Articles | Volume 14, issue 14
https://doi.org/10.5194/acp-14-7397-2014
© 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-14-7397-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Uptake of HO2 radicals onto Arizona test dust particles using an aerosol flow tube
P. S. J. Matthews
School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
M. T. Baeza-Romero
Escuela de Ingeniería Industrial de Toledo, Universidad de Castilla la Mancha, Avenida Carlos III s/n Real Fábrica de Armas, Toledo, 45071, Spain
L. K. Whalley
School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
National Centre for Atmospheric Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
D. E. Heard
School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
National Centre for Atmospheric Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
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Joanna E. Dyson, 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, Stephen D. Worrall, Asan Bacak, Archit Mehra, Thomas J. Bannan, Hugh Coe, Carl J. Percival, Bin Ouyang, C. Nicholas Hewitt, Roderic L. Jones, Leigh R. Crilley, Louisa J. Kramer, W. Joe F. Acton, William J. Bloss, Supattarachai Saksakulkrai, Jingsha Xu, Zongbo Shi, Roy M. Harrison, Simone Kotthaus, Sue Grimmond, Yele Sun, Weiqi Xu, Siyao Yue, Lianfang Wei, Pingqing Fu, Xinming Wang, Stephen R. Arnold, and Dwayne E. Heard
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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The hydroxyl (OH) and closely coupled hydroperoxyl (HO2) radicals are vital for their role in the removal of atmospheric pollutants. In less polluted regions, atmospheric models over-predict HO2 concentrations. In this modelling study, the impact of heterogeneous uptake of HO2 onto aerosol surfaces on radical concentrations and the ozone production regime in Beijing in the summertime is investigated, and the implications for emissions policies across China are considered.
Matilda A. Pimlott, Richard J. Pope, Brian J. Kerridge, Barry G. Latter, Diane S. Knappett, Dwayne E. Heard, Lucy J. Ventress, Richard Siddans, Wuhu Feng, and Martyn P. Chipperfield
Atmos. Chem. Phys., 22, 10467–10488, https://doi.org/10.5194/acp-22-10467-2022, https://doi.org/10.5194/acp-22-10467-2022, 2022
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We present a new method to derive global information of the hydroxyl radical (OH), an important atmospheric oxidant. OH controls the lifetime of trace gases important to air quality and climate. We use satellite observations of ozone, carbon monoxide, methane and water vapour in a simple expression to derive OH around 3–4 km altitude. The derived OH compares well to model and aircraft OH data. We then apply the method to 10 years of satellite data to study the inter-annual variability of OH.
Marios Panagi, Roberto Sommariva, Zoë L. Fleming, Paul S. Monks, Gongda Lu, Eloise A. Marais, James R. Hopkins, Alastair C. Lewis, Qiang Zhang, James D. Lee, Freya A. Squires, Lisa K. Whalley, Eloise J. Slater, Dwayne E. Heard, Robert Woodward-Massey, Chunxiang Ye, and Joshua D. Vande Hey
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-379, https://doi.org/10.5194/acp-2022-379, 2022
Revised manuscript not accepted
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A dispersion model and a box model were combined to investigate the evolution of VOCs in Beijing once they are emitted from anthropogenic sources. It was determined that during the winter time the VOC concentrations in Beijing are driven predominantly by sources within Beijing and by a combination of transport and chemistry during the summer. Furthermore, the results in the paper highlight the need for a season specific policy.
Hannah Walker, Daniel Stone, Trevor Ingham, Sina Hackenberg, Danny Cryer, Shalini Punjabi, Katie Read, James Lee, Lisa Whalley, Dominick V. Spracklen, Lucy J. Carpenter, Steve R. Arnold, and Dwayne E. Heard
Atmos. Chem. Phys., 22, 5535–5557, https://doi.org/10.5194/acp-22-5535-2022, https://doi.org/10.5194/acp-22-5535-2022, 2022
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Glyoxal is a ubiquitous reactive organic compound in the atmosphere, which may form organic aerosol and impact the atmosphere's oxidising capacity. There are limited measurements of glyoxal's abundance in the remote marine atmosphere. We made new measurements of glyoxal using a highly sensitive technique over two 4-week periods in the tropical Atlantic atmosphere. We show that daytime measurements are mostly consistent with our chemical understanding but a potential missing source at night.
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
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-207, https://doi.org/10.5194/acp-2022-207, 2022
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.
Robert Woodward-Massey, Roberto Sommariva, Lisa K. Whalley, Danny R. Cryer, Trevor Ingham, William J. Bloss, Stephen M. Ball, 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
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-213, https://doi.org/10.5194/acp-2022-213, 2022
Revised manuscript under review for ACP
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We performed a radical (OH, HO2, RO2; total ROx) budget analysis on a dataset collected during a field intensive at a UK coastal site. We found significant differences between calculated HO2 and RO2 production and destruction rates, which should be balanced for such highly reactive radicals under steady state conditions. In addition, ozone production rates were calculated from measured radicals and compared to MCMv3.3.1 model predictions.
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.
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.
Joanna E. Dyson, Graham A. Boustead, Lauren T. Fleming, Mark Blitz, Daniel Stone, Stephen R. Arnold, Lisa K. Whalley, and Dwayne E. Heard
Atmos. Chem. Phys., 21, 5755–5775, https://doi.org/10.5194/acp-21-5755-2021, https://doi.org/10.5194/acp-21-5755-2021, 2021
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The hydroxyl radical (OH) dominates the removal of atmospheric pollutants, with nitrous acid (HONO) recognised as a major OH source. For remote regions HONO production through the action of sunlight on aerosol surfaces can provide a source of nitrogen oxides. In this study, HONO production rates at illuminated aerosol surfaces are measured under atmospheric conditions, a model consistent with the data is developed and aerosol production of HONO in the atmosphere is shown to be significant.
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.
Mike J. Newland, Daniel J. Bryant, Rachel E. Dunmore, Thomas J. Bannan, W. Joe F. Acton, Ben Langford, James R. Hopkins, Freya A. Squires, William Dixon, William S. Drysdale, Peter D. Ivatt, Mathew J. Evans, Peter M. Edwards, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, C. Nicholas Hewitt, James D. Lee, Tianqu Cui, Jason D. Surratt, Xinming Wang, Alastair C. Lewis, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 21, 1613–1625, https://doi.org/10.5194/acp-21-1613-2021, https://doi.org/10.5194/acp-21-1613-2021, 2021
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We report the formation of secondary pollutants in the urban megacity of Beijing that are typically associated with remote regions such as rainforests. This is caused by extremely low levels of nitric oxide (NO), typically expected to be high in urban areas, observed in the afternoon. This work has significant implications for how we understand atmospheric chemistry in the urban environment and thus for how to implement effective policies to improve urban air quality.
Huan Song, Xiaorui Chen, Keding Lu, Qi Zou, Zhaofeng Tan, Hendrik Fuchs, Alfred Wiedensohler, Daniel R. Moon, Dwayne E. Heard, María-Teresa Baeza-Romero, Mei Zheng, Andreas Wahner, Astrid Kiendler-Scharr, and Yuanhang Zhang
Atmos. Chem. Phys., 20, 15835–15850, https://doi.org/10.5194/acp-20-15835-2020, https://doi.org/10.5194/acp-20-15835-2020, 2020
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Accurate calculation of the HO2 uptake coefficient is one of the key parameters to quantify the co-reduction of both aerosol and ozone pollution. We modelled various lab measurements of γHO2 based on a gas-liquid phase kinetic model and developed a state-of-the-art parameterized equation. Based on a dataset from a comprehensive field campaign in the North China Plain, we proposed that the determination of the heterogeneous uptake process for HO2 should be included in future field campaigns.
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.
Daniel J. Bryant, William J. Dixon, James R. Hopkins, Rachel E. Dunmore, Kelly L. Pereira, Marvin Shaw, Freya A. Squires, Thomas J. Bannan, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Bin Ouyang, Tianqu Cui, Jason D. Surratt, Di Liu, Zongbo Shi, Roy Harrison, Yele Sun, Weiqi Xu, Alastair C. Lewis, James D. Lee, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 20, 7531–7552, https://doi.org/10.5194/acp-20-7531-2020, https://doi.org/10.5194/acp-20-7531-2020, 2020
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Using the chemical composition of offline filter samples, we report that a large share of oxidized organic aerosol in Beijing during summer is due to isoprene secondary organic aerosol (iSOA). iSOA organosulfates showed a strong correlation with the product of ozone and particulate sulfate. This highlights the role of both photochemistry and the availability of particulate sulfate in heterogeneous reactions and further demonstrates that iSOA formation is controlled by anthropogenic emissions.
