Atmospheric Chemistry and Physics最新文献

{"title":"Predicted impacts of heterogeneous chemical pathways on particulate sulfur over Fairbanks (Alaska), the Northern Hemisphere, and the Contiguous United States.","authors":"Sara L Farrell, Havala O T Pye, Robert Gilliam, George Pouliot, Deanna Huff, Golam Sarwar, William Vizuete, Nicole Briggs, Fengkui Duan, Tao Ma, Shuping Zhang, Kathleen Fahey","doi":"10.5194/acp-25-3287-2025","DOIUrl":"10.5194/acp-25-3287-2025","url":null,"abstract":"<p><p>A portion of Alaska's Fairbanks North Star Borough was designated as nonattainment for the 2006 24 h fine particulate matter 2.5 μm or less in diameter (PM_2.5) National Ambient Air Quality Standards (NAAQS) in 2009. PM_2.5 NAAQS exceedances in Fairbanks mainly occur during dark and cold winters, when temperature inversions form and trap high emissions at the surface. Sulfate ( <math> <mrow><msubsup><mtext>SO</mtext> <mn>4</mn> <mrow><mn>2</mn> <mo>-</mo></mrow> </msubsup> </mrow> </math> ), often the second-largest contributor to PM_2.5 mass during these wintertime PM episodes, is underpredicted by atmospheric chemical transport models (CTMs). Most CTMs account for primary <math> <mrow><msubsup><mtext>SO</mtext> <mn>4</mn> <mrow><mn>2</mn> <mo>-</mo></mrow> </msubsup> </mrow> </math> and secondary <math> <mrow><msubsup><mtext>SO</mtext> <mn>4</mn> <mrow><mn>2</mn> <mo>-</mo></mrow> </msubsup> </mrow> </math> formed via gas-phase oxidation of sulfur dioxide ( <math> <mrow><msub><mtext>SO</mtext> <mn>2</mn></msub> </mrow> </math> ) and in-cloud aqueous oxidation of dissolved S(IV). Dissolution and reaction of <math> <mrow><msub><mtext>SO</mtext> <mn>2</mn></msub> </mrow> </math> in aqueous aerosols are generally not included in CTMs but can be represented as heterogeneous reactive uptake and may help better represent the high <math> <mrow><msubsup><mtext>SO</mtext> <mn>4</mn> <mrow><mn>2</mn> <mo>-</mo></mrow> </msubsup> </mrow> </math> concentrations observed during Fairbanks winters. In addition, hydroxymethanesulfonate (HMS), a particulate sulfur species sometimes misidentified as <math> <mrow><msubsup><mtext>SO</mtext> <mn>4</mn> <mrow><mn>2</mn> <mo>-</mo></mrow> </msubsup> </mrow> </math> , is known to form during Fairbanks winters. Heterogeneous formation of <math> <mrow><msubsup><mtext>SO</mtext> <mn>4</mn> <mrow><mn>2</mn> <mo>-</mo></mrow> </msubsup> </mrow> </math> and HMS in aerosol liquid water (ALW) was implemented in the Community Multiscale Air Quality (CMAQ) modeling system. CMAQ simulations were performed for wintertime PM episodes in Fairbanks (2008) as well as over the Northern Hemisphere and Contiguous United States (CONUS) for 2015-2016. The added heterogeneous sulfur chemistry reduced model mean sulfate bias by ~0.6 μg m^-3 during a cold winter PM episode in Fairbanks, AK. Improvements in model performance are also seen in Beijing during wintertime haze events (reducing model mean sulfate bias by ~2.9 μgS m^-3). This additional sulfur chemistry also improves modeled summertime <math> <mrow><msubsup><mtext>SO</mtext> <mn>4</mn> <mrow><mn>2</mn> <mo>-</mo></mrow> </msubsup> </mrow> </math> bias in the southeastern US, with implications for future modeling of biogenic organosulfates.</p>","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"25 5","pages":"3287-3312"},"PeriodicalIF":5.1,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12181941/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144473900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensitivity of simulated ammonia fluxes in Rocky Mountain National Park to measurement time resolution and meteorological inputs.","authors":"Lillian E Naimie, Da Pan, Amy P Sullivan, John T Walker, Aleksandra Djurkovic, Bret A Schichtel, Jeffrey L Collett","doi":"10.5194/acp-25-15245-2025","DOIUrl":"10.5194/acp-25-15245-2025","url":null,"abstract":"<p><p>Gaseous ammonia ( <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> ) is an important precursor for secondary aerosol formation and contributes to reactive nitrogen deposition. <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> dry deposition is poorly quantified due to the complex bidirectional nature of <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> atmosphere-surface exchange and lack of high time-resolution in situ <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> concentration and meteorological measurements. To better quantify <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> dry deposition, measurements of <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> were made above a subalpine forest canopy in Rocky Mountain National Park (RMNP) and used with in situ micrometeorology to simulate