Atmospheric Environment: X最新文献

{"title":"Characterization of atmospheric aerosol and its carbonaceous components at a central Mediterranean site: A multi-method approach using optical, physical, and isotopic techniques","authors":"Dalila Peccarrisi ,&nbsp;Mattia Fragola ,&nbsp;Salvatore Romano ,&nbsp;Federica Fanigliulo ,&nbsp;Giorgio Giuseppe Carbone ,&nbsp;Lucio Maruccio ,&nbsp;Daniele Contini ,&nbsp;Gianluca Quarta ,&nbsp;Lucio Calcagnile","doi":"10.1016/j.aeaoa.2025.100380","DOIUrl":"10.1016/j.aeaoa.2025.100380","url":null,"abstract":"<div><div>A new analytical approach combining aethalometer measurements, organic and elemental carbon (OC/EC) analysis, Scanning Electron Microscopy (SEM), Particle Induced X-ray Emission (PIXE), and Isotope Ratio Mass Spectrometry (IRMS) was used to characterize aerosol properties and its carbonaceous component in Lecce (Italy), located in the Central Mediterranean, during a monitoring campaign between May and June 2024. Both anthropogenic activities (e.g., vehicular traffic, industrial emissions) and natural events (e.g., wildfires, desert dust transport) were responsible for the high temporal variability of optical, physical, and chemical properties of atmospheric aerosol at the study site. In more detail, the measured Absorption Ångström Exponent (AAE) mean values (in the range 1.0–1.5) indicated a mixture of black carbon and organic or biogenic particles. Correlation analyses between aerosol absorption coefficients and PM mass concentrations highlighted a stronger relationship with EC compared to OC, highlighting the role of EC in the absorption properties of atmospheric aerosols. Chemical characterization through SEM and PIXE identified three aerosol source clusters: anthropogenic (high C concentrations, markers of combustion sources and industrial emissions), desert dust (crustal elements), and marine spray (Na and Cl). IRMS isotopic analysis further confirmed the distinction between anthropogenic and natural aerosol sources, with overlaps observed for marine aerosols influenced by both natural and anthropogenic activities. This work underlines the importance of multi-method procedures in understanding aerosol composition and dynamics, with potential associations for air quality monitoring, climate modeling, and health risk assessments.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100380"},"PeriodicalIF":3.4,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On-board characterization of brake-wear emissions from a heavy-duty vehicle in real-world driving conditions","authors":"Ashok Singh Vishnoi ,&nbsp;Boris Vansevenant ,&nbsp;Asma Beji ,&nbsp;Mathieu Goriaux ,&nbsp;Bernard Guiot ,&nbsp;Yassine Azizi ,&nbsp;Mélanie Messieux ,&nbsp;Patrick Tassel ,&nbsp;Sophie Serindat ,&nbsp;Nicolas Quennet ,&nbsp;Yao Liu","doi":"10.1016/j.aeaoa.2025.100379","DOIUrl":"10.1016/j.aeaoa.2025.100379","url":null,"abstract":"<div><div>Brake wear contributes significantly to non-exhaust emissions, with poorly documented real-world data on ultrafine particles and gaseous emissions, particularly for heavy vehicles. This study focuses on brake wear ultrafine particles emitted by a school bus in real-world driving conditions, through on-board measurements. Some gaseous compounds were also measured. Tests were conducted on a real-world school pick-up route, as well as an in-service-conformity compliant route. A custom-made stainless-steel emission collection system was designed and placed around the front right disc. Particle and gas measurement instruments were sampled directly from the collection system, which was also equipped with temperature sensors. Results show that brake particle emissions range from 4.1 × 10⁷ #/brake/km to 1.7 × 10⁹ #/brake/km, with a bimodal distribution (first mode around 10 nm and second mode around 200 nm). Emissions were analyzed with regard to energy loss during each braking event, showing it can be critical in estimating brake emissions in most cases. In some cases, particle emissions are poorly correlated with energy in the 10 nm mode, which is due to high-intensity and repeated braking episodes. Concentration peaks were also observed for a few volatile organic compounds such as benzene and toluene. Gaseous emission was also observed for CO, CO₂, CH₄, NH₃, NOx, and SO₂.