Robert Woodward-Massey, Eloise J. Slater, Jake Alen, Trevor Ingham, Danny R. Cryer, Leanne M. Stimpson, Chunxiang Ye, Paul W. Seakins, Lisa K. Whalley, and Dwayne E. Heard
Atmos. Meas. Tech., 13, 3119–3146, https://doi.org/10.5194/amt-13-3119-2020, https://doi.org/10.5194/amt-13-3119-2020, 2020
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The OH radical is known as nature’s detergent, removing most trace gases from the atmosphere. Hence, an accurate measurement of its concentration is very important. We present measurements of OH in several field locations using a laser-based fluorescence method equipped with an OH scavenger. By determining the background signal in two different ways, we show that the instrument does not suffer any significant interferences that could result in an overestimation of OH concentrations.
Lavinia Onel, Alexander Brennan, Michele Gianella, James Hooper, Nicole Ng, Gus Hancock, Lisa Whalley, Paul W. Seakins, Grant A. D. Ritchie, and Dwayne E. Heard
Atmos. Meas. Tech., 13, 2441–2456, https://doi.org/10.5194/amt-13-2441-2020, https://doi.org/10.5194/amt-13-2441-2020, 2020
Michael Hollaway, Oliver Wild, Ting Yang, Yele Sun, Weiqi Xu, Conghui Xie, Lisa Whalley, Eloise Slater, Dwayne Heard, and Dantong Liu
Atmos. Chem. Phys., 19, 9699–9714, https://doi.org/10.5194/acp-19-9699-2019, https://doi.org/10.5194/acp-19-9699-2019, 2019
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This study, for the first time, uses combinations of aerosol and lidar data to drive an offline photolysis scheme. Absorbing species are shown to have the greatest impact on photolysis rate constants in the winter and scattering aerosol are shown to dominate responses in the summer. During haze episodes, aerosols are shown to produce a greater impact than cloud cover. The findings demonstrate the potential photochemical impacts of haze pollution in a highly polluted urban environment.
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.
Jacob T. Shaw, Richard T. Lidster, Danny R. Cryer, Noelia Ramirez, Fiona C. Whiting, Graham A. Boustead, Lisa K. Whalley, Trevor Ingham, Andrew R. Rickard, Rachel E. Dunmore, Dwayne E. Heard, Ally C. Lewis, Lucy J. Carpenter, Jacqui F. Hamilton, and Terry J. Dillon
Atmos. Chem. Phys., 18, 4039–4054, https://doi.org/10.5194/acp-18-4039-2018, https://doi.org/10.5194/acp-18-4039-2018, 2018
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The lifetime of a chemical in the atmosphere is largely governed by the rate of its reaction with the hydroxyl radical (OH). Measurements of rates for many of the thousands of identified volatile organic compounds (VOCs) have yet to be determined experimentally. We have developed a new technique for the rapid determination of gas-phase rate coefficients for the simultaneous reactions between multiple VOCs and OH. The method is tasted across a range of scenarios and is used to derive new values.
Daniel Stone, Tomás Sherwen, Mathew J. Evans, Stewart Vaughan, Trevor Ingham, Lisa K. Whalley, Peter M. Edwards, Katie A. Read, James D. Lee, Sarah J. Moller, Lucy J. Carpenter, Alastair C. Lewis, and Dwayne E. Heard
Atmos. Chem. Phys., 18, 3541–3561, https://doi.org/10.5194/acp-18-3541-2018, https://doi.org/10.5194/acp-18-3541-2018, 2018
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Halogen chemistry in the troposphere impacts oxidising capacity, but model studies assessing the nature of these impacts can vary according to the model framework used. In this work we present simulations of OH and HO2 radicals using both box and global model frameworks, and compare to observations made at the Cape Verde Atmospheric Observatory. We highlight, and rationalise, differences between the model frameworks.
Lisa K. Whalley, Daniel Stone, Rachel Dunmore, Jacqueline Hamilton, James R. Hopkins, James D. Lee, Alastair C. Lewis, Paul Williams, Jörg Kleffmann, Sebastian Laufs, Robert Woodward-Massey, and Dwayne E. Heard
Atmos. Chem. Phys., 18, 2547–2571, https://doi.org/10.5194/acp-18-2547-2018, https://doi.org/10.5194/acp-18-2547-2018, 2018
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This paper presents the first radical observations made in London and subsequent model comparisons. This work highlights that there are uncertainties in the degradation mechanism of complex biogenic and diesel-related VOC species under low-NOx conditions and under high-NOx conditions there is a missing source of RO2 radicals. The impact of these model uncertainties on in situ ozone production as a function of NOx is discussed.
Daniel R. Moon, Giorgio S. Taverna, Clara Anduix-Canto, Trevor Ingham, Martyn P. Chipperfield, Paul W. Seakins, Maria-Teresa Baeza-Romero, and Dwayne E. Heard
Atmos. Chem. Phys., 18, 327–338, https://doi.org/10.5194/acp-18-327-2018, https://doi.org/10.5194/acp-18-327-2018, 2018
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One geoengineering mitigation strategy for global temperature rises is to inject particles into the stratosphere to scatter solar radiation back to space. However, the injection of such particles must not perturb ozone. We measured the rate of uptake of HO2 radicals, an important stratospheric intermediate, onto TiO2 particles. Using the atmospheric model TOMCAT, we showed that surface reactions between HO2 and TiO2 would have a negligible effect on stratospheric concentrations of HO2 and ozone.
Lavinia Onel, Alexander Brennan, Michele Gianella, Grace Ronnie, Ana Lawry Aguila, Gus Hancock, Lisa Whalley, Paul W. Seakins, Grant A. D. Ritchie, and Dwayne E. Heard
Atmos. Meas. Tech., 10, 4877–4894, https://doi.org/10.5194/amt-10-4877-2017, https://doi.org/10.5194/amt-10-4877-2017, 2017
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Hydroperoxy (HO2) radicals are key intermediates participating in a rapid chemical cycling at the centre of the tropospheric oxidation. Fluorescence assay by gas expansion (FAGE) technique is the most commonly used for the HO2 measurements in the atmosphere. However, FAGE is an indirect technique, requiring calibration. This work finds a good agreement between the indirect FAGE method and the direct cavity ring-down spectroscopy method and hence validates FAGE and the FAGE calibration method.
Lavinia Onel, Alexander Brennan, Paul W. Seakins, Lisa Whalley, and Dwayne E. Heard
Atmos. Meas. Tech., 10, 3985–4000, https://doi.org/10.5194/amt-10-3985-2017, https://doi.org/10.5194/amt-10-3985-2017, 2017
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Methyl peroxy (CH3O2) radicals are the most abundant organic peroxy radical species and are critical intermediates in rapid chemical cycling at the heart of tropospheric oxidation. Despite their importance, at present CH3O2 radicals are not specifically measured in the atmosphere by any direct or indirect method. This work presents a new method for the selective and sensitive detection of CH3O2 radicals and its use for the measurement of CH3O2 in the atmospheric simulation chamber HIRAC.
Hendrik Fuchs, Anna Novelli, Michael Rolletter, Andreas Hofzumahaus, Eva Y. Pfannerstill, Stephan Kessel, Achim Edtbauer, Jonathan Williams, Vincent Michoud, Sebastien Dusanter, Nadine Locoge, Nora Zannoni, Valerie Gros, Francois Truong, Roland Sarda-Esteve, Danny R. Cryer, Charlotte A. Brumby, Lisa K. Whalley, Daniel Stone, Paul W. Seakins, Dwayne E. Heard, Coralie Schoemaecker, Marion Blocquet, Sebastien Coudert, Sebastien Batut, Christa Fittschen, Alexander B. Thames, William H. Brune, Cheryl Ernest, Hartwig Harder, Jennifer B. A. Muller, Thomas Elste, Dagmar Kubistin, Stefanie Andres, Birger Bohn, Thorsten Hohaus, Frank Holland, Xin Li, Franz Rohrer, Astrid Kiendler-Scharr, Ralf Tillmann, Robert Wegener, Zhujun Yu, Qi Zou, and Andreas Wahner
Atmos. Meas. Tech., 10, 4023–4053, https://doi.org/10.5194/amt-10-4023-2017, https://doi.org/10.5194/amt-10-4023-2017, 2017
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Hydroxyl radical reactivity (k(OH)) is closely related to processes that lead to the formation of oxidised, secondary pollutants such as ozone and aerosol. In order to compare the performances of instruments measuring k(OH), experiments were conducted in the simulation chamber SAPHIR. Chemical conditions were chosen either to be representative of the atmosphere or to test potential limitations of instruments. Overall, the results show that instruments are capable of measuring k(OH).
