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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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
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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
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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
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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)
Phase matrix characterization of long-range-transported Saharan dust using multiwavelength-polarized polar imaging nephelometry
Measurement report: The influence of particle number size distribution and hygroscopicity on the microphysical properties of cloud droplets at a mountain site
Measurement report: Long-term assessment of primary and secondary organic aerosols in the Shanghai megacity throughout China's Clean Air actions since 2010
The evolution of aerosol mixing state derived from a field campaign in Beijing: implications for particle aging timescales in urban atmospheres
Measurement report: Size-resolved particle effective density measured by an AAC-SMPS and implications for chemical composition
Measurement report: Aircraft observations of aerosol and microphysical quantities of stratocumulus in autumn over Guangxi Province, China – daylight variation, vertical distribution, and aerosol–cloud interactions
Hygroscopic aerosols amplify longwave downward radiation in the Arctic
Measurement report: Aerosol and cloud nuclei properties along the Central and Northern Great Barrier Reef: Impact of continental emissions
Measurement report: Optical and structural properties of atmospheric water-soluble organic carbon in China – insights from multi-site spectroscopic measurements
Measurement report: The variation properties of aerosol hygroscopic growth related to chemical composition during new particle formation days in a coastal city of Southeast China
In situ vertical observations of the layered structure of air pollution in a continental high-latitude urban boundary layer during winter
Size-resolved hygroscopicity and volatility properties of ambient urban aerosol particles measured by a volatility hygroscopicity tandem differential mobility analyzer system in Beijing
Terrestrial runoff is an important source of biological ice-nucleating particles in Arctic marine systems
Characterization of aerosol over the eastern Mediterranean by polarization-sensitive Raman lidar measurements during A-LIFE – aerosol type classification and type separation
Aerosol spectral optical properties in the Paris urban area and its peri-urban and forested surroundings during summer 2022 from ACROSS surface observations
Measurement report: An investigation of the spatiotemporal variability in aerosols in the mountainous terrain of the upper Colorado River basin using SAIL-Net
Contributions of the synoptic meteorology to the seasonal cloud condensation nuclei cycle over the Southern Ocean
Measurement report: Cloud condensation nuclei (CCN) activity in the South China Sea from shipborne observations during the summer and winter of 2021 – seasonal variation and anthropogenic influence
Differential characterization of air ions in boreal forest of Finland and megacity of eastern China
Source-Dependent Optical Properties and Molecular Characteristics of Atmospheric Brown Carbon
On-road vehicle emission measurements show a significant reduction of black carbon and nitrogen oxides emissions in Euro6c and 6d diesel-powered cars
Measurement report: A comparative analysis of an intensive incursion of fluorescing African dust particles over Puerto Rico and another over Spain
Measurement report: Analysis of aerosol optical depth variation at Zhongshan Station in Antarctica
External particle mixing influences hygroscopicity in a sub-urban area
Long-term observations of black carbon and carbon monoxide in the Poker Flat Research Range, central Alaska, with a focus on forest wildfire emissions
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
Aerosol hygroscopicity over the southeast Atlantic Ocean during the biomass burning season – Part 1: From the perspective of scattering enhancement
Spatial, temporal, and meteorological impact of the 26 February 2023 dust storm: increase in particulate matter concentrations across New Mexico and West Texas
Large spatiotemporal variability in aerosol properties over central Argentina during the CACTI field campaign
Microphysical properties of refractory black carbon aerosols for different air masses at a central European background site
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
Multi-year black carbon observations and modeling close to the largest gas flaring and wildfire regions (Western Siberian Arctic)
Strong influence of Black Carbon on aerosol optical properties in Central Amazonia during the fire season
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
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
Elena Bazo, Daniel Pérez-Ramírez, Antonio Valenzuela, J. Vanderlei Martins, Gloria Titos, Alberto Cazorla, Fernando Rejano, Diego Patrón, Arlett Díaz-Zurita, Francisco José García-Izquierdo, David Fuertes, Lucas Alados-Arboledas, and Francisco José Olmo
Atmos. Chem. Phys., 25, 6325–6352, https://doi.org/10.5194/acp-25-6325-2025, https://doi.org/10.5194/acp-25-6325-2025, 2025
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This works analyzes the aerosol scattering phase function for transported Saharan dust to the city of Granada – located in southwestern Europe. We use the novel technique polar imaging nephelometry that helps to determine the phase functions using a CMOS camera. The capability of measuring with polarized light helps to infer new properties about the mixture of Saharan dust particles with those of anthropogenic origin.
