Atmospheric Environment最新文献

{"title":"Unveiling metal-HULIS binding dynamics in cloud water via multispectral 2D-COS: integrating EEM-PARAFAC and FTIR insights","authors":"Xinghui Liu ,&nbsp;Junkai Cui ,&nbsp;Tao Li ,&nbsp;Xinfeng Wang ,&nbsp;Likun Xue ,&nbsp;Rutao Liu ,&nbsp;Yan Wang","doi":"10.1016/j.atmosenv.2025.121533","DOIUrl":"10.1016/j.atmosenv.2025.121533","url":null,"abstract":"<div><div>The interactions between metal ions and humic-like substances (HULIS) in cloud water significantly influence atmospheric metal fate, photochemistry, and cloud processes. Using EEM-PARAFAC, 2D-FTIR-COS, and hetero-2DCOS, under environmentally relevant pH conditions (pH = 6.5), this study systematically investigates complexation mechanisms of six metals (Cu(II), Hg(II), Pb(II), Fe(III), Mn(II), Zn(II)) with HULIS extracted from cloud water. EEM-PARAFAC resolves HULIS into three fluorescent fractions: low-oxygen (C1), high-oxygen (C2), and protein-like (C3). Fe(III) exhibits the strongest binding (logK ≈ 4.89–5.01), preferentially quenching C3, while Pb(II)/Hg(II) interact with C1 and Cu(II) with C2. Mn(II)/Zn(II) enhance fluorescence via alternative mechanisms. 2D-FTIR-COS reveals Fe(III)/Pb(II) target carboxyl/carbonyl groups, Cu(II)/Hg(II) aromatic moieties, and Zn(II) hydroxyl/polysaccharide functionalities. Hetero-2DCOS uncovers sequential structural changes: Fe(III), Cu(II), and Pb(II) induce fluorescence responses before C–H/O–H vibrations, whereas Hg(II) modifies C–H vibrations prior to fluorescence quenching. These findings provide novel molecular insights into metal-HULIS binding dynamics, highlighting HULIS as a critical mediator of metal solubility, transport, and photochemical reactivity in cloud systems, with implications for aerosol properties, climate feedbacks, and pollution mitigation strategies.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"362 ","pages":"Article 121533"},"PeriodicalIF":3.7,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145107041","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":"Will assimilating VIIRS AOD data improve New Delhi's air pollution forecasts as much as assimilating MODIS AOD?","authors":"Rajesh Kumar ,&nbsp;Scott Meech ,&nbsp;Prafull P. Yadav ,&nbsp;William Y.Y. Cheng ,&nbsp;Sachin D. Ghude ,&nbsp;Stefano Alessandrini ,&nbsp;Rajmal Jat ,&nbsp;Gaurav Govardhan","doi":"10.1016/j.atmosenv.2025.121526","DOIUrl":"10.1016/j.atmosenv.2025.121526","url":null,"abstract":"<div><div>This study examines whether fine particulate matter (PM_2.5) forecasts in New Delhi will continue to benefit from assimilation of Visible Infrared Imaging Radiometer Suite (VIIRS) aerosol optical depth (AOD) retrievals in the same way as has been seen from assimilation of Moderate Resolution Imaging Spectroradiometer (MODIS) AOD assimilation. Three experiments were conducted with and without constraining aerosols initialization through assimilation of MODIS and VIIRS AOD retrievals in Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). Satellite AOD assimilation significantly improves the agreement between modeled and Aerosol Robotic Network (AERONET) AOD at Kanpur with most of the changes in PM_2.5 vertical distribution limited to altitudes below 5 km. Consequently, the assimilation of either MODIS or VIIRS AOD retrievals also reduces the mean bias in 72 h PM_2.5 forecasts by 70–86 % and root mean squared error by 20–31 % with improvements of ∼200 μg/m³ during an acute air pollution episode in November 2017. However, the improvements due to VIIRS assimilation are slightly lower (0.5–3 %) than those due to MODIS assimilation. We conclude that VIIRS AOD can effectively replace MODIS in the operational air quality forecasting system after MODIS's end of life and can continue to support air quality management efforts in New Delhi.