Pascale S. J. Lakey, Thomas Berkemeier, Manuel Krapf, Josef Dommen, Sarah S. Steimer, Lisa K. Whalley, Trevor Ingham, Maria T. Baeza-Romero, Ulrich Pöschl, Manabu Shiraiwa, Markus Ammann, and Dwayne E. Heard
Atmos. Chem. Phys., 16, 13035–13047, https://doi.org/10.5194/acp-16-13035-2016, https://doi.org/10.5194/acp-16-13035-2016, 2016
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Chemical oxidation in the atmosphere removes pollutants and greenhouse gases but generates undesirable products such as secondary organic aerosol. Radicals are key intermediates in oxidation, but how they interact with aerosols is still not well understood. Here we use a laser to measure the loss of radicals onto oxidised aerosols generated in a smog chamber. The loss of radicals was controlled by the thickness or viscosity of the aerosols, confirmed by using sugar aerosols of known thickness.
Óscar Gálvez, M. Teresa Baeza-Romero, Mikel Sanz, and Alfonso Saiz-Lopez
Atmos. Chem. Phys., 16, 12703–12713, https://doi.org/10.5194/acp-16-12703-2016, https://doi.org/10.5194/acp-16-12703-2016, 2016
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Reactive iodine species play a key role in the oxidation capacity of the polar troposphere, although sources and mechanisms are poorly understood. In this paper, the photolysis of frozen iodate salt has been studied, confirming that under near-UV–Vis radiation iodate is photolysed. Incorporating this result into an Antarctic atmospheric model, we have shown that it could increase the atmospheric IO levels and could constitute a pathway for the release of active iodine to the polar atmosphere
Birger Bohn, Dwayne E. Heard, Nikolaos Mihalopoulos, Christian Plass-Dülmer, Rainer Schmitt, and Lisa K. Whalley
Atmos. Meas. Tech., 9, 3455–3466, https://doi.org/10.5194/amt-9-3455-2016, https://doi.org/10.5194/amt-9-3455-2016, 2016
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Filter radiometers are instruments that quantify the rate of formation of excited oxygen atoms from photolysis of ozone in the atmosphere. The excited oxygen atoms are important for the atmospheric self-cleaning ability. The radiometers were characterised by measurements of their spectral response. Together with field comparisons with a reference instrument, the characterisations improved the performance. That will help to better understand atmospheric photochemistry in future research.
Daniel Stone, Lisa K. Whalley, Trevor Ingham, Peter M. Edwards, Danny R. Cryer, Charlotte A. Brumby, Paul W. Seakins, and Dwayne E. Heard
Atmos. Meas. Tech., 9, 2827–2844, https://doi.org/10.5194/amt-9-2827-2016, https://doi.org/10.5194/amt-9-2827-2016, 2016
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OH reactivity is the total pseudo-first-order loss rate coefficient describing the removal of OH radicals to all sinks in the atmosphere. Measurements of ambient OH reactivity can be used to discover the extent to which measured OH sinks contribute to the total OH loss rate. In this work, we describe the design and characterisation of an instrument to measure OH reactivity using laser flash photolysis coupled to laser-induced fluorescence (LFP-LIF) spectroscopy.
Frank A. F. Winiberg, Terry J. Dillon, Stephanie C. Orr, Christoph B. M Groß, Iustinian Bejan, Charlotte A. Brumby, Matthew J. Evans, Shona C. Smith, Dwayne E. Heard, and Paul W. Seakins
Atmos. Chem. Phys., 16, 4023–4042, https://doi.org/10.5194/acp-16-4023-2016, https://doi.org/10.5194/acp-16-4023-2016, 2016
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OH radicals are important intermediates in the atmosphere, and the high concentrations observed in tropical regions are yet to be fully explained. Radical-radical reactions such as the title reaction can contribute to OH formation. This is the most fully comprehensive study of the CH3C(O)O2 + HO2 reaction with direct observation of products in all reaction channels. The implications of the new measurements on OH, PAN and NOx concentrations are considered via global models.
J. D. Lee, L. K. Whalley, D. E. Heard, D. Stone, R. E. Dunmore, J. F. Hamilton, D. E. Young, J. D. Allan, S. Laufs, and J. Kleffmann
Atmos. Chem. Phys., 16, 2747–2764, https://doi.org/10.5194/acp-16-2747-2016, https://doi.org/10.5194/acp-16-2747-2016, 2016
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This paper presents field measurements of HONO and a range of other gas phase and particulate species from an urban background site in London. The measured daytime HONO cannot be reproduced with a simple box model and thus a significant daytime missing source of HONO is present. We show that this missing source could be responsible for 40 % of the OH radical source and 57 % of the OH initiation; hence its potential importance for atmospheric oxidation and ozone production.
Lisa K. Whalley, Daniel Stone, Brian Bandy, Rachel Dunmore, Jacqueline F. Hamilton, James Hopkins, James D. Lee, Alastair C. Lewis, and Dwayne E. Heard
Atmos. Chem. Phys., 16, 2109–2122, https://doi.org/10.5194/acp-16-2109-2016, https://doi.org/10.5194/acp-16-2109-2016, 2016
H. M. Walker, D. Stone, T. Ingham, S. Vaughan, M. Cain, R. L. Jones, O. J. Kennedy, M. McLeod, B. Ouyang, J. Pyle, S. Bauguitte, B. Bandy, G. Forster, M. J. Evans, J. F. Hamilton, J. R. Hopkins, J. D. Lee, A. C. Lewis, R. T. Lidster, S. Punjabi, W. T. Morgan, and D. E. Heard
Atmos. Chem. Phys., 15, 8179–8200, https://doi.org/10.5194/acp-15-8179-2015, https://doi.org/10.5194/acp-15-8179-2015, 2015
N. S. Umo, B. J. Murray, M. T. Baeza-Romero, J. M. Jones, A. R. Lea-Langton, T. L. Malkin, D. O'Sullivan, L. Neve, J. M. C. Plane, and A. Williams
Atmos. Chem. Phys., 15, 5195–5210, https://doi.org/10.5194/acp-15-5195-2015, https://doi.org/10.5194/acp-15-5195-2015, 2015
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Combustion ash particles nucleate ice in the immersion mode at conditions relevant to mixed-phase clouds. Hence, combustion ashes could play an important role in primary ice formation in mixed-phase clouds, especially in clouds that are formed near the emission source of these aerosol particles. From this study, there is a need to quantify the atmospheric abundance of combustion ashes in order to quantitatively assess the impact of combustion ashes on mixed-phase clouds.
L. K. Whalley, D. Stone, I. J. George, S. Mertes, D. van Pinxteren, A. Tilgner, H. Herrmann, M. J. Evans, and D. E. Heard
Atmos. Chem. Phys., 15, 3289–3301, https://doi.org/10.5194/acp-15-3289-2015, https://doi.org/10.5194/acp-15-3289-2015, 2015
F. A. F. Winiberg, S. C. Smith, I. Bejan, C. A. Brumby, T. Ingham, T. L. Malkin, S. C. Orr, D. E. Heard, and P. W. Seakins
Atmos. Meas. Tech., 8, 523–540, https://doi.org/10.5194/amt-8-523-2015, https://doi.org/10.5194/amt-8-523-2015, 2015
D. Stone, M. J. Evans, H. Walker, T. Ingham, S. Vaughan, B. Ouyang, O. J. Kennedy, M. W. McLeod, R. L. Jones, J. Hopkins, S. Punjabi, R. Lidster, J. F. Hamilton, J. D. Lee, A. C. Lewis, L. J. Carpenter, G. Forster, D. E. Oram, C. E. Reeves, S. Bauguitte, W. Morgan, H. Coe, E. Aruffo, C. Dari-Salisburgo, F. Giammaria, P. Di Carlo, and D. E. Heard
Atmos. Chem. Phys., 14, 1299–1321, https://doi.org/10.5194/acp-14-1299-2014, https://doi.org/10.5194/acp-14-1299-2014, 2014
X. Pang, A. C. Lewis, A. R. Rickard, M. T. Baeza-Romero, T. J. Adams, S. M. Ball, M. J. S. Daniels, I. C. A. Goodall, P. S. Monks, S. Peppe, M. Ródenas García, P. Sánchez, and A. Muñoz
Atmos. Meas. Tech., 7, 373–389, https://doi.org/10.5194/amt-7-373-2014, https://doi.org/10.5194/amt-7-373-2014, 2014
L. K. Whalley, M. A. Blitz, M. Desservettaz, P. W. Seakins, and D. E. Heard
Atmos. Meas. Tech., 6, 3425–3440, https://doi.org/10.5194/amt-6-3425-2013, https://doi.org/10.5194/amt-6-3425-2013, 2013
P. M. Edwards, M. J. Evans, K. L. Furneaux, J. Hopkins, T. Ingham, C. Jones, J. D. Lee, A. C. Lewis, S. J. Moller, D. Stone, L. K. Whalley, and D. E. Heard
Atmos. Chem. Phys., 13, 9497–9514, https://doi.org/10.5194/acp-13-9497-2013, https://doi.org/10.5194/acp-13-9497-2013, 2013
N. J. Warwick, A. T. Archibald, K. Ashworth, J. Dorsey, P. M. Edwards, D. E. Heard, B. Langford, J. Lee, P. K. Misztal, L. K. Whalley, and J. A. Pyle
Atmos. Chem. Phys., 13, 9183–9194, https://doi.org/10.5194/acp-13-9183-2013, https://doi.org/10.5194/acp-13-9183-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Laboratory Studies | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Photo-induced shrinking of aqueous glycine aerosol droplets
Sulfate formation via aerosol-phase SO2 oxidation by model biomass burning photosensitizers: 3,4-dimethoxybenzaldehyde, vanillin and syringaldehyde using single-particle mixing-state analysis
Yields and molecular composition of gas-phase and secondary organic aerosol from the photooxidation of the volatile consumer product benzyl alcohol: formation of highly oxygenated and hydroxy nitro-aromatic compounds
A combined gas- and particle-phase analysis of highly oxygenated organic molecules (HOMs) from α-pinene ozonolysis
