah R. Williams, Paul Selleck, and Branka Miljevic
Atmos. Chem. Phys., 17, 3605–3617, https://doi.org/10.5194/acp-17-3605-2017, https://doi.org/10.5194/acp-17-3605-2017, 2017
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This paper presents data on the size, composition and concentration of aerosol particles emitted from north Australian savannah fires and how these properties influence cloud condensation nuclei (CCN) concentrations. Both the size and composition of aerosol were found to be important in determining CCN. Despite large CCNc enhancements during periods of close biomass burning, the aerosol was very weakly hygroscopic which should be accounted for in climate models to avoid large CCNc overestimates.
Farhad Salimi, Md. Mahmudur Rahman, Sam Clifford, Zoran Ristovski, and Lidia Morawska
Atmos. Chem. Phys., 17, 521–530, https://doi.org/10.5194/acp-17-521-2017, https://doi.org/10.5194/acp-17-521-2017, 2017
Chris Reed, Charlotte A. Brumby, Leigh R. Crilley, Louisa J. Kramer, William J. Bloss, Paul W. Seakins, James D. Lee, and Lucy J. Carpenter
Atmos. Meas. Tech., 9, 2483–2495, https://doi.org/10.5194/amt-9-2483-2016, https://doi.org/10.5194/amt-9-2483-2016, 2016
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A new method of measuring nitrous acid (HONO), a potent mediator of air quality in the atmosphere as well as an important indoor pollutant, is presented. The new method relies on simple, proven techniques already widely applied to other atmospheric compounds. The technique can be retrofitted to existing analysers at minimal cost, or developed into instruments capable of very fast measurement which allow for more complex analysis of the behaviour of HONO.
F. Salimi, L. R. Crilley, S. Stevanovic, Z. Ristovski, M. Mazaheri, C. He, G. Johnson, G. Ayoko, and L. Morawska
Atmos. Chem. Phys., 15, 13475–13485, https://doi.org/10.5194/acp-15-13475-2015, https://doi.org/10.5194/acp-15-13475-2015, 2015
S. J. Lawson, M. D. Keywood, I. E. Galbally, J. L. Gras, J. M. Cainey, M. E. Cope, P. B. Krummel, P. J. Fraser, L. P. Steele, S. T. Bentley, C. P. Meyer, Z. Ristovski, and A. H. Goldstein
Atmos. Chem. Phys., 15, 13393–13411, https://doi.org/10.5194/acp-15-13393-2015, https://doi.org/10.5194/acp-15-13393-2015, 2015
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Biomass burning (BB) plumes were opportunistically measured at the Cape Grim Baseline Station in Tasmania, Australia. We provide a unique set of trace gas and particle emission factors for temperate Australian coastal heathland fires, and attribute a major short-lived enhancement in emission ratios to a minor rainfall event. The ability of BB particles to act as cloud condensation nuclei, and the contribution of BB emissions to observed particle growth and ozone enhancements are discussed.
A. M. Pourkhesalian, S. Stevanovic, M. M. Rahman, E. M. Faghihi, S. E. Bottle, A. R. Masri, R. J. Brown, and Z. D. Ristovski
Atmos. Chem. Phys., 15, 9099–9108, https://doi.org/10.5194/acp-15-9099-2015, https://doi.org/10.5194/acp-15-9099-2015, 2015
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This study investigates the effects of biodiesel's chemical composition on the volatility and reactive oxygenate species of fresh and aged diesel particulate matter.
Using a potential aerosol mass chamber, changes of volatility and reactive oxygenated species are studied. The study concludes that more saturated and more oxygenated diesel fuels can cause more volatile particles carrying more reactive oxygenated species whether before or after aging.
M. Brines, M. Dall'Osto, D. C. S. Beddows, R. M. Harrison, F. Gómez-Moreno, L. Núñez, B. Artíñano, F. Costabile, G. P. Gobbi, F. Salimi, L. Morawska, C. Sioutas, and X. Querol
Atmos. Chem. Phys., 15, 5929–5945, https://doi.org/10.5194/acp-15-5929-2015, https://doi.org/10.5194/acp-15-5929-2015, 2015
L. R. Crilley, W. J. Bloss, J. Yin, D. C. S. Beddows, R. M. Harrison, J. D. Allan, D. E. Young, M. Flynn, P. Williams, P. Zotter, A. S. H. Prevot, M. R. Heal, J. F. Barlow, C. H. Halios, J. D. Lee, S. Szidat, and C. Mohr
Atmos. Chem. Phys., 15, 3149–3171, https://doi.org/10.5194/acp-15-3149-2015, https://doi.org/10.5194/acp-15-3149-2015, 2015
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Wood is a renewable fuel but its combustion for residential heating releases a number of locally acting air pollutants, most notably particulate matter known to have adverse effects on human health. This paper used chemical tracers for wood smoke to estimate the contribution that burning wood makes to concentrations of airborne particles in the atmosphere of southern England and most particularly in London.
S. J. Lawson, P. W. Selleck, I. E. Galbally, M. D. Keywood, M. J. Harvey, C. Lerot, D. Helmig, and Z. Ristovski
Atmos. Chem. Phys., 15, 223–240, https://doi.org/10.5194/acp-15-223-2015, https://doi.org/10.5194/acp-15-223-2015, 2015
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Glyoxal and methylglyoxal are short-lived organic trace gases and important precursors of secondary organic aerosol. Measurements over oceans are sparse. We present the first in situ glyoxal and methylglyoxal observations over remote temperate oceans, alongside observations of precursor gases. Precursor gases cannot explain observed mixing ratios, highlighting an unknown source. We show a large discrepancy between calculated vertical column densities of glyoxal and those retrieved by satellite.