Xiaojing Shen, Quan Liu, Junying Sun, Wanlin Kong, Qianli Ma, Bing Qi, Lujie Han, Yangmei Zhang, Linlin Liang, Lei Liu, Shuo Liu, Xinyao Hu, Jiayuan Lu, Aoyuan Yu, Huizheng Che, and Xiaoye Zhang
Atmos. Chem. Phys., 25, 5711–5725, https://doi.org/10.5194/acp-25-5711-2025, https://doi.org/10.5194/acp-25-5711-2025, 2025
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In this work, an automatic switched inlet system was developed and employed to investigate the aerosols and cloud droplets at a mountain site with frequent cloud processes. It showed different characteristics of cloud residual and interstitial particles. Stronger particle hygroscopicity reduced liquid water content and smaller cloud droplet diameters. This investigation contributes to understanding aerosol–cloud interactions by assessing the impact of aerosol particles on cloud microphysics.
Haifeng Yu, Yunhua Chang, Lin Cheng, Yusen Duan, and Jianlin Hu
Atmos. Chem. Phys., 25, 5355–5369, https://doi.org/10.5194/acp-25-5355-2025, https://doi.org/10.5194/acp-25-5355-2025, 2025
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This study presents long-term measurements and comprehensive analysis of carbonaceous aerosols in fine particles in Shanghai. We further estimated primary and secondary carbon levels, examining their temporal variations on interannual, monthly, seasonal, and diurnal scales. Through rigorous statistical analysis and correlation studies with meteorological parameters and pollutant concentrations, the origins, formation mechanisms, and spatial distribution patterns of secondary organic carbon were elucidated.
Jieyao Liu, Fang Zhang, Jingye Ren, Lu Chen, Anran Zhang, Zhe Wang, Songjian Zou, Honghao Xu, and Xingyan Yue
Atmos. Chem. Phys., 25, 5075–5086, https://doi.org/10.5194/acp-25-5075-2025, https://doi.org/10.5194/acp-25-5075-2025, 2025
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Particle mixing states and aging timescales are important for the evaluation of aerosol climate effects, but they are poorly parameterized in current models. We unravel the evolution of real-time mixing states and the aging timescale of size-resolved particles based on field measurements in urban Beijing. This study provides an observational basis for accurately parameterizing the aging timescale of aerosol particles in climate models.
Yao Song, Jing Wei, Wenlong Zhao, Jinmei Ding, Xiangyu Pei, Fei Zhang, Zhengning Xu, Ruifang Shi, Ya Wei, Lu Zhang, Lingling Jin, and Zhibin Wang
Atmos. Chem. Phys., 25, 4755–4766, https://doi.org/10.5194/acp-25-4755-2025, https://doi.org/10.5194/acp-25-4755-2025, 2025
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This study investigates the size-resolved effective density (ρeff) of aerosol particles in Hangzhou using a tandem aerodynamic aerosol classifier and scanning mobility particle sizer system. The ρeff values ranged from 1.47 to 1.63 g cm-3, increasing with particle diameter. The relationship between ρeff and the particle diameter varies due to differences in the chemical composition of the particles. A new method to derive the size-resolved chemical composition of particles from ρeff is proposed.
Sihan Liu, Honglei Wang, Delong Zhao, Wei Zhou, Yuanmou Du, Zhengguo Zhang, Peng Cheng, Tianliang Zhao, Yue Ke, Zihao Wu, and Mengyu Huang
Atmos. Chem. Phys., 25, 4151–4165, https://doi.org/10.5194/acp-25-4151-2025, https://doi.org/10.5194/acp-25-4151-2025, 2025
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To understand the effect of aerosols on the vertical distribution of stratocumulus microphysical quantities in southwest China, the daily variation characteristics and formation mechanism of the vertical profiles of stratocumulus microphysical characteristics in this region were described using the data of nine cloud-crossing aircraft observations over Guangxi from 10 October to 3 November 2020.
