本期覆盖 2026-06-26 至 2026-07-03，共收录高置信度文章 39 篇，边缘相关 4 篇，待人工核实 5 篇。

本周亮点

亮点 1：Weak 21st‐Century AMOC Response to Greenland Meltwater in a Strongly Eddying Ocean Model

期刊：GRL ｜ DOI：https://doi.org/10.1029/2026gl122545

English summary

This study uses a strongly eddying (1/10°) ocean model to assess the impact of Greenland meltwater on the AMOC under SSP5-8.5 forcing until 2100. The meltwater-induced additional AMOC weakening is small (0.6 ± 0.2 Sv) compared to the total weakening, suggesting that mesoscale eddies may buffer the meltwater effect. This challenges previous assumptions from non-eddying models that meltwater significantly accelerates AMOC decline.

中文解读

该研究利用强涡分辨率（1/10°）海洋模式，评估了格陵兰融水对AMOC在SSP5-8.5强迫下至2100年的影响。融水导致的额外AMOC减弱很小（0.6 ± 0.2 Sv），远小于总减弱幅度，表明中尺度涡旋可能缓冲了融水效应。这挑战了此前非涡分辨率模式中融水会显著加速AMOC减弱的假设。

亮点 2：Propagating Internal‐Tide‐Induced Wave Stresses Resolve Discrepancies in Ocean Surface Tide Energetics

期刊：GRL ｜ DOI：https://doi.org/10.1029/2026gl123598

English summary

This paper demonstrates that explicitly representing wave stresses from propagating internal tides in a global tide model resolves long-standing discrepancies in ocean surface tide energetics. The wave stresses, which are out of phase with the tidal flow, substantially modify tidal amplitudes and energy budgets. This represents a major methodological advance in tidal modeling with implications for ocean mixing and climate.

中文解读

本文证明，在全球潮汐模式中显式表示传播内潮产生的波应力，解决了海洋表面潮汐能量学中长期存在的差异。这些波应力与潮汐流异相，显著改变了潮汐振幅和能量收支。这代表了潮汐建模的重大方法学突破，对海洋混合和气候研究具有重要意义。

文章详览

1. JPO — Shear-flow instability of wind-wave coupling: numerical solutions compared to observations

Abstract

Abstract This paper investigates wave growth rates and wave-coherent airflow by numerically solving the Rayleigh equation and comparing the numerical solutions to field data collected at the Air-Sea Interaction Tower located south of Martha’s Vineyard under high wind conditions. The numerical analysis considers 10-m wind speeds from 2 to 21 m s −1 and wavelengths from 0.1 cm to 200 m. Growth rates from the numerical solutions show reasonable agreement with a commonly used parameterization. For wavelengths shorter than the most unstable modes, surface pressure lags the wave crest by less than 90°, whereas for field-scale wavelengths (> 10 m), surface pressure lags the wave crest by 110°–160°. The phases are nearly independent of height, consistent with past field observations. The wave-coherent pressure profiles for each wavenumber resemble an exponential decay far from the surface, but decay less steeply within half a wavelength above the surface. For 10-m wind speed U 10 = 16–22 m s −1 and frequency f = 0.15–0.25 Hz, the comparison between the numerical solutions and observations at 7 and 10 m heights for wave-coherent pressure and vertical velocity shows reasonable agreement. Integrating momentum flux over all wavenumbers at each measurement height, we show that at a height of 1 m, the wave-driven momentum fluxes are on the order of 1% of the total turbulent flux.

中文摘要

摘要 本文通过数值求解瑞利方程，并将数值解与高风速条件下在玛莎葡萄园岛南部海气相互作用塔收集的现场数据进行对比，研究了波浪增长率及波浪相干气流。数值分析考虑了10米风速从2米/秒到21米/秒、波长从0.1厘米到200米的范围。数值解得到的增长率与常用参数化方案的结果具有合理的一致性。对于短于最不稳定模态波长的波浪，表面压力滞后于波峰的角度小于90°；而对于现场尺度波长（>10米），表面压力滞后于波峰的角度为110°–160°。相位几乎与高度无关，这与以往的现场观测结果一致。每个波数的波浪相干压力廓线在远离海面时呈指数衰减，但在海面上方半个波长范围内衰减较缓。当10米风速U10 = 16–22米/秒、频率f = 0.15–0.25赫兹时，数值解与7米和10米高度处波浪相干压力和垂直速度的观测结果具有合理的一致性。通过在每个测量高度对所有波数的动量通量进行积分，我们发现在1米高度处，波浪驱动的动量通量约为总湍流通量的1%。

2. JPO — Interannual Salinity Variability on the Ross Sea Continental Shelf in a Regional Ocean–Sea Ice–Ice Shelf Model. Part I: SurfaceDriven Processes

Abstract

Abstract The Ross Sea continental shelf plays a critical role in Antarctic Bottom Water formation through the production of High Salinity Shelf Water (HSSW), with implications for the global overturning circulation. The salinity of HSSW exhibits pronounced interannual variability, while its spatiotemporal characteristics and governing mechanisms remain poorly understood. Using a regional ocean–sea ice–ice shelf coupled model, we investigate the nature of this variability and the major driving processes. Here, in Part I, we focus on surface–driven processes, analyzing the factors governing surface salinity variability, including interannual changes in surface salt flux and the role of surface salt advection. Our results show that variability in surface salt flux is primarily driven by southwesterly winds anomalies over the continental shelf, which are influenced by the atmospheric circulation pattern across the Ross Sea. These wind anomalies control the net sea ice transport change across the shelf break, along with sea ice production mainly over the eastern continental shelf and within the Ross Ice Shelf Polynya. Advected westward by surface currents, salinity anomalies originating in the eastern continental shelf region thereby influence surface properties in the western Ross Ice Shelf Polynya and the Terra Nova Bay Polynya, the primary HSSW formation sites. Identifying these surface-driven mechanisms provides a foundation for assessing the contributions of internal oceanic processes to interannual salinity variability, which is investigated in Part II.

中文摘要

摘要 罗斯海大陆架通过生成高盐陆架水（HSSW）在南极底层水形成中发挥关键作用，进而影响全球翻转环流。HSSW的盐度表现出显著的年际变率，但其时空特征及控制机制仍鲜为人知。本文利用区域海洋-海冰-冰架耦合模式，探究了该变率的本质及主要驱动过程。在第一部分中，我们聚焦于海表驱动过程，分析了控制海表盐度变率的因素，包括海表盐通量的年际变化以及海表盐平流的作用。结果表明，海表盐通量的变率主要由大陆架上空的西南风异常驱动，而该风异常受罗斯海大气环流格局的影响。这些风异常控制了陆架坡折处的净海冰输送变化，以及主要发生在东部大陆架和罗斯冰架冰间湖区域的海冰生成。受表层海流向西平流输送，源自东部大陆架区域的盐度异常进而影响西部罗斯冰架冰间湖和特拉诺瓦湾冰间湖（HSSW的主要形成区域）的表层特性。识别这些海表驱动机制为评估内部海洋过程对盐度年际变率的贡献奠定了基础，相关研究将在第二部分中展开。

3. JGR: Oceans — Spreading of a Deep‐Ocean Tracer in a Suite of Eulerian and Lagrangian Simulations

  • 作者：M. Gabriela Escobar-Franco, Mathieu Huret, Clément Vic, Thomas Gorguès, Jonathan Gula, Cécile Cathalot
  • 发表日期：2026-06-27
  • DOI：https://doi.org/10.1029/2025jc023925

Abstract

Abstract Hydrothermal vents are important sources of biogeochemical constituents with a global relevance, like iron. The fate of these elements is poorly constrained, both by the physical mechanisms of transport and mixing, and by the geochemical speciation processes. Here we set up a regional simulation of the ocean circulation that resolves submesoscale and tidal processes around the Trans‐Atlantic Geotraverse (TAG) hydrothermal vent to investigate how the small scales of the dynamics impact the dispersal of a hydrothermal plume. A passive Eulerian tracer is continuously released at TAG and spreads over 260 days. We design sensitivity experiments to isolate key forcing mechanisms: a simulation without tides, a simulation with a bathymetry that is smoothed to remove kilometer‐scale features, and a simulation with Lagrangian particles to be compared to the Eulerian framework. We find that the kilometer‐scale seafloor topography is essential to drive submesoscale instabilities and generate submesoscale eddies that capture seafloor material and transport it off the ridge, increasing dramatically the horizontal spreading as compared to the smooth‐bathymetry simulation. Tides are found to increase vertical diffusivity above the ridge, but their impact on the horizontal dispersal is negligible. Eulerian and Lagrangian experiments lead to very similar horizontal dispersal pathways, although the vertical spreading is much reduced in the Lagrangian simulation, which is explained by the lack of an explicit representation of mixing processes.

中文摘要

摘要 热液喷口是铁等具有全球意义的生物地球化学组分的重要来源。这些元素的最终去向受物理输运与混合机制以及地球化学形态转化过程的共同制约，但目前对其认知仍十分有限。本研究围绕跨大西洋地学断面（TAG）热液喷口区域，构建了能够解析亚中尺度及潮汐过程的高分辨率海洋环流区域模拟，旨在探究小尺度动力学过程对热液羽流扩散的影响。通过连续释放被动欧拉示踪剂，模拟了TAG喷口羽流在260天内的扩散过程。我们设计了敏感性实验以分离关键强迫机制：包括无潮汐模拟、平滑去除千米级地形特征的模拟，以及采用拉格朗日粒子与欧拉框架对比的模拟。研究发现，千米级海底地形是驱动亚中尺度不稳定性的关键因素，其产生的亚中尺度涡旋能够捕获海底物质并将其输运至洋脊之外，相较于平滑地形模拟，水平扩散范围显著增大。潮汐作用虽能增强洋脊上方的垂向扩散系数，但对水平扩散的影响可忽略不计。欧拉与拉格朗日实验在水平扩散路径上高度一致，但拉格朗日模拟中垂向扩散范围显著减小，这归因于其缺乏混合过程的显式表征。

4. JGR: Oceans — Warm Surface Waters Dominate Melting of the Denman‐Shackleton Ice Shelf System

Abstract

Abstract The ocean dynamics controlling the melting of the Denman‐Shackleton ice shelf system are investigated using a high‐resolution regional ocean‐sea ice‐ice shelf model. Our results show that basal meltwater production exhibits strong seasonal variability, driven by the ocean heat supply toward the ice shelf system, and occurs through two distinct melting modes, “shallow” and “deep.” The vertical distribution of the basal meltwater production—and hence the relative contribution of the shallow and deep modes to melting—is modulated by the frequency distribution of ice shelf draft, with the largest ice‐ocean interface area occurring between 100 and 300 m depth. As a result, shallow melting dominates meltwater production in this region, peaking in January‐May when air‐sea fluxes warm sea ice‐free surface waters over the continental shelf. These warmed surface waters are subsequently transported shoreward by wind‐driven onshore Ekman transport, subduct beneath the ice front through downwelling, and become a heat source for shallow basal melting of the ice shelf. At the same time, this wind‐driven Ekman transport sets up the westward Antarctic Coastal Current along the coastal margin, delivering warm surface waters to the ice shelf from the east and thereby further contributing to shallow basal melting. Our results highlight the critical role of sea ice, wind, and air‐sea fluxes in driving basal melting in this region, and suggest that this basal melting is likely to intensify as Antarctic sea ice declines.

中文摘要

摘要 利用高分辨率区域海洋-海冰-冰架模型，研究了控制登曼-沙克尔顿冰架系统融化的海洋动力学过程。结果表明，基底融水产量表现出强烈的季节性变化，受海洋向冰架系统输送热量的驱动，并通过“浅层”和“深层”两种不同的融化模式发生。基底融水产量的垂直分布——即浅层和深层模式对融化的相对贡献——受冰架吃水深度的频率分布调制，其中冰-海洋界面面积最大的区域位于100至300米深度之间。因此，浅层融化主导了该区域的融水产量，在1月至5月达到峰值，此时海-气通量使陆架上海冰覆盖的表层海水变暖。这些变暖的表层海水随后通过风驱动的向岸埃克曼输送向岸移动，经下降流潜沉至冰架前缘下方，成为冰架浅层基底融化的热源。同时，这种风驱动的埃克曼输送沿海岸边缘形成了向西的南极沿岸流，将暖表层海水从东部输送到冰架，从而进一步促进了浅层基底融化。我们的结果强调了海冰、风和海-气通量在驱动该区域基底融化中的关键作用，并表明随着南极海冰减少，这种基底融化可能会加剧。

5. JPO — Reliability of a Theoretically Operable Method to Quantify TC-Induced Upwelling

Abstract

Abstract A theoretically operable but unvalidated method has been presented to observe the strength of the upwelling induced by global tropical cyclones (TCs); here, it is validated using observations from the daily 2-km-resolution level-3 Surface Water and Ocean Topography (SWOTl3) satellite data. The method quantifies the upwelling strength as the change of the sea surface height (SSH) extreme within a cyclonic ocean eddy (COE) or anticyclonic ocean eddy (AOE) identified from low-resolution gridded altimetry datasets. Although the artificial smoothness segment (ASS) always exists in the time series of an observed eddy SSH extreme, the method further argued that the maximum change in the ASS theoretically equals to the upwelling strength. To evidence its reliability, the time series of swath-mean SSH and the eddy extremes of three COEs and an AOE are derived from four gridded datasets. In sharp contrast to the abrupt decreases in SWOTl3-observed data, all the time series from the gridded datasets show the slow decrease near the typhoon’s passage and thus directly verify the existing ASSs. Using the method, the quantified upwelling strengths near 17°N are very consistent with the SWOTl3 observations, confirming its reliability. The quantified upwelling strengths in the Kuroshio near 27°N seem to be enhanced with the increasing quality of the gridded datasets. However, even in the Kuroshio, the upwelling strength quantified from the best available gridded dataset in recent years should still be reliable. The validated method will provide an effective tool to quantify global TC-induced upwelling. Significance Statement The upwelling induced by a tropical cyclone plays a key role in the effects of global tropical cyclones on ocean. However, a feasible method to quantify the upwelling strength is still absent for global tropical cyclones. A theoretically operable but unvalidated method has been presented. Here, this method is validated to be reliable using observations from the daily 2-km-resolution level-3 Surface Water and Ocean Topography satellite data.

