Atmospheric Chemistry and Physics最新文献

{"title":"Cross-phase partitioning of sulfur-nitrogen ratios and aerosol mixing-state evolution based on single-particle observations","authors":"Yuan Dai,Junfeng Wang,Mindong Chen,Su Zhang,Haiwei Li,Yunjiang Zhang,Yun Wu,Ming Wang,Xinlei Ge","doi":"10.5194/acp-26-14015-2026","DOIUrl":"https://doi.org/10.5194/acp-26-14015-2026","url":null,"abstract":"The balance between sulfur and nitrogen (S-N) precursors influences secondary aerosol formation, yet its cross-phase links to particle composition and mixing states remain poorly constrained. Here, we integrated single-particle aerosol mass spectrometry (SPA-MS) with pollutant and meteorological observations during winter and summer emission control periods (ECPs) and corresponding normal periods (NPs) in Yangzhou, eastern China. By establishing gas-phase (gSNR), particle-phase (pSNR), and number-based (nSNR) sulfur-to-nitrogen ratio metrics, we combined causal inference with interpretable machine learning to analyze the underlying drivers. During ECPs, reduced NO x emissions alongside relatively stable SO 2 concentrations elevated gSNR, driving an average ∼ 57 % increase in pSNR across particle classes and a 27 % expansion in mean vacuum aerodynamic diameter ( D va ) relative to NPs. Causal analysis revealed a stepwise propagation of S-N partitioning running sequentially from gas-phase precursors to single-particle chemistry and ultimately to the population mixing state. Particle-resolved chemistry demonstrated that pSNR enrichment was highest in particles containing both black carbon and organic carbon, but markedly lower in BC-free inorganic particles, indicating strong particle-type-dependent aging pathways. Relative humidity (RH) acted as a primary regulator of this cross-phase coupling: below 55 % RH, the SNR metrics decoupled, maintaining substantial chemical heterogeneity across particle classes (externally mixed state); above 85 % RH, aerosol liquid water uptake accelerated gas-particle exchange and multiphase processing, causing the SNR metrics to converge as aerosols evolve toward an internally mixed state. These findings suggest that future air-quality models would benefit from incorporating particle-type heterogeneity and humidity-dependent multiphase processes under shifting emission regimes.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"26 1","pages":"14015-14029"},"PeriodicalIF":6.3,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149088021","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":"Driving mechanisms for subsiding shells in simulations of deep moist convection","authors":"Quinlan R. Mulhern,John M. Peters,Jake P. Mulholland","doi":"10.5194/acp-26-13959-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13959-2026","url":null,"abstract":"Downdrafts play an essential role in the feedback between convective clouds and their surrounding environment, and they must be properly accounted for in cumulus parameterizations (CPs). The mechanisms for downdraft formation are often debated in past literature and inconsistently represented in CPs. To address this uncertainty, we investigate the ring of descent surrounding cloudy updrafts known as a subsiding shell, a leading contributor to downdraft mass flux. We analyze two LES of deep convection in the Amazonian dry and wet season, using composite soundings from the Green Ocean Amazon Campaign. The dry and wet season soundings differ in their middle tropospheric relative humidity (RH), which facilitates an assessment of the influence of RH on shell strength. Kinetic energy budgets along trajectories reveal that shells acquire their descent from evaporatively driven negative effective buoyancy along cloud edge and downward oriented dynamic pressure accelerations associated with the toroidal circulations of updraft thermals. Consistent with observations, shell downdrafts were strongest in the dry season simulation. Contrary to hypotheses which attributed this difference to greater evaporative cooling, we find that dry season shell downdrafts associated with deep convection were stronger because of larger dynamic pressure accelerations in the dry season. However, when investigating cumulus congestus clouds, negative effective buoyancy accelerations become increasingly important relative to pressure accelerations. The stronger accelerations in deep convective shells were attributed to stronger dry season updrafts, and consequently more intense toroidal circulations within thermals. Our results provide a foundation of understanding for future improvement of downdraft representation in CPs.