Atmospheric Environment最新文献

{"title":"Strategic reductions in residential emissions: A perspective through enhanced GAINS modeling","authors":"Sahir Azmi ,&nbsp;Adnan Mateen Qadri ,&nbsp;Tarique Ahmad ,&nbsp;Afzal Husain Khan ,&nbsp;Md Faruque Ahmad","doi":"10.1016/j.atmosenv.2025.121502","DOIUrl":"10.1016/j.atmosenv.2025.121502","url":null,"abstract":"<div><div>This study employs the Greenhouse gas – Air pollution Interactions and Synergies (GAINS) model to analyse air pollution in Bathinda, Delhi, and Kanpur within the Indo-Gangetic Plain of South Asia, contrasting a Business-As-Usual (BAU) scenario with a Residential (RES) scenario that advocates for cleaner household energy use. It highlights the issue of ambient PM_2.5 levels exceeding India's National Ambient Air Quality Standards, a common challenge in urban areas worldwide. The RES scenario's transition to cleaner fuels, including Liquefied Petroleum Gas, biogas, and renewable sources, forecasts significant emission reductions: a 26.76 % decrease in PM_2.5 and a 10.67 % reduction in SO₂ emissions. This adjustment leads to a 16.14 % improvement in average PM_2.5 exposure, from 90.62 to 75.99 μg/m³, potentially preventing nearly one-third of premature deaths due to air pollution. By quantitatively evaluating residential emission control strategies and their health impacts using the GAINS model, this study offers a replicable framework for clean air planning in highly polluted regions. The Indo-Gangetic Plain case study provides transferable insights into sustainable energy transitions, supporting global air quality strategies. These findings highlight the critical role of household energy reform, technology adoption, and policy integration in reducing pollution exposure—core principles that can guide international environmental and public health agendas.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"362 ","pages":"Article 121502"},"PeriodicalIF":3.7,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The development of the thermal internal boundary layer and its impact on ozone vertical distribution","authors":"Z.S. Han ,&nbsp;H.N. Liu ,&nbsp;X. Shao ,&nbsp;N. Zhang","doi":"10.1016/j.atmosenv.2025.121499","DOIUrl":"10.1016/j.atmosenv.2025.121499","url":null,"abstract":"<div><div>The evolution of the Thermal Internal Boundary Layer (TIBL) under Sea Breeze Circulation (SBC) plays a crucial role in pollutant dispersion, particularly in coastal urban areas. This study investigates the TIBL height (TIBLH) during a severe O₃ pollution episode in Hangzhou on June 5, 2016, using high-resolution simulations from the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). Traditional parameterizations such as the MK1992 method tend to overestimate TIBLH by neglecting urban heat island (UHI) effects and he inland enhancement of momentum by the SBC. To address these limitations, we develop an improved scheme, HS 2024, which explicitly incorporates both the UHI-driven thermal convection and SBC-induced mechanical turbulence. Compared to MK 1992, HS2024 more accurately captures the diurnal evolution of TIBLH and its modulation of vertical O₃ transport. As the SBC progresses inland, the TIBLH gradually decreases and forms a capping layer that traps pollutants in the lower troposphere, exacerbating near-surface O₃ concentrations. These findings underscore the importance of accounting for both thermal and dynamical processes in TIBLH estimation and provide a more physically grounded framework for air quality prediction in complex coastal cities.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121499"},"PeriodicalIF":3.7,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144911847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time series analysis and prediction of PM2.5 pollution concentration in Igdir province with deep learning models","authors":"Muhammed Kaya,&nbsp;İhsan Ömür Bucak","doi":"10.1016/j.atmosenv.2025.121491","DOIUrl":"10.1016/j.atmosenv.2025.121491","url":null,"abstract":"<div><div>Air pollution is a global problem that causes serious environmental and health problems, especially in regions where industrialization and urbanization are intense. Igdir province, located in the eastern part of Türkiye, is one of the regions where air pollution is intensely observed due to its geographical structure and meteorological characteristics. This study evaluated deep learning models for predicting PM2.5 levels using data from national monitoring networks, meteorological services, and NASA POWER. Preprocessing included interpolation, outlier correction, and min–max normalization. LSTM, GRU, Bi-LSTM, Bi-GRU, CNN-LSTM, and CNN-GRU models were tested across 8, 24, and 72 h windows. The GRU model achieved the best performance in short-term (8 h) predictions with MAE=9.93 and R<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span>=0.944 values. The LSTM model reached the best predictive performance for the 24 h window with MAE=9.65 and R<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span>=0.949, while for the 72 h window, the BiLSTM model outperformed the others. In terms of predicting peak values, the CNN-LSTM model stood out, achieving RMSE=28.16, R<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span>=0.792, and MAE=22.45 in the 8 h window. These findings highlight deep learning’s efficacy for air pollution forecasting and decision support.