Atmospheric Research最新文献

{"title":"Influence of the QBO vertical structure on the interannual variability of the Hadley circulation in autumn","authors":"Ying Wang ,&nbsp;Jiali Luo ,&nbsp;Juan Feng ,&nbsp;Yan Xia ,&nbsp;Fuhai Luo ,&nbsp;Fei Xie","doi":"10.1016/j.atmosres.2026.108792","DOIUrl":"10.1016/j.atmosres.2026.108792","url":null,"abstract":"<div><div>The Hadley circulation (HC) is the dominant meridional circulation in the tropics, and its interannual variability exerts a strong influence on the global climate system. While the El Niño-Southern Oscillation (ENSO) is a well-known tropospheric driver, the stratospheric Quasi-Biennial Oscillation (QBO) also contributes to tropical variability. However, the mechanisms through which the QBO modulates HC variability remain unclear. Using reanalysis data and CMIP6 model outputs, this study demonstrates that the vertical structure of the QBO plays a crucial role in modulating the interannual variability of the HC during autumn, particularly over the western Pacific. When the QBO vertical structure index (QBOVI) is greater than 0, a secondary circulation forms, characterized by equatorial ascent and midlatitude descent. This circulation is associated with a cold anomaly in the lower stratosphere, which reduces static stability near the tropopause and strengthens the local HC over the western Pacific. Conversely, when the QBOVI is less than 0, the static stability in the upper troposphere is enhanced, leading to a weakening of the HC. The evaluation of six selected high-top CMIP6 models shows that the models fail to capture the observed relationship between the QBO vertical structure and the HC. This limitation may arise from biases in simulating the link between HC intensity and static stability, as well as from difficulties in reproducing the QBO's regulation of the thermal structure near the tropopause. Improving model representations of this modulation could enhance the simulation and prediction of interannual HC variability.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"334 ","pages":"Article 108792"},"PeriodicalIF":4.4,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of tropical cyclone ‘Biparjoy’ in exacerbating heatwaves and aerosol forcing over the Indian subcontinent","authors":"Shravani Banerjee ,&nbsp;B. Padmakumari ,&nbsp;M. Rajeevan","doi":"10.1016/j.atmosres.2026.108790","DOIUrl":"10.1016/j.atmosres.2026.108790","url":null,"abstract":"<div><div>Tropical cyclones (TCs) are typically associated with intense convection and heavy rainfall; however, their broader influence on concurrent heatwave (HW) and air-quality extremes remains poorly understood. This study examines the complex interactions between cyclone dynamics, HWs, and aerosols during the prolonged TC Biparjoy in June 2023. While the cyclone produced widespread rainfall over western and northwestern India, persistent HWs prevailed across the central-east and peninsular regions. The cyclone's slow movement over northwestern India reinforced subsidence and high-pressure anomalies, leading to a 2–4 °C rise in surface temperatures and an expansion of the extent and intensity of HWs. Satellite observations revealed elevated aerosol loading up to 5 km over the HW-affected regions, dominated by absorbing dust and polluted dust aerosols. Analysis of dust transport and circulation patterns showed that strong westerly winds trailing the cyclone entrained coarse dust aerosols (&gt;1.0 μm) from the Middle East and Central Asia, contributing to the widespread vertical enhancement of aerosols across central and peninsular India. Aerosol Direct Radiative Forcing (ADRF) analysis showed positive atmospheric forcing and negative surface forcing, implying a radiative imbalance that may have intensified near-surface heating through feedback mechanisms. The results highlight a compound TC-HW-Aerosol event, wherein cyclone-induced subsidence and dust transport jointly amplified regional heat extremes and atmospheric warming despite concurrent rainfall elsewhere.