M. Tjernström, C. Leck, C. E. Birch, J. W. Bottenheim, B. J. Brooks, I. M. Brooks, L. Bäcklin, R. Y.-W. Chang, G. de Leeuw, L. Di Liberto, S. de la Rosa, E. Granath, M. Graus, A. Hansel, J. Heintzenberg, A. Held, A. Hind, P. Johnston, J. Knulst, M. Martin, P. A. Matrai, T. Mauritsen, M. Müller, S. J. Norris, M. V. Orellana, D. A. Orsini, J. Paatero, P. O. G. Persson, Q. Gao, C. Rauschenberg, Z. Ristovski, J. Sedlar, M. D. Shupe, B. Sierau, A. Sirevaag, S. Sjogren, O. Stetzer, E. Swietlicki, M. Szczodrak, P. Vaattovaara, N. Wahlberg, M. Westberg, and C. R. Wheeler
Atmos. Chem. Phys., 14, 2823–2869, https://doi.org/10.5194/acp-14-2823-2014, https://doi.org/10.5194/acp-14-2823-2014, 2014
Related subject area
Subject: Aerosols | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Quantification and characterization of primary biological aerosol particles and microbes aerosolized from Baltic seawater
Brownness of organics in anthropogenic biomass burning aerosols over South Asia
Source apportionment of particle number size distribution at the street canyon and urban background sites
Long-range transport of coarse mineral dust: an evaluation of the Met Office Unified Model against aircraft observations
Extreme Saharan dust events expand northward over the Atlantic and Europe, prompting record-breaking PM10 and PM2.5 episodes
Atmospheric black carbon in the metropolitan area of La Paz and El Alto, Bolivia: concentration levels and emission sources
Changing optical properties of black carbon and brown carbon aerosols during long-range transport from the Indo-Gangetic Plain to the equatorial Indian Ocean
Aerosol size distribution properties associated with cold-air outbreaks in the Norwegian Arctic
Ice-nucleating particles active below −24 °C in a Finnish boreal forest and their relationship to bioaerosols
Measurements of particle emissions of an A350-941 burning 100 % sustainable aviation fuels in cruise
Vertical distribution of ice nucleating particles over the boreal forest of Hyytiälä, Finland
Multi-year gradient measurements of sea spray fluxes over the Baltic Sea and the North Atlantic Ocean
External particle mixing influences hygroscopicity in a sub-urban area
Measurement report: In situ vertical profiles of below-cloud aerosol over the central Greenland Ice Sheet
Occurrence, abundance, and formation of atmospheric tarballs from a wide range of wildfires in the western US
Measurement report: Contribution of atmospheric new particle formation to ultrafine particle concentration, cloud condensation nuclei, and radiative forcing – results from 5-year observations in central Europe
Simulated contrail-processed aviation soot aerosols are poor ice-nucleating particles at cirrus temperatures
Biological and dust aerosols as sources of ice-nucleating particles in the eastern Mediterranean: source apportionment, atmospheric processing and parameterization
Quantifying the dust direct radiative effect in the southwestern United States: findings from multiyear measurements
How horizontal transport and turbulent mixing impact aerosol particle and precursor concentrations at a background site in the UAE
Markedly different impacts of primary emissions and secondary aerosol formation on aerosol mixing states revealed by simultaneous measurements of CCNC, H(/V)TDMA, and SP2
Vertically resolved aerosol variability at the Amazon Tall Tower Observatory under wet-season conditions
Measurement report: Analysis of aerosol optical depth variation at Zhongshan Station in Antarctica
Vertical structure of a springtime smoky and humid troposphere over the southeast Atlantic from aircraft and reanalysis
Shipborne observations of black carbon aerosols in the western Arctic Ocean during summer and autumn 2016–2020: impact of boreal fires
High ice-nucleating particle concentrations associated with Arctic haze in springtime cold-air outbreaks
CCN estimations at a high-altitude remote site: role of organic aerosol variability and hygroscopicity
Attribution of aerosol particle number size distributions to main sources using an 11-year urban dataset
Large Spatiotemporal Variability in Aerosol Properties over Central Argentina during the CACTI Field Campaign
Contribution of fluorescent primary biological aerosol particles to low-level Arctic cloud residuals
Opinion: New directions in atmospheric research offered by research infrastructures combined with open and data-intensive science
Measurement report: A comparison of ground-level ice-nucleating-particle abundance and aerosol properties during autumn at contrasting marine and terrestrial locations
Efficient droplet activation of ambient black carbon particles in a suburban environment
Tropospheric sulfate from Cumbre Vieja (La Palma) observed over Cabo Verde contrasted with background conditions: a lidar case study of aerosol extinction, backscatter, depolarization and lidar ratio profiles at 355, 532 and 1064 nm
The radiative impact of biomass burning aerosols on dust emissions over Namibia and the long-range transport of smoke observed during the Aerosols, Radiation and Clouds in southern Africa (AEROCLO-sA) campaign
Extending the wind profile beyond the surface layer by combining physical and machine learning approaches
Amazonian aerosol size distributions in a lognormal phase space: characteristics and trajectories
Measurement report: Hygroscopicity of size-selected aerosol particles in the heavily polluted urban atmosphere of Delhi: impacts of chloride aerosol
An observation-constrained estimation of brown carbon aerosol direct radiative effects
The Puy de Dôme ICe Nucleation Intercomparison Campaign (PICNIC): comparison between online and offline methods in ambient air
Optical properties and simple forcing efficiency of the organic aerosols and black carbon emitted by residential wood burning in rural central Europe
Particle phase state and aerosol liquid water greatly impact secondary aerosol formation: insights into phase transition and its role in haze events
Measurement Report: Comparative Analysis of Fluorescing African Dust Particles in Spain and Puerto Rico
Measurement report: Nocturnal subsidence behind the cold front enhances surface particulate matter in plains regions: observations from the mobile multi-lidar system
Increase in precipitation scavenging contributes to long-term reductions of light-absorbing aerosol in the Arctic
Sea spray emissions from the Baltic Sea: comparison of aerosol eddy covariance fluxes and chamber-simulated sea spray emissions
Higher absorption enhancement of black carbon in summer shown by 2-year measurements at the high-altitude mountain site of Pic du Midi Observatory in the French Pyrenees
Variations of the atmospheric polycyclic aromatic hydrocarbon concentrations, sources, and health risk and the direct medical costs of lung cancer around the Bohai Sea against a background of pollution prevention and control in China
The Spatial and Temporal Impact of the February 26, 2023, Dust Storm on the Meteorological Conditions and Particulate Matter Concentrations Across New Mexico and West Texas
Characterization of aerosol over the Eastern Mediterranean by polarization sensitive Raman lidar measurements during A-LIFE – aerosol type classification and type separation
Julika Zinke, Gabriel Pereira Freitas, Rachel Ann Foster, Paul Zieger, Ernst Douglas Nilsson, Piotr Markuszewski, and Matthew Edward Salter
Atmos. Chem. Phys., 24, 13413–13428, https://doi.org/10.5194/acp-24-13413-2024, https://doi.org/10.5194/acp-24-13413-2024, 2024
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Bioaerosols, which can influence climate and human health, were studied in the Baltic Sea. In May and August 2021, we used a sea spray simulation chamber during two ship-based campaigns to collect and measure these aerosols. We found that microbes were enriched in air compared to seawater. Bacterial diversity was analysed using DNA sequencing. Our methods provided consistent estimates of microbial emission fluxes, aligning with previous studies.