中文摘要

摘要 一种理论上可行但尚未验证的方法已被提出，用于观测全球热带气旋（TCs）引起的上升流强度；本文利用每日2公里分辨率的三级地表水与海洋地形（SWOTl3）卫星数据对该方法进行了验证。该方法通过从低分辨率网格化高度计数据集中识别出的气旋式海洋涡旋（COE）或反气旋式海洋涡旋（AOE）的海面高度（SSH）极值变化来量化上升流强度。尽管观测到的涡旋SSH极值时间序列中始终存在人为平滑段（ASS），但该方法进一步论证了ASS的最大变化理论上等于上升流强度。为证明其可靠性，从四个网格化数据集中提取了三个COE和一个AOE的条带平均SSH及涡旋极值的时间序列。与SWOTl3观测数据中的急剧下降形成鲜明对比的是，所有网格化数据集的时间序列在台风过境附近均显示出缓慢下降，从而直接验证了现有ASS的存在。利用该方法，在17°N附近量化的上升流强度与SWOTl3观测结果高度一致，证实了其可靠性。在27°N附近的黑潮区域，量化的上升流强度似乎随网格化数据集质量的提高而增强。然而，即使在黑潮区域，近年来最佳可用网格化数据集量化的上升流强度仍应是可靠的。经过验证的方法将为量化全球热带气旋引起的上升流提供有效工具。意义声明 热带气旋引起的上升流在全球热带气旋对海洋的影响中起着关键作用。然而，目前仍缺乏一种可行的方法来量化全球热带气旋的上升流强度。一种理论上可行但尚未验证的方法已被提出。本文利用每日2公里分辨率的三级地表水与海洋地形卫星数据验证了该方法的可靠性。

6. JPO — Origin of the Antarctic Intermediate Water in the Southern Ocean Identified by a Distance Metric

Abstract

Abstract Antarctic Intermediate Water (AAIW), occupying a broad region at intermediate depths in the Southern Hemisphere oceans, plays a crucial role in global heat and freshwater redistribution. However, its origin at the sea surface remains a subject of ongoing debate. A recently defined distance metric, which distinguishes similar water parcels, is applied to Argo data to trace the surface origins of the AAIW cores in each ocean basin. By examining the spatial distribution of distances to the AAIW cores, we identify that the Pacific and Atlantic AAIW cores primarily originate from localized surface regions, specifically near the Subantarctic Front in the southeast Pacific and the Falkland Plateau in the southwest Atlantic. Further investigation indicates that through subduction in the deep mixed layer, low-salinity water penetrates to intermediate depths in these regions. North of the subduction sites, water masses primarily circulate within the subtropical gyre in the South Pacific, whereas to the south, they are advected eastward by the Antarctic Circumpolar Current into the Atlantic Ocean. In the Indian Ocean, the AAIW core, distinguished by its relatively low oxygen concentration, originates both from eastward inflow carried by the Antarctic Circumpolar Current from the southeast Pacific and local surface sources near 90°E. Our findings confirm the reliability of the distance metric and emphasize the importance of localized physical processes in the penetration of AAIW into the ocean interior. Significance Statement Antarctic Intermediate Water (AAIW), found in Southern Hemisphere intermediate depths, is essential for global heat and freshwater distribution. Using a newly defined distance metric, it is found that AAIW originates primarily from the Subantarctic Front in the southeast Pacific and the Falkland Plateau in the southwest Atlantic, where low-salinity water subducts into deeper layers. In contrast, the Indian Ocean lacks this direct path, with its AAIW formed by the inflow of AAIW from the Atlantic via the Antarctic Circumpolar Current. These findings improve our understanding of AAIW origins and pathways within the ocean.

中文摘要

摘要 南极中层水（AAIW）占据南半球海洋中层深度的大片区域，在全球热量和淡水再分配中发挥着关键作用。然而，其海表起源仍是持续争论的课题。一种新近定义的、用于区分相似水团的距离度量方法被应用于Argo数据，以追溯各海盆中AAIW核心的海表起源。通过分析距AAIW核心距离的空间分布，我们发现太平洋和大西洋的AAIW核心主要源自局地海表区域，具体而言是东南太平洋的亚南极锋和西南大西洋的福克兰海台附近。进一步研究表明，通过深混合层中的潜沉过程，低盐水在这些区域渗透至中层深度。在潜沉点以北，水团主要在南太平洋副热带环流内循环；而在潜沉点以南，水团则被南极绕极流向东输送进入大西洋。在印度洋，AAIW核心以其相对较低的氧浓度为特征，其来源既包括从东南太平洋经南极绕极流输入的东向流入水，也包括90°E附近的局地海表源。我们的发现证实了距离度量方法的可靠性，并强调了局地物理过程在AAIW向海洋内部渗透中的重要性。意义声明 南极中层水（AAIW）存在于南半球中层深度，对全球热量和淡水分布至关重要。利用新定义的距离度量方法，发现AAIW主要源自东南太平洋的亚南极锋和西南大西洋的福克兰海台，低盐水在此处潜沉至更深层。相比之下，印度洋缺乏这种直接路径，其AAIW由经南极绕极流从大西洋输入的AAIW形成。这些发现增进了我们对AAIW起源及海洋内路径的理解。

7. JPO — Propagation and Dissipation of Southern Ocean Swells: A CFOSAT SWIM–Based Analysis

Abstract

Abstract The physical mechanisms governing ocean swell propagation are long-standing issues in physical oceanography. One key aspect is the dissipation of swell energy across the oceans, which is constrained due to limitations in observational coverage. In this study, the trans-Pacific propagation and dissipation of swells generated by Southern Ocean storms are investigated. Data are sourced from the Chinese–French Oceanography Satellite ( CFOSAT ) Surface Waves Investigation and Monitoring (SWIM) instrument, buoy observations, wave hindcast, and reanalysis. A total of 1755 swell trajectories are traced to quantify spectral evolution, wavelength variation, and energy dissipation along great-circle paths. As swells propagate across the ocean, the spectral width and its distribution range narrow monotonically. This demonstrates the progressive separation of frequency components in space and time as a result of frequency dispersion, leading to a more monochromatic wave field locally. The mean dissipation rate is estimated at 2.09 ± 0.024 × 10 −7 m −1 , with an attenuation rate of 5.05 ± 0.027 × 10 −7 m −1 . This dissipation level is approximately twice that of previous studies and exhibits a systematic bias relative to the trackwise estimate (1.35 × 10 −7 m −1 ), likely reflecting the sensitivity of pointwise calculations to observational noise. Beyond 4000 km from the storm source, both spectral width and its variability narrow significantly. Additionally, the spectrally weighted peak wavelength within the swell partition increases by approximately 11 m (1000 km) −1 of propagation. Significance Statement Southern Ocean swells, which are long ocean surface waves generated by storms, can travel thousands of kilometers across the ocean and impact distant coastal regions due to their relatively low dissipation of energy. Using data from the Chinese–French Oceanography Satellite ( CFOSAT ) Surface Waves Investigation and Monitoring (SWIM) instrument, we tracked how these waves evolve over time and distance. It is found that as swells propagate away from the storm source, their energy decreases, and the energy becomes more monochromatic locally due to the separation of dispersion, as indicated by the narrower widths of the wave spectra. The dissipation rate is statistically quantified across a large number of swell trajectories, revealing systematic variations with distance, wave steepness, and significant wave height.

中文摘要

摘要 控制海洋涌浪传播的物理机制是物理海洋学中长期存在的问题。其中一个关键方面是涌浪能量在海洋中的耗散，由于观测覆盖范围的限制，这一过程受到约束。本研究调查了南大洋风暴产生的涌浪在横跨太平洋的传播与耗散过程。数据来源于中法海洋卫星（CFOSAT）表面波浪探测与监测（SWIM）仪器、浮标观测、波浪后报模拟及再分析资料。共追踪了1755条涌浪轨迹，以量化沿大圆路径的谱演化、波长变化及能量耗散。随着涌浪在海洋中传播，谱宽度及其分布范围单调变窄。这表明由于频散作用，频率成分在空间和时间上逐渐分离，导致局地波场趋于单色化。平均耗散率估计为2.09 ± 0.024 × 10⁻⁷ m⁻¹，衰减率为5.05 ± 0.027 × 10⁻⁷ m⁻¹。这一耗散水平约为先前研究的两倍，且相对于沿轨迹估计值（1.35 × 10⁻⁷ m⁻¹）存在系统性偏差，可能反映了点估计对观测噪声的敏感性。在距离风暴源超过4000公里处，谱宽度及其变异性均显著减小。此外，涌浪分区内的谱加权峰值波长以约11米每1000公里传播距离的速率增加。意义声明 南大洋涌浪是由风暴产生的长海洋表面波，由于其能量耗散相对较低，可跨越数千公里传播并影响遥远的海岸区域。利用中法海洋卫星（CFOSAT）表面波浪探测与监测（SWIM）仪器的数据，我们追踪了这些波浪随时间和距离的演化过程。研究发现，随着涌浪远离风暴源传播，其能量减少，且由于频散分离导致波谱宽度变窄，局地能量分布趋于单色化。基于大量涌浪轨迹的统计量化揭示了耗散率随距离、波陡及有效波高的系统性变化。

8. JPO — Waves Explain Observed Similarity Scaling of Turbulence Dissipation in the Southern Ocean

Abstract

Abstract We investigate the turbulence kinetic energy (TKE) budget of the upper ocean and its response to wind and wave forcing in the Southern Ocean, using realistically forced large-eddy simulations (LESs) and in situ microstructure shear observations. The widely used law of the wall similarity scaling assumes that shear production of TKE is balanced by its dissipation. However, our findings reiterate that this assumption is violated under wave forcing: Dissipation is primarily balanced by local Stokes shear production, augmented by almost equal contributions from local Eulerian shear production and nonlocal convergence of TKE transport. Despite this, the canonical law of the wall scaling reasonably describes the vertical distribution of dissipation rates in the boundary layer in both realistically forced LES and observations, even though the underlying physical reasoning does not hold. We propose a modified scaling to account for the nonlocal component of the TKE budget that yields accurate predictions of the TKE budget as well as an interpretation accounting for wave effects. These insights have important implications for interpreting turbulence dissipation rate observations. Significance Statement This study provides and evaluates a physical model of turbulence in the near-surface layer of the Southern Ocean under strong winds and waves. This turbulence model quantifies how the vertical transport and dissipation of turbulence relate to the production of turbulence due to winds and waves. This model of turbulence is valuable because the Southern Ocean plays a key role in regulating climate through the uptake of heat and carbon from the atmosphere, which is mediated by small-scale turbulent motions that generally must be estimated without turbulence observations in global ocean and climate simulations. In addition, this model provides insight into dissipation rate observations, which are generally collected without observations of the corresponding turbulence production and transport.

中文摘要

摘要 我们利用真实强迫的大涡模拟（LES）和现场微结构剪切观测，研究了南大洋上层海洋的湍流动能（TKE）收支及其对风浪强迫的响应。广泛使用的壁面律相似性标度假设TKE的剪切产生与其耗散相平衡。然而，我们的研究结果再次表明，在波浪强迫下这一假设不成立：耗散主要由局地斯托克斯剪切产生平衡，并辅以几乎等量的局地欧拉剪切产生和非局地TKE输运的辐合贡献。尽管如此，在真实强迫的LES和观测中，经典的壁面律标度仍能合理描述边界层内耗散率的垂向分布，尽管其背后的物理推理并不成立。我们提出了一种修正标度，以考虑TKE收支的非局地分量，该标度能准确预测TKE收支，并提供考虑波浪效应的物理解释。这些见解对解释湍流耗散率观测具有重要意义。意义声明 本研究提出并评估了强风浪条件下南大洋近表层湍流的物理模型。该湍流模型量化了湍流的垂向输运和耗散如何与风浪产生的湍流相关联。该湍流模型具有重要价值，因为南大洋通过吸收大气中的热量和碳在调节气候中发挥关键作用，而这一过程受小尺度湍流运动调控，在全球海洋和气候模拟中通常需在缺乏湍流观测的情况下进行估算。此外，该模型为耗散率观测提供了见解，这些观测通常在缺乏相应湍流产生和输运观测的情况下进行。

9. JPO — Submesoscale Thermohaline Compensation and Its Role in Frontogenesis

Abstract

Abstract Upper thermohaline properties play a critical role in mediating the transfer of momentum, heat, and biogeochemical tracers, thereby influencing the global carbon cycle and climate system. Thermohaline compensation—where temperature and salinity exert opposing effects on seawater density—is more prevalent in the mixed layer and modulates frontal dynamics. In this study, observations from 12 underwater gliders reveal that thermohaline compensation within salinity fronts becomes more pronounced at submesoscales during a tropical cyclone in the northern South China Sea. Comparative analyses from idealized numerical experiments demonstrate that surface cooling enhances submesoscale activity and thermohaline compensation at salinity fronts, with the compensated ratio reaching approximately 20%. Through intense submesoscale ageostrophic motions and restratification, surface cooling generates temperature perturbations to rapidly form temperature fronts aligned with salinity gradients, thereby enhancing submesoscale thermohaline compensation more effectively. Surface diabatic effects are incorporated into the frontogenesis function by accounting for surface cooling and submesoscale restratification. This process becomes more pronounced and efficient as submesoscale restratification shoals the mixed layer. Atmospheric cooling over submesoscale salinity fronts, together with the accompanying submesoscale compensation, constitutes a sink of oceanic eddy potential energy (EPE). These findings advance our understanding of thermohaline compensation mechanisms and the modulation of submesoscale frontal dynamics by atmospheric forcing, offering further insights into air–sea interactions in dynamically active, salinity-dominated ocean regimes. Significance Statement Upper-ocean fronts at submesoscales (a few kilometers) are dynamically active features of the global ocean that strongly influence air–sea exchange and the vertical redistribution of heat, momentum, and nutrients. Thermohaline compensation, arising from the opposing effects of temperature and salinity on seawater density, can weaken horizontal density gradients and thereby reduce frontal intensity. Using 12 glider-based observations and high-resolution idealized simulations, this study demonstrates that atmospheric cooling can induce thermohaline compensation and reshape submesoscale frontal structures. These findings highlight the need of joint air–sea observations for better investigating submesoscale frontal evolution. Improved understanding of fine-scale thermohaline coupling is essential for advancing upper-ocean frontal dynamics and clarifying the broader climatic and ecological roles of fronts.

