本期覆盖 2026-08-07 至 2026-08-14，共收录高置信度文章 15 篇，边缘相关 1 篇，待人工核实 0 篇。

本周亮点

亮点 1：Planetary energy budget during abrupt glacial climate events set by Atlantic Ocean heat valve

期刊：Nature Geoscience ｜ DOI：https://doi.org/10.1038/s41561-026-02070-6

English summary

This study synthesizes simulations to show that variations in Atlantic Meridional Overturning Circulation strength during abrupt Dansgaard–Oeschger events controlled ocean heat content and planetary heat uptake. The findings highlight the Atlantic Ocean’s role as a heat valve in setting the planetary energy budget during glacial climate events. This work provides a mechanistic link between ocean circulation and global climate variability on millennial timescales.

中文解读

该研究综合模拟结果，表明在末次冰期突然的丹斯高-厄施格事件期间，大西洋经向翻转环流强度的变化控制了海洋热含量和全球热量吸收。研究结果凸显了大西洋作为热阀在冰期气候事件中调节行星能量收支的作用。该工作为海洋环流与全球气候在千年尺度上的变率提供了机制联系。

亮点 2：Failure to track a stable AMOC state under rapid climate change

期刊：Nature Climate Change ｜ DOI：https://doi.org/10.1038/s41558-026-02730-w

English summary

This work demonstrates that the stability of the Atlantic Meridional Overturning Circulation (AMOC) depends on the rate of atmospheric CO2 change rather than having a fixed threshold. Under rapid climate change, the AMOC may fail to track a stable state, implying that collapse risks are more dynamic than previously thought. This challenges traditional tipping point concepts and has significant implications for climate projections.

中文解读

该研究表明，大西洋经向翻转环流（AMOC）的稳定性取决于大气CO2变化的速率，而非固定的阈值。在快速气候变化下，AMOC可能无法追踪稳定状态，这意味着其崩溃风险比以往认为的更具动态性。这一发现挑战了传统的临界点概念，对气候预测具有重要意义。

文章详览

1. JPO — Gradient Wind-Balanced Subsurface Anticyclonic Eddies Offshore Southern Chile

Abstract

Abstract Subsurface eddies are a key component of eastern boundary upwelling systems, yet their structure and dynamics remain poorly constrained by observations. Using multichannel seismic reflection data combined with simultaneous shipboard ADCP measurements, we investigate two subsurface submesoscale anticyclonic eddies observed offshore of southern Chile in February 2017. Seismic imaging provides high-resolution constraints on the vertical structure and horizontal scales of the eddies, particularly their lateral boundaries. Based on the eddy geometry resolved from seismic imaging and coincident velocity observations, we conduct quantitative analyses of the eddy velocity structure and momentum balance. The estimated Rossby numbers indicate strongly ageostrophic dynamics, and a comparison of centrifugal and Coriolis terms shows that the radial momentum balance of both eddies is governed by gradient wind balance rather than geostrophic balance. The joint observations further reveal a strong poleward Peru-Chile Undercurrent (PCUC) near 44°S, with velocities of 0.1-0.2 m s −1 , characterized by a distinctive seismic reflection signature along the continental slope. The spatial relationship among the eddies, the undercurrent, and local bathymetric curvature provides new observational evidence that subsurface anticyclonic eddies in eastern boundary upwelling systems can form through flow separation of the poleward undercurrent. These results demonstrate the value of combining seismic oceanography with velocity measurements to constrain the dynamics of subsurface submesoscale eddies.

中文摘要

摘要 次表层涡旋是东部边界上升流系统的关键组成部分，然而其结构和动力学特性仍受观测限制而了解不足。利用多道地震反射数据结合同步的船载ADCP测量，我们研究了2017年2月在智利南部近海观测到的两个次表层次中尺度反气旋涡旋。地震成像提供了对涡旋垂直结构和水平尺度的高分辨率约束，尤其是其侧向边界。基于地震成像解析的涡旋几何形态及同步速度观测，我们对涡旋速度结构和动量平衡进行了定量分析。估算的罗斯比数表明存在强烈的非地转动力学特征，离心力与科氏力的比较显示，两个涡旋的径向动量平衡由梯度风平衡而非地转平衡主导。联合观测还揭示了在44°S附近存在一股强劲的向极秘鲁-智利潜流（PCUC），流速为0.1-0.2米/秒，其特征是沿大陆坡具有独特的地震反射信号。涡旋、潜流与局部海底地形曲率之间的空间关系提供了新的观测证据，表明东部边界上升流系统中的次表层反气旋涡旋可通过向极潜流的流动分离形成。这些结果展示了将地震海洋学与速度测量相结合以约束次表层次中尺度涡旋动力学的价值。