Comparison of aqueous secondary organic aerosol (aqSOA) product distributions from guaiacol oxidation by non-phenolic and phenolic methoxybenzaldehydes as photosensitizers in the absence and presence of ammonium nitrate
Technical note: Chemical composition and source identification of fluorescent components in atmospheric water-soluble brown carbon by excitation–emission matrix spectroscopy with parallel factor analysis – potential limitations and applications
Insoluble lipid film mediates transfer of soluble saccharides from the sea to the atmosphere: the role of hydrogen bonding
Simultaneous Formation of Sulfate and Nitrate via Co-uptake of SO2 and NO2 by Aqueous NaCl Droplets: Combined Effect of Nitrate Photolysis and Chlorine Chemistry
Magnetic fraction of the atmospheric dust in Kraków – physicochemical characteristics and possible environmental impact
Modeling daytime and nighttime secondary organic aerosol formation via multiphase reactions of biogenic hydrocarbons
SO2 enhances aerosol formation from anthropogenic volatile organic compound ozonolysis by producing sulfur-containing compounds
Isothermal evaporation of α-pinene secondary organic aerosol particles formed under low NOx and high NOx conditions
Chemical characterization of organic compounds involved in iodine-initiated new particle formation from coastal macroalgal emission
The Urmia playa as a source of airborne dust and ice-nucleating particles – Part 2: Unraveling the relationship between soil dust composition and ice nucleation activity
Winter brown carbon over six of China's megacities: light absorption, molecular characterization, and improved source apportionment revealed by multilayer perceptron neural network
Chamber investigation of the formation and transformation of secondary organic aerosol in mixtures of biogenic and anthropogenic volatile organic compounds
Not all types of secondary organic aerosol mix: two phases observed when mixing different secondary organic aerosol types
Comprehensive characterization of particulate intermediate-volatility and semi-volatile organic compounds (I/SVOCs) from heavy-duty diesel vehicles using two-dimensional gas chromatography time-of-flight mass spectrometry
Measurement report: Investigation of pH- and particle-size-dependent chemical and optical properties of water-soluble organic carbon: implications for its sources and aging processes
The influence of the addition of isoprene on the volatility of particles formed from the photo-oxidation of anthropogenic–biogenic mixtures
Significant formation of sulfate aerosols contributed by the heterogeneous drivers of dust surface
Chemical evolution of primary and secondary biomass burning aerosols during daytime and nighttime
Particle-phase processing of α-pinene NO3 secondary organic aerosol in the dark
Chemical characteristics and sources of PM2.5 in Hohhot, a semi-arid city in northern China: insight from the COVID-19 lockdown
The positive effect of formaldehyde on the photocatalytic renoxification of nitrate on TiO2 particles
Identification of highly oxygenated organic molecules and their role in aerosol formation in the reaction of limonene with nitrate radical
A comprehensive study on hygroscopic behaviour and nitrate depletion of NaNO3 and dicarboxylic acid mixtures: implications for nitrate depletion in tropospheric aerosols
Secondary organic aerosols from OH oxidation of cyclic volatile methyl siloxanes as an important Si source in the atmosphere
An intercomparison study of four different techniques for measuring the chemical composition of nanoparticles
Effects of OH radical and SO2 concentrations on photochemical reactions of mixed anthropogenic organic gases
Chemically distinct particle phase emissions from highly controlled pyrolysis of three wood types
Effects of the sample matrix on the photobleaching and photodegradation of toluene-derived secondary organic aerosol compounds
Functionality-based formation of secondary organic aerosol from m-xylene photooxidation
Chemical composition of secondary organic aerosol particles formed from mixtures of anthropogenic and biogenic precursors
A novel pathway of atmospheric sulfate formation through carbonate radicals
A sulfuric acid nucleation potential model for the atmosphere
Optical and chemical properties and oxidative potential of aqueous-phase products from OH and 3C∗-initiated photooxidation of eugenol
The relationship between PM2.5 and anticyclonic wave activity during summer over the United States
Iron from coal combustion particles dissolves much faster than mineral dust under simulated atmospheric acidic conditions
Cellulose in atmospheric particulate matter at rural and urban sites across France and Switzerland
Kinetics, SOA yields, and chemical composition of secondary organic aerosol from β-caryophyllene ozonolysis with and without nitrogen oxides between 213 and 313 K
Chemical transformation of α-pinene-derived organosulfate via heterogeneous OH oxidation: implications for sources and environmental fates of atmospheric organosulfates
Aqueous chemical bleaching of 4-nitrophenol brown carbon by hydroxyl radicals; products, mechanism, and light absorption
Secondary organic aerosol formation from camphene oxidation: measurements and modeling
Technical note: Real-time diagnosis of the hygroscopic growth micro-dynamics of nanoparticles with Fourier transform infrared spectroscopy
Single-particle Raman spectroscopy for studying physical and chemical processes of atmospheric particles
Are reactive oxygen species (ROS) a suitable metric to predict toxicity of carbonaceous aerosol particles?
Secondary organic aerosol and organic nitrogen yields from the nitrate radical (NO3) oxidation of alpha-pinene from various RO2 fates
Secondary organic aerosol formation from the oxidation of decamethylcyclopentasiloxane at atmospherically relevant OH concentrations
Aqueous secondary organic aerosol formation from the direct photosensitized oxidation of vanillin in the absence and presence of ammonium nitrate
Shinnosuke Ishizuka, Oliver Reich, Grégory David, and Ruth Signorell
Atmos. Chem. Phys., 23, 5393–5402, https://doi.org/10.5194/acp-23-5393-2023, https://doi.org/10.5194/acp-23-5393-2023, 2023
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Photosensitizers play an important role in the photochemistry of atmospheric aerosols. Our study provides evidence that mesoscopic glycine clusters forming in aqueous droplets act as unconventional photosensitizers in the visible light spectrum. We observed the influence of these photoactive molecular aggregates in single optically trapped aqueous droplets. Such mesoscopic photosensitizers might be more important for aerosol photochemistry than previously anticipated.
Liyuan Zhou, Zhancong Liang, Beatrix Rosette Go Mabato, Rosemarie Ann Infante Cuevas, Rongzhi Tang, Mei Li, Chunlei Cheng, and Chak K. Chan
Atmos. Chem. Phys., 23, 5251–5261, https://doi.org/10.5194/acp-23-5251-2023, https://doi.org/10.5194/acp-23-5251-2023, 2023
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This study reveals the sulfate formation in photosensitized particles from biomass burning under UV and SO2, of which the relative atmospheric importance in sulfate production was qualitatively compared to nitrate photolysis. On the basis of single-particle aerosol mass spectrometry measurements, the number percentage of sulfate-containing particles and relative peak area of sulfate in single-particle spectra exhibited a descending order of 3,4-dimethoxybenzaldehyde > vanillin > syringaldehyde.
Mohammed Jaoui, Kenneth S. Docherty, Michael Lewandowski, and Tadeusz E. Kleindienst
Atmos. Chem. Phys., 23, 4637–4661, https://doi.org/10.5194/acp-23-4637-2023, https://doi.org/10.5194/acp-23-4637-2023, 2023
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VCPs are a class of chemicals widely used in industrial and consumer products (e.g., coatings, adhesives, inks, personal care products) and are an important component of total VOCs in urban atmospheres. This study provides SOA yields and detailed chemical analysis of the gas- and aerosol-phase products of the photooxidation of one of these VCPs, benzyl alcohol. These results will allow better links between characterized sources and their resulting criteria for pollutant formation.
Jian Zhao, Ella Häkkinen, Frans Graeffe, Jordan E. Krechmer, Manjula R. Canagaratna, Douglas R. Worsnop, Juha Kangasluoma, and Mikael Ehn
Atmos. Chem. Phys., 23, 3707–3730, https://doi.org/10.5194/acp-23-3707-2023, https://doi.org/10.5194/acp-23-3707-2023, 2023
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Based on the combined measurements of gas- and particle-phase highly oxygenated organic molecules (HOMs) from α-pinene ozonolysis, enhancement of dimers in particles was observed. We conducted experiments wherein the dimer to monomer (D / M) ratios of HOMs in the gas phase were modified (adding CO / NO) to investigate the effects of the corresponding D / M ratios in the particles. These results are important for a better understanding of secondary organic aerosol formation in the atmosphere.
