Atmospheric and Oceanic Science Letters最新文献

{"title":"Observation of Typhoon Trami (2024)-induced energy cascade from near-inertial waves to diurnal internal tides","authors":"Letian Chen,&nbsp;Ze Zhang,&nbsp;Yifei Jiang,&nbsp;Xiaojiang Zhang,&nbsp;Jiagen Li,&nbsp;Weimin Zhang,&nbsp;Huizan Wang","doi":"10.1016/j.aosl.2025.100712","DOIUrl":"10.1016/j.aosl.2025.100712","url":null,"abstract":"<div><div>Energy transfers among internal waves in the northern South China Sea are not well characterized, particularly during typhoons, owing to the lack of in situ observations. Based on high-resolution mooring data collected during Typhoon Trami (2024), this study reveals the occurrence of robust vertical energy redistribution among diurnal internal tides (D1 ITs) and near-inertial waves (NIWs). Strikingly, the typhoon not only amplified the NIW energy but also triggered an unexpected surge in the D1 IT energy. The observed average net energy transfer rate of 1 × 10⁻⁷ W kg⁻¹ from typhoon-forced NIWs to D1 ITs occurred at water depths of 120–170 m. Further bispectral analysis indicated that the energy transfer is driven by nonlinear wave–wave interaction. These results reveal the existence of a new energy transfer pathway—from atmospheric forcing to D1 ITs—and redefine the redistribution of the internal wave energy during extreme weather events.</div><div>摘要</div><div>台风期间内波间的能量传递特征及机制尚未得到清晰揭示. 本研究利用 2024 年南海北部“潭美”台风期间获取的高分辨率潜标观测数据, 发现全日内潮与近惯性内波之间存在显著的垂直能量串级现象. 台风作用下, 观测发现在近惯性波能量显著增强的同时, 全日内潮能量亦出现激增; 在 120–170 米深度范围的水层, 观测到台风强迫下近惯性波向全日内潮的平均净能量传递率达 1 × 10⁻⁷ W kg⁻¹. 双谱分析结果进一步证实, 这一能量传递过程由非线性波-波相互作用主导驱动. 上述结果揭示了“大气强迫至全日内潮”这一全新的内波能量传递路径, 进而重新界定了极端天气事件作用下内波能量的再分配规律.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100712"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Classification of marine heatwaves in the South China Sea and their thermodynamic features","authors":"Rongwang Zhang ,&nbsp;Yujie Cheng ,&nbsp;Xin Wang","doi":"10.1016/j.aosl.2025.100662","DOIUrl":"10.1016/j.aosl.2025.100662","url":null,"abstract":"<div><div>The frequency of marine heatwaves (MHWs) in the South China Sea (SCS) has increased recently. However, the relative roles of thermal and dynamic processes regulating the changes of SCS MHWs remain an open question. This study examines all long-lived MHWs (&gt; 10 days) in the SCS from 1982 to 2021, categorizing them into intensified and attenuated MHWs based on the overall trend of sea surface temperature during an MHW event. A mixed-layer heat budget analysis reveals that the thermal processes primarily driven by the latent heat flux are crucial in modulating the SCS MHWs, particularly for attenuated MHWs. However, under intensified conditions, the proportions of dynamically dominated MHWs (40 %) is approximately comparable to that of thermally dominated ones (47 %). This study highlights the significance of dynamic processes in shaping SCS MHWs and discusses the potential impacts induced by tropical cyclones on these MHWs.</div><div>摘要</div><div>近年来南海海洋热浪发生频率显著上升, 但调控其变化的热力与动力过程的相对作用尚不明确. 本研究分析了1982至2021年的南海海洋热浪事件, 根据海洋热浪期间海表温度的变化趋势将其划分为增强型和减弱型两类. 混合层热收支分析表明, 由潜热通量主导的热力过程对调控南海海洋热浪 (尤其是衰减型) 至关重要. 然而, 在增强型海洋热浪中, 动力过程主导的事件比例 (40 %) 与热力主导型 (47 %) 近乎相当. 本研究强调了动力过程在塑造南海海洋热浪中的重要性, 并探讨了热带气旋对南海海洋热浪可能产生的影响.