Environmental science: atmospheres最新文献

{"title":"Correction: Online characterisation of oxidative potential and reactive oxygen species of fresh and aged aircraft turbine and ship engine particulate emissions.","authors":"Alexandre Barth, Battist Utinger, Quanfu He, Andreas Paul, Anni Hartikainen, Mika Ihalainen, Uwe Etzien, Sandra Piel, Marius Rohkamp, Ajit Mudan, Benedikt Gündling, Tuukka Kokkola, Thorsten Streibel, Martin Sklorz, Hendryk Czech, Johan Øvrevik, Thomas Adam, Andreas Hupfer, Thorsten Hohaus, Olli Sippula, Yinon Rudich, Bert Buchholz, Ralf Zimmermann, Markus Kalberer","doi":"10.1039/d6ea90037b","DOIUrl":"10.1039/d6ea90037b","url":null,"abstract":"<p><p>[This corrects the article DOI: 10.1039/D5EA00174A.].</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13651767/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149168135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Online characterisation of oxidative potential and reactive oxygen species of fresh and aged aircraft turbine and ship engine particulate emissions.","authors":"Alexandre Barth, Battist Utinger, Quanfu He, Andreas Paul, Anni Hartikainen, Mika Ihalainen, Uwe Etzien, Sandra Piel, Marius Rohkamp, Ajit Mudan, Benedikt Gündling, Kokkola Tuuka, Thorsten Streibel, Martin Sklorz, Hendryk Czech, Johan Øvrevik, Thomas Adam, Andreas Hupfer, Thorsten Hohaus, Olli Sippula, Yinon Rudich, Bert Buchholz, Ralf Zimmermann, Markus Kalberer","doi":"10.1039/d5ea00174a","DOIUrl":"10.1039/d5ea00174a","url":null,"abstract":"<p><p>Anthropogenic particulate matter (PM) emissions from the transport sector are a major contributor to global air pollution and associated adverse health effects. While the health impacts of PM are well-documented, the specific chemical and physical properties driving its toxicity, such as oxidative potential (OP) remain poorly understood and quantified. This study investigates the OP activity of PM emissions from a small jet engine combustion chamber (using JP-8 fuel) and a marine diesel engine (using low sulfur Heavy Fuel Oil, LS-HFO, and Marine Gas Oil, MGO) under fresh and photochemically aged conditions. Using a novel online instrument the Online Oxidative Potential Ascorbic Acid Instrument (OOPAAI)-we quantified in real-time OP activity of PM. Fresh emissions were sampled directly, while the aged emissions were processed in a photochemical reactor to simulate atmospheric ageing for 1 to 12 equivalent days. Our results illustrate that mass-normalized OP activity showed no significant change with particle ageing for ship emissions but increased substantially for aircraft emissions. The average chemical composition of PM, characterized by average O/C and H/C ratios of the organic mass fraction, indicated increasing oxidation with ageing, correlating well with higher OP activity of aircraft emissions. These findings highlight the importance of considering both fresh and aged emissions in assessing the health impacts of PM emission from fossil fuel sources, as atmospheric processing can drastically alter their oxidative properties.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":"1629-1638"},"PeriodicalIF":3.2,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13596030/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149027097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fine-scale variations in black carbon concentrations and the chemical composition of total suspended particulate matter at a heavy traffic road intersection in Addis Ababa, Ethiopia.","authors":"Andualem Ayele, Haley Royer, Marc N Fiddler, Andualem Mekonnen, Eyale Bayable, Birbiraw Deresse, Tesfaye Mamo, Jason D Surratt, Solomon Bililign","doi":"10.1039/d6ea00100a","DOIUrl":"10.1039/d6ea00100a","url":null,"abstract":"<p><p>Atmospheric aerosols in Ethiopian urban environments remain poorly characterized. This study investigated the spatiotemporal variability of equivalent black carbon (eBC) concentrations and the molecular composition of organics in total suspended particulate matter (TSPM) collected in urban Addis Ababa. The level of eBC was monitored at major traffic intersections from January 2024 to December 2025. eBC