Journal of Geophysical Research: Atmospheres最新文献

{"title":"Contrail Formation Within Cirrus: Contrail Induced Perturbations and Cirrus Adjustments","authors":"Pooja Verma,&nbsp;Ulrike Burkhardt","doi":"10.1029/2025JD045269","DOIUrl":"https://doi.org/10.1029/2025JD045269","url":null,"abstract":"<p>Contrail formation constitutes a large fraction of the aviation climate impact. But only part of the effect has been studied in detail, as research focused on contrail formation in cloud-free air. Even though it is known that the impact of contrail formation within cirrus can be detected in space-born remote sensing data, little research has dealt with the associated processes. Accordingly, the global climate impact of contrail cirrus is as yet unknown and the impact of contrail formation within cirrus is not yet included in aviation climate assessments. We use the high-resolution ICON-LEM, including a representation of contrail formation, to study the impact of contrail formation within cirrus clouds. We find that contrail formation leads to large peaks in ice crystal number concentration which eventually have an impact on the microphysical properties of large parts of the cirrus. As ice crystal sizes are initially very small, contrail formation reduces sedimentation and, therefore, affects the vertical distribution of cloud ice. Increases in the ice water path at the location of contrail formation lead to corresponding decreases in the larger vicinity which are most prominent at lower levels. Those decreases may be interpreted as fast cloud adjustment. Adjustments are non-local in space and time. Their strength depends on the synoptic situation and varies spatially even within a cloud deck. Our work improves the process understanding of contrail formation within clouds and the associated cloud adjustments, important steps toward including this effect in aviation climate assessments and mitigation studies, such as contrail avoidance.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JD045269","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Signal-Derived Retrieval Reduces Bias in TEMPO NO2","authors":"S. J. Beaudry,&nbsp;R. C. Cohen","doi":"10.1029/2025JD045606","DOIUrl":"https://doi.org/10.1029/2025JD045606","url":null,"abstract":"&lt;p&gt;Satellite measurements of &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;NO&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{NO}}_{2}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; are widely used for investigations of emissions, pollution exposure, and photochemical ozone production. The most commonly available data products compromise on accuracy and spatial resolution in favor of lower compute time. In addition to limited spatial resolution, inaccurate modeling of winds and misrepresentation of the &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;NO&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{NO}}_{2}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; lifetime contribute to large systematic errors in the satellite retrievals that depend on these modeled outputs. We introduce a signal-derived retrieval (SDR) for Tropospheric Emissions: Monitoring of Pollution (TEMPO) &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;NO&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{NO}}_{2}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; which derives instrument-resolution a priori &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;NO&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{NO}}_{2}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; profiles from measured slant column densities. This approach enables fast reprocessing of TEMPO data and removes the gradient smoothing caused by low resolution priors and systematic errors in models. The SDR product reduces the negative bias of TEMPO total &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mtext&gt;NO&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{NO}}_{2}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; against Pandora reference measurements by &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;mi&gt;%&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $3%$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, with a larger impact on the tropospheric column. This bias correction is shown to have important effects on the application of TEMPO &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 ","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JD045606","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Integrated Uncertainty Framework for the China-MST 3.0 Global Surface Temperature Data Set","authors":"Zichen Li,&nbsp;Qingxiang Li,&nbsp;Boyang Jiao,&nbsp;Qiya Xu,&nbsp;Sihao Wei,&nbsp;Xutong Ru,&nbsp;Peng Si,&nbsp;Liya Chao,&nbsp;Hanyu Zhang,&nbsp;Jiaxue Lin,&nbsp;Longshi Liao,&nbsp;Huixian Zhang,&nbsp;Boyin Huang,&nbsp;Phil Jones","doi":"10.1029/2025JD044732","DOIUrl":"https://doi.org/10.1029/2025JD044732","url":null,"abstract":"<p>Global Mean Surface Temperature (GMST) is among the most important indicators of climate change, and its associated uncertainties affect the assessment of historical warming and the formulation of mitigation and adaptation policies. China-MST 3.0 is a newly updated global surface temperature data set that merges China-LSAT 2.1 for Land Surface Air Temperature (LSAT) and ERSST v6 for Sea Surface