本期覆盖 2026-09-18 至 2026-09-25，共收录高置信度文章 17 篇，边缘相关 2 篇，待人工核实 0 篇。

本周亮点

亮点 1：Dual‐Pathway Influence of Submesoscale Processes on the Southern Ocean Meridional Overturning Circulation

期刊：GRL ｜ DOI：https://doi.org/10.1029/2026gl124264

English summary

This study uses high-resolution simulations (1/48° and 1/24°) to decompose the Southern Ocean meridional overturning circulation (MOC) into large-, meso-, and submesoscale components. It reveals a dual-pathway influence of submesoscale processes on the residual MOC, which was previously poorly understood. The findings challenge the traditional view that mesoscale eddies alone dominate eddy compensation and highlight the importance of submesoscale dynamics in shaping overturning circulation. This work significantly advances understanding of Southern Ocean dynamics and their role in global climate.

中文解读

该研究利用1/48°和1/24°高分辨率模拟，将南大洋经向翻转环流（MOC）分解为大尺度、中尺度和亚中尺度分量，揭示了亚中尺度过程对残余MOC的双路径影响。此前亚中尺度过程的作用认识不足，该发现挑战了中尺度涡主导涡补偿的传统观点，强调了亚中尺度动力在塑造翻转环流中的重要性。这项工作显著推进了对南大洋动力及其在全球气候中作用的理解。

亮点 2：New Constraint on Future Ocean Heat Uptake Revealed by Considering Model Spread of Radiative Forcing

期刊：GRL ｜ DOI：https://doi.org/10.1029/2026gl123530

English summary

This study quantifies the contribution of radiative forcing to intermodel spread in future ocean heat uptake using a new set of CMIP6 experiments that diagnose time-varying forcing in 11 models. It finds that historical spread is strongly affected by forcing, while future spread is dominated by model sensitivity, leading to a robust correlation between historical and future ocean heat uptake (0.8–0.9). This provides a new constraint on future ocean heat uptake projections, which is critical for climate change assessment. The work bridges radiative forcing and ocean heat uptake, with broad implications for climate modeling.

中文解读

该研究利用一套新的CMIP6实验（在11个模式中诊断时变辐射强迫），量化了辐射强迫对未来海洋热吸收模式间差异的贡献。研究发现历史时期的差异主要受辐射强迫影响，而未来预估的差异则由模式敏感性主导，从而历史与未来海洋热吸收之间呈现稳健的相关性（0.8–0.9）。这为未来海洋热吸收预估提供了新的约束，对气候变化评估至关重要。该工作连接了辐射强迫与海洋热吸收，对气候建模具有广泛意义。

文章详览

1. JPO — How topographically modulated flow regimes of the Kuroshio influence along-stream heterogeneous dynamics and energetic connectivity

Abstract

Abstract Using a validated, high-resolution simulation (CMOMS), we quantify the topographically-modulated dynamics and energetic paths of the Kuroshio to characterize its along-stream heterogeneous variability and connectivity. Based on a dynamically consistent 3D jet stream definition, our analysis reveals two dynamically distinct regimes governed by the degree of topographic constraint on the Kuroshio’s structure and variability. Regime 1 exhibits strong topographically-constrained acceleration east of the Philippines and Taiwan, in the East China Sea, and south of Japan. In Regime 1, steep continental slopes channel the flow, intensify velocity and shear, but suppress lateral migration. The high mean kinetic energy is sustained primarily by ageostrophic pressure work driven by topographically-induced nonlinear advection for realistic forced-dissipative boundary current dynamics. Regime 2 features weakly topographically-constrained separation and meandering, in Luzon Strait, northeast of Taiwan, and south of Kyushu, downstream of the acceleration zones. In Regime 2, the Kuroshio transitions into a barotropically unstable mode, driving a vigorous conversion to eddy kinetic energy via Reynolds stresses. The unified Kuroshio upstream–downstream energetic connectivity alternates between these two regimes. The acceleration in Regime 1 accumulates high potential vorticity while mechanically suppressing meander growth via intense topographic straining. Once this straining diminishes downstream in Regime 2, the accumulated high-shear state facilitates barotropic instability, concurrently amplifying multiscale transient motions, particularly meanders and mesoscale eddies. Ultimately, this study highlights the importance of finite-Rossby-number ageostrophic processes and shear-strain competition in dictating the spatial heterogeneity along the western boundary currents from a comprehensive energetic perspective.

中文摘要

摘要 利用一个经过验证的高分辨率模拟（CMOMS），我们量化了黑潮受地形调制的动力学及其能量路径，以刻画其沿程的非均匀变率与连通性。基于一个动力学一致的三维急流定义，我们的分析揭示了两个动力学上截然不同的区域，其由地形对黑潮结构及变率的约束程度所决定。区域1表现出在菲律宾以东和台湾以东、东海以及日本以南由地形强烈约束的加速。在区域1中，陡峭的大陆坡引导流动，增强流速与切变，但抑制侧向迁移。对于真实的强迫-耗散边界流动力学而言，高平均动能主要由地形诱导的非线性平流所驱动的非地转压力做功维持。区域2的特征是地形约束较弱的分离与蛇行，出现在吕宋海峡、台湾东北以及九州以南，即加速区的下游。在区域2中，黑潮转变为正压不稳定模态，通过雷诺应力驱动向涡动能的强烈转换。统一的黑潮上游-下游能量连通性在这两个区域之间交替。区域1中的加速积累了高位涡，同时通过强烈的地形应变机械性地抑制蛇行增长。一旦这种应变在下游区域2中减弱，所积累的高切变状态便促进正压不稳定，同时放大跨尺度瞬态运动，尤其是蛇行和中尺度涡。最终，本研究从综合能量学视角强调了有限罗斯贝数非地转过程以及切变-应变竞争在决定西边界流沿程空间非均匀性方面的重要性。