Chimurkar Navinya, Taveen Singh Kapoor, Gupta Anurag, Chandra Venkataraman, Harish C. Phuleria, and Rajan K. Chakrabarty
Atmos. Chem. Phys., 24, 13285–13297, https://doi.org/10.5194/acp-24-13285-2024, https://doi.org/10.5194/acp-24-13285-2024, 2024
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Brown carbon (BrC) aerosols show an order-of-magnitude variation in their light absorption strength. Our understanding of BrC from real-world biomass burning remains limited, complicating the determination of its radiative impact. Our study reports absorption properties of BrC emitted from four major biomass burning sources using field measurements in India. It develops an absorption parameterization for BrC and examines the spatial variability in BrC's absorption strength across India.
Sami D. Harni, Minna Aurela, Sanna Saarikoski, Jarkko V. Niemi, Harri Portin, Hanna Manninen, Ville Leinonen, Pasi Aalto, Phil K. Hopke, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 24, 12143–12160, https://doi.org/10.5194/acp-24-12143-2024, https://doi.org/10.5194/acp-24-12143-2024, 2024
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In this study, particle number size distribution data were used in a novel way in positive matrix factorization analysis to find aerosol source profiles in the area. Measurements were made in Helsinki at a street canyon and urban background sites between February 2015 and June 2019. Five different aerosol sources were identified. These sources underline the significance of traffic-related emissions in urban environments despite recent improvements in emission reduction technologies.
Natalie G. Ratcliffe, Claire L. Ryder, Nicolas Bellouin, Stephanie Woodward, Anthony Jones, Ben Johnson, Lisa-Maria Wieland, Maximilian Dollner, Josef Gasteiger, and Bernadett Weinzierl
Atmos. Chem. Phys., 24, 12161–12181, https://doi.org/10.5194/acp-24-12161-2024, https://doi.org/10.5194/acp-24-12161-2024, 2024
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Large mineral dust particles are more abundant in the atmosphere than expected and have different impacts on the environment than small particles, which are better represented in climate models. We use aircraft measurements to assess a climate model representation of large-dust transport. We find that the model underestimates the amount of large dust at all stages of transport and that fast removal of the large particles increases this underestimation with distance from the Sahara.
Sergio Rodríguez and Jessica López-Darias
Atmos. Chem. Phys., 24, 12031–12053, https://doi.org/10.5194/acp-24-12031-2024, https://doi.org/10.5194/acp-24-12031-2024, 2024
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Extreme Saharan dust events expanded northward to the Atlantic and Europe, prompting record-breaking PM10 and PM2.5 events. These episodes are caused by low-to-high dipole meteorology during hemispheric anomalies characterized by subtropical anticyclones shifting to higher latitudes, anomalous low pressures beyond the tropics and amplified Rossby waves. Extreme dust events occur in a paradoxical context of a multidecadal decrease in dust emissions, a topic that requires further investigation.
Valeria Mardoñez-Balderrama, Griša Močnik, Marco Pandolfi, Robin L. Modini, Fernando Velarde, Laura Renzi, Angela Marinoni, Jean-Luc Jaffrezo, Isabel Moreno R., Diego Aliaga, Federico Bianchi, Claudia Mohr, Martin Gysel-Beer, Patrick Ginot, Radovan Krejci, Alfred Wiedensohler, Gaëlle Uzu, Marcos Andrade, and Paolo Laj
Atmos. Chem. Phys., 24, 12055–12077, https://doi.org/10.5194/acp-24-12055-2024, https://doi.org/10.5194/acp-24-12055-2024, 2024
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Levels of black carbon (BC) are scarcely reported in the Southern Hemisphere, especially in high-altitude conditions. This study provides insight into the concentration level, variability, and optical properties of BC in La Paz and El Alto and at the Chacaltaya Global Atmosphere Watch Station. Two methods of source apportionment of absorption were tested and compared showing traffic as the main contributor to absorption in the urban area, in addition to biomass and open waste burning.
Krishnakant Budhavant, Mohanan Remani Manoj, Hari Ram Chandrika Rajendran Nair, Samuel Mwaniki Gaita, Henry Holmstrand, Abdus Salam, Ahmed Muslim, Sreedharan Krishnakumari Satheesh, and Örjan Gustafsson
Atmos. Chem. Phys., 24, 11911–11925, https://doi.org/10.5194/acp-24-11911-2024, https://doi.org/10.5194/acp-24-11911-2024, 2024
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The South Asian Pollution Experiment 2018 used access to three strategically located receptor observatories. Observational constraints revealed opposing trends in the mass absorption cross sections of black carbon (BC MAC) and brown carbon (BrC MAC) during long-range transport. Models estimating the climate effects of BC aerosols may have underestimated the ambient BC MAC over distant receptor areas, leading to discrepancies in aerosol absorption predicted by observation-constrained models.
Abigail S. Williams, Jeramy L. Dedrick, Lynn M. Russell, Florian Tornow, Israel Silber, Ann M. Fridlind, Benjamin Swanson, Paul J. DeMott, Paul Zieger, and Radovan Krejci
Atmos. Chem. Phys., 24, 11791–11805, https://doi.org/10.5194/acp-24-11791-2024, https://doi.org/10.5194/acp-24-11791-2024, 2024
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The measured aerosol size distribution modes reveal distinct properties characteristic of cold-air outbreaks in the Norwegian Arctic. We find higher sea spray number concentrations, smaller Hoppel minima, lower effective supersaturations, and accumulation-mode particle scavenging during cold-air outbreaks. These results advance our understanding of cold-air outbreak aerosol–cloud interactions in order to improve their accurate representation in models.
Franziska Vogel, Michael P. Adams, Larissa Lacher, Polly B. Foster, Grace C. E. Porter, Barbara Bertozzi, Kristina Höhler, Julia Schneider, Tobias Schorr, Nsikanabasi S. Umo, Jens Nadolny, Zoé Brasseur, Paavo Heikkilä, Erik S. Thomson, Nicole Büttner, Martin I. Daily, Romy Fösig, Alexander D. Harrison, Jorma Keskinen, Ulrike Proske, Jonathan Duplissy, Markku Kulmala, Tuukka Petäjä, Ottmar Möhler, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 11737–11757, https://doi.org/10.5194/acp-24-11737-2024, https://doi.org/10.5194/acp-24-11737-2024, 2024
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Primary ice formation in clouds strongly influences their properties; hence, it is important to understand the sources of ice-nucleating particles (INPs) and their variability. We present 2 months of INP measurements in a Finnish boreal forest using a new semi-autonomous INP counting device based on gas expansion. These results show strong variability in INP concentrations, and we present a case that the INPs we observe are, at least some of the time, of biological origin.