Temperature (SST). In this study, we develop a systematic and traceable uncertainty analysis framework for the construction process of this data set. Specifically, we comprehensively evaluate three components of LSAT uncertainty: observation, analysis, and coverage uncertainties, while describing SST uncertainty in terms of both parametric and reconstruction uncertainties. We also provide a quantitative assessment of the spatial and temporal evolution of these uncertainties. The results show that LSAT uncertainty is generally larger than that of SST and is mainly driven by coverage uncertainty. The overall uncertainty in GMST shows a significant downward trend, with the annual 1<i>σ</i> uncertainty falling below 0.03°C in recent decades, indicating high data reliability. However, uncertainty was high during the second-half of the 19th century and remains large at high latitudes in the Southern Hemisphere. Comparative analyses indicate that China-MST 3.0 is broadly consistent with other data sets in both the magnitude and temporal evolution of GMST uncertainty. These findings demonstrate the utility of China-MST 3.0 as a valuable tool for evaluating global warming since the 1850s.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686197","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":"Sensitivity of Upper Tropospheric Ozone to Its Precursors During the Asian Summer Monsoon","authors":"Chaitri Roy,&nbsp;Anoop S. Mahajan,&nbsp;D. C. Ayantika,&nbsp;Sachin D. Ghude,&nbsp;Gaurav Govardhan","doi":"10.1029/2025JD044919","DOIUrl":"https://doi.org/10.1029/2025JD044919","url":null,"abstract":"<p>Ozone in the upper troposphere (UT) is critical for maintaining radiative balance at the top of the atmosphere (TOA). This study utilizes Aerosol and Chemistry Model Intercomparison Project (AeroChemMIP) simulations to investigate photochemical pathways influencing ozone production in the UT during the Asian summer monsoon (ASM). We analyze the impact of convectively transported ozone precursors like nitrogen oxides (NO_x), non-methane volatile organic compounds (NMVOCs), and carbon monoxide (CO) on the sensitivity of ozone formation over the Asian region in the UT. Our results show an increase of ozone in the UT by ∼70% in the present-day (2014) compared to the pre-industrial era (1850). This excess ozone (∼35 ppb) is photochemically produced due to the elevated levels of NO_x (∼152 ppt) and CO (∼21 ppb) in the UT along with its direct convective transport from the boundary layer. Changes in formaldehyde (HCHO), a proxy for VOCs, are negligible in the UT. Analysis of ozone in relation to its precursors (HCHO, CO, and NO₂) suggests that the UT is primarily NO_x-limited, and ozone production follows the NO_x-CO-O₃ pathway. The UT ozone changes due to increasing ozone precursor emissions affect the radiative balance by exerting a positive ozone radiative effect of +0.9 Wm⁻² at the TOA over the ASM anticyclone region. These findings indicate that suitable emission control strategies must be formulated to reduce NO_x and CO emissions to limit ozone enhancement in the UT.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686198","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":"Extreme Zonal Dipole Pattern of January Blocking Days Between the Eastern North Atlantic and Ural in 2008: The Combined Impact of Sea Surface Temperature and Newly Formed Arctic Sea Ice Anomalies","authors":"Yifan Xu,&nbsp;Ke Fan","doi":"10.1029/2025JD045202","DOIUrl":"https://doi.org/10.1029/2025JD045202","url":null,"abstract":"<p>A pronounced dipole anomaly of blocking days (BDD) between the eastern North Atlantic (ENA) and Ural occurred in January 2008, representing the strongest positive phase in recent decades, marked by considerably increased (decreased) Ural (ENA) blocking days. The background circulation exhibits a positive North Atlantic Oscillation phase, with diminished (strengthened) westerly winds and meridional potential vorticity gradients over Ural (ENA), which enhances (suppresses) blocking days. Under the combined anomalies of strong North Atlantic warming, robust La Niña and substantial Barents–Kara newly formed sea ice reduction, along with their joint effects inducing significant atmospheric wave responses, the notable BDD is facilitated. Over the North Atlantic, enhanced surface turbulent heat fluxes excite upward-propagating Rossby waves and increase atmospheric baroclinicity, favoring local quasi-barotropic low-pressure anomalies that modulate background flow through downstream Rossby wave energy dispersion, thereby influencing the BDD. Over the Pacific, La Niña–associated cooling suppresses convection, triggering a Gill-type response that strengthens anomalous easterly winds. In combination with reduced baroclinicity over the North Pacific, this enhances the subtropical anticyclone and initiates a downstream Rossby wave train that promotes the BDD. Moreover, declined Barents–Kara newly formed sea ice increases local turbulent heat fluxes and modulates mid-to-high-latitude circulation over Eurasia through altered transient eddy activity and Rossby wave propagation, thus reinforcing the BDD. Numerical experiments using the ECHAM5 model and LBM simulations confirmed the atmospheric responses to these SST and sea ice anomalies. Additionally, BDD-related circulation anomalies trigger widespread temperature and precipitation extremes and may contribute to compound extreme events.