Atmospheric Environment最新文献

{"title":"Seasonal chemical characteristics and formation of potential secondary aerosols of a remote area in South Korea using an oxidation flow reactor","authors":"Seokwon Kang ,&nbsp;Sungchul Hong ,&nbsp;Yongmi Lee ,&nbsp;Gyutae Park ,&nbsp;Taehyun Park ,&nbsp;Jihee Ban ,&nbsp;Kyunghoon Kim ,&nbsp;Yoonseo Kim ,&nbsp;Yujin Choi ,&nbsp;Jinsoo Park ,&nbsp;Joon-Young Ahn ,&nbsp;Jungmin Park ,&nbsp;Myungsoo Yoo ,&nbsp;Chan-Soo Jeon ,&nbsp;Jinsoo Choi ,&nbsp;Taehyoung Lee","doi":"10.1016/j.atmosenv.2025.121216","DOIUrl":"10.1016/j.atmosenv.2025.121216","url":null,"abstract":"<div><div>Due to the complicated characteristics of secondary aerosols (SAs), their study requires research into their formation and oxidation processes under diverse atmospheric conditions and reactions. Moreover, the increasing atmospheric pollution in Korea has been attributed to factors such as long-range transport of pollutants from China and emissions from domestic sources like cities, power plants, and industrial complexes. In this study, an oxidation flow reactor (OFR) was utilized to assess the chemical characteristics of potential SAs in Korea's background atmosphere. Sampling was conducted from 2019 to 2021 on Baengnyeong Island (37.967° N, 124.630° E), located west of the Korean Peninsula and approximately 180 km from China's Shandong Peninsula. The OFR, coupled with a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and various gas monitors (SO₂, NO, NO₂, NO_X, CO, NH₃, and O₃), facilitated the analysis of the chemical composition of potential SAs. Additionally, to analyze long-range transport from Baengnyeong Island to Seoul, data on SAs and gaseous pollutants from the island were compared with those from Seoul. Results indicate that the potential SAs generated by the OFR were influenced by ozone (O₃) and relative humidity (RH) levels. The concentration of these potential SAs increased with aging time and varied depending on O₃ and RH levels. During spring, elevated PM₁ concentrations in Seoul were noted, driven by additional SAs from photochemical reactions in inland regions. In contrast, during winter, the formation of certain SAs was predominantly due to long-range transport or the accumulation of domestic pollutants in the atmosphere.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"355 ","pages":"Article 121216"},"PeriodicalIF":4.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144068891","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":"Extreme surface ozone episodes over the Arabian Gulf and their relationship with meteorological conditions","authors":"Abdulilah Khalid Alduwais ,&nbsp;Hari Prasad Dasari ,&nbsp;Harikishan Gandham ,&nbsp;Rama Krishna Karumuri ,&nbsp;Badr H. Alharbi ,&nbsp;Karumuri Ashok ,&nbsp;Ibrahim Hoteit","doi":"10.1016/j.atmosenv.2025.121213","DOIUrl":"10.1016/j.atmosenv.2025.121213","url":null,"abstract":"<div><div>In this study, we investigated the seasonal distribution of extreme surface ozone (O₃) episodes in association with meteorological conditions over the Arabian Gulf (AG) between 2016 and 2019. We used hourly surface O₃ measurements from the United States Embassy in Manama and air temperature observations from the Iowa Environmental Mesonet. We computed the maximum daily 8-h average of O₃ using the Air Quality Index methodology. The results showed that the air quality in Manama can be categorized as “good,” “moderate,” “unhealthy for sensitive groups,” “unhealthy,” and “very unhealthy” for 45.31 %, 20.61 %, 19.08 %, 11.63 %, and 3.37 % of the time, respectively. The extreme days, defined as days with MDA8-O₃ ≥ 86 ppb, occurred 72.11 % in summer, 15.65 % in fall, 12.24 % in spring. No extremes were recorded in winter. Our analysis of surface O₃ values obtained from the Copernicus Atmosphere Monitoring Service showed that the O₃ levels during summer extremes were higher by 10 ppb than their climatological mean. We then categorized the O₃ summer extremes into single-day episodes (SDEs) and multi-day episodes (MDEs), revealing that most of the extremes (73.58 %) were MDEs. An analysis of meteorological conditions using the fifth-generation atmospheric reanalysis from the European Centre for Medium-Range Weather Forecasts, MODIS-Terra, and the Clouds and the Earth's Radiant Energy System database revealed that the MDEs exhibit increased temperatures, temperature subsidence form the mid-troposphere, weakened wind speeds, low aerosol optical depth, and increased insolation. These conditions are less pronounced during SDEs. Moreover, 5.67 % of the summer extremes were associated with stratospheric intrusions.