2. JPO — Seasonal Shift in the Dominant Pathway Energizing Mesoscale Eddies in the California Current

  • 作者：Jack F. Gazeley, Sarah T. Gille, Lia Siegelman, Alberto C. Naveira Garabato, Jackie May, Joseph D’Addezio, Shang‐Ping Xie
  • 发表日期：2026-09-22
  • DOI：https://doi.org/10.1175/jpo-d-26-0092.1

Abstract

Abstract Mesoscale eddies are the dominant reservoir of kinetic energy in the ocean, yet the mechanisms that generate and maintain them in eastern boundary current systems remain incompletely assessed. Here we use a 1-km resolution simulation of the California Current System (CCS) to diagnose and quantify the processes that supply kinetic energy to the mesoscale band. A pronounced seasonal transition is evident in surface vorticity, kinetic energy spectra, and mixed-layer depth. In winter and spring, the mixed layer deepens during periods of strong wind work. Once the forcing relaxes, the mixed layer restratifies, generating submesoscale eddies and filaments. These features merge and transfer energy upscale, supplying the mesoscale through an inverse cascade. These mixed-layer restratification events occur most frequently when the mixed layer is deep (∼50 m) and highly variable. In contrast, during summer when the mixed layer is shallow, a mixed-layer-averaged geostrophic kinetic energy budget indicates that wind work accelerates the surface layer of the ocean more efficiently. This is associated with enhanced kinetic energy transfer from scales larger than 100 km into the mesoscale. Together, these results indicate a seasonally varying balance between inverse and direct kinetic energy transfers in the CCS, implying that the annual cycle of upper-ocean stratification leads to a seasonal shift in the dominant pathway of mesoscale eddy generation.

中文摘要

摘要 中尺度涡旋是海洋中动能的主要储库，然而在东边界流系统中，其生成与维持机制仍未得到充分评估。本文利用加利福尼亚流系（CCS）的1 km分辨率模拟，诊断并量化了向中尺度频带供给动能的过程。在地表涡度、动能谱和混合层深度中，存在明显的季节性转变。在冬季和春季，混合层在强风做功期间加深。一旦强迫减弱，混合层重新层化，生成亚中尺度涡旋和丝状结构。这些特征发生合并并向上尺度传递能量，通过逆级串向中尺度供给能量。这些混合层重新层化事件在混合层较深（约50 m）且高度多变时最为频繁。相比之下，在夏季混合层较浅时，混合层平均的地转动能收支表明，风做功更有效地加速海洋表层。这与从大于100 km的尺度向中尺度增强的动能传递有关。综合而言，这些结果表明，在CCS中逆动能传递与直接动能传递之间存在随季节变化的平衡，意味着上层海洋层化的年循环导致了中尺度涡旋生成主导路径的季节性转变。

3. JC — AMOC Discrepancies across Reanalyses and Models Limit Dynamical Understanding

Abstract

Abstract The Atlantic meridional overturning circulation (AMOC) influences global climate, yet its multiscale variability and the processes governing it remain uncertain across models and observations. Using four ocean reanalyses and forced ocean–sea ice simulations from three model families [Energy Exascale Earth System Model Model for Prediction Across Scales (MPAS), Parallel Ocean Program (POP), and Nucleus for European Modelling of the Ocean (NEMO)], each run in both a coarse [low resolution (LR)] and a mesoscale-permitting or eddy-resolving [high resolution (HR)] configuration, we assess the consistency of their representation of AMOC strength, overturning freshwater transport, salt-advection feedback, and gyre circulation around 58°N, 26°N, and 34°S over the past 50–70 years. Across the three model families, two LR–HR pairs simulate a stronger mean overturning at higher resolution, while one shows weak sensitivity. Across reanalyses, larger overturning amplitudes coincide with higher nominal resolution, but these products differ also in forcing, model formulation, and assimilation scheme. At 26°N, a robust negative coupling between freshwater transport and AMOC strength emerges across datasets, consistent with the salt-advection feedback. This relationship is absent at 58°N and inconsistent across datasets at 34°S, suggesting that the linear coupling between overturning and freshwater transport breaks down outside the subtropical North Atlantic. Among gyre diagnostics, only the mean strength of the North Atlantic subtropical gyre measured by its barotropic streamfunction exhibits a coherent and significant positive linear relationship with mean AMOC strength across all products and resolutions. No analogous signal emerges for the subpolar gyre or the South Atlantic subtropical gyre. This robustness points to the North Atlantic subtropical gyre as a consistent indicator of mean overturning strength across model strategies.