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100662"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combined LFS and ConvLSTM to forecast marine heatwaves: a case study","authors":"Bowen Zhao ,&nbsp;Tao Zhang ,&nbsp;Yanfeng Wang ,&nbsp;Pengfei Lin ,&nbsp;Hailong Liu ,&nbsp;Ping Huang ,&nbsp;Wei Huang ,&nbsp;Pengfei Wang ,&nbsp;Yiwen Li","doi":"10.1016/j.aosl.2025.100690","DOIUrl":"10.1016/j.aosl.2025.100690","url":null,"abstract":"<div><div>Marine heatwaves (MHWs) in the South China Sea (SCS) significantly impact marine ecosystems and socioeconomic development, yet accurately forecasting MHWs remains a challenge. This study developed an upper-ocean temperature forecasting model based on ConvLSTM for the northern SCS and, in conjunction with the ocean forecasting system LICOM Forecast System (LFS), constructed a hybrid Fusion model using Wasserstein-Distance optimization. The ability of these three models to forecast key MHW metrics with a 10-day lead was assessed during the summer of 2022 in the SCS. Overall, the Fusion model takes advantage of LFS and ConvLSTM, providing superior forecasts for both the duration and intensity of MHWs in the southern SCS. LFS (ConvLSTM) overestimates (underestimates) the duration of MHWs and all models exhibit limitations in forecasting the intensity of MHWs in part of the SCS. The Fusion model’s superior forecast skill for MHWs may be attributable to its more realistic representation of the upper-ocean thermal structure with shallower mixed-layer depths during MHWs. This study highlights that combining the deep learning technique with a dynamical model can improve MHW forecasting and has certain physical interpretability.</div><div>摘要</div><div>海洋热浪 (MHW) 严重威胁中国南海生态与经济, 亟需提高MHW预测能力. 本研究基于海洋再分析资料, 利用ConvLSTM构建上层海温深度学习预报模型, 并与LICOM海洋环境预报系统 (LFS) 融合, 建立订正模型 (Fusion). 评估ConvLSTM, LFS和Fusion对2022年南海夏季MHW持续时间和平均强度的预报技巧表明: 1) Fusion技巧最优; 2) LFS系统性高估, ConvLSTM系统性低估MHW持续时间; 3) 三个模型对部分海域的MHW平均强度预报存在局限. Fusion较高的MHW预报技巧可能与更合理的上层温度垂直结构有关. 本研究表明, 融合深度学习与动力模式可有效改进南海MHW预报, 并具物理可解释性.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100690"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An assessment of mesoscale eddies simulated by a global eddy-resolving ocean forecast system in the South China Sea","authors":"Baoxin Feng ,&nbsp;Mengrong Ding ,&nbsp;Lingling Xie ,&nbsp;Pengfei Lin ,&nbsp;Weipeng Zheng ,&nbsp;Hailong Liu","doi":"10.1016/j.aosl.2025.100706","DOIUrl":"10.1016/j.aosl.2025.100706","url":null,"abstract":"<div><div>This research evaluates the performance of an eddy-resolving forecast system (LFS) in simulating mesoscale eddies over the South China Sea (SCS) through a comparative analysis with satellite observations and the reanalysis dataset from the Global Ocean Physics Reanalysis product (CMEMS). The findings indicate that the spatial characteristics of eddy kinetic energy, number, and amplitude of coherent mesoscale eddies simulated by LFS exhibit a reasonable agreement with satellite observations. The reproduced seasonal variations are also comparable to outputs from the CMEMS reanalysis dataset. Nevertheless, certain systematic biases have also been identified. In the SCS, LFS generates approximately 17 % fewer eddies than observed. Such biases are also evident in the CMEMS reanalysis dataset. Similar to the statistics shown in the CMEMS reanalysis dataset, both cyclonic and anticyclonic eddies are significantly weaker in LFS compared to the observations. Additionally, the composite three-dimensional structures of mesoscale eddies simulated by LFS exhibit a remarkable similarity to those identified in the CMEMS reanalysis datasets. This work lays the foundation for further studies using LFS to investigate the predictability of mesoscale eddies and enhance the accuracy of simulations.