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"352 ","pages":"Article 121213"},"PeriodicalIF":4.2,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785458","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":"Substantial impacts of absorbing aerosols on PBL evolution in EDMF-AERO modeling framework","authors":"G.M. Florczyk ,&nbsp;K.M. Markowicz ,&nbsp;M.L. Witek","doi":"10.1016/j.atmosenv.2025.121192","DOIUrl":"10.1016/j.atmosenv.2025.121192","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Understanding the interactions between atmospheric aerosols and the evolution of the planetary boundary layer (PBL) is important for human health, climate, and weather forecasting models. In this study, an eddy-diffusivity mass-flux (EDMF) model is coupled with a radiative transfer model (RTM) to investigate the effects of aerosol optical depth &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;τ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;λ&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and single scattering albedo &lt;span&gt;&lt;math&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt; on the growth and thermodynamics of the PBL, or the so-called aerosol-PBL interactions (API). The developed model, called EDMF-AERO, was first extensively validated against in-situ radiosonde and microwave radiometer (MWR) observations in the summer, showing very good performance and enabling us to study the API effects proposed in the literature called stove and dome. Having established the model’s satisfactory accuracy we performed a sensitivity study, isolated API effects study, and estimated which compound effect of API influences PBL development more. For the stove case for &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;τ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;500&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;9&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, the PBL growth speeds up &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;∼&lt;/mo&gt;&lt;mn&gt;8&lt;/mn&gt;&lt;mtext&gt;%&lt;/mtext&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and warms up &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;∼&lt;/mo&gt;&lt;mn&gt;12&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;mtext&gt;%&lt;/mtext&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; faster compared to the reference (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;τ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;500&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;). For the dome case for &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;τ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;500&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;9&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, the PBL growth slows down &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;∼&lt;/mo&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;mtext&gt;%&lt;/mtext&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and warms up &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;∼&lt;/mo&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;mtext&gt;%&lt;/mtext&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; slower compared to the reference. In extreme conditions (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;τ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;500&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;5&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;ω&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mn&gt;81&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;) for the stove case we recorded &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;∼&lt;/mo&gt;&lt;mn&gt;62&lt;/mn&gt;&lt;mtext&gt;%&lt;/mtext&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;∼&lt;/mo&gt;&lt;mn&gt;72&lt;/mn&gt;&lt;mtext&gt;%&lt;/mtext&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; increase in PBL growth and heating rates respectively. For the dome case, we recorded &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;∼&lt;/mo&gt;&lt;mn&gt;21&lt;/mn&gt;&lt;mtext&gt;%&lt;/mtext&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mo&gt;∼&lt;/mo&gt;&lt;mn&gt;22&lt;/mn&gt;&lt;mtext&gt;%&lt;/mtext&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt; decreases