中文摘要

摘要 大西洋经向翻转环流（AMOC）影响全球气候，但其多尺度变率及其控制过程在模式与观测之间仍存在不确定性。利用四套海洋再分析资料以及来自三个模式族[能源百亿亿次地球系统模式（Energy Exascale Earth System Model）的跨尺度预测模式（Model for Prediction Across Scales，MPAS）、并行海洋计划（Parallel Ocean Program，POP）和欧洲海洋建模核心（Nucleus for European Modelling of the Ocean，NEMO）]的强迫海洋–海冰模拟，每个模式族均分别以粗分辨率[低分辨率（LR）]和中尺度可分辨或涡分辨[高分辨率（HR）]两种配置运行，我们评估了它们在过去50–70年间对AMOC强度、翻转淡水输运、盐平流反馈以及58°N、26°N和34°S附近环流涡旋的表征一致性。在三个模式族中，两对LR–HR配置在高分辨率下模拟出更强的平均翻转，而另一对则表现出较弱的敏感性。在各再分析资料之间，较大的翻转振幅与较高的名义分辨率相一致，但这些产品在强迫场、模式公式和同化方案方面也存在差异。在26°N，各数据集之间一致呈现出淡水输运与AMOC强度之间稳健的负耦合，这与盐平流反馈相一致。这种关系在58°N不存在，而在34°S各数据集之间不一致，表明翻转与淡水输运之间的线性耦合在副热带北大西洋以外区域失效。在环流涡旋诊断量中，只有以正压流函数衡量的北大西洋副热带涡旋平均强度，在所有产品和分辨率下均与平均AMOC强度呈现一致且显著的正线性关系。对于副极地涡旋或南大西洋副热带涡旋，则未出现类似信号。这种稳健性表明，北大西洋副热带涡旋可作为跨模式策略下平均翻转强度的一致指示量。

4. JC — Seasonal Linkages Between the MJO and Dominant Extratropical Modes Through Rossby Wave Source

Abstract

Abstract The Madden Julian Oscillation (MJO) is a tropical, intraseasonal phenomenon that generates teleconnections like the Pacific North American pattern in boreal winter, but knowledge about MJO teleconnections in other seasons is limited. To expand the knowledge of MJO teleconnections in all seasons, we investigate whether the MJO is tied to any leading extratropical modes in the Northern Hemisphere Pacific basin using reanalysis and satellite data. We demonstrate the strong seasonal variability of MJO teleconnections in the Northern Hemisphere Pacific basin at 200 hPa and the MJO is most strongly tied to the leading intraseasonal extratropical modes of variability over this region in December-January-February (DJF). However, the MJO has weaker relationships with the leading intraseasonal extratropical modes in other seasons. Our results suggest that the strength of the relationship between the MJO and intraseasonal extratropical modes can be explained partly by the strength of MJO-generated RWS and its similarity with RWS associated with the extratropical mode. The MJO-related RWS has strong seasonality due to the seasonality in the subtropical jet location and the strength of the MJO, but the seasonal MJO state has a greater impact than the seasonal state of the subtropical jet on producing the observed RWS pattern. This study suggests that improving the simulation of MJO seasonal convective behavior and associated upper-tropospheric divergence would have impact on improving its simulated teleconnection. Our presented results indicate the usefulness of the MJO as a predictability source in seasons beyond DJF may require finding meteorological or climate conditions that allow stronger MJO influence on the extratropics.

中文摘要

摘要 马登-朱利安振荡（MJO）是一种热带季节内现象，在 boreal winter 可生成如 Pacific North American pattern 之类的遥相关，但关于其他季节 MJO 遥相关的认识仍然有限。为拓展对全季节 MJO 遥相关的认识，我们利用再分析资料和卫星资料，研究 MJO 是否与北半球太平洋海盆任何领先的温带模态相联系。我们证明了北半球太平洋海盆 200 hPa 上 MJO 遥相关具有强烈的季节变率，且 MJO 在该区域于 December-January-February（DJF）与领先的季节内温带变率模态联系最强。然而，在其他季节，MJO 与领先的季节内温带模态的关系较弱。我们的结果表明，MJO 与季节内温带模态之间关系的强度，部分可由 MJO 生成的 RWS 的强度及其与温带模态相关 RWS 的相似性来解释。与 MJO 相关的 RWS 具有强烈的季节性，这是由于副热带急流位置的季节性和 MJO 的强度所致，但季节性的 MJO 状态对产生观测到的 RWS 型的影响大于副热带急流的季节性状态。本研究表明，改进对 MJO 季节对流行为及相关对流层上层辐散的模拟，将有助于改进其模拟的遥相关。我们给出的结果表明，要使 MJO 在 DJF 之外的季节成为有用可预报性来源，可能需要寻找允许 MJO 对温带产生更强影响的气象或气候条件。

5. JC — Interdecadal changes of the ENSO-induced summertime anomalous western North Pacific anticyclone

Abstract

Abstract El Niño–Southern Oscillation (ENSO) events which usually mature during winter can have significant impacts on subsequent summertime western North Pacific anticyclone (WNPAC) and associated East Asian rainfall. Such delayed impacts are known to undergo interdecadal changes, but a systematic investigation on the characteristics of these interdecadal changes and underlying mechanisms remains lacking. Using empirical orthogonal function (EOF) analysis on the 21-yr running regressions of subsequent summertime 850 hPa wind anomalies over the western North Pacific upon wintertime ENSO index for 1950–2024, we find two dominant modes of interdecadal changes in ENSO-induced summertime anomalous WNPAC. The first mode reflects interdecadal changes in intensity of the anomalous WNPAC which are linked to changes in ENSO-induced summertime sea surface temperature (SST) anomalies in the tropical Indian Ocean (TIO) through the TIO capacitor effect. The second mode represents interdecadal zonal displacements of the anomalous WNPAC which are associated with changes in ENSO-induced summertime SST anomalies around the Maritime Continent. After the 1990s, El Niño events tend to cause stronger summertime warm SST anomalies in the region which intensify local convection and Hadley cell, shifting the anomalous WNPAC westward to the South China Sea. Linear baroclinic model experiments support these results and indicate that the identified interdecadal changes can be largely explained by atmospheric responses to changes in ENSO-related tropical diabatic heating anomalies. Our results suggest that interdecadal changes in ENSO-induced summertime anomalous WNPAC arise from two distinct tropical SST teleconnection pathways, providing new insights into ENSO impacts under a changing climate.