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121526"},"PeriodicalIF":3.7,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004214","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":"6PPD quinone formation from 6PPD via a radical process and its competing reactions","authors":"Eunji Chae,&nbsp;Sung-Seen Choi","doi":"10.1016/j.atmosenv.2025.121527","DOIUrl":"10.1016/j.atmosenv.2025.121527","url":null,"abstract":"<div><div><em>N</em>-(1,3-Dimethylbutyl)-<em>N′</em>-phenyl-<em>p-phenylenediamine</em> (<em>6PPD</em>) is an essential additive in tire rubber compounds to enhance their lifespan. <em>6PPD quinone (6PPD-Q</em>), a known toxic chemical, is formed through the oxidation of 6PPD. The formation of <em>6PPD-Q is expected to proceed via radical process, as the oxidation reaction necessarily involves an oxygen atom. However,</em> due to the challenges in detecting radical species<em>, many studies have inferred</em> the formation of <em>6PPD-Q based on the neural oxidation products. In this study, the 6PPD oxidation products including radical intermediates</em> were analyzed using direct atmospheric pressure chemical ionization-mass spectrometry (APCI-MS). The formation of <em>6PPD-Q was elucidated by detecting its radical intermediates. The first ketone group in 6PPD-Q is formed through the rearrangement of (6PPD + O − H)</em>^<em>•</em> <em>radical precursor. The second one is generated by the loss of a hydrogen atom from (6PPD + 2O − H)</em>^<em>•</em> <em>radical precursor. The abundance of 6PPD-Q was significantly lower than those of other competing oxidation products. The primary competing reactions include</em> the rearrangements of the two radical precursors into alternative species <em>and the dissociations of 6PPD and oxidation products into</em> nitrobenzene, formylaniline, 4-hydroxydiphenylamine, and 4-nitrodiphenylamine. The favorability of <em>6PPD-Q</em> formation <em>and its competing reactions was explained in terms of thermodynamics.</em></div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121527"},"PeriodicalIF":3.7,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004215","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":"NPF-induced CCN enhancement over an urban location in Eastern Himalayan Foothills: A campaign-based study","authors":"Barlin Das ,&nbsp;Binita Pathak ,&nbsp;Uday Bhattacharjee ,&nbsp;Partha Jyoti Sahu ,&nbsp;Arundhati Kundu ,&nbsp;Arup Borgohain ,&nbsp;Mukunda M. Gogoi ,&nbsp;Shyam S. Kundu ,&nbsp;Kalyan Bhuyan ,&nbsp;Pradip K. Bhuyan","doi":"10.1016/j.atmosenv.2025.121524","DOIUrl":"10.1016/j.atmosenv.2025.121524","url":null,"abstract":"<div><div>The New Particle Formation (NPF) mechanism plays a significant role in regulating the cloud condensation nuclei (CCN). Here, we present results from a campaign mode study during 3 January - 4 February 2023 obtained from simultaneous measurements of particle number concentration within a size range 10–300 nm (N_10-300) using the scanning mobility particle sizer (SMPS) and CCN concentrations (N_CCN) using a CCN Counter (CCNc) over an urban location, Dibrugarh, in the Eastern Himalayan Foothills. The mean diurnal variation of N_CCN at supersaturations (SS) 0.2 %–1.0 % exhibits similar variation to the total number concentration of aerosols (N_10-300) measured by the SMPS. Both exhibit higher concentrations during nighttime and lower during daytime, primarily influenced by atmospheric boundary layer (ABL) dynamics. We have identified four NPF events during the study period. The new particle burst appeared below 25 nm, while the growth process sustained for 12 to 17 h at the growth rate from 4.5 to 7.2 nm h⁻¹. The growth process begins with coagulation, followed by condensation, which becomes the dominant mechanism in the formation of CCN. Further, the enhancement factor of CCN due to NPF (E_N_CCN) was estimated to examine the aerosol-CCN interaction. E_N_CCN was found to vary between 2 and 8 for the four NPF events at the SS range 0.2–1 %, which are comparable to those over many urban places across the globe.