Atmospheric Research最新文献

{"title":"Changing dynamics of pre-monsoon rainfall over India (1963–2022): The role ocean-atmosphere drivers and regional impacts","authors":"G.Ch. Satyanarayana ,&nbsp;Hirali Sahukar ,&nbsp;Rupraj Biswasharma ,&nbsp;N. Umakanth ,&nbsp;Sambasivarao Velivelli ,&nbsp;D. Srinivas","doi":"10.1016/j.atmosres.2026.108821","DOIUrl":"10.1016/j.atmosres.2026.108821","url":null,"abstract":"<div><div>Pre-monsoon rainfall (PMR) over India, occurring during March–May, plays a crucial role in mitigating heat stress, replenishing soil moisture, supporting agricultural planning, and sustaining water resources prior to the onset of the Indian Summer Monsoon. This study investigates the spatiotemporal variability and evolving dynamics of PMR over India during 1963–2022 by comparing two multi-decadal periods: the Past Decades (PD: 1963–1992) and the Recent Decades (RD: 1993–2022). The analysis integrates high-resolution rainfall observations from the India Meteorological Department with ERA5 reanalysis datasets, including sea surface temperature (SST), relative humidity (RH), soil moisture, total precipitable water (TPW), surface solar radiation, and wind fields at 850 hPa and 200 hPa. The results reveal a marked intensification of PMR during RD, with significant increases in both rainfall amount and the frequency of rainy days (&gt;2.5 mm day⁻¹) over southern, central, and western India, while northern and northeastern regions exhibit notable declines. This spatial reorganization of rainfall is closely linked to basin-wide Indian Ocean warming, particularly over the Arabian Sea and Bay of Bengal, which has enhanced atmospheric moisture availability and convective potential. Increased TPW, elevated near-surface RH, and higher moist static energy indicate strengthened thermodynamic instability, supported by circulation changes marked by weakened low-level anticyclonic flow over the Arabian Sea and enhanced upper-level divergence over peninsular and central India. These conditions collectively favour deep convection and vertical moisture transport during the pre-monsoon season. Multi-model simulations from six CMIP6 climate models independently reproduce the observed RD–PD rainfall increase, reinforcing confidence in the observational findings. Overall, the results suggest that the combined influence of large-scale oceanic warming and locally enhanced convective instability has created a more favourable environment for pre-monsoon convection over India in recent decades. Improving the representation of these coupled land–ocean–atmosphere feedbacks in seasonal forecasting systems is therefore essential for advancing climate adaptation strategies in agriculture, disaster preparedness, and water resource management under a rapidly warming climate.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108821"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146095929","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":"Dense gauge observations-based evaluation of gridded precipitation in southwest China and its implication for future data development","authors":"Zhuqing Zhang ,&nbsp;Long Zhao ,&nbsp;Yaozhi Jiang ,&nbsp;Jianhong Zhou ,&nbsp;Wenping Yu ,&nbsp;Qi Luo ,&nbsp;Heng Zhou","doi":"10.1016/j.atmosres.2026.108816","DOIUrl":"10.1016/j.atmosres.2026.108816","url":null,"abstract":"<div><div>Southwest China, characterized by complex topography and pronounced land surface heterogeneity, demands high-quality precipitation data for land surface processes monitoring and modeling. However, the quality of existing gridded precipitation products in this region remains unclear. Using high-density meteorological station observations from 525 national stations and 13,713 regional stations covering 2016–2020, this study comprehensively evaluates eight mainstream gridded precipitation products, including three satellite-based (GSMaP-Gauge, IMERG-Final, GSMaP-Mvk), two model-based (ERA5, ERA5-Land), and three merged (MSWEP, CMFD, GLDAS) products. Results suggest that: (1) none of the products possess satisfactory performance (KGE &lt; 0) over the entire region, and the uncertainty in precipitation estimation—reflected by inter-product discrepancies—increases significantly (from ∼150 mm/y to ∼400 mm/y) with terrain complexity (from ∼25 m to ∼1000 m of sub-grid heterogeneity); (2) all products can reasonably capture seasonal