Denghui Ji, Mathias Palm, Matthias Buschmann, Kerstin Ebell, Marion Maturilli, Xiaoyu Sun, and Justus Notholt
Atmos. Chem. Phys., 25, 3889–3904, https://doi.org/10.5194/acp-25-3889-2025, https://doi.org/10.5194/acp-25-3889-2025, 2025
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Our study explores how certain aerosols, like sea salt, affect infrared heat radiation in the Arctic, potentially speeding up warming. We used advanced technology to measure aerosol composition and found that these particles grow with humidity, significantly increasing their heat-trapping effect in the infrared region, especially in winter. Our findings suggest these aerosols could be a key factor in Arctic warming, emphasizing the importance of understanding aerosols for climate prediction.
E. Johanna Horchler, Joel Alroe, Luke Harrison, Luke Cravigan, Daniel P. Harrison, and Zoran D. Ristovski
EGUsphere, https://doi.org/10.5194/egusphere-2025-465, https://doi.org/10.5194/egusphere-2025-465, 2025
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Aerosols play a role in global climate by interacting with incoming solar radiation and by taking up water vapour from the atmosphere to form clouds. Enhancing local-scale cloud cover can reduce sea surface temperatures. Coral bleaching events increased in the Great Barrier Reef (GBR) as sea surface temperatures rise. Our study found that the number of aerosols and the cloud forming ability over the GBR increased if the aerosols were transported from inland Australia rather than the ocean.
Haibiao Chen, Caiqing Yan, Liubin Huang, Lin Du, Yang Yue, Xinfeng Wang, Qingcai Chen, Mingjie Xie, Junwen Liu, Fengwen Wang, Shuhong Fang, Qiaoyun Yang, Hongya Niu, Mei Zheng, Yan Wu, and Likun Xue
Atmos. Chem. Phys., 25, 3647–3667, https://doi.org/10.5194/acp-25-3647-2025, https://doi.org/10.5194/acp-25-3647-2025, 2025
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A comprehensive understanding of the optical properties of brown carbon (BrC) is essential to accurately assess its climatic effects. Based on multi-site spectroscopic measurements, this study demonstrated the significant spatial heterogeneity in the optical and structural properties of water-soluble organic carbon (WSOC) in different regions of China and revealed factors affecting WSOC light absorption and the relationship between fluorophores and light absorption of WSOC.
Lingjun Li, Mengren Li, Xiaolong Fan, Yuping Chen, Ziyi Lin, Anqi Hou, Siqing Zhang, Ronghua Zheng, and Jinsheng Chen
Atmos. Chem. Phys., 25, 3669–3685, https://doi.org/10.5194/acp-25-3669-2025, https://doi.org/10.5194/acp-25-3669-2025, 2025
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Here, we show differences and variations in the aerosol scattering hygroscopic growth factor (f(RH)) between new particle formation (NPF) and non-NPF days and the effect of aerosol chemical compositions on f(RH) in Xiamen with in situ observations. The findings are helpful for the further understanding of aerosol hygroscopicity in a coastal city and the use of hygroscopic growth factors in models of air quality and climate change.
Roman Pohorsky, Andrea Baccarini, Natalie Brett, Brice Barret, Slimane Bekki, Gianluca Pappaccogli, Elsa Dieudonné, Brice Temime-Roussel, Barbara D'Anna, Meeta Cesler-Maloney, Antonio Donateo, Stefano Decesari, Kathy S. Law, William R. Simpson, Javier Fochesatto, Steve R. Arnold, and Julia Schmale
Atmos. Chem. Phys., 25, 3687–3715, https://doi.org/10.5194/acp-25-3687-2025, https://doi.org/10.5194/acp-25-3687-2025, 2025
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This study presents an analysis of vertical measurements of pollution in an Alaskan city during winter. It investigates the relationship between the atmospheric structure and the layering of aerosols and trace gases. Results indicate an overall very shallow surface mixing layer. The height of this layer is strongly influenced by a local shallow wind. The study also provides information on the pollution chemical composition at different altitudes, including pollution signatures from power plants.
