Atmospheric Environment: X最新文献

{"title":"The effect of air purifiers in improving classroom air quality in a primary school in Rwanda, East-Central Africa","authors":"Egide Kalisa,&nbsp;Ruiming Han","doi":"10.1016/j.aeaoa.2026.100503","DOIUrl":"10.1016/j.aeaoa.2026.100503","url":null,"abstract":"<div><div>Air pollution poses a severe public health challenge in Africa, where ambient particulate matter (PM) concentrations often far exceed World Health Organization (WHO) guidelines. Children are particularly vulnerable, spending long hours in poorly ventilated classrooms, which are often poorly constructed and designed, and inadequately maintained, and where indoor air quality (IAQ) is rarely monitored or improved. This study provides one of the first experimental evaluations of air purifiers (APs) in an African school environment in Rwanda. Minute-level measurements of PM₁, PM_2.5, and PM₁₀ were collected under two conditions (with and without AP operation) and classified into learning hours (LH) and non-learning hours (non-LH). Wilcoxon rank-sum tests and rank-biserial correlations were used to assess the effects of APs. AP use significantly lowered mean PM concentrations throughout the day (5.16% for PM₁, 12.27% for PM_2.5, 11.58% for PM₁₀). The amplification of the diurnal PM decline by APs during learning hours led to substantial reductions (29.79% for PM₁, 33.12% for PM_2.5, and 34.31% for PM₁₀), with significantly larger effect sizes compared to the no-AP condition. APs also accelerated PM_2.5 and PM₁₀ declines to below WHO Interim Target-1 (IT-1) thresholds (35 μg/m³ and 70 μg/m³) within 1.96 and 1.26 h, respectively. These findings provide robust evidence that APs can rapidly and effectively improve IAQ in African schools, offering a feasible intervention to safeguard schoolchildren's health and support healthier learning environments.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100503"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148770967","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":"Hybrid deep learning models for multivariate time-series forecasting of air quality index toward urban sustainability and public health","authors":"Anirban Tarafdar,&nbsp;Rama Seetha Maha Lakshmi Patibandla,&nbsp;Sreeji Sreekumar,&nbsp;Dinesh Kumar Kamalanathan,&nbsp;Gururama Senthilvel Pandiarajan,&nbsp;Dragan Pamucar,&nbsp;Vladimir Simic","doi":"10.1016/j.aeaoa.2026.100501","DOIUrl":"10.1016/j.aeaoa.2026.100501","url":null,"abstract":"<div><div>Escalating air pollution and the limitations of conventional forecasting approaches necessitate advanced models for accurate Air Quality Index (AQI) prediction. This study proposes four hybrid deep learning architectures—Model-1: Hybrid Convolutional Neural Network–Long Short-Term Memory (CNN–LSTM), Model-2: Hybrid LSTM– Deep Neural Network (DNN), Model-3: Hybrid GRU–CNN, and Model-4: Hybrid Conv1D–DNN, that integrate convolutional feature extraction, recurrent temporal modeling, dense representation learning, and attention mechanisms to capture complex temporal dependencies and nonlinear interactions among multiple pollutant and meteorological variables. The four-year daily data from Delhi, consisting of major pollutants such as PM_2.5, PM₁₀, NO, NOx, CO, benzene, and meteorological variables like ambient temperature, solar radiation, and barometric pressure, is employed. Optimized models have been developed by considering different loss functions and learning rates. Low prediction error (RMSE ≈ 36.29) and high correlation (R ≈ 0.9) have been achieved. Model-1 has shown superior performance compared to other models. Significant reduction in error has been observed. The performance of the model has been tested for different seasons, showing robustness in high variability during winter. The performance of the model has also been tested on different city data, such as Ghaziabad and Faridabad. Although the accuracy of the model can be increased by considering more complex models, the results have shown a good trade-off in accuracy and complexity, thus establishing the robustness of the framework. Moreover, accurate AQI forecasting can support public health by enabling timely air quality warnings and informed environmental decision-making.