variability but fail to characterize extremely heavy and light rainfall events, and model-based products exhibit relatively better precipitation detection capability (e.g., with POD &gt;0.90 and CSI &gt; 0.50 for ERA5 and ERA5-Land); (3) while most products exhibit relatively favorable consistency with observations from national stations, their performance is remarkably degraded over regional stations (e.g., monthly KGE values decrease from &gt;0.50 to &lt;0 for all products). Additional analyses reveal that model-based products (e.g., ERA5 and ERA5-Land) can better depict the spatial distribution of precipitation in complex and sparsely monitored regions, and the incorporation of gauge observations can further mitigate abovementioned uncertainties (e.g., with Bias &lt;60 mm/y and RMSE &lt;345 mm/y for GSMaP-Gauge and MSWEP).</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108816"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089735","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":"Synergistic effects of IOD and ENSO on autumn near-surface wind speed variability across the Asian monsoon regions","authors":"Wentian Qiu ,&nbsp;Kaiqiang Deng ,&nbsp;Lianlian Xu ,&nbsp;Xi Chen ,&nbsp;Jiayi Nie","doi":"10.1016/j.atmosres.2026.108800","DOIUrl":"10.1016/j.atmosres.2026.108800","url":null,"abstract":"<div><div>The Indian Ocean Dipole (IOD) and El Niño–Southern Oscillation (ENSO) are important sources of interannual predictability in the tropical oceans. While the IOD and ENSO can exert significant impacts on global temperature and precipitation, their influence on near-surface wind speed (NSWS) in the Asian monsoon region remains unclear. This study explores how IOD and ENSO synergistically affect the NSWS variability over South and East Asia in autumn, a season characterized by peak IOD intensity and rapidly developing ENSO. The results indicate that IOD predominantly influences the NSWS variations in the tropical Indian Ocean and northern China, while ENSO has a stronger effect over southern China. Concurrent positive IOD and El Niño events generate high-pressure anomalies over the Bay of Bengal and the western Pacific, which induce easterly anomalies over the equatorial Indian Ocean and southwesterly anomalies over southern China, leading to significant NSWS reductions in both areas. In contrast, negative IOD and La Niña events produce low-pressure anomalies over the tropical oceans, resulting in an enhanced NSWS over the equatorial Indian Ocean and southern China. Furthermore, positive IOD events are suggested to weaken the NSWS in northern China by triggering northeastward-propagating Rossby waves, which induce barotropic anticyclonic circulation anomalies over northeastern China and southeasterly wind anomalies over northern China, causing declined NSWS in this area. These findings advance our understanding of the interannual variability in the NSWS across Asian monsoon region, providing valuable insights for interannual predictions of the regional wind climate and the renewable wind energy.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108800"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146033637","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":"Observational analysis of absorbing and non-absorbing aerosol effects on heavy rainfall in southwestern Iran","authors":"Zakiyeh Alibeygi,&nbsp;Maryam Gharaylou,&nbsp;Abbasali AliAkbari Bidokhti","doi":"10.1016/j.atmosres.2026.108796","DOIUrl":"10.1016/j.atmosres.2026.108796","url":null,"abstract":"<div><div>Understanding the impact of aerosols on heavy precipitation is crucial for improving predictions and management of atmospheric processes. Heavy convective precipitation often occurs within a few hours, making the investigation of aerosol influences on daily precipitation variability particularly important. In this study, heavy rainfall events in southwestern Iran were identified using ERA5 data alongside aerosol measurements from two satellite sources and the EAC4 reanalysis dataset. These datasets enabled analysis of aerosol optical depth (AOD), differentiation of aerosol types, and assessment of additional aerosol-related indices in the region. Two indices were used to classify clean and polluted conditions at macro- and micro-scales: AOD as a large-scale indicator, and cloud droplet number concentration (CDNC) as a small-scale indicator. The 