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"362 ","pages":"Article 121524"},"PeriodicalIF":3.7,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145155845","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":"Ammonia emissions from an avian-rich island in the Great Barrier Reef: Environmental drivers and observational insights","authors":"Lili Wu ,&nbsp;Eva Johanna Horchler ,&nbsp;Zoran Ristovski ,&nbsp;Junwen Liu ,&nbsp;Fei Yu ,&nbsp;Shijie Han ,&nbsp;Wenhui Zhao ,&nbsp;Lara Richards ,&nbsp;Daniel Harrison ,&nbsp;Junyu Zheng ,&nbsp;Branka Miljevic","doi":"10.1016/j.atmosenv.2025.121525","DOIUrl":"10.1016/j.atmosenv.2025.121525","url":null,"abstract":"<div><div>Ammonia, a key alkaline gas in the atmosphere, plays a significant role in new particle formation and cloud condensation nuclei activity, particularly in marine environments. On islands rich in avian fauna, ammonia emissions often exceed those in urban areas and are influenced by environmental factors such as temperature and precipitation. This study investigated the NH₃ emissions on Heron Island in the Great Barrier Reef using three different methods, namely offline active sampling, offline passive sampling, and online nitrate chemical ionization mass spectrometry (NO₃-CIMS). The average NH₃ mixing ratio of active sampling, passive sampling, and NO₃-CIMS during the sampling period was 29 ± 23 ppb, 29 ± 22 ppb, and 39 ± 19 ppb. Results from the three methods revealed consistent NH₃ mixing ratio trends. Changes in NH₃ mixing ratio were highly correlated with precipitation events. During precipitation periods, the NH₃ mixing ratio increased significantly within 30 min to a few hours after the rain started. Laboratory bird guano experiments further proved that NH₃ emissions are more influenced by precipitation than temperature. Besides, the δ¹⁵N-NH₃ values (−19.5 ‰ to −11.7 ‰) measured by passive samplers negatively correlated with NH₃ levels, confirming seabird guano as the primary NH₃ source. These findings highlighted the dynamic behavior of NH₃ emissions and their sensitivity to environmental factors, shedding light on the potential importance of the Great Barrier Reef ecosystem for atmospheric processes relevant to aerosol formation.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121525"},"PeriodicalIF":3.7,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004216","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":"Study of the chemical kinetic mechanism and aldehyde emissions in methanol/diesel dual-fuel combustion","authors":"Guangyuan Bao ,&nbsp;Chao He ,&nbsp;Wei Zhang ,&nbsp;Jiaqiang Li","doi":"10.1016/j.atmosenv.2025.121528","DOIUrl":"10.1016/j.atmosenv.2025.121528","url":null,"abstract":"<div><div>To investigate the combustion characteristics of diesel/methanol in the engine cylinder, this study developed a chemical kinetics model for the diesel/methanol (DM) dual-fuel mechanism, comprising 288 reactions and 101 species. The simplified DM mechanism was optimized by adjusting the rate parameters of key reactions, combined with a sensitivity evaluation system for ignition delay time (IDT) and laminar flame speed (LFS). The model's predictions for IDT, LFS, and the concentrations of key species were verified experimentally using a zero-dimensional model. The effects of methanol substitution rate, and altitude on the formation of aldehyde pollutants were systematically analyzed. The results show that the DM mechanism can accurately predict the IDT, LFS, and the formation of key species for a single fuel within the temperature range of 318 K–2000 K, equivalence ratio range of 0.5–2.0, and pressure range of 0.1 MPa–2 MPa. Compared with existing mechanisms, the DM mechanism significantly improves prediction accuracy for these parameters, with R² values greater than 0.96 and RMSE values below 0.05, demonstrating higher accuracy and consistency. Furthermore, increasing the methanol substitution rate significantly reduces CH₂O emissions, while altitude lead to a marked increase in CH₂O and CH₃CHO emissions. Therefore, the proposed DM mechanism shows strong applicability and generalization capability in combustion characteristic prediction and pollutant emission control.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"362 ","pages":"Article 121528"},"PeriodicalIF":3.7,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145009883","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 spatial diversity of secondary organic carbon aerosols at the city level: insights from explainable machine learning","authors":"Xiaojian Xu ,&nbsp;Cheng Wu ,&nbsp;Chenglei Pei ,&nbsp;Mei Li ,&nbsp;Chunlei Cheng ,&nbsp;Menghua Lu ,&nbsp;Zhijiong Huang ,&nbsp;Baoling Liang ,&nbsp;Xinkun Fang ,&nbsp;Mengxi Ye ,&nbsp;Dui Wu","doi":"10.1016/j.atmosenv.2025.121522","DOIUrl":"10.1016/j.atmosenv.2025.121522","url":null,"abstract":"<div><div>Secondary