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"334 ","pages":"Article 108790"},"PeriodicalIF":4.4,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observations of a dryline interacting with a back-building mesoscale convective system in the Kalahari region of southern Africa","authors":"Lynette van Schalkwyk ,&nbsp;Ross C. Blamey ,&nbsp;Callum Munday ,&nbsp;Richard Washington ,&nbsp;Chris J.C. Reason","doi":"10.1016/j.atmosres.2025.108694","DOIUrl":"10.1016/j.atmosres.2025.108694","url":null,"abstract":"<div><div>A unique set of observations allows the analysis of the environment in which a back-building mesoscale convective system (MCS) developed along a dryline in the semi-arid southern Kalahari region of southern Africa during 28 and 29 December 2023. This MCS resulted in widespread rainfall, roughly equivalent to the December–February average, causing localized flooding and power failures. MCS development occurred along a dryline in a highly unstable, but weakly sheared environment. Near surface moisture gradients exceeded 6 g kg⁻¹ 100 km⁻¹ in places on the dryline during morning and evening of 28 December but were weaker that afternoon. CAPE values exceeded 1000 J.kg⁻¹ shortly after sunrise within the first 100 km of the moist side of the dryline and MU-CAPE exceeded 3000 J kg⁻¹ at 08:00 and 12:00 UTC. Convection started adjacent to the dryline and once individual storm cells merged to form a MCS, new cells continued to develop along the dryline before being steered downstream by mid-level northwesterly winds. Back-building and a strong northeasterly low-level inflow contributed to renewed development along the storm's axis during the night-time, extending its lifespan to at least 13 h. These findings provide new insights into the contribution of MCSs to seasonal rainfall for the southern Kalahari region and a valuable example of mesoscale interactions between a dryline and individual storm cells at night.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"333 ","pages":"Article 108694"},"PeriodicalIF":4.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing wind forecasts through assimilation of maximum wind observations in WRF-3DVar: A comparison with conventional AWS data for a severe squall line","authors":"Dongmei Xu ,&nbsp;Ruonan Zhao ,&nbsp;Wei Sun ,&nbsp;Jinzhong Min ,&nbsp;Zhixin He ,&nbsp;Feifei Shen","doi":"10.1016/j.atmosres.2025.108733","DOIUrl":"10.1016/j.atmosres.2025.108733","url":null,"abstract":"<div><div>Convective-scale wind analysis and short-range forecast remains challenging due to the limited availability of high-temporal-resolution surface wind observations. This study investigates the impact of assimilating conventional 10-min average wind (CAW) and maximum 2-min average wind (MAW) observations from automatic weather stations on convective-scale wind analysis and short-term forecasting, focusing on a severe squall line event that affected Beijing on 30 May 2024. A series of sensitivity experiments were conducted using the WRF-3DVar system, including both single observation tests and full-domain assimilation experiments. Results indicate that CAW data, owing to their high temporal frequency, contribute to localized improvements in near-surface wind analysis and enhance the depiction of cold pool intensity. In contrast, MAW data exert broader, more profound influence that extends through multiple vertical layers, enabling a markedly more accurate reconstruction of three-dimensional wind and the full spatial footprint of the cold pool in the convective system. The comparative analysis demonstrates that MAW assimilation generates larger wind increments, broader spatial coverage, and better agreement with mesoscale observations than CAW assimilation. Additionally, MAW data yield a more realistic temporal evolution of surface winds and more coherent representation of gust front dynamics. These findings underscore the superior capability of MAW observations in convective-scale wind assimilation. Their expansive spatial reach and robust dynamical coherence offer greater potential for improving short-term convective forecasts, positioning them as an indispensable resource for the next generation of nowcasting and data-assimilation frameworks.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"333 ","pages":"Article 108733"},"PeriodicalIF":4.