bidirectional fluxes. <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> dry deposition was largest during the summer, with 47 % of annual net <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> dry deposition occurring in June, July, and August. Because in situ, high time-resolution concentration and meteorological data are often unavailable, the impacts on estimated deposition from utilizing more commonly available biweekly <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> measurements and ERA5 meteorology were evaluated. Fluxes simulated with biweekly <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> concentrations, commonly available from <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> monitoring networks, underestimated <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> dry deposition by 45 %. These fluxes were strongly correlated with 30 min fluxes integrated to a biweekly basis ( <math> <mrow><msup><mi>R</mi> <mn>2</mn></msup> <mo>=</mo> <mn>0.88</mn></mrow> </math> ), indicating that a correction factor could be applied to mitigate the observed bias. Application of an average <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> diel concentration pattern to the biweekly <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> concentration data removed the observed low bias. Annual <math> <mrow><msub><mtext>NH</mtext> <mn>3</mn></msub> </mrow> </math> dry deposition from fluxes simulated with reanalysis meteorological inputs exceeded simulations using in situ meteorology measurements by a factor of 2.</p>","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"25 21","pages":"15245-15261"},"PeriodicalIF":5.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12973231/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147430538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Diagnostic Intercomparison of Modeled Ozone Dry Deposition Over North America and Europe Using AQMEII4 Regional-Scale Simulations.","authors":"Christian Hogrefe, Stefano Galmarini, Paul A Makar, Ioannis Kioutsioukis, Olivia E Clifton, Ummugulsum Alyuz, Jesse O Bash, Roberto Bellasio, Roberto Bianconi, Tim Butler, Philip Cheung, Alma Hodzic, Richard Kranenburg, Aurelia Lupascu, Kester Momoh, Juan Luis Perez-Camanyo, Jonathan E Pleim, Young-Hee Ryu, Roberto San Jose, Martijn Schaap, Donna B Schwede, Ranjeet Sokhi","doi":"10.5194/acp-25-12629-2025","DOIUrl":"10.5194/acp-25-12629-2025","url":null,"abstract":"<p><p>This study analyzes ozone (O3) dry deposition fluxes and velocities (Vd) from twelve regional-scale simulations that were performed over North America and Europe in Phase 4 of the Air Quality Model Evaluation International Initiative (AQMEII4). AQMEII4 collected grid-aggregated and land use (LU)-specific O3 Vd and effective conductances and fluxes for the four major dry deposition pathways. Consistent with recent findings in the AQMEII4 point model intercomparison study, analysis of the grid-aggregated fields shows that grid models with similar Vd can exhibit significant differences in the absolute and relative contributions of the different depositional pathways. Analysis of LU-specific Vd and effective conductances reveals a general increase in model spread compared to grid-aggregated values. This indicates that an analysis of only grid-aggregated deposition diagnostics can mask process-specific differences that exist between schemes. An analysis of AQMEII4 LU distributions across models revealed substantial differences in the spatial patterns and abundance of certain LU categories over both domains, especially for non-forest partially vegetated categories such as agricultural areas, shrubland, and grassland. We demonstrate that these differences can significantly contribute to or even drive differences in LU-specific dry deposition fluxes which can increase the variability in model predictions of ozone. Two recommendations for future deposition-focused modeling studies emerging from the AQMEII4 analyses presented here are to 1) routinely generate diagnostic outputs to advance a process-based understanding of modeled deposition and support impact analyses, and 2) recognize the importance of documenting and analyzing the representation of LU across models and work towards harmonizing this aspect when using air-quality grid models and model ensembles for deposition analyses.</p>","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"25 19","pages":"12629-12656"},"PeriodicalIF":5.