中文摘要

摘要 上层温盐特性在动量、热量及生物地球化学示踪物的传递中起着关键作用，进而影响全球碳循环和气候系统。温盐补偿——即温度和盐度对海水密度产生相反效应——在混合层中更为普遍，并调节锋面动力学。本研究利用12台水下滑翔机的观测数据揭示，在中国南海北部的一次热带气旋期间，盐度锋面内的温盐补偿在亚中尺度上变得更加显著。来自理想化数值实验的比较分析表明，海面冷却增强了亚中尺度活动及盐度锋面的温盐补偿，补偿比率达到约20%。通过强烈的亚中尺度地转运动及再层化，海面冷却产生温度扰动，迅速形成与盐度梯度对齐的温度锋面，从而更有效地增强亚中尺度温盐补偿。通过考虑海面冷却和亚中尺度再层化，将海面非绝热效应纳入锋生函数。随着亚中尺度再层化使混合层变浅，这一过程变得更加显著和高效。亚中尺度盐度锋面上的大气冷却，连同伴随的亚中尺度补偿，构成了海洋涡旋有效势能（EPE）的汇。这些发现推进了我们对温盐补偿机制及大气强迫对亚中尺度锋面动力学调节的理解，为动态活跃、盐度主导的海洋区域中的海气相互作用提供了进一步见解。意义声明 亚中尺度（数公里）的上层海洋锋面是全球海洋中动态活跃的特征，强烈影响海气交换及热量、动量和营养盐的垂直再分布。温盐补偿源于温度和盐度对海水密度的相反效应，可削弱水平密度梯度，从而降低锋面强度。本研究利用12台滑翔机观测和高分辨率理想化模拟，证明大气冷却可诱发温盐补偿并重塑亚中尺度锋面结构。这些发现强调了联合海气观测对于更好研究亚中尺度锋面演化的必要性。对精细尺度温盐耦合的深入理解，对于推进上层海洋锋面动力学及阐明锋面更广泛的气候和生态作用至关重要。

10. JPO — Characteristics, Sources, and Energetics of Yanai Waves in the Equatorial Indian Ocean

  • 作者：Jinghong Wang, Peter Brandt, Rena Czeschel, Yeqiang Shu, Dongxiao Wang, Ju Chen, Yang Yang, Ke Huang, Yunkai He, Yilun Tian
  • 发表日期：2026-07-01
  • DOI：https://doi.org/10.1175/jpo-d-25-0156.1

Abstract

Abstract In the equatorial Indian Ocean, observations and the Global Ocean Reanalysis and Simulation (GLORYS) dataset reveal significant intraseasonal variability of meridional velocity in the upper 500 m and near the bottom, primarily in the 10–30-day period band. These oscillations are associated with 10–20-day (biweekly) and 20–30-day (monthly) Yanai waves. The strongest biweekly energy occurs in the upper 100 m between 45° and 95°E, where vertical mode-2 Yanai waves dominate and are primarily driven by meridional wind stress. The monthly Yanai wave energy is enhanced in two source regions: 1) the offshore western boundary (45°–55°E) in the upper 200 m, where mode-2 Yanai waves are excited by the convergence of eddy kinetic energy, and 2) the surface layer between 55° and 73°E, where meridional wind stress inputs energy, forcing predominantly mode-2 Yanai waves on a 20–30-day time scale. In addition, a subsurface trapping region for monthly Yanai waves lies between 55° and 95°E at 50–500 m, collocated with a subsurface maximum of 20–30-day meridional kinetic energy and dominated by higher-order baroclinic modes (3–5). Yanai wave energy excited in the upper layer propagates eastward and downward, leading to bottom-enhanced oscillations near sloping seafloor regions, notably west of the Maldives (60°–73°E) and near the Ninety East Ridge (85°–95°E). Meridional wind stress is the primary energy source for Yanai waves in the surface layer, while barotropic instability and vertical pressure work drive Yanai waves in the deep ocean.

中文摘要

摘要 在赤道印度洋，观测资料和全球海洋再分析与模拟（GLORYS）数据集揭示了上层500米及近底层经向流速的显著季节内变异，主要集中于10–30天周期波段。这些振荡与10–20天（双周）和20–30天（月）亚内波相关。最强的双周能量出现在45°E至95°E之间的上层100米，其中垂直模态2的亚内波占主导地位，且主要由经向风应力驱动。月亚内波能量在两个源区增强：1）上层200米内的离岸西边界（45°–55°E），该处涡动能辐合激发模态2亚内波；2）55°E至73°E之间的表层，经向风应力输入能量，在20–30天时间尺度上主要强迫模态2亚内波。此外，月亚内波的一个次表层捕获区域位于55°E至95°E之间的50–500米深度，与20–30天经向动能的次表层最大值位置重合，并由高阶斜压模态（3–5）主导。上层激发的亚内波能量向东和向下传播，导致近倾斜海底区域出现底层增强振荡，尤其在马尔代夫以西（60°–73°E）和东经九十度海岭附近（85°–95°E）。经向风应力是表层亚内波的主要能量来源，而正压不稳定性和垂直压力做功则驱动深海亚内波。

11. JPO — A Frictional Control Mechanism of Circumpolar Transport in Barotropic Reentrant Channel Models

Abstract

Abstract Recent studies have reported that an increase in the bottom drag coefficient can enhance the volume transport of the Antarctic Circumpolar Current. Several mechanisms have been proposed to explain this frictional control, including the regulation of the geostrophic velocity by baroclinic instability and the influence of the form stress associated with standing meanders and wind-driven gyres. In this study, the role of momentum transport associated with Rossby wave radiations from disturbances is investigated as a potential frictional control mechanism. To highlight roles of the Rossby wave radiation, numerical experiments are conducted using barotropic reentrant channel models with topographic obstacles. In the high-drag regime, the circumpolar component is wind driven, and the imbalance between the westerlies and topographic form stress sustains a net eastward transport. In contrast, in the low-drag regime, the eddy-driven westward circumpolar current is formed. In this case, the eastward flow at the center of the double gyre becomes unstable to barotropic instability. Analyses of the wave activity flux and momentum budget indicate that the Rossby wave transports westward momentum both northward and southward from the unstable region, which is responsible for the westward circumpolar current formation and maintenance. Although the direct application of the barotropic channel model to oceans requires caution, our findings imply that Rossby wave radiations from jets may play a role in the frictional control of the Antarctic Circumpolar Current.

中文摘要

摘要 近期研究报道指出，底部拖曳系数的增加可增强南极绕极流的体积输运。已有多种机制被提出用以解释这种摩擦控制作用，包括斜压不稳定性对地转流速的调控，以及伴随定常弯曲和风生涡旋的地形应力影响。本研究将扰动引起的罗斯贝波辐射所伴随的动量输运作为潜在的摩擦控制机制进行探讨。为突出罗斯贝波辐射的作用，采用带有地形障碍的正压再入通道模型开展数值实验。在高拖曳系数条件下，绕极分量由风驱动，西风带与地形应力之间的不平衡维持了净向东输运。相反，在低拖曳系数条件下，形成了涡旋驱动的向西绕极流。此时，双涡旋中心区域的东向流因正压不稳定性变得不稳定。波活动通量与动量收支分析表明，罗斯贝波从不稳定区域向北和向南输运西向动量，这导致了向西绕极流的形成与维持。尽管将正压通道模型直接应用于海洋需谨慎，但我们的研究结果表明，来自急流的罗斯贝波辐射可能在南极绕极流的摩擦控制中发挥作用。

12. JPO — Seasonal Changes in Dense Water Production Do Not Cause Seasonal Cycle in Atlantic Overturning

Abstract

Abstract The overturning circulation in the subpolar North Atlantic and Nordic seas is the product of a net densification by air–sea buoyancy forcing and mixing that transforms light Atlantic Water into dense North Atlantic Deep Water. Recent studies have shown that the magnitude of the time-mean overturning circulation as measured at the Overturning in the Subpolar North Atlantic Program (OSNAP) mooring array can be attributed to the water mass transformation by air–sea fluxes and mixing to the north of the array. However, connecting subpolar overturning variability on seasonal time scales to seasonal variations in water mass transformation is contentious. Here, we show in observations and a state estimate that seasonal variability in water mass transformation by air–sea buoyancy fluxes and mixing predominantly affects the storage of water in water mass classes within the subpolar basins, rather than driving seasonal changes in the overturning circulation at the OSNAP mooring array. Furthermore, we show that the seasonal formation and export of dense water from the Irminger and Labrador Seas cannot fully explain overturning seasonality at OSNAP. Instead, the seasonal cycle of overturning as measured at the OSNAP mooring array is the result of seasonal imbalances in the inflows and outflows of dense water across the array, linked to seasonal changes in the density field imprinted on the circulation of the subpolar gyre. This implies that intra-annual-to-seasonal dense water transport variability at OSNAP cannot be interpreted as an overturning circulation associated with the formation and export of dense water.

中文摘要

摘要 亚极地北大西洋和北欧海的翻转环流是海气浮力强迫与混合共同作用的结果，这种作用通过净密度增加将轻质大西洋水转化为重质北大西洋深层水。近期研究表明，在亚极地北大西洋翻转计划（OSNAP）锚系阵列观测到的时间平均翻转环流强度，可归因于该阵列以北区域的海气通量与混合引起的水团转化。然而，将亚极地翻转环流在季节时间尺度上的变率与水团转化的季节变化联系起来仍存在争议。本文通过观测资料与状态估计表明，海气浮力通量与混合引起的水团转化季节变率主要影响亚极地海盆内水团等级的水体储存，而非驱动OSNAP锚系阵列处翻转环流的季节变化。此外，研究显示伊尔明格海与拉布拉多海重质水的季节性生成与输出无法完全解释OSNAP处的翻转环流季节变化。实际上，OSNAP锚系阵列观测到的翻转环流季节循环，是该阵列处重质水流入与流出量季节性失衡的结果，这种失衡与亚极地环流中密度场印刻的季节变化密切相关。这意味着OSNAP处年内至季节尺度的重质水输送变率，不能解释为与重质水生成和输出相关的翻转环流。

13. JPO — Instability of the Halocline at the North Pole

Abstract

Abstract In this paper, we address the issue of stability for the near-inertial Pollard waves, as a model for the halocline in the region of the Arctic Ocean centered around the North Pole, derived in Puntini’s 2026 paper in Differential Integral Equations . Adopting the short-wavelength instability approach, the stability of such flows reduces to studying the stability of a system of ODEs along fluid trajectories, leading to the result that, when the steepness of the near-inertial Pollard waves exceeds a specific threshold, those waves are linearly unstable. The explicit dispersion relation of the model allows us to easily compute such a threshold, knowing the physical properties of the water column.

中文摘要

摘要 本文研究了近惯性波拉德波的稳定性问题，该波作为以北极点为中心的北冰洋区域盐跃层的模型，源自Puntini在2026年发表于《微分与积分方程》期刊的论文。采用短波长不稳定性方法，此类流动的稳定性可归结为沿流体轨迹的常微分方程系统的稳定性分析，结果表明：当近惯性波拉德波的陡度超过特定阈值时，这些波呈现线性不稳定性。该模型的显式色散关系使我们能够根据水柱的物理特性便捷地计算该阈值。

14. JPO — Is There a Preferred Choice to Parameterize the Stokes Expansion for Surface Gravity Waves?

Abstract

Abstract Nonlinear deep-water gravity waves can be described by Stokes-type perturbation expansions, but these are not unique. Multiple formulations exist that differ in how the perturbation amplitude is defined. We introduce a parameterized family of solutions and examine how different choices affect key wave characteristics—wave height, action, energy, momentum, and variance—in both deterministic and stochastic frameworks. For the parameterized form that aligns with the limit of the Zakharov equation for a single free-wave component, fourth-order corrections vanish from action and momentum, yielding a form that generalizes naturally to irregular and wave fields interacting with the environment. We discuss why different formulations arise in the literature and argue that while in general application dependent, this generalization property makes this the preferred form when considering the interaction of waves with the environment.