Rebecca Dischl, Daniel Sauer, Christiane Voigt, Theresa Harlaß, Felicitas Sakellariou, Raphael Märkl, Ulrich Schumann, Monika Scheibe, Stefan Kaufmann, Anke Roiger, Andreas Dörnbrack, Charles Renard, Maxime Gauthier, Peter Swann, Paul Madden, Darren Luff, Mark Johnson, Denise Ahrens, Reetu Sallinen, Tobias Schripp, Georg Eckel, Uwe Bauder, and Patrick Le Clercq
Atmos. Chem. Phys., 24, 11255–11273, https://doi.org/10.5194/acp-24-11255-2024, https://doi.org/10.5194/acp-24-11255-2024, 2024
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In-flight measurements of aircraft emissions burning 100 % sustainable aviation fuel (SAF) show reduced particle number concentrations up to 41 % compared to conventional jet fuel. Particle emissions are dependent on engine power setting, flight altitude, and fuel composition. Engine models show a good correlation with measurement results. Future increased prevalence of SAF can positively influence the climate impact of aviation.
Zoé Brasseur, Julia Schneider, Janne Lampilahti, Ville Vakkari, Victoria A. Sinclair, Christina J. Williamson, Carlton Xavier, Dmitri Moisseev, Markus Hartmann, Pyry Poutanen, Markus Lampimäki, Markku Kulmala, Tuukka Petäjä, Katrianne Lehtipalo, Erik S. Thomson, Kristina Höhler, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 24, 11305–11332, https://doi.org/10.5194/acp-24-11305-2024, https://doi.org/10.5194/acp-24-11305-2024, 2024
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Ice-nucleating particles (INPs) strongly influence the formation of clouds by initiating the formation of ice crystals. However, very little is known about the vertical distribution of INPs in the atmosphere. Here, we present aircraft measurements of INP concentrations above the Finnish boreal forest. Results show that near-surface INPs are efficiently transported and mixed within the boundary layer and occasionally reach the free troposphere.
Piotr Markuszewski, E. Douglas Nilsson, Julika Zinke, E. Monica Mårtensson, Matthew Salter, Przemysław Makuch, Małgorzata Kitowska, Iwona Niedźwiecka-Wróbel, Violetta Drozdowska, Dominik Lis, Tomasz Petelski, Luca Ferrero, and Jacek Piskozub
Atmos. Chem. Phys., 24, 11227–11253, https://doi.org/10.5194/acp-24-11227-2024, https://doi.org/10.5194/acp-24-11227-2024, 2024
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Our research provides new insights into the study of sea spray aerosol (SSA) emissions in the Baltic Sea and North Atlantic. We observed that SSA flux is suppressed during increased marine biological activity in the Baltic Sea. At the same time, the influence of wave age showed higher SSA emissions in the Baltic Sea for younger waves compared to the Atlantic Ocean. These insights underscore the complex interplay between biological activity and physical dynamics in regulating SSA emissions.
Shravan Deshmukh, Laurent Poulain, Birgit Wehner, Silvia Henning, Jean-Eudes Petit, Pauline Fombelle, Olivier Favez, Hartmut Herrmann, and Mira Pöhlker
EGUsphere, https://doi.org/10.5194/egusphere-2024-3027, https://doi.org/10.5194/egusphere-2024-3027, 2024
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Aerosol hygroscopicity has been investigated at the sub-urban site in Paris; analysis shows the sub-saturated regime's measured hygroscopicity and the chemically derived hygroscopic growth, shedding light on the large effect of external particle mixing and its influence on predicting hygroscopicity.
Heather Guy, Andrew S. Martin, Erik Olson, Ian M. Brooks, and Ryan R. Neely III
Atmos. Chem. Phys., 24, 11103–11114, https://doi.org/10.5194/acp-24-11103-2024, https://doi.org/10.5194/acp-24-11103-2024, 2024
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Aerosol particles impact cloud properties which influence Greenland Ice Sheet melt. Understanding the aerosol population that interacts with clouds is important for constraining future melt. Measurements of aerosols at cloud height over Greenland are rare, and surface measurements are often used to investigate cloud–aerosol interactions. We use a tethered balloon to measure aerosols up to cloud base and show that surface measurements are often not equivalent to those just below the cloud.
Kouji Adachi, Jack E. Dibb, Joseph M. Katich, Joshua P. Schwarz, Hongyu Guo, Pedro Campuzano-Jost, Jose L. Jimenez, Jeff Peischl, Christopher D. Holmes, and James Crawford
Atmos. Chem. Phys., 24, 10985–11004, https://doi.org/10.5194/acp-24-10985-2024, https://doi.org/10.5194/acp-24-10985-2024, 2024
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We examined aerosol particles from wildfires and identified tarballs (TBs) from the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) campaign. This study reveals the compositions, abundance, sizes, and mixing states of TBs and shows that TBs formed as the smoke aged for up to 5 h. This study provides measurements of TBs from various biomass-burning events and ages, enhancing our knowledge of TB emissions and our understanding of their climate impact.
Jia Sun, Markus Hermann, Kay Weinhold, Maik Merkel, Wolfram Birmili, Yifan Yang, Thomas Tuch, Harald Flentje, Björn Briel, Ludwig Ries, Cedric Couret, Michael Elsasser, Ralf Sohmer, Klaus Wirtz, Frank Meinhardt, Maik Schütze, Olaf Bath, Bryan Hellack, Veli-Matti Kerminen, Markku Kulmala, Nan Ma, and Alfred Wiedensohler
Atmos. Chem. Phys., 24, 10667–10687, https://doi.org/10.5194/acp-24-10667-2024, https://doi.org/10.5194/acp-24-10667-2024, 2024
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We investigated the characteristics of new particle formation (NPF) for various environments from urban background to high Alpine and the impacts of NPF on cloud condensation nuclei and aerosol radiative forcing. NPF features differ between site categories, implying the crucial role of local environmental factors such as the degree of emissions and meteorological conditions. The results also underscore the importance of local environments when assessing the impact of NPF on climate in models.
Baptiste Testa, Lukas Durdina, Jacinta Edebeli, Curdin Spirig, and Zamin A. Kanji
Atmos. Chem. Phys., 24, 10409–10424, https://doi.org/10.5194/acp-24-10409-2024, https://doi.org/10.5194/acp-24-10409-2024, 2024
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Aviation soot residuals released from contrails can become compacted upon sublimation of the ice crystals, generating new voids in the aggregates where ice nucleation can occur. Here we show that contrail-processed soot is highly compact but that it remains unable to form ice at a relative humidity different from that required for the formation of background cirrus from the more ubiquitous aqueous solution droplets, suggesting that it will not perturb cirrus cloud formation via ice nucleation.
