Atmospheric Chemistry and Physics最新文献

{"title":"Simulated reductions in heterogeneous isoprene epoxydiol reactive uptake from aerosol morphology in the contiguous United States using the Community Multiscale Air Quality Model (CMAQv5.3.2)","authors":"Sara L. Farrell,Quazi Z. Rasool,Havala O. T. Pye,Yue Zhang,Ying Li,Yuzhi Chen,Chi-Tsan Wang,Haofei Zhang,Ryan Schmedding,Manabu Shiraiwa,Jaime Green,Sri H. Budisulistiorini,Jose L. Jimenez,Weiwei Hu,Jason D. Surratt,William Vizuete","doi":"10.5194/acp-26-13557-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13557-2026","url":null,"abstract":"Aerosol particles contain complex mixtures of polar and non-polar species that can undergo organic-inorganic phase separation. In phase-separated aerosol particles, the phase state of the outer organic coating can modulate heterogeneous chemistry. Heterogeneous chemistry leading to isoprene epoxydiol (IEPOX)-derived secondary organic aerosol (IEPOX-SOA) is encoded in the Community Multiscale Air Quality (CMAQ) model and has been the focus of previous aerosol phase separation and phase state work. In a previous study, a constant ratio of water in the organic coating ( w s ) was assumed in modeling phase separation and state. Recent studies, however, have highlighted w s as an important modulator of phase state. This work uses a later CMAQ version (version 5.3.2) with capabilities to model dynamic water uptake to the organic coating – to better predict w s and its impact on the organic coating phase state. In addition, new parameterizations for estimating organic aerosol phase state were encoded into CMAQ, and were compared with respect to their impacts on phase state and IEPOX-SOA predictions. These evaluations were completed simulating a summertime episode over the continental United States. Simulated diurnal profiles of aerosol phase state agreed within one standard deviation of observationally-derived field measurements. The implementation of phase separation and phase state parameterizations resulted in times and grid cells where IEPOX reactive uptake is completely suppressed. While modelled positive bias in 2-methyltetrol concentrations were decreased with phase separation and phase state updates, modelled methyltetrol sulfates and total IEPOX-SOA concentrations further underpredicted field observations in comparison to Base CMAQ.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"14 1","pages":"13557-13579"},"PeriodicalIF":6.3,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149049776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of aerosol iron (Fe) solubility using global dataset – Part 1: Mechanisms underlying the inverse relationship between Fe solubility and Fe concentration","authors":"Kohei Sakata,Minako Kurisu,Yoshio Takahashi","doi":"10.5194/acp-26-13505-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13505-2026","url":null,"abstract":"Atmospheric deposition of aerosol iron (Fe) can stimulate marine primary productivity by supplying dissolved Fe (d-Fe) to the surface ocean, thereby potentially influencing the global climate. Aerosol Fe solubility (Fe sol %) is closely linked to its bioavailability, and previous studies have shown that Fe sol % generally increases as aerosol Fe concentration decreases. However, the mechanism underlying this widely observed inverse relationship remains unresolved. In this study, aerosol observations from East Asia, the North and South Pacific, and the Atlantic were compiled, and the enrichment factor of total Fe (EF T-Fe = (T-Fe / T-Al)aerosol/ (T-Fe / T-Al) crust ) and dissolved Fe to dissolved Al ([d-Fe] / [d-Al]) were used to estimate the contributions of mineral-derived and anthropogenic Fe to aerosol d-Fe, as well as the Fe sol % of each source fraction. Aerosol d-Fe was found to be derived predominantly from mineral dust in many oceanic regions. In addition, both mineral-derived Fe and anthropogenic Fe showed inverse relationships between concentration and solubility. If the inverse relationship between Fe concentration and Fe sol % were controlled mainly by simple two-component mixing between low-solubility mineral particles and highly soluble anthropogenic Fe, the Fe sol % of each source fraction would not be expected to vary systematically with concentration. Instead, the results suggest that atmospheric chemical processing, together with depositional removal during transport, progressively increases the solubility of Fe remaining in aerosol particles. The ability to estimate the sources and dissolution processes of aerosol Fe from such fundamental concentration data may help improve the parameterization of aerosol Fe dissolution in global climate models.