concentrations were measured using a portable MicroAeth AE51. TSPM samples were collected on Teflon filters using a Leland Legacy sampler and analyzed by reversed-phase liquid chromatography coupled to electrospray ionization interfaced to quadrupole time-of-flight mass spectrometry (RPLC-ESI-QTOFMS) operated in the negative ion mode. The study revealed substantial spatiotemporal variability in eBC concentration, with a mean of 26.24 ± 42.81 µg m^-3. Episodic peaks exceeding 1000 µg m^-3 were recorded at heavily trafficked locations such as Kality. Diurnal patterns exhibited distinct morning and evening rush-hour maxima. Non-targeted analysis identified 74 compounds (with molecular weights spanning from 102 to 370 g mol^-1), 41 of which were structurally assigned with high confidence. The organic fraction of TSPM was dominated by oxygenated (CHO) and nitrogen-containing (CHON) species, including carboxylic acids, oxocarboxylic acids, phenolics, aromatic acids, and nitro-aromatic compounds. Spatial heterogeneity was evident, particularly at Awotobistera, where it showed enrichment in biomass-burning tracers and lignin-derived compounds. Twenty-three identified compounds functioned as brown carbon chromophores, including nitro-aromatic and oxygenated aromatic species. Their occurrence suggests contributions from both primary combustion sources and atmospheric processing, although source apportionment was beyond the scope of this study. These findings provide a baseline for future investigations of aerosol sources, atmospheric processing, and urban air quality dynamics in Addis Ababa.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":"1551-1563"},"PeriodicalIF":3.2,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13548030/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148908273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydroxyl radical as an indoor oxidant.","authors":"Charles J Weschler, William W Nazaroff","doi":"10.1039/d6ea00074f","DOIUrl":"10.1039/d6ea00074f","url":null,"abstract":"<p><p>The hydroxyl radical (OH) is the dominant oxidant in outdoor air. Indoors, its role is secondary to ozone (O₃). However, growing evidence indicates that OH contributes more significantly to indoor oxidation chemistry than previously recognized. This review critically examines the state of knowledge regarding OH as an indoor oxidant, synthesizing findings from modeling studies, laboratory experiments, and field measurements. Indoor OH concentrations range from 1 to 100 ppq under common conditions, with a central tendency of ∼5 ppq-one to two orders of magnitude below urban daytime outdoor levels and comparable to urban nighttime values. The primary sources of OH in occupied environments are gas-phase reactions between ozone and monoterpenes or alkenes, particularly limonene, 6-methyl-5-hepten-2-one, and geranyl acetone. These compounds are also important sinks for OH, and these dual roles tend to buffer indoor OH concentrations. Photolysis of nitrous acid can be an important indoor OH source under some conditions. The dominant sink for indoor OH is homogeneous gas-phase reactions with volatile organic compounds (VOCs). Total OH reactivity is commonly on the order of 50 s^-1 for occupied residences and can be much higher during events that release VOCs, such as cooking and cleaning. Radical cycling <i>via</i> the NO + HO₂ reaction can significantly amplify indoor OH concentrations, depending on indoor NO levels. OH-initiated autoxidation chemistry contributes to the long-term oxidation of semivolatile organic compounds on indoor surfaces. OH chemistry, spatially variable and strongly influenced by occupant behavior, warrants continued investigation given its relevance to indoor air quality and human health.