</div><div>摘要</div><div>本文基于卫星观测数据与高分辨率再分析数据 (CMEMS), 对由中国科学院大气物理研究所自主研发的全球涡分辨率海洋预报系统 (LFS) 所模拟的南海中尺度涡进行了系统评估. 研究结果表明, LFS模拟的南海涡动能, 涡旋数量, 涡旋振幅等指标的空间分布特征均与卫星观测结果表现出良好的一致性. 此外, 其模拟的季节性变化特征以及涡旋的温盐三维结构特征, 也与 CMEMS再分析数据集结果高度吻合. 然而, 研究也揭示了一些系统性偏差: 在南海区域, LFS模拟的中尺度涡数量比观测结果约少17%, 这一偏差在CMEMS再分析数据集中同样显著.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100706"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climatological characteristics of the extratropical transition of tropical cyclones along different tracks in the western North Pacific (1979–2022)","authors":"Shanshan Li ,&nbsp;Lei Chen ,&nbsp;Xihui Gu","doi":"10.1016/j.aosl.2025.100652","DOIUrl":"10.1016/j.aosl.2025.100652","url":null,"abstract":"<div><div>Based on datasets from the International Best-Track Archive for Climate Stewardship (IBTrACS) and the fifth major global reanalysis produced by ECMWF (ERA5), the authors found that 29% of tropical cyclones (TCs) in the western North Pacific underwent extratropical transition (ET) from 1979 to 2022, with the frequency of ET events showing a slow decreasing trend. The extratropical transition tropical cyclones (ETCs) are classified into four clusters using the <em>k</em>-means clustering method based on their track patterns: recurving ETCs, westward ETCs, northwestward ETCs, and abnormal track ETCs. The transition process of recurving ETCs mostly occurs after the recurvature is completed, while 63.7% of the westward ETCs complete their transition after landfall. Abnormal track ETCs undergo transition over high-latitude oceans. Northwestward ETCs have the longest duration and slowest transition speed during the ET period, resulting in a prolonged impact. The ET process occurs at the edges of the western Pacific subtropical high (WPSH), with higher frequency during westward extension and lower during eastward retreat. While westward ETCs transition through surface friction effects, others complete ET in the northwest baroclinic zone of the WPSH.</div><div>摘要</div><div>本研究基于国际气候管理最佳路径档案(IBTrACS)和欧洲中期天气预报中心第五代再分析数据集(ERA5), 发现1979−2022年间西北太平洋有29%的热带气旋经历了温带变性(ET)过程, 且ET事件的发生频率呈缓慢下降趋势. 通过<em>k</em>-means聚类方法, 将变性的热带气旋(ETCs)按路径特征划分为四类: 转向路径ETCs, 西移路径ETCs, 西北移路径ETCs和异常路径ETCs. 转向路径ETCs主要在完成转向后开始变性. 西移路径ETCs大多数在登陆后完成变性(63.7%). 异常路径ETCs通常在高纬度洋面完成变性. 西北移路径ETCs在变性期间所用时间最长, 移动速度较慢, 因此影响持续时间较长. ET过程均发生在西太平洋副热带高压(WPSH)边缘, WPSH西伸时ET频率较高, 东退时频率较低. 除西移路径ETCs受地表摩擦主导外, 其他类型多在WPSH西北侧的强斜压区完成转变.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100652"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disentangling the relative contributions of vertical pumping and horizontal transport to water-property anomalies within eddy cores in the southern Indian Ocean","authors":"Zhan Lian ,&nbsp;Kang Xu","doi":"10.1016/j.aosl.2025.100707","DOIUrl":"10.1016/j.aosl.2025.100707","url":null,"abstract":"<div><div>The eddies in the southernmost southern Indian Ocean exert major dynamical and biogeochemical influences on the Earth system. Therefore, disentangling the relative contributions of vertical pumping and horizontal transport to water-property anomalies in the eddy cores is of fundamental importance. Here, the authors introduce a temperature–salinity gradient-ratio approach (the “<em>R</em>-method”) that compares vertical and meridional gradients to quantitatively separate the two processes. Application of the R-method to three-dimensional Argo observations reveals that horizontal transport, rather than vertical pumping, predominantly governs the observed temperature and salinity anomalies within eddy cores in the SIO. Independent theoretical estimations based on background meridional gradients, together with composites formed on isopycnal surfaces, further corroborate this conclusion. The results challenge the conventional assumption that vertical pumping invariably controls eddy-core property anomalies and demonstrate the utility of the <em>R</em>-method for diagnosing eddy impacts in climate and biogeochemical studies.