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"42 1","pages":"13959-13982"},"PeriodicalIF":6.3,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149088025","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":"Impacts of mesoscale atmospheric subsidence on cloud glaciation and decoupling in Arctic marine cold air outbreaks","authors":"Fiona Paulus,Joshua J. Müller,Benjamin Kirbus,Harald Sodemann,Lars van Gelder,Andreas Walbröl,Manfred Wendisch,Roel A. J. Neggers","doi":"10.5194/acp-26-13983-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13983-2026","url":null,"abstract":"The impact of mesoscale vertical atmospheric motion on the thermodynamic, microphysical, and convective transformations of air masses during marine cold air outbreaks (MCAOs) is largely unknown, partly due to scarcity of suitable observations in Arctic regions. To help close this gap, this study investigates the effects of mesoscale subsidence on the evolution of atmospheric boundary-layer (ABL) properties, cloud phase, and precipitation characteristics for a case study of a shallow MCAO observed in the Fram Strait during the HALO–(𝒜𝒞) 3 campaign in March 2022. Quasi-Lagrangian Large-Eddy Simulations (LES) are conducted with observational initialisation and larger-scale forcing, based on airborne in-situ and remote-sensing measurements. The LES control simulation accurately reproduces the measured thermodynamic ABL structure and the temporal evolution of the observed air mass moving over the Arctic sea ice onto the open ocean. Specifically, the measured ABL height, integrated water vapour, and cloud water paths are well represented by the LES control run. Sensitivity experiments using the LES assuming prescribed subsidence reveal that weaker subsidence substantially deepens the ABL and causes an earlier onset of cloud glaciation. Decoupling of the cloud layer occurs sooner under weaker mesoscale subsidence, triggering convective graupel formation. This link between glaciation and decoupling explains the typical evolution of the cloud liquid water path observed in many MCAOs.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"11 1","pages":"13983-14014"},"PeriodicalIF":6.3,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149088024","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":"Fire carbon emission constraints from space-based carbon monoxide retrievals during the 2019 intense burning season in Brazil","authors":"Anne-Wil van den Berg,Joram J. D. Hooghiem,Auke M. van der Woude,Pieter Rijsdijk,Roland Vernooij,Santiago Botía,Guido R. van der Werf,John B. Miller,Ingrid T. Luijkx,Maarten C. Krol,Wouter Peters","doi":"10.5194/acp-26-13929-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13929-2026","url":null,"abstract":"In 2019, Brazil experienced an intensive fire season, despite the absence of major climate anomalies to enhance fire activity. Existing carbon monoxide (CO) emission estimates from state-of-the-art fire emission inventories differ by a factor two for the period and region. We provide a top-down estimate on CO emissions from these fires using the new CarbonTracker Europe – Long-Window/Short-Window (CTE-LW/SW) inverse modelling framework driven by column-averaged dry air CO mole fractions ( X CO ) from the MOPITT and TROPOMI satellite instruments. Our analysis indicates that the 2019 fires in Brazil released approximately 47 TgCO. Although structural atmospheric-chemistry related uncertainties remain (±15 TgCO), the inversions converged strongly to a common posterior (46–48 TgCO) independent of the prior emission inventory (GFED5.1, GFAS v1.2) or assimilated dataset (TROPOMI, MOPITT). Posterior fire emissions closely resemble the newly released GFED5.1, supporting recent advances in bottom-up fire modelling. Nonetheless, at the biome level, our results reveal a systematic underestimation – by roughly a factor of two – in the Cerrado and Caatinga savannas relative to both fire emission priors. While more targeted uncertainty assessments are required, we speculate that this emission gap unlikely stems from inversion choices alone and may indicate an underestimation of fuel loads or emission factors. Overall, we demonstrate CTE-LW/SW effectively leverages X CO to complement existing fire emission monitoring capacities at increasingly fine spatial resolution – a capability that is especially valuable in Brazil, where different fire regimes occur in close proximity and fire activity has intensified in recent years.