中文摘要

摘要 通常在冬季成熟的厄尔尼诺-南方涛动（ENSO）事件可对随后夏季的西太平洋副热带高压（WNPAC）及相关的东亚降水产生显著影响。此类滞后影响已知会发生年代际变化，但对其年代际变化特征及潜在机制的系统性研究仍然缺乏。利用经验正交函数（EOF）分析，对1950-2024年冬季ENSO指数与随后夏季西太平洋850 hPa风异常的21年滑动回归进行分解，我们发现ENSO引起的夏季异常WNPAC年代际变化存在两个主导模态。第一模态反映了异常WNPAC强度的年代际变化，其与ENSO引起的夏季热带印度洋（TIO）海表温度（SST）异常变化通过TIO电容器效应相联系。第二模态代表了异常WNPAC的年代际纬向位移，其与ENSO引起的夏季海洋性大陆周边SST异常变化相关联。1990年代之后，厄尔尼诺事件倾向于在该区域引起更强的夏季暖SST异常，增强局地对流和哈得来环流，使异常WNPAC向西移动至南海。线性斜压模式试验支持了上述结果，并表明所识别的年代际变化在很大程度上可由大气对ENSO相关热带非绝热加热异常变化的响应来解释。我们的结果表明，ENSO引起的夏季异常WNPAC年代际变化源于两条不同的热带SST遥相关路径，为气候变化背景下ENSO的影响提供了新的认识。

6. JC — How regional SST shapes Saharan Near-Surface Temperature: Sensitivity and Dynamical Mechanisms

Abstract

Abstract The Sahara Desert has undergone substantial near-surface warming during the boreal warm season (June–November) in recent decades. Previous studies have suggested that historical and future Saharan warming is largely controlled by sea surface temperature (SST) changes. Here, we assess the sensitivity of Saharan near-surface temperature during the boreal warm season to SST anomalies at individual ocean grid points using Geophysical Fluid Dynamics Laboratory (GFDL) SST-patch experiments. To test the robustness of the results, we further validate the GFDL SST-patch responses using the Community Earth System Model (CESM). Both models consistently show that Saharan near-surface temperature is particularly sensitive to SST anomalies over the Mediterranean Sea, Caribbean Sea, and north Indian Ocean. Warming in the Mediterranean Sea and Caribbean Sea enhances Saharan warming, whereas warming in the north Indian Ocean induces Saharan cooling. The mechanisms underlying these responses are further examined using transient simulations and a potential temperature budget analysis. Results show that anomalous horizontal heat advection dominates the Saharan near-surface temperature response to SST perturbations, regardless of forcing location. Specifically, warming in the Mediterranean Sea and Caribbean Sea induces anomalous warm air advection over the Sahara accompanied by large-scale Rossby wave responses, whereas warming in the north Indian Ocean produces anomalous cold air advection associated with a Gill-type response and an intensified Azores High. These results demonstrate a strong basin dependence of SST impacts on Saharan temperature and underscore the dominant role of atmospheric circulation–driven horizontal heat advection in mediating the Saharan temperature response.

中文摘要

摘要 近几十年来，撒哈拉沙漠在北极暖季（6月至11月）经历了显著的地表附近增温。以往研究表明，历史和未来的撒哈拉增温在很大程度上受海表温度（SST）变化控制。本文利用地球物理流体动力学实验室（GFDL）SST斑块试验，评估了北极暖季期间撒哈拉地表附近温度对各个海洋网格点SST异常的敏感性。为检验结果的稳健性，我们进一步利用社区地球系统模式（CESM）验证了GFDL SST斑块响应。两个模式一致表明，撒哈拉地表附近温度对地中海、加勒比海和北印度洋的SST异常尤为敏感。地中海和加勒比海的增温增强撒哈拉增温，而北印度洋的增温则引起撒哈拉降温。我们进一步利用瞬变模拟和位温收支分析考察了这些响应背后的机制。结果表明，无论强迫位置如何，异常水平热平流均主导撒哈拉地表附近温度对SST扰动的响应。具体而言，地中海和加勒比海的增温在撒哈拉上空引起异常暖空气平流，并伴随大尺度罗斯贝波响应；而北印度洋的增温则产生异常冷空气平流，与Gill型响应及增强的亚速尔高压相关联。这些结果表明，SST对撒哈拉温度的影响具有强烈的海盆依赖性，并凸显了大气环流驱动的水平热平流在调节撒哈拉温度响应中的主导作用。

7. JC — Linkage between Northeast Pacific warm blob and following El Niño: Pivotal role of North Pacific meridional mode

Abstract

Abstract Anomalous upper-ocean warming spanning several thousand kilometers and persisting across seasons in the Northeast Pacific (NEP), known as the “warm blob”, has significant ecological and climatic impacts. Previous studies have suggested the statistical linkage between the warm blobs in preceding winter and the El Niño in subsequent winter, however, the involving physical mechanisms remain unclear. Our results show that some warm blobs induce a transition from a high-pressure system to a quasi-barotropic low-pressure system over the NEP in boreal winter through local ocean-atmosphere interaction: diabatic heating and transient eddy forcing jointly promote the low-pressure system in the lower troposphere, while transient eddy vorticity forcing contributes substantially to its upper-tropospheric structure. Such mid-latitude low-pressure anomaly leads to the development of the North Pacific Meridional Mode in boreal spring, with southwesterly wind anomalies reducing oceanic turbulent heat loss over the subtropical NEP, which ultimately triggers the following El Niño. The potential pathway underlying the linkage between the warm blobs and El Niño is further evidenced by numerical experiments with a slab ocean model coupled to the Community Atmosphere Model version 5. Our results advance understanding on the physical connection between extratropical NEP variability and El Niño.