</div></div><div><h3>Glossary</h3><div>Particle collection system, VOCs, high-intensity braking</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100379"},"PeriodicalIF":3.4,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Volatility of secondary organic aerosol and sulphate particles formed in ship engine emission","authors":"Oskari Kangasniemi ,&nbsp;Pauli Simonen ,&nbsp;Panu Karjalainen ,&nbsp;Luis M.F. Barreira ,&nbsp;Jana Moldanová ,&nbsp;Hilkka Timonen ,&nbsp;Barbara D’Anna ,&nbsp;Jorma Keskinen ,&nbsp;Miikka Dal Maso","doi":"10.1016/j.aeaoa.2025.100376","DOIUrl":"10.1016/j.aeaoa.2025.100376","url":null,"abstract":"<div><div>The secondary organic aerosol formation potential of a ship engine emission is assumed to be significant since ship engines are known to emit large amounts semi- and intermediate volatility organic compounds capable of forming secondary organic mass in the atmosphere. However, this is poorly studied in real-world conditions. Here, oxidation reactor was used to simulate atmospheric aging of an exhaust emission aboard a ship in real-world conditions. The samples were also heat-treated to gain information on the volatility of the aged emission. Genetic optimization algorithm was combined with a volatility model to study the volatility distribution of the emission and partitioning of the emission was calculated in different dilution scenarios. Aging of the ship exhaust emission was seen to produce significant amounts of secondary organic mass and quite volatile particle phase sulphate. Most of the secondary organic aerosol was in semi- and intermediate volatility range. This volatility range in particle phase means that care has to be taken when diluting the samples. The gas–particle phase partitioning of volatile material can significantly change the particle phase concentrations in addition to just dilution.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100376"},"PeriodicalIF":3.4,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identifying high-emitting heavy-duty vehicles using remote emission sensing technology","authors":"Miao Tian ,&nbsp;Zhihui Huang ,&nbsp;Shuai Ma ,&nbsp;Mingliang Fu ,&nbsp;Xiaohu Wang ,&nbsp;Jin Liu ,&nbsp;Quanshun Yu ,&nbsp;Jia Wang ,&nbsp;Hang Yin ,&nbsp;Junfang Wang","doi":"10.1016/j.aeaoa.2025.100377","DOIUrl":"10.1016/j.aeaoa.2025.100377","url":null,"abstract":"<div><div>Vehicle emissions are major contributors to air quality issues in many areas of the world. Policymakers are actively exploring new technologies for monitoring vehicle emissions on roads, and remote emission sensing (RES) is a promising approach. However, it is mostly used to evaluate the fleet average emission characters. In this study, we evaluated the accuracy of RES for a single measurement and its ability to identify high-emitting vehicles by conducting concurrent tests with another real-world methods, i.e., using portable emissions measurement system (PEMS) in a test field, as well as city demonstration tests. It was found that the relative errors of single RES measurements decreased from an average of 212.42% to 24.68% when the <span><math><mrow><mi>N</mi><mi>O</mi></mrow></math></span> emission factors exceeded 5 g/kg fuel. The China VI high-emitting diesel vehicles identified by RES <span><math><mrow><mi>N</mi><mi>O</mi></mrow></math></span> measurements were also found to release severe <span><math><mrow><mi>N</mi><mi>O</mi><mi>x</mi></mrow></math></span> emissions based on their on-board diagnostics (OBD) data. This study demonstrates that RES is a suitable tool for detecting high-emitting heavy-duty vehicles with acceptable uncertainty, and provides specific criteria for improving the accuracy of RES data. Additionally, it presents a method to utilize OBD data for identifying high-emitters.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100377"},"PeriodicalIF":3.4,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Severe health risks from ambient volatile organic compounds (VOCs) in a Central Asian city: Source attribution and probabilistic risk assessment","authors":"Alisher Alibekov ,&nbsp;Yingkar Bahetnur ,&nbsp;Kadisha Yessenbayeva ,&nbsp;Nassiba Baimatova ,&nbsp;Woojin Lee","doi":"10.1016/j.aeaoa.2025.100378","DOIUrl":"10.1016/j.aeaoa.2025.100378","url":null,"abstract":"<div><div>Volatile organic compounds (VOCs) significantly contribute to ambient air pollution and pose serious health threats, particularly in rapidly urbanizing regions. This study comprehensively assessed ambient VOC concentrations, identified potential emission sources, and conducted a stochastic human health