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12774381/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145916731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atmospheric oxidation of 1,3-butadiene: influence of seed aerosol acidity and relative humidity on SOA composition and the production of air toxic compounds.","authors":"Mohammed Jaoui, Klara Nestorowicz, Krzysztof J Rudzinski, Michael Lewandowski, Tadeusz E Kleindienst, Julio Torres, Ewa Bulska, Witold Danikiewicz, Rafal Szmigielski","doi":"10.5194/acp-25-1401-2025","DOIUrl":"10.5194/acp-25-1401-2025","url":null,"abstract":"<p><p>This study investigated the effect of relative humidity (RH) on the chemical composition of gas and particle phases formed from the photooxidation of 1,3-butadiene (13BD) in the presence of NO _<i>x</i> under acidified and non-acidified seed aerosol. The experiments were conducted in a 14.5 m³ smog chamber operated in a steady-state mode. Products were identified by high-performance liquid chromatography, gas chromatography-mass spectrometry, and ultrahigh-performance liquid chromatography coupled with high-resolution mass spectrometry. More than 50 oxygenated products were identified, including 33 oxygenated organics, 10 organosulfates (OSs), PAN, APAN, glyoxal, formaldehyde, and acrolein. Secondary organic aerosol (SOA) mass and reaction products formed depended on RH and on the acidity of the seed aerosol. Based on the Extended Aerosol Inorganics Model (E-AIM), the seed aerosol originated from the acidified and non-acidified solutions was found to exist under aqueous and solid phases, respectively. Although the terms \"acidified\" and \"non-acidified\" are true for the solutions from which the seeds were atomized, there are far more fundamental differences between the phase states in which species partition to or from (aqueous/solid), which considerably affects their partitioning and formation mechanisms. SOA mass and most SOA products (i) were higher under acidified seed conditions, where the aerosol particles were deliquescent, than under non-acidified seed conditions, where the aerosol particles did not contain any aqueous phase; (ii) increased with the acidity of the aerosol aqueous phase in the experiments under acidified seed conditions; and (iii) decreased with increasing RH. Glyceric acid, threitols, threonic acids, four dimers, three unknowns, and four organosulfates were among the main species measured under either acidified or non-acidified conditions across all RH levels. Total secondary organic carbon and carbon yield decreased with increasing RH under both acidified and non-acidified seed conditions. The photochemical reactivity of 13BD in our systems decreased with increasing RH and was faster under non-acidified than acidified seed conditions. To determine the contribution of 13BD products to ambient aerosol, we analyzed PM_2.5 samples collected at three European monitoring stations located in Poland. The occurrence of several 13BD SOA products (e.g., glyceric acid, tartronic acid, threonic acid, tartaric acid, and OSs) in the field samples suggests that 13BD could contribute to ambient aerosol formation.</p>","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"25 2","pages":"1401-1432"},"PeriodicalIF":5.1,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12180943/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144473902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating processes influencing simulation of local Arctic wintertime anthropogenic pollution in Fairbanks, Alaska, during ALPACA-2022.","authors":"Natalie Brett, Kathy S Law, Steve R Arnold, Javier G Fochesatto, Jean-Christophe Raut, Tatsuo Onishi, Robert Gilliam, Kathleen Fahey, Deanna Huff, George Pouliot, Brice Barret, Elsa Dieudonné, Roman Pohorsky, Julia Schmale, Andrea Baccarini, Slimane Bekki, Gianluca Pappaccogli, Federico Scoto, Stefano Decesari, Antonio Donateo, Meeta Cesler-Maloney, William Simpson, Patrice Medina, Barbara D'Anna, Brice Temime-Roussel, Joel Savarino, Sarah Albertin, Jingqiu Mao, Becky Alexander, Allison Moon, Peter F DeCarlo, Vanessa Selimovic, Robert Yokelson, Ellis S Robinson","doi":"10.5194/acp-25-1063-2025","DOIUrl":"10.5194/acp-25-1063-2025","url":null,"abstract":"<p><p>Lagrangian tracer simulations are deployed to investigate processes influencing vertical and horizontal dispersion of anthropogenic pollution in Fairbanks, Alaska, during the Alaskan Layered Pollution and Chemical Analysis (ALPACA) 2022 field campaign. Simulated concentrations of carbon monoxide (CO), sulfur dioxide ( <math><mrow><mtext>S</mtext> <msub><mtext>O</mtext> <mn>2</mn></msub> </mrow> </math> ), and nitrogen oxides ( <math><mrow><mtext>N</mtext> <msub><mtext>O</mtext> <mi>x</mi></msub> </mrow> </math> ), including surface and elevated sources, are the highest at the surface under very cold stable conditions. Pollution enhancements above the surface (50-300 m) are mainly attributed to