中文摘要

摘要 非线性深水重力波可通过斯托克斯型摄动展开描述，但此类展开并非唯一。存在多种表述形式，其差异在于摄动振幅的定义方式。我们引入参数化解族，并考察不同选择如何影响确定性及随机框架下的关键波特征——波高、作用量、能量、动量及方差。对于与单自由波分量扎哈罗夫方程极限一致的参数化形式，其作用量与动量的四阶修正项消失，从而自然推广至不规则波场及与环境相互作用的波场。我们探讨了文献中不同表述形式的成因，并论证：尽管通常依赖于具体应用场景，但该推广特性使其成为考虑波-环境相互作用时的首选形式。

15. JPO — Global Deep Ocean Observations of Horizontal Eddy–Mean Interactions of Temperature Variance

Abstract

Abstract Ocean eddies are ubiquitous in the ocean. Characterizing and quantifying their impact on the large-scale ocean circulation is key. Here, we compute eddy–mean interactions for Conservative Temperature variance, including temperature variance transfers. This is done using the ANDRO dataset, which records mean temperature and horizontal displacement of Argo floats during their journey at parking depth (∼1000 m). The analysis does not show any consistency between the sign of the turbulent heat flux and the slope of the mean isotherms, questioning the validity of traditional downgradient flux turbulent closure in the context of the temperature variance budget. The temperature variance interactions suggest the dominance of the nonlocal, redistribution term over the local, transfer term. They both have typical spatial scales ranging from 200 to 1000 km. When averaged over large regions, transfers are from the mean to the turbulence, but the northwest Atlantic remains a unique region which acts as a turbulence graveyard. Within a water-mass framework, transfers are quite consistently shrinking the mean temperature distribution except for a few extreme water masses: the Arctic Intermediate Water, the Antarctic Bottom Water, and the Red Sea–Persian Gulf Intermediate Water. This is also the case for a subset of the Mediterranean Water. However, the Mediterranean Water is the main location of the sharpening of the mean temperature distribution. These results provide observational evidence of the action of the turbulence on the mean temperature structure that could be tested in numerical ocean and climate models for validation and for the development and the implementation of ocean turbulent closures.

中文摘要

摘要 海洋涡旋在海洋中普遍存在。表征并量化它们对大尺度海洋环流的影响至关重要。本文基于保守温度方差（包括温度方差传递）计算了涡旋与平均流的相互作用。研究使用了ANDRO数据集，该数据集记录了阿尔戈浮标在驻留深度（约1000米）航行期间的平均温度与水平位移。分析显示，湍流热通量的符号与平均等温线斜率之间缺乏一致性，这质疑了传统降梯度湍流闭合在温度方差收支中的有效性。温度方差相互作用表明，非局地的再分布项主导了局地的传递项。两者均具有200至1000公里的典型空间尺度。在大区域平均下，能量从平均流向湍流传递，但西北大西洋仍是一个独特的区域，充当着湍流“墓地”。在水团框架内，除少数极端水团（如北极中层水、南极底层水、红海-波斯湾中层水）外，传递过程相当一致地压缩了平均温度分布。地中海水的子集也呈现类似特征。然而，地中海水是平均温度分布锋面增强的主要区域。这些结果为湍流对平均温度结构的作用提供了观测证据，可用于数值海洋与气候模式的验证，以及海洋湍流闭合方案的开发与实施。

16. JPO — Inertial Oscillations Disintegrating Coherent Vortices

Abstract

Abstract We study the disintegration of coherent vortices due to interaction with inertial oscillations using a two-vertical-mode model. For this, we generated and examined 640 flow regimes by varying the Rossby number and baroclinic–barotropic energy ratio. Based on the study, we find that increasing the Rossby number while keeping the same energy ratio and increasing the energy ratio at the same Rossby number can lead to faster disintegration of vortices. Exploring physical space regions partitioned into strain-dominant and vorticity-dominant regions, we see that disintegrating vortices have forward energy flux located in strain-dominant regions, while slightly weaker inverse energy flux is seen in vorticity-dominant regions. The net effect results in a forward cascade of the flow. Multiple phenomenological changes in the disintegration process are also seen on comparing anticyclonic and cyclonic vortices. The findings of this study in general help develop an understanding of the energy levels and Rossby number needed for unbalanced flows to disintegrate balanced flows in a broad regime going from small to O (1) Rossby numbers, this being the Rossby number transition seen as we move from mesoscales to submesoscales in the world’s oceans.

中文摘要

摘要 我们利用双垂直模态模型研究了相干涡旋因与惯性振荡相互作用而发生的解体过程。为此，通过改变罗斯比数和斜压-正压能量比，生成并分析了640种流动状态。研究发现，在保持相同能量比的情况下增大罗斯比数，以及在相同罗斯比数下增大能量比，均会导致涡旋解体加速。通过将物理空间区域划分为应变主导区和涡度主导区，我们发现解体涡旋的正向能量通量位于应变主导区，而涡度主导区则存在略弱的逆向能量通量。净效应导致流动呈现正向级联。对比反气旋涡与气旋涡时，还观察到解体过程中的多种现象学变化。本研究结果总体上有助于理解从较小罗斯比数到O(1)量级罗斯比数的广泛范围内（即世界海洋中从中尺度向亚中尺度过渡时观测到的罗斯比数转变），非平衡流解体平衡流所需的能量水平和罗斯比数。

17. JGR: Oceans — Seismic Effects of Large Earthquakes on Sea‐Level Budget Closures

Abstract

Abstract Large submarine earthquakes introduce significant distortions into the ocean bottom pressure (OBP) data from the Gravity Recovery and Climate Experiment (GRACE) and its follow‐on mission (GRACE‐FO), leading to non‐closure of regional sea‐level budgets in seismically active oceans. In this study, we show that earthquake‐induced seafloor deformations can be effectively isolated using an iterative Empirical Orthogonal Function method that accounts for both co‐seismic and post‐seismic effects. The resulting seismic biases are systematic, driven by ongoing tectonic drift, and can (a) exceed total steric contributions to sea‐level change in some regions and (b) surpass Glacial Isostatic Adjustment (GIA) contributions in the global mean. These findings indicate that seismic deformation represents a non‐negligible component for separating natural and human‐driven contributions in climate assessments. Applying the seismic corrections to the OBP fields restores regional sea‐level budget closure and improves the physical consistency of oceanographic and climate analyses.

中文摘要

大型海底地震会对重力恢复与气候实验（GRACE）及其后续任务（GRACE‐FO）的海洋底部压力（OBP）数据引入显著畸变，导致地震活跃海域区域海平面预算无法闭合。本研究表明，采用考虑同震和震后效应的迭代经验正交函数方法，可有效分离地震引起的海底形变。由此产生的地震偏差具有系统性，由持续进行的构造漂移驱动，并且可能（a）在某些区域超过海平面变化的总比容贡献，以及（b）在全球平均中超过冰川均衡调整（GIA）的贡献。这些发现表明，在气候评估中分离自然与人为驱动因素时，地震形变是一个不可忽略的组成部分。将地震校正应用于OBP场可恢复区域海平面预算的闭合性，并提升海洋学与气候分析的物理一致性。

18. JGR: Oceans — Global Assessment of Historical Changes in Ocean Wave Seasonality From Satellite Observations and an Integrated Model Ensemble

Abstract

Abstract Ocean waves influence maritime navigation safety and offshore infrastructure while contributing to coastal hazards such as erosion and flooding. Understanding the seasonality of extreme waves and how it changes over time is critical for anticipating these impacts. Here we present the first comprehensive global assessment of the seasonality of extreme waves using a multi‐mission satellite altimetry data set and a multi‐model wave ensemble. We quantify the mean seasonal cycle of extreme waves, its historical changes, and compare results from observations versus models to identify robust patterns and uncertainties. Further, we compare our results to changes in the storm surge seasonal cycle to identify common influences from large‐scale climate modes. Satellite and model results show strong spatial agreement in wave seasonality, but satellite data captures greater variability in the amplitude of the cycle over time. Overall, the Northern Hemisphere exhibits larger amplitude fluctuations, while places like the equatorial Pacific experienced isolated extremes in the past when the amplitude of the seasonal cycle was unusually large. Modes of climate variability affect both waves and storm surge seasonal cycles, often in phase. Our results advance understanding of the global seasonality of extreme waves and its temporal evolution, revealing consistent signals across data sets and highlighting regions of uncertainty. Finding shared climate influences for wave and storm surge cycles provides new insight into compound coastal hazards. While our analysis focuses on offshore wave climate, the results offer a steppingstone to improve downstream coastal hazard assessments, infrastructure design, and resilient coastal management at regional to global scales.

中文摘要

摘要 海浪影响海上航行安全与离岸基础设施，同时加剧海岸侵蚀和洪水等灾害。理解极端海浪的季节性及其随时间的变化，对于预测这些影响至关重要。本文利用多任务卫星测高数据集和多模式波浪集合，首次对极端海浪的季节性进行了全球综合评估。我们量化了极端海浪的平均季节循环、其历史变化，并对比观测与模式结果，以识别稳健模式与不确定性。此外，我们将结果与风暴潮季节循环的变化进行比较，以识别大尺度气候模态的共同影响。卫星与模式结果在波浪季节性上显示出强烈的空间一致性，但卫星数据捕捉到季节循环振幅随时间变化的更大变异性。总体而言，北半球表现出更大的振幅波动，而赤道太平洋等地区在过去季节循环振幅异常大时经历了孤立极端事件。气候变率模态同时影响波浪和风暴潮季节循环，且通常同相位。我们的研究结果增进了对全球极端海浪季节性及其时间演变的认知，揭示了数据集间的一致信号，并突出了不确定性区域。发现波浪与风暴潮循环共享的气候影响，为复合海岸灾害提供了新见解。尽管分析聚焦于离岸波浪气候，但结果为改进下游海岸灾害评估、基础设施设计以及区域至全球尺度的韧性海岸管理提供了基础。

19. JC — Disentangling regional impacts of joint teleconnections using causal representation learning

Abstract

Abstract Understanding teleconnections of large-scale modes of climate variability is relevant for seasonal predictability and supports a dynamical understanding of climatic changes. While numerical model experiments are the most common approach for investigating counterfactual climate responses, their conclusions are subject to model biases. Data-driven approaches offer a complementary perspective. Deep learning can extract reduced-dimensional patterns but usually lacks causal interpretability, while causal methods can disentangle signals in the presence of confounding yet are typically based on simple indices. Treating dimensionality reduction and causal inference separately thereby risks losing the teleconnection signal of interest. This paper introduces DAG-VAE, a causal representation learning approach that embeds a physics-informed directed acyclic graph in the latent space of a variational autoencoder. Combining deep learning with causal inference, the method jointly learns nonlinear reduced representations of large-scale modes of variability and their causal interactions. We apply DAG-VAE to disentangle the influences of the Pacific and Indian Oceans on the short rains over the Greater Horn of Africa. Trained on seasonal hindcasts, the method identifies dynamically meaningful representations and recovers spatial response patterns consistent with SST-replacement experiments. Trained on observations and reanalysis data, DAG-VAE identifies a different response pattern to direct influence of the tropical Pacific, highlighting potential model biases and the value of DAG-VAE as a complementary, data-driven approach for estimating spatial causal response patterns from observations. Finally, we demonstrate the ability of the method to generate data-driven counterfactuals of extreme short rain seasons, with potential applications for forecast-based early action and scenario planning.

中文摘要

摘要 理解大尺度气候变率模态的遥相关对于季节可预测性具有重要意义，并有助于从动力学角度理解气候变化。虽然数值模式实验是研究反事实气候响应的最常用方法，但其结论受模式偏差影响。数据驱动方法提供了互补视角。深度学习能够提取降维模式，但通常缺乏因果可解释性；而因果方法可在存在混杂因素时分离信号，但通常基于简单指数。将降维与因果推断分开处理，可能丢失关键的遥相关信号。本文提出DAG-VAE方法，这是一种因果表征学习方法，通过在变分自编码器的隐空间中嵌入物理信息有向无环图。该方法将深度学习与因果推断相结合，联合学习大尺度变率模态的非线性降维表征及其因果相互作用。我们将DAG-VAE应用于分离太平洋和印度洋对大非洲之角短雨季的影响。基于季节后报数据训练，该方法识别出具有动力学意义的表征，并恢复了与海表温度替换实验一致的空间响应模式。基于观测和再分析数据训练时，DAG-VAE识别出热带太平洋直接影响的不同响应模式，揭示了潜在的模式偏差，并凸显了DAG-VAE作为从观测中估计空间因果响应模式的互补性数据驱动方法的价值。最后，我们展示了该方法生成极端短雨季数据驱动反事实的能力，在基于预报的早期行动和情景规划中具有潜在应用价值。

20. JAMES — Effects of Wintertime Snow Depth Assimilation on Summertime Sea Ice Prediction Experiments Utilizing a Fully Coupled Regional Arctic Model With Perfect Boundary Conditions

  • 作者：Xi Liang, Chengyan Liu, Xichen Li, Zhongxiang Tian, Zhuoming Ding, Fu Zhao, Min Li, Na Liu, Jiaying Huang
  • 发表日期：2026-06-26
  • DOI：https://doi.org/10.1029/2025ms005521

Abstract

Abstract During the past decades, the rapid decline of sea ice in the Arctic Ocean has substantially favored commercial navigation activities in the summertime. Numerical sea ice prediction on a seasonal scale plays a crucial role in guiding the programme of such activities, yet the role of snow depth data assimilation in numerical sea ice prediction has not been clearly addressed in previous studies. With the aid of a coupled Arctic sea ice‒ocean‒atmosphere modeling system, two sets of runs have been conducted: one assimilates sea ice concentration, sea ice thickness, and sea surface temperature in the ice‐free region; the other one also assimilates snow depth overlying the ice synchronously. We have found that driven by perfect boundary conditions, wintertime snow depth assimilation generally has a positive effect on the September sea ice prediction initialized in early June, and the positive effect gradually weakens along with the delay of prediction onset from early June to early August. The effect has an intimate relationship with the changes in sea ice thickness and snow depth in the model state at the prediction onset, which eventually affects September sea ice prediction in the coupled system via model physics.