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":"1328-1355"},"PeriodicalIF":3.2,"publicationDate":"2026-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13496323/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148802417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NO and NO₂ reactions with oxygenated peroxy radicals lead to indistinguishable product compositions: computational insights from cyclohexene oxidation in presence of NO _<i>x</i>.","authors":"Sakshi Jha, Avinash Kumar, Prasenjit Seal, Siddharth Iyer, Matti Rissanen","doi":"10.1039/d5ea00151j","DOIUrl":"10.1039/d5ea00151j","url":null,"abstract":"<p><p>This study presents a computational investigation into the role of nitrogen oxides (NO _<i>x</i> ) in modulating gas-phase cyclohexene oxidation by ozone (O₃) and hydroxyl radical (OH) through their reactions with peroxy radicals (RO₂) formed during the oxidation sequence. While NO₂ suppresses further oxidation by forming peroxynitrates (RO₂-NO₂), NO can either enhance autoxidation through the formation of reactive alkoxy radicals (RO) or terminate the radical chain <i>via</i> organic nitrate (RO-NO₂) formation. In this work, we evaluate the binding affinities of NO _<i>x</i> toward RO₂ molecules formed at different oxidation stages at DLPNO-CCSD(T)/aug-cc-pVTZ//ωB97X-D/aug-cc-pVTZ level of theory. This is followed by dissociation rate coefficient calculations using detailed balance and master equation simulations, indicating the lifetime and fragmentation pathways of the covalently bound RO₂-NO _<i>x</i> molecules. The results suggest a tendency toward stronger RO₂-NO _<i>x</i> stabilization with increasing oxidation stage, with a strong influence from molecular structure. This study also explores the rarely studied dissociation of RO₂-NO₂ into RO and NO₃. Furthermore, by computing the binding enthalpies of NO₃ ^- and with RO₂-NO _<i>x</i> , this work assesses the detectability of these N-containing oxidation products by the nitrate ion based chemical ionization mass spectrometer (NO₃ ^--CIMS). The results are benchmarked against nitrophenol compounds known to form stable nitrate adducts. This analysis highlights potential detection biases associated with measuring nitrate-functionalized compounds using NO₃ ^--CIMS as variations in molecular structure and clustering tendency influence signal intensities. Overall, these results highlight the regulatory roles of NO and NO₂ in hydrocarbon oxidation and offer insights to improve interpretation of these oxygenated organic nitrates in atmospheric CIMS measurements.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":"1286-1301"},"PeriodicalIF":3.2,"publicationDate":"2026-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13366502/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148450840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Short-term exposure to ammonium sulfate modifies ice nucleation by alpha-alumina but not organic monolayers or microplastics.","authors":"Lian Pharoah, Teresa M Seifried, Gren N Patey, Anita Lam, Allan K Bertram","doi":"10.1039/d5ea00157a","DOIUrl":"10.1039/d5ea00157a","url":null,"abstract":"<p><p>Accurate predictions of ice cloud formation require understanding how ammonium sulfate affects the freezing behavior of ice-nucleating substances (INSs). This knowledge is also essential for evaluating the reliability of a freezing assay used to identify ice-nucleating mineral dusts in atmospheric samples. Here, we used a droplet freezing technique to investigate the effects of short-term exposure (minutes) to ammonium sulfate on six INSs: two α-alumina samples (submicrometer, < 1 µm, and supermicrometer, > 1 µm), two alcohol monolayers (C₂₂H₄₅OH and C₃₀H₆₁OH), and two microplastics (polyethylene terephthalate and low-density polyethylene). Exposure to ammonium sulfate did not change the ice-nucleating properties of the alcohol monolayers or microplastics. In contrast, submicrometer α-alumina exhibited enhanced ice-nucleating ability following ammonium sulfate exposure, while the supermicrometer α-alumina showed no change, despite similar bulk composition. This size-dependent response is consistent with differences in surface hydroxy protonation states. More deprotonated, negatively charged surface hydroxy groups can attract ammonium cations, modifying interfacial hydrogen-bonding networks and stabilizing nascent ice clusters. These findings should be considered when evaluating submicrometer α-alumina for stratospheric aerosol injection as a solar management strategy. In addition, our results support the use of ammonium sulfate-based freezing assays for identifying ice-nucleating mineral components in atmospheric samples.