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145845314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spring extreme heat in the Indochina Peninsula enhances the prediction skill of summer precipitation in Central China","authors":"Yihua He ,&nbsp;Wei Lou ,&nbsp;Cheng Sun ,&nbsp;Menghao Dong ,&nbsp;Zichen Song ,&nbsp;Linfeng Shi ,&nbsp;Yibing Tong","doi":"10.1016/j.atmosres.2025.108710","DOIUrl":"10.1016/j.atmosres.2025.108710","url":null,"abstract":"<div><div>Summer precipitation in Central China (CC) is typically influenced by ocean-atmosphere coupling processes. However, the mechanisms through which land surface processes in surrounding regions affect CC precipitation, particularly those over the Indochina Peninsula (ICP), remain poorly understood. We propose that extreme heat events (TX90P) over the ICP during March–April-May (MAM) enhance June–July-August (JJA) precipitation in CC. ICP MAM TX90P establishes a self-reinforcing feedback loop through energy and moisture exchange processes at the land-atmosphere (L-A) interface, thereby amplifying the intensity of extreme heat events. Extreme heat events are accompanied by high-pressure systems with anomalous subsidence of airflow that suppress precipitation and reduce soil moisture (SM). The resulting dry soil establishes a positive feedback mechanism with precipitation, enabling the anomalous SM reduction to persist into JJA. This soil moisture memory effect-induced drought leads to weakened vertical motion over the ICP, promoting the formation of an anticyclonic circulation pattern spanning the ICP and Western Pacific (WP), which subsequently strengthens southwesterly winds that transport moisture toward CC, resulting in enhanced precipitation. Simulations using a Linear Baroclinic Model (LBM) confirm that ICP extreme heat events generate southwesterly wind anomalies, facilitating northeastward moisture transport to CC. A multiple linear regression model incorporating MAM TX90P, preceding winter El Niño-Southern Oscillation (ENSO), and preceding winter Indian Ocean Dipole (IOD) effectively reproduces observed JJA CC precipitation (<em>r</em> = 0.62). This result demonstrates that incorporating extreme heat-related land surface processes significantly improves precipitation prediction skill compared to models relying solely on oceanic variability.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"333 ","pages":"Article 108710"},"PeriodicalIF":4.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145785337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 climatology of complexity: Spatiotemporal analysis of summer subtropical anticyclones over Southwest Asia and adjacent regions","authors":"Morteza Keyhani,&nbsp;Abbas Mofidi,&nbsp;Azar Zarrin","doi":"10.1016/j.atmosres.2025.108713","DOIUrl":"10.1016/j.atmosres.2025.108713","url":null,"abstract":"<div><div>This study provides a comprehensive climatology of summer subtropical anticyclones (SAs) over Southwest Asia using daily ERA-Interim geopotential height data (1990–2019) across six pressure levels (900–100 hPa). Anticyclones were identified on 2760 summer days using combined objective and subjective methods, enabling a multi-level assessment of their frequency, spatial organization, preferred locations, vertical structure, seasonal evolution, and long-term variability. SAs are found throughout the atmospheric column, with maximum frequencies in the mid-troposphere and minimum occurrences near the surface. Distinct spatial modes emerge at different levels—bimodal at 500 hPa, trimodal at 700 hPa, and quadrimodal at 100–200 hPa—revealing finer spatial complexity than earlier climatologies. A key finding is a pronounced vertical seesaw pattern in seasonal occurrence: lower-tropospheric anticyclones peak in June but decline sharply in July, while mid- and upper-tropospheric anticyclones intensify. This indicates a coordinated vertical redistribution of anticyclonic activity during summer. Interlevel relationships exhibit strong coherence in the upper troposphere, whereas weaker correlations between adjacent lower and mid-tropospheric levels suggest level-dependent formation mechanisms and vertical tilt. Regionally, the study refines the characteristics of the Turkmenistan, Zagros, and Arabian anticyclones, highlighting the vertical continuity of the Arabian anticyclone and its sensitivity to surface thermal forcing. Long-term analysis reveals no significant meridional shifts but shows a notable increase in anticyclone frequency at 700 hPa, likely linked to recent warming over the Arabian Peninsula. Overall, the findings demonstrate the dynamical complexity of SAs across Southwest Asia and provide an updated framework for understanding their variability and climate relevance.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"333 ","pages":"Article 108713"},"PeriodicalIF":4.