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686195","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":"Land Surface Temperature Shows Negligible Difference Between Inside and Outside Photovoltaic Power Plants in China","authors":"Chunhui Duan,&nbsp;Cunbo Han,&nbsp;Wei Hu,&nbsp;Jiawei Liu,&nbsp;Yaoming Ma","doi":"10.1029/2026JD046444","DOIUrl":"https://doi.org/10.1029/2026JD046444","url":null,"abstract":"<p>The global rapid expansion of photovoltaic (PV) power plants has drawn considerable attention to their impacts on land surface temperature (LST), which is a crucial indicator of surface energy balance. However, previous studies mainly focused on individual plants or limited regions. In this study, the effects of ground-mounted PV power plants on LST across China have been investigated in detail. The analysis integrates Thermal and Reanalysis Integrating Moderate-resolution Spatial-seamless (TRIMS) LST with the land component of the fifth generation of European ReAnalysis (ERA5-Land), using a random forest regression model combined with the Shapley additive explanations (SHAP) method. The results show that PV power plants generally induce daytime warming (0.10°C) and nighttime cooling (−0.09°C) effects on LST relative to surrounding areas, and produce a nearly negligible daily warming (0.01°C) effect. Such effects are found in vegetated areas (cropland, woodland, grassland), particularly in woodlands. Daytime warming and nighttime cooling effects are the strongest in summer (0.29°C) and winter (−0.13°C), respectively. The daily effect is warming in summer (0.12°C) but cooling in winter (−0.05°C). Albedo, Normalized Difference Vegetation Index (NDVI), sensible heat flux, latent heat flux, wind speed, and downward shortwave radiation are identified as the key factors influencing LST differences between PV power plants and their surrounding areas (ΔLST). The contributions of these factors vary in both diurnal and seasonal cycles. These findings elucidate the local-scale climate feedback initiated by PV installations through land-atmosphere interactions, offering critical insights for the sustainable deployment of solar energy.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686196","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":"Chemical Composition of Atmospheric Brown Carbon From the Indo-Gangetic Plain: Evidence of Near-Infrared Absorption","authors":"Pooja Chaudhary,&nbsp;Arpit Awasthi,&nbsp;Raj Singh,&nbsp;Vinayak Sinha,&nbsp;Christopher P. West,&nbsp;Qiaorong Xie,&nbsp;Kyla Siemens,&nbsp;Janine Mahoski,&nbsp;Alexander Laskin,&nbsp;Baerbel Sinha","doi":"10.1029/2025JD044544","DOIUrl":"https://doi.org/10.1029/2025JD044544","url":null,"abstract":"<p>Brown Carbon (BrC), the light-absorbing fraction of organic aerosols, plays a critical yet underappreciated role in atmospheric radiative forcing. Over the Indo-Gangetic Plain (IGP), BrC is predominantly emitted from biomass burning associated with widespread biofuel use for heating and cooking, agricultural residue burning, and unregulated domestic waste burning. Despite its ubiquity, the molecular composition and optical behavior of BrC in this region is poorly understood. In this study, we present new molecular-level evidence revealing substantial Near-Infrared (NIR) light absorption by organic acids in the IGP. We investigated the chemical composition of nighttime BrC collected at a suburban site in the northwestern IGP by comparing two different seasons—post-monsoon and winter, and two wind-sectors—urban and rural. Aerosol samples were collected at the IISER Mohali Atmospheric Chemistry Facility, India. Compositional information was obtained by employing Direct-Analysis in Real-Time High-Resolution-Mass-Spectrometry to analyze samples of organic aerosols collected on the filter spots of a 7-wavelength aethalometer. Pronounced compositional differences appeared between urban-influenced and rural-influenced samples, although no significant seasonal variations were observed. Overall, organic aerosols in the region are dominated by nitrogen-containing species. Urban-influenced air-masses are strongly affected by open burning of domestic waste, as reflected by the abundance of reduced-nitrogen species. Notably, the presence of long-chain organic acids, observed particularly in urban-influenced samples, was found to enhance light absorption at longer wavelengths, extending into NIR, a spectral region traditionally attributed to black carbon (BC). This has critical implications for aerosol optical measurements, suggesting potential underestimation of BrC and overestimation of BC contributions.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686149","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":"Observing Systems Simulation Experiments of Hypothetical Hourly Global Coverage of Microwave Satellite Radiances: Imbalance and Adaptive Observation Error Inflation","authors":"Rakesh Teja Konduru,&nbsp;Jianyu Liang,&nbsp;Shigenori Otsuka,&nbsp;Takemasa Miyoshi","doi":"10.1029/2025JD044041","DOIUrl":"https://doi.org/10.1029/2025JD044041","url":null,"abstract":"<p>This study investigates the potential impacts of frequent global coverage of satellite microwave radiances using a global atmospheric data assimilation (DA) system. Observing Systems Simulation Experiments (OSSEs) were performed using the Local Ensemble Transform Kalman Filter with the Nonhydrostatic Icosahedral Atmospheric Model (NICAM). Three different observation time intervals are examined: hourly (1H), bi-hourly (2H), and six-hourly (6H). 