Aoyuan Yu, Xiaojing Shen, Qianli Ma, Jiayuan Lu, Xinyao Hu, Yangmei Zhang, Quan Liu, Linlin Liang, Lei Liu, Shuo Liu, Hongfei Tong, Huizheng Che, Xiaoye Zhang, and Junying Sun
Atmos. Chem. Phys., 25, 3389–3412, https://doi.org/10.5194/acp-25-3389-2025, https://doi.org/10.5194/acp-25-3389-2025, 2025
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In this work, we utilized a volatility hygroscopicity tandem differential mobility analyzer (VH-TDMA) to investigate, for the first time, the hygroscopicity and volatility of submicron aerosols, as well as their hygroscopicity after heating, in urban Beijing during the autumn of 2023. We analyzed the size-resolved characteristics of hygroscopicity and volatility, the relationship between hygroscopic and volatile properties, and the hygroscopicity of heated submicron aerosols.
Corina Wieber, Lasse Z. Jensen, Leendert Vergeynst, Lorenz Meire, Thomas Juul-Pedersen, Kai Finster, and Tina Šantl-Temkiv
Atmos. Chem. Phys., 25, 3327–3346, https://doi.org/10.5194/acp-25-3327-2025, https://doi.org/10.5194/acp-25-3327-2025, 2025
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The Arctic region is subject to profound changes due to a warming climate. Ice-nucleating particles (INPs) in the seawater can get transported to the atmosphere and impact cloud formation. However, the sources of characteristics of INPs in the marine areas are poorly understood. We investigated the INPs in seawater from Greenlandic fjords and identified a seasonal variability, with highly active INPs originating from terrestrial sources such as glacial and soil runoff.
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
Atmos. Chem. Phys., 25, 3191–3211, https://doi.org/10.5194/acp-25-3191-2025, https://doi.org/10.5194/acp-25-3191-2025, 2025
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Aerosols contribute to the largest uncertainties in climate change predictions. The eastern Mediterranean is a hotspot for aerosols with natural and anthropogenic contributions. We present lidar measurements performed during A-LIFE (Absorbing aerosol layers in a changing climate: aging, lifetime and dynamics) to characterize aerosols and aerosol mixtures. We extend current lidar classification and separation schemes and compare them to classification schemes using different methods.
Ludovico Di Antonio, Claudia Di Biagio, Paola Formenti, Aline Gratien, Vincent Michoud, Christopher Cantrell, Astrid Bauville, Antonin Bergé, Mathieu Cazaunau, Servanne Chevaillier, Manuela Cirtog, Patrice Coll, Barbara D'Anna, Joel F. de Brito, David O. De Haan, Juliette R. Dignum, Shravan Deshmukh, Olivier Favez, Pierre-Marie Flaud, Cecile Gaimoz, Lelia N. Hawkins, Julien Kammer, Brigitte Language, Franck Maisonneuve, Griša Močnik, Emilie Perraudin, Jean-Eudes Petit, Prodip Acharja, Laurent Poulain, Pauline Pouyes, Eva Drew Pronovost, Véronique Riffault, Kanuri I. Roundtree, Marwa Shahin, Guillaume Siour, Eric Villenave, Pascal Zapf, Gilles Foret, Jean-François Doussin, and Matthias Beekmann
Atmos. Chem. Phys., 25, 3161–3189, https://doi.org/10.5194/acp-25-3161-2025, https://doi.org/10.5194/acp-25-3161-2025, 2025
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The spectral complex refractive index (CRI) and single scattering albedo were retrieved from submicron aerosol measurements at three sites within the greater Paris area during the ACROSS field campaign (June–July 2022). Measurements revealed urban emission impact on surrounding areas. CRI full period averages at 520 nm were 1.41 – 0.037i (urban), 1.52 – 0.038i (peri-urban), and 1.50 – 0.025i (rural). Organic aerosols dominated the aerosol mass and contributed up to 22 % of absorption at 370 nm.