Beatrix Rosette Go Mabato, Yong Jie Li, Dan Dan Huang, Yalin Wang, and Chak K. Chan
Atmos. Chem. Phys., 23, 2859–2875, https://doi.org/10.5194/acp-23-2859-2023, https://doi.org/10.5194/acp-23-2859-2023, 2023
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We compared non-phenolic and phenolic methoxybenzaldehydes as photosensitizers for aqueous secondary organic aerosol (aqSOA) formation under cloud and fog conditions. We showed that the structural features of photosensitizers affect aqSOA formation. We also elucidated potential interactions between photosensitization and ammonium nitrate photolysis. Our findings are useful for evaluating the importance of photosensitized reactions on aqSOA formation, which could improve aqSOA predictive models.
Tao Cao, Meiju Li, Cuncun Xu, Jianzhong Song, Xingjun Fan, Jun Li, Wanglu Jia, and Ping'an Peng
Atmos. Chem. Phys., 23, 2613–2625, https://doi.org/10.5194/acp-23-2613-2023, https://doi.org/10.5194/acp-23-2613-2023, 2023
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This work comprehensively investigated the fluorescence data of light-absorbing organic compounds, water-soluble organic matter in different types of aerosol samples, soil dust, and fulvic and humic acids using an excitation–emission matrix (EEM) method and parallel factor modeling. The results revealed which light-absorbing species can be detected by EEM and also provided important information for identifying the chemical composition and possible sources of these species in atmospheric samples.
Minglan Xu, Narcisse Tsona Tchinda, Jianlong Li, and Lin Du
Atmos. Chem. Phys., 23, 2235–2249, https://doi.org/10.5194/acp-23-2235-2023, https://doi.org/10.5194/acp-23-2235-2023, 2023
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The promotion of soluble saccharides on sea spray aerosol (SSA) generation and the changes in particle morphology were observed. On the contrary, the coexistence of surface insoluble fatty acid film and soluble saccharides significantly inhibited the production of SSA. This is the first demonstration that hydrogen bonding mediated by surface-insoluble fatty acids contributes to saccharide transfer in seawater, providing a new mechanism for saccharide enrichment in SSA.
Ruifeng Zhang and Chak Keung Chan
EGUsphere, https://doi.org/10.5194/egusphere-2023-223, https://doi.org/10.5194/egusphere-2023-223, 2023
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Research in sulfate and nitrate formation from co-uptake of NO2 and SO2, especially under irradiation, is rare. We studied the co-uptake of NO2 and SO2 by NaCl droplets under various conditions, including irradiation/dark and different RHs, using Raman spectroscopy/Flow cell and kinetic model simulation. A significant nitrate from NO2 hydrolysis can be photolyzed to generate OH radicals that can further react with chloride to produce reactive chlorine species and promote sulfate formation.
Jan M. Michalik, Wanda Wilczyńska-Michalik, Łukasz Gondek, Waldemar Tokarz, Jan Żukrowski, Marta Gajewska, and Marek Michalik
Atmos. Chem. Phys., 23, 1449–1464, https://doi.org/10.5194/acp-23-1449-2023, https://doi.org/10.5194/acp-23-1449-2023, 2023
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The magnetic fraction of the aerosols in Kraków was collected and analysed using scanning and transmission electron microscopy with energy-dispersive spectrometry, X-ray diffraction, Mössbauer spectrometry, and magnetometry. It contains metallic Fe or Fe-rich alloy and Fe oxides. The occurrence of nanometre-scale Fe3O4 particles (predominantly of anthropogenic origin) is shown. Our results can help to determine the sources and transport of pollutants, potential harmful effects, etc.
Sanghee Han and Myoseon Jang
Atmos. Chem. Phys., 23, 1209–1226, https://doi.org/10.5194/acp-23-1209-2023, https://doi.org/10.5194/acp-23-1209-2023, 2023
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The diurnal pattern in biogenic secondary organic aerosol (SOA) formation is simulated by using the UNIPAR model, which predicts SOA growth via multiphase reactions of hydrocarbons under varying NOx levels, aerosol acidity, humidity, and temperature. The simulation suggests that nighttime SOA formation, even in urban environments, where anthropogenic emission is high, is dominated by products from ozonolysis and NO3-initiated oxidation of biogenic hydrocarbons.
Zhaomin Yang, Kun Li, Narcisse T. Tsona, Xin Luo, and Lin Du
Atmos. Chem. Phys., 23, 417–430, https://doi.org/10.5194/acp-23-417-2023, https://doi.org/10.5194/acp-23-417-2023, 2023
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SO2 significantly promotes particle formation during cyclooctene ozonolysis. Carboxylic acids and their dimers were major products in particles formed in the absence of SO2. SO2 can induce production of organosulfates with stronger particle formation ability than their precursors, leading to the enhancement in particle formation. Formation mechanisms and structures of organosulfates were proposed, which is helpful for better understanding how SO2 perturbs the formation and fate of particles.
Zijun Li, Angela Buchholz, Luis M. F. Barreira, Arttu Ylisirniö, Liqing Hao, Iida Pullinen, Siegfried Schobesberger, and Annele Virtanen
Atmos. Chem. Phys., 23, 203–220, https://doi.org/10.5194/acp-23-203-2023, https://doi.org/10.5194/acp-23-203-2023, 2023
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Interaction between NOx and biogenic emissions can be important in suburban areas. Our study showed that the addition of NOx during α-pinene SOA formation produced considerable amounts of organic nitrates and affected the composition of non-nitrated organic compounds. The compositional difference consequently altered the primary type of aqueous-phase processes during the isothermal particle evaporation.
Yibei Wan, Xiangpeng Huang, Chong Xing, Qiongqiong Wang, Xinlei Ge, and Huan Yu
Atmos. Chem. Phys., 22, 15413–15423, https://doi.org/10.5194/acp-22-15413-2022, https://doi.org/10.5194/acp-22-15413-2022, 2022
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The organic compounds involved in continental new particle formation have been investigated in depth in the last 2 decades. In contrast, no prior work has studied the exact chemical composition of organic compounds and their role in coastal new particle formation. We present a complementary study to the ongoing laboratory and field research on iodine nucleation in the coastal atmosphere. This study provided a more complete story of coastal I-NPF from low-tide macroalgal emission.
Nikou Hamzehpour, Claudia Marcolli, Kristian Klumpp, Debora Thöny, and Thomas Peter
Atmos. Chem. Phys., 22, 14931–14956, https://doi.org/10.5194/acp-22-14931-2022, https://doi.org/10.5194/acp-22-14931-2022, 2022
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Dust aerosols from dried lakebeds contain mineral particles, as well as soluble salts and (bio-)organic compounds. Here, we investigate ice nucleation (IN) activity of dust samples from Lake Urmia playa, Iran. We find high IN activity of the untreated samples that decreases after organic matter removal but increases after removing soluble salts and carbonates, evidencing inhibiting effects of soluble salts and carbonates on the IN activity of organic matter and minerals, especially microcline.
Diwei Wang, Zhenxing Shen, Qian Zhang, Yali Lei, Tian Zhang, Shasha Huang, Jian Sun, Hongmei Xu, and Junji Cao
Atmos. Chem. Phys., 22, 14893–14904, https://doi.org/10.5194/acp-22-14893-2022, https://doi.org/10.5194/acp-22-14893-2022, 2022
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The optical properties and molecular structure of atmospheric brown carbon (BrC) in winter of several megacities in China were analyzed, and the source contribution of brown carbon was improved by using positive matrix factorization coupled with a multilayer perceptron neural network. These results can provide a basis for the more effective control of BrC to reduce its impacts on regional climates and human health.
Aristeidis Voliotis, Mao Du, Yu Wang, Yunqi Shao, M. Rami Alfarra, Thomas J. Bannan, Dawei Hu, Kelly L. Pereira, Jaqueline F. Hamilton, Mattias Hallquist, Thomas F. Mentel, and Gordon McFiggans
Atmos. Chem. Phys., 22, 14147–14175, https://doi.org/10.5194/acp-22-14147-2022, https://doi.org/10.5194/acp-22-14147-2022, 2022
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Mixing experiments are crucial and highly beneficial for our understanding of atmospheric chemical interactions. However, interpretation quickly becomes complex, and both the experimental design and evaluation need to be scrutinised carefully. Advanced online and offline compositional measurements can reveal substantial additional information to aid in the interpretation of yield data, including components uniquely found in mixtures and property changes in SOA formed from mixtures of VOCs.