中文摘要

摘要 过去几十年间，北冰洋海冰的快速消退显著促进了夏季商业航行活动。季节尺度上的数值海冰预测对于指导此类活动的规划具有关键作用，然而以往研究尚未明确阐述雪深资料同化在数值海冰预测中的作用。借助北极海冰-海洋-大气耦合模拟系统，本研究开展了两组试验：一组同化海冰密集度、海冰厚度及无冰区域的海表温度；另一组则同步同化冰上雪深。研究发现，在完美边界条件驱动下，冬季雪深同化对以6月初为初始时刻的9月海冰预测总体具有积极影响，且该积极影响随预测起始时间从6月初推迟至8月初而逐渐减弱。这种影响与预测起始时刻模型状态中海冰厚度和雪深的变化密切相关，并最终通过模型物理过程影响耦合系统中的9月海冰预测。

21. JAMES — On the Cell Broadening of Mesoscale Cellular Convection in a Well‐Mixed Boundary Layer

Abstract

Abstract Understanding what controls the horizontal scale of mesoscale cellular convection is central to explaining cloud self‐organization and its radiative impacts. Using a hierarchy of large‐eddy simulations, we investigate cell broadening in a well‐mixed boundary layer by isolating the roles of radiation, cloud microphysics, and water vapor. In cloudy simulations, cellular convection develops large aspect ratios (∼20–30) and forms donut‐like open cells with thick cloud walls, where open cells are defined dynamically based on the water‐vapor perturbation field. Even when radiative and microphysical effects are entirely removed, water vapor alone still self‐organizes into cellular structures with aspect ratios of ∼10. In these vapor‐only simulations, cell size is regulated primarily by surface sensible heat flux under the necessary condition of surface moisture supply, while remaining largely insensitive to the absolute magnitude and vertical distribution of water vapor. We identify mixing‐induced cooling across the entrainment interface layer (EIL) as the key mechanism enabling cell broadening without cloud‐related feedbacks. Within this idealized framework, we introduce Δ s l /Δ z i , the mean gradient of liquid water static energy across the EIL, as a post‐hoc and process‐oriented diagnostic to quantify the relative strength of mixing‐induced cooling across the EIL. Composite stream‐function analysis reveal qualitatively similar mesoscale overturning circulations in cloudy and vapor‐only simulations, highlighting the role of cooling effects across the EIL in cellular organization. These results reveal a pathway for cell broadening in water‐vapor‐only conditions and underscore the need for future work on the nonlinear interplay among mixing, radiation, and microphysics in regulating mesoscale cellular organization.

中文摘要

摘要 理解中尺度蜂窝状对流水平尺度的控制因素，是解释云自组织及其辐射效应的核心。通过一系列大涡模拟，我们隔离了辐射、云微物理和水汽的作用，研究了充分混合边界层中蜂窝结构的扩展现象。在有云模拟中，蜂窝状对流发展出较大的纵横比（约20–30），并形成具有厚云壁的甜甜圈状开放细胞，其中开放细胞基于水汽扰动场动态定义。即使完全移除辐射和微物理效应，仅水汽本身仍能自组织成纵横比约10的蜂窝结构。在这些纯水汽模拟中，细胞尺度主要受地表感热通量调控（需满足地表水汽供给条件），而对水汽绝对含量及垂直分布不敏感。我们识别出夹卷界面层（EIL）中的混合诱导冷却是无需云相关反馈即可实现细胞扩展的关键机制。在此理想化框架下，引入Δs_l/Δz_i（即EIL内液态水静力能平均梯度）作为事后且面向过程的诊断量，以量化EIL中混合诱导冷却的相对强度。复合流函数分析显示，有云模拟与纯水汽模拟中均存在定性相似的中尺度翻转环流，凸显了EIL冷却效应对蜂窝组织的作用。这些结果揭示了纯水汽条件下细胞扩展的路径，并强调未来需研究混合、辐射与微物理之间的非线性相互作用对中尺度蜂窝组织的调控机制。

22. GRL — Increases in Southeast Pacific Low‐Cloudiness During ENSO Warm Phases

Abstract

Abstract Changes in cloud fraction associated with Central Pacific and Eastern Pacific El Niños are analyzed using monthly cloud data from the International Satellite Cloud Climatology Project, meteorological variables from the European Center for Medium Range Weather Forecasting reanalysis version 5, and radiation data from the Clouds and the Earth’s Radiant Energy System. We observe robust increases in low cloud fraction in the tropical Southeast Pacific (SEP, 120°–80°W 0°–20°S) during El Niños. The increases in SEP low‐cloudiness are associated with CP‐El Niño variability. Increases in SEP Sea Surface Temperature during CP‐El Niños are accompanied by a warmer tropical free troposphere, increased cold advection, and reduced overlying cirrus, facilitating the growth of low clouds. Northeast Pacific cloud decks decrease during El Niños, consistent with weaker free‐tropospheric heating outside the tropics. Coupled CMIP6 model experiments are unable to replicate increased SEP low cloud due to a misrepresentation of El Niño Southern Oscillation diversity.

中文摘要

摘要 利用国际卫星云气候计划提供的月平均云量数据、欧洲中期天气预报中心第五代再分析资料的气象变量以及云与地球辐射能量系统的辐射数据，分析了与中太平洋和东太平洋厄尔尼诺事件相关的云量变化。我们观察到在厄尔尼诺期间，热带东南太平洋（SEP，120°–80°W 0°–20°S）的低云量显著增加。SEP低云量的增加与中太平洋型厄尔尼诺（CP-El Niño）变率相关。在CP-El Niño期间，SEP海表温度升高伴随着热带自由对流层变暖、冷平流增强以及上层卷云减少，这有利于低云的发展。厄尔尼诺期间东北太平洋云层减少，与热带外地区自由对流层加热减弱一致。耦合的CMIP6模式实验由于未能准确表征厄尔尼诺-南方涛动多样性，无法再现SEP低云量的增加。

23. GRL — Weak 21st‐Century AMOC Response to Greenland Meltwater in a Strongly Eddying Ocean Model

Abstract

Abstract Climate models project that the Atlantic Meridional Overturning Circulation (AMOC) will weaken in the 21st century, but the magnitude is highly uncertain. Some of this uncertainty is structural, as most climate models neglect increasing meltwater from the Greenland ice sheet and do not explicitly capture mesoscale ocean eddies. Here, we quantify the impact of Greenland meltwater on the AMOC until 2100 under SSP5‐8.5 forcing for the first time in a strongly eddying (1/10° horizontal resolution) ocean model. The meltwater‐induced additional AMOC weakening is small (0.6 0.2 Sv) compared to the weakening due to warming alone, and similar at high and low resolution. The same meltwater would cause a stronger AMOC weakening under present‐day climate conditions. We link both resolution‐independence and state‐dependence to large‐scale controls of the AMOC. Our results demonstrate that the background ocean state is more important than resolution in determining how Greenland meltwater affects the AMOC.

中文摘要

摘要 气候模式预测，大西洋经向翻转环流（AMOC）将在21世纪减弱，但其幅度具有高度不确定性。这种不确定性部分源于结构性问题，因为大多数气候模式忽略了格陵兰冰盖持续增加的融水，且未能显式捕捉中尺度海洋涡旋。本研究首次在强涡旋分辨（1/10°水平分辨率）海洋模式中，量化了SSP5‐8.5强迫情景下格陵兰融水对AMOC直至2100年的影响。与仅由变暖导致的AMOC减弱相比，融水引起的额外AMOC减弱幅度较小（0.6±0.2 Sv），且在高分辨率和低分辨率下结果相似。在当代气候条件下，同等融水量将导致更强的AMOC减弱。我们将分辨率无关性和状态依赖性均归因于AMOC的大尺度控制机制。研究结果表明，在决定格陵兰融水如何影响AMOC时，背景海洋状态比模式分辨率更为重要。

24. GRL — Opposite Trends of Eddy Kinetic Energy in the Tropical Indo‐Pacific Ocean Since the 1990s

Abstract

Abstract Oceanic mesoscale eddies are pivotal in redistributing mass and heat. Despite a warming‐induced increase in global oceanic stratification, previous studies have reported a global increase in mesoscale eddy activity, particularly in eddy‐rich regions, pointing to a complex and regionally contingent response to climate change. Here we show that the eddy kinetic energy (EKE) over the two wings of the tropical Indo‐Pacific Ocean shows an opposite trend over the past three decades, with a pronounced decreasing in the western tropical Pacific Ocean (WTPO) but a significant increasing in the southeastern tropical Indian Ocean (SETIO). We find that the EKE decline in the WTPO is mainly due to weakened intra‐seasonal wind work, while the EKE increase in SETIO is mainly driven by weakened stratification in the north and enhanced shear in the south, both of which are associated with the intensified Indonesian Throughflow.

中文摘要

摘要 海洋中尺度涡旋在物质和热量的再分配中起着关键作用。尽管全球海洋层结因变暖而增强，但先前的研究报告指出全球中尺度涡旋活动有所增加，尤其是在涡旋富集区域，这表明其对气候变化的响应具有复杂性和区域性。本研究发现，过去三十年间，热带印度-太平洋两侧海域的涡动能呈现相反趋势：西热带太平洋区域显著下降，而东南热带印度洋区域则明显上升。分析表明，西热带太平洋涡动能的下降主要归因于季节内风应力做功的减弱，而东南热带印度洋涡动能的增加则主要源于北部层结减弱和南部剪切增强，这两者均与印度尼西亚贯穿流的增强有关。

25. GRL — Tropical Pacific as a Pacemaker of Recent Decadal Anticyclonic Intensification Over the Barents–Kara Sea

Abstract

Abstract Under anthropogenic warming, a strengthened wintertime anticyclonic anomaly over the Barents–Kara Sea (BKS) has emerged as a hallmark of recent Arctic climate change. While local forcing from sea ice loss has been widely emphasized, the quantitative contribution of remote tropical forcing remains poorly constrained. Here we demonstrate that decadal La Niña–like cooling in the eastern tropical Pacific has been a key remote driver of this circulation change. This Niña–like cooling reorganizes tropical convection and excites a stationary Rossby wave train, generating a trans‐basin response that induces an anticyclonic anomaly over the BKS. This mechanism accounts for 27 ± 17% of the circulation trend and interacts with anthropogenic forcing to amplify Arctic climate change. Our results underscore the critical role of tropical Pacific decadal variability in recent regional Arctic circulation changes, with implications for climate in the Arctic and beyond.

中文摘要

摘要 在人为变暖背景下，巴伦支海-喀拉海（BKS）上空冬季反气旋异常增强已成为近期北极气候变化的一个标志性特征。尽管局地海冰减少的强迫作用已被广泛强调，但远程热带强迫的定量贡献仍缺乏明确约束。本文证明，热带东太平洋年代际类拉尼娜冷异常是这一环流变化的关键远程驱动因子。这种类拉尼娜冷异常重组了热带对流活动，并激发定常罗斯贝波列，产生跨海盆响应，从而在BKS上空诱导出反气旋异常。该机制解释了27±17%的环流趋势，并与人为强迫相互作用，放大了北极气候变化。我们的研究结果强调了热带太平洋年代际变率对近期区域北极环流变化的关键作用，并对北极及更广泛地区的气候具有重要影响。

26. GRL — Stratospheric Ozone Depletion Causes Southern Ocean Surface Cooling

Abstract

Abstract Stratospheric ozone depletion strongly influences Southern Ocean climate change. Using coupled climate model simulations, we quantify the transient effect of stratospheric ozone depletion on sea surface temperature (SST) over the Southern Ocean from 1982 to 2005. We find that stratospheric ozone depletion intensifies surface zonal winds south of 46°S, which increases northward Ekman transports and promotes cold water advection, resulting in SST cooling there. In addition, meridional SST gradients are enhanced across the Southern Ocean, which, in turn, prompt colder water advection driven by climatological surface winds to exacerbate the SST cooling between 46°S and 60°S. Because of the increase in stratospheric ozone depletion from 1982 to the early 2000s, the sustained Ekman transport induced horizontal cold‐water advection—though partially compensated by changes in surface heat flux and vertical advection below the mixed layer—plays a central role in maintaining Southern Ocean SST cooling and regional Antarctic sea ice expansion.

中文摘要

摘要 平流层臭氧损耗对南大洋气候变化具有显著影响。通过耦合气候模式模拟，我们量化了1982年至2005年间平流层臭氧损耗对南大洋海表温度（SST）的瞬态效应。研究发现，平流层臭氧损耗增强了46°S以南的表层纬向风，导致向北的埃克曼输送增强并促进冷水平流，从而引起该区域海表温度降低。此外，南大洋经向海表温度梯度随之增强，进而促使气候态表层风驱动的冷水平流加剧，导致46°S至60°S之间的海表温度进一步下降。由于1982年至21世纪初平流层臭氧损耗持续增加，持续的埃克曼输送所引发的水平冷水平流——尽管部分被海表热通量及混合层以下垂直平流的变化所补偿——在维持南大洋海表温度降低及区域南极海冰扩张中发挥了核心作用。

27. GRL — Calibration of a Neural Network Ocean Closure for Improved Mean State and Variability

Abstract

Abstract Global ocean models exhibit biases in the mean state and variability, particularly at coarse resolution, where mesoscale eddies are unresolved. To address these biases, parameterization coefficients are typically tuned ad hoc. Here, we formulate parameter tuning as a calibration problem using Ensemble Kalman Inversion (EKI). We optimize parameters of a neural network parameterization of mesoscale eddies in two idealized ocean models at coarse resolution. The calibrated parameterization reduces errors in the time‐averaged fluid interfaces and their variability by factors of 1.7–3.3 compared to the unparameterized model, depending on the metric and configuration. The EKI method is robust to noise in time‐averaged statistics arising from chaotic ocean dynamics. Furthermore, we propose an efficient calibration protocol that bypasses integration to statistical equilibrium by carefully choosing an initial condition. These results demonstrate that systematic calibration can substantially improve coarse‐resolution ocean simulations and provide a practical pathway for reducing biases in global ocean models.