2. JPO — Barotropic to baroclinic transition in tidal flows

Abstract

Abstract As the ocean tide flows over the rough seafloor it induces topographic stresses that feed back on the strength of the tide. Here we examine how these topographic stresses change as the dynamical regime transitions from barotropic to baroclinic with increasing stratification and/or decreasing topographic lengthscale, thereby bridging between previous work which studied one or other regime in isolation. Our investigation is conducted using linear theory validated by comparison with a suite of over 100 fully nonlinear numerical simulations. For super-inertial tidal flows across an isolated ridge, it is shown that the topographic stress rapidly transitions from out-of-phase with the tidal flow to in-phase with the tidal flow at ridge widths of 1-2 times the baroclinic mode-1 wavelength. This change in stress is associated with a switch from topographically-confined perturbation flows in the barotropic regime to radiating waves in the baroclinic regime. The transition becomes more complicated in the presence of multiple ridges due to the interference of the waves generated at each. These interactions lead to significant changes in both the magnitude and phase of the topographic stress as compared to the sum of the contributions from two isolated ridges. Further, particular combinations of ridges — so-called ‘invisible topographies’ — lead to exactly zero stress and therefore have no effect on the barotropic tide. These results have implications for improving models of ocean tides and tidally-driven mixing.

中文摘要

摘要 当海洋潮汐流经粗糙海床时，会诱发地形应力，进而反馈影响潮汐强度。本文探讨了随着层化增强和/或地形长度尺度减小，动力机制从正压向斜压转变时，这些地形应力如何变化，从而桥接了以往分别研究单一机制的工作。我们采用线性理论，并通过与超过100次全非线性数值模拟结果的对比验证。对于跨越孤立海脊的超惯性潮汐流，研究表明，当地形应力在海脊宽度为斜压第一模态波长的1-2倍时，迅速从与潮汐流异相转变为同相。这种应力变化与扰动流从正压 regime 中的地形受限流转变为斜压 regime 中的辐射波相关联。在存在多个海脊的情况下，由于各海脊产生的波相互干涉，这一转变变得更加复杂。与两个孤立海脊贡献之和相比，这些相互作用导致地形应力的大小和相位发生显著变化。此外，特定的海脊组合——所谓的“隐形地形”——会导致应力恰好为零，因此对正压潮汐无影响。这些结果对改进海洋潮汐及潮致混合模型具有重要意义。

3. JPO — Meso- and Sub-mesoscale Wind–Front Interactions and Their Impacts on Ocean Vertical Velocities

Abstract

Abstract Coherent surface ocean temperature and velocity structures, with scales spanning 10–100 km, induce surface wind stress anomalies that generate near-surface vertical velocities through Ekman dynamics. These wind–front interactions are known as Thermal (TFB) and Current (CFB) feedbacks. Their relative contributions to ocean vertical velocities and their variability across scales remain underexplored. This study decomposes and attributes Ekman vertical velocity variability to TFB and CFB at O (100) km and O (10) km scales using output from a global 4–6 km ocean–atmosphere coupled simulation, focusing on the California Current System. Total Ekman velocities are decomposed into a linear component associated with wind stress curl and a nonlinear component involving ocean vorticity derivatives. At 30–200 km scales, TFB and CFB contribute similarly to the linear component, which is comparable in magnitude to the nonlinear term ( O (1–5) m day −1 in instantaneous value). At <30 km scales, nonlinear Ekman velocities exceed linear terms by an order of magnitude, reaching instantaneous values of O (10–50) m day −1 and matching the total near-surface vertical velocities. The decomposition reveals that the nonlinear enhancement is driven by ocean vorticity gradients at <30 km scales. These results emphasize the importance of resolving small-scale wind–front interactions and ocean surface features that modulate upper-ocean vertical velocities, demonstrating, as a first step, the potential to infer subsurface vertical motions from surface measurements and Ekman dynamics. However, such inferences should be interpreted with caution where the surface Rossby number exceeds unity.