Fabian Mahrt, Long Peng, Julia Zaks, Yuanzhou Huang, Paul E. Ohno, Natalie R. Smith, Florence K. A. Gregson, Yiming Qin, Celia L. Faiola, Scot T. Martin, Sergey A. Nizkorodov, Markus Ammann, and Allan K. Bertram
Atmos. Chem. Phys., 22, 13783–13796, https://doi.org/10.5194/acp-22-13783-2022, https://doi.org/10.5194/acp-22-13783-2022, 2022
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The number of condensed phases in mixtures of different secondary organic aerosol (SOA) types determines their impact on air quality and climate. Here we observe the number of phases in individual particles that contain mixtures of two different types of SOA. We find that SOA mixtures can form one- or two-phase particles, depending on the difference in the average oxygen-to-carbon (O / C) ratios of the two SOA types that are internally mixed within individual particles.
Xiao He, Xuan Zheng, Shaojun Zhang, Xuan Wang, Ting Chen, Xiao Zhang, Guanghan Huang, Yihuan Cao, Liqiang He, Xubing Cao, Yuan Cheng, Shuxiao Wang, and Ye Wu
Atmos. Chem. Phys., 22, 13935–13947, https://doi.org/10.5194/acp-22-13935-2022, https://doi.org/10.5194/acp-22-13935-2022, 2022
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With the use of two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC ToF-MS), we successfully give a comprehensive characterization of particulate intermediate-volatility and semi-volatile organic compounds (I/SVOCs) emitted from heavy-duty diesel vehicles. I/SVOCs are speciated, identified, and quantified based on the patterns of the mass spectrum, and the gas–particle partitioning is fully addressed.
Yuanyuan Qin, Juanjuan Qin, Xiaobo Wang, Kang Xiao, Ting Qi, Yuwei Gao, Xueming Zhou, Shaoxuan Shi, Jingnan Li, Jingsi Gao, Ziyin Zhang, Jihua Tan, Yang Zhang, and Rongzhi Chen
Atmos. Chem. Phys., 22, 13845–13859, https://doi.org/10.5194/acp-22-13845-2022, https://doi.org/10.5194/acp-22-13845-2022, 2022
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Deep interrogation of water-soluble organic carbon (WSOC) in aerosols is critical and challenging considering its involvement in many key aerosol-associated chemical reactions. This work examined how the chemical structures (functional groups) and optical properties (UV/fluorescence properties) of WSOC were affected by pH and particle size. We found that the pH- and particle-size-dependent behaviors could be used to reveal the structures, sources, and aging of aerosol WSOC.
Aristeidis Voliotis, Mao Du, Yu Wang, Yunqi Shao, Thomas J. Bannan, Michael Flynn, Spyros N. Pandis, Carl J. Percival, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 13677–13693, https://doi.org/10.5194/acp-22-13677-2022, https://doi.org/10.5194/acp-22-13677-2022, 2022
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The addition of a low-yield precursor to the reactive mixture of aVOC and bVOC can increase or decrease the SOA volatility that is system-dependent. Therefore, the SOA volatility of the mixtures cannot always be predicted based on the additivity. In complex mixtures the formation of lower-volatility products likely outweighs the formation of products with higher volatility. The unique products of each mixture contribute significantly to the signal, suggesting interactions can be important.
Tao Wang, Yangyang Liu, Hanyun Cheng, Zhenzhen Wang, Hongbo Fu, Jianmin Chen, and Liwu Zhang
Atmos. Chem. Phys., 22, 13467–13493, https://doi.org/10.5194/acp-22-13467-2022, https://doi.org/10.5194/acp-22-13467-2022, 2022
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This study compared the gas-phase, aqueous-phase, and heterogeneous SO2 oxidation pathways by combining laboratory work with a modelling study. The heterogeneous oxidation, particularly that induced by the dust surface drivers, presents positive implications for the removal of airborne SO2 and formation of sulfate aerosols. This work highlighted the atmospheric significance of heterogeneous oxidation and suggested a comparison model to evaluate the following heterogeneous laboratory research.
Amir Yazdani, Satoshi Takahama, John K. Kodros, Marco Paglione, Mauro Masiol, Stefania Squizzato, Kalliopi Florou, Christos Kaltsonoudis, Spiro D. Jorga, Spyros N. Pandis, and Athanasios Nenes
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-658, https://doi.org/10.5194/acp-2022-658, 2022
Revised manuscript accepted for ACP
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Organic aerosols directly emitted from wood and pellet stove combustion are found to chemically transform (approximately 15–35 % by mass) under daytime aging conditions simulated in an environmental chamber. A new marker for lignin-like compounds is found to degrade at a different rate than previously identified biomass burning markers and can potentially provide indication of aging time in ambient samples.
David M. Bell, Cheng Wu, Amelie Bertrand, Emelie Graham, Janne Schoonbaert, Stamatios Giannoukos, Urs Baltensperger, Andre S. H. Prevot, Ilona Riipinen, Imad El Haddad, and Claudia Mohr
Atmos. Chem. Phys., 22, 13167–13182, https://doi.org/10.5194/acp-22-13167-2022, https://doi.org/10.5194/acp-22-13167-2022, 2022
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A series of studies designed to investigate the evolution of organic aerosol were performed in an atmospheric simulation chamber, using a common oxidant found at night (NO3). The chemical composition steadily changed from its initial composition via different chemical reactions that were taking place inside of the aerosol particle. These results show that the composition of organic aerosol steadily changes during its lifetime in the atmosphere.
Haijun Zhou, Tao Liu, Bing Sun, Yongli Tian, Xingjun Zhou, Feng Hao, Xi Chun, Zhiqiang Wan, Peng Liu, Jingwen Wang, and Dagula Du
Atmos. Chem. Phys., 22, 12153–12166, https://doi.org/10.5194/acp-22-12153-2022, https://doi.org/10.5194/acp-22-12153-2022, 2022
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A single year’s offline measurement was conducted in Hohhot to reveal the chemical characteristics and sources of PM2.5 in a semi-arid region. We believe that our study makes a significant contribution to the literature because relatively few studies have focused on the chemical composition and sources of PM2.5 with offline measurements. A knowledge gap exists concerning how chemical composition and sources respond to implemented control measures for aerosols, particularly in a semi-arid region.
Yuhan Liu, Xuejiao Wang, Jing Shang, Weiwei Xu, Mengshuang Sheng, and Chunxiang Ye
Atmos. Chem. Phys., 22, 11347–11358, https://doi.org/10.5194/acp-22-11347-2022, https://doi.org/10.5194/acp-22-11347-2022, 2022
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In this study, the influence of HCHO on renoxification on nitrate-doped TiO2 particles is investigated by using an experimental chamber. Mass NOx release is suggested to follow the NO−3-NO3·-HNO3-NOx pathway, with HCHO involved in the transformation of NO3· to HNO3 through hydrogen abstraction. Our proposed reaction mechanism by which HCHO promotes photocatalytic renoxification is helpful for deeply understanding the atmospheric photochemical processes and nitrogen cycling.
Yindong Guo, Hongru Shen, Iida Pullinen, Hao Luo, Sungah Kang, Luc Vereecken, Hendrik Fuchs, Mattias Hallquist, Ismail-Hakki Acir, Ralf Tillmann, Franz Rohrer, Jürgen Wildt, Astrid Kiendler-Scharr, Andreas Wahner, Defeng Zhao, and Thomas F. Mentel
Atmos. Chem. Phys., 22, 11323–11346, https://doi.org/10.5194/acp-22-11323-2022, https://doi.org/10.5194/acp-22-11323-2022, 2022
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The oxidation of limonene, a common volatile emitted by trees and chemical products, by NO3, a nighttime oxidant, forms many highly oxygenated organic molecules (HOM), including C10-30 compounds. Most of the HOM are second-generation organic nitrates, in which carbonyl-substituted C10 nitrates accounted for a major fraction. Their formation can be explained by chemistry of peroxy radicals. HOM, especially low-volatile ones, play an important role in nighttime new particle formation and growth.
Shuaishuai Ma, Qiong Li, and Yunhong Zhang
Atmos. Chem. Phys., 22, 10955–10970, https://doi.org/10.5194/acp-22-10955-2022, https://doi.org/10.5194/acp-22-10955-2022, 2022
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The nitrate phase state can play a critical role in determining the occurrence and extent of nitrate depletion in internally mixed NaNO3–DCA particles, which may be instructive for relevant aerosol reaction systems. Besides, organic acids have a potential to deplete nitrate based on the comprehensive consideration of acidity, particle-phase state, droplet water activity, and HNO3 gas-phase diffusion.