organic carbon (SOC) is a ubiquitous component of atmospheric fine particles but its spatial diversity at the city level has rarely been characterized. This study is the first of its kind that examine the spatial diversity of SOC at the city level, utilizing hourly carbon analyzer data of 2022 from four representative observation sites in the megacity of Guangzhou, China (GYQ, DXC, NSPZ and CHLK) encompassing urban, suburban, and rural areas. The minimum R-squared (MRS) method was adopted for SOC estimation. This study pioneers the use of explainable machine learning for SOC reconstruction with the CatBoost algorithm and Shapley Additive Explanations (SHAP) to quantify the contribution of input factors. The 12 input factors were grouped into four categories: photochemical reactions, aqueous-phase reactions, primary emissions, and meteorological conditions. Photochemical reactions dominate variations in SOC concentrations at urban and suburban sites. The annual average contribution of photochemical reactions gradually decreases from urban (∼50%) to rural sites (∼30%). The aqueous phase and meteorological conditions both contribute ∼20% of SOC variations. Primary emissions contribution to SOC variations is less than 10% for suburban and urban sites but the contribution increased to 33% for the rural site. Further analysis suggests that the high contribution of primary emissions at the rural site reflects the influence of aged urban plumes. SOC at the suburban site is heavily influenced by shipping emissions due to its coastal location. SOC at the two urban sites exhibits different dependence on Non-methane hydrocarbon (NMHC) and O₃ levels, which is related to the uneven influence of transported SOC at the two urban sites. SOC from local, regional, and background contributions was quantified at the urban site DXC using multiple-site observations. It was found that approximately 50% of the SOC originated from outside Guangzhou city. This indicates that future efforts to control SOC may require a shift from relying solely on local mitigation measures to a more comprehensive approach that considers the spatial diversity of SOC for effective air quality management.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121522"},"PeriodicalIF":3.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003607","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":"Corrigendum to “Exploring fine-aerosol episodes in urban Seoul during the cold season of the 2021 SIJAQ campaign: Measurement evidences of heterogeneous reactions on black carbon particles” [Atmospheric Environ. 342 (2025) 1-12 120926]","authors":"Saehee Lim ,&nbsp;Min-Suk Bae ,&nbsp;Jihi Jang ,&nbsp;Anubhav Kumar Dwivedi ,&nbsp;Junsu Gil ,&nbsp;Joo ae Kim ,&nbsp;Meehye Lee ,&nbsp;Sea-Ho Oh ,&nbsp;Sun-A Shin ,&nbsp;Lim-Seok Chang","doi":"10.1016/j.atmosenv.2025.121521","DOIUrl":"10.1016/j.atmosenv.2025.121521","url":null,"abstract":"","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121521"},"PeriodicalIF":3.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145044633","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":"Spatial distribution, potential sources, and dry deposition fluxes of per- and polyfluoroalkyl substances (PFAS) in atmospheric particles (PM2.5) in the offshore eastern China sea (OECS)","authors":"Hao Sun ,&nbsp;Shuai Sun ,&nbsp;Xuan Jia ,&nbsp;Yadi Lou ,&nbsp;Xing Liu ,&nbsp;Zilan Wu ,&nbsp;Yitao Pan ,&nbsp;Zhongsheng Lin ,&nbsp;Ziwei Yao ,&nbsp;Jianmin Chen","doi":"10.1016/j.atmosenv.2025.121523","DOIUrl":"10.1016/j.atmosenv.2025.121523","url":null,"abstract":"<div><div>A total of 26 alternative and per- and polyfluoroalkyl substances (PFAS) were investigated in atmospheric particles collected above the offshore Eastern China Sea (OECS) during a research cruise from April 20 to May 18, 2018. The total concentrations of these 26 PFAS ranged from 35.59 to 1646.53 pg/m³, with an average of 316.79 pg/m³. The concentrations of short-chain perfluorocarboxylic acids (PFCAs) were significantly higher than those of long-chain PFCAs, with perfluorobutanoic acid (PFBA) being the dominant PFCA congener. PFBA was detected in all particle samples, accounting for 77.9 % of the total PFCAs, with