6H mimics the current coverage of Advanced Microwave Sounding Unit-A in orbits. 1 and 2H show higher Root Mean Square Errors (RMSEs) for temperature compared to 6H due to dynamical imbalances indicated by the second time derivatives of sea level pressure. To mitigate the imbalances in 1H, we first inflate the observation error standard deviation in DA by 60% (1H-Rinfl) and successfully reduce imbalances by 5%–10% with the temperature RMSE decreased by 10%–15%. Next, we apply the Adaptive Observation Error Inflation (AOEI) method, which adjusts the observation error standard deviations online based on the innovation statistics. 1H with AOEI (1H-AOEI) reduces the dynamical imbalance and shows lower RMSE than that of 6H. 1H-AOEI also shows more skill in forecasting precipitation events with intensity &gt;2 mm/hr on small scales than 6H.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JD044041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Non-Classical Gravity-Wave Dynamics on Middle-Atmosphere Mean Flow and Solar Tides","authors":"T. Kühner,&nbsp;G. S. Völker,&nbsp;U. Achatz","doi":"10.1029/2025JD045506","DOIUrl":"https://doi.org/10.1029/2025JD045506","url":null,"abstract":"<p>Conventional gravity-wave (GW) parameterizations neglect three aspects of GW dynamics. Instead of momentum and entropy fluxes they use Eliassen-Palm fluxes, thereby neglecting the possibility that resolved flow are not in geostrophic and hydrostatic balance. They neglect the transience of the GW field and of the resolved flow, by determining at every time step equilibrium profiles of GW fluxes that would result if the vertical GW propagation were instantaneous. Moreover, they also do not take into account lateral GW propagation and horizontal GW fluxes. Because the prognostic GW model MS-GWaM does not need to make these assumptions, it has been used in the global weather and climate code ICON to investigate their consequences for the simulation of monthly mean zonal mean flows and of solar tides. All three aspects are found to influence the simulation results significantly. The mean circulation in the mesosphere and lower thermosphere is affected at all latitudes and in the stratosphere as well. This together with the directly modified GW forcing leads also to significant differences in the migrating and nonmigrating components of solar tides. Comparisons with tides retrieved from satellite data are most favorable if both aspects are taken into account. This argues for a correspondingly generalized treatment of GW dynamics in their parameterization, as an efficient alternative to GW permitting simulations.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JD045506","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147685994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can the Accumulated Precipitation Intensity and Structure Be Captured by CINRAD VCP21 Using Bi-Directional Optical Flow (BIO) Algorithm?","authors":"Mengdi Li,&nbsp;Youcun Qi,&nbsp;Zhida Yang,&nbsp;Zhe Zhang,&nbsp;Donghuan Li,&nbsp;Muqi Xiong,&nbsp;Xiaoyong Lu,&nbsp;Xun Li","doi":"10.1029/2026JD046321","DOIUrl":"https://doi.org/10.1029/2026JD046321","url":null,"abstract":"<p>This study evaluates the effectiveness of the Bi-directional Optical Flow (BIO) method in capturing accumulated precipitation intensity and structure by China New Generation Weather Radar (CINRAD) operated in volume coverage pattern 21 (VCP21) scan mode, aiming to improve the accuracy of radar quantitative precipitation estimation (QPE). The BIO method was analyzed across 13 precipitation events, including three types of precipitation events: convective, typhoon, and stratiform precipitation events. High-resolution X-band phased array radar QPE data and rain gauge observations were used to validate the precipitation intensity and structure obtained using the BIO method. The results of elliptical parameter analysis demonstrated that the BIO method's precipitation showed high positional accuracy, precise alignment of precipitation orientation, and spatial distribution closely consistent with original X-band phased array radar precipitation data. Statistical comparisons further highlighted that accumulated precipitation intensity of the BIO method (BIOQPE) significantly reduced errors compared to intensity from VCP21 mode, with an average decrease of 11.2% in RMSE, 14.0% in RMAE, and an average increase of 4.7% in CC across the 13 events. Particularly, BIOQPE provided superior accuracy and continuity in intensity and structure for convective and typhoon precipitation events. For stratiform precipitation, BIOQPE improved spatial continuity and demonstrated greater accuracy than original radar data. The results reveal that the BIO method is effective in describing precipitation intensity and structure within observations, and significantly improves the accuracy of accumulated precipitation, especially under limited temporal resolution conditions.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"131 8","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147686148","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}