</div><div>摘要</div><div>南印度洋最南端的涡旋对整个地球系统的动力学和生物地球化学过程具有重大影响. 因此, 厘清垂直抽吸与水平输送对涡旋中心水体性质异常的相对贡献具有重要意义. 本研究提出了一种温-盐梯度比值方法 (“<em>R</em>方法”), 即通过比较海水温盐的垂向梯度比值与经向梯度比值, 可定量区分垂直抽吸与水平输送对温盐异常的相对贡献. 本研究将该方法应用于三维 Argo 观测资料后发现, 在南印度洋最南端区域内, 观测到的涡旋中心温盐异常主要由水平输送而非垂直抽吸所主导. 基于背景经向梯度的理论估算, 以及按等密度面合成的结果, 进一步验证了这一结论. 本研究结果表明, 传统假设“涡旋中心的温盐异常始终由垂直抽吸控制”并不成立. 研究结果还展示了利用<em>R</em>方法诊断涡旋水平和垂向贡献在气候与海洋生态研究中的应用前景.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100707"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parametric sensitivity analysis of East Asian summer-mean precipitation simulations by perturbed parameter ensemble experiments in CAM6","authors":"Yuxin Jiang,&nbsp;Lin Chen,&nbsp;Haoqian Li,&nbsp;Yesheng Zhu","doi":"10.1016/j.aosl.2025.100667","DOIUrl":"10.1016/j.aosl.2025.100667","url":null,"abstract":"<div><div>This study investigated the impacts of key parameters in CAM6’s deep convection and cloud physics schemes on the simulation of summer-mean precipitation over East Asia through conducting perturbed parameter ensemble (PPE) experiments. Utilizing the experimental platform of CAM6, a suite of 128 PPE simulations spanning 1979–2014 were generated through simultaneously perturbing 12 selected parameters. Using EOF analysis, this study firstly extracted the first two leading modes of the precipitation simulation biases. The authors further pinpointed the most critical parameters that have the most influential effects on the precipitation simulation biases, through conducting generalized linear model analysis. The first leading mode of precipitation simulation biases is primarily influenced by parameters from the cloud physics scheme, including the linear effects of <em>dcs</em> and <em>eii</em>, and the nonlinear effect of <em>rhminl</em>*<em>dcs</em>. These parameters influence the simulated total precipitation (PrecT) mainly by altering the large-scale precipitation (PrecL). The second leading mode is predominantly governed by the convection scheme parameter <em>dmpdz</em>, reflecting a competition between the changes in convective precipitation (PrecC) and PrecL in response to variations in <em>dmpdz</em>. An increase in <em>dmpdz</em> induces decreased PrecC and increased PrecL in East Asia, and both of the changes collectively shape the ultimate PrecT response to the adjusted <em>dmpdz</em>. Lastly, it is noteworthy that the nonlinear effect due to the interaction among parameters warrants attention when concurrently adjusting multiple parameters, and the precipitation biases from the PPE simulations resemble those identified through EOF analysis on the AMIP simulations, implying our findings may provide potential reference for other AGCMs.</div><div>摘要</div><div>本研究利用CAM6大气模式, 通过开展扰动参数集合 (PPE) 试验, 研究了CAM6中深对流方案和云物理方案的关键参数对东亚 (EA) 夏季平均降水模拟的影响. 通过同时扰动十二个关键参数, 本文开展了包含128个成员的PPE模拟试验. 本文首先利用EOF方法提取了降水模拟偏差的前两个主导模态. 进一步, 通过广义线性模型 (GLM) 分析, 甄别出了对降水模拟偏差影响最为关键的核心参数. 降水模拟偏差的第一主导模态主要受云物理方案参数的影响, 包括参数dcs和eii的线性效应, 以及参数rhminl*dcs的非线性效应. 这些参数主要通过改变大尺度降水 (PrecL) 来影响模拟的总降水 (PrecT) . 第二主导模态则主要由深对流方案参数dmpdz所主导, 它反映了当dmpdz变化时, 对流降水 (PrecC) 和PrecL变化之间的竞争关系. 增加dmpdz会导致东亚地区PrecC减少而PrecL增加, 这两种变化共同塑造了PrecT对dmpdz变化的最终响应. 