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"10 1","pages":"13929-13958"},"PeriodicalIF":6.3,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149088022","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":"Sensitivity of dynamic aging on the climate effects of black carbon aerosols over East Asia in summer","authors":"Peng Gao,Bingliang Zhuang,Yaxin Hu,Yinan Zhou,Runqi Zhao,Qianqian Wang,Shu Li,Tijian Wang,Mengmeng Li,Min Xie","doi":"10.5194/acp-26-13861-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13861-2026","url":null,"abstract":"The climate effects of black carbon (BC) remain highly uncertain, and one critical process that requires accurate representation in climate models is BC aging. This study implements a dynamic aging scheme, which accounts for both condensation and coagulation processes, into the regional climate and chemistry coupled model RegCM-Chem to evaluate the BC climate effects over East Asia in summer. Results indicate that in heavily polluted regions such as the North China Plain and the Sichuan Basin, the BC aging timescale is shorter than 10 h, promoting the formation and wet deposition of hydrophilic BC, which reduces the BC column burden over East Asia by an average of 0.12 mg m −2 . Conversely, BC surface concentrations and optical depth exhibit an increase over eastern China due to the compensation of reduced dry deposition. The strengthened BC direct effects favor the development of the East Asian summer monsoon and enhance moisture convergence and cloud fraction in southern China. Additionally, accelerated aging also promotes increases in cloud droplet number concentrations and cloud optical depth. Under the dynamic aging scheme, the effective radiative forcing at the top of the atmosphere over East Asia due to BC–radiation interactions, BC–cloud interactions and BC–radiation–cloud interactions are +3.60, −0.58 and +0.90 W m −2 , respectively. The climate effects of BC exhibit pronounced nonlinearity driven by adjustments in circulation and cloud. Overall, BC induces a much drier and warmer surface in northern China, whereas southern China experiences the opposite effect.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"5 1","pages":"13861-13884"},"PeriodicalIF":6.3,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149092306","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":"Synthesis of the tethered balloon system and other TRACER campaign measurements elucidates aerosol property profiles","authors":"Fan Mei,Jian Wang,Israel Silber,Nurun Nahar Lata,Gregory W. Vandergrift,Jing Li,Bo Chen,Sarah D. Brooks,Michael P. Jensen,Min Deng,Damao Zhang,Darielle Dexheimer,Beat Schmid,Zezhen Cheng,Swarup China","doi":"10.5194/acp-26-13885-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13885-2026","url":null,"abstract":"Coastal urban environments exhibit strong vertical and horizontal heterogeneity in aerosol properties, complicating process-level understanding of aerosol–cloud interactions. This study analyzes tethered balloon system (TBS) measurements from 149 flights during summer over the greater Houston, Texas, region as part of the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Tracking Aerosol Convection interactions ExpeRiment (TRACER) campaign. We characterized the vertical structure of aerosol number concentrations, size distributions, and inferred cloud condensation nuclei (CCN) concentrations. Air mass history was classified using back-trajectory analysis and k -means clustering into three clusters: (1) marine-influenced, (2) mixed marine and urban emissions, and (3) urban/anthropogenic and long-range transported aerosols. CCN concentrations are estimated from observed size distributions using κ -Köhler theory. The resulting profiles show pronounced vertical variability across clusters, strongly modulated by boundary-layer depth and coastal circulations, leading to substantial variability in the aerosol population available for cloud activation. The marine cluster showed the lowest concentrations, with CCN at 0.8 % supersaturation below 1000 cm −3 , while urban and mixed clusters displayed higher concentrations and more complex layering. Profiles influenced by the mixed marine–urban cluster frequently exhibit decoupling between near-surface aerosol and elevated layers, including enhanced accumulation-mode number aloft, consistent with prior TBS-based compositional studies. A 6–7 September 2022 case study demonstrates that mesoscale transport can simultaneously transform the thermodynamic environment and the aerosol population, highlighting the importance of constraining boundary-layer dynamics and airmass origins before attributing cloud changes to aerosol effects in complex coastal environments.