Leah D. Gibson, Ezra J. T. Levin, Ethan Emerson, Nick Good, Anna Hodshire, Gavin McMeeking, Kate Patterson, Bryan Rainwater, Tom Ramin, and Ben Swanson
Atmos. Chem. Phys., 25, 2745–2762, https://doi.org/10.5194/acp-25-2745-2025, https://doi.org/10.5194/acp-25-2745-2025, 2025
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From fall 2021 to summer 2023, SAIL-Net, a network of six aerosol measurement nodes, was deployed in the East River watershed (Colorado, USA) to study aerosol variability across space and time in mountainous terrain. We found that aerosol variability is influenced by elevation differences, with the most representative site in the region changing seasonally, suggesting aerosol spatial variability also varies seasonally. This work offers a blueprint for future studies in other mountainous regions.
Tahereh Alinejadtabrizi, Yi Huang, Francisco Lang, Steven Siems, Michael Manton, Luis Ackermann, Melita Keywood, Ruhi Humphries, Paul Krummel, Alastair Williams, and Greg Ayers
Atmos. Chem. Phys., 25, 2631–2648, https://doi.org/10.5194/acp-25-2631-2025, https://doi.org/10.5194/acp-25-2631-2025, 2025
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Clouds over the Southern Ocean are crucial to Earth's energy balance, but understanding the factors that control them is complex. Our research examines how weather patterns affect tiny particles called cloud condensation nuclei (CCN), which influence cloud properties. Using data from Kennaook / Cape Grim, we found that winter air from Antarctica brings cleaner conditions with lower CCN, while summer patterns from Australia transport more particles. Precipitation also helps reduce CCN in winter.
Hengjia Ou, Mingfu Cai, Yongyun Zhang, Xue Ni, Baoling Liang, Qibin Sun, Shixin Mai, Cuizhi Sun, Shengzhen Zhou, Haichao Wang, Jiaren Sun, and Jun Zhao
Atmos. Chem. Phys., 25, 2495–2513, https://doi.org/10.5194/acp-25-2495-2025, https://doi.org/10.5194/acp-25-2495-2025, 2025
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Two shipborne observations in the South China Sea (SCS) in summer and winter 2021 were conducted. Our study found aerosol hygroscopicity is higher in the SCS in summer than winter, with significant influences from various terrestrial air masses. Aerosol size distribution had a stronger effect on activation ratio than aerosol hygroscopicity in summer and vice versa in winter. Our study provides valuable information to enhance our understanding of cloud condensation nuclei activities in the SCS.
Tinghan Zhang, Ximeng Qi, Janne Lampilahti, Liangduo Chen, Xuguang Chi, Wei Nie, Xin Huang, Zehao Zou, Wei Du, Tom Kokkonen, Tuukka Petäjä, Katrianne Lehtipalo, Veli-Matti Kerminen, Aijun Ding, and Markku Kulmala
EGUsphere, https://doi.org/10.5194/egusphere-2024-3370, https://doi.org/10.5194/egusphere-2024-3370, 2025
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By comparing air ions at two “flagship” sites —the SMEAR II site in the boreal forest of Finland and the SORPES site in a megacity in eastern China—we characterized ion concentrations and their roles in new particle formation (NPF) across contrasting environments. The ion-induced fraction was much higher in clean areas. However, earlier activation of charged particles and high ion-induced fraction during quiet NPF at SORPES imply a non-negligible role for ion-induced NPF in polluted areas.
Jinghao Zhai, Yin Zhang, Pengfei Liu, Yujie Zhang, Antai Zhang, Yaling Zeng, Baohua Cai, Jingyi Zhang, Chunbo Xing, Honglong Yang, Xiaofei Wang, Jianhuai Ye, Chen Wang, Tzung-May Fu, Lei Zhu, Huizhong Shen, Shu Tao, and Xin Yang
EGUsphere, https://doi.org/10.5194/egusphere-2025-463, https://doi.org/10.5194/egusphere-2025-463, 2025
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Our findings show that BrC's optical properties vary by source. Secondary BrC from ozone pollution had the lowest absorption but highest wavelength dependence, while BrC from biomass combustion had the highest absorption with the lowest wavelength dependence. Molecular analysis indicated that CHON species from biomass burning had the strongest light absorption. These insights enhance the accuracy of climate models by highlighting source-specific optical properties of BrC.