值得指出的是, 当同时调整多个参数时, 参数间相互作用产生的非线性效应值得关注. 此外, 本文PPE模拟得到的降水偏差与AMIP模式非常相似, 这意味着研究结果可能为其他大气环流模式提供一定的科学参考.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100667"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of an enhanced mountain-to-plain convective storm based on potential divergence and the advection of potential instability","authors":"Wenjing Cheng ,&nbsp;Daoyong Yang ,&nbsp;Lingkun Ran ,&nbsp;Kuo Zhou ,&nbsp;Yanli Chu","doi":"10.1016/j.aosl.2025.100656","DOIUrl":"10.1016/j.aosl.2025.100656","url":null,"abstract":"<div><div>The enhanced mountain-to-plain convective storms in Beijing on 22 May 2021 were simulated using the high-resolution Weather Research and Forecasting model, enabling detailed analyses of convective instability characteristics and underlying causes of stability variations. Generalized potential temperature outperformed traditional potential temperature and equivalent potential temperature in capturing instability variations associated with mid-level latent heating and near-surface evaporative cooling. Local instability variance was primarily governed by potential divergence and the advection of potential instability, with these factors exhibiting out-of-phase distributions. Prior to the onset of heavy precipitation, intense downdrafts transported unstable air from higher levels into more stable regions at lower levels, increasing local near-surface instability, which contributed to the formation of heavy precipitation. During the heavy precipitation stage, vertical divergence between slantwise updrafts and downdrafts in the low–middle stable layers led to destabilization, supporting sustained convective development within the precipitation area. At the leading edge of the heavy precipitation, instability enhancement was primarily driven by vertical advection, and less stable air in the lower levels was transported upward, enhancing instability at higher levels.</div><div>摘要</div><div>针对2021年5月22日发生在北京地区的一次雷暴下山增强的过程, 利用WRF模式进行高分辨率数值模拟. 在成功模拟下山对流发生, 增强和移动的基础上, 对该过程中位势不稳定特征以及引起位势稳定度变化的原因进行诊断分析. 研究结果表明, 广义位温在识别由潜热加热与蒸发冷却引起的不稳定性变化方面, 优于传统的位温和相当位温. 通过对位势稳定度趋势方程的诊断分析发现, 局地位势不稳定的变化主要受位势散度和位势不稳定平流的主导, 两者在空间呈反位相分布. 在强降水开始前, 强烈的下沉气流将高层的不稳定空气输送到较为稳定的低层, 导致近地面不稳定性增加, 为强降水的形成提供了有利条件. 在强降水阶段, 低中层大气层结稳定, 同时倾斜上升气流和下沉气流之间的垂直辐散导致了大气向不稳定变化, 维持了对流的持续发展. 在强降水的前沿, 主要由垂直平流驱动不稳定性增加, 低层不稳定空气被向上输送, 增强了高层的不稳定性.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100656"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 refined oceanic model resolution on the simulation of Atlantic meridional overturning circulation in LICOM3","authors":"Xiaowei Wang ,&nbsp;Yongqiang Yu ,&nbsp;Zipeng Yu ,&nbsp;Pengfei Lin","doi":"10.1016/j.aosl.2025.100615","DOIUrl":"10.1016/j.aosl.2025.100615","url":null,"abstract":"<div><div>The present study compares the Atlantic Meridional Overturning Circulation (AMOC) in the North Atlantic from two simulations by an oceanic general circulation model with 1° × 1° and 0.1° × 0.1° resolution, respectively, which explores the sensitivity of AMOC to the resolution. The ocean model is the latest version of the LASG/IAP Climate System Model (LICOM3), and it is forced with atmospheric data from phase 2 of the Ocean Model Intercomparison Project (OMIP2). Comprehensive comparison between the two simulations indicates that the simulated AMOC is highly sensitive to the spatial resolution. The high-resolution model (LICOM-H) simulates a deeper mixed-layer depth (MLD), due to increased surface salinity, than that in the low-resolution model (LICOM-L) in the Labrador Sea, and it also