25th and 75th percentiles of these indices over all rainy days were used as thresholds for clean and polluted conditions. Four aerosol types common in southwestern Iran were examined: black carbon (BC) and dust as radiatively absorbing aerosols, and sulfate and sea salt as non-absorbing aerosols. Analysis revealed three key features of daily heavy precipitation variability associated with aerosol types. Under polluted conditions defined by AOD, precipitation onset and peak occurred earlier, but event duration was shorter. In contrast, under polluted conditions defined by CDNC, precipitation started earlier but peaked later, with a longer duration. Furthermore, absorbing aerosols were associated with earlier onset and delayed peaks, whereas non-absorbing aerosols corresponded to delayed onset and extended precipitation duration. These findings highlight the distinct roles of aerosol types in modulating heavy rainfall characteristics.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108796"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146048452","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":"A Bayesian model for blending satellite precipitation estimates to enhance drought monitoring in poorly gauged regions","authors":"Vinícius de Matos Brandão Raposo,&nbsp;André Ferreira Rodrigues,&nbsp;Veber Afonso Figueiredo Costa","doi":"10.1016/j.atmosres.2026.108799","DOIUrl":"10.1016/j.atmosres.2026.108799","url":null,"abstract":"<div><div>Droughts are among society's most damaging climatic disasters, representing a complex phenomenon in which precipitation plays a central role. In poorly gauged regions, precipitation estimates from remote sensing have been widely employed. However, these data often exhibit bias and may not accurately depict the spatiotemporal variability of the rainfall processes. To address these problems, this study aims to propose a novel prediction model to enhance the reliability of rainfall estimates in poorly gauged regions by utilizing a Bayesian approach to blend multiple Satellite Precipitation Estimates (SPEs). CHIRPSv2, IMERG V06, and CMORPH were the selected SPEs for building the blending model, which was applied to estimate monthly rainfall data in the Doce River catchment and the mid-lower portion of the São Francisco River catchment, both in Brazil. Comparative analyses between rainfall gauging data and the SPEs, as well as the blending model, unveiled the enhanced performance of the new precipitation estimates, demonstrating consistently lower values for RMSE, NRMSE, and PBIAS in both study areas. We also assessed the ability of the SPEs and the blending model to capture drought conditions across different aggregation scales of the Standardized Precipitation Index (1, 3, 6, 9, and 12 months). Regarding the number of drought months and magnitudes accurately identified, the blending model consistently achieved better performance from SPI-1 to SPI-9, but was outperformed at SPI-12 by different SPEs. Overall, despite its increased complexity, this approach can be effective for drought characterization in regions with sparse monitoring and further hydrological applications on a monthly scale.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108799"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146033635","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":"WAWL-net: A hybrid model combining weighted aggregation and wavelet convolutions for tropical cyclone intensity estimation","authors":"Yuchao Ni ,&nbsp;Yuanping Zhu ,&nbsp;Baihua Xiao ,&nbsp;Qing Liu","doi":"10.1016/j.atmosres.2026.108797","DOIUrl":"10.1016/j.atmosres.2026.108797","url":null,"abstract":"<div><div>Accurate tropical cyclone (TC) intensity estimation can improve the effectiveness of numerical forecasts of TC intensity. The similarity between the TC categories and the significant differences within each category make this task highly challenging. In TC intensity estimation, the most discriminative features are in the center region of the TC. The limitations of existing methods are from their failure to effectively capture both local and global feature simultaneously. In this paper, a hybrid network is proposed in which Weight Aggregated Convolution adaptively adjusts kernel weights to capture local features, while linear attention is used to model global dependencies. In addition, a wavelet transform convolution layer is added to improve frequency domain sensitivity for more efficient feature extraction and comprehensive data understanding. The proposed WAWL-Net model effectively integrates local structural details and global contextual dependencies for TC intensity estimation, significantly improving the model's ability to accurately estimate the TC intensity with lower computational complexity. The effectiveness of our network was validated using multi-channel (IR, WV, PMW) channel data on the TCIR benchmark, where it achieved state-of-the-art performance.