risk assessment in Almaty, Kazakhstan – a metropolitan Central Asian city characterized by intense traffic, extensive coal combustion, and frequent temperature inversions. Ambient air samples were collected seasonally at multiple elevation points across the city and analyzed for 23 VOC species. Their concentrations were notably elevated during the heating season, especially in the lower city, with benzene, toluene, ethylbenzene, xylenes (BTEX), and naphthalene exhibiting alarming levels compared to other urban settings worldwide. Principal component and BTEX ratio analyses identified coal combustion, vehicle emissions, and industrial activities as the primary VOC sources, with persistent impacts observed even during non-heating seasons due to pollutant resuspension and revolatilization. The stochastic health risk assessment revealed median non-carcinogenic hazard indices generally within acceptable limits but highlighted substantial exceedances (HI &gt; 1) at the 95th percentile, driven mainly by benzene and naphthalene. Carcinogenic risks consistently exceeded acceptable thresholds (10⁻⁶), with benzene being the predominant contributor, which raised urgent public health concerns. Almaty's population faces significantly higher cancer risks than North American and European cities, highlighting the critical need for targeted regulatory measures to mitigate VOC emissions and protect public health.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100378"},"PeriodicalIF":3.4,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145222168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From real-driving emissions to urban air quality: composition of aged PM from modern diesel, gasoline, and CNG fueled cars and plug-in hybrid electric vehicles","authors":"Leïla Simon ,&nbsp;Luis Barreira ,&nbsp;Katariina Kylämäki ,&nbsp;Sanna Saarikoski ,&nbsp;Minna Aurela ,&nbsp;Delun Li ,&nbsp;Anssi Järvinen ,&nbsp;Hannu Kuutti ,&nbsp;Wojciech Honkisz ,&nbsp;Milja Jäppi ,&nbsp;Laura Salo ,&nbsp;Matti Rissanen ,&nbsp;Tereza Červená ,&nbsp;Michal Vojtíšek ,&nbsp;Jan Topinka ,&nbsp;Piotr Bielaczyc ,&nbsp;Topi Rönkkö ,&nbsp;Päivi Aakko-Saksa ,&nbsp;Hilkka Timonen","doi":"10.1016/j.aeaoa.2025.100375","DOIUrl":"10.1016/j.aeaoa.2025.100375","url":null,"abstract":"<div><div>Secondary aerosol emissions from vehicle exhaust often surpass primary particle emissions, yet they are not currently regulated, as they remain difficult to constrain. Here we investigate the factors driving the formation and chemical composition of secondary aerosol from light-duty vehicle exhaust emissions, focusing on the most recent Euro emission standard (Euro 6d), and including hybrid and natural gas cars.</div><div>Seven modern cars were driven through a real-driving emission simulation cycle in a chassis dynamometer. The exhaust emissions were aged in a PAM chamber and their chemical and physical properties measured with an aerosol mass spectrometer and state-of-the-art instrumentation.</div><div>Results indicate that secondary aerosol emissions surpassed fresh aerosol emissions for all cars, except for old Euro 4 diesel. While on average, Euro 6d gasoline and diesel cars aged PM emissions were about 90 % lower than emissions from older cars, their cold start emissions were still significant. Hybrid cars also emitted considerably when switching to combustion engine, which, depending on the length and style of the driving, could be comparable to non-hybrid vehicles emissions. Aged organic aerosol was dominated by oxidized compounds typical of ambient secondary organic aerosol, with unique compositions across vehicle types and fuels. Notably, the CNG vehicle emitted hydrocarbon-like organics, likely originating from less reactive species from lubricant oil, and the Euro 4 diesel exhibited organic nitrate formation, an underreported component in vehicle exhaust with atmospheric implications. Secondary aerosol and its precursors should be regulated and considered in reduction technologies, to best mitigate atmospheric PM in urban traffic-influenced areas.