elevated power plant emissions. Both surface and elevated sources contribute to Fairbanks' regional pollution that is transported downwind, primarily to the south-west, and may contribute to wintertime Arctic haze. Inclusion of a novel power plant plume rise treatment that considers the presence of surface and elevated temperature inversion layers leads to improved agreement with observed CO and <math><mrow><mtext>N</mtext> <msub><mtext>O</mtext> <mi>x</mi></msub> </mrow> </math> plumes, with discrepancies attributed to, for example, displacement of plumes by modelled winds. At the surface, model results show that observed CO variability is largely driven by meteorology and, to a lesser extent, by emissions, although simulated tracers are sensitive to modelled vertical dispersion. Modelled underestimation of surface <math><mrow><mtext>N</mtext> <msub><mtext>O</mtext> <mi>x</mi></msub> </mrow> </math> during very cold polluted conditions is considerably improved following the inclusion of substantial increases in diesel vehicle <math><mrow><mtext>N</mtext> <msub><mtext>O</mtext> <mi>x</mi></msub> </mrow> </math> emissions at cold temperatures (e.g. a factor of 6 at -30°C). In contrast, overestimation of surface <math><mrow><mtext>S</mtext> <msub><mtext>O</mtext> <mn>2</mn></msub> </mrow> </math> is attributed mainly to model deficiencies in vertical dispersion of elevated (5-18 m) space heating emissions. This study highlights the need for improvements to local wintertime Arctic anthropogenic surface and elevated emissions and improved simulation of Arctic stable boundary layers.</p>","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"25 2","pages":"1063-1104"},"PeriodicalIF":5.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12180936/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144473903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Retention of <i>α</i> -pinene oxidation products and nitro-aromatic compounds during riming","authors":"C. Borchers, Jackson Seymore, Martanda Gautam, Konstantin Dörholt, Yannik Müller, Andreas Arndt, Laura Gömmer, Florian Ungeheuer, Miklós Szakáll, Stephan Borrmann, Alexander Theis, Alexander L. Vogel, Thorsten Hoffmann","doi":"10.5194/acp-24-13961-2024","DOIUrl":"https://doi.org/10.5194/acp-24-13961-2024","url":null,"abstract":"Abstract. Riming is an important growth process of graupel and hailstones in the mixed-phase zones of clouds, during which supercooled liquid droplets freeze on the surface of ice particles by contact. Compounds dissolved in the supercooled cloud droplets can remain in the ice or be released to the gas phase during freezing, which might play an important role in the vertical redistribution of these compounds in the atmosphere by convective cloud processes. This is important for estimating the availability of these compounds in the upper troposphere, where organic matter can promote new particle formation and growth. The amount of organic material remaining in the ice phase can be described by the retention coefficient. Experiments were performed in the Mainz vertical wind tunnel under dry and wet growth conditions (temperature from −12 to −3 °C and a liquid water content (LWC) of 0.9±0.2 g m−3 and 2.2±0.2 g m−3) as well as with different pH values (4 and 5.6) to obtain the retention coefficients of α-pinene oxidation products and nitro-aromatic compounds. For cis-pinic acid, cis-pinonic acid, and (−)-pinanediol, mean retention coefficients of 0.96±0.07, 0.92±0.11, and 0.98±0.08 were obtained. 4-Nitrophenol, 4-nitrocatechol, 2-nitrobenzoic acid, and 2-nitrophenol showed mean retention coefficients of 1.01±0.07, 1.01±0.14, 0.99±0.04, and 0.21±0.12. Only the retention coefficient of 2-nitrophenol showed a dependence on temperature, growth regime, and pH. This is in accordance with previous studies, which showed a dependence between the dimensionless effective Henry's law constant H* and the retention coefficient for inorganic and small organic molecules. Our results reveal that this correlation can also be applied to more complex organic molecules and that retention under these conditions is not a significant factor for molecules with H* below 103, while retention close to 1 can be expected for compounds with H* above 108.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"24 24","pages":"13961-13974"},"PeriodicalIF":0.0,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://acp.copernicus.org/articles/24/13961/2024/acp-24-13961-2024.