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108797"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146072706","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":"Data assimilation of aerosol optical depth (AOD) in CMA-MESO/CUACE model to improve weather predictions in China","authors":"Jia Hong ,&nbsp;Wenyuan Chang ,&nbsp;Wei Han ,&nbsp;Zhaorong Zhuang ,&nbsp;Hao Wang ,&nbsp;Lei Bi ,&nbsp;Xueshun Shen","doi":"10.1016/j.atmosres.2026.108780","DOIUrl":"10.1016/j.atmosres.2026.108780","url":null,"abstract":"<div><div>Aerosols play key role in cloud nucleation and atmospheric radiation processes, thus an accurate aerosol modeling is critical for numerical weather predictions. This study establishes an aerosol optical depth (AOD) 3D-Var data assimilation (DA) scheme for the CMA-MESO/CUACE weather prediction model, assimilates AOD retrievals derived from the Fengyun-4B (FY-4B) satellite, and evaluates the impacts of AOD DA on weather predictions through a month-long hindcast experiment. The AOD observation operator is built based on a look-up table, of which the aerosol optical properties (AOP) are computed for non-spherical dust with the invariant imbedding T-matrix method and for spherical anthropogenic aerosols with the Lorenz–Mie method, respectively. The month-long model results are evaluated using the AERONET measurements and ground-based weather observations across China. Results show a significant reduction of the bias of the AOD prediction by up to 0.2 by assimilating AOD retrievals. The improved AOD predictions further positively influence the modeling of the atmospheric thermal-dynamic structures. The Mean Absolute Error (MAE) of regional 2-m air temperature and 10-m wind speed predictions can be reduced by up to 0.7 K and 0.2 m s⁻¹, respectively. The benefits of AOD DA demonstrate the effectiveness of the developed AOD assimilation scheme and the necessity of incorporating satellite AOD data for improving weather predictions.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108780"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146001129","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":"Synoptic flow patterns and key factors controlling rapid intensification onset of tropical cyclones along the China coast","authors":"Xiaomeng Li ,&nbsp;Ruifen Zhan ,&nbsp;Yuqing Wang ,&nbsp;Fengxia Yan","doi":"10.1016/j.atmosres.2026.108795","DOIUrl":"10.1016/j.atmosres.2026.108795","url":null,"abstract":"<div><div>Rapid intensification (RI) of tropical cyclones (TCs) near the China coast poses heightened risk because short lead times limit preparedness. Using ERA-Interim reanalysis, Tropical Rainfall Measuring Mission precipitation, and TC best-track data, we apply an obliquely rotated T-mode principal component analysis to classify synoptic environments for RI events and diagnose controlling factors with composites and a Box Difference Index. Four synoptic flow patterns emerge: (1) MSS: combined monsoon trough, subtropical high, and South Asian high; (2) MS: monsoon trough interacting with the subtropical high; (3) SH: subtropical-high-dominated; and (4) MW: monsoon trough with a southward-penetrating midlatitude westerly trough. Across regimes, RI is preceded by radius-of-maximum-wind contraction, increased TC fullness, and more axisymmetric inner-core precipitation. Further analyses show that MSS/MS feature reduced vertical wind shear and stronger low-level vorticity with enhanced precipitation; SH shows the weakest shear and strongest upper-level divergence as the ridge extends westward; MW favors already compact, intense storms that can withstand shear asymmetry tied to the midlatitude westerly trough. These results clarify how large-scale flow modulates RI onset near the China coast and suggest that combining synoptic-pattern recognition with environmental predictors can improve RI guidance for coastal warnings.