中文摘要

全球海洋模式在平均态和变率方面存在偏差，尤其在粗分辨率下，中尺度涡旋无法被解析。为应对这些偏差，参数化系数通常采用临时调整方式。本文将参数调优构建为校准问题，利用集合卡尔曼反演（EKI）方法。我们在两个理想化粗分辨率海洋模式中优化了中尺度涡旋神经网络参数化方案的参数。与未参数化模式相比，经校准的参数化方案将时间平均流体界面及其变率的误差降低了1.7-3.3倍（具体取决于评估指标和配置）。EKI方法对混沌海洋动力学引起的时间平均统计量噪声具有鲁棒性。此外，我们提出了一种高效校准方案，通过精心选择初始条件避免积分至统计平衡态。这些结果表明，系统性校准可显著改善粗分辨率海洋模拟，并为减少全球海洋模式偏差提供了实用途径。

28. GRL — An Atmosphere–Land–Ocean Coupled Global NWP System: Performance Evaluation for Potential Operational Use

  • 作者：Sumit Kumar, Imranali M. Momin, Sukhwinder Kaur, Kondapalli Niranjan Kumar, Jonah Roberts‐Jones, Matthew J. Martin, John P. George, V. S. Prasad
  • 发表日期：2026-06-27
  • DOI：https://doi.org/10.1029/2025gl120923

Abstract

Abstract This study assesses the influence of ocean–atmosphere coupling on short‐ and medium‐range forecasts of the July 2024 Indian summer monsoon using the newly configured coupled NCMRWF Unified Model (C‐NCUM). Forecasts are evaluated against the operational atmosphere–land model (NCUM) using GPM rainfall, OSTIA SSTs, and reanalysis‐derived moisture fields. The C‐NCUM system demonstrates improved simulation of monsoon rainfall and SST variability, with notable reductions in widespread wet biases over the western equatorial Indian Ocean (WEIO) and the Core Monsoon Zone. Enhanced representation of SST–convection interactions and moisture transport reduces the spurious low‐level convergence present in the uncoupled forecasts. SST diagnostics also reveal reduced warm biases and higher spatial correlation with observations, particularly over the WEIO. Forecast skill remains weaker over the eastern equatorial Indian Ocean. The results highlight the importance of dynamic air–sea coupling for advancing monsoon prediction capability.

中文摘要

摘要 本研究利用新配置的耦合NCMRWF统一模式（C-NCUM），评估了海气耦合对2024年7月印度夏季风短期和中期预报的影响。基于GPM降水数据、OSTIA海表温度以及再分析导出的湿度场，将预报结果与业务化的大气-陆地模式（NCUM）进行对比评估。C-NCUM系统在季风降水和海表温度变率的模拟方面表现出改进，特别是在西赤道印度洋和核心季风区，大范围湿偏差显著减少。海表温度-对流相互作用及水汽输送的增强表征，减少了非耦合预报中存在的虚假低层辐合。海表温度诊断还显示，暖偏差有所降低，且与观测值的空间相关性更高，尤其是在西赤道印度洋区域。然而，预报技巧在东赤道印度洋仍较弱。研究结果强调了动态海气耦合对提升季风预测能力的重要性。

29. JC — Identifying Time Scales and Spatial Patterns of Upward and Downward Influences between the Wintertime Troposphere and Stratosphere

Abstract

Abstract The past few decades of work on stratosphere–troposphere teleconnections have unearthed a variety of different time scales of both upward and downward propagation and their connection to weather at the surface. In an attempt to identify significant patterns of covariance between the surface and the stratosphere without imposing an expected pattern or time scale, we apply maximum covariance analysis (MCA) with a variable time lag between pairs of tropospheric and stratospheric fields. Using over 60 years of ERA5 reanalysis for Northern Hemisphere winters, we use MCA to pick out the time lags and patterns corresponding to the largest covariance between the surface and the stratosphere. By applying new methods to an existing problem, we both verify certain results from previous literature and unearth new insights into the nature of stratosphere–troposphere teleconnections. We find that the greatest covariance occurs when the surface precedes the stratosphere by up to 9 days, corresponding to a sea level pressure anomaly with one pole over the Gulf of Alaska and another over the Ural blocking high that is followed by changes in stratospheric potential vorticity, zonal wind, and Eliassen–Palm (EP) flux. We find evidence for a downward influence of stratospheric potential vorticity and zonal wind on sea level pressure at a time scale of 3–4 days, with a secondary influence from zonal wind alone at 2–3 weeks. The downward influence is characterized by a weaker (stronger) polar vortex followed by anomalously high (low) sea level pressures over the Arctic Ocean, but it does not produce an appreciable anomaly in minimum surface temperatures. Significance Statement We seek to improve both predictability and fundamental understanding of the linkages between the troposphere, the convectively active layer of the atmosphere responsible for weather, and the stratosphere, the much more stable region just above it. We identify a key time scale of upward influence from the surface to the stratosphere of just over 1 week with distinct precursors at the surface. We also find a downward influence of the stratosphere on the surface at two time scales, the shorter about 3 days and the longer 2–3 weeks. However, this downward influence does not extend to a noticeable impact on minimum surface temperatures.

中文摘要

摘要 过去几十年关于平流层-对流层遥相关的研究揭示了多种不同时间尺度的向上和向下传播过程及其与地表天气的联系。为在不预设特定模态或时间尺度的前提下识别地表与平流层之间的显著协方差模态，我们采用具有可变时间滞后的最大协方差分析（MCA）方法，对对流层和平流层场对进行分析。基于北半球冬季超过60年的ERA5再分析资料，我们利用MCA提取了地表与平流层之间最大协方差对应的时间滞后和模态。通过将新方法应用于既有问题，我们既验证了前人文献中的部分结论，又获得了对平流层-对流层遥相关本质的新认识。研究发现，当地表变化超前平流层变化最多9天时协方差最大，对应海平面气压异常呈现阿拉斯加湾和乌拉尔阻塞高压两个极区，随后平流层位涡、纬向风和Eliassen-Palm（EP）通量发生改变。我们发现了平流层位涡和纬向风在3-4天时间尺度上对海平面气压的向下影响证据，以及仅由纬向风主导的2-3周次级影响。这种向下影响表现为极涡减弱（增强）后北冰洋海平面气压异常偏高（偏低），但并未对最低地表温度产生显著异常。意义声明 本研究旨在提升对对流层（负责天气的活跃大气层）与平流层（其上方更稳定的区域）之间联系的可预测性及基础理解。我们识别出地表向平流层向上影响的关键时间尺度约为1周，并伴有明确的地表前兆信号。同时发现平流层对地表存在两种时间尺度的向下影响：较短者约3天，较长者约2-3周。然而，这种向下影响并未延伸至对最低地表温度产生显著作用。

30. JC — On the Role of Ocean Dynamics in Polar-Amplified Climate Change

Abstract

Abstract Coupled general circulation models (GCMs) ubiquitously predict polar-amplified surface warming in response to increasing carbon dioxide (CO 2 ) concentrations but with significant variation in the magnitude of polar temperature rises. Here, we develop a simplified model of climate change over the global ocean to better understand the fundamental physics underpinning polar amplification and untangle the role of ocean dynamics in modulating its strength. Our model is composed of a forcing-feedback formulation for the surface energy balance coupled to the ocean circulation, with the atmosphere slaved to the ocean. Our results suggest that polar-amplified warming is a fundamental property of any climate where the poles are colder than the equator, due largely to the variation of the (negative) evaporative and (positive) longwave feedbacks with temperature. The evaporative feedback weakens more rapidly than the longwave feedback as temperature decreases, leading to larger temperature changes at the poles than at the equator. In our model, the polar oceans are highly sensitive to feedbacks associated with ocean dynamics, which we decompose into circulation and mixing. We find that the amplification of warming in both the Southern Ocean and the Arctic Ocean is most sensitive to the strength of the Atlantic meridional overturning circulation at centennial time scales and near-surface mixing at decadal time scales. There is also significant sensitivity of Southern Ocean temperature changes to the strength of the abyssal overturning, as well as the deep diapycnal mixing. As such, our results suggest that the differing representation of ocean dynamics in GCMs may partly explain their significant variation in the meridional structure of warming under CO 2 forcing. Significance Statement This work untangles the role of surface heating and ocean heat transport in driving enhanced surface warming over the polar oceans as the amount of atmospheric greenhouse gases increases. We show that polar-amplified warming can occur due to the differences in local surface heating at the colder poles compared to the warmer regions nearer the equator, without any changes in circulation or atmospheric structure. The ocean influences the amount and speed of this warming with stronger circulation and mixing generally resulting in reduced polar warming. However, this result can vary depending on the time and pole of interest. Our work may help explain the reasons behind the large variation in polar-amplified warming projected by climate models for the coming century.

中文摘要

摘要 耦合环流模式普遍预测，在二氧化碳浓度升高的情况下，极地表面增温会放大，但极地温度升高的幅度存在显著差异。本文构建了一个全球海洋气候变化的简化模型，以更深入地理解极地放大现象的基本物理机制，并厘清海洋动力过程在调节其强度中的作用。该模型由海表能量平衡的强迫-反馈公式与海洋环流耦合而成，大气则从属于海洋。结果表明，极地增温放大是任何极地温度低于赤道气候的基本属性，这主要归因于（负的）蒸发反馈和（正的）长波反馈随温度的变化。随着温度降低，蒸发反馈的减弱速度快于长波反馈，导致极地温度变化大于赤道。在模型中，极地海洋对与海洋动力过程相关的反馈高度敏感，我们将这些反馈分解为环流和混合。研究发现，南大洋和北冰洋增温的放大效应，在百年时间尺度上对大西洋经向翻转环流的强度最为敏感，而在十年时间尺度上则对近表层混合最为敏感。此外，南大洋温度变化对深层经向翻转环流和深层等密度面混合的强度也表现出显著敏感性。因此，我们的结果表明，耦合环流模式中海洋动力过程表征的差异，可能部分解释了在二氧化碳强迫下增温经向结构存在显著差异的原因。意义声明 本文厘清了海表加热和海洋热输送在驱动大气温室气体增加时极地海洋增温增强中的作用。研究表明，极地增温放大可能仅源于较冷极地与较暖赤道附近区域局地海表加热的差异，而无需环流或大气结构的变化。海洋通过更强的环流和混合通常导致极地增温减弱，从而影响增温的幅度和速度。然而，这一结果可能因时间和所关注的极地而异。本研究有助于解释气候模式预测未来百年极地增温放大存在较大差异的原因。

31. JC — The Impact of Barents Sea Ice Concentration on the Interannual Variation of Winter Extreme Cold Days over South China

Abstract

Abstract The occurrences of the winter extreme cold days (ECDs) over South China could often cause serious damages to the regional economy and livelihoods. Therefore, understanding their interannual variability is of broad scientific and socioeconomic interest. Based on the observation and reanalysis datasets, this work explores the effect of Barents Sea ice concentration (BRSIC) on the winter ECDs over South China during the period of 1978–2020. The results show that the interannual variation of the winter ECDs over South China is closely associated with that of BRSIC. An interannual reduction in the winter BRSIC tends to be accompanied by an increase in the ECDs over South China and vice versa. Specifically, the BRSIC reduction is closely coupled with Arctic warming through the positive ice–albedo feedback, ice-related moisture–latent heat release, and ice-advection feedback. A warmer Arctic elevates the geopotential height at the high latitudes, forming a meridional thickness gradient in the high- and midlatitudes of the Northern Hemisphere. The midlatitude westerly jet over continental Eurasia would be weakened consistent with the thickness gradient (thermal wind relationship), providing favorable background conditions for the long duration of Ural blocking events. As a result, under the equivalent barotropic atmospheric conditions, the prolonged Ural blocking events generate anticyclonic winds near the surface at both synoptic and climatological time scales, which could persistently transport cold air to South China, thereby increasing the local winter ECDs. In addition, the sensitivity experiments and climate model simulations have both confirmed this significant result. This study highlights the important role of the Eurasian westerly jet stream and long Ural blocking duration events in the impact of the winter Arctic sea ice processes on the extreme weather events over South China. Significance Statement In February 2008, a catastrophic winter snowstorm struck central and southern China, causing severe impacts on the regional agriculture, infrastructure, and human health. Therefore, the winter extreme cold days (ECDs) over South China are of particular socioeconomic concern. This study underscores the pivotal role of the Eurasian westerly jet stream, closely associated with the Barents Sea ice concentration (BRSIC), in modulating the winter ECDs over South China. This serves as a bridge between the winter Arctic sea ice processes and the midlatitude weather patterns. The present findings reveal that reduced BRSIC is accompanied by enhanced local Arctic warming through coupled feedbacks and, in turn, prolongs the Ural blocking events by weakening the midlatitude Eurasian westerly jet stream. As a result, this would facilitate the southward intrusion of cold air into South China, thereby increasing the local winter ECDs and vice versa. These results have an implication for the impact of the future Arctic sea ice reduction on the winter ECDs over South China under global warming.