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147892657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of chemical production and depositional losses on formaldehyde in the Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM).","authors":"T Nash Skipper, Emma L D'Ambro, Forwood C Wiser, V Faye McNeill, Rebecca H Schwantes, Barron H Henderson, Ivan R Piletic, Colleen B Baublitz, Jesse O Bash, Andrew R Whitehill, Lukas C Valin, Asher P Mouat, Jennifer Kaiser, Glenn M Wolfe, Jason M St Clair, Thomas F Hanisco, Alan Fried, Bryan K Place, Havala O T Pye","doi":"10.5194/acp-24-12903-2024","DOIUrl":"10.5194/acp-24-12903-2024","url":null,"abstract":"<p><p>Formaldehyde (HCHO) is an important air pollutant with direct cancer risk and ozone-forming potential. HCHO sources are complex because HCHO is both directly emitted and produced from oxidation of most gas-phase reactive organic carbon. We update the secondary production of HCHO in the Community Regional Atmospheric Chemistry Multiphase Mechanism (CRACMM) in the Community Multiscale Air Quality (CMAQ) model. Production of HCHO from isoprene and monoterpenes is increased, correcting an underestimate in the current version. Simulated June-August surface HCHO during peak photochemical production (11:00-15:00 LT, local time) increased by 0.6 ppb (32 %) over the southeastern USA and by 0.2 ppb (13 %) over the contiguous USA. The increased HCHO compares more favorably with satellite-based observations from the TROPOspheric Monitoring Instrument (TROPOMI) and from aircraft-based observations. Evaluation against hourly surface observations indicates a missing nighttime sink that can be improved by increased nighttime deposition, which reduces June-August nocturnal (20:00-04:00 LT) surface HCHO by 1.1 ppb (36 %) over the southeastern USA and 0.5 ppb (29 %) over the contiguous USA. The ability of CRACMM to capture peak levels of HCHO at midday is improved, particularly at sites in the northeastern USA, while peak levels at sites in the southeastern USA are improved, although still lower than observed. Using established risk assessment methods, lifetime exposure of the population in the contiguous USA (~320 million) to ambient HCHO levels predicted here may result in 6200 lifetime cancer cases, with 40 % from controllable anthropogenic emissions of nitrogen oxides and reactive organic compounds. Chemistry updates will be available in CRACMM version 2 (CRACMM2) in CMAQv5.5.</p>","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"24 22","pages":"12903-12924"},"PeriodicalIF":5.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12180760/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144473901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formation of reactive nitrogen species promoted by iron ions through the photochemistry of a neonicotinoid insecticide","authors":"Zhu Ran, Yanan Hu, Yuanzhe Li, Xiaoya Gao, Can Ye, Shuai Li, Xiao Lu, Yongming Luo, Sasho Gligorovski, Jiangping Liu","doi":"10.5194/acp-24-11943-2024","DOIUrl":"https://doi.org/10.5194/acp-24-11943-2024","url":null,"abstract":"Abstract. Nitrous acid (HONO) and nitrogen oxides (NOx=NO+NO2) are important atmospheric pollutants and key intermediates in the global nitrogen cycle, but their sources and formation mechanisms are still poorly understood. Here, we investigated the effect of soluble iron (Fe3+) on the photochemical behavior of a widely used neonicotinoid (NN) insecticide, nitenpyram (NPM), in the aqueous phase. The yields of HONO and NOx increased significantly when NPM solution was irradiated in the presence of iron ions (Fe3+). We propose that the enhanced HONO and NO2 emissions from the photodegradation of NPM in the presence of iron ions result from the redox cycle between Fe3+ and Fe2+ and the generated reactive oxygen species (ROS) by electron transfer between the excited triplet state of NPM and molecular oxygen (O2). Using the laboratory-derived parameterization based on kinetic data and gridded downward solar radiation, we estimate that the photochemistry of NPM induced by Fe3+ releases 0.50 and 0.77 Tg N yr−1 of NOx and HONO, respectively, into the atmosphere. This study suggests a novel source of HONO and NOx during daytime and potentially helps to narrow the gap between field observations and model outcomes of HONO in the atmosphere. The suggested photochemistry of NPM can be an important contribution to the global nitrogen cycle affecting the atmospheric oxidizing capacity and climate change.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"24 20","pages":"11943-11954"},"PeriodicalIF":0.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://acp.copernicus.org/articles/24/11943/2024/acp-24-11943-2024.