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100501"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148769921","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":"A framework for reproducing field-representative shear in portable wind tunnels used for odour emission measurements","authors":"Pâmela Rossoni Lima,&nbsp;Igor Braga de Paula,&nbsp;Bruno Furieri,&nbsp;Neyval Costa Reis Jr.,&nbsp;Luis Fernando Alzuguir Azevedo,&nbsp;Jane Meri Santos","doi":"10.1016/j.aeaoa.2026.100509","DOIUrl":"10.1016/j.aeaoa.2026.100509","url":null,"abstract":"<div><div>Portable wind tunnels (PWTs) offer advantages over commonly used devices for measuring odorous gas emissions from passive liquid surfaces, such as wastewater stabilization ponds and settling basins, as they enable controlled flow conditions and more representative estimates of emission fluxes. A fundamental and largely unexplored challenge remains: how to prescribe and reproduce field-representative shear conditions within confined portable systems. This is particularly relevant because friction velocity (<span><math><mrow><msup><mi>u</mi><mo>*</mo></msup></mrow></math></span>) plays a dominant role in controlling emission rates, especially for compounds with high gas-phase mass-transfer resistance. PWTs partially enclose the air–liquid interface to quantify emission fluxes while attempting to mimic atmospheric flow conditions. In this study, the internal flow within a PWT is experimentally characterized and modelled to evaluate boundary-layer development and friction velocity. High-resolution Particle Image Velocimetry measurements were conducted under a range of operating conditions. Results show that friction velocity can be predicted using boundary-layer theory. At low flow rates (mean velocities 0.12–0.61 m s⁻¹), consistent with previous studies, the flow remains laminar and is well described by a modified Blasius solution. At moderate flow rates (1.92–2.27 m s⁻¹), the flow is turbulent, with <span><math><mrow><msup><mi>u</mi><mo>*</mo></msup></mrow></math></span> values comparable to field conditions, and the boundary layer is represented by an adjusted turbulent power-law profile. A key outcome is the development of predictive relationships enabling direct prescription of friction velocity through operating flow rate. This work bridges atmospheric boundary-layer flows and PWT conditions, supporting ongoing discussions on the standardization of PWTs for field odour emission measurements and providing a framework for physically based, reproducible emission studies.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100509"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148934997","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":"Aerosol dispersion of state-of-art ventilation concepts in passenger trains—A comparative study","authors":"Michael Mommert,&nbsp;André Volkmann,&nbsp;Felix Werner,&nbsp;Daniel Schmeling","doi":"10.1016/j.aeaoa.2026.100487","DOIUrl":"10.1016/j.aeaoa.2026.100487","url":null,"abstract":"<div><div>We report on an experimental study regarding the performance of state-of-the-art ventilation systems with different inlet positions with respect to the aerosol spread. For that, the spatial distribution of aerosol exposure was determined for six different source locations in a generic passenger compartment. This allowed us to evaluate the different concepts in terms of parameters such as contaminant removal efficiency, the number of seats above a certain threshold or the mean particle concentration in the breathing zone of the passengers. The results revealed strong differences in the local particle concentrations depending on the source position. Further, it was found that two ceiling-based concepts, microjet ceiling and ceiling mounted slot diffusers aimed at the passengers, have significant advantages over the other concepts, especially when it comes to the number of seats with aerosol exposures above certain thresholds. Yet, which concept is optimal still depends on the chosen threshold. The contaminant removal efficiency fluctuates only weakly around 0.5 for the different concepts, revealing mixing-ventilation principles for all concepts.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100487"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148737389","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":"Comprehensive source apportionment of PM2.5-bound water-soluble inorganic ions in Dhaka: A combined PCA and PMF approach","authors":"Azharul Alam Atik,&nbsp;Jannatul Nayem,&nbsp;Md Naeem Islam,&nbsp;Md Samsul Hoque Dany,&nbsp;Farhana Jahan,&nbsp;Shizhen Zhao,&nbsp;Gan Zhang,&nbsp;Ahsan Habib","doi":"10.1016/j.aeaoa.2026.100505","DOIUrl":"10.1016/j.aeaoa.2026.100505","url":null,"abstract":"<div><div>Air pollution has emerged as a serious environmental problem in Dhaka that is always rated as one of the most polluted cities in the world. The research describes the chemical composition and sources of water-soluble inorganic ions in fine particulate matter (PM_2.5) collected from November 2023 to March 2024 at a representative urban rooftop location at Dhaka University and found that major cations, particularly Na⁺, K⁺, Ca²⁺, and anions, such as