Chong Han, Hongxing Yang, Kun Li, Patrick Lee, John Liggio, Amy Leithead, and Shao-Meng Li
Atmos. Chem. Phys., 22, 10827–10839, https://doi.org/10.5194/acp-22-10827-2022, https://doi.org/10.5194/acp-22-10827-2022, 2022
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We presented yields and compositions of Si-containing SOAs generated from the reaction of cVMSs (D3–D6) with OH radicals. NOx played a negative role in cVMS SOA formation, while ammonium sulfate seeds enhanced D3–D5 SOA yields at short photochemical ages under high-NOx conditions. The aerosol mass spectra confirmed that the components of cVMS SOAs significantly relied on OH exposure. A global cVMS-derived SOA source strength was estimated in order to understand SOA formation potentials of cVMSs.
Lucía Caudillo, Mihnea Surdu, Brandon Lopez, Mingyi Wang, Markus Thoma, Steffen Bräkling, Angela Buchholz, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Martin Heinritzi, Antonio Amorim, David M. Bell, Zoé Brasseur, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Xu-Cheng He, Houssni Lamkaddam, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Roy L. Mauldin, Bernhard Mentler, Antti Onnela, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Wiebke Scholz, Jiali Shen, Dominik Stolzenburg, Christian Tauber, Ping Tian, António Tomé, Nsikanabasi Silas Umo, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, André Welti, Marcel Zauner-Wieczorek, Urs Baltensperger, Richard C. Flagan, Armin Hansel, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Douglas R. Worsnop, Imad El Haddad, Neil M. Donahue, Alexander L. Vogel, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-498, https://doi.org/10.5194/acp-2022-498, 2022
Revised manuscript accepted for ACP
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In this study, we present an intercomparison study of four different techniques for measuring the chemical composition of nanoparticles. The intercomparison was performed based on the observed chemical composition, calculated volatility, and analysis of the thermograms. We found that the methods generally agree on the most important compounds that are found in the nanoparticles. However, they do see different parts of the organic spectrum. We suggest potential explanations for these differences.
Junling Li, Kun Li, Hao Zhang, Xin Zhang, Yuanyuan Ji, Wanghui Chu, Yuxue Kong, Yangxi Chu, Yanqin Ren, Yujie Zhang, Haijie Zhang, Rui Gao, Zhenhai Wu, Fang Bi, Xuan Chen, Xuezhong Wang, Weigang Wang, Hong Li, and Maofa Ge
Atmos. Chem. Phys., 22, 10489–10504, https://doi.org/10.5194/acp-22-10489-2022, https://doi.org/10.5194/acp-22-10489-2022, 2022
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Ozone formation is enhanced by higher OH concentration and higher temperature but is influenced little by SO2. SO2 can largely enhance the particle formation. Organo-sulfates and organo-nitrates are detected in the formed particles, and the presence of SO2 can promote the formation of organo-sulfates. The results provide a scientific basis for systematically evaluating the effects of SO2, OH concentration, and temperature on the oxidation of mixed organic gases in the atmosphere.
Anita M. Avery, Mariam Fawaz, Leah R. Williams, Tami Bond, and Timothy B. Onasch
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-535, https://doi.org/10.5194/acp-2022-535, 2022
Revised manuscript accepted for ACP
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Pyrolysis is the thermal decomposition of fuels like wood, which occurs during combustion or as an isolated process. During combustion, some pyrolysis products are emitted directly, while others are oxidized in the combustion process. This work describes the chemical composition of particle-phase pyrolysis products in order to inform both the uncombusted emissions from wild fires, and the fuel that participates in combustion.
Alexandra L. Klodt, Marley Adamek, Monica Dibley, Sergey A. Nizkorodov, and Rachel E. O'Brien
Atmos. Chem. Phys., 22, 10155–10171, https://doi.org/10.5194/acp-22-10155-2022, https://doi.org/10.5194/acp-22-10155-2022, 2022
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We investigated photochemistry of a secondary organic aerosol under three different conditions: in a dilute aqueous solution mimicking cloud droplets, in a solution of concentrated ammonium sulfate mimicking deliquesced aerosol, and in an organic matrix mimicking dry organic aerosol. We find that rate and mechanisms of photochemistry depend sensitively on these conditions, suggesting that the same organic aerosol compounds will degrade at different rates depending on their local environment.
Yixin Li, Jiayun Zhao, Mario Gomez-Hernandez, Michael Lavallee, Natalie M. Johnson, and Renyi Zhang
Atmos. Chem. Phys., 22, 9843–9857, https://doi.org/10.5194/acp-22-9843-2022, https://doi.org/10.5194/acp-22-9843-2022, 2022
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Here we elucidate the production of COOs and their roles in SOA and brown carbon formation from m-xylene oxidation by simultaneously monitoring the evolution of gas-phase products and aerosol properties in an environmental chamber. A kinetic framework is developed to predict SOA production from the concentrations and uptake coefficients for COOs. This functionality-based approach reproduces SOA formation from m-xylene oxidation well and is applicable to VOC oxidation for other species.
Yunqi Shao, Aristeidis Voliotis, Mao Du, Yu Wang, Kelly Pereira, Jacqueline Hamilton, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 9799–9826, https://doi.org/10.5194/acp-22-9799-2022, https://doi.org/10.5194/acp-22-9799-2022, 2022
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This study explored the chemical properties of secondary organic aerosol (SOA) that formed from photo-oxidation of single and mixed biogenic and anthropogenic precursors. We showed that SOA chemical properties in a mixed vapour system are mainly affected by the
higher-yield precursor's oxidation products and products from
cross-product formation. This study also identifies potential tracer compounds in a mixed vapour system that might be used in SOA source attribution in future ambient studies.
Yangyang Liu, Yue Deng, Jiarong Liu, Xiaozhong Fang, Tao Wang, Kejian Li, Kedong Gong, Aziz U. Bacha, Iqra Nabi, Qiuyue Ge, Xiuhui Zhang, Christian George, and Liwu Zhang
Atmos. Chem. Phys., 22, 9175–9197, https://doi.org/10.5194/acp-22-9175-2022, https://doi.org/10.5194/acp-22-9175-2022, 2022
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Both CO2 and carbonate salt work as the precursor of carbonate radicals, which largely promotes sulfate formation during the daytime. This study provides the first indication that the carbonate radical not only plays a role as an intermediate in tropospheric anion chemistry but also as a strong oxidant for the surface processing of trace gas in the atmosphere. CO2, carbponate radicals, and sulfate receive attention from those looking at the environment, atmosphere, aerosol, and photochemistry.
Jack S. Johnson and Coty N. Jen
Atmos. Chem. Phys., 22, 8287–8297, https://doi.org/10.5194/acp-22-8287-2022, https://doi.org/10.5194/acp-22-8287-2022, 2022
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Sulfuric acid nucleation forms particles in Earth's atmosphere that influence cloud formation and climate. This study introduces the Nucleation Potential Model, which simplifies the diverse reactions between sulfuric acid and numerous precursor gases to predict nucleation rates. Results show that the model is capable of estimating the potency and concentration of mixtures of precursor gases from laboratory and field observations and can be used to model nucleation across diverse environments.
Xudong Li, Ye Tao, Longwei Zhu, Shuaishuai Ma, Shipeng Luo, Zhuzi Zhao, Ning Sun, Xinlei Ge, and Zhaolian Ye
Atmos. Chem. Phys., 22, 7793–7814, https://doi.org/10.5194/acp-22-7793-2022, https://doi.org/10.5194/acp-22-7793-2022, 2022
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This work has, for the first time, investigated the optical and chemical properties and oxidative potential of aqueous-phase photooxidation products of eugenol (a biomass-burning-emitted compound) and elucidated the interplay among these properties. Large mass yields exceeding 100 % were found, and the aqueous processing is a source of BrC (likely relevant with humic-like substances). We also show that aqueous processing can produce species that are more toxic than that of its precursor.
Ye Wang, Natalie Mahowald, Peter Hess, Wenxiu Sun, and Gang Chen
Atmos. Chem. Phys., 22, 7575–7592, https://doi.org/10.5194/acp-22-7575-2022, https://doi.org/10.5194/acp-22-7575-2022, 2022
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PM2.5 is positively related to anticyclonic wave activity (AWA) changes close to the observing sites. Changes between current and future climates in AWA can explain up to 75 % of PM2.5 variability at some stations using a linear regression model. Our analysis indicates that higher PM2.5 concentrations occur when a positive AWA anomaly is prominent, which could be critical for understanding how pollutants respond to changing atmospheric circulation and for developing robust pollution projections.
Clarissa Baldo, Akinori Ito, Michael D. Krom, Weijun Li, Tim Jones, Nick Drake, Konstantin Ignatyev, Nicholas Davidson, and Zongbo Shi
Atmos. Chem. Phys., 22, 6045–6066, https://doi.org/10.5194/acp-22-6045-2022, https://doi.org/10.5194/acp-22-6045-2022, 2022
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High ionic strength relevant to the aerosol-water enhanced proton-promoted dissolution of iron in coal fly ash (up to 7 times) but suppressed oxalate-promoted dissolution at low pH (< 3). Fe in coal fly ash dissolved up to 7 times faster than in Saharan dust at low pH. A global model with the updated dissolution rates of iron in coal fly ash suggested a larger contribution of pyrogenic dissolved Fe over regions with a strong impact from fossil fuel combustions.