Kunfeng Gao, Franziska Vogel, Romanos Foskinis, Stergios Vratolis, Maria I. Gini, Konstantinos Granakis, Anne-Claire Billault-Roux, Paraskevi Georgakaki, Olga Zografou, Prodromos Fetfatzis, Alexis Berne, Alexandros Papayannis, Konstantinos Eleftheridadis, Ottmar Möhler, and Athanasios Nenes
Atmos. Chem. Phys., 24, 9939–9974, https://doi.org/10.5194/acp-24-9939-2024, https://doi.org/10.5194/acp-24-9939-2024, 2024
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Ice nucleating particle (INP) concentrations are required for correct predictions of clouds and precipitation in a changing climate, but they are poorly constrained in climate models. We unravel source contributions to INPs in the eastern Mediterranean and find that biological particles are important, regardless of their origin. The parameterizations developed exhibit superior performance and enable models to consider biological-particle effects on INPs.
Alexandra Kuwano, Amato T. Evan, Blake Walkowiak, and Robert Frouin
Atmos. Chem. Phys., 24, 9843–9868, https://doi.org/10.5194/acp-24-9843-2024, https://doi.org/10.5194/acp-24-9843-2024, 2024
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The dust direct radiative effect is highly uncertain. Here we used new measurements collected over 3 years and during dust storms at a field site in a desert region in the southwestern United States to estimate the regional dust direct radiative effect. We also used novel soil mineralogy retrieved from an airborne spectrometer to estimate this parameter with model output. We find that, in this region, dust has a minimal net cooling effect on this region's climate.
Jutta Kesti, Ewan J. O'Connor, Anne Hirsikko, John Backman, Maria Filioglou, Anu-Maija Sundström, Juha Tonttila, Heikki Lihavainen, Hannele Korhonen, and Eija Asmi
Atmos. Chem. Phys., 24, 9369–9386, https://doi.org/10.5194/acp-24-9369-2024, https://doi.org/10.5194/acp-24-9369-2024, 2024
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The study combines aerosol particle measurements at the surface and vertical profiling of the atmosphere with a scanning Doppler lidar to investigate how particle transportation together with boundary layer evolution can affect particle and SO2 concentrations at the surface in the Arabian Peninsula region. The instrumentation enabled us to see elevated nucleation mode particle and SO2 concentrations at the surface when air masses transported from polluted areas are mixed in the boundary layer.
Jiangchuan Tao, Biao Luo, Weiqi Xu, Gang Zhao, Hanbin Xu, Biao Xue, Miaomiao Zhai, Wanyun Xu, Huarong Zhao, Sanxue Ren, Guangsheng Zhou, Li Liu, Ye Kuang, and Yele Sun
Atmos. Chem. Phys., 24, 9131–9154, https://doi.org/10.5194/acp-24-9131-2024, https://doi.org/10.5194/acp-24-9131-2024, 2024
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Using simultaneous measurements of DMA–CCNC, H(/V)TDMA, and DMA–SP2, impacts of primary emissions and secondary aerosol formations on changes in aerosol physicochemical properties were comprehensively investigated. It was found that intercomparisons among aerosol mixing-state parameters derived from different techniques can help us gain more insight into aerosol physical properties which, in turn, will aid the investigation of emission characteristics and secondary aerosol formation pathways.
Marco A. Franco, Rafael Valiati, Bruna A. Holanda, Bruno B. Meller, Leslie A. Kremper, Luciana V. Rizzo, Samara Carbone, Fernando G. Morais, Janaína P. Nascimento, Meinrat O. Andreae, Micael A. Cecchini, Luiz A. T. Machado, Milena Ponczek, Ulrich Pöschl, David Walter, Christopher Pöhlker, and Paulo Artaxo
Atmos. Chem. Phys., 24, 8751–8770, https://doi.org/10.5194/acp-24-8751-2024, https://doi.org/10.5194/acp-24-8751-2024, 2024
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The Amazon wet-season atmosphere was studied at the Amazon Tall Tower Observatory site, revealing vertical variations (between 60 and 325 m) in natural aerosols. Daytime mixing contrasted with nighttime stratification, with distinct rain-induced changes in aerosol populations. Notably, optical property recovery at higher levels was faster, while near-canopy aerosols showed higher scattering efficiency. These findings enhance our understanding of aerosol impacts on climate dynamics.
Lijing Chen, Lei Zhang, Yong She, Zhaoliang Zeng, Yu Zheng, Biao Tian, Wenqian Zhang, Zhaohui Liu, and Minghu Ding
EGUsphere, https://doi.org/10.5194/egusphere-2024-798, https://doi.org/10.5194/egusphere-2024-798, 2024
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AOD at Zhongshan Station varies seasonally, with lower values in summer and higher values in winter. Winter and spring AOD increases due to reduced fine mode particles, while summer and autumn increases are linked to particle growth. Duirnal AOD variation correlates positively with temperature but negatively with wind speed and humidity. Backward trajectory shows aerosols on high (low) AOD days primarily originate from the ocean (interior Antarctica).
Kristina Pistone, Eric M. Wilcox, Paquita Zuidema, Marco Giordano, James Podolske, Samuel E. LeBlanc, Meloë Kacenelenbogen, Steven G. Howell, and Steffen Freitag
Atmos. Chem. Phys., 24, 7983–8005, https://doi.org/10.5194/acp-24-7983-2024, https://doi.org/10.5194/acp-24-7983-2024, 2024
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The springtime southeast Atlantic atmosphere contains lots of smoke from continental fires. This smoke travels with water vapor; more smoke means more humidity. We use aircraft observations and models to describe how the values change through the season and over the region. We sort the atmosphere into different types by vertical structure and amount of smoke and humidity. Since our work shows how frequently these components coincide, it helps to better quantify heating effects over this region.
Yange Deng, Hiroshi Tanimoto, Kohei Ikeda, Sohiko Kameyama, Sachiko Okamoto, Jinyoung Jung, Young Jun Yoon, Eun Jin Yang, and Sung-Ho Kang
Atmos. Chem. Phys., 24, 6339–6357, https://doi.org/10.5194/acp-24-6339-2024, https://doi.org/10.5194/acp-24-6339-2024, 2024
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Black carbon (BC) aerosols play important roles in Arctic climate change, yet they are not well understood because of limited observational data. We observed BC mass concentrations (mBC) in the western Arctic Ocean during summer and early autumn 2016–2020. The mean mBC in 2019 was much higher than in other years. Biomass burning was likely the dominant BC source. Boreal fire BC transport occurring near the surface and/or in the mid-troposphere contributed to high-BC events in the Arctic Ocean.