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108795"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026061","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":"South Pacific Convergence Zone driven atmospheric river changes over Dronning Maud Land, Antarctica: Observational and CESM2 LENS2 evidence","authors":"Qingli Wu,&nbsp;Yetang Wang,&nbsp;Zhaosheng Zhai,&nbsp;Min Zhou","doi":"10.1016/j.atmosres.2026.108794","DOIUrl":"10.1016/j.atmosres.2026.108794","url":null,"abstract":"<div><div>Atmospheric river (AR) landfalls profoundly impact Antarctic snowfall accumulation, surface melting and ice shelf calving/collapse. However, comprehensive case studies are still required to better understand AR changes and their underlying mechanisms. Here, we use ERA5 reanalysis and Community Earth System Model version 2 (CESM2) ensembles to examine the spatial distribution and long-term trends of Antarctic ARs during 1979–2022, and also investigate the mechanisms behind it by distinguishing between dynamic and thermodynamic effects. Reanalysis shows a strong increase in annual AR frequency over Dronning Maud Land (DML) in Antarctica during 1979–2022, predominantly driven by dynamical processes. Sea surface temperature (SST) anomalies in the South Pacific Convergence Zone (SPCZ) strongly modulate AR intensification over DML by enhancing convection and exciting a Rossby wave train, which deepens the Weddell Sea cyclone anomaly and amplifies downstream high-pressure ridges. Fingerprinting experiments with the 50-member CESM2 ensemble confirm the pivotal role of internal Pacific variability in reproducing observed AR trends. These results highlight the importance of accurately representing SPCZ SST variability for understanding the mechanisms driving Antarctic AR changes.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108794"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146048455","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":"Impact of tropospheric ozone-radiation interactions on summer ozone air quality over eastern China during 2010–2019","authors":"Yuqi Guan ,&nbsp;Jia Zhu ,&nbsp;Xueqing Wang ,&nbsp;Lei Chen ,&nbsp;Xipeng Jin ,&nbsp;Xu Yue ,&nbsp;Hong Liao","doi":"10.1016/j.atmosres.2026.108817","DOIUrl":"10.1016/j.atmosres.2026.108817","url":null,"abstract":"<div><div>As an air pollutant and atmospheric oxidant, tropospheric ozone (O₃) is also recognized as a significant greenhouse gas and a key radiatively active species in the atmosphere. In this study, we examine the impact of tropospheric ozone–radiation interactions, explicitly quantifying the effects of meteorological feedback (TrO₃-Met) and photolysis feedback (TrO₃-Phot) on near-surface O₃ concentrations over eastern China in June by using the WRF-Chem model embedded with improved process analysis scheme. A ten-year averaged simulation from 2010 to 2019 is conducted to improve the representativeness of quantified contributions of TrO₃-Met and TrO₃-Phot. Results show that TrO₃-Met increases O₃ concentrations by an average of +0.1 μg·m⁻³ over eastern China, with more pronounced effects over the North China Plain (NCP, +0.4 μg·m⁻³), the Yangtze River Delta (YRD, +0.5 μg·m⁻³), and the Pearl River Delta (PRD +0.1 μg·m⁻³), and the enhanced vertical mixing from aloft to the lower level is the dominant process contributing to the elevated O₃ levels. TrO₃-Phot reduces daytime ozone photolysis rate (<em>J</em>[O¹D]) by 34.5% and OH radical concentrations by 21.0%, resulting in 1.0% reduction (−1.0 μg·m⁻³) in surface O₃ over eastern China, with more substantial reductions over the NCP (−7.8%), YRD (−6.4%), and PRD (−4.2%). The intensified chemical removal process is primarily responsible for the overall decline. Further analysis of O₃-related gas-phase chemical reactions based on integrated reaction rate reveals that weakened HOx-driven oxidation increases the participation of tropospheric O₃ in alternative oxidation pathways, resulting in a negative net O₃ production rate, thereby explaining the reduction in surface O₃ concentrations.</div></div>","PeriodicalId":8600,"journal":{"name":"Atmospheric Research","volume":"335 ","pages":"Article 108817"},"PeriodicalIF":4.4,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089729","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}