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121491"},"PeriodicalIF":3.7,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144892204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comprehensive analysis of prevailing weather patterns and high-impact typhoon tracks to reveal where and how tropical cyclone affects regional ozone pollution in the Yangtze River Delta region, China","authors":"Mengzhu Xi ,&nbsp;Yi Luo ,&nbsp;Yichen Li ,&nbsp;Danyang Ma ,&nbsp;Lingyun Feng ,&nbsp;Shuxian Zhang ,&nbsp;Shitong Chen ,&nbsp;Min Xie","doi":"10.1016/j.atmosenv.2025.121498","DOIUrl":"10.1016/j.atmosenv.2025.121498","url":null,"abstract":"<div><div>The Yangtze River Delta (YRD) region is a typical economically developed and densely populated coastal city cluster. During warm seasons, the YRD generally suffers from extreme weather when tropical cyclones (TCs) make landfall. However, the YRD is also affected by severe ozone (O₃) pollution when TCs are not far away. It has been reported that the peripheral flow of TCs is related to the regional O₃ pollution over the YRD. Nevertheless, the tracks and locations of TCs, as well as the mechanisms of their effects, are still unclear. This study tries to reveal how and where TCs cause regional O₃ pollution in the YRD based on a comprehensive analysis of prevailing synoptic weather patterns (SWPs) and high-impact TC tracks. For weather patterns, the NCEP reanalysis data and the Principal Component Analysis in T-mode (PCT) analysis method were adopted to objectively classify the 850 hPa geopotential height field in the YRD from 2018 to 2021. By integrating the air pollution observation data and the meteorological data in the YRD of the same period, a systematic analysis of the O₃ pollution characteristics and their formation mechanism under different SWPs was conducted. Meanwhile, trajectory clustering analysis was conducted on TC track data to investigate the mechanisms of TCs with different paths on O₃ pollution in the YRD. The results indicate that O₃ concentration in the YRD generally peaks in June and September, and regional O₃ pollution usually occurs before TCs land and after TCs dissipate. The SWPs in the YRD can be categorized into seven categories. Among them, SWP3 and SWP4 are SWPs that will be affected by TCs, while SWP6 and SWP7, which have similar circulation situations, are not affected by TCs. TCs are very important weather systems in SWP3 and SWP4. Furthermore, based on O₃ pollution classification under different SWPs and TC track clustering analysis, how TC trajectories and central locations affect regional O₃ pollution over the YRD is revealed. Under SWP3, TCs usually have the northwest-turning track, and cause the highest O₃ pollution levels in the YRD when their centers are located in the area of (130°–135°E, 20°–30°N). Downdrafts caused by western Pacific subtropical high (WPSH) and the peripheral downward airflows of TCs make the air more stagnant over the YRD. The accumulation of air pollutants, as well as more intensive chemical reactions due to higher temperature, are the main cause of regional O₃ pollution. For SWP4, however, TCs generally have the westward track, and regional O₃ pollution in the YRD occurs when TCs are located over the area of (125°–130°E, 10°–16°N) with stronger intensities. More O₃ is transported from inland polluted areas to the YRD due to the peripheral advection airflows of the strong TCs under SWP4. There are fewer downward airflows caused by TCs when","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121498"},"PeriodicalIF":3.7,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144889265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the characteristics and triggering factors of concurrent events of ozone pollution and nocturnal ozone increase in Xinxiang, China","authors":"Huanpeng Wang ,&nbsp;Liya Fan ,&nbsp;Xuejiao Deng ,&nbsp;Haomin Huang ,&nbsp;Daiqi Ye","doi":"10.1016/j.atmosenv.2025.121494","DOIUrl":"10.1016/j.atmosenv.2025.121494","url":null,"abstract":"<div><div>In recent years, the phenomenon of nocturnal ozone increase (NOI) has become increasingly common worldwide. The occurrence of such events can potentially enhance the risk of ozone pollution, but the connection between