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"54 1","pages":"13885-13908"},"PeriodicalIF":6.3,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149092304","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":"Consistent estimates of carbonyl sulfide and methane stratospheric lifetimes retrieved from AirCore profiles at different latitudes","authors":"Alessandro Zanchetta,Steven van Heuven,Rigel Kivi,Michel Ramonet,Andreas Engel,Maarten Krol,Huilin Chen","doi":"10.5194/acp-26-13909-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13909-2026","url":null,"abstract":"Stratospheric loss is a major sink for both carbonyl sulfide (COS) and methane (CH 4 ), but their stratospheric lifetimes and sinks remain poorly constrained because high-resolution observations of their vertical distributions in the lower stratosphere are sparse. Here, we estimate the mean stratospheric lifetime and sink of COS and CH 4 from their correlations with N 2 O using two distinct methods applied to AirCore vertical profile measurements from three Northern Hemisphere summer campaigns. From these profiles, we derive a COS stratospheric lifetime of 69–90 years, corresponding to a sink of 30–41 GgS yr −1 . For CH 4 ,we find a stratospheric lifetime of 149–168 years, corresponding to a sink of 23–26 TgC yr −1 . These values are in good agreement with previous estimates (39–76 years for COS, 152–160 years for CH 4 ) and with estimates based on ACE-FTS observations (75–76 years for COS, 146–172 years for CH 4 ). As has been noted previously, we also find a decline in the COS tropospheric burden between 2016 and 2020 in our AirCore samples, in contrast to the continued growth of CH 4 and N 2 O. In addition, we found that tracer-tracer correlations vary among flights, and even within the same campaign, pointing to variability in lower-stratospheric composition. Although this variability may reflect differences in stratospheric transport, its origin remains unclear and requires further investigation. These results provide observational constraints on the stratospheric budgets of COS and CH 4 and help refine their representation in atmospheric chemistry and transport models.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"4 1","pages":"13909-13927"},"PeriodicalIF":6.3,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149088027","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":"Uncertainties in recent tropical stratospheric and tropospheric ozone changes limit the use of observational constraints for assessing future ozone change","authors":"Sean M. Davis,William T. Ball,Yue Jia,Gabriel Chiodo,Justin A. Alsing,James Keeble,Hideharu Akiyoshi,Carlo Arosio,Ewa M. Bednarz,Andreas Chrysanthou,Melanie Coldewey-Egbers,Robert Damadeo,Sandip Dhomse,Mohamadou A. Diallo,Simone Dietmuller,Roland Eichinger,Stacey Frith,Birgit Hassler,Michaela I. Hegglin,Daan Hubert,Patrick Jöckel,Béatrice Josse,Natalya Kramarova,Diego Loyola,Eliane Maillard Barras,Marion Marchand,Olaf Morgenstern,David Plummer,Robert W. Portmann,Karen H. Rosenlof,Alexei Rozanov,Viktoria F. Sofieva,Johannes Staehelin,Timofei Sukhodolov,Kleareti Tourpali,Ronald J. Van der A,H. J. Ray Wang,Krzysztof Wargan,Shingo Watanabe,Mark Weber,Jeannette D. Wild,Yousuke Yamashita,Jerry Ziemke","doi":"10.5194/acp-26-13817-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13817-2026","url":null,"abstract":"A variety of chemical and dynamical processes in the troposphere and stratosphere affect tropical total column ozone (TCO), the net effect of which may cause changes in surface UV radiation and impact human and ecosystem health. We use dynamical linear modeling to estimate changes in tropical TCO and partial column ozone (PCO) in the troposphere and three stratospheric layers to assess agreement between satellite composites and chemistry-climate model simulations from two multi-model experiments (CCMI-1 and CCMI-2022). While both model experiments show tropical TCO increases over 2000–2021, multimodel-mean CCMI-2022 changes (+2.5 DU) agree slightly better with observations (+3.3 DU) than CCMI-1 (+1.6 DU). However, this overall agreement obscures multiple systematic differences in PCO changes between the models and observations across atmospheric layers. For example, since 2000 tropical tropospheric PCO increased significantly in CCMI-2022 (+1.5 DU) but not in CCMI-1 (+0.3 DU), largely explaining the difference in TCO changes. Also, despite nearly identical stratospheric PCO changes, CCMI-2022 changes are slightly more negative than CCMI-1 in the lower stratosphere (by ∼ 0.5 DU) and more positive in the middle/upper stratosphere. Crucially, substantial differences exist between observational PCO changes, particularly in the troposphere and middle/upper stratosphere, and these disagreements limit the ability to evaluate CCM fidelity for past changes. While early and late century trends are correlated across models, suggesting a potential emergent constraint on ozone, the spread in observational trends means they are unable to provide guidance on the credibility of model projections for a given emissions scenario.