in PBL growth and heating rates respec","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"352 ","pages":"Article 121192"},"PeriodicalIF":4.2,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143768228","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":"Concentrations, profiles, and risk assessment of organic UV filters in atmospheric PM2.5 from Beijing, China","authors":"Yuwen Deng ,&nbsp;Qianling Yang ,&nbsp;Lirong Gao ,&nbsp;Chi Xu ,&nbsp;Yin Liu ,&nbsp;Ming Xu ,&nbsp;Bin Zhao ,&nbsp;Minghui Zheng","doi":"10.1016/j.atmosenv.2025.121210","DOIUrl":"10.1016/j.atmosenv.2025.121210","url":null,"abstract":"<div><div>Human exposure to organic ultraviolet (UV) filters may pose health risks, but the distribution of UV filters in PM_2.5 of four seasons is currently unknown. In this study, PM_2.5 samples were collected during 2021–2022 in Beijing, and 15 organic UV filters were analyzed. The concentrations of ∑UV filter ranged from 260 to 1859 pg/m³. The highest ∑UV filter concentrations were observed during summer, with temperature showing a significant positive correlation (p &lt; 0.01) on the concentrations of homosalate (HMS), 2-ethylhexyl salicylate (EHS) and Ethylhexyl-4-methoxycinnamate (EHMC). The dominant compounds were HMS, EHS, and EHMC, which accounted for 93.5% of the median contributions. The median concentration of 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV-328) was 0.58 pg/m³, which was lower than that in other studies. It was noteworthy that 2,4-Di-tert-butyl-6-(5-chloro-2H-benzotriazol-2-yl) phenol (UV-327) and 2-(2H-Benzotriazol-2-yl)-6-(butan-2-yl)-4-tert-butylphenol (UV-350) were firstly detected in ambient PM_2.5. In vivo predicted biological toxicity and absorption, distribution, metabolism, and excretion characteristics were assessed, EHMC was prioritized due to its high concentration and high potential to be absorbed by human body. The risks of ∑UV filters through inhalation and dermal contact were negligible for both toddlers and adults, and inhalation exposure exceeded dermal contact by 2–3 orders of magnitude. This is the first study of the occurrence, profiles and risk assessment of 15 UV filters in PM_2.5, and more attention should be paid for prioritized UV filters especially EHMC.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"351 ","pages":"Article 121210"},"PeriodicalIF":4.2,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143748682","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":"Lower atmospheric profiling for climate studies pertaining to aerosols, radiation and turbulence using Unmanned Aerial System in India: Initial results","authors":"Padmakumari B,&nbsp;Sanket Kalgutkar,&nbsp;Mahesh Nikam,&nbsp;Subrata Mukherjee","doi":"10.1016/j.atmosenv.2025.121211","DOIUrl":"10.1016/j.atmosenv.2025.121211","url":null,"abstract":"<div><div>The lower atmosphere close to the Earth's surface, though crucial for various process studies and models, still remained a gap area for a long. The Indian Institute of Tropical Meteorology (IITM) pioneered in collecting aerosol and cloud data using manned aircraft. However, to fill the data gap in the lower atmosphere, IITM envisaged Unmanned Aerial System (UAS) as an innovative aerial platform and the program ‘<em>Lower Atmospheric Research using Unmanned Aerial System Facility (LARUS)</em>’ is instigated to demonstrate the efficacy of a fixed-wing medium size UAS for probing the lower atmosphere for climate studies. The UAS is equipped with lightweight advanced science payload and an isokinetic aerosol inlet, for targeted in-situ measurements of aerosol, chemistry, radiation, turbulence and meteorological parameters (temperature (T) and Relative Humidity (RH)). The vertical profiles on different flight days depicted high vertical diurnal variability of the measured parameters. Comparison of T &amp; RH profiles of INSAT-3DR Sounder and UAS depicted huge data gap in satellite profiles in the lower altitudes. The new approach in our study is obtaining high frequency simultaneous in-situ measurements within the footprint of 5 km with high vertical resolution to study local atmospheric processes.