中文摘要

摘要 华南冬季极端寒冷日（ECDs）的发生常对区域经济和民生造成严重损害。因此，理解其年际变率具有广泛的科学和社会经济意义。基于观测和再分析数据集，本研究探讨了1978–2020年期间巴伦支海海冰密集度（BRSIC）对华南冬季ECDs的影响。结果表明，华南冬季ECDs的年际变化与BRSIC的年际变化密切相关。冬季BRSIC的年际减少往往伴随着华南ECDs的增加，反之亦然。具体而言，BRSIC的减少通过正冰-反照率反馈、与冰相关的水汽-潜热释放以及冰平流反馈，与北极增暖紧密耦合。较暖的北极抬高了高纬度位势高度，在北半球高纬度和中纬度形成经向厚度梯度。与厚度梯度一致（热成风关系），欧亚大陆中纬度西风急流减弱，为乌拉尔阻塞事件的持续提供了有利背景条件。因此，在等效正压大气条件下，持续较长的乌拉尔阻塞事件在天气和气候时间尺度上均在地表附近产生反气旋风，可持续将冷空气输送至华南，从而增加当地冬季ECDs。此外，敏感性试验和气候模式模拟均证实了这一显著结果。本研究强调了欧亚西风急流和长持续乌拉尔阻塞事件在冬季北极海冰过程影响华南极端天气事件中的重要作用。意义声明 2008年2月，一场灾难性的冬季暴风雪袭击了中国中南部，对区域农业、基础设施和人类健康造成了严重影响。因此，华南冬季极端寒冷日（ECDs）具有特别的社会经济关注度。本研究强调了与巴伦支海海冰密集度（BRSIC）密切相关的欧亚西风急流在调节华南冬季ECDs中的关键作用。这成为冬季北极海冰过程与中纬度天气型之间的桥梁。本研究发现表明，BRSIC的减少通过耦合反馈伴随局地北极增暖增强，进而通过减弱中纬度欧亚西风急流延长乌拉尔阻塞事件。结果，这有利于冷空气向南侵入华南，从而增加当地冬季ECDs，反之亦然。这些结果对全球变暖背景下未来北极海冰减少对华南冬季ECDs的影响具有启示意义。

32. JC — Nonlinear Modulation of ENSO Condition on the Interannual Frequency Variation of Long-Lived Cross-Equatorial Flow Events over the Maritime Continent in Boreal Summer

Abstract

Abstract This study examines the interannual variability of cross-equatorial flow (CEF) event frequency (herein defined as the total count of event days) over the Maritime Continent during June–September, using reanalysis data from 1979 to 2020. Results show that the frequency of long-lived CEF events exhibits pronounced interannual variation and is closely related to El Niño–Southern Oscillation (ENSO) condition in simultaneous summer. Notably, this relationship is highly nonlinear, with difference in event frequency between El Niño and neutral years (∼30 days yr −1 ) far exceeding that between La Niña and neutral years (∼6 days yr −1 ). The relationship between ENSO and long-lived CEF events is established through ENSO’s modifications to the seasonal mean CEF, which serves as a background state for the occurrence of CEF events. Although the seasonal mean CEF anomalies under the warm and cold phases of ENSO are opposite and comparable, the effect of the background state on CEF events is fundamentally nonlinear. Specifically, the frequency of long-lived events is not sensitive to the CEF background state when it is lower than 0.51 m s −1 but becomes highly sensitive when the background state becomes stronger. Additionally, the boreal summer intraseasonal oscillation (BSISO) further modulates the interannual variation of long-lived CEF events: the active phases of BSISO can amplify the nonlinearity of the relationship between CEF events and ENSO, while the suppressed phases tend to narrow it. In contrast to long-lived events, the short-lived events exhibit relatively weak interannual variability, and this variability shows negligible relationship with ENSO.

中文摘要

摘要 本研究利用1979—2020年再分析资料，探讨了6—9月期间海洋大陆地区越赤道气流（CEF）事件频率（定义为事件总天数）的年际变率。结果表明，长生命期CEF事件的频率呈现显著的年际变化，且与同期夏季的厄尔尼诺-南方涛动（ENSO）条件密切相关。值得注意的是，这种关系具有高度非线性特征：厄尔尼诺年与中性年之间的事件频率差异（约30天/年）远大于拉尼娜年与中性年之间的差异（约6天/年）。ENSO与长生命期CEF事件之间的关联通过ENSO对季节平均CEF的调制作用建立，后者作为CEF事件发生的背景状态。尽管ENSO暖位相与冷位相下季节平均CEF异常的方向相反且量级相当，但背景状态对CEF事件的影响本质上具有非线性特征。具体而言，当背景CEF强度低于0.51米/秒时，长生命期事件频率对背景状态不敏感；但当背景状态增强后，其敏感性显著提高。此外，北半球夏季季节内振荡（BSISO）进一步调制长生命期CEF事件的年际变化：BSISO活跃位相可放大CEF事件与ENSO关系的非线性特征，而抑制位相则倾向于缩小这种非线性。与长生命期事件相比，短生命期事件的年际变率相对较弱，且该变率与ENSO的相关性可忽略不计。

33. JC — The Role of Atmosphere–Ocean Coupling on the Prediction of Madden–Julian Oscillation

Abstract

Abstract This study examines drivers affecting the prediction of tropical intraseasonal variability (30–90 days) with an application to the coupled model Unified Forecast System (UFS) prototype 8 (UFS P8). The Madden–Julian oscillation (MJO) and Kelvin and equatorial Rossby waves are assessed using the moist static energy (MSE) budget analysis applied to ERA5 reanalysis and UFS P8 subseasonal forecasts. Although UFS P8 represents the climatological mean of MSE and sea surface temperature (SST) well, it significantly overestimates their intraseasonal variability, particularly over the Maritime Continent. Notably, the MSE budget for the MJO in UFS P8 shows substantial discrepancies compared to ERA5 reanalysis, primarily driven by errors in surface latent heat flux, while the Kelvin and Rossby waves are reasonably simulated. The decomposition of surface latent heat flux into wind-driven and thermodynamic contributions indicates that, in UFS P8, wind-driven errors arise from surface wind biases, which may be attributed to the insufficient horizontal resolution to resolve complex coastlines, whereas thermodynamic errors result from the overestimation of SST variability. Further analysis employing Granger causality reveals that UFS P8 exhibits a stronger-than-observed atmosphere–ocean coupling, with SST being too sensitive to atmospheric forcing. The results suggest that uncertainties in vertical mixing parameterization in the upper ocean could contribute significantly to the enhanced coupling.

中文摘要

摘要 本研究探讨了影响热带季节内变率（30-90天）预测的驱动因素，并将其应用于耦合模式统一预报系统（UFS）原型8（UFS P8）。利用湿静力能（MSE）收支分析，基于ERA5再分析资料和UFS P8次季节预报，评估了马登-朱利安振荡（MJO）、开尔文波和赤道罗斯贝波。尽管UFS P8较好地再现了MSE和海表温度（SST）的气候态平均值，但显著高估了其季节内变率，尤其是在海洋大陆区域。值得注意的是，与ERA5再分析相比，UFS P8中MJO的MSE收支存在显著差异，这主要由表面潜热通量的误差驱动，而开尔文波和罗斯贝波的模拟则相对合理。将表面潜热通量分解为风驱动和热力学贡献后发现，在UFS P8中，风驱动误差源于表面风场偏差，这可能归因于水平分辨率不足以解析复杂海岸线；而热力学误差则源于对SST变率的高估。进一步采用格兰杰因果分析表明，UFS P8表现出比观测更强的大气-海洋耦合，SST对大气强迫过于敏感。结果表明，上层海洋垂直混合参数化的不确定性可能对增强的耦合有显著贡献。

34. JC — A Koopman Interpretation of the Recharge Oscillator Model for ENSO

Abstract

Abstract The mechanisms governing ENSO’s growth, decay, and phase transitions are encapsulated by the recharge oscillator model (ROM), a coupled pair of differential equations for equatorial sea surface temperature (SST) and thermocline depth. While the ROM can explain many of ENSO’s key characteristics, its representation of asymmetry is ambiguous owing to a lack of consensus about what processes are most important for observed ENSO asymmetry. For example, a key source of structural uncertainty in the ROM is whether drivers of ENSO asymmetry should be parameterized as stochastic or deterministic processes. In this work, we demonstrate how to (partially) sidestep this issue by treating SST and thermocline depth as observables of a dynamical system, rather than state variables, and modeling their evolution with the Koopman operator. While in both the ROM and the Koopman framework ENSO is represented by a single eigenmode, the Koopman eigenmode is a (learned) nonlinear function of the observables, permitting ENSO to evolve asymmetrically. We show that a simple model based on this eigenmode, analogous to the ROM, can capture many leading-order features of El Niño–La Niña asymmetry in the CESM2 preindustrial simulation, including the faster springtime decay of El Niños, the higher prevalence of multiyear La Niñas, and the westward displacement of anomalies during La Niñas. We anticipate this Koopman framework may be useful for studying intermodel differences in ENSO’s projected future changes, which are not well predicted by the ROM and appear related to climate models’ varied representation of ENSO asymmetry. Significance Statement El Niños tend to be more intense and shorter in duration than La Niñas. While many aspects of these events are well understood, the dominant causes of this asymmetry are not. In this study, we show how to incorporate asymmetry into an idealized model of ENSO by emulating its observed evolution, rather than attempting to simulate the underlying processes. Crucially, this framework does not require assumptions about which processes lead to asymmetry. This is advantageous, since the representation of these processes constitutes a major source of uncertainty in idealized models. We hence anticipate this framework may be useful for understanding El Niños’ projected future changes, which seem to depend strongly on the nonlinear processes giving rise to asymmetry in the present day.

中文摘要

摘要 ENSO的增长、衰减和位相转换机制由充放电振荡模型（ROM）描述，该模型由一组关于赤道海表温度（SST）和温跃层深度的耦合微分方程构成。尽管ROM能解释ENSO的许多关键特征，但由于对观测到的ENSO非对称性最重要的过程缺乏共识，其对非对称性的表征存在模糊性。例如，ROM中结构不确定性的一个关键来源是：ENSO非对称性的驱动因素应被参数化为随机过程还是确定性过程。在本研究中，我们通过将SST和温跃层深度视为动力系统的可观测量（而非状态变量），并利用Koopman算子建模其演化，展示了如何（部分）规避这一问题。在ROM和Koopman框架中，ENSO均由单一本征模态表示，但Koopman本征模态是可观测量的（学习得到的）非线性函数，从而允许ENSO非对称演化。我们证明，基于该本征模态的简单模型（类似于ROM）能够捕捉CESM2工业化前模拟中厄尔尼诺-拉尼娜非对称性的许多主要特征，包括厄尔尼诺春季衰减更快、多年拉尼娜事件更普遍，以及拉尼娜期间异常向西位移。我们预期这一Koopman框架可能有助于研究ENSO未来预估变化中的模式间差异——这些差异难以被ROM准确预测，且似乎与气候模式对ENSO非对称性的不同表征有关。
意义声明 厄尔尼诺事件通常比拉尼娜事件强度更大、持续时间更短。尽管这些事件的许多方面已被充分理解，但其非对称性的主导成因尚不明确。本研究表明，通过模拟ENSO的观测演化（而非尝试模拟其底层过程），可将非对称性纳入理想化ENSO模型。关键的是，该框架无需对导致非对称性的过程做出假设。这一优势显著，因为对这些过程的表征构成了理想化模型中不确定性的主要来源。因此，我们预期该框架可能有助于理解厄尔尼诺的未来预估变化——这些变化似乎强烈依赖于当前气候中产生非对称性的非线性过程。

35. JC — Changes in ENSO Oscillatory Dynamics Associated with Zonal Shifts in Air–Sea Coupling Region

Abstract

Abstract El Niño–Southern Oscillation (ENSO) oscillates between warm (El Niño) and cold (La Niña) phases, but observations indicate that this oscillatory behavior is irregular and asymmetric. Using the NCAR Community Earth System Model 1 (CESM), we investigate how the oscillatory dynamics of ENSO change across different climatic states. Our simulations of two glacial climates (Last Glacial Maximum, 21 ka; deglacial state, 15 ka), a preindustrial baseline (piControl), and two greenhouse warming scenarios (2xCO 2 ; 4xCO 2 ) reveal distinct dynamical regimes of oscillatory behavior driven by zonal shifts in air–sea coupling. Under preindustrial conditions, maximum wind–sea surface temperature coupling occurs near the Niño-3.4 region, and CESM reproduces the observed asymmetry of ENSO oscillatory behavior; El Niño events often rapidly decay into La Niña, while La Niña events rarely lead to El Niño but rather decay slowly back to neutral conditions. In simulated glacial climates, ENSO is nonoscillatory because the air–sea coupling region shifts westward of the Niño-3.4 region. In the western Pacific, a deeper thermocline weakens the delayed positive feedback needed for events to grow into the opposite phase, causing both El Niño and La Niña to decay back to neutral conditions. Conversely, in warmer climates, ENSO becomes more oscillatory and symmetric as the air–sea coupling region shifts eastward of the Niño-3.4 region. In the eastern Pacific, a shallower thermocline strengthens its positive feedback, enabling more frequent and consistent transitions between phases. This sensitivity of ENSO oscillatory behavior to the longitude of maximum air–sea coupling suggests that future changes in ENSO predictability in response to external forcings could be significant.