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"59 1","pages":"13505-13529"},"PeriodicalIF":6.3,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149049778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The dynamics and atmospheric impact of fire-induced circulations in idealised large-eddy simulations inspired by the Santa Coloma de Queralt fire","authors":"Tristan Roelofs,Marc Castellnou,Jordi Vilà-Guerau de Arellano,Martin Janssens,Chiel van Heerwaarden","doi":"10.5194/acp-26-13531-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13531-2026","url":null,"abstract":"We studied the factors governing the existence of fire-induced circulations ahead of the flaming zone and the impact of these circulations on the thermodynamic structure of the atmospheric boundary layer. To study the circulation, we used MicroHH to create a high-resolution (25 m) turbulence-resolving 3D large-eddy simulations (25.6 km×38.4 km) of a stationary fire under realistic atmospheric conditions. The setup was inspired by field observations of fire characteristics and a radiosonde from the Santa Coloma de Queralt fire (Catalonia, Spain, 24 July 2021). The stationary fire enabled us to isolate the persistent impacts of the fire on the atmosphere. Our results indicate that the existence of a fire-induced circulation is governed by the wind speed component aligned with the circulation. In our simulations, the circulation consisted of updrafts above the fire, downdrafts 2 km ahead, and reversed surface winds between the updrafts and downdrafts. With higher wind speeds in the direction of the circulation, the reversal of the surface winds decreases. Consequently, the circulation dissipates, since the reversed winds connect the updrafts and downdrafts into a circulation. Hence, explaining why fire-induced circulations are not always present. The thermodynamic impact of the circulation is driven by the updrafts and downdrafts, causing 2 km of deepening, followed by 2 km of thinning of the atmospheric boundary layer ahead of the fire. Future research with non-stationary fires is required to quantify the impact of the modified thermodynamics and wind patterns on fire behaviour.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"5 1","pages":"13531-13555"},"PeriodicalIF":6.3,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149049777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First observations of solar zenith angle modulation of diurnal tidal structure in the MLT region","authors":"Wen Yi,Jianyuan Wang,Xianghui Xue,Chengyun Yang,Iain M. Reid,Robert A. Vincent,Andrew MacKinnon,Damian J. Murphy,Njål Gulbrandsen,Masaki Tsutsumi,Baiqi Ning,Guozhu Li,Nicholas J. Mitchell,Tracy Moffat-Griffin,Toshitaka Tsuda,Haiying Li,Paulo P. Batista,Jianfei Wu,Tingdi Chen,Xiankang Dou","doi":"10.5194/acp-26-13441-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13441-2026","url":null,"abstract":"A global climatology of diurnal tides in the mesosphere and lower thermosphere (MLT) is constructed using multiyear observations from fifteen meteor radars distributed worldwide. The results show that diurnal tidal amplitudes are strongest at low and mid-latitudes (10–50° N/S), with peak values of about 60 m s −1 near 20–30° N/S, and are comparatively weak near the Equator and at polar latitudes. The seasonal variations of the diurnal tide are characterized by maxima around the equinoxes and minima during the solstices. In addition to these global climatological features, we identify a clear modulation of the vertical structure of diurnal tidal amplitude and phase by seasonal variations in solar forcing, represented here by the solar zenith angle (SZA). This modulation is particularly evident at northern low and mid-latitudes, but is much weaker in the Southern Hemisphere. The hemispheric asymmetry suggests that the tidal response to solar forcing is not globally uniform. To further explore the possible cause of this asymmetry, we examine the meridional fluxes of zonal tidal momentum. The results suggest that background zonal winds can influence tidal propagation through filtering effects and momentum drag, thereby contributing to the observed hemispheric differences in tidal structure. These results provide new observational evidence for the coupling between solar forcing and diurnal tides in the MLT region and offer useful constraints for the evaluation of general circulation models. They also improve our understanding of tidal propagation and variability in the middle and upper atmosphere.