NOI events and ozone pollution remains poorly understood. Based on ground observations, ERA5 dataset and air quality models (CMAQ and CAMx), this study investigates the characteristics of ozone pollution and NOI concurrent events in Xinxiang, China from 2017 to 2021, and qualitatively and quantitatively analyzes the triggering factors on a typical persistent concurrent event (PCE, June 13–20, 2017). We identify the relationship between summer ozone pollution and NOI events. On ozone pollution days, NOI is more prone to occur (incidence: 46.8 %). At the same time, the occurrence of NOI events tends to cause a higher ozone base in the morning from 04:00 to 10:00 local time (LT, 9.12–16.20 μg m⁻³ higher than that of non-NOI days), promoting the emergence of ozone pollution. During PCE, for all NOI events (12 times) and ozone pollution, vertical diffusion (VDIF) is the primary trigger, followed by regional transport from the latitudinal (north-south) direction (YADV), which is mainly distributed in central and southern Henan (especially Zhengzhou). Additionally, local emissions from industry and transportation also have a significant influence on ozone levels in Xinxiang. This study identifies the characteristics and relationship between NOI events and ozone pollution, and reveals the formation mechanism of PCE, which provides new insights into NOI research and will promote local ozone pollution prevention and control.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121494"},"PeriodicalIF":3.7,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144916728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensitivity analysis of WRF-CMAQ model in predicting PM2.5 and O3 concentration in Peninsular Malaysia: 2019 transboundary burning smoke case study","authors":"Nur Nazmi Liyana Mohd Napi ,&nbsp;Maggie Chel Gee Ooi ,&nbsp;Mohd Talib Latif ,&nbsp;Liew Juneng ,&nbsp;Mohd Shahrul Mohd Nadzir ,&nbsp;Wee Cheah ,&nbsp;Andy Chan ,&nbsp;Li Li","doi":"10.1016/j.atmosenv.2025.121496","DOIUrl":"10.1016/j.atmosenv.2025.121496","url":null,"abstract":"<div><div>The high PM_2.5 concentrations significantly influence the air quality in the Maritime Continent region, especially in Peninsular Malaysia (PMY), which is affected by the annual burning season. However, the 2019 pollution case is unique due to the presence of a positive Indian Ocean dipole (pIOD) with a weak El Niño, which influenced the transport of pollutants toward PMY. This work aims to evaluate the ability of the numerical chemical weather prediction model (WRF-CMAQ) by performing a sensitivity analysis to reproduce the air quality during this event. Two model settings were studied: weather nudging and the burning emission amount of the fire inventory from NCAR (FINN). Three cases were established: 1) WRF-CMAQ_w (without nudging setting and with original fire emission), 2) WRF-CMAQ_n (with nudging setting and with original fire emission), and 3) WRF-CMAQ_a (with nudging setting and adjusted fire emission) to predict the PM_2.5 concentration in PMY during the 2019 transboundary smoke event. The weather (temperature and wind profile) simulation results showed that WRF-CMAQ_a and WRF-CMAQ_n agreed up about 95 % and WRF-CMAQ_w agreed up to 93 % when compared with ground weather stations based on the statistical evaluation of correlation coefficient, bias, and error measures. For air quality, overall, WRF-CMAQ_a (87.23 %) demonstrated better performance compared to WRF-CMAQ_w (62.41 %) and WRF-CMAQ_n (78.72 %) in predicting the ground PM_2.5. However, the diurnal prediction during the transboundary smoke event remains weak. For O₃ concentration, the model performance agreement was quite low for all simulations. However, WRF-CMAQ_a could predict about 44.76 % compared to WRF-CMAQ_n (26.66 %) and WRF-CMAQ_w (41.90 %) in overall model performance, and all simulations managed to capture the diurnal trend of O₃ when compared with ground observation station data. In conclusion, the sensitivity study on the weather and chemical prediction model, especially WRF-CMAQ, could help improve the air quality prediction system in PMY during the recurrence of transboundary smoke events.