an average concentration of 222.05 pg/m³. Moreover, perfluorosulfonic acid (PFSA) analogues showed lower concentrations and detection frequencies than PFCAs, possibly due to the ban on PFOS-related substances. Other PFAS congeners, such as fluorotelomer sulfonic acids (FTSAs) and perfluorooctane sulfonamide (FOSA), were detected at lower concentrations, possibly because they predominately exist in the gaseous phase. The levels of PFAS in atmospheric particles over the OECS were comparable or higher than those in other areas of China and abroad. The coast of Fujian Province and the Yangtze River estuary were two hot-spots for PFAS, mainly influenced by emission sources (various industrial and port transportation activities). In contrast, regions with low PFAS concentrations likely benefited from their geographical locations and meteorological factors, as inferred from backward trajectory analysis. Positive matrix factorization (PMF) modeling identified four primary sources of PFAS; electronic product manufacturing, PFOS-based products, aqueous film-forming foam extinguishing (AFFF) agent usage, and paper packing production. Among these, electronic product manufacturing and PFOS-based products contributed more of the PFAS in the PM_2.5 particle samples. The estimated dry deposition of ΣPFAS ranged from 0.77 to 35.56 ng/m²/d, with an average value of 6.55 ng/m²/d. PFBA, perfluorooctanoic acid (PFOA), and perfluoropentanoic acid (PFPeA) were the dominant contributors. The total PFAS input into the East China Sea and the Yellow Sea via dry deposition in Spring was estimated to be about 518 kg and 328 kg, several times lower than the riverine input reported in previous studies. These findings clearly demonstrate that dry deposition is a significant pathway by which PFAS enter seawater and needs more attention.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"361 ","pages":"Article 121523"},"PeriodicalIF":3.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145007495","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":"Aircraft observations of natural and anthropogenic substances during the Asian outflow over the East China Sea in the winter of 2000","authors":"Mandira Pradhananga Adhikari ,&nbsp;Ippei Nagao ,&nbsp;Nagayoshi Katsuta ,&nbsp;Masako Kagawa ,&nbsp;Yutaka Ishizaka","doi":"10.1016/j.atmosenv.2025.121517","DOIUrl":"10.1016/j.atmosenv.2025.121517","url":null,"abstract":"<div><div>To investigate the impacts of anthropogenic and natural substances transported from the Asian continent in winter on the abundance of atmospheric aerosols and cloud condensation nuclei (CCN), in the planetary boundary layer (PBL) and free troposphere (FT) over the receptor region, aircraft observations of number concentrations of aerosol and CCN as well as sulfur dioxide (SO₂) were carried out over the East China Sea (ECS) during the Asian Atmospheric Particulate Environmental Change Experiment 1 (APEX-E1) in December 2000. Reanalysis data of meteorology (ERA5) and aerosols (MERRA-2) were used to interpret the observation results. The results on December 23 were characterized by the highest concentrations of all parameters including CCN more than 400 cm⁻³ at supersaturation (SS) of 0.40 % and SO₂ (&gt;4 ppbv) in the PBL under relatively fresh polluted air, due to rapid transport of anthropogenic and natural substances through the PBL by subsidence of air and strong winds behind cold front. On December 24, anthropogenic pollutants and dust particles were transported into the FT by ascent of air associated with a low-pressure system over the Asian continent. SO₂ and coarse mode aerosols were higher than those in the PBL and CCN concentration was more than 100 cm⁻³ (SS = 0.40 %). In addition, this kind of ascent of air to the lower FT occurs several times on average in December. Our results suggest that in addition to traditional trajectory analysis, it is necessary to incorporate the history analysis of vertical transport and wind-induced aerosol emissions along the transport pathway.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"362 ","pages":"Article 121517"},"PeriodicalIF":3.7,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119179","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}