中文摘要

摘要：东北太平洋（NEP）海表异常增暖可跨越数千公里并在多个季节持续存在，被称为“暖斑”，对生态和气候具有重要影响。已有研究表明，前冬暖斑与随后冬季厄尔尼诺之间存在统计联系，但其中涉及的物理机制仍不清楚。我们的结果表明，部分暖斑通过局地海气相互作用，在北方冬季诱导NEP上空由高压系统向准正压低压系统转变：非绝热加热与瞬变涡旋强迫共同促进了对流层低层低压系统的发展，而瞬变涡旋涡度强迫对其对流层上层结构有重要贡献。这种中纬度低压异常导致北方春季北太平洋经向模的发展，西南风异常减少了副热带NEP上空的海洋湍流热损失，最终触发随后的厄尔尼诺。通过将平板海洋模式与Community Atmosphere Model version 5耦合进行的数值试验，进一步证实了暖斑与厄尔尼诺之间联系的可能路径。我们的结果增进了对NEP温带变率与厄尔尼诺之间物理联系的理解。

8. JC — Physical processes to cause the seasonal change of the sea surface temperature in the equatorial Atlantic

Abstract

Abstract The physical mechanisms governing the seasonal cycle of sea surface temperature (SST) in the equatorial Atlantic are investigated, with particular emphasis on the rapid cooling period from April to July. Using mixed layer and subsurface heat budget analyses based on reanalysis data, we identify pronounced zonal contrasts in the dominant processes controlling SST variability. In the western region, surface heat fluxes, including the solar radiation flux (SRF) and latent heat flux (LHF), dominate the seasonal cycle of SST. In contrast, in the eastern region, the vertical diffusion at the base of the mixed layer contributes comparably to the LHF. The seasonal modulation of these processes is strongly influenced by the mixed layer depth (MLD) variations, which alter the mixed layer heat capacity and regulated the response of SST to surface forcing and subsurface heat exchange. In the eastern region, the enhanced vertical diffusion is linked to both MLD variation and changes in the vertical temperature gradient at the bottom of the mixed layer. Subsurface cooling begins earlier than surface cooling and is primarily associated with upwelling below the mixed layer. This subsurface cooling strengthens the vertical temperature gradient and provides an additional contribution to the enhanced vertical diffusion during the cooing period. These results demonstrate how the seasonally evolving mixed layer and subsurface jointly shape the asymmetric seasonal cycle of SST in the equatorial Atlantic.

中文摘要

摘要 本文研究了赤道大西洋海表温度（SST）季节循环的物理机制，重点关注4月至7月的快速降温期。基于再分析数据的混合层和次表层热收支分析，我们识别出控制SST变率的主导过程存在显著的东西向差异。在西部区域，表面热通量，包括太阳辐射通量（SRF）和潜热通量（LHF），主导了SST的季节循环。相比之下，在东部区域，混合层底部的垂直扩散与LHF的贡献相当。这些过程的季节调制受到混合层深度（MLD）变化的强烈影响，MLD变化改变了混合层热容量，并调控了SST对表面强迫和次表层热交换的响应。在东部区域，增强的垂直扩散与MLD变化以及混合层底部垂直温度梯度的变化均有关联。次表层降温开始于表面降温之前，主要与混合层以下的上升流有关。这种次表层降温增强了垂直温度梯度，并在降温期间对增强的垂直扩散提供了额外贡献。这些结果表明，季节演变的混合层和次表层如何共同塑造了赤道大西洋SST的非对称季节循环。

9. GRL — Observational Constraints on Sea Salt Contribution to CCN Over the Southern Ocean

  • 作者：Wei Xu, Hyo Jin Kang, Keran Zhang, Yang Lin, Ahsan Ali, Minju Seo, Yeontae Gim, Changeun Kim, Eunho Jang, Chang Hoon Jung, Ji Yi Lee, Radovan Krejčí, Ruqian Miao, Ji‐Yeon Park, Colin O’Dowd, Young Jun Yoon, Darius Čeburnis
  • 发表日期：2026-09-24
  • DOI：https://doi.org/10.1029/2026gl125204

Abstract

Abstract Earth system models exhibit persistent biases in simulating cloud condensation nuclei (CCN) over the Southern Ocean and Antarctica, largely due to inadequate representation of aerosol sources. Here, we present year‐round (January 2023–February 2024) measurements of aerosol hygroscopicity (HTDMA), particle number size distribution (SMPS), and CCN concentration from King Sejong Station (KSJ), Antarctica, to constrain CCN sources in this pristine environment. Size‐resolved hygroscopicity‐based source apportionment shows that sea salt aerosol (SSA) contributes 43%–54% of CCN at cloud‐relevant supersaturations (Sc = 0.2%–1.0%). Compared against the Copernicus Atmosphere Monitoring Service reanalysis (CAMSRA), our observations demonstrate that models underestimate SSA‐derived CCN at KSJ by a factor of 30 at Sc = 0.2%, providing critical constraints for aerosol–cloud interactions.