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"362 ","pages":"Article 121496"},"PeriodicalIF":3.7,"publicationDate":"2025-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145107042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emission characteristics and environmental impacts of carbonyl compounds from construction machinery in China","authors":"Yifei Wang ,&nbsp;Yuan Chen ,&nbsp;Xueqi Qiao ,&nbsp;Jia'nan Cui ,&nbsp;Mei Sun ,&nbsp;Jianbo Zhang","doi":"10.1016/j.atmosenv.2025.121493","DOIUrl":"10.1016/j.atmosenv.2025.121493","url":null,"abstract":"<div><div>Carbonyl compounds play a significant role in atmospheric chemistry, leading to the formation of ozone and secondary organic aerosols. Emissions of carbonyl compounds from construction machinery cannot be ignored. In this study, a total of 37 units of in-use construction machinery were tested using portable emission measurement system under real-world operating conditions. Carbonyl compounds were collected using the O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine derivatization method and analyzed via gas chromatography-mass spectrometry. The composite carbonyl compound emission factors of excavators, forklifts, loaders, road rollers, pile engines and graders were 3.30 ± 1.45 g/kg-fuel, 2.05 ± 0.97 g/kg-fuel, 3.20 ± 1.18 g/kg-fuel, 2.69 ± 1.02 g/kg-fuel, 5.55 ± 2.26 g/kg-fuel and 2.94 ± 1.31 g/kg-fuel, respectively. Pile engines exhibited the highest emission factors during working, whereas the others had the highest emission factors while idling. In addition, the continuous tightening of emission standards has effectively reduced the emissions of carbonyl compounds from construction machinery. The total emissions of carbonyl compounds from five typical construction machinery in China in 2019 were estimated to be 12.1 kt, with corresponding ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) of 82.5 kt and 360.1 t, respectively. Acetaldehyde and formaldehyde were the primary contributors to the total emissions and OFP, while benzaldehyde was the largest contributor to the SOAFP. The contributions of Jiangsu and Zhejiang provinces to total emissions of carbonyl compounds and their corresponding OFP and SOA were much higher than those of other provinces. Our results supplement the limited emission factor data for carbonyl compounds from construction machinery and can aid in improving emission inventories and developing targeted control strategies to enhance air quality.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121493"},"PeriodicalIF":3.7,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144852894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interdecadal feature and mechanism of global dusty weather","authors":"Weiqi Tang ,&nbsp;Yuzhi Liu ,&nbsp;Tongyu Wang ,&nbsp;Dan Li ,&nbsp;Jie Gao ,&nbsp;Ziyuan Tan ,&nbsp;Xuefeng Dong","doi":"10.1016/j.atmosenv.2025.121487","DOIUrl":"10.1016/j.atmosenv.2025.121487","url":null,"abstract":"<div><div>Dusty weather (including dust storms, blowing dust and floating dust) represents a catastrophic weather phenomenon with extensive adverse environmental impacts. However, its natural variability and underlying mechanisms at the global scale remain insufficiently explored in prior research. This study investigates the spatiotemporal distribution characteristics and driving mechanism of global dusty weather using long-term station observations and reanalysis data. Our findings reveal a significant declining trend in dusty weather over the Taklimakan Desert and southwestern Sahara Desert from 1979 to 2023, whereas an increasing trend is observed over the northern Sahara Desert, Arabian Desert and Gobi Desert during the same period. Temporally, global dusty weather activity exhibits a decline from 1979 to 1999, followed by an interdecadal-scale oscillation with cycles of 10–14 years after 1999. The mechanistic analysis demonstrates that Atlantic climate modes—particularly the South Atlantic Subtropical Dipole (SASD) and the North Atlantic Oscillation (NAO)—play a dominant role in modulating the interdecadal variability of dust storms, with correlation coefficients of −0.44 (SASD) and 0.37 (NAO), respectively. Consequently, energy convergence over dust source regions, modulated by the SASD and NAO, stimulates low-pressure troughs and intensified westerlies in the Northern Hemisphere, alongside warm high-pressure systems in the Southern Hemisphere, both of which enhance dust storms. Our results advance the understanding of global dusty weather dynamics and offer valuable insights for future dust storms prediction.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121487"},"PeriodicalIF":3.7,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144858509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Short-term exposure to particulate matter (PM10/2.5) from Varanasi, India led to asthma aggravation and early fibrotic changes in mice model: Insights into its regulation","authors":"Diksha Sharma ,&nbsp;Payal Singh ,&nbsp;Prashant Kumar Chauhan ,&nbsp;Vandana Soni ,&nbsp;Abhay Kumar Singh ,&nbsp;Rashmi Singh","doi":"10.1016/j.atmosenv.2025.121484","DOIUrl":"10.1016/j.atmosenv.2025.121484","url":null,"abstract":"<div><h3>Background</h3><div>Particulate matter (PM10/2.5<strong>)</strong> is a ubiquitous air pollutant with detrimental health impacts where fine particles (PM2.5) are posing serious threats to respiratory health. With potentially worse outcomes, it is silently damaging the lungs of people already suffering from respiratory diseases like asthma. The continuous exposures to poor air quality in recent years raises urgent questions for both, immediate and long-term health impacts. Both PM10/2.5 levels have surpassed the Indian National safety standards raising serious concerns about the environmental and health consequences.