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147881652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The interplay between aqueous replacement reaction and the phase state of internally mixed organic/ammonium aerosols","authors":"Hui Yang, Fengfeng Dong, Xia Li, Qishen Huang, Shufeng Pang, Yunhong Zhang","doi":"10.5194/acp-24-11619-2024","DOIUrl":"https://doi.org/10.5194/acp-24-11619-2024","url":null,"abstract":"Abstract. Atmospheric secondary aerosols are often internally mixed with organic and inorganic components, particularly dicarboxylic acids, ammonium, sulfate, nitrate, and chloride. These complex compositions enable aqueous reaction between organic and inorganic species, significantly complicating aerosol phase behavior during aging and making phase predictions challenging. We investigated carboxylate–ammonium salt mixtures using attenuated total reflection Fourier-transformed infrared spectroscopy (ATR-FTIR). The mono-, di-, and tricarboxylates included sodium pyruvate (SP), sodium tartrate (ST), and sodium citrate (SC), while the ammonium salts included NH4NO3, NH4Cl, and (NH4)2SO4. Our results demonstrated that aqueous replacement reactions between carboxylates and ammonium salts were promoted by the formation and depletion of NH3 as relative humidity (RH) changed. For SP/ammonium aerosols, NaNO3 and Na2SO4 crystallized from 35.7 % to 12.7 % and from 65.7 % to 60.1 % RH, respectively, which is lower than the values for pure inorganics (62.5 ± 9 %–32 % RH for NaNO3 and 82 ± 7 %–68 ± 5 % RH for Na2SO4). Upon hydration, the crystalline Na2SO4 and NaNO3 deliquesced at 88.8 %–95.2 % and 76.5 ± 2 %–81.9 %, which is higher than the values of pure Na2SO4 (74 ± 4 %–98 % RH) and NaNO3 (65 %–77.1 ± 3 % RH). In contrast, reaction between ST or SC and (NH4)2SO4 was incomplete due to the gel structure at low RH. Unexpectedly, aqueous Na2SO4 crystallized upon humidification in ST/(NH4)2SO4 particles at 43.6 % RH and then deliquesced with increasing RH. This is attributed to increased ion mobility in viscous particles, leading to nucleation and growth of Na2SO4 crystals. Our findings highlight the intricate interplay between chemical components within organic/inorganic aerosol and the impact of replacement reactions on aerosol aging, phase state, and subsequently atmospheric processes.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"24 20","pages":"11619-11635"},"PeriodicalIF":0.0,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://acp.copernicus.org/articles/24/11619/2024/acp-24-11619-2024.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147883409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using a region-specific ice-nucleating particle parameterization improves the representation of Arctic clouds in a global climate model","authors":"Astrid Bragstad Gjelsvik, Robert Oscar David, Tim Carlsen, Franziska Hellmuth, Stefan Hofer, Zachary McGraw, Harald Sodemann, Trude Storelvmo","doi":"10.5194/egusphere-2024-1879","DOIUrl":"https://doi.org/10.5194/egusphere-2024-1879","url":null,"abstract":"<strong>Abstract.</strong> Projections of global climate change and Arctic amplification are sensitive to the representation of low-level cloud phase in climate models. Ice-nucleating particles (INPs) are necessary for primary cloud ice formation at temperatures above approximately -38 °C, and thus significantly affect cloud phase and cloud radiative effect. Due to their complex and insufficiently understood variability, INPs constitute an important modelling challenge, especially in remote regions with few observations, such as the Arctic. In this study, INP observations were carried out at Andenes, Norway in March 2021. These observations were used as a basis for an Arctic-specific and purely temperature-dependent INP parameterization, and implemented into the Norwegian Earth System Model. This implementation results in an annual average increase in cloud liquid water path (CLWP) of 70 % for the Arctic, and improves the representation of cloud phase compared to satellite observations. The change in CLWP in boreal autumn and winter is found to likely be the dominant contributor to the annual average increase in net surface cloud radiative effect of 2 W m^-2. This large surface flux increase brings the simulation into better agreement with Arctic ground-based measurements. Despite that the model cannot respond fully to the INP parameterization change due to fixed sea surface temperatures, Arctic surface air temperature increases with 0.7 °C in boreal autumn. These findings indicate that INPs could have a significant impact on Arctic climate, and that a region-specific INP parameterization can be a useful tool to improve cloud representation in the Arctic region.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"7 1","pages":""},"PeriodicalIF":6.3,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141561307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}