Journal of Geophysical Research: Atmospheres最新文献

{"title":"From Sea to Summit: Investigating the Explicit Role of SST Increase for Regional and High-Altitude Climates in New Zealand","authors":"E. Kropač,&nbsp;T. Mölg,&nbsp;N. J. Cullen","doi":"10.1029/2025JD043572","DOIUrl":"https://doi.org/10.1029/2025JD043572","url":null,"abstract":"<p>The oceans around New Zealand are regional warming hotspots where sea surface temperature (SST) is rising much faster than the global average. This study uses a sensitivity experiment with a regional atmospheric model to investigate how ocean warming over the past decade (2010–2020) has influenced New Zealand's climate at different spatial scales, with particular attention to the highly sensitive alpine regions of the Southern Alps. The approach addresses the effects of an isolated SST increase, explicitly excluding broader systemic changes associated with global warming. Results suggest that rising SSTs have driven widespread thermodynamic responses, including increases in near-surface air temperature and humidity, particularly in autumn and summer. These responses have most likely affected circulation dynamics—such as changes in wind fields and moisture transport—that have modified the mesoscale flow regime near the Southern Alps, reshaping precipitation patterns and reducing foehn effects in the eastern lowlands. The dynamic responses, however, remain subject to uncertainty. Crucially, the impacts of the SST increase extend into the alpine environment, where surface warming is amplified and snowfall is reduced. Consequently, high-elevation climate regimes have shifted toward warmer and more humid conditions, contributing to greater rainfall dominance and potentially accelerated glacial melt. This study provides a process-based understanding of the influence of SST changes on both regional and high-altitude climate in New Zealand. The findings emphasize the potential for continued ocean warming to exacerbate high-elevation climate shifts and glacier retreat, with substantial implications for regional hydrology, ecosystems, and human activities.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JD043572","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144758530","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 Lateral Boundary Flows on Regional Convection-Permitting Simulations Over the Tibetan Plateau: A Global-Regional Integrated Modeling Study","authors":"Tianru Chen,&nbsp;Yi Zhang,&nbsp;Yiming Wang,&nbsp;Weihua Yuan","doi":"10.1029/2024JD042952","DOIUrl":"https://doi.org/10.1029/2024JD042952","url":null,"abstract":"<p>The GRIST model is used for the first time in a regional downscaling experiment based on the convection-permitting third-pole monsoon case. The simulations driven by external reanalysis data sets are assessed and compared with the global simulation through a rigorous global-regional integrated modeling approach. Additional regional simulations with boundary data taken from the global simulation reveal the critical role of cross-boundary flows in aligning regional model behaviors with global results. The study focuses on downscaling performance, global-regional comparisons, and the impact of lateral boundary flow. The downscaling simulations using different reanalysis data sets produce overall comparable large-scale circulation patterns and mean precipitation biases. Nudged lateral boundary conditions improve the circulation performance but result in mixed precipitation outcomes, including higher mean-state biases and artificial rainfall around the Tibetan Plateau area. Some intrinsic model biases (e.g., diurnal cycle and excessive light rainfall frequency) are consistent across global and regional simulations. Using explicit convection can address these limitations. Intense rainfall events and topographic precipitation errors show high sensitivity to lateral boundary flow variations, underscoring the complexity of interactions between regional dynamics and boundary flows. Systematic topographic precipitation biases persist but varying lateral boundary flows can regulate the magnitude. The results underscore the uncertainties associated with kilometer-scale downscaling simulations under strong lateral boundary flows particularly concerning small-scale intense and/or topographic rainfall events.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144758528","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 True Eddy Accumulation System for Measuring Trace Gas Flux: Practical Implementation and Evaluation Above a Forest","authors":"Takuya Saito,&nbsp;Ayaka Sakabe,&nbsp;Satoru Takanashi,&nbsp;Yoshiko Kosugi","doi":"10.1029/2025JD044412","DOIUrl":"https://doi.org/10.1029/2025JD044412","url":null,"abstract":"<p>The true eddy accumulation (TEA) technique for turbulent flux measurements is an alternative to the conventional eddy covariance (EC) technique for measuring trace gases that are difficult to measure by the EC technique. However, the TEA technique has rarely been applied to studies of air–surface gas exchange because of the limited availability of reliable instrumentation. In this study, we developed an air sampling system based on the TEA technique using fast-response mass flow controllers. The TEA system collects updrafts and downdrafts at sampling flow rates proportional to the vertical wind speed, unless the wind speed exceeds a certain threshold. We evaluated the TEA system above a temperate forest in Japan from May to December 2022 by comparing CO₂ fluxes measured by the TEA system with those measured using EC. The comparison showed a moderate correlation (<i>R</i> = 0.86) with a small but significant negative bias in the TEA system (2%), likely because of the wind threshold. Our results suggest that the TEA system is a promising alternative for measuring turbulent fluxes of trace gases.