中文摘要

摘要 地球系统模式在模拟南大洋和南极洲上空的云凝结核（CCN）时存在持续性偏差，这主要归因于对气溶胶来源的刻画不足。本文介绍了来自南极洲King Sejong站（KSJ）的全年（2023年1月至2024年2月）气溶胶吸湿性（HTDMA）、粒子数谱分布（SMPS）和CCN浓度观测，以约束这一洁净环境中的CCN来源。基于粒径分辨吸湿性的来源解析表明，在云相关过饱和度（Sc = 0.2%–1.0%）下，海盐气溶胶（SSA）对CCN的贡献为43%–54%。与哥白尼大气监测服务再分析（CAMSRA）相比，我们的观测表明，模式在Sc = 0.2%时低估了KSJ由SSA产生的CCN达30倍，为气溶胶–云相互作用提供了关键约束。

10. GRL — Transition to Double‐Cell Mock Walker Circulations With Surface Warming Explained by Periodic Convection

Abstract

Abstract Idealized mock Walker simulations are widely used to study the interactions between overturning circulation and convection in the tropics. Previous studies documented a transition from a single‐cell to a double‐cell mock Walker circulation when the average sea surface temperature exceeds 300 K. Here, we ascribe the transition to the emergence of periodic convection with warming due to stronger convectively coupled waves. In cold simulations, the warm pool is dominated by steady deep convection, which results in a single overturning cell. In hot simulations, the warm pool is alternately dominated by deep convection and a stratiform mode, resulting in lower and upper cells respectively. This study suggests that the idealized mock Walker circulation in a warmer climate features complex structural changes in addition to a weakening in strength, and highlights the profound impacts of convection on the structure of the overturning circulation.

中文摘要

摘要 理想化模拟Walker环流被广泛用于研究热带地区翻转环流与对流之间的相互作用。以往研究记录了当平均海表温度超过300 K时，模拟Walker环流从单细胞向双细胞结构的转变。本文将这一转变归因于随增暖而出现的周期性对流，其由更强的对流耦合波所致。在冷态模拟中，暖池以稳定的深对流为主，从而形成单一的翻转细胞。在热态模拟中，暖池交替地由深对流和层状云模态主导，分别形成下层和上层细胞。本研究表明，在更暖气候下，理想化模拟Walker环流除强度减弱外，还表现出复杂的结构变化，并凸显了对流对翻转环流结构的深刻影响。

11. GRL — What Is the Observed Sensitivity of Arctic Sea Ice?

Abstract

Abstract The observed sensitivity of the Arctic summer sea‐ice area (SIA) to changes in the external forcing is a key quantity for understanding and projecting sea‐ice loss. Here, we estimate this sensitivity and provide a robust analysis of its uncertainty considering the impacts of internal variability, the memory of the system and observational uncertainty. We do so by developing and using a novel linear autoregressive AR(1) emulator. We find an observed sensitivity of 2.3 ± 0.5 m 2 SIA loss per ton of anthropogenic CO 2 emissions, and of 3.3 ± 1 million km 2 per °C of global warming, offering an independent benchmark for climate models. By extrapolating the emulator’s projections into the future, we confirm that the Arctic Ocean will become ice free in summer for the first time within the next few decades, namely for an additional 350 to 1,150 Gt of anthropogenic CO 2 emissions after 2025.

中文摘要

摘要 观测到的北极夏季海冰面积（SIA）对外部强迫变化的敏感性，是理解与预估海冰损失的关键量。本文估算了该敏感性，并在考虑内部变率、系统记忆及观测不确定性影响的基础上，对其不确定性进行了稳健分析。为此，我们开发并使用了一种新型线性自回归AR(1)仿真器。我们发现，观测到的敏感性为每吨人为CO₂排放导致2.3 ± 0.5 m²的SIA损失，以及全球变暖每升高1°C导致3.3 ± 1百万km²的SIA损失，为气候模式提供了独立基准。通过将仿真器的预估外推至未来，我们确认北冰洋将在未来数十年内首次出现夏季无冰，即在2025年之后，还需额外350至1,150 Gt的人为CO₂排放。

12. GRL — Dual‐Pathway Influence of Submesoscale Processes on the Southern Ocean Meridional Overturning Circulation

Abstract

Abstract The Southern Ocean meridional overturning circulation (MOC) play a crucial role in the global ocean water mass and heat redistribution, greatly modulating the earth climate variation. Although mesoscale eddies are known as an important component of the residual‐mean MOC that typically oppose wind‐driven Eulerian overturning, the contribution of submesoscale processes remains poorly understood. Based on high‐resolution simulations (1/48° and 1/24°), we decompose the residual MOC streamfunction into large‐, meso‐, and submesoscale components and reveal dual‐pathway impact of submesoscale processes. Specifically, the directly resolved submesoscale transport accounts for 18%–22% of the mesoscale anticlockwise overturning, and the amplification of mesoscale transport via submesoscale inverse energy cascade indirectly generates an additional enhancement of 24%–28%. Such a dual‐pathway impact, which is not resolved by climate models, exerts a substantial modification on the residual‐mean MOC, indicating that submesoscale dynamics are critical to the Southern Ocean MOC and call for reasonable parameterization in the future.