Erin N. Raif, Sarah L. Barr, Mark D. Tarn, James B. McQuaid, Martin I. Daily, Steven J. Abel, Paul A. Barrett, Keith N. Bower, Paul R. Field, Kenneth S. Carslaw, and Benjamin J. Murray
EGUsphere, https://doi.org/10.5194/egusphere-2024-1502, https://doi.org/10.5194/egusphere-2024-1502, 2024
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Ice-nucleating particles (INPs) allow ice to form in clouds at temperatures warmer than -35°C. We measured INP concentrations over the Norwegian and Barents seas in weather events where cold air is ejected from the Arctic. These concentrations were among the highest measured in the Arctic and it is likely that the INPs were transported to the Arctic from distant regions. These results show it is important to consider hemispheric-scale INP processes to understand INP concentrations in the Arctic.
Fernando Rejano, Andrea Casans, Marta Via, Juan Andrés Casquero-Vera, Sonia Castillo, Hassan Lyamani, Alberto Cazorla, Elisabeth Andrews, Daniel Pérez-Ramírez, Andrés Alastuey, Francisco Javier Gómez-Moreno, Lucas Alados-Arboledas, Francisco José Olmo, and Gloria Titos
EGUsphere, https://doi.org/10.5194/egusphere-2024-1059, https://doi.org/10.5194/egusphere-2024-1059, 2024
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This study provides valuable insights to improve cloud condensation nuclei (CCN) estimations at a high-altitude remote site which is influenced by nearby urban pollution. Understanding the factors that affect CCN estimations is essential to improve the CCN data coverage worldwide and assess aerosol-cloud interactions in a global scale. This is crucial for improving climate models since aerosol-cloud interactions are the most important source of uncertainty in climate projections.
Máté Vörösmarty, Philip K. Hopke, and Imre Salma
Atmos. Chem. Phys., 24, 5695–5712, https://doi.org/10.5194/acp-24-5695-2024, https://doi.org/10.5194/acp-24-5695-2024, 2024
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The World Health Organization identified ultrafine particles, which make up most of the particle number concentrations, as a potential risk factor for humans. The sources of particle numbers are very different from those of the particulate matter mass. We performed source apportionment of size-segregated particle number concentrations over the diameter range of 6–1000 nm in Budapest for 11 full years. Six source types were identified, characterized and quantified.
Jerome D. Fast, Adam C. Varble, Fan Mei, Mikhail Pekour, Jason Tomlinson, Alla Zelenyuk, Art J. Sedlacek III, Maria Zawadowicz, and Louisa K. Emmons
EGUsphere, https://doi.org/10.5194/egusphere-2024-1349, https://doi.org/10.5194/egusphere-2024-1349, 2024
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Aerosol property measurements recently collected at the ground and by a research aircraft in central Argentina during the CACTI campaign exhibit large spatial and temporal variability. These measurements coupled with coincident meteorological information provide a valuable dataset needed to evaluate and improve model predictions of aerosols in a traditionally data sparse region of South America.
Gabriel Pereira Freitas, Ben Kopec, Kouji Adachi, Radovan Krejci, Dominic Heslin-Rees, Karl Espen Yttri, Alun Hubbard, Jeffrey M. Welker, and Paul Zieger
Atmos. Chem. Phys., 24, 5479–5494, https://doi.org/10.5194/acp-24-5479-2024, https://doi.org/10.5194/acp-24-5479-2024, 2024
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Bioaerosols can participate in ice formation within clouds. In the Arctic, where global warming manifests most, they may become more important as their sources prevail for longer periods of the year. We have directly measured bioaerosols within clouds for a full year at an Arctic mountain site using a novel combination of cloud particle sampling and single-particle techniques. We show that bioaerosols act as cloud seeds and may influence the presence of ice within clouds.
Andreas Petzold, Ulrich Bundke, Anca Hienola, Paolo Laj, Cathrine Lund Myhre, Alex Vermeulen, Angeliki Adamaki, Werner Kutsch, Valerie Thouret, Damien Boulanger, Markus Fiebig, Markus Stocker, Zhiming Zhao, and Ari Asmi
Atmos. Chem. Phys., 24, 5369–5388, https://doi.org/10.5194/acp-24-5369-2024, https://doi.org/10.5194/acp-24-5369-2024, 2024
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Easy and fast access to long-term and high-quality observational data is recognised as fundamental to environmental research and the development of climate forecasting and assessment services. We discuss the potential new directions in atmospheric sciences offered by the atmosphere-centric European research infrastructures ACTRIS, IAGOS, and ICOS, building on their capabilities for standardised provision of data through open access combined with tools and methods of data-intensive science.
Elise K. Wilbourn, Larissa Lacher, Carlos Guerrero, Hemanth S. K. Vepuri, Kristina Höhler, Jens Nadolny, Aidan D. Pantoya, Ottmar Möhler, and Naruki Hiranuma
Atmos. Chem. Phys., 24, 5433–5456, https://doi.org/10.5194/acp-24-5433-2024, https://doi.org/10.5194/acp-24-5433-2024, 2024
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Ambient ice particles were measured at terrestrial and temperate marine sites. Ice particles were more abundant in the former site, while the fraction of ice particles relative to total ambient particles, representing atmospheric ice nucleation efficiency, was higher in the latter site. Ice nucleation parameterizations were developed as a function of examined freezing temperatures from two sites for our study periods (autumn).
Ping Tian, Dantong Liu, Kang Hu, Yangzhou Wu, Mengyu Huang, Hui He, Jiujiang Sheng, Chenjie Yu, Dawei Hu, and Deping Ding
Atmos. Chem. Phys., 24, 5149–5164, https://doi.org/10.5194/acp-24-5149-2024, https://doi.org/10.5194/acp-24-5149-2024, 2024
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The results provide direct evidence of efficient droplet activation of black carbon (BC). The cloud condensation nuclei (CCN) activation fraction of BC was higher than for all particles, suggesting higher CCN activity of BC, even though its hygroscopicity is lower. Our research reveals that the evolution of BC's hygroscopicity and its CCN activation properties through atmospheric aging can be effectively characterized by the photochemical age.
Henriette Gebauer, Athena Augusta Floutsi, Moritz Haarig, Martin Radenz, Ronny Engelmann, Dietrich Althausen, Annett Skupin, Albert Ansmann, Cordula Zenk, and Holger Baars
Atmos. Chem. Phys., 24, 5047–5067, https://doi.org/10.5194/acp-24-5047-2024, https://doi.org/10.5194/acp-24-5047-2024, 2024
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Sulfate aerosol from the volcanic eruption at La Palma in 2021 was observed over Cabo Verde. We characterized the aerosol burden based on a case study of lidar and sun photometer observations. We compared the volcanic case to the typical background conditions (reference case) to quantify the volcanic pollution. We show the first ever measurements of the extinction coefficient, lidar ratio and depolarization ratio at 1064 nm for volcanic sulfate.