</div><div>The data emphasises elevated absorbing aerosol layers (AAL) or haze layers with maximum absorption up to 500 m above the ground due to local anthropogenic activities. The sample filter papers revealed the type, source and morphology of the observed aerosols. The incoming and reflected (outgoing) shortwave radiation indicated distinct features with an albedo of 0.178 above the haze layer (at 500 m) and 0.017 at the surface and solar absorption of 70 W/m² in the layer 0–500 m. The presence of haze also influenced the turbulence parameters (u, v, w) and Turbulent Kinetic Energy (TKE) at those altitudes. This study demonstrates instrumented UAS for lower atmospheric research, the first of its kind in India, highlighting various results essential for climate studies.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"351 ","pages":"Article 121211"},"PeriodicalIF":4.2,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143748680","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":"Impact of the actinic radiative effect of scattering aerosols on ozone vertical distribution in the Pearl River Delta, China","authors":"Tao Deng ,&nbsp;Shanshan Ouyang ,&nbsp;Xiaoyang Chen ,&nbsp;Guowen He ,&nbsp;Xue Zhang ,&nbsp;Jeremy Cheuk-Hin Leung ,&nbsp;Qing Wang ,&nbsp;Zebiao Zhang ,&nbsp;Yu Zou ,&nbsp;Boru Mai ,&nbsp;Li Liu ,&nbsp;Xuejiao Deng ,&nbsp;TiJian Wang","doi":"10.1016/j.atmosenv.2025.121207","DOIUrl":"10.1016/j.atmosenv.2025.121207","url":null,"abstract":"<div><div>Currently, the Pearl River Delta (PRD) region faces the concurrent issues of aerosol and ozone pollution. Aerosols have a significant impact on the actinic radiative flux, which greatly influences the formation of ozone. This study quantitatively estimates the impact of scattering aerosol actinic radiative effect on the vertical distribution of ozone and secondary pollutants during a double high pollution episode in October 2012 using a localized parameterization formula for aerosol extinction profiles and the Weather Research Forecast–Community Multiscale Air Quality (WRF-CMAQ) model. Scattering aerosols can increase photolysis rates when the Aerosol Optical Depth is low. Aerosol actinic radiative effect reduces ground level ozone and PM_2.5 in the morning. In the core area of the PRD, the reduction in ozone reaches up to 20 ppb, while PM_2.5 decreases by 4–8 μg/m³. But it increases ozone and PM_2.5 levels in the upper and middle layers of the boundary layer during midday and the afternoon, with ozone increasing by 5–20 ppb and PM_2.5 by 1–2 μg/m³. Enhanced oxidizing capacity promotes the generation of sulfate and secondary organic aerosols, further increasing scattering aerosols and forming a positive feedback loop. The acinic radiative effect of aerosols lead to a diurnal variation in the reduction of surface ozone concentration, with a more pronounced effect in the morning. When radiation is weak in the morning and there is sufficient precursor for ozone, changes in radiation have a greater impact on ozone. As radiation becomes stronger, even though aerosols attenuate the radiation, there is still sufficient radiative flux to drive actinic reactions, and the impact of scattering aerosols on surface ozone concentration at midday is not significant. The mechanisms by which aerosol actinic radiative effect influence secondary organic aerosols (SOA) and sulfates are similar to those for ozone described above.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"352 ","pages":"Article 121207"},"PeriodicalIF":4.2,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143776432","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":"El Niño-Southern Oscillation and its impact on population exposure to ozone pollution and heatwave compound events in China","authors":"Lijun Liu ,&nbsp;Youjia Liang ,&nbsp;Tianyu Zhang","doi":"10.1016/j.atmosenv.2025.121209","DOIUrl":"10.1016/j.atmosenv.2025.121209","url":null,"abstract":"<div><div>The El Niño Southern Oscillation (ENSO) has complex effects on human health through ozone pollution and heatwave compound events (OPHW). Although the climatic driving mechanisms of single extreme events in China have been preliminarily confirmed, the nexus of ENSO-OPHW-population exposure risk remains unclear. This study collected Niño 3.4 index, surface O3 and 209 Chinese cities' meteorological station data during the warm seasons (May–October) of 2013–2020, to reveal the effects of the ENSO on the three types of OPHW (ozone pollution-daytime heatwave: OPDH, ozone pollution-nighttime