Atmospheric Environment最新文献

{"title":"Very volatile and volatile organic compounds (VVOCs/VOCs) and endotoxins in the indoor air of German schools and apartments (LUPE10)","authors":"Hermann Fromme ,&nbsp;Marina Sysoltseva ,&nbsp;Alexandra Schieweck ,&nbsp;Claudia Röhl ,&nbsp;Felicia Gerull ,&nbsp;Rafael Burghardt ,&nbsp;Andreas Gessner ,&nbsp;Heike Papavlassopoulos ,&nbsp;Wolfgang Völkel ,&nbsp;Wolfgang Schober","doi":"10.1016/j.atmosenv.2025.121178","DOIUrl":"10.1016/j.atmosenv.2025.121178","url":null,"abstract":"<div><div>People, including sensitive population groups such as children, spend over 90 % of their time indoors and are exposed to volatile and very volatile organic compounds (VOCs/VVOCs) and endotoxins. We measured 34 VVOCs, 69 VOCs, two organic acids, and endotoxins in the indoor air of 34 apartments and 27 classrooms using four different sampling techniques and analytical methods. Our study aimed to provide a comprehensive overview of a broad spectrum of substances rarely measured in indoor air. The following substance classes showed the highest sum medians in classrooms and apartments: alcohols 249 μg/m³ and 518 μg/m³, aldehydes/acetone 81.6 μg/m³ and 121 μg/m³ and organic acids 61 μg/m³ and 82 μg/m³. The individual substances with the highest medians were ethanol &gt; acetic acid &gt; acetone &gt; decamethylcyclopentasiloxane &gt; formaldehyde &gt; acetaldehyde. The median of the total volatile organic compounds as the sum of the VOCs of C₆-C₁₆ was 253 μg/m³ (range: 638–3369 μg/m³) in the apartments and 277 μg/m³ (61–900 μg/m³) in the classrooms. The median (95th percentile) levels of endotoxins in the classrooms and apartments were 5.8 EU/m³ (15.3 EU/m³) and 0.26 EU/m³ (0.91 EU/m³), respectively. Concentrations in apartments are significantly lower than in schools. According to current knowledge, levels pose no health risk.</div><div>In addition to the classic VOCs, VVOCs should also be measured to a greater extent, as considerable exposure to substances from this group is expected indoors. These results underline the urgent need for further research to improve indoor air quality and protect public health.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"351 ","pages":"Article 121178"},"PeriodicalIF":4.2,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143682425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal variations in whole–ecosystem BVOC emissions and ozone fluxes from a tropical rubber tree plantation in China","authors":"Jianhui Bai ,&nbsp;Zhixiang Wu ,&nbsp;Chuan Yang ,&nbsp;Alex Guenther","doi":"10.1016/j.atmosenv.2025.121182","DOIUrl":"10.1016/j.atmosenv.2025.121182","url":null,"abstract":"<div><div>Biogenic volatile organic compound (BVOC) and O₃ fluxes and concentrations, along with environmental variables such as solar radiation and air temperature, were measured in a tropical rubber tree plantation in China from August 2018 to June 2019. The detected BVOC fluxes included five terpenoid compounds, isoprene and four monoterpenes, measured using a gradient (GRA) sampling system deployed on an above canopy flux tower. Isoprene accounted for only 13 % of total terpenoid emissions at this site. The remaining 87 % of total terpenoid emissions were dominated by α-pinene (16 %), camphene (20 %), β-pinene (19 %), and limonene (32 %). Isoprene and monoterpene emission fluxes showed clear diurnal variations, with higher emissions around noon and lower emissions in the morning and late evening. The emission peaks typically occurred several hours after the peak in photosynthetically active radiation (PAR) around noon. Isoprene and monoterpene emissions also varied seasonally. O₃ fluxes were negative (downward) and peaked around noon, with the highest fluxes observed in the dry season. BVOC concentrations at the bottom and top levels were higher around noon, and concentrations were higher at the bottom level than at the top level, indicating upward fluxes. O₃ concentrations at the bottom and top levels showed clear diurnal variations, with higher values around noon. O₃ concentrations at the top level were higher than those at the bottom level. BVOC emissions and ozone flux, along with their concentrations, are correlated with atmospheric conditions including PAR, air temperature (T), and water vapor and appear to be influenced by smoke plumes. The relationships between BVOC emission, ozone flux, atmospheric conditions (represented by S/Q, the ratio of solar scattered radiation to global radiation), and their concentrations and S/Q were investigated. These relationships can be used to better understand and inform strategies for controlling ozone pollution in China and other locations.