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"57 1","pages":"13441-13462"},"PeriodicalIF":6.3,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149050117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On spatial scales of local aerosol production in boreal ecosystems","authors":"Ekaterina Ezhova,Üllar Rannik,Santeri Tuovinen,Olga Garmash,Otso Peräkylä,Piaopiao Ke,Topi Laanti,Janne Lampilahti,Markus Lampimäki,Anna Lintunen,Veli-Matti Kerminen,Janne Rinne,Timo Vesala,Markku Kulmala","doi":"10.5194/acp-26-13463-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13463-2026","url":null,"abstract":"Quantification of the climate impact of land use is important for the development of effective climate change mitigation and adaptation practices. Ecosystems emit compounds that participate in the formation and growth of aerosol particles. Particles of few nm size can be produced locally as compared to regional aerosol growth processes at larger sizes, and in boreal environment, higher concentrations of small particles were observed over agricultural lands than over forests. The aim of this study is to provide estimates of spatial scales of an ecosystem needed to produce small particles predominantly from its own emissions. Here, we consider forest and agricultural ecosystems in the boreal region, and distinguish situations in which aerosol production is relatively slow and vertically distributed within the well-mixed convective boundary layer and when it can occur quickly close to the surface. For the latter, we introduce source contribution function of local aerosol production, which is based on the concentration footprint function modified to account for aerosol growth. We quantify the contributing area for neutral stratification and a typical wind speed. For below-canopy air layer in the forest at 0.5–4 m height from the surface, the relevant distance is at 100–500 m, depending on the growth rate and the initial size distribution. Under the same conditions in the agricultural field, the contribution of the nearby 100–500 m is up to 30 % while the total contributing area is at 0.9–5.5 km. To improve estimates, more research is needed on the dynamics of small aerosol, including contributions of chemical compounds to aerosol growth and the impact of meteorological conditions.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"17 1","pages":"13463-13483"},"PeriodicalIF":6.3,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149049814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Secondary ice production within shallow, mixed-phase clouds in cold air outbreaks over the Labrador Sea","authors":"Michael Biggart,Thomas W. Choularton,Martin W. Gallagher,Keith N. Bower,Gary Lloyd,Paul J. Connolly,Benjamin J. Murray,Mark D. Tarn,Erin N. Raif,Steven J. Abel","doi":"10.5194/acp-26-13401-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13401-2026","url":null,"abstract":"Shallow, mixed-phase clouds within marine cold air outbreaks (CAOs) frequently form over the North Atlantic. Their shortwave radiative effect is modulated as stratocumulus decks break up into cumulus clouds to the south. Microphysical processes controlling their phase remain poorly represented by climate models; of these, secondary ice production (SIP), describing mechanisms producing new ice crystals from existing primary ice, is a major contributor to uncertainties in the mixed-phase cloud response to future warming. We examine in-situ measurements of cloud microphysical properties made using the UK FAAM BAe-146 research aircraft within CAOs over the Labrador Sea as part of the October–November 2022 M-Phase field campaign. Measured ice particle concentrations frequently exceeded ice-nucleating particle (INP) concentrations at all in-cloud temperatures, highlighting the importance of SIP in these clouds. Peak ice concentrations were observed within the Hallett–Mossop (H–M) process temperature range (−3 to −8 °C), four orders of magnitude above expected INP concentrations. SIP regions contained large, rimed columns and graupel mixed with smaller columnar crystals (< 200 µm), indicative of the H–M process. Splinter production rate calculations indicated the H–M process could feasibly account for most ice production in the largest ice enhancement regions. A secondary zone of SIP activity, between −15 and −18 °C, comprised fragile, branched crystals, aggregates and ice fragments, consistent with laboratory studies of ice-ice collisional breakup. SIP amplified across the stratiform-to-convective regime transition, favouring weak-to-moderate updrafts (0 to +2 m s −1 ) containing high concentrations of large liquid droplets, suggesting regime-aware SIP schemes would benefit future CAO modelling.