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145823517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation and analysis of CO2 concentration in China from 2009 to 2021 based on the WRF-Chem model","authors":"Wenhao Liu,&nbsp;Yong Xue,&nbsp;Xiaolu Ling,&nbsp;Botao He,&nbsp;Chenggang Li,&nbsp;Liying Han","doi":"10.1016/j.atmosres.2025.108732","DOIUrl":"10.1016/j.atmosres.2025.108732","url":null,"abstract":"<div><div>Monitoring carbon dioxide (CO₂) concentration is considered an effective approach to controlling greenhouse gas emissions. Simulating CO₂ concentration variations using atmospheric chemistry models can compensate for the spatial and temporal limitations of ground-based and satellite observations. In this study, the WRF-Chem (Weather Research and Forecasting model coupled with Chemistry) model was employed to simulate CO₂ concentrations over central and eastern China from 2019 to 2021. The reliability of the simulation results was verified through comparisons with satellite data from OCO-2 (Orbiting Carbon Observatory 2), OCO-3 (Orbiting Carbon Observatory 3), and GOSAT (Greenhouse Gases Observing Satellite). Additionally, the results were validated against observational data from TCCON (Total Carbon Column Observing Network) and WDCGG (World Data Centre for Greenhouse Gases). The RMSE of the WRF-Chem simulation results compared to TCCON and WDCGG station observations were 2.146 ppm and 2.239 ppm, respectively, with R of 0.716 and 0.825. When compared to OCO-2, OCO-3, and GOSAT satellite observations, the RMSE were 2.000 ppm, 2.080 ppm, and 1.827 ppm, respectively, with R values of 0.792, 0.831, and 0.837. Based on a comparative analysis integrating WRF-Chem simulations from 2009 to 2021, this study reveals an upward trend in XCO₂ concentrations over China, with an average annual growth rate of approximately 2.0 to 2.5 ppm. Although the growth rate slowed during 2019 to 2020, likely influenced by the COVID-19 pandemic, concentrations continued to increase annually. This result indicates that short-term variations in anthropogenic emissions can moderate the rate of increase but do not alter the long-term trend. The consistency between simulated CO₂ concentrations, MEIC inventory emission trends, and ground-based observations further validates the simulation accuracy and suggests the reliability of MEIC in characterizing China's carbon emission changes during the pandemic.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"333 ","pages":"Article 108732"},"PeriodicalIF":4.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145845316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal variability and sources of brown carbon in Wuhan: Insights from Bayesian modeling and organic tracers-based source apportionment","authors":"Zongjun Li ,&nbsp;Qiongqiong Wang ,&nbsp;Yongyi Zhao ,&nbsp;Zhongliang Huang ,&nbsp;Kezheng Liao ,&nbsp;Huan Yu ,&nbsp;Shaofei Kong ,&nbsp;Nan Chen ,&nbsp;Bo Zhu ,&nbsp;Xiao He ,&nbsp;Mingjie Xie ,&nbsp;Jian Zhen Yu","doi":"10.1016/j.atmosres.2025.108736","DOIUrl":"10.1016/j.atmosres.2025.108736","url":null,"abstract":"<div><div>Brown carbon (BrC) is an important constituent of atmospheric carbonaceous aerosols, and accurately measuring its mass concentration and optical property is of great importance to reduce its uncertainties in model parametrization. This study deployed the novel Bayesian inference (BI) model to determine the BrC mass concentration and absorption on an hour-by-hour basis, using online measurements of multi-wavelength light absorption and total carbon (TC) data over June and December 2023 in Wuhan, central China. BrC mass contributed to 42 % of the TC aerosol and showed comparable level in two months, while its absorption showed distinct seasonal contrast with much higher values in December. Important BrC compositions including various organic tracers were measured, taking advantage of the concurrently collected daily 12-h offline filter samples. BrC mass and absorption showed good correlations with important components such as oxygenated-polycyclic aromatic hydrocarbons (PAHs), light PAHs and biomass burning tracer-saccharides. Organic-tracer based source apportionment was conducted for both BrC mass and absorption, and nine distinct source factors were resolved. Secondary sources especially secondary organic aerosol (SOA) factor dominated BrC mass contributions