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"351 ","pages":"Article 121182"},"PeriodicalIF":4.2,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143716002","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":"Spectral characteristics of water-soluble Brown carbon and it's radiative impacts on the atmosphere of Dhaka, Bangladesh","authors":"Md Al-amin Hossen ,&nbsp;Shatabdi Roy ,&nbsp;Samiha Nahian ,&nbsp;Shahid Uz Zaman ,&nbsp;Abu Selim ,&nbsp;Abdus Salam","doi":"10.1016/j.atmosenv.2025.121185","DOIUrl":"10.1016/j.atmosenv.2025.121185","url":null,"abstract":"<div><div>Brown carbon (BrC) is the ubiquitous part of the atmospheric organic carbon. It absorbs solar lights and greatly impacts the Earth's radiative balance. This study examines the spectral characteristics of BrC and its radiative effect in the Dhaka South (DS) site and Dhaka North (DN) site from July 2023 to January 2024 with a high-volume particulate matter sampler on quartz filters. Spectral characteristics such as absorption coefficient (b_abs-λ), mass absorption efficiency (MAE), absorption angstrom exponent (AAE), and refractive index (Κ_abs-λ) were determined by using a UV–visible spectrophotometer, and fluorescence emission spectra were analyzed in different pH by the fluorescent spectrophotometer. The concentrations of BrC and black carbon (BC) were determined by an aethalometer. The mean concentrations of BrC and BC in Dhaka city were 18.63 ± 3.84 μg m⁻³ and 17.93 ± 3.82 μg m⁻³, respectively. The AAE values lie in the range of 3.20–4.01 (DN) and 3.27–4.53 (DS), and the radiative forcing efficiency of BrC was obtained at 4.43 ± 1.02 W g⁻¹ in DN and 3.93 ± 0.74 W g⁻¹ in DS, indicating the presence of highly light-absorbing BrC in these locations. Average MAE and Κ_abs-λ values were 1.55 ± 0.45 m²g^-1 and 0.044 ± 0.013, respectively, in DS, alternatively 1.84 ± 0.59 m²g^-1 and 0.052 ± 0.016 in DN. The fluorescence excitation-emission spectra confirmed the presence of a polyconjugate cyclic ring with multifunctional groups in the structure of BrC. Light absorption properties and fluorescence emission spectra were varied with the change of pH. As the pH increased (2–8), the AAE value decreased and MAE_BrC-365 increased due to protonation or deprotonation. This study highlights that the BrC has a significant impact on the air quality as well as the Earth's radiative balance, emphasizing its strong light-absorbing properties and variability with environmental factors.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"351 ","pages":"Article 121185"},"PeriodicalIF":4.2,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726177","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":"Distribution characteristics and air-quality effect of intercontinental transport dust: An unexpected dust storm case study in China","authors":"Hongzi Pan ,&nbsp;Zhiyuan Hu ,&nbsp;Taichen Feng ,&nbsp;Zhongwei Huang ,&nbsp;Qiantao Liu ,&nbsp;Guolin Feng","doi":"10.1016/j.atmosenv.2025.121177","DOIUrl":"10.1016/j.atmosenv.2025.121177","url":null,"abstract":"<div><div>An unexpected dust storm swept throughout China from April 9 to 16, 2023. Many studies have explored the characteristics of the weather system process during this case. However, the distribution characteristics and air-quality effect of this dust storm have been less discussed, especially for the sources of dust. Here, the Weather Research and Forecasting model coupled with chemistry (WRF-Chem) model along with MODIS satellite observations, ERA5 reanalysis data and the HYSPLIT backward trajectory model was used to analyze the transport characteristics and the contributions of dust from different sources during the period of this dust storm. The results showed that dust emissions from North Africa (NA) and the Middle East (ME), aided by atmospheric circulation patterns that facilitate long-range dust transport, collectively led to an increase in dust influx into East Asia (EA). A low-pressure system's eastward journey, starting from NA, passing through ME, and eventually reaching EA, along with the prevailing westerly winds, played a crucial role in this process.