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":"1417-1431"},"PeriodicalIF":3.2,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13383377/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148610778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid new particle formation driven by methanesulfonic acid and amines.","authors":"Hannah Klebach, Lucía Caudillo-Plath, Martin Heinritzi, Douglas M Russell, Birte Rörup, Rima Baalbaki, Jiali Shen, Eva Sommer, Andreas Kürten, Dina Alfaouri, Joao Almeida, António Amorim, Lisa J Beck, Hannah Beckmann, Moritz Berntheusel, Theodoros Christoudias, Lubna Dada, Jenna DeVivo, Neil Donahue, Jonathan Duplissy, Imad El Haddad, Armin Hansel, Hartwig Harder, Xu-Cheng He, Markku Kulmala, Felix Kunkler, Katrianne Lehtipalo, Lu Liu, Bernhard Mentler, Tuukka Petäjä, Pedro Rato, Sarah Richter, Siegfried Schobesberger, Wiebke Scholz, Mario Simon, Roseline C Thakur, António Tomé, Yandong Tong, Jens Top, Rainer Volkamer, Paul M Winkler, Boxing Yang, Marcel Zauner-Wieczorek, Jiangyi Zhang, Jasper Kirkby, Joachim Curtius","doi":"10.1039/d5ea00081e","DOIUrl":"10.1039/d5ea00081e","url":null,"abstract":"<p><p>The formation and radiative properties of clouds in the marine boundary layer are highly sensitive to the number of cloud condensation nuclei (CCN), which largely originate from new particle formation. At present, most climate models only consider new particle formation from sulfuric acid (SA), in pristine marine regions produced <i>via</i> oxidation of dimethyl sulfide (DMS) emitted by phytoplankton. However, DMS oxidation also yields methanesulfonic acid (MSA) - often in higher amounts than SA under cool conditions (<10 °C) - yet MSA's role in NPF remains elusive. Here, we present results from the CERN CLOUD chamber at temperatures of -10 °C and +5 °C, demonstrating NPF from MSA and amines (dimethylamine, DMA, and trimethylamine, TMA). We isolated effects of MSA from SA by generating MSA from an evaporator at concentrations between 10⁵ and 10⁸ cm^-3. We find MSA and DMA form particles at +5 °C but nucleation rates (<i>J</i> _1.7) are slow, reaching about 1 cm^-3 s^-1 at MSA concentrations of 5 × 10⁷ cm^-3. However, in the presence of low concentrations of SA (below 10⁶ cm^-3) and 2-15 pptv DMA, MSA at few 10⁷ cm^-3 strongly enhances SA-DMA nucleation, reaching up to 80 cm^-3 s^-1. Our measurements confirm MSA together with SA and DMA molecules in initial molecular clusters during nucleation. We find TMA less effective than DMA for new particle formation, likely resulting from steric hindrance of the additional methyl group. Our findings show that MSA can boost NPF rates by 1-2 orders of magnitude in pristine marine environments and should be incorporated in climate models.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":"1028-1039"},"PeriodicalIF":3.2,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13334493/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148439161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of humidity on aerosol growth from methanesulfonic acid.","authors":"Wenjuan Yu, Rima Baalbaki, Jiali Shen, Jenna DeVivo, Lucía Caudillo-Plath, Eva Sommer, Arto Heitto, Hannah Klebach, Douglas M Russell, António Amorim, Hannah Beckmann, Nirvan Bhattacharyya, Vine Blankenship, Anouck Chassaing, Romulo Cruz-Simbron, Lubna Dada, Aenne Jacobshagen, Bernhard Judmaier, Milin Kaniyodical Sebastian, Ruth Konrat, Timm Krüger, Felix Kunkler, Clara J Lietzke, Lu Liu, Roy Mauldin, Bernhard Mentler, Aleksandra Morawiec, Pedro Rato, Birte Rörup, Samuel Ruhl, Wiebke Scholz, Mario Simon, Alexandria Stinchfield, António Tomé, Yandong Tong, Jens Top, Nsikanabasi Silas Umo, Gabriela R Unfer, Lejish Vettikkat, Jakob Weissbacher, Christos Xenofontos, Boxing Yang, Marcel Zauner-Wieczorek, Jiangyi Zhang, Zhensen Zheng, Theodoros Christoudias, Joachim Curtius, Imad El Haddad, Richard Flagan, Armin Hansel, Hartwig Harder, Andreas Kürten, Ottmar Möhler, Tuukka Petäjä, Rainer Volkamer, Paul M Winkler, Douglas R Worsnop, Markku