中文摘要

摘要 海表温度和流速的相干结构，其尺度跨越10–100公里，会引发海面风应力异常，进而通过埃克曼动力学产生近表层垂直速度。这些风与锋面的相互作用被称为热力反馈（TFB）和动力反馈（CFB）。它们对海洋垂直速度的相对贡献及其在不同尺度上的变化尚未得到充分探索。本研究利用全球4–6公里分辨率的海气耦合模拟输出，聚焦加利福尼亚海流系统，在O（100）公里和O（10）公里尺度上分解并归因埃克曼垂直速度的变率至TFB和CFB。总埃克曼速度被分解为与风应力旋度相关的线性分量和涉及海洋涡度导数的非线性分量。在30–200公里尺度上，TFB和CFB对线性分量的贡献相似，其量级与非线性项相当（瞬时值约为O（1–5）米/天）。在小于30公里尺度上，非线性埃克曼速度超过线性项一个数量级，瞬时值达到O（10–50）米/天，并与总近表层垂直速度相匹配。分解结果表明，非线性增强由小于30公里尺度上的海洋涡度梯度驱动。这些结果强调了解析小尺度风-锋面相互作用和调节上层海洋垂直速度的海表特征的重要性，初步展示了从海表测量和埃克曼动力学推断次表层垂直运动的潜力。然而，在海表罗斯比数超过1的区域，此类推断应谨慎解读。

4. JC — IOD-induced Gill-pattern winds determine the interannual variability of southwestern monsoon current axis in the southern Bay of Bengal

Abstract

Abstract The southwestern monsoon current (SMC) flowing from the Arabian Sea (AS) into the Bay of Bengal (BoB), driven by summer monsoon, can significantly affect the thermohaline structure of the BoB and further influence summer monsoon variability through air-sea interaction. The SMC exhibited significant interannual variability, especially in its axis position during 1993–2022. Analysis reveals that the interannual variability of the SMC axis position is mainly related to the Indian Ocean Dipole (IOD) and its induced Ekman effect, which is forced by local wind stress curl (WSC) in the southern BoB. A positive (negative) IOD triggers a Gill-pattern response in the eastern Indian Ocean, as well as an anomalous anticyclonic (cyclonic) circulation over the BoB and an easterly (westerly) wind anomaly across the equatorial Indian Ocean from June to September. The SMC axis migrates northward (southward) when there is a negative (positive) local WSC in the southern BoB during positive (negative) IOD, which leads to positive (negative) sea surface height anomalies (SSHA), and hence the maximum meridional SSHA gradient shifts northward (southward). The influence of the equatorial wind anomaly on the SMC axis is weaker than the Ekman effects of the local wind anomaly in the southern BoB, but opposite in direction. The counteraction between the eastern boundary-reflected Rossby waves and the local negative (positive) wind stress curl forcing induced by a positive (negative) IOD is quantitatively confirmed by analyzing vorticity balance and wind forcing over southern BoB using the vorticity budget and the 1.5-layer reduced-gravity model.

中文摘要

摘要 西南季风气流（SMC）自阿拉伯海（AS）流入孟加拉湾（BoB），受夏季季风驱动，能显著影响孟加拉湾的温盐结构，并通过海气相互作用进一步影响夏季季风变率。1993—2022年间，SMC表现出显著的年际变率，尤其是其轴线位置的变化。分析表明，SMC轴线位置的年际变率主要与印度洋偶极子（IOD）及其引发的埃克曼效应有关，该效应由孟加拉湾南部的局地风应力旋度（WSC）所驱动。正（负）IOD在东印度洋触发吉尔型响应，并在孟加拉湾上空形成异常反气旋（气旋）环流，同时自6月至9月在赤道印度洋产生东风（西风）异常。当正（负）IOD期间孟加拉湾南部存在负（正）局地WSC时，SMC轴线向北（南）迁移，导致海表面高度异常（SSHA）为正（负），进而使经向SSHA梯度最大值位置北（南）移。赤道风异常对SMC轴线的影响弱于孟加拉湾南部局地风异常的埃克曼效应，但方向相反。通过涡度收支和1.5层约化重力模型对孟加拉湾南部的涡度平衡及风强迫进行分析，定量证实了由正（负）IOD引起的东边界反射罗斯贝波与局地负（正）风应力旋度强迫之间的相互抵消作用。