</div><div>During long-range transport, dust originating from NA and ME was typically split into northern and southern branches by the Tibetan Plateau (TP), with the northern branch being predominant. The dust primarily entered EA through the upper troposphere, where the contribution of local dust from EA tended to diminish. Evenly, ME dust was increasingly becoming the dominant source in South China. Despite this, the air quality below 500 hPa in North and 700 hPa in South China was primarily influenced by EA dust. In contrast, dust transported over long distances from ME and NA tended to rise to higher altitudes, thereby impacting PM₁₀ concentrations and air quality in upper layers. This research offered novel insights into the significant role of long-range transported dust during a single dust event in EA.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"350 ","pages":"Article 121177"},"PeriodicalIF":4.2,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679412","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 regional and local sources of particle lung deposited surface area (LDSAal) and aerosol physical and chemical characteristics in a major Central European city","authors":"Teemu Lepistö ,&nbsp;Minna Aurela ,&nbsp;Henna Lintusaari ,&nbsp;Ville Silvonen ,&nbsp;Lassi Markkula ,&nbsp;Jussi Hoivala ,&nbsp;Roel P.F. Schins ,&nbsp;Hilkka Timonen ,&nbsp;Pasi Jalava ,&nbsp;Sanna Saarikoski ,&nbsp;Topi Rönkkö","doi":"10.1016/j.atmosenv.2025.121181","DOIUrl":"10.1016/j.atmosenv.2025.121181","url":null,"abstract":"<div><div>The physical and chemical composition of ambient fine particles is crucial to understand when assessing the adverse health effects of air pollution. Currently, particle health effect estimations as well as air quality monitoring are mainly based on the particle mass (like PM_2.5). However, PM_2.5 cannot be used to assess the effects of ultrafine particles, nor it cannot explain why in some regions PM mass seems to be relatively more harmful. In this study, the detailed physical and chemical characteristics of urban aerosol, together with particle lung deposited surface area (LDSA^al) measurement, were analysed in Düsseldorf, Germany, to understand the aerosol that people are exposed to in a typical large Central European city. Overall, LDSA^al, PM_2.5 and chemical composition were mainly dependent on the regional aerosol, which was linked to aged aerosol as well as traffic and biomass burning within the city. Near pollution hotspots (airport, river, city centre), LDSA^al increased by 14–19 %, whereas PM_2.5 increased by 4–13 %. However, a major fraction of particles were smaller than 10 nm, suggesting potential health effects (like brain effects) without clear contribution to LDSA^al. Particle number concentrations were clearly elevated near the pollution hotspots, especially the airport, showing the importance of non-road-traffic local pollution sources in urban environments. The study highlights the need to control pollution sources both outside and within cities in Central European cities. Also, the need to understand the health-damaging potential of ultrafine particles, including the semi-volatile, non-volatile and sub-10 nm fractions, is emphasised.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"350 ","pages":"Article 121181"},"PeriodicalIF":4.2,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wind tunnel model of the Jack Rabbit II field experiments in the mock urban array: Part 2. approach wind conditions and particle image velocimetry measurements of simulated chlorine releases","authors":"Paulo V.d.F. Lopes,&nbsp;Thomas O. Spicer,&nbsp;Chad T. Smith","doi":"10.1016/j.atmosenv.2025.121179","DOIUrl":"10.1016/j.atmosenv.2025.121179","url":null,"abstract":"<div><div>The Jack Rabbit II (JR-II) Mock Urban Environment field test was reproduced in a 1:50 scale physical model in the wind tunnel at the Chemical Hazards Research Center of the University of Arkansas. The agreement of the approaching wind characteristics between field test and model was verified using 3D Laser Doppler Velocimetry (LDV). 2D Particle Image Velocimetry (PIV) tests were conducted in the model to obtain velocity measurements in the MUE. Velocity measurements taken before and during a simulated chlorine release were compared. PIV results show the general flow complexity in the last rows of the MUE and the impact of the release in two different wind conditions from JR-II. Simulations of neutrally buoyant releases conducted in one set of wind conditions showed that the impact on the release was mostly a result of the added density of the chlorine simulant and not from the added velocity of the gas release. Changes in the dividing streamline at CONEX 11.4 and in the vorticity around the model building were also observed, especially for lower atmospheric wind speed (momentum). PIV results show the impact of the release in two different perspectives, from the side and from above the MUE. Physical (wind tunnel) modeling can supplement the information available from field tests to provide validation data sets for computational models, and such exercises can even be more valuable for computational model validation because the initial conditions in wind tunnel tests are generally better understood than in field tests.