Kulmala, Neil M Donahue, Jasper Kirkby, Taina Yli-Juuti, Ilona Riipinen, Xu-Cheng He, Katrianne Lehtipalo","doi":"10.1039/d5ea00123d","DOIUrl":"10.1039/d5ea00123d","url":null,"abstract":"<p><p>Methanesulfonic acid (MSA; CH₃SO₃H), produced by oxidation of dimethylsulfide (DMS; CH₃SCH₃), is a key precursor for aerosols in the marine boundary layer and free troposphere. Laboratory experiments show that MSA contributes to both particle nucleation and subsequent growth, often together with sulfuric acid (H₂SO₄) and base vapours such as ammonia (NH₃). However, the influence of relative humidity (RH) on MSA condensation to particles remains uncertain. Here, in experiments conducted under low NH₃ conditions (<4 parts per trillion by volume, pptv) at the CERN Cosmics Leaving OUtdoor Droplets (CLOUD) chamber, we find that RH critically regulates the participation of MSA in the initial growth of newly formed particles. Between +10 °C and -10 °C, MSA drives rapid particle growth at high RH (>50%), whereas its contribution at low RH (<16%) is negligible. When comparing with aerosol process models such as the Model for Acid-Base Chemistry in Nanoparticle Growth (MABNAG), we find that the model fails to match our laboratory results. In particular, our measurements show that MSA drives rapid particle growth at substantially warmer temperatures and lower relative humidities than predicted by the Extended Aerosol Inorganic Model (E-AIM). This highlights the importance of further experiments to fully quantify the effect of RH on MSA particle growth and evaporation, and incorporating these measurements in aerosol models. This will be essential for accurately representing the important role of MSA in marine aerosols in global models, particularly in cold, low-NH₃ environments like polar regions and the free troposphere.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":"1356-1367"},"PeriodicalIF":3.2,"publicationDate":"2026-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13334494/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148439188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nucleation of α-pinene oxidation products with sulfuric acid.","authors":"Eva Sommer, João Almeida, Wenjuan Yu, Mario Simon, Felix Möller, Christos Xenofontos, Andrea Pozzer, Zhensen Zheng, Nirvan Bhattacharyya, Dina Alfaouri, Samira Atabakhsh, Rima Baalbaki, Hannah Beckmann, Moritz Berntheusel, Pia Bogert, Mattia Busato, Manjula Canagaratna, Lucía Caudillo-Plath, Anouck Chassaing, Romulo Cruz-Simbron, Lubna Dada, Jenna DeVivo, Jonathan Duplissy, Hamish Gordon, Manuel Granzin, Lena Große Schute, Herbert G Hartl, Ella Hirvensalo, Aenne Jacobshagen, Bernhard Judmaier, Milin Kaniyodical Sebastian, Hannah Klebach, Paap Koemets, Matthias Kohl, Ruth Konrat, Timm Krüger, Felix Kunkler, Andreas Kürten, Markus Leiminger, Clara J Lietzke, Lu Liu, Roy Mauldin, Bernhard Mentler, Aleksandra Morawiec, Markus Müller, Tuukka Petäjä, Alessia Pignatelli, Pedro Rato, Tobias Reinecke, Sarah Richter, Birte Rörup, Samuel Ruhl, Douglas M Russell, Wiebke Scholz, Jiali Shen, Alexandria Stinchfield, Roseline C Thakur, Yandong Tong, Jens Top, Nsikanabasi Silas Umo, Jakob Weissbacher, Boxing Yang, Marcel Zauner-Wieczorek, Jiangy Zhang, Antonio Amorim, Urs Baltensberger, Theodoros Christoudias, Joachim Curtius, Neil M Donahue, Imad El Haddad, Richard C Flagan, Armin Hansel, Hartwig Harder, Xu-Cheng He, Heikki Junninen, Markku Kulmala, Katrianne Lehtipalo, Jos Lelieveld, Ottmar Möhler, Siegfried Schobesberger, António Tomé, Rainer Volkamer, Douglas R Worsnop, Antti Onnela, Paul M Winkler, Jasper Kirkby","doi":"10.1039/d6ea00046k","DOIUrl":"10.1039/d6ea00046k","url":null,"abstract":"<p><p>Particle nucleation from trace atmospheric vapours is important for climate since it gives rise to more than half of global cloud condensation nuclei. Sulfuric acid (H₂SO₄) has long been recognised to drive particle nucleation in the atmosphere and, more recently, highly oxygenated products of biogenic vapours-in particular monoterpenes such as α-pinene (C₁₀H₁₆)-have also been shown to nucleate under atmospheric conditions, without requiring additional vapours. This