heatwave: OPNH, and ozone pollution-daytime and nighttime compound heatwave: OPCH) and the OPHW risks in major cities in China, via spatiotemporal statistics and geographical and temporal weighted regression (GTWR) modeling. Trend analyses indicate that ozone concentration, temperature, and the co-occurrence days of the three types of OPHW increase at a higher rate during El Niño periods than during La Niña periods. The driving effect of ENSO are found to amplify the OPHW is ranked as follows: ozone concentration (6.1 μg m⁻³) &gt; temperature (1.8 °C) &gt; co-occurrence days (0.2 days). Driven by the position of the subtropical high and anticyclonic changes over the continent, clear skies, high temperatures, low humidity, and low wind speeds significantly influence the three types of compound events. Moreover, during La Niña periods, the anomalous low-level anticyclone shows a significant southward shift compared to El Niño periods. During El Niño periods, the population exposure risk caused by OPHW is generally higher than during La Niña periods. OPDH, OPNH, and OPCH lead to the maximum relative changes of population exposure risk in the middle reaches of the Yangtze River (100 %), Sichuan-Chongqing (44.5 %), and Beijing-Tianjin-Hebei (11.2 %) urban agglomerations, respectively. These findings highlight the need for targeted research on the differential impacts of various compound events on regional population health and ecosystems. This study provides critical insights and methodological support for coordinated responses to extreme event changes and ozone pollution management.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"351 ","pages":"Article 121209"},"PeriodicalIF":4.2,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143748687","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":"Source attribution of near-surface ozone pollution in Jiangsu Province of China over 2013–2019","authors":"Siqi He ,&nbsp;Yang Yang ,&nbsp;Hailong Wang ,&nbsp;Pinya Wang ,&nbsp;Hong Liao","doi":"10.1016/j.atmosenv.2025.121205","DOIUrl":"10.1016/j.atmosenv.2025.121205","url":null,"abstract":"<div><div>Near-surface ozone (O₃) is one of the most severe air pollutants in China, particularly over densely populated Jiangsu Province in the Yangtze River Delta. In this study, an O₃ source tagging technique is utilized in a chemistry-climate model to quantify the source contributions of various emission sectors and regions for nitrogen oxides (NO_x) and volatile organic compounds (VOCs) to O₃ concentrations in Jiangsu Province during 2013–2019. The results show that the near-surface O₃ in Jiangsu Province is mainly contributed by surrounding and remote anthropogenic NO_x emissions through long-range transport. Local anthropogenic NO_x emissions account for only 13 % and 18 % of the annual and summertime mean near-surface O₃ in Jiangsu Province, respectively. Anthropogenic NO_x emissions from the surface transportation, industry, and energy sectors account for 21 %, 22 % and 20 % of the annual mean near-surface O₃ concentration in Jiangsu Province, respectively. Biogenic and anthropogenic VOCs emissions each explains one-third of the annual mean near-surface O₃ concentration in Jiangsu, while methane and stratospheric chemical production contribute 21 % and 6 %, respectively. The sources from stratospheric production, aircraft, lightning, and foreign emissions are the primary contributors to O₃ in the mid- and high troposphere. During high pollution days in Jiangsu Province, the near-surface O₃ concentrations increase with the maximum exceeding 20 ppb, which is attributed to both the enhanced photochemical production and regional transport in favorable meteorological conditions.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"352 ","pages":"Article 121205"},"PeriodicalIF":4.2,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143785459","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":"Inferring near-surface ozone production regimes: Insights from using satellite retrievals over the contiguous US","authors":"Akanksha Singh ,&nbsp;Allison M. Ring ,&nbsp;Hao He ,&nbsp;Dale J. Allen ,&nbsp;Russell R. Dickerson ,&nbsp;Ross J. Salawitch ,&nbsp;Timothy P. Canty","doi":"10.1016/j.atmosenv.2025.121208","DOIUrl":"10.1016/j.atmosenv.2025.121208","url":null,"abstract":"<div><div>Surface ozone regulation policies rely heavily on air quality models, such as