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"353 ","pages":"Article 121179"},"PeriodicalIF":4.2,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838075","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":"Tracking NO2 and CO pollution hotspots at provincial scale in China with TROPOMI observations and image segmentation method","authors":"Mingyu Zeng ,&nbsp;Minghui Tao ,&nbsp;Rong Li ,&nbsp;Pengfei Ma ,&nbsp;Lijuan Zhang ,&nbsp;Jun Wang ,&nbsp;Lunche Wang ,&nbsp;Yi Wang ,&nbsp;Haijun Huang ,&nbsp;Liangfu Chen","doi":"10.1016/j.atmosenv.2025.121176","DOIUrl":"10.1016/j.atmosenv.2025.121176","url":null,"abstract":"<div><div>Satellite measurements of short-lived gaseous pollutants such as nitrogen dioxide (NO₂) and carbon monoxide (CO) provide an unprecedented opportunity to infer global distribution of their emission sources. However, the great differences in the magnitude of anthropogenic emissions have hampered the identification of pollution sources with satellite observations. In this study, we identified NO₂ and CO pollution hotspots in China with oversampled TROPOspheric Monitoring Instrument (TROPOMI) concentration data by utilizing an image segmentation method at provincial scale. We also determined the major emitting sectors associated with the pollution hotspots in each province. Based on NO₂ pollution hotspots, we can find major emission sources, such as ports, airports, industrial and urban areas. In the hotspots of most provinces, Steel plant, Coke plant, and Power plant were identified as the main NO_x emission sources. CO pollution hotspots were closely linked to Steel plant, with additional contributions from Coke plant, Chemical industry, and Non-ferrous metal smelting in certain provinces. The pollution hotspots and their corresponding concentrations yielded a relatively strong correlation with Multi-resolution Emission Inventory for China (MEIC) (For NO₂, the R² was 0.937 in provinces with small land area and 0.654 in others, while for CO, the R² was 0.849 and 0.659, respectively). Our results can provide an observational constraint on the spatial locations of NO_x and CO emission sources for emission inventories.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"351 ","pages":"Article 121176"},"PeriodicalIF":4.2,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143716005","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":"Molecular level characteristics and sources of rainwater water-soluble organic matter in different regions of China by FT-ICR MS","authors":"Cuiping Ning ,&nbsp;Yutong Tang ,&nbsp;Shuai Sun ,&nbsp;Dan Wang ,&nbsp;Yuan Gao","doi":"10.1016/j.atmosenv.2025.121175","DOIUrl":"10.1016/j.atmosenv.2025.121175","url":null,"abstract":"<div><div>Rainwater water-soluble organic matter (WSOM) constitutes a complex mixture that holds a pivotal role in biogeochemical cycles and climate change. Understanding its chemical composition helps better to reveal its atmospheric behavior. In this study, rainwater samples were collected from three Chinese cities to explore their WSOM molecular composition and sources. These rainwater samples contained significant amounts of both natural and anthropogenic WSOM owing to diverse environmental settings and extensive human activities. Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was employed to analyze the molecular diversity of rainwater WSOM. A total of 1684, 2024, and 1104 molecular formulas were identified in rainwater WSOM from Anshan, Guangzhou, and Nanjing, China, respectively. The results reveled that sulfur-containing compounds (including CHOS and CHONS) dominated the rainwater WSOM in Anshan (74.9 %), with a notable presence of nitrooxy-organosulfates. In contrast, in Guangzhou, typical biogenic derivatives of CHO compounds contributed more to the rainwater WSOM (50.5 %). In Nanjing, the sulfur-containing compounds and CHO compounds were primarily composed of nitrooxy-organosulfates and saturated fatty acids, respectively, comprising 48.6 % and 43.8 % of the rainwater WSOM. On the whole, rainwater WSOM mainly originated from industrial emissions, secondary generation, biomass burning, and vehicle emissions.