Cyrille Flamant, Jean-Pierre Chaboureau, Marco Gaetani, Kerstin Schepanski, and Paola Formenti
Atmos. Chem. Phys., 24, 4265–4288, https://doi.org/10.5194/acp-24-4265-2024, https://doi.org/10.5194/acp-24-4265-2024, 2024
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In the austral dry season, the atmospheric composition over southern Africa is dominated by biomass burning aerosols and terrigenous aerosols (so-called mineral dust). This study suggests that the radiative effect of biomass burning aerosols needs to be taken into account to properly forecast dust emissions in Namibia.
Boming Liu, Xin Ma, Jianping Guo, Renqiang Wen, Hui Li, Shikuan Jin, Yingying Ma, Xiaoran Guo, and Wei Gong
Atmos. Chem. Phys., 24, 4047–4063, https://doi.org/10.5194/acp-24-4047-2024, https://doi.org/10.5194/acp-24-4047-2024, 2024
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Accurate wind profile estimation, especially for the lowest few hundred meters of the atmosphere, is of great significance for the weather, climate, and renewable energy sector. We propose a novel method that combines the power-law method with the random forest algorithm to extend wind profiles beyond the surface layer. Compared with the traditional algorithm, this method has better stability and spatial applicability and can be used to obtain the wind profiles on different land cover types.
Gabriela R. Unfer, Luiz A. T. Machado, Paulo Artaxo, Marco A. Franco, Leslie A. Kremper, Mira L. Pöhlker, Ulrich Pöschl, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 3869–3882, https://doi.org/10.5194/acp-24-3869-2024, https://doi.org/10.5194/acp-24-3869-2024, 2024
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Amazonian aerosols and their interactions with precipitation were studied by understanding them in a 3D space based on three parameters that characterize the concentration and size distribution of aerosols. The results showed characteristic arrangements regarding seasonal and diurnal cycles, as well as when interacting with precipitation. The use of this 3D space appears to be a promising tool for aerosol population analysis and for model validation and parameterization.
Anil Kumar Mandariya, Ajit Ahlawat, Mohammed Haneef, Nisar Ali Baig, Kanan Patel, Joshua Apte, Lea Hildebrandt Ruiz, Alfred Wiedensohler, and Gazala Habib
Atmos. Chem. Phys., 24, 3627–3647, https://doi.org/10.5194/acp-24-3627-2024, https://doi.org/10.5194/acp-24-3627-2024, 2024
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The current study explores the temporal variation of size-selected particle hygroscopicity in Delhi for the first time. Here, we report that the high volume fraction contribution of ammonium chloride to aerosol governs the high aerosol hygroscopicity and associated liquid water content based on the experimental data. The episodically high ammonium chloride present in Delhi's atmosphere could lead to haze and fog formation under high relative humidity in the region.
Yueyue Cheng, Chao Liu, Jiandong Wang, Jiaping Wang, Zhouyang Zhang, Li Chen, Dafeng Ge, Caijun Zhu, Jinbo Wang, and Aijun Ding
Atmos. Chem. Phys., 24, 3065–3078, https://doi.org/10.5194/acp-24-3065-2024, https://doi.org/10.5194/acp-24-3065-2024, 2024
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Brown carbon (BrC), a light-absorbing aerosol, plays a pivotal role in influencing global climate. However, assessing BrC radiative effects remains challenging because the required observational data are hardly accessible. Here we develop a new BrC radiative effect estimation method combining conventional observations and numerical models. Our findings reveal that BrC absorbs up to a third of the sunlight at 370 nm that black carbon does, highlighting its importance in aerosol radiative effects.
Larissa Lacher, Michael P. Adams, Kevin Barry, Barbara Bertozzi, Heinz Bingemer, Cristian Boffo, Yannick Bras, Nicole Büttner, Dimitri Castarede, Daniel J. Cziczo, Paul J. DeMott, Romy Fösig, Megan Goodell, Kristina Höhler, Thomas C. J. Hill, Conrad Jentzsch, Luis A. Ladino, Ezra J. T. Levin, Stephan Mertes, Ottmar Möhler, Kathryn A. Moore, Benjamin J. Murray, Jens Nadolny, Tatjana Pfeuffer, David Picard, Carolina Ramírez-Romero, Mickael Ribeiro, Sarah Richter, Jann Schrod, Karine Sellegri, Frank Stratmann, Benjamin E. Swanson, Erik S. Thomson, Heike Wex, Martin J. Wolf, and Evelyn Freney
Atmos. Chem. Phys., 24, 2651–2678, https://doi.org/10.5194/acp-24-2651-2024, https://doi.org/10.5194/acp-24-2651-2024, 2024
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Aerosol particles that trigger ice formation in clouds are important for the climate system but are very rare in the atmosphere, challenging measurement techniques. Here we compare three cloud chambers and seven methods for collecting aerosol particles on filters for offline analysis at a mountaintop station. A general good agreement of the methods was found when sampling aerosol particles behind a whole air inlet, supporting their use for obtaining data that can be implemented in models.
Andrea Cuesta-Mosquera, Kristina Glojek, Griša Močnik, Luka Drinovec, Asta Gregorič, Martin Rigler, Matej Ogrin, Baseerat Romshoo, Kay Weinhold, Maik Merkel, Dominik van Pinxteren, Hartmut Herrmann, Alfred Wiedensohler, Mira Pöhlker, and Thomas Müller
Atmos. Chem. Phys., 24, 2583–2605, https://doi.org/10.5194/acp-24-2583-2024, https://doi.org/10.5194/acp-24-2583-2024, 2024
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This study evaluated the air pollution and climate impacts of residential-wood-burning particle emissions from a rural European site. The authors investigate the optical and physical properties that connect the aerosol emissions with climate by evaluating atmospheric radiative impacts via simple-forcing calculations. The study contributes to reducing the lack of information on the understanding of the optical properties of air pollution from anthropogenic sources.
Xiangxinyue Meng, Zhijun Wu, Jingchuan Chen, Yanting Qiu, Taomou Zong, Mijung Song, Jiyi Lee, and Min Hu
Atmos. Chem. Phys., 24, 2399–2414, https://doi.org/10.5194/acp-24-2399-2024, https://doi.org/10.5194/acp-24-2399-2024, 2024
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Our study revealed that particles predominantly exist in a semi-solid or solid state during clean winter days with RH below 30 %. However, a non-liquid to a liquid phase transition occurred when the aerosol liquid water (ALW) mass fraction surpassed 15 % (dry mass) at transition RH thresholds ranging from 40 % to 60 %. We also provide insights into the increasingly important roles of particle phase state variation and ALW in secondary particulate growth during haze formation in Beijing, China.