Adam Brighty, Véronique Jacob, Gaëlle Uzu, Lucille Borlaza, Sébastien Conil, Christoph Hueglin, Stuart K. Grange, Olivier Favez, Cécile Trébuchon, and Jean-Luc Jaffrezo
Atmos. Chem. Phys., 22, 6021–6043, https://doi.org/10.5194/acp-22-6021-2022, https://doi.org/10.5194/acp-22-6021-2022, 2022
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With an revised analytical method and long-term sampling strategy, we have been able to elucidate much more information about atmospheric plant debris, a poorly understood class of particulate matter. We found weaker seasonal patterns at urban locations compared to rural locations and significant interannual variability in concentrations between previous years and 2020, during the COVID-19 pandemic. This suggests a possible man-made influence on plant debris concentration and source strength.
Linyu Gao, Junwei Song, Claudia Mohr, Wei Huang, Magdalena Vallon, Feng Jiang, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 22, 6001–6020, https://doi.org/10.5194/acp-22-6001-2022, https://doi.org/10.5194/acp-22-6001-2022, 2022
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We study secondary organic aerosol (SOA) from β-caryophyllene (BCP) ozonolysis with and without nitrogen oxides over 213–313 K in the simulation chamber. The yields and the rate constants were determined at 243–313 K. Chemical compositions varied at different temperatures, indicating a strong impact on the BCP ozonolysis pathways. This work helps to better understand the SOA from BCP ozonolysis for conditions representative of the real atmosphere from the boundary layer to the upper troposphere.
Rongshuang Xu, Sze In Madeleine Ng, Wing Sze Chow, Yee Ka Wong, Yuchen Wang, Donger Lai, Zhongping Yao, Pui-Kin So, Jian Zhen Yu, and Man Nin Chan
Atmos. Chem. Phys., 22, 5685–5700, https://doi.org/10.5194/acp-22-5685-2022, https://doi.org/10.5194/acp-22-5685-2022, 2022
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To date, while over a hundred organosulfates (OSs) have been detected in atmospheric aerosols, many of them are still unidentified, with unknown precursors and formation processes. We found the heterogeneous OH oxidation of an α-pinene-derived organosulfate (C10H17O5SNa, αpOS-249, αpOS-249) can proceed at an efficient rate and transform into more oxygenated OSs, which have been commonly detected in atmospheric aerosols and α-pinene-derived SOA in chamber studies.
Bartłomiej Witkowski, Priyanka Jain, and Tomasz Gierczak
Atmos. Chem. Phys., 22, 5651–5663, https://doi.org/10.5194/acp-22-5651-2022, https://doi.org/10.5194/acp-22-5651-2022, 2022
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This article describes a comprehensive investigation of the aqueous oxidation of 4-nitrophenol (4NP) by hydroxyl radicals (OH). The reaction was carried out in a laboratory photoreactor. We report the formation of key intermediates under different pH conditions and the evolution of the light absorption of the reaction solution. The results provide new insights into the formation and removal (chemical bleaching) of light-absorbing organic aerosols (atmospheric brown carbon).
Qi Li, Jia Jiang, Isaac K. Afreh, Kelley C. Barsanti, and David R. Cocker III
Atmos. Chem. Phys., 22, 3131–3147, https://doi.org/10.5194/acp-22-3131-2022, https://doi.org/10.5194/acp-22-3131-2022, 2022
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Chamber-derived secondary organic aerosol (SOA) yields from camphene are reported for the first time. The role of peroxy radicals (RO2) was investigated using chemically detailed box models. We observed higher SOA yields (up to 64 %) in the experiments with added NOx than without due to the formation of highly oxygenated organic molecules (HOMs) when
NOx is present. This work can improve the representation of camphene in air quality models and provide insights into other monoterpene studies.
Xiuli Wei, Haosheng Dai, Huaqiao Gui, Jiaoshi Zhang, Yin Cheng, Jie Wang, Yixin Yang, Youwen Sun, and Jianguo Liu
Atmos. Chem. Phys., 22, 3097–3109, https://doi.org/10.5194/acp-22-3097-2022, https://doi.org/10.5194/acp-22-3097-2022, 2022
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We demonstrated the usage of the Fourier transform infrared (FTIR) spectroscopic technique to characterize in real time the hygroscopic growth properties of nanoparticles and their phase transition micro-dynamics at the molecular level. We first realize real-time measurements of water content and dry nanoparticle mass to characterize hygroscopic growth factors. We then identify in real time the hydration interactions and the dynamic hygroscopic growth process of the functional groups.
Zhancong Liang, Yangxi Chu, Masao Gen, and Chak K. Chan
Atmos. Chem. Phys., 22, 3017–3044, https://doi.org/10.5194/acp-22-3017-2022, https://doi.org/10.5194/acp-22-3017-2022, 2022
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The properties and fate of individual airborne particles can be significantly different, leading to distinct environmental impacts (e.g., climate and human health). While many instruments only analyze an ensemble of these particles, single-particle Raman spectroscopy enables unambiguous characterization of individual particles. This paper comprehensively reviews the applications of such a technique in studying atmospheric particles, especially for their physicochemical processing.
Zhi-Hui Zhang, Elena Hartner, Battist Utinger, Benjamin Gfeller, Andreas Paul, Martin Sklorz, Hendryk Czech, Bin Xia Yang, Xin Yi Su, Gert Jakobi, Jürgen Orasche, Jürgen Schnelle-Kreis, Seongho Jeong, Thomas Gröger, Michal Pardo, Thorsten Hohaus, Thomas Adam, Astrid Kiendler-Scharr, Yinon Rudich, Ralf Zimmermann, and Markus Kalberer
Atmos. Chem. Phys., 22, 1793–1809, https://doi.org/10.5194/acp-22-1793-2022, https://doi.org/10.5194/acp-22-1793-2022, 2022
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Using a novel setup, we comprehensively characterized the formation of particle-bound reactive oxygen species (ROS) in anthropogenic and biogenic secondary organic aerosols (SOAs). We found that more than 90 % of all ROS components in both SOA types have a short lifetime. Our results also show that photochemical aging promotes particle-bound ROS production and enhances the oxidative potential of the aerosols. We found consistent results between chemical-based and biological-based ROS analyses.
Kelvin H. Bates, Guy J. P. Burke, James D. Cope, and Tran B. Nguyen
Atmos. Chem. Phys., 22, 1467–1482, https://doi.org/10.5194/acp-22-1467-2022, https://doi.org/10.5194/acp-22-1467-2022, 2022
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The main nighttime sink of α-pinene, a hydrocarbon abundantly emitted by plants, is reaction with NO3 to form nitrooxy peroxy radicals (nRO2). Using uniquely designed chamber experiments, we show that this reaction is a major source of organic aerosol when nRO2 reacts with other nRO2 and forms a nitrooxy hydroperoxide when nRO2 reacts with HO2. Under ambient conditions these pathways are key loss processes of atmospheric reactive nitrogen in areas with mixed biogenic and anthropogenic influence.
Sophia M. Charan, Yuanlong Huang, Reina S. Buenconsejo, Qi Li, David R. Cocker III, and John H. Seinfeld
Atmos. Chem. Phys., 22, 917–928, https://doi.org/10.5194/acp-22-917-2022, https://doi.org/10.5194/acp-22-917-2022, 2022
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In this study, we investigate the secondary organic aerosol formation potential of decamethylcyclopentasiloxane (D5), which is used as a tracer for volatile chemical products and measured in high concentrations both outdoors and indoors. By performing experiments in different types of reactors, we find that D5’s aerosol formation is highly dependent on OH, and, at low OH concentrations or exposures, D5 forms little aerosol. We also reconcile results from other studies.
Beatrix Rosette Go Mabato, Yan Lyu, Yan Ji, Yong Jie Li, Dan Dan Huang, Xue Li, Theodora Nah, Chun Ho Lam, and Chak K. Chan
Atmos. Chem. Phys., 22, 273–293, https://doi.org/10.5194/acp-22-273-2022, https://doi.org/10.5194/acp-22-273-2022, 2022
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Biomass burning (BB) is a global phenomenon that releases large quantities of pollutants such as phenols and aromatic carbonyls into the atmosphere. These compounds can form secondary organic aerosols (SOAs) which play an important role in the Earth’s energy budget. In this work, we demonstrated that the direct irradiation of vanillin (VL) could generate aqueous SOA (aqSOA) such as oligomers. In the presence of nitrate, VL photo-oxidation can also form nitrated compounds.
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