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"23 1","pages":"13401-13439"},"PeriodicalIF":6.3,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149050118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Consistency between zonal mean stratospheric and total column ozone trends (2000–2024)","authors":"Brian Auffarth,Mark Weber,Alexei Rozanov,Carlo Arosio,John P. Burrows,Melanie Coldewey-Egbers,Sean M. Davis,Doug Degenstein,Kimberlee Dubé,Stacey M. Frith,Lucien Froidevaux,Diego Loyola,Vitali E. Fioletov,Viktoria Sofieva,Ronald van der A,Jeannette D. Wild","doi":"10.5194/acp-26-13359-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13359-2026","url":null,"abstract":"This study presents an updated assessment of stratospheric and total column ozone trends over the 2000–2024 period using six merged limb-profile datasets and six merged total ozone datasets. Long-term changes were quantified using a multiple linear regression framework that accounts for dynamical and chemical variability. In addition to standard regressors (solar cycle, QBO, ENSO, stratospheric aerosol optical depth), we include Arctic and Antarctic Oscillation indices and the eddy heat flux in each hemisphere as proxies for dynamic variability. Volcanic (and wildfire) aerosol forcing is represented by separate proxies for three periods dominated by the major volcanic events of El Chichón, Pinatubo, and post-2000 volcanic eruptions, including Hunga-Tonga. These period-specific proxies are employed to better account for varying dynamical ozone responses that largely depend on the season and location of the eruptions. All profile datasets consistently show positive trends in the upper stratosphere, with the strongest ozone recovery in southern mid-latitudes, in agreement with other studies. In the lower stratosphere, trends remain weak, spatially heterogeneous, and predominantly negative. A comparison of stratospheric column trends derived from profile data with total ozone trends shows close agreement across all latitude bands. Within the trend uncertainties, total column trends since 2000 are largely driven by stratospheric ozone changes, while tropospheric contributions to zonal-mean total ozone trends (the difference between total and stratospheric column trends) appear negligible. The extended regression framework improves the representation of recent dynamical variability and provides an updated perspective on stratospheric ozone recovery through 2024.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"28 1","pages":"13359-13386"},"PeriodicalIF":6.3,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149021834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complexation strength between organic carbon and transition metal ions dominates the photochemical conversion of SO\u0000 2\u0000 to sulfates","authors":"Shaojie Yang,Shiwei Lai,Jianwei Zheng,Hao Na,Fu Li,Wangjin Yang,Chong Han","doi":"10.5194/acp-26-13387-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13387-2026","url":null,"abstract":"The photooxidation of SO 2 on organic carbon (OC) is a critical pathway for sulfate formation, yet the role of interactions between OC and transition metal ions (TMIs) in this process remains scarcely understood. We systematically investigated potential influences of TMIs (Fe 3+ , Cu 2+ and Mn 2+ ) on the conversion of SO 2 to sulfates on OC from coal combustion under irradiation. For OC and its coexistence with TMIs under experimental conditions adopted here, the steady-state uptake coefficients of SO 2 and sulfate masses were (0.39–22.24) × 10 −6 and (2.36–26.05) × 10 −3 mg, respectively. Fe 3+ exhibited a significantly antagonistic effect, whereas Cu 2+ and Mn 2+ enhanced SO 2 uptake and sulfate generation on OC. Spectroscopic evidences, including absorbance decreasing and fluorescence quenching, confirmed the complexes formation of TMI with chromophores in OC. Fe 3+ owned the strongest binding affinity with chromophores, followed by Cu 2+ and Mn 2+ . This variation in the coordination strength dominated the generation of reactive species, such as free electrons (e − ), superoxide radicals (⚫O2-), H 2 O 2 and hydroxyl radicals (⚫OH), and ⚫OH acted as a pivotal trigger to drive the sulfate production. Extended investigations confirmed a good linear relationship between ⚫OH intensity ( I ) and sulfate mass ( M sulfates ): M sulfates  = (1.68 ± 0.11) × 10 −2  ×  I  − (0.43 ± 0.08) × 10 −2 , demonstrating that the regulatory effects of metal ions on the sulfate production were generally governed through their ability to suppress or facilitate the ⚫OH generation.