Irena Ježek Brecelj, Asta Gregorič, Lucijan Zgonik, Tjaša Rutar, Matic Ivančič, Balint Alfoldy, Griša Močnik, and Martin Rigler
EGUsphere, https://doi.org/10.5194/egusphere-2024-3553, https://doi.org/10.5194/egusphere-2024-3553, 2025
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Following a major car industry scandal involving diesel emissions tests, Europe introduced new testing procedures. However, concerns remained about their effectiveness. Our independent study examined real-world vehicle emissions and revealed encouraging findings: modern diesel cars perform as well as, or even better than, gasoline cars in terms of nitrogen oxides emissions. We found the same pattern for soot particles, challenging common perceptions about diesel's environmental impact.
Bighnaraj Sarangi, Darrel Baumgardner, Ana Isabel Calvo, Benjamin Bolaños-Rosero, Roberto Fraile, Alberto Rodríguez-Fernández, Delia Fernández-González, Carlos Blanco-Alegre, Cátia Gonçalves, Estela D. Vicente, and Olga L. Mayol-Bracero
Atmos. Chem. Phys., 25, 843–865, https://doi.org/10.5194/acp-25-843-2025, https://doi.org/10.5194/acp-25-843-2025, 2025
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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 made with two wideband integrated bioaerosol spectrometers. A significant change in the background aerosol properties, at both locations, is observed when the dust is in the respective regions.
Lijing Chen, Lei Zhang, Yong She, Zhaoliang Zeng, Yu Zheng, Biao Tian, Wenqian Zhang, Zhaohui Liu, Huizheng Che, and Minghu Ding
Atmos. Chem. Phys., 25, 727–739, https://doi.org/10.5194/acp-25-727-2025, https://doi.org/10.5194/acp-25-727-2025, 2025
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Aerosol optical depth (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. Diurnal AOD variation correlates positively with temperature but negatively with wind speed and humidity. Backward trajectories show that aerosols on high-AOD (low-AOD) days primarily originate from the ocean (interior Antarctica).
Shravan Deshmukh, Laurent Poulain, Birgit Wehner, Silvia Henning, Jean-Eudes Petit, Pauline Fombelle, Olivier Favez, Hartmut Herrmann, and Mira Pöhlker
Atmos. Chem. Phys., 25, 741–758, https://doi.org/10.5194/acp-25-741-2025, https://doi.org/10.5194/acp-25-741-2025, 2025
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Aerosol hygroscopicity has been investigated at a 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.
Takeshi Kinase, Fumikazu Taketani, Masayuki Takigawa, Chunmao Zhu, Yongwon Kim, Petr Mordovskoi, and Yugo Kanaya
Atmos. Chem. Phys., 25, 143–156, https://doi.org/10.5194/acp-25-143-2025, https://doi.org/10.5194/acp-25-143-2025, 2025
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Boreal forest wildfires in interior Alaska represent an important black carbon (BC) source for the Arctic and surrounding regions. We observed BC and carbon monoxide (CO) concentrations in the Poker Flat Research Range since 2016 and found a positive correlation between the observed BC / ∆CO ratio and fire radiative power (FRP) observed in Alaska and Canada. Our finding suggests the BC emission factor and/or inventory could be potentially improved by using FRP.
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
Atmos. Chem. Phys., 24, 14045–14072, https://doi.org/10.5194/acp-24-14045-2024, https://doi.org/10.5194/acp-24-14045-2024, 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. 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
Atmos. Chem. Phys., 24, 13865–13888, https://doi.org/10.5194/acp-24-13865-2024, https://doi.org/10.5194/acp-24-13865-2024, 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 on a global scale. This is crucial for improving climate models, since aerosol–cloud interactions are the most important source of uncertainty in climate projections.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Junying Sun, Ye Kuang, Paola Formenti, and Steven G. Howell
Atmos. Chem. Phys., 24, 13849–13864, https://doi.org/10.5194/acp-24-13849-2024, https://doi.org/10.5194/acp-24-13849-2024, 2024
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Using airborne measurements over the southeast Atlantic Ocean, we examined how much moisture aerosols take up during Africa’s biomass burning season. Our study revealed the important role of organic aerosols and introduced a predictive model for moisture uptake, accounting for organics, sulfate, and black carbon, summarizing results from various campaigns. These findings improve our understanding of aerosol–moisture interactions and their radiative effects in this climatically critical region.