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JD044412","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751510","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":"Comprehensive Analysis of Bias in TEMPO NO2 Column Densities Through Pandora Observations","authors":"Masoud Ghahremanloo,&nbsp;Caroline Nowlan,&nbsp;Gonzalo González Abad,&nbsp;Cecilia Garraffo,&nbsp;Xiong Liu,&nbsp;Huiqun Wang,&nbsp;Barron Henderson,&nbsp;Eric Baumann,&nbsp;Lukas Valin,&nbsp;Jeffrey A. Geddes,&nbsp;Xiaoyi Zhao","doi":"10.1029/2025JD044150","DOIUrl":"https://doi.org/10.1029/2025JD044150","url":null,"abstract":"<p>Tropospheric Emissions: Monitoring of Pollution (TEMPO) is the first geostationary satellite instrument to monitor air pollutants across North America. This study uses Pandora observations to analyze the bias in TEMPO Level-3 total column density of NO₂ (TOTNO₂) from August 2023 to December 2024. TEMPO achieves high accuracy at 5% cloud-filtering threshold: correlation coefficient (R) of 0.86, index of agreement (IOA) of 0.91, mean absolute bias (MAB) of 1.423 × 10¹⁵ molecules/cm², and a percentage MAB (MABP) of 23.1%, corresponding to a 12% underestimation. Accuracy decreases when pixels with greater cloud-cover are included. Solar zenith angle (SZA) of 10–20° yields the highest accuracy (R: 0.87, MABP: 22.7%), whereas SZAs of 70–80° yield the lowest (R: 0.71, MABP: 35.2%). Consequently, early-morning or near-sunset observations are less reliable than midday. This discrepancy could stem from inaccurate simulation of diurnal variations in the boundary-layer height in the a-priori, and from larger uncertainties in radiative transfer at high SZAs. TEMPO overestimates TOTNO₂ at low NO₂ levels and underestimates at high levels, with maximum biases of +16% (low) and −31% (high), respectively. Station-to-station performance varies considerably, with R ranging from 0.29 to 0.84 and MABP from 14.9% to 49.3%. Stations situated at higher altitudes relative to the ground show reduced agreement with TEMPO, as Pandora cannot detect NO₂ below the instrument's altitude, whereas TEMPO retrieves the full column. Validation of TEMPO TOTNO₂ at TROPOMI overpass time indicates that TEMPO's performance relative to Pandora (IOA: 0.93, MABP: 22.3%) closely matches that of TROPOMI (IOA: 0.92, MABP: 20.1%).</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JD044150","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751414","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":"Twenty Years of Global Stratospheric Fluorine Inventories From Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) Measurements","authors":"N. Raymond,&nbsp;P. Bernath,&nbsp;C. Boone,&nbsp;M. Chipperfield","doi":"10.1029/2024JD042298","DOIUrl":"https://doi.org/10.1029/2024JD042298","url":null,"abstract":"&lt;p&gt;We present fluorine inventories calculated for twenty years (2004–2023) and five latitude bands (82°–60°N, 60°–30°N, 30°N–30°S, 30°–60°S, and 60°–82°S) at altitudes from the surface up to 55 km. The inventories were calculated using the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) version 5.2 retrievals of the volume mixing ratios (VMRs) of 15 fluorine-containing species. Of these 15 species, 3 are product gases: &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mtext&gt;HF&lt;/mtext&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $text{HF}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, &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;COF&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{COF}}_{2}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mtext&gt;COClF&lt;/mtext&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; $text{COClF}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, and 12 are source gases: &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;SF&lt;/mtext&gt;\u0000 &lt;mn&gt;6&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{SF}}_{6}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, PFC-14 (&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;CF&lt;/mtext&gt;\u0000 &lt;mn&gt;4&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{CF}}_{4}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;), CFC-11 (&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;CCl&lt;/mtext&gt;\u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;mi&gt;F&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{CCl}}_{3}mathrm{F}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;), CFC-12 (&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;CCl&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;msub&gt;\u0000 &lt;mi&gt;F&lt;/mi&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{CCl}}_{2}{mathrm{F}}_{2}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;), CFC-113 (&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;CClF&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 ","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD042298","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751509","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":"Microphysical and Kinematical Characteristics of Merged and Isolated Convective Cells Over the Complex Terrain of the Taipei Basin","authors":"Jyong-En Miao,&nbsp;Ming-Jen Yang,&nbsp;Kristen L. Rasmussen,&nbsp;Michael M. Bell,&nbsp;Hung-Chi Kuo,&nbsp;Ting-Yu Cha","doi":"10.1029/2024JD042375","DOIUrl":"https://doi.org/10.1029/2024JD042375","url":null,"abstract":"<p>This study investigates the microphysical and kinematic characteristics in extreme afternoon thunderstorm rainfall during Taiwan-Area Heavy rain Observation and Prediction Experiment/Prediction of Rainfall Extremes Campaign In the Pacific IOP 2. The high-quality S-Pol radar observations and multi-Doppler winds provided valuable information about the convective organization over complex terrain. There were two episodes of heavy rainfall in this event. Episode 1 (1200–1400 LST, Local Standard Time) featured multiple cell merger (MCM) favored by terrain-induced circulation. Around the time of MCM, the enhanced ZDR region (&gt;1 dB) broadened horizontally to ∼8 km in width at 5.5 km above mean sea level (AMSL). Afterward, maximum vertical velocity increased dramatically to ∼20 m s⁻¹ and graupel reached up to 12 km AMSL. In contrast, Episode 2 (1500–1700 LST) exhibited isolated cells with weak updrafts (&lt;10 m s⁻¹) and more snow aloft. The merged ZDR columns coincided with MCM occurrence, preceding peaks in both vertical velocity and rainfall intensity. Building on emerging research investigating the relationship between ZDR column size and severe weather in the US, this study suggests that wide merged ZDR columns may be relevant to severe storms over complex terrain in Taiwan, highlighting their potential utility as indicators of storm intensification.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD042375","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144751502","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":"Characteristics and Predictability of Extreme Precipitation Related to Atmospheric Rivers, Mesoscale Convective Systems, and Tropical Cyclones in the U.S. Southeast","authors":"Suma B. Battula,&nbsp;Jason M. Cordeira,&nbsp;F. Martin Ralph","doi":"10.1029/2024JD042471","DOIUrl":"https://doi.org/10.1029/2024JD042471","url":null,"abstract":"<p>The Southeastern United States (SEUS) region has lower extreme quantitative precipitation forecast (QPF) skill compared to the northeastern or western United States. Previous studies have reported that the extreme precipitation events (EPEs) with high integrated vapor transport (IVT) have higher QPF skill than those with low IVT in the SEUS. We hypothesize that this extreme QPF skill is influenced by different storm types, such as atmospheric rivers (ARs), mesoscale convective systems (MCSs), and tropical cyclones (TCs), occurring within various synoptic patterns. This study investigates pattern-wise QPF skill and the contribution of storm types to EPEs in the SEUS. Six synoptic patterns associated with EPEs were identified from 2001 to 2019. These patterns exhibited a distinct seasonality: three occurred in the cool season, two in the warm season, and one in the transition season. Approximately 35% of the EPEs in the cool season, 24% in the transition season, and 29% in the warm season are associated with coincident ARs and MCSs. Pattern-wise QPF skill derived from the GEFS reforecast dataset illustrated that the cool season pattern, characterized by high IVT and frequency of ARs, has higher QPF skill. In contrast, the warm season pattern with high convective available potential energy and integrated water vapor has lower QPF skill across multiple lead times. In addition, patterns with higher frequency of ARs or coincident ARs and MCSs have better predictability than those with isolated MCSs. These results provide insight into the contribution of storm types to EPEs and their predictability in the SEUS.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JD042471","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144740245","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":"The Mechanism of Interhemispheric Coupling Revealed by a Gravity Wave-Permitting General Circulation Model","authors":"H. Okui,&nbsp;K. Sato,&nbsp;S. Watanabe","doi":"10.1029/2025JD043763","DOIUrl":"https://doi.org/10.1029/2025JD043763","url":null,"abstract":"<p>Interhemispheric coupling (IHC) is the positive correlation between temperatures in the polar winter stratosphere and the polar summer upper mesosphere and the lower thermosphere. Over the past two decades, several mechanisms have been proposed to explain the IHC. However, a consensus on the mechanism is yet to be fully reached, particularly regarding the role of gravity waves (GWs). We conduct hindcast simulations for seven boreal winters using a GW-permitting general circulation model encompassing the whole neutral atmosphere. The model is initialized through