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"350 ","pages":"Article 121175"},"PeriodicalIF":4.2,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679409","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":"Direct sun total NO2 column measurements at Thessaloniki, Greece with two DOAS systems and comparisons with S5P/TROPOMI","authors":"Dimitrios Nikolis,&nbsp;Alkiviadis Bais,&nbsp;Dimitris Karagkiozidis,&nbsp;Maria-Elissavet Koukouli,&nbsp;Dimitris Balis","doi":"10.1016/j.atmosenv.2025.121161","DOIUrl":"10.1016/j.atmosenv.2025.121161","url":null,"abstract":"<div><div>Multiple Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) instruments have been operating in the Laboratory of Atmospheric Physics (LAP), Thessaloniki, Greece over a decade to monitor trace gases in the troposphere. In this work, we present methodology, applied for the first time in LAP for retrieving total NO₂ columns in the atmosphere by applying the Direct Sun DOAS technique (DS-DOAS) on solar direct radiance spectra acquired with a research grade MAX-DOAS system, Delta. For the retrieval of total NO₂ two spectral fitting methods were tested using cross sections of NO₂ at two different temperatures for the tropospheric and the stratospheric component. The method that is based on concurrent spectral DOAS fittings with NO₂ cross sections at two temperatures (294 K and 220 K) (2T method) produces results of better quality as compared to the method using NO₂ cross section at one 254.5 K (1T method), with latter underestimating the total NO₂ vertical column density by up to 15%. This was verified by the good agreement (correlation coefficient R = 0.973) against the total NO₂ columns measured by an independently calibrated collocated Pandora system. Finally, the total NO₂ columns derived from the Delta instrument were compared with collocated observations by S5P/TROPOMI, showing an underestimation of the latter by up to 40% for days with high NO₂ concentrations, while the agreement is better under low NO₂ conditions. The overall agreement between the satellite and Delta system observations is characterized by a correlation coefficient of 0.82 and a mean bias of −2.63 ± 2.75 Pmolec/cm².</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"352 ","pages":"Article 121161"},"PeriodicalIF":4.2,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hourly estimation of black carbon in China based on sparse observation data and stacking model","authors":"Weijie Li ,&nbsp;Yaqiang Wang ,&nbsp;Zhaoliang Zeng ,&nbsp;Ziwei Yi ,&nbsp;Huizheng Che ,&nbsp;Xiaoye Zhang","doi":"10.1016/j.atmosenv.2025.121164","DOIUrl":"10.1016/j.atmosenv.2025.121164","url":null,"abstract":"<div><div>Black carbon (BC) is a highly absorbent aerosol that significantly impacts regional air quality, public health, and global climate change. In this study, we develop a machine learning-based stacking model to estimate hourly BC in China, using observational data from 36 BC sites of the China Atmosphere Watch Network (CAWNET) from 2020 to 2023. The stacking model shows strong robustness and high accuracy nationwide, achieving a Pearson correlation coefficient (R) of 0.79 and a root mean square error (RMSE) of 0.60 μg/m³. Compared to Tracking Air Pollution in China (TAP), the stacking model reduces bias by 33.8% in urban areas and 56.9% in rural areas. According to this model, the urban BC concentration is 48.5% higher than that in rural areas across China. North China Plain, Central China, and the Sichuan Basin continue to be the regions with the highest BC concentrations in China, with average concentrations of 1.73 ± 0.66 μg/m³, 1.61 ± 0.55 μg/m³, and 1.71 ± 0.58 μg/m³, respectively, from 2020 to 2023. During the COVID-19, urban areas experienced a consistent decline in BC concentrations from 2020 to 2022, followed by a rebound in 2023 (rural areas rebound in early 2022). Our research highlights that these high-quality hourly estimated BC concentrations can reveal pollution distribution patterns in both urban and rural areas, as well as during specific time periods, thereby providing crucial support for developing more accurate and effective emission reduction strategies, improving air quality, mitigating climate change, and protecting public health.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"350 ","pages":"Article 121164"},"PeriodicalIF":4.2,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143601286","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}