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"17 1","pages":"13387-13400"},"PeriodicalIF":6.3,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149021835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Cold-Air Outbreaks in the Marine Boundary Layer Experiment model-observation intercomparison project (COMBLE-MIP) – Part 1: Model specification, observational constraints, and preliminary findings","authors":"Timothy W. Juliano,Florian Tornow,Ann M. Fridlind,Andrew S. Ackerman,Gregory S. Elsaesser,Bart Geerts,Christian P. Lackner,David Painemal,Israel Silber,Mikhail Ovchinnikov,Gunilla Svensson,Michael Tjernström,Peng Wu,Alejandro Baró Pérez,Peter Bogenschutz,Dmitry Chechin,Kamal Kant Chandrakar,Jan Chylik,Andrey Debolskiy,Rostislav Fadeev,Anu Gupta,Luisa Ickes,Michail Karalis,Martin Köhler,Branko Kosović,Peter Kuma,Weiwei Li,Evgeny Mortikov,Hugh Morrison,Roel A. J. Neggers,Anna Possner,Tomi Raatikainen,Lea Raillard,Sami Romakkaniemi,Niklas Schnierstein,Shin-ichiro Shima,Nikita Silin,Mikhail Tolstykh,Étienne Vignon,Lulin Xue,Meng Zhang,Xue Zheng","doi":"10.5194/acp-26-13267-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13267-2026","url":null,"abstract":"Models struggle to represent the coupled microphysical, turbulent and radiative processes within widespread, long-lived marine cold-air outbreak (CAO) cloud fields, contributing to forecast and climate biases. Here we combine ground-based and satellite measurements to initialize and constrain large-eddy simulations (LES) of cloud field evolution with distance downwind from the marginal ice zone during a strong, highly supercooled and convective CAO observed during the Cold-Air Outbreaks in the Marine Boundary Layer Experiment (COMBLE). LES results are compared with large-scale models run in single-column model (SCM) mode, providing an observation-constrained framework for large-scale model evaluation and future improvements. All models reproduce rapid cloud formation off the ice edge, and a monotonic ascent of downwind cloud-top heights, closely linked with time-integrated surface heat fluxes. LES generally reproduce domain-mean observational targets using a modest test domain (25×25 km 2 ), and a larger domain (125×125 km 2 ) enables better reproducing the observed growth of convective cell sizes. In realistic mixed-phase LES compared with liquid-only simulations, ice processes lead to thinner, broken cloud decks and substantially reduced cloud radiative effects on top-of-atmosphere longwave fluxes. By contrast, mixed-phase SCM simulations generally underpredict the radiative impact of ice, primarily owing to insufficient reduction of cloud cover. Results indicate that cellular cloud structure is qualitatively captured by LES, and thus LES could provide guidance to improvement of large-scale model physics schemes. Follow-on work will extend these results to larger domains, apply objective analysis of mesoscale structure, and include prognostic aerosol properties for droplet and heterogeneous ice formation.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"78 1","pages":"13267-13302"},"PeriodicalIF":6.3,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149021839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scenario-driven ozone projections and associated impact on mortality over Africa with an integrated machine learning framework","authors":"Huimin Li,Yang Yang,Hailong Wang","doi":"10.5194/acp-26-13341-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13341-2026","url":null,"abstract":"Ozone (O 3 ), a major tropospheric air pollutant, poses significant threats to public health and ecosystems, especially across Africa, where O 3 concentrations have experienced pronounced increases in recent decades. This study employs an interpretable machine learning (ML) model integrated with multi-source data to predict near-surface O 3 levels over Africa from 2020 to 2050 driven by climate change under four Shared Socioeconomic Pathways (SSPs). We quantitatively investigate the respective roles of climate-driven changes in meteorological conditions and biogenic isoprene emissions in affecting future O 3 variations. Results reveal that, in an annual mean sensitivity experiment that isolates climate-driven changes in biogenic isoprene, increased biogenic isoprene emissions contribute to a slight reduction in O 3 levels (<0.5 ppb). Conversely, favorable meteorological conditions elevate O 3 levels over Africa, with a maximum projected increase of 2.0 ppb in 2050 relative to 2020, dominating the O 3 variations driven by climate change. The low-emission SSP scenarios are projected to lead to smaller increases in O 3 levels than the high-emission SSPs. Moreover, elevated air temperatures associated with global warming magnify the health burden across Africa, as O 3 pollution acts as an additional stressor in a warming climate. This highlights the urgency for robust air pollution control and climate mitigation strategies to alleviate future health impacts in Africa.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"100 1","pages":"13341-13357"},"PeriodicalIF":6.3,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149021838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}