spectral nudging to state-of-the-art reanalysis data of identical vertical coverage. Treating the 7-year averages of the model outputs as a climatology, the IHC is investigated as a sequential evolution of anomalies relative to it. The results showed that consequential interplay of GWs and quasi-two-day waves in the summer mesosphere is the key driver of the IHC, as is consistent with Yasui et al. (2021, doi: 10.1175/jas-d-21-0045.1) except for the final step toward the summer pole facilitated by primary GWs in the Antarctic. These waves are filtered by an anomalously weak westward jet due to a temperature gradient caused by planetary wave forcing, considered to be quasi-two-day waves. The mechanism is mostly applicable to both types of IHC events: those associated with sudden stratospheric warming and those with vortex intensification. Meanwhile, comparisons across the seven boreal winters indicate vulnerabilities in specific processes underlying the mechanism. In the reanalysis, it is suggested that GW parameterizations underestimate the GW forcing anomalies, but analysis increments reduce this discrepancy.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JD043763","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144725544","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":"Significant Contributions of Regional Transport to Sulfate Aerosols During Haze Events in Northern China Plain: Constrained by Sulfur Isotopic Compositions","authors":"Yu-Chi Lin,&nbsp;Mei-Yi Fan,&nbsp;Mingyuan Yu,&nbsp;Abudurexiati Abulimiti,&nbsp;Feng Xie,&nbsp;Rongshuang Xu,&nbsp;Yan-Lin Zhang","doi":"10.1029/2025JD043716","DOIUrl":"https://doi.org/10.1029/2025JD043716","url":null,"abstract":"<p>Regional transport is a significant source of sulfate (SO₄²⁻) aerosols, which frequently induces haze formation in the Northern China Plain (NCP). Quantification of regional transport to SO₄²⁻ using chemical transport models (CTMs) is debated due to uncertainties in SO₂ emissions and SO₄²⁻ formation mechanisms incorporated in the CTMs. In this study, sulfur isotope ratios in sulfate (δ³⁴S-SO₄²⁻) were measured at Gucheng, a heavily polluted city in the NCP, to differentiate local emissions from regional transport to sulfate. The δ³⁴S-SO₄²⁻ values varied from 2.5 to 6.5‰, with a mean of 4.6 ± 1.1‰. The lower δ³⁴S-SO₄²⁻ values were observed in the haze events, attributed to regional transport from high-SO₂ emission regions, where coal materials typically exhibit declined δ³⁴S values. The fractionation factors (α³⁴S_g→p) of δ³⁴S for SO₂ to SO₄²⁻ conversion were estimated to be 3.6 ± 1.1‰. Considering the α³⁴S_g→p, the quantified formation mechanisms indicated that transition metallic ions (TMIs)-catalyzed O₂ oxidation dominated sulfate formation, contributing 34%, followed by NO₂ (27%), OH (23%), and H₂O₂/O₃ oxidation pathways (16%). Local coal burning, vehicle emissions, and oil combustion contributed 58%, 16%, and 9% to sulfate, respectively. The remaining 17% of sulfate was contributed by regional transport (mainly coal burning) with enhancements in the specific haze events. Although uncertainties remained in the estimations, our findings did suggest that strict control in SO₂ emissions from local and regional coal combustion along with TMIs emissions from the steel industry was crucial for reducing sulfate concentrations in this NCP city.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144725698","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":"Atmospheric Circulation Impacts on Terrestrial Atmospheric Nitrogen Deposition Under Growing Imbalance of Regional Nitrogen Emissions and Deposition","authors":"Qiulan He,&nbsp;Ruowen Yang,&nbsp;Pierre Gentine,&nbsp;Shangfeng Chen,&nbsp;Lei Cai,&nbsp;Weiyu Shi","doi":"10.1029/2024JD042988","DOIUrl":"https://doi.org/10.1029/2024JD042988","url":null,"abstract":"<p>Atmospheric nitrogen deposition has broad implications for global ecosystems and human health. It is largely influenced by local weather conditions and atmospheric transport, which are in turn controlled by large-scale atmospheric circulation patterns. Because of the absence of long-term atmospheric nitrogen deposition data series, the mechanisms of interannual variation of nitrogen deposition are still poorly understood. Here, we investigate relationships between atmospheric nitrogen deposition and atmospheric circulation variability and explore the underlying mechanisms. We find that there is a growing imbalance between regional nitrogen emissions and deposition in global hotspots. Atmospheric nitrogen deposition variations exhibit significant relationships with atmospheric circulation modes, with predominant influences from the El Niño-Southern Oscillation (ENSO). Additionally, we captured significant nitrogen deposition anomalies during different phases of ENSO years by altering global temperature, precipitation, and atmospheric circulation. Significant effects of ENSO on atmospheric nitrogen deposition were observed in the Eastern United States, Eastern Europe, and East Asia.</p>","PeriodicalId":15986,"journal":{"name":"Journal of Geophysical Research: Atmospheres","volume":"130 15","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144725700","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}