5. JC — Horseshoe Salinity Pattern in the Upper Indian Ocean and its Decadal Variability

Abstract

Abstract Salinity plays a crucial role in the global hydrological cycle and climate system by regulating upper ocean stratification and sea surface temperature (SST). Past studies have revealed the dynamics of salinity variation in the world’s major ocean basins and its linkage to global climate on interannual to decadal time scales. However, understanding of upper ocean salinity variability in the Indian Ocean, especially on decadal time scale and its global implications, remains limited. This study identifies a prominent Horseshoe Salinity Pattern (HSP), present in the Indian Ocean, extending from surface to 150m depth. It exhibits pronounced decadal variability and is closely associated with SST variability in the southeastern Indian Ocean (SEIO) with a lag of ∼18 months. Composite maps and a sea surface salinity budget analysis reveal that SST anomalies in the SEIO region modulate the local Walker and Hadley circulation anomaly causing the variation in the precipitation pattern. These changes drive upper ocean freshening or salinification, producing the observed HSP. Advection contributes regionally to salinity variability, particularly in the southern Indian Ocean, but does not play a dominant role in shaping the coherent HSP structure. Further, this pattern modulates upper-ocean stratification, leading to the development of SST anomalies in the western tropical Indian Ocean. These findings offer novel insight into the Indian Ocean salinity dynamics, highlighting the role of SST-salinity coupling and have the potential for improving predictions of decadal climate variability and its global implications.

中文摘要

摘要 盐度通过调节上层海洋层结和海表温度（SST），在全球水文循环和气候系统中发挥着关键作用。以往研究揭示了世界主要大洋盆地盐度变化的动力学及其在年际至年代际时间尺度上与全球气候的联系。然而，对印度洋上层海洋盐度变率，尤其是年代际尺度及其全球影响的理解仍然有限。本研究识别出印度洋中存在一种显著的马蹄形盐度模式（HSP），该模式从海表延伸至150米深度，表现出明显的年代际变率，并与东南印度洋（SEIO）的海表温度变率密切相关，滞后约18个月。合成图和海表盐度收支分析表明，SEIO区域的海表温度异常调节了局地Walker和Hadley环流异常，导致降水模式的变化。这些变化驱动上层海洋的淡化或咸化，从而产生观测到的HSP。平流在区域上对盐度变率有所贡献，尤其是在南印度洋，但在塑造连贯的HSP结构中并未起主导作用。此外，该模式调节上层海洋层结，导致热带西印度洋海表温度异常的发展。这些发现为印度洋盐度动力学提供了新的见解，强调了海表温度-盐度耦合的作用，并有望改进年代际气候变率及其全球影响的预测。

6. JC — Tropical Teleconnection Influences on Decadal Trends in West Antarctic Surface Mass Balance

Abstract

Abstract The surface mass balance (SMB) of the Antarctic Ice Sheet is a critical factor in influencing global mean sea level rise and has substantial implications for future projections of sea level rise. In recent decades, the Antarctic Ice Sheet SMB trends show pronounced regional disparities, marked by a decrease over the western part but an increase over the eastern part of West Antarctica. Through a synthesis of ice core records and five reanalysis datasets, as well as atmospheric dynamics analysis and numerical model simulations, we demonstrate that the multi-decadal trends in tropical sea surface temperature are key drivers of the dipole-like SMB trends in West Antarctica. Specifically, the eastern tropical Pacific cooling associated with the phase changes of the Interdecadal Pacific Oscillation (IPO) and the tropical Atlantic warming associated with the Atlantic Multi-decadal Oscillation (AMO) can modulate tropical convection and latent-heating anomalies, thereby stimulating Rossby wave trains propagating to the West Antarctic, resulting in the contrasting moisture divergence and precipitation changes between the western and eastern parts of West Antarctica. In particular, the statistical analysis and model simulation clarify the seasonality of these teleconnections. Both the Pacific and Atlantic contribute to the dipole-like SMB pattern during austral spring and autumn, while the Pacific is the major contributor during austral summer. Our findings have broad implications for understanding the recent observed SMB trends as well as future projections of Antarctic SMB changes and consequent global sea level rise.

中文摘要

南极冰盖的表面物质平衡（SMB）是影响全球平均海平面上升的关键因素，对未来海平面上升的预估具有重要影响。近几十年来，南极冰盖SMB趋势显示出显著的区域差异，表现为南极西部冰盖西部减少而东部增加的特征。通过综合冰芯记录与五套再分析资料，结合大气动力学分析和数值模式模拟，我们证明热带海表温度的多年代际趋势是南极西部偶极型SMB趋势的关键驱动因素。具体而言，与太平洋年代际振荡（IPO）位相变化相关的东热带太平洋冷却，以及与大西洋多年代际振荡（AMO）相关的热带大西洋增暖，能够调节热带对流和潜热异常，从而激发传播至南极西部的罗斯贝波列，导致南极西部冰盖西部与东部之间水汽辐散和降水变化的对比性差异。特别地，统计分析和模式模拟阐明了这些遥相关的季节性特征。太平洋和大西洋共同贡献于南极春季和秋季的偶极型SMB模式，而太平洋则是南极夏季的主要贡献者。我们的发现对于理解近期观测到的SMB趋势以及未来南极SMB变化及其引发的全球海平面上升预估具有广泛意义。