F⁻, Cl⁻, NO₃⁻, SO₄²⁻, had high pollution levels, greatest in December and January, 11-15 times higher than WHO limits. Source identification integrated Pearson correlation screening and principal component analysis (PCA) used only as an exploratory diagnostic step, and quantitative source apportionment with the EPA PMF 5.0 receptor model. The analysis successfully resolved four distinct sources, including regional secondary aerosol formation, local fluoride-rich industrial emissions, crustal and construction dust, and a mixed marine/biomass-burning influence. These results are corroborated by HYSPLIT backward trajectory analysis that revealed that there were strong transboundary inflows in winter of the northwest and west, providing new scientific data to the global scientific knowledge on wintertime PM_2.5 dynamics and air quality management in Bangladesh. To our knowledge, this study is one of the most comprehensive continuous records to date for both major cations and anions over a five-month period in Dhaka and is one of the first to apply PCA, PMF and HYSPLIT analyses simultaneously on a Dhaka WSII dataset, identifying a local source of fluoride.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100505"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148951541","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":"Improving dust simulation over the Taklimakan Desert through refinement of wind profile parameters in the Revised-MM5 scheme","authors":"Yisilamu Wulayin,&nbsp;Wen Huo,&nbsp;Ali Mamtimin,&nbsp;Fan Yang,&nbsp;Huoqing Li,&nbsp;Junjian Liu,&nbsp;Ailiyaer Aihaiti,&nbsp;Chenxiang Ju,&nbsp;Yu Wang,&nbsp;Meiqi Song,&nbsp;Jian Peng,&nbsp;Haotong Liu","doi":"10.1016/j.aeaoa.2026.100499","DOIUrl":"10.1016/j.aeaoa.2026.100499","url":null,"abstract":"<div><div>The Taklimakan Desert, the world's second-largest shifting-sand desert, is a major dust source for northwestern China and East Asia, and its emissions contribute substantially to the global dust cycle. Therefore, improving dust forecasts over this region is essential. To address limited applicability of the wind-profile functions in the Revised MM5 surface-layer scheme over the Taklimakan Desert, we recalibrated the scheme's stability parameters using turbulence and gradient measurements from the Tazhong station, and evaluated the impacts through sensitivity experiments. The estimated von Kármán constant (k) averages 0.41, close to the canonical value (0.40). The recalibrated stability parameters (γ_m = 19.0 for unstable conditions; β_m = 5.8 for stable conditions) fall within expected theoretical ranges. Using the revised parameters improves the correlation coefficient(R) of 10-m wind speed at 62% of stations, while reducing the mean absolute error (MAE) and root mean square error (RMSE) at 76% and 71% of stations, respectively, with particularly notable improvements during the morning and afternoon transition periods during March–May 2020. For dust concentrations, PM10 MAE and RMSE decrease by 1–6.5% across all stations. For PM2.5, the R increases by 1–4%, and MAE and RMSE decrease by 1–6.8%. Aerosol optical depth (AOD) decreases by 0.1–0.2 over the northwestern and eastern parts of the desert, effectively reducing the model's systematic high bias in dust simulation.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100499"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148854357","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":"Air pollution exposure inequality across U.S. income and racial groups, 2000–2023: A hybrid monitor–satellite analysis with two new shape diagnostics","authors":"Tom Regpala,&nbsp;Eric Palafox,&nbsp;Anjana Yatawara","doi":"10.1016/j.aeaoa.2026.100492","DOIUrl":"10.1016/j.aeaoa.2026.100492","url":null,"abstract":"<div><div>Estimates of exposure inequality depend both on where air pollution is measured and on how inequality is summarised from those measurements. Environmental-justice surveillance typically compresses a pollutant’s socioeconomic gradient into one regression slope, the slope index of inequality (SII), defined as the population-weighted slope of group-mean concentration on income rank. A single slope assumes that the concentration–rank profile is a straight line and that exposure and income move together within every income group. The SII still returns a number when either assumption fails, but it no longer flags the misfit. We characterise county-level exposure inequality across the contiguous United States for four criteria pollutants (PM_2.5, NO₂, O₃, SO₂) over 2000–2023 (up to 44 states). We add two dimensionless shape diagnostics to the standard slope. The Middle-Group Residual (MGR) is the signed departure of the middle-income stratum from the SII