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100375"},"PeriodicalIF":3.4,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Future air quality and human health benefits of net-zero CO2 emissions pathway in China","authors":"Yuhang Zhao ,&nbsp;Yun Shu ,&nbsp;Hong Sun ,&nbsp;Shaohui Zhang ,&nbsp;Yinhe Deng","doi":"10.1016/j.aeaoa.2025.100374","DOIUrl":"10.1016/j.aeaoa.2025.100374","url":null,"abstract":"<div><div>While growing attention has been paid to the co-benefits of climate policies, existing research often lacks granularity in evaluating diverse low-carbon transition strategies and their effects on air pollution and public health, particularly within the context of China's rapidly aging demographic. Here, we assess the PM_2.5 air quality and health co-benefits of a net-zero CO₂ emissions (NZE) pathway aligned with the 1.5 °C global climate target by integrating the Greenhouse Gas-Air Pollution Interactions and Synergies model with updated exposure-response relationships. Compared with China's initial nationally determined contribution scenario – peaking CO₂ emissions around 2030, the NZE pathway reduces SO₂, NO_x and PM_2.5 emissions by roughly 3900 kt, 4500 kt and 770 kt, respectively, by 2050. These reductions lower national population-weighted PM_2.5 concentrations to 18.9 μg/m³, preventing approximately 260,000 premature deaths annually. Guangdong, Shandong, Henan, Sichuan, Jiangsu, and Hubei provinces account for 44 % of the avoided deaths, highlighting significant spatial disparities. Despite these improvements, PM_2.5-related mortality reductions plateau after 2035, suggesting that climate policy alone may not fully offset health risks from population aging and residual pollution. Nationally, the marginal health benefits of CO₂ abatement rise over time, reaching 77 avoided deaths per million tons of CO₂ reduced by 2050, with particularly high values in Beijing and Hainan. The coefficient of variation for avoided PM_2.5-related premature deaths per unit CO₂ abatement rises from 1.12 in 2035 to 1.60 in 2050, indicating growing regional inequality. Our findings demonstrate that ambitious decarbonization delivers pronounced air quality and public health benefits while emphasizing the need for regionally tailored policies to ensure equitable outcomes.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100374"},"PeriodicalIF":3.4,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145120577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of ambient PM2.5 chemical components in Southern California using machine learning","authors":"Jiani Yang ,&nbsp;Sina Hasheminassab ,&nbsp;Meredith Franklin ,&nbsp;Antong Zhang ,&nbsp;David J. Diner ,&nbsp;Joseph Pinto ,&nbsp;Yuk L. Yung","doi":"10.1016/j.aeaoa.2025.100372","DOIUrl":"10.1016/j.aeaoa.2025.100372","url":null,"abstract":"<div><div>Fine particulate matter (PM_2.5, particulate matter with an aerodynamic diameter ≤2.5 μm) poses major public health and environmental risks, yet the toxicity of its chemical components remains poorly understood due to limited chemical speciation data. In this study we apply an extreme gradient boosting (XGBoost) machine learning framework to predict key PM_2.5 components including organic carbon, elemental carbon, nitrate, sulfate, ammonium, and metals, using readily available predictors: total PM_2.5 mass concentrations, meteorological variables, trace gas measurements, and indicators of exceptional events (e.g., wildfires, fireworks). Leveraging a decade of data from two monitoring sites in Southern California (Los Angeles and Rubidoux), the models achieved strong predictive performance, particularly for nitrate, ammonium, and elemental carbon. Among the most influential predictors across components were total PM_2.5 mass, relative humidity, and boundary layer height. This approach has promise for enhancing satellite remote sensing applications, improving chemical transport model inputs, and generating cost-effective estimates of PM_2.5 components during sampling gaps and in regions lacking frequent monitoring. Further research is needed to assess the generalizability of this framework across diverse geographic and climatic settings.