中文摘要

摘要 南大洋经向翻转环流（MOC）在全球海洋水团与热量再分配中起着至关重要的作用，极大地调控着地球气候变异。尽管中尺度涡旋已被认为是残余平均MOC的重要组成部分，且通常与风驱动的欧拉翻转相反，但次中尺度过程的贡献仍知之甚少。基于高分辨率模拟（1/48°和1/24°），我们将残余MOC流函数分解为大尺度、中尺度和次中尺度分量，揭示了次中尺度过程的双路径影响。具体而言，直接解析的次中尺度输运占中尺度逆时针翻转的18%–22%，而通过次中尺度逆能量级串对中尺度输运的放大则间接产生了24%–28%的额外增强。这种双路径影响无法被气候模式所解析，对残余平均MOC产生了显著调制，表明次中尺度动力学对南大洋MOC至关重要，并呼吁未来进行合理的参数化。

13. GRL — Co‐Occurring Weather Systems Vary by Atmospheric River Scale Across the United States

  • 作者：Diya Kamnani, Travis Allen O’Brien, Wei-Ming Tsai, Kwesi Twentwewa Quagraine, J. David Neelin, Jennifer L. Catto, Yang Zhou, Lai-Yung Ruby Leung, William R. Boos, Hongsheng Wang
  • 发表日期：2026-09-18
  • DOI：https://doi.org/10.1029/2026gl123975

Abstract

Abstract Atmospheric Rivers (ARs) often co‐occur with other weather systems, including fronts, low‐pressure systems (LPSs), and mesoscale convective systems (MCSs), which can amplify precipitation and flood risk. While extreme rainfall is frequently linked to multiple interacting features, how these systems co‐occur with AR intensity scales and regions remains unclear. Using ERA5‐derived feature masks and satellite data, we quantify spatiotemporal overlaps between ARs and other systems. AR + Front combinations dominate across much of the conterminous U.S. In higher AR scales (4–5), more complex MCS‐related combinations become increasingly common, particularly in DJF and MAM and along the West Coast, while limited LPS‐related co‐occurrences appear mainly in JJA and SON and are confined to regions such as the Gulf of Mexico and offshore Pacific genesis regions. In contrast, AR‐only occurrences dominate in some inland western regions. Extreme precipitation exhibits seasonal variation, with distinct co‐occurring systems contributing across seasons.

中文摘要

摘要 大气河（ARs）常与其他天气系统共同出现，包括锋面、低压系统（LPSs）和中尺度对流系统（MCSs），这些系统可放大降水与洪水风险。尽管极端降雨频繁地与多个相互作用特征相关联，但这些系统如何与AR强度等级及区域共同出现仍不明确。利用ERA5衍生的特征掩膜和卫星数据，我们量化了ARs与其他系统之间的时空重叠。AR+锋面组合在美国本土大部分地区占主导地位。在较高AR等级（4–5级）中，更复杂的与MCS相关的组合日益常见，尤其是在DJF和MAM期间以及沿西海岸地区，而有限的与LPS相关的共同出现主要出现在JJA和SON期间，且局限于墨西哥湾和近海太平洋生成区等区域。相比之下，仅AR出现的情况在部分西部内陆地区占主导地位。极端降水呈现季节性变化，不同季节由不同的共同出现系统作出贡献。

14. GRL — Decreasing Translation Speed of Rapid Expansion Tropical Cyclones Over the Western North Pacific

Abstract

Abstract The overall destructiveness of tropical cyclones (TCs) depends not only on their intensity but also on storm size and translation speed, which together determine the spatial extent and duration of impacts. However, variations in translation speed of TCs undergoing rapid expansion (RE) over recent decades remain poorly understood. Using multiple TC best‐track observations and reanalysis products, we revealed a significant decline in the translation speed of RE TCs over the western North Pacific during 1980–2024. This decline is driven by a shift in RE occurrence toward slower‐moving TCs. Composite analysis indicated that decreased mid‐level relative humidity gradient, weakened low‐level radial inflow, and reduced relative sea surface temperature (SST) surrounding faster‐moving TCs are primarily responsible for this shift. By linearly removing the effects of climate variability and long‐term SST trend, we further demonstrated that the slowdown of RE TCs is influenced by both Pacific decadal oscillation and global warming.

中文摘要

摘要 热带气旋（TC）的整体破坏性不仅取决于其强度，还取决于风暴尺度和移动速度，二者共同决定了影响的空间范围与持续时间。然而，近几十年来经历快速扩张（RE）的热带气旋移动速度变化仍认识不足。利用多套热带气旋最佳路径观测资料和再分析产品，我们揭示了1980—2024年间西北太平洋RE热带气旋移动速度的显著下降。这一下降由RE发生向移动较慢的热带气旋偏移所驱动。合成分析表明，中层相对湿度梯度减小、低层径向入流减弱以及移动较快热带气旋周围相对海表温度（SST）降低，是导致这一偏移的主要原因。通过线性去除气候变率与长期SST趋势的影响，我们进一步证明RE热带气旋的减速受到太平洋年代际振荡和全球变暖的共同影响。

15. GRL — Simulation of Coastal El Niño Events in CMIP6 Models and Its Relationship to Mean‐State and ENSO Biases

Abstract

Abstract Coastal El Niño (COA) events follow two evolution pathways, remaining in the far eastern Pacific or expanding into basin‐wide El Niño events. Analyzing 55 CMIP6 models, we show that the two pathways are associated with distinct central and eastern Pacific ocean‐atmosphere conditions, and the simulated frequency of each type is linked to tropical Pacific mean‐state biases (zonal for standalone, meridional for spreading) while inversely related to ENSO simulation skill. Only 16% of models reproduce observed COA frequency. Models overproducing COA events do so because of mean‐state biases that make coastal warming too easy to trigger, amplified by an overly sensitive local atmospheric response. Spreading events are systematically under‐produced, but their occurrence increases in models with more realistic meridional precipitation structure and, among the better‐performing models, more efficient wind‐thermocline coupling. These findings identify physical constraints governing COA evolution and the key model biases limiting the fidelity of COA simulation in CMIP6.