line, and the Within-Stratum Slope Heterogeneity (WSSH) is the spread of within-stratum exposure–income correlations. PM_2.5 exposure uses a population-weighted hybrid of regulatory monitors and satellite-derived concentrations; the other pollutants use the monitor network. The mean income-stratified relative index of inequality (RII) is <span><math><mrow><mo>−</mo><mn>0.048</mn></mrow></math></span> (PM_2.5), <span><math><mrow><mo>+</mo><mn>0.278</mn></mrow></math></span> (NO₂), <span><math><mrow><mo>−</mo><mn>0.018</mn></mrow></math></span> (O₃), and <span><math><mrow><mo>+</mo><mn>0.147</mn></mrow></math></span> (SO₂). The PM_2.5 gradient reverses sign between the monitor-equipped county subset (RII <span><math><mrow><mo>+</mo><mn>0.074</mn></mrow></math></span>, lower-income more exposed) and the population-representative full-county sample (RII <span><math><mrow><mo>−</mo><mn>0.048</mn></mrow></math></span>). This reversal directly reflects the siting of the monitoring network. Non-linear profiles dominate; <span><math><mrow><mo>|</mo><mi>MGR</mi><mo>|</mo></mrow></math></span> exceeds 0.02 in 50%–92% of state-years and rises monotonically at finer partitions. The SO₂ gradient reversed direction over the period (HAC <span><math><mrow><mi>p</mi><mo>=</mo><mn>0.003</mn></mrow></math></span>). Its remaining burden along the racial-composition axis falls on lower-income but predominantly White rural counties, so the income and racial axes diverge. A single slope cannot reveal this divergence. Across these four pollutants, the slope alone is therefore an incomplete summary. Its sign can hinge on which counties host monitors, and its straight-line form fails in most state-years. The MGR and WSSH recover the missing shape and coverage information from the same county data the SII already uses.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100492"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148642226","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":"Comparative assessment of emissions and performance of biomass cookstove technologies relevant to Nepal under controlled laboratory conditions","authors":"Juho Louhisalmi,&nbsp;Henna Rinta-Kiikka,&nbsp;Narayan Babu Dhital,&nbsp;Antti Oksala,&nbsp;Antti Karjalainen,&nbsp;Hanna Koponen,&nbsp;Marko Hyttinen,&nbsp;Sunil Prasad Lohani,&nbsp;Rejina Maskey Byanju,&nbsp;Olli Sippula,&nbsp;Jarkko Tissari","doi":"10.1016/j.aeaoa.2026.100512","DOIUrl":"10.1016/j.aeaoa.2026.100512","url":null,"abstract":"<div><div>Traditional biomass cooking remains a major source of household air pollution and climate-relevant emissions in South Asia, yet comparable emission data for commonly used cookstove technologies remain limited. This study evaluated the performance and emissions of eight biomass cookstove configurations representing gasifier, rocket, chimney, and traditional stove designs. Laboratory-based Water Boiling Tests (WBT) were conducted in Finland under controlled conditions using a partial-flow dilution system for particle sampling. Emissions were characterized with real-time gas analysers and extensive aerosol measurements, including fine particle mass (PM_2.5), particle number (PN), alveolar-region lung-deposited surface area (ALV-LDSA), organic (OC) and elemental carbon (EC), equivalent black carbon (eBC), and polycyclic aromatic hydrocarbons (PAHs). Emission factors were calculated using WBT, carbon mass balance (CMB), and Finnish emission measurement standard -based methods to assess methodological consistency. The WBT and CMB methods produced largely consistent emission factors, indicating that simple CO₂- and CO-based approaches provide reliable estimates for the main carbonaceous emissions. Stove performance and emissions varied substantially between technologies. The forced-draft gasifier showed the best performance and lowest emissions, whereas the chimney stove exhibited poor performance and high gaseous and particulate emissions, despite being classified as an improved stove. Phase-resolved analysis showed that refuelling periods produced transient emission peaks, especially for fan-assisted stoves. Tests without a cooking pot resulted in 40−96% lower emissions, demonstrating that stove–pot interaction strongly affected combustion conditions and emission formation. These findings underscore the need for integrated evaluation across performance indicators and multiple emission metrics to identify low-emission cooking technologies.