Bighnaraj Sarangi, Darrel Baumgardner, Ana Isabel Calvo, Benjamin Bolaños-Rosero, Roberto Fraile, Alberto Rodríguez-Fernández, Delia Fernández-González, Carlos Blanco-Alegre, Cátia Gonçalves, Estela D. Vicente, and Olga L. Mayol Bracero
EGUsphere, https://doi.org/10.5194/egusphere-2024-446, https://doi.org/10.5194/egusphere-2024-446, 2024
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Measurements of fluorescing aerosol particle properties have been made during two major African dust events, one over the island of Puerto Rico and the other over the city of León, Spain The measurements were with two Wideband Integrated Bioaerosol Spectrometers. A significant change in the background aerosol properties, at both locations, is observed when the dust is in the respective regions.
Yiming Wang, Haolin Wang, Yujie Qin, Xinqi Xu, Guowen He, Nanxi Liu, Shengjie Miao, Xiao Lu, Haichao Wang, and Shaojia Fan
Atmos. Chem. Phys., 24, 2267–2285, https://doi.org/10.5194/acp-24-2267-2024, https://doi.org/10.5194/acp-24-2267-2024, 2024
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We conducted a vertical measurement of winter PM2.5 using a mobile multi-lidar system in four cities. Combined with the surface PM2.5 data, the ERA5 reanalysis data, and GEOS-Chem simulations during Dec 2018–Feb 2019, we found that transport nocturnal PM2.5 enhancement by subsidence (T-NPES) events widely occurred with high frequencies in plains regions in eastern China but happened less often in basin regions like Xi’an and Chengdu. We propose a conceptual model of the T-NPES events.
Dominic Heslin-Rees, Peter Tunved, Johan Ström, Roxana Cremer, Paul Zieger, Ilona Riipinen, Annica M. L. Ekman, Konstantinos Eleftheriadis, and Radovan Krejci
Atmos. Chem. Phys., 24, 2059–2075, https://doi.org/10.5194/acp-24-2059-2024, https://doi.org/10.5194/acp-24-2059-2024, 2024
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Light-absorbing atmospheric particles (e.g. black carbon – BC) exert a warming effect on the Arctic climate. We show that the amount of particle light absorption decreased from 2002 to 2023. We conclude that in addition to reductions in emissions of BC, wet removal plays a role in the long-term reduction of BC in the Arctic, given the increase in surface precipitation experienced by air masses arriving at the site. The potential impact of biomass burning events is shown to have increased.
Julika Zinke, Ernst Douglas Nilsson, Piotr Markuszewski, Paul Zieger, Eva Monica Mårtensson, Anna Rutgersson, Erik Nilsson, and Matthew Edward Salter
Atmos. Chem. Phys., 24, 1895–1918, https://doi.org/10.5194/acp-24-1895-2024, https://doi.org/10.5194/acp-24-1895-2024, 2024
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We conducted two research campaigns in the Baltic Sea, during which we combined laboratory sea spray simulation experiments with flux measurements on a nearby island. To combine these two methods, we scaled the laboratory measurements to the flux measurements using three different approaches. As a result, we derived a parameterization that is dependent on wind speed and wave state for particles with diameters 0.015–10 μm. This parameterization is applicable to low-salinity waters.
Sarah Tinorua, Cyrielle Denjean, Pierre Nabat, Thierry Bourrianne, Véronique Pont, François Gheusi, and Emmanuel Leclerc
Atmos. Chem. Phys., 24, 1801–1824, https://doi.org/10.5194/acp-24-1801-2024, https://doi.org/10.5194/acp-24-1801-2024, 2024
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At a French high-altitude site, where many complex interactions between black carbon (BC), radiation, clouds and snow impact climate, 2 years of refractive BC (rBC) and aerosol optical and microphysical measurements have been made. We observed strong seasonal rBC properties variations, with an enhanced absorption in summer compared to winter. The combination of rBC emission sources, transport pathways, atmospheric dynamics and chemical processes explains the rBC light absorption seasonality.
Wenwen Ma, Rong Sun, Xiaoping Wang, Zheng Zong, Shizhen Zhao, Zeyu Sun, Chongguo Tian, Jianhui Tang, Song Cui, Jun Li, and Gan Zhang
Atmos. Chem. Phys., 24, 1509–1523, https://doi.org/10.5194/acp-24-1509-2024, https://doi.org/10.5194/acp-24-1509-2024, 2024
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This is the first report of long-term atmospheric PAH monitoring around the Bohai Sea. The results showed that the concentrations of PAHs in the atmosphere around the Bohai Sea decreased from June 2014 to May 2019, especially the concentrations of highly toxic PAHs. This indicates that the contributions from PAH sources changed to a certain extent in different areas, and it also led to reductions in the related health risk and medical costs following pollution prevention and control.
Mary C. Robinson, Kaitlin Schueth, and Karin Ardon-Dryer
EGUsphere, https://doi.org/10.5194/egusphere-2024-113, https://doi.org/10.5194/egusphere-2024-113, 2024
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On February 26, 2023, New Mexico and West Texas were impacted by a severe dust storm. 21 meteorological stations and 19 PM2.5 and PM10 stations were used to analyze this dust storm. Dust articles were in the air for 18 hours, and dust storm conditions lasted up to 65 minutes. Hourly PM2.5 and PM10 concentrations were up to 518.4 and 9,983 µg m-3, respectively. For Lubbock, Texas the maximum PM2.5 concentrations were the highest ever recorded.
Silke Groß, Volker Freudenthaler, Moritz Haarig, Albert Ansmann, Carlos Toledano, David Mateos, Petra Seibert, Rodanthi-Elisavet Mamouri, Argyro Nisantzi, Josef Gasteiger, Maximilian Dollner, Anne Tipka, Manuel Schöberl, Marilena Teri, and Bernadett Weinzierl
EGUsphere, https://doi.org/10.5194/egusphere-2024-140, https://doi.org/10.5194/egusphere-2024-140, 2024
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Aerosols contribute to the largest uncertainties in climate change predictions. Especially absorbing aerosols propose difficulties in our understanding. The eastern Mediterranean is a hot spot for aerosols with natural and anthropogenic contributions. We present lidar measurements performed during the A-LIFE field experiment to characterize aerosols and aerosol mixtures. We extend current classification and separation schemes and compare different classification schemes.
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