in June, while biomass burning emerged as the primary source in December. The primary sources contributing to BrC absorption were SOA and biomass burning in June, while biomass burning dominated in December. Coal combustion, which was a minor source to BrC mass, was a non-negligible contributor to BrC absorption in both months. Different control measures should be implemented to effectively control BrC mass for improved air quality and to mitigate BrC absorption for its climate effect. The results from this study broaden our understandings of the relationship among chemical, optical and sources of BrC, offering significant implications for environmental management.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"333 ","pages":"Article 108736"},"PeriodicalIF":4.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145895035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revealing ozone persistence under typhoon subsidence in the Greater Bay Area using lidar observations","authors":"Rui He ,&nbsp;Zhongcai Wang ,&nbsp;Yongfan Wu ,&nbsp;Yan You ,&nbsp;Yan Xiang ,&nbsp;Andi Zhang ,&nbsp;Chenglei Pei ,&nbsp;Tianshu Zhang","doi":"10.1016/j.atmosres.2026.108737","DOIUrl":"10.1016/j.atmosres.2026.108737","url":null,"abstract":"<div><div>Ozone (O₃) pollution poses a critical air quality challenge in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA), particularly under typhoon peripheral circulation. However, the vertical processes governing O₃ persistence remain poorly understood. This study investigates a persistent O₃ pollution episode in July 2023 using the WRF-Chem model, data assimilation, and the GBA O₃ Lidar Network. Results reveal pronounced city-specific differences in O₃ persistence mechanisms. In Macao, extended O₃ exceedance was driven by persistent typhoon-induced subsidence, suppressed boundary-layer mixing, and convergence of transported O₃-rich air masses, forming a regional O₃ pool. Conversely, Shenzhen experienced rapid O₃ dissipation due to the inflow of cleaner maritime masses. Lidar observations captured distinct O₃ stratification within boundary layer under the influence of typhoon subsidence. These findings elucidate city-specific O₃ responses under complex meteorological conditions, providing robust scientific guidance for tailored air quality strategies in coastal megacity clusters.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"333 ","pages":"Article 108737"},"PeriodicalIF":4.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145895034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of the boreal spring arctic oscillation on the midsummer maritime continent precipitation","authors":"Yining Tao ,&nbsp;Gang Zeng ,&nbsp;Chen Chen ,&nbsp;Aminu Dalhatu Datti ,&nbsp;Zhongxian Li","doi":"10.1016/j.atmosres.2025.108730","DOIUrl":"10.1016/j.atmosres.2025.108730","url":null,"abstract":"<div><div>The Arctic Oscillation (AO), the dominant mode of extratropical Northern Hemisphere circulation, is known to influence midlatitude climate variability, but its impacts on tropical rainfall–particularly over the Maritime Continent (MC)–remain unclear. Here, we examine the influence of the boreal spring AO on midsummer (July–August) MC precipitation during the period 1979–2023. The results reveal a significant negative relationship between midsummer MC precipitation and the preceding March–April AO. Further examination identifies a physical mechanism linking the two: during the negative phase of the March–April AO, atmosphere–ocean interactions generate warm sea surface temperature (SST) anomalies in the North Atlantic that persist from March to August. These mid–latitude SST anomalies in the North Atlantic trigger an atmospheric wave train that propagates from the North Atlantic to the North Pacific, ultimately inducing pronounced westerly wind anomalies in the upper troposphere and easterly wind anomalies in the lower troposphere over the tropical western Pacific in July–August. This circulation pattern enhances vertical wind shear, promoting anomalous ascent via dynamic pumping and increasing rainfall. Simulations using the Community Atmosphere Model (CAM5.3) further validate the proposed mechanism.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"333 ","pages":"Article 108730"},"PeriodicalIF":4.4,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145823513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}