中文摘要

摘要 沿海厄尔尼诺（COA）事件遵循两种演变路径：或滞留于远东太平洋，或扩展为全海盆尺度的厄尔尼诺事件。通过分析55个CMIP6模式，我们表明这两种路径与中、东太平洋不同的海洋-大气条件相关联，且每种类型的模拟频率与热带太平洋平均态偏差有关（经向偏差对应独立型，经向偏差对应扩展型），同时与ENSO模拟技巧呈反相关。仅有16%的模式能够再现观测到的COA频率。过度产生COA事件的模式之所以如此，是因为平均态偏差使沿海增暖过于容易被触发，并因局地大气响应过于敏感而被放大。扩展型事件被系统性地低估，但在经向降水结构更为真实以及（在表现较好的模式中）风-温跃层耦合更为有效的模式中，其发生率有所增加。这些发现揭示了控制COA演变的物理约束条件，以及限制CMIP6中COA模拟保真度的关键模式偏差。

16. GRL — North Sea Storm Surges Amplified by Oscillations Triggered by Preceding Storms

  • 作者：Joris Beemster, Rijk A. Landsmeer, Sander A. M. A. de Maat, Chris Weijenborg, Svenja Fischer, D.S. van Maren, Antonius J. F. Hoitink
  • 发表日期：2026-09-24
  • DOI：https://doi.org/10.1029/2026gl125098

Abstract

Abstract Storm surges are often treated as independent extremes, yet extratropical cyclones and associated coastal water‐level extremes frequently occur in clustered sequences. Although clustering can increase flood hazard by shortening recovery time, it remains unclear whether preceding storms amplify subsequent surges. We investigate this for the North Sea along the NW European Shelf using long‐term tide gauge records and idealized hydrodynamic modeling. Observations show a pronounced excess of surge events separated by 1–3 days; events occurring about 2 days after a preceding surge have median peak heights 17.5% (6.8 cm) higher than more isolated events. Sequential‐storm experiments reproduce this timing dependence. Amplification arises from lingering post‐surge basin oscillations that constructively interact with subsequent storms, while nonlinear tide–surge interactions modulate but do not remove the effect. Storm clustering can therefore influence not only the frequency, but also the magnitude, of extreme coastal water levels.

中文摘要

摘要 风暴增水常被视为独立的极端事件，然而温带气旋及与之相关的沿岸水位极端事件却频繁以成簇序列的形式出现。尽管成簇现象可通过缩短恢复时间而加剧洪水灾害，但前序风暴是否会放大后续增水仍不明确。本文利用长期验潮站记录和理想化水动力模拟，针对北海及欧洲西北陆架区域开展了研究。观测结果表明，间隔1至3天的增水事件显著偏多；在前一次增水发生后约2天出现的事件，其峰值水位中位数比更为孤立的事件高出17.5%（6.8 cm）。连续风暴试验再现了这种时间依赖性。放大的原因在于增水后残留的盆地震荡与后续风暴发生相长干涉，而非线性潮汐—增水相互作用虽对其起调制作用，但并未消除该效应。因此，风暴成簇不仅能够影响极端沿岸水位的频率，还能够影响其量级。

17. GRL — New Constraint on Future Ocean Heat Uptake Revealed by Considering Model Spread of Radiative Forcing

Abstract

Abstract Radiative forcing is the fundamental driver of ocean heat uptake ; however, its contribution to intermodel spread in has not been quantified. We address this gap by leveraging a new set of CMIP6 experiments that diagnoses time‐varying for the first time in 11 models. Among them, we find that intermodel spread in is strongly affected by in historical simulations, but by model sensitivity in future projections. As a result, the correlation between historical and future is highly uncertain (0.1–0.7), whereas the correlation between historical and future is much more robust (0.8–0.9). For the 11 models, we show that imposing observed to constrain future can narrow its likely range by at least 10%. Finally, we emphasize that formulating as opens up new avenues for future ocean heat uptake studies.

中文摘要

摘要 辐射强迫是海洋热吸收的根本驱动因素；然而，其对模式间差异的贡献尚未被量化。我们通过利用一组新的CMIP6实验来填补这一空白，这些实验首次在11个模式中诊断了随时间变化的辐射强迫。在这些模式中，我们发现历史模拟中的模式间差异强烈受到辐射强迫的影响，而未来预估中的模式间差异则主要受模式敏感性的影响。因此，历史与未来辐射强迫之间的相关性高度不确定（0.1–0.7），而历史与未来海洋热吸收之间的相关性则稳健得多（0.8–0.9）。对于这11个模式，我们表明，施加观测约束以约束未来预估，可以将其可能范围至少缩小10%。最后，我们强调，将辐射强迫表述为海洋热吸收的形式，为未来海洋热吸收研究开辟了新的途径。

边缘相关条目

命中物理海洋学关键词，但同时涉及其他学科领域，仅供参考。

  • JC — The extreme and long-lasting marine heatwave in the northeastern Bay of Bengal during 2020 summer（DOI: https://doi.org/10.1175/jcli-d-25-0684.1）
    • 命中: mixed layer, marine heatwave, downwelling
    • 排除: coral
  • GRL — Open Ocean Biogeochemical Impacts of Extreme Terrestrial Precipitation（DOI: https://doi.org/10.1029/2026gl122966）
    • 命中: boundary current, submesoscale, eddies, salinity, freshwater
    • 排除: phytoplankton