</div></div><div><h3>Methodology</h3><div>This study aimed to investigate impact of PM10/2.5 exposures on mice lungs where pathological changes in OVA-induced asthmatic mice lungs were compared with normal mice lungs. BALB/c mice were sensitized with ovalbumin (OVA, i.p), followed by OVA aerosol (1 %OVA) challenge, and later subjected to PM10/2.5 exposures (0.5 mg/kg, i.n) continuously for five consecutive days. Lung samples were assessed for oxidative stress markers (ROS and lipid peroxidation), inflammatory mediators (nitric oxide, histamine, myeloperoxidase, eosinophil peroxidase, IL-6), fibrotic markers (collagen deposition, MMP-9 activity, α-SMA expression), and histopathological changes. Dose-dependent cytotoxicity, oxidative stress induced DNA damage in human alveolar epithelial cells (A549) after PM10/2.5 exposures were thoroughly investigated. Curcumin derived from turmeric (<em>Curcuma longa</em>) is known anti-oxidant and anti-inflammatory molecule, was studied for its therapeutic efficacy on PM-induced asthma aggravations and fibrotic changes.</div></div><div><h3>Key findings</h3><div>Significant lung damage was noted after short-term PM10/2.5 exposures (5 days) with aggravated inflammatory and fibrotic changes in both, normal and asthmatic mice lungs, where PM2.5 exposure was severe. Significant morphological and histopathological changes like lung tissue remodeling, epithelial thickening, and collagen deposition was observed. Enhanced immune cell recruitment, ROS and MDA levels along with significantly decreased key antioxidant enzymes, Superoxide dismutase (SOD) and Catalase, compared to the control group were noted with reduced GSH level. Upregulated expression of NF-kB, a transcription factor after PM10/2.5 exposure was found in normal mice which was heightened in asthmatic mice. Enhanced MMP-9 activity was also confirmed by immunofluorescent detection of Alpha-smooth muscle actin (α-SMA). Curcumin, a plant-derived molecule, significantly mitigated PM2.5 exposed airway inflammation and fibrotic changes in lungs by suppressing NF-κB expression and enhancing Nrf2 level. <em>In vitro</em> studies validated these findings, where dose-dependent decrease in cell viability and increased in ROS level along with apoptotic changes A549 cells were observed after PM exposure. Enhanced IL-6 and PARP-1 expression confirmed ","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121484"},"PeriodicalIF":3.7,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144887183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal variations in PM2.5 levels in Hong Kong induced by eastern and western tropical cyclones","authors":"Shuqing Zeng ,&nbsp;Jung-Eun Chu ,&nbsp;Hung Ming Cheung ,&nbsp;Kanghyun Baek ,&nbsp;Han-Kyoung Kim ,&nbsp;Jun-Hyeok Son","doi":"10.1016/j.atmosenv.2025.121497","DOIUrl":"10.1016/j.atmosenv.2025.121497","url":null,"abstract":"<div><div>Air pollution, particularly PM2.5 (particles smaller than 2.5 μm), is a major environmental issue in densely populated cities like Hong Kong, as these particles can deeply penetrate the respiratory system. It has been known that tropical cyclones (TCs) can cause a significant increase in PM2.5 concentrations when positioned to the east of Hong Kong. However, the seasonal variations in how the proximity of TCs influences PM2.5 levels and aerosol optical properties in Hong Kong remain poorly understood. Using observations from 1999 to 2020, this study demonstrates that the impact of TCs on air pollution in Hong Kong is more pronounced during the summer (June to August) compared to the autumn season (September to November), primarily due to strong subsidence, surface warming, and the transport of fine-mode aerosols by northerly wind driven by eastern TCs. Conversely, western TCs efficiently remove pollutants in summer due to the influx of clean air from southerly winds, but this effect diminishes in autumn when background PM2.5 levels are high and TC-induced subsidence is absent. Further analysis of aerosol properties reveals that eastern (western) TCs tend to increase (decrease) the fine-mode fraction and decrease (increase) the fine-mode Angström exponent during the JJA season, whereas these differences are negligible during the SON season.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121497"},"PeriodicalIF":3.7,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144867441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}