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"20 1","pages":"13817-13843"},"PeriodicalIF":6.3,"publicationDate":"2026-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149088026","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":"Assessing ozone dynamics during the 2023 summer STAQS field campaign using synergistic observations and model simulations","authors":"Claudia M. Bernier,Matthew S. Johnson,John Sullivan,Guillaume Gronoff,Daniel Phoenix,Fred Moshary,Raul Alvarez,Brandi McCarty,Andrew Langford,Christoph Senff,Sunil Baidar,Laura Judd","doi":"10.5194/acp-26-13795-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13795-2026","url":null,"abstract":"NASA's Tropospheric Emissions: Monitoring of Pollution (TEMPO) geostationary satellite sensor provides high temporal and spatial resolution measurements critical for monitoring air quality. During the Synergistic TEMPO Air Quality Science (STAQS) component of the 2023 AGES+ campaign, extensive surface, airborne, and remote-sensing observations were collected over the New York City/Long Island Sound region, enabling comprehensive investigation of ozone and its precursors, including nitrogen dioxide (NO 2 ) and formaldehyde (HCHO). Evaluating TEMPO (version 3) NO 2 and HCHO column retrievals against Pandora and GEO-CAPE Airborne Simulator (GCAS) observations, based on the limited number of coincident flight days available, shows TEMPO can capture urban-suburban pollution gradients and exhibits biases comparable to previous satellite validation studies with strong NO 2 column correlations ( R ≈0.79–0.81), though sharp transitions between high and low emission regions remain challenging. The high-resolution (1.33 km × 1.33 km) WRF-Chem simulation reproduces the major spatiotemporal patterns of surface ozone and NO 2 ( R ≈0.56–0.73), supporting its use to fill observational gaps. Integrating TEMPO, WRF-Chem, in situ measurements, and ozone and wind lidar observations, we characterize the spatiotemporal ozone dynamics under different pollution regimes. High-pollution days involve early urban precursor accumulation and sea-breeze-driven coastal recirculation of pollutant-rich air. Moderate days exhibit localized enhancements driven by transport, such as downwind plume transport, while low-pollution days show efficient dispersion and limited ozone formation. This multi-platform framework highlights the importance of resolving fine-scale variability in coastal and transition zones and illustrates TEMPO's potential for improving ozone forecasting and mitigation in complex environments.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"76 1","pages":"13795-13816"},"PeriodicalIF":6.3,"publicationDate":"2026-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149088084","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 impact of orography on the troposphere-to-stratosphere transport during a typhoon event in the tropics","authors":"Massimo Martina,Anahí Villalba-Pradas,Šimon Bartoň,Petr Šácha","doi":"10.5194/acp-26-13845-2026","DOIUrl":"https://doi.org/10.5194/acp-26-13845-2026","url":null,"abstract":"Stratosphere-troposphere exchange (STE) plays a fundamental role in the global atmospheric budget of chemical constituents. The troposphere-to-stratosphere transport (TST), as a part of STE, can inject anthropogenic pollutants from the Earth’s surface into the stratosphere, changing its chemical composition and influencing radiative processes. On record, TST is a multi-scale process with various contributing mechanisms, often not fully qualified nor quantified. In the tropics, typhoons and the corresponding overshooting convection and updrafts have recently been highlighted as one of the TST mechanisms, contributing for instance to the moistening of the lower stratosphere. Expanding on this, our study proposes a novel mechanism for TST connected with the interaction of typhoons with orography, including modulation of typhoon updrafts and convection, orographic lifting, and orographic gravity waves. Combining a Lagrangian modeling tool with a high-resolution simulation of the landfall of typhoon Molave (2020) in the Philippines, our results show that the presence of orography enhances the transport of air from the planetary boundary layer to the upper troposphere–lower stratosphere (UTLS) region. The presented findings advance our understanding of tropical cyclones impacts on STE and may have significant implications for the long-range atmospheric transport of pollutants originating from tropics.","PeriodicalId":8611,"journal":{"name":"Atmospheric Chemistry and Physics","volume":"24 1","pages":"13845-13860"},"PeriodicalIF":6.3,"publicationDate":"2026-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149088028","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}