中文摘要

摘要 厄尔尼诺-南方涛动（ENSO）在暖位相（厄尔尼诺）和冷位相（拉尼娜）之间振荡，但观测表明这种振荡行为具有不规则性和不对称性。利用美国国家大气研究中心通用地球系统模式1（CESM），我们研究了ENSO振荡动力学如何随不同气候状态而变化。我们对两种冰期气候（末次盛冰期，21 ka；冰消期状态，15 ka）、一个工业化前基准态（piControl）以及两种温室增暖情景（2倍CO₂；4倍CO₂）的模拟揭示了由海气耦合经向位移驱动的不同振荡行为动力学机制。在工业化前条件下，最大风-海表温度耦合出现在尼诺-3.4区附近，CESM再现了ENSO振荡行为的观测不对称性：厄尔尼诺事件常迅速衰减为拉尼娜，而拉尼娜事件很少导致厄尔尼诺，而是缓慢衰减回中性状态。在模拟的冰期气候中，ENSO呈现非振荡特征，因为海气耦合区向西偏移至尼诺-3.4区以西。在西太平洋，较深的温跃层削弱了事件发展至相反位相所需的延迟正反馈，导致厄尔尼诺和拉尼娜均衰减回中性状态。相反，在较暖气候中，随着海气耦合区向东偏移至尼诺-3.4区以东，ENSO变得更具振荡性和对称性。在东太平洋，较浅的温跃层增强了其正反馈，使得位相转换更加频繁且一致。ENSO振荡行为对最大海气耦合经度的敏感性表明，未来ENSO可预报性对外部强迫的响应可能发生显著变化。

36. JC — Fueling the 2020–22 La Niña: The Role of Cross-Time-Scale Interference between the Indian Ocean Dipole and the Madden–Julian Oscillation

Abstract

Abstract Prior work suggests that the 2020–22 three-year-long La Niña event was triggered by the combination of a strong positive Indian Ocean dipole (IOD) event that began in 2019 and a strong Atlantic Niño; however, it is unclear what caused the positive IOD event. This analysis suggests that cross-time-scale interference between the IOD and Madden–Julian oscillation (MJO) contributed to the generation of this positive IOD event, with interactions occurring in two stages. First, during late April 2019, strong winds associated with MJO phases 2 and 3, and the related formation of two twin tropical cyclones, produced downwelling Kelvin waves in the Indian Ocean that propagated to the western coast of Java and Sumatra and reflected to the west as downwelling Rossby waves, subsequently deepening the thermocline in the eastern basin and triggering a weak positive IOD state. Within this weakly positive IOD state, a second MJO phase 2 and 3 event created additional westward-propagating downwelling Rossby waves that depressed the thermocline in the western basin, allowing for the progression of anomalous positive sea surface temperature anomalies toward the western part of the basin that triggered the strong positive IOD event. Based on these findings, and results from a linear wave model analysis, this study concludes that through cross-time-scale interference, the MJO preconditioned the positive IOD state during the first MJO event and contributed to the triggering of the strong positive IOD event during the second MJO occurrence. These combined mechanisms acted as a catalyst and contributed to the formation of the positive IOD event in 2019 that preceded the 3-yr-long La Niña event. Significance Statement The purpose of this study is to identify if two modes of climate variability—the Indian Ocean dipole and the Madden–Julian oscillation—interacted and contributed to the formation of the positive Indian Ocean dipole event observed during May–November 2019. Our results suggest that, in two stages, the Madden–Julian oscillation altered wind patterns and produced subsurface oceanic waves that impacted the Indian Ocean structure and led to the formation of the 2019 positive Indian Ocean dipole event. These findings are important because they help elucidate how the Indian Ocean dipole contributed to the 2020–22 La Niña event, which had influence on agriculture, water resources, and livelihoods around the world. Furthermore, the study sheds light on key interactions that state-of-the-art climate models must be able to reproduce to predict similar Indian Ocean dipole (IOD) events.

中文摘要

摘要：先前研究表明，2020–22年持续三年的拉尼娜事件是由2019年开始的强正印度洋偶极子（IOD）事件与强大西洋尼诺事件共同触发，但正IOD事件的成因尚不明确。本分析表明，IOD与马登-朱利安振荡（MJO）之间的跨时间尺度干扰促成了该正IOD事件的形成，其相互作用分为两个阶段。首先，2019年4月下旬，与MJO第2、3位相相关的强风及由此形成的两个双热带气旋，在印度洋产生向下传播的开尔文波，这些波传播至爪哇岛和苏门答腊岛西海岸后反射为向西传播的向下罗斯贝波，随后加深了东部海盆的温跃层，触发了弱正IOD状态。在此弱正IOD状态下，第二次MJO第2、3位相事件产生了额外的向西传播的向下罗斯贝波，这些波抑制了西部海盆的温跃层，使得异常正海表温度异常向西部海盆推进，从而触发了强正IOD事件。基于这些发现及线性波模式分析结果，本研究得出结论：通过跨时间尺度干扰，MJO在第一次MJO事件期间预置了正IOD状态，并在第二次MJO事件期间促成了强正IOD事件的触发。这些联合机制起到了催化剂作用，促成了2019年正IOD事件的形成，该事件先于持续三年的拉尼娜事件发生。意义声明：本研究旨在确定两种气候变率模态——印度洋偶极子与马登-朱利安振荡——是否相互作用并促成了2019年5–11月观测到的正印度洋偶极子事件。结果表明，马登-朱利安振荡通过两个阶段改变了风场并产生次表层海洋波，这些波影响了印度洋结构，最终导致2019年正印度洋偶极子事件的形成。这些发现具有重要意义，因为它们有助于阐明印度洋偶极子如何促成2020–22年拉尼娜事件，该事件对全球农业、水资源和生计产生了影响。此外，本研究揭示了关键相互作用机制，这些机制是当前最先进的气候模式必须能够再现的，以预测类似的印度洋偶极子（IOD）事件。

37. GRL — Propagating Internal‐Tide‐Induced Wave Stresses Resolve Discrepancies in Ocean Surface Tide Energetics

Abstract

Abstract Ocean tides are a major energy reservoir in Earth’s climate system, yet global tide models systematically fail to reproduce observed tidal energetics. This limitation arises because existing models do not adequately represent how tide‐generated internal waves in the deep ocean regulate ocean tide energy, accounting only for their initial generation and neglecting the wave stresses associated with their subsequent propagation. These wave stresses can be out of phase with the tidal flow and substantially modify tidal amplitudes. Here we explicitly represent these wave stresses in a global tide model and assess their impact on the energetics of global tides. We show that including these wave stresses is essential for reproducing observed tidal energetics and enables energetically consistent simulations even at coarse spatial resolution. These results highlight a previously missing physical process in tide models and facilitate more accurate and efficient modeling of global ocean tides.

中文摘要

摘要 海洋潮汐是地球气候系统中的主要能量库，然而全球潮汐模型系统性地未能再现观测到的潮汐能量学特征。这一局限性源于现有模型未能充分表征深海潮汐生成内波对潮汐能量的调控机制——它们仅考虑了内波的初始生成过程，却忽略了与其后续传播相关的波应力。这些波应力可能与潮汐流存在相位差，并显著改变潮汐振幅。本研究在全球潮汐模型中显式表征了这些波应力，并评估了其对全球潮汐能量学的影响。结果表明，纳入这些波应力对于再现观测到的潮汐能量学特征至关重要，即便在粗空间分辨率下也能实现能量一致的模拟。这些发现揭示了潮汐模型中此前缺失的物理过程，有助于实现更精确高效的全球海洋潮汐模拟。

38. GRL — A Sea Ice Entrapment Event in the Southern Chukchi Sea: Analysis and Prediction

  • 作者：G. W. K. Moore, Michael Steele, Jinlun Zhang, Axel Schweiger, Thomas J. Ballinger, Irina S. Trukhanova, Michael Lawson, William S. Beatty, Scott Hameister
  • 发表日期：2026-06-27
  • DOI：https://doi.org/10.1029/2025gl121181

Abstract

Abstract Amplified Arctic warming is reducing sea ice cover, which is driving an increase in geopolitical interest in the region as it offers the possibility of reducing shipping times between Asia, Europe, and eastern North America, at the risk of increased ice hazards. Here, we examine the case of the Norseman II research ship that was trapped by sea ice in the southern Chukchi Sea for 14 days in June 2024. This is the first study of its sort in this region. We show that anomalously thick and extensive sea ice was present north of the region prior to the event, and that strong northerly winds in early June advected this ice southward, trapping the ship. Later in June, southerly winds advected ice northwards away from the ship, helping to free it. We further show that the event was forecastable.

中文摘要

摘要 北极变暖加剧导致海冰覆盖减少，这引发了该地区地缘政治利益的增长，因为海冰减少为缩短亚洲、欧洲和北美东部之间的航运时间提供了可能，但同时也增加了冰害风险。本文研究了2024年6月“诺斯曼二号”研究船在楚科奇海南部被海冰围困14天的事件。这是该区域首次开展此类研究。我们表明，事件发生前该区域北部存在异常厚且范围广的海冰，而6月初的强北风将这片海冰向南输送，导致船只被困。6月下旬，南风将海冰向北吹离船只，帮助其脱困。我们进一步证明，该事件具有可预报性。

39. JC — Cross-Time-Scale Air–Sea Coupling in the Bering Sea

Abstract

Abstract Anomalous heat fluxes across the air–sea interface are a dominant driver of upper-ocean temperature variability in the Bering Sea. Atmospheric variability, specifically near-surface temperature, humidity, and wind, drives most of the ocean temperature response through modulation of the surface turbulent heat fluxes ( Q TH ). However, it remains unclear what atmospheric phenomena are responsible for the Q TH variability that regulates Bering Sea temperature. The objective of this work is to identify the time scales of air–sea coupling in the Bering Sea, which will improve understanding of the role of the atmosphere in regional ocean temperature trends and extremes. Using fifth generation European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalysis (ERA5) fields, we show that anomalous surface sensible ( Q SH ) and latent ( Q LH ) heat fluxes over the Bering Sea are strongly coupled to anomalous large-scale meridional advection of heat and moisture by the atmosphere and that the canonical view that storms drive regional surface turbulent flux variability is incomplete. Through a new application of bispectral analysis, we show evidence of cross-time-scale coupling in Q SH and Q LH and their associated atmospheric circulation. Elevated bicoherence between the low-frequency annual cycle and a broad band of higher frequencies indicates a pathway of interaction in which phenomena that vary on a specific time scale can manifest as variability occurring on a different time scale. The results of this analysis limit the candidate mechanisms that drive Bering Sea thermal variability through their modulation of surface turbulent heat exchange to those with a strong intraseasonal component and/or cross-frequency interactions. Significance Statement Anomalies in the exchange of heat between the ocean and atmosphere are the dominant driver of Bering Sea temperature variability, and these anomalies are primarily a result of wind direction and of atmospheric temperature and humidity anomalies. However, the atmospheric phenomena that are responsible for the passage of these airmass anomalies over the Bering Sea are unknown. In this work, we show that the anomalous surface heat fluxes are strongly coupled with large-scale meridional transport of heat and moisture by the atmosphere; however, contrary to general understanding, high-frequency atmospheric variability, including storms, is not the primary atmospheric phenomena responsible for this variability in meridional transport. We then show that phenomena that vary on specific time scales can be coupled with variability on different time scales in surprising ways, which complicates the identification of atmospheric circulation patterns driving the Bering Sea temperature response.

中文摘要

摘要 海气界面异常热通量是白令海上层海洋温度变化的主要驱动因素。大气变率，特别是近地表温度、湿度和风，通过调节地表湍流热通量（QTH）驱动了大部分海洋温度响应。然而，目前尚不清楚何种大气现象导致了调控白令海温度的QTH变率。本研究旨在识别白令海海气耦合的时间尺度，这将有助于理解大气在区域海洋温度趋势和极端事件中的作用。利用欧洲中期天气预报中心（ECMWF）第五代大气再分析（ERA5）资料，我们发现白令海异常地表感热通量（QSH）和潜热通量（QLH）与大气异常大尺度经向热量和水汽平流存在强耦合，而风暴驱动区域地表湍流通量变率的经典观点并不完整。通过双谱分析的新应用，我们展示了QSH和QLH及其相关大气环流中存在跨时间尺度耦合的证据。低频年循环与较宽高频带之间的高双相干性表明存在一种相互作用路径，其中特定时间尺度变化的现象可表现为不同时间尺度上的变率。本分析结果将驱动白令海热力变率的候选机制限制为那些具有强季节内成分和/或跨频率相互作用的机制，这些机制通过调节地表湍流热交换发挥作用。意义声明 海洋与大气之间的异常热交换是白令海温度变化的主要驱动因素，这些异常主要源于风向以及大气温度和湿度异常。然而，导致这些气团异常经过白令海的大气现象尚不明确。本研究表明，异常地表热通量与大气大尺度经向热量和水汽输送存在强耦合；但与普遍认知相反，包括风暴在内的高频大气变率并非导致这种经向输送变率的主要大气现象。我们进一步发现，特定时间尺度变化的现象可能以令人意外的方式与不同时间尺度的变率耦合，这使识别驱动白令海温度响应的大气环流模式变得复杂。

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。

  • GRL — Marine Phytoplankton Extremes and Compound Extreme Events Have the Potential to Be Predicted Multiple Months in Advance（DOI: https://doi.org/10.1029/2026gl121872）
    • 命中: ocean stratification, marine heatwave
    • 排除: phytoplankton
  • GRL — Winter Storm Induced Turbulent Structure Alteration Triggers Sediment Export From an Abandoned Subaqueous Delta（DOI: https://doi.org/10.1029/2025gl119802）
    • 命中: turbulence
    • 排除: sediment
  • GRL — High‐Resolution Tomography for the Upper‐Mantle Structure in North China by Full‐Waveform Inversion of Teleseismic P Wave and Its Codas（DOI: https://doi.org/10.1029/2025gl120963）
    • 命中: upwelling
    • 排除: seismic
  • JC — Large-Scale Climate Drivers of the Interannual Variability of Marine Heat Waves in the Western North Pacific and Its Marginal Seas（DOI: https://doi.org/10.1175/jcli-d-25-0390.1）
    • 命中: Kuroshio, thermocline, eddies, entrainment, sea surface temperature
    • 排除: biodiversity

待人工核实

元数据缺失（摘要 / DOI / 作者），需人工核查后再纳入。

  • JGR: Oceans — Issue Information
    • 缺失项: 摘要缺失或过短; 作者列表缺失
    • 链接: https://doi.org/10.1029/jgrc.70247
  • Ocean Modelling — Evaluation of the third-generation Typhoon model in the Northwest Pacific operational forecasting for 2023
    • 缺失项: 摘要缺失或过短
    • 链接: https://doi.org/10.1016/j.ocemod.2026.102791
  • Ocean Modelling — Influence of typhoon on upwelling dynamics over a coastal valley in the northwestern Taiwan strait
    • 缺失项: 摘要缺失或过短
    • 链接: https://doi.org/10.1016/j.ocemod.2026.102788
  • Ocean Modelling — Detection of surface submesoscale fronts in the Atlantic Ocean
    • 缺失项: 摘要缺失或过短
    • 链接: https://doi.org/10.1016/j.ocemod.2026.102787
  • JPO — Journal Information and Table of Contents
    • 缺失项: 摘要缺失或过短; 作者列表缺失
    • 链接: https://doi.org/10.1175/jpo-567cover