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100372"},"PeriodicalIF":3.4,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Where particulates matter: High-rise construction emissions of PM2.5, PM10, BC, and UFP in Dutch cities","authors":"Gabriel Aranda Morales ,&nbsp;Abhiramini M. Rajiv ,&nbsp;Titus Venverloo ,&nbsp;Juliane L. Fry","doi":"10.1016/j.aeaoa.2025.100373","DOIUrl":"10.1016/j.aeaoa.2025.100373","url":null,"abstract":"<div><div>Construction sites are major sources of particulate matter pollution to cities, with heavy diesel equipment producing ultrafine particulate matter (UFP), black carbon (BC), and contributing (alongside earth-moving activities) to emissions of fine (PM_2.5) and coarse (PM₁₀) dust. These air pollutants are hazardous to the health of those working or living within their plumes. Hence, in this study we characterize the short-term pollutant concentrations at three construction sites in the Netherlands. We measured concentrations of four pollutants at three early-stage high-rise construction sites in Rotterdam and Amsterdam. We find that among the pollutants measured, UFP number concentrations are most strongly correlated with construction activities, with construction site concentrations at high levels of activity ∼20,000 # cm⁻³, while concentrations during periods without construction activity are &lt;5000 # cm⁻³. Although we can attribute concentration peaks to specific pieces of construction equipment, there were no strong correlations between UFPs and the measured concentrations of PM_2.5 and PM₁₀, as these latter particles have different sources in construction sites (e.g. earthmoving equipment) and in urban settings, as well as longer atmospheric lifetimes. At a relatively more isolated site with one major piece of diesel equipment, we do observe a strong correlation between UFP and BC (R = 0.62), suggesting that such measurements can be used to obtain emissions ratios. As new regulatory standards are being developed for health-hazardous UFP, knowledge of their number concentrations at and near construction sites will be crucial to developing source apportionments and dispersion modeling. We recommend increased measurement of UFP at construction sites, including the use of wearable monitors, to better understand exposure, and creating incentives to shift from diesel to electrical equipment wherever possible.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100373"},"PeriodicalIF":3.4,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145269214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of different ammonia emission reduction strategies from livestock farming on ambient ammonia concentrations in nature areas: a series of scenario analyses","authors":"Demi van Wijk ,&nbsp;Ceder R. Raben ,&nbsp;Hans J. Erbrink ,&nbsp;Dick J.J. Heederik ,&nbsp;Wietske Dohmen","doi":"10.1016/j.aeaoa.2025.100370","DOIUrl":"10.1016/j.aeaoa.2025.100370","url":null,"abstract":"<div><div>Excessive nitrogen deposition is a major problem in nature areas, causing soil acidification and eutrophication, which reduces biodiversity. In the Netherlands, most nitrogen originates from ammonia emissions related to agriculture. This study investigates how various ammonia emission reduction strategies affect spatial patterns of livestock-related ambient ammonia levels, focusing on nature areas near a livestock-dense region. The aim is to provide insights into effects of interventions on environmental exposure levels and efficiency of mitigation strategies. Using dispersion modeling, annual average patterns of ambient ammonia levels were estimated per scenario, considering emissions from approximately 4500 farms. Results indicate that scenarios involving significant reductions in ammonia emissions (54–86 %), achieved through technical or management modifications or farm removal, result in substantial reductions (62–87 %) in ambient ammonia levels within nature areas. Targeted strategies aimed at specific sectors that contribute most to ammonia levels in nature areas achieved relatively modest absolute reductions (8–13 %) but generally higher efficiency compared to more generic approaches. Scenario efficiency, defined as the ratio between emission/concentration reduction, varied considerably from 0.5 to 1.3. This variations underscores the importance of assessing spatial ammonia patterns rather than focusing and relying solely on emission reduction expressed in terms of total mass. The efficiency of reduction strategies depends on the geographical distribution of (sector-specific) farms near nature areas, and emission height from these farms. Therefore, combined strategies explicitly targeting these factors, such as integrating spatially focused measures (e.g., zoning) with generic emission reductions, are expected most effective in reducing ammonia concentrations in nature areas.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"28 ","pages":"Article 100370"},"PeriodicalIF":3.4,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145098797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}