raises the question of whether a nucleation synergy exists between α-pinene oxygenated organic molecules (AP-OOM) and H₂SO₄, as has been suggested by early studies. Here we report new particle formation from AP-OOM and H₂SO₄ in the absence of base vapours such as ammonia (NH₃), measured in experiments performed with the CERN CLOUD (Cosmics Leaving Outdoor Droplets) chamber at cool boundary layer temperatures of -10 °C and +5 °C. We find that AP-OOM nucleation rates increase strongly when H₂SO₄ concentrations exceed around 10⁶ cm^-3. The enhancement is synergistic and cannot be explained as a simple linear addition of independent chemical systems. Above this threshold, the nucleation rate depends approximately linearly on H₂SO₄ concentration, in contrast with the strong sensitivity to H₂SO₄ for H₂SO₄-NH₃ nucleation. Nucleation rates are 10-100-fold higher in the presence of ions from galactic cosmic rays or from the CERN pion beam. Based on these measurements, we have parameterised a temperature-dependent H₂SO₄-AP-OOM nucleation rate in the absence of base vapours and implemented it in the EMAC (ECHAM/MESSy Atmospheric Chemistry) Earth system model. In comparison with a parameterisation developed in an earlier study [Riccobono <i>et al.</i>, <i>Science</i>, 2014, <b>344</b>, 717-721.], the new parameterisation indicates sharply reduced nucleation rates in the boundary layer over warm regions, and increased rates over northern boreal forests.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" ","pages":"1131-1146"},"PeriodicalIF":3.2,"publicationDate":"2026-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13285975/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148310540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of an electrostatic precipitator on particle mass, composition, and number size distributions in residential wood combustion emissions","authors":"Narayan Babu Dhital, Juho Louhisalmi, Henna Rinta-Kiikka, Sampsa Väätäinen, Jani Leskinen, Olli Sippula and Jarkko Tissari","doi":"10.1039/D5EA00175G","DOIUrl":"https://doi.org/10.1039/D5EA00175G","url":null,"abstract":"<p >Residential wood combustion (RWC) is an increasingly dominant source of particulate matter (PM) pollution in Europe. Electrostatic precipitators (ESPs) are a promising technology for controlling particle mass emissions from RWC appliances, but their influence on particle number concentrations (PNC) is highly variable, as they may occasionally increase PNC. In this study, we evaluated the effect of an ESP on PM<small>₁</small>, black carbon (BC), elemental carbon (EC), organic carbon (OC), and particle number size distributions in emissions from wood-fueled stoves commonly used in Finland, under conditions spanning a wide range of upstream emission loads. Experiments were conducted in a state-of-the-art small-scale combustion simulation and measurement facility. The emission reduction efficiencies of the ESP were 75.7% ± 4.7% for PM<small>₁</small>, 83.2% ± 14.2% for EC, and 70.1% ± 12.6% for OC. The operation of ESP not only reduced PM<small>₁</small> concentrations but also influenced particle composition and optical properties with its differential collection efficiencies for EC and OC. Moreover, it reduced PNC within the size range of 0.13–2.5 µm, but nucleation-mode PNC occasionally increased, suggesting possible new particle formation. Additionally, the combustion conditions that showed negative efficiencies for PNC had higher upstream organic gaseous carbon concentrations and higher OC : EC ratios compared to those with positive efficiencies, suggesting that organics-rich flue gas may contribute to increased PNC when ESPs are used. These findings highlight the importance of controlling organic emissions to improve the overall emission reduction performance of ESPs.</p>","PeriodicalId":72942,"journal":{"name":"Environmental science: atmospheres","volume":" 6","pages":" 853-866"},"PeriodicalIF":3.2,"publicationDate":"2026-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2026/ea/d5ea00175g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148261557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}