Mary C. Robinson, Kaitlin Schueth, and Karin Ardon-Dryer
Atmos. Chem. Phys., 24, 13733–13750, https://doi.org/10.5194/acp-24-13733-2024, https://doi.org/10.5194/acp-24-13733-2024, 2024
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On 26 February 2023, New Mexico and West Texas were impacted by a severe dust storm. To analyze this storm, 28 meteorological stations and 19 PM2.5 and PM10 stations were used. Dust particles were in the air for 16 h, and dust storm conditions lasted for up to 120 min. Hourly PM2.5 and PM10 concentrations were up to 518 and 9983 µg m−3, respectively. For Lubbock, Texas, the maximum PM2.5 concentrations were the highest ever recorded.
Jerome D. Fast, Adam C. Varble, Fan Mei, Mikhail Pekour, Jason Tomlinson, Alla Zelenyuk, Art J. Sedlacek III, Maria Zawadowicz, and Louisa Emmons
Atmos. Chem. Phys., 24, 13477–13502, https://doi.org/10.5194/acp-24-13477-2024, https://doi.org/10.5194/acp-24-13477-2024, 2024
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Aerosol property measurements recently collected on the ground and by a research aircraft in central Argentina during the Cloud, Aerosol, and Complex Terrain Interactions (CACTI) campaign exhibit large spatial and temporal variability. These measurements coupled with coincident meteorological information provide a valuable data set needed to evaluate and improve model predictions of aerosols in a traditionally data-sparse region of South America.
Yifan Yang, Thomas Müller, Laurent Poulain, Samira Atabakhsh, Bruna A. Holanda, Jens Voigtländer, Shubhi Arora, and Mira L. Pöhlker
EGUsphere, https://doi.org/10.5194/egusphere-2024-3539, https://doi.org/10.5194/egusphere-2024-3539, 2024
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Black carbon (BC) is the major atmospheric aerosol that can absorb light and influence climate. We measured the physical properties of BC at a background site in Germany. In summer, BC particles were smaller and the mixture with other atmospheric components occurred during the daytime. In winter, emissions from residential heating significantly influenced BC's properties. Understanding these characteristics of BC can help improve aerosol optics simulation accuracy.
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.
Olga B. Popovicheva, Marina A. Chichaeva, Nikolaos Evangeliou, Sabine Eckhardt, Evangelia Diapouli, and Nikolay S. Kasimov
EGUsphere, https://doi.org/10.5194/egusphere-2024-3124, https://doi.org/10.5194/egusphere-2024-3124, 2024
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High-quality measurements of light-absorbing carbon were performed at the polar aerosol station "Island Bely” (Western Siberian Arctic) from 2019 to 2022. The maximum light absorption coefficients were seen in summer due to gas flaring contribution, which is the most significant source in the region. However, the increasing Siberian wildfires had a special share in carbon contribution to this high Arctic station with a persistent smoke layer extending over the whole troposphere in summer.
Rafael Stern, Joel F. de Brito, Samara Carbone, Luciana Varanda Rizzo, Jonathan Daniel Muller, and Paulo Artaxo
EGUsphere, https://doi.org/10.5194/egusphere-2024-3339, https://doi.org/10.5194/egusphere-2024-3339, 2024
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Our work reveals the impact of forest fires on climate. We found that particles related to direct emissions from fires, beyond the well-known effect of absorbing light and thus heating the atmosphere, are also very efficient in scattering light, which causes an atmospheric cooling effect. In our remote study site, most of the particles presented a different chemical composition then particles directly emitted by the fires, but those were the main responsible for total light extinction.
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.
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.
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