CAMx, for guidance. Comparison with observations is crucial to evaluating a model's ability to represent ozone production chemistry. Identifying factors influencing surface ozone formation is complicated because ozone photochemical production rates are non-linearly dependent on concentrations of precursors such as nitrogen oxides (NO_x) and volatile organic compounds (VOCs). We compare ozone production regimes (OPRs) identified from satellite observations and model simulations, as defined by the ratio of column formaldehyde to nitrogen dioxide (FNR, HCHO/NO₂). We performed CAMx simulations for summer 2016 over the Contiguous United States (CONUS) and compared output against two OMI NO₂ and HCHO retrievals. Our analysis spans diurnal and altitudinal variations of OPRs, offering important insights for effective policy formulation. At the time of the OMI overpass oz(∼1:30 p.m. LT), OPR is NO_x-limited over most of the CONUS, as determined from OMI column ratios. Analysis of CAMx column ratios shows similar results. In contrast, more regions are VOC-limited when we constrain our ratio to within the Planetary Boundary Layer (PBL). In the morning (∼9 a.m. LT), the CAMx PBL column ratios shift towards VOC-limited regime compared to the afternoon. We highlight areas of the CONUS where satellite measurements of FNR may not be an accurate indicator of near-surface OPRs. Air quality regulations based on satellite observations should consider the diurnal variations of surface OPRs and assess how well their ratios represent near-surface OPR. Our results have implications for interpretation of TEMPO data for policy relevant applications.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"352 ","pages":"Article 121208"},"PeriodicalIF":4.2,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792659","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":"Heterogeneous reactions of toluene/NO2/NH3 on α-Fe2O3/α-Al2O3 particles: The effects of pollutant content and temperature changes on the formation of N-containing organic compounds (NOCs)","authors":"Sijie Wen ,&nbsp;Xiang He ,&nbsp;Aiyilaiti Kudesi ,&nbsp;Shuangxi Wang ,&nbsp;Xin Liu ,&nbsp;Mingsong Dong ,&nbsp;Xiaolong Yu","doi":"10.1016/j.atmosenv.2025.121195","DOIUrl":"10.1016/j.atmosenv.2025.121195","url":null,"abstract":"<div><div>Heterogeneous reactions of toluene with mineral oxides play a crucial role in the formation processes of N-containing organic compounds (NOCs). However, less attention was paid to the effects of pollutant content and temperature changes on the formation of NOCs under combined pollution. In this study, the combined effects on the heterogeneous reaction of toluene/NO₂/NH₃ with α-Fe₂O₃/α-Al₂O₃ particles were investigated by using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The results show that the characteristic peak of the R-ONO₂ group appears at 1295 cm⁻¹, indicating benzyl nitrate formation in the presence of α-Fe₂O₃ with or without α-Al₂O₃. The addition of α-Al₂O₃ promotes the R-ONO₂ formation on the particle surface compared to pure α-Fe₂O₃ as a result of the dispersion and oxidation of the additional particles. The optimal mass ratio of α-Fe₂O₃ and α-Al₂O₃ particles is 3:1. Furthermore, the optimal concentration ratio for toluene, NO₂ and NH₃ is determined as 2.5:2.5:1. It is obvious that NO₂ and toluene are the primary sources of organic nitrates production. Higher concentration proportions of NO₂ and toluene within a certain range lead to higher formation amounts of NOCs during the heterogeneous reaction. Spectral analysis demonstrates that reaction kinetics, such as reaction rate and uptake coefficient, are sensitive to temperature variations. When temperature decreases from 298 K to 253 K, the reaction rate increases from (1.59 ± 0.04) × 10¹⁸ ions g⁻¹ s⁻¹ to (2.38 ± 0.02) × 10¹⁸ ions g⁻¹ s⁻¹. Low temperature favors the production of R-ONO₂, resulting from an exothermic process during the heterogeneous reaction. These findings are helpful for further exploring the combined effects on particulate NOCs formation and partly contribute to understanding of multicomponent reaction systems in real environment conditions.</div></div>","PeriodicalId":250,"journal":{"name":"Atmospheric Environment","volume":"351 ","pages":"Article 121195"},"PeriodicalIF":4.2,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143734507","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}