has stronger AMOC strength (the maximum climatic mean AMOC from 1958 to 2018 is 23.4 Sv for LICOM-H and 21.2 Sv for LICOM-L) and larger variability of AMOC index (2.3 Sv for LICOM-H and 1.7 Sv for LICOM-L). These differences can mainly be attributed to two main dynamic processes that benefit from high resolution. Firstly, LICOM-H can simulate much stronger boundary currents (∼0.6 m s⁻¹) than LICOM-L (0.3 m s⁻¹) in the upper ocean, which leads to saltier and warmer seawater being transported to the Labrador Sea, where it enhances deep convection. Secondly, in LICOM-H, the stronger variability of AMOC is related to the higher sensitivity of the MLD and transformation to the prescribed atmospheric forcing in the Labrador Sea.</div><div>摘要</div><div>本研究关注大西洋经圈翻转环流 (AMOC) 对分辨率的敏感性, 比较了大气物理研究所自主发展的海洋环流模式LICOM (LASG/IAP Climate system Ocean Model) 不同分辨率版本对AMOC的模拟结果, 两个版本分辨率分别为1° × 1°和0.1° × 0.1°. LICOM高分辨版本模拟的AMOC强度和变率较低分辨率版本明显增加, 而且在拉布拉多海也模拟出了更深的混合层深度. 在上层海洋, 高分辨率版本可以模拟比低分辨率版本强得多的边界流, 这导致更多高盐海水被输送到拉布拉多海, 增强了该区域的深对流. 在高分辨率版本中, AMOC较强的变率与拉布拉多海混合层深度较高的变率和模式对大气强迫更敏感的响应有关.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100615"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climate change projections in Central Asia based on the CORDEX-CA-II high-resolution simulations","authors":"Yanjin Mao ,&nbsp;Ping Li ,&nbsp;Xianchun Chen ,&nbsp;Libin Huang ,&nbsp;Xiaorui Niu","doi":"10.1016/j.aosl.2025.100660","DOIUrl":"10.1016/j.aosl.2025.100660","url":null,"abstract":"<div><div>This study provides potential climate projections for Central Asia (CA) based on multi-regional climate model (RCM) outputs from the Coordinated Regional Climate Downscaling Experiment for Central Asia (CORDEX-CA-II). Despite some systematic biases, all RCMs effectively capture the main features of observed temperature and precipitation means and extremes over CA, with notable variations in model performance due to differences in the driving global climate models and the RCMs themselves. Overall, REMO consistently outperforms ALARO in simulating temperature-related indices, and ALARO-0 provides more accurate simulations for precipitation-related indices, and the multimodel ensemble (MME) tends to outperform individual RCMs. Under the representative concentration pathway (RCP) scenarios of RCP2.6 and RCP8.5, the MME results indicate a clear warming trend across CA for all temperature-related indices, except for the diurnal temperature range, with annual temperatures projected to increase by 0.15 °C/10 yr and 0.53 °C/10 yr, respectively. Both scenarios exhibit similar spatial distributions in projected annual precipitation, characterized by peak increases of ∼0.2 mm per day in northern CA. The number of consecutive dry days is projected to slightly increase under RCP8.5, while it is expected to slightly decrease under RCP2.6. This study improves our understanding of the applicability of RCMs in CA and provides reliable projections of future climate change.</div><div>摘要</div><div>本文基于CORDEX-CA-II中的多区域气候模式 (RCMs) 对中亚未来气候变化进行预估分析. 结果表明, 所有RCM均能再现温度和降水的主要气候态分布及极端事件, 其中REMO在温度相关指标模拟方面表现更好, 而Alaro-0在降水相关指标方面更具优势, 且多模式集合平均 (MME) 结果优于单个RCM. 在RCP2.6和RCP8.5排放情景下, 除日较差外, 中亚地区的温度相关指标均呈现出一致的上升趋势, 而年均降水变化的空间分布也较为相似, 高纬度地区增幅最为显著. 此外, 在RCP8.5情景下, 连续干燥日数预计将略有增加, 而在RCP2.6情景下则略有减少.</div></div>","PeriodicalId":47210,"journal":{"name":"Atmospheric and Oceanic Science Letters","volume":"19 2","pages":"Article 100660"},"PeriodicalIF":3.2,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145986691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}