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100512"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148935040","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":"A decade of traffic supersite measurements: Trends in air pollution, compliance with guidelines, and source attribution","authors":"Hilkka Timonen,&nbsp;Elli Suhonen,&nbsp;Teemu Lepistö,&nbsp;Kimmo Teinilä,&nbsp;Minna Aurela,&nbsp;Laura Salo,&nbsp;Luis M.F. Barreira,&nbsp;Anu Kousa,&nbsp;Liisa Pirjola,&nbsp;Harri Portin,&nbsp;Anssi Julkunen,&nbsp;Tatu Martinmäki,&nbsp;Janne Lampilahti,&nbsp;Leena Järvi,&nbsp;Heidi Hellén,&nbsp;Hermanni Aaltonen,&nbsp;Eija Asmi,&nbsp;Tuukka Petäjä,&nbsp;Miikka Dal Maso,&nbsp;Markus Sillanpää,&nbsp;Jarkko V. Niemi","doi":"10.1016/j.aeaoa.2026.100511","DOIUrl":"10.1016/j.aeaoa.2026.100511","url":null,"abstract":"<div><div>This article presents the results of long-term air quality measurements (2015–2024) from the Helsinki Traffic Supersite, including gaseous compounds (NO, NO₂, CO, CO₂, O₃), particulate matter (PM_2.5, PM₁₀, particle number (PN) and size distribution), chemical composition of PM (black carbon (BC), organic aerosol (OA), inorganic species), lung-deposited surface area (LDSA), polycyclic aromatic hydrocarbons, volatile organic compounds (VOC), as well as road surface conditions and meteorology. In addition to the long-term observations, large number of targeted short-term measurement campaigns were conducted to investigate emerging phenomena, to further develop supersite measurements and gain new information about sources impacting air quality.</div><div>The observed air quality improvements at the Traffic Supersite were driven by declining traffic exhaust concentrations (NO_x (−8.0%/yr), BC (−7.1%/yr), PN (−3.7%/yr), and anthropogenic VOCs (−3.1 to −8.9%/yr)). The observed emission factors (g/kg_fuel) also decreased for NO_x (−7.6%/yr), BC (−7.5%/yr), and PN (−4.1%/yr), reflecting fleet renewal. The observed rate of decrease in PN concentration was lower than that of other parameters, particularly in the smallest size classes (&lt;30 nm). Organic aerosol analysis showed that traffic hydrocarbon tracers (m/z 57) declined faster (−7.9%/yr) than total OA and oxidized OA (m/z 44), which are linked to secondary formation and long-range transport. Long-term results indicate that compliance with the upcoming EU Air Quality Directive limit values for 2030 is already largely achievable, with the most challenging aspect being the exceedances of the PM₁₀ daily limit due to road dust events. However, achieving the EU Zero Pollution target for 2050 remains challenging, and the WHO guideline values for PM₁₀, PM_2.₅ and NO₂ continue to be exceeded. These unique findings highlight the importance of comprehensive, long-term supersite measurements for understanding pollutant sources and trends, and for supporting urban planning and policy development.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100511"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148935041","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":"Anthropogenic aerosol composition modulates summer precipitation in East Asia","authors":"Di Chen,&nbsp;Xinyan Lyu,&nbsp;Minghu Ding,&nbsp;Qizhen Sun","doi":"10.1016/j.aeaoa.2026.100488","DOIUrl":"10.1016/j.aeaoa.2026.100488","url":null,"abstract":"<div><div>East Asia critically relies on precipitation for freshwater, yet faces severe anthropogenic aerosol pollution. Understanding whether and how aerosols regulate regional rainfall is therefore essential. Using decade-long coupled chemistry–meteorology simulations, we quantify the impacts of total anthropogenic aerosols and their major components on precipitation and disentangle the underlying mechanisms. Aerosols suppress rainfall through two coupled pathways. First, reduced surface solar radiation cools the lower troposphere and stabilizes the boundary layer, weakening convective available potential energy. This triggers anomalous mid-tropospheric subsidence and a weakened low-level monsoon circulation, effectively throttling moisture supply to East Asia. Second, aerosol–cloud interactions enhance low-level clouds and suppress high-level clouds in the subtropics. Quantitatively, indirect cloud-mediated effects dominate, producing an ∼34% precipitation reduction relative to the clean-air baseline, while direct radiative effects contribute a ∼30% decrease. The precipitation response is highly sensitive to aerosol composition: sulfate and organic aerosols drive most rainfall suppression through cloud redistribution, whereas black carbon partly offsets this effect via atmospheric heating and enhanced convection. These findings highlight the critical role of aerosol composition in regulating precipitation and freshwater availability across East Asia.</div></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"31 ","pages":"Article 100488"},"PeriodicalIF":3.4,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148737388","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}