7. GRL — Weak Tropical Tropospheric OH Response to Idealized ENSO

Abstract

Abstract The hydroxyl radical (OH) is a key oxidant for methane. Previous studies suggest that OH exhibits interannual variability linked to the El Nino–Southern Oscillation (ENSO), but the sign, magnitude, and underlying mechanisms of this response remain uncertain. We diagnose changes in OH using the CAM‐chem chemistry–climate model with prescribed sea surface temperature composites corresponding to ENSO phases. We find a weak but statistically significant 2.3% decrease in tropical tropospheric air‐mass‐weighted OH during El Nino, and no significant change during La Nina. During El Nino, this net decline in OH is driven by enhanced biogenic and biomass burning emissions, while the direct meteorological contribution is negligible. Lightning‐produced NO emissions and their associated effects on OH are indistinguishable from atmospheric variability during both ENSO phases. Our results indicate that biogenic emissions play a significant but previously underappreciated role in regulating interannual variability in OH and the global methane budget.

中文摘要

摘要 羟基自由基（OH）是甲烷的关键氧化剂。以往研究表明，OH表现出与厄尔尼诺-南方涛动（ENSO）相关的年际变率，但这一响应的符号、幅度及其潜在机制仍不确定。我们利用CAM-chem化学-气候模式，通过指定与ENSO相位对应的海表温度合成场，诊断了OH的变化。研究发现，在厄尔尼诺期间，热带对流层空气质量加权OH浓度出现微弱但统计显著的2.3%下降，而在拉尼娜期间则无显著变化。在厄尔尼诺期间，这一OH净减少主要由增强的生物源和生物质燃烧排放驱动，而直接气象贡献可忽略不计。闪电产生的氮氧化物排放及其对OH的相关影响，在两种ENSO相位下均与大气变率难以区分。我们的结果表明，生物源排放在调节OH年际变率及全球甲烷收支中发挥着重要作用，但这一作用此前未得到充分认识。

8. GRL — Seal‐Based Detection of Southward Intrusion of mCDW on the Ross Sea Continental Shelf

  • 作者：Hyunjae Chung, Jikang Park, Mijin Park, Yejin Kim, Unyoung Chun, Sukyoung Yun, Won Sang Lee, Won Sang Lee, Hyun A. Choi, Craig Stevens, Seung-Tae Yoon, Ji Sung Na, Won Sang Lee, Won Sang Lee
  • 发表日期：2026-08-12
  • DOI：https://doi.org/10.1029/2025gl119774

Abstract

Abstract Seasonal exchange between modified Circumpolar Deep Water (mCDW) and dense shelf water shapes Antarctic Bottom Water in the Ross Sea, making year‐round hydrographic observations indispensable, yet winter observations remain scarce. Miniaturized CTD tags deployed on 64 Weddell seals in Terra Nova Bay during three years relayed 22,661 profiles across the shelf, supplemented by 43 ship‐based CTD profiles. To characterize vertically structured and spatially irregular hydrographic observations, CTD profiles were reduced with principal component analysis and clustered using Gaussian‐mixture models, performed separately for summer and winter. Summer is characterized by stratification and mid‐depth mCDW intrusions, whereas winter reveals multiple mCDW regimes, including warm, salty inflows along troughs, fresher intrusions near Hayes Bank, and mCDW–HSSW mixed layer. These results demonstrate that, contrary to previous studies suggesting mCDW influence is confined to summer, mCDW also penetrates onto the shelf during winter, where its interaction with dense shelf waters defines distinct transformation zones.

中文摘要

摘要 季节性的改良绕极深层水（mCDW）与密集陆架水之间的交换塑造了罗斯海南极底层水的特性，这使得全年水文观测不可或缺，然而冬季观测数据仍然稀缺。在三年间，部署于特拉诺瓦湾64只威德尔海豹身上的微型CTD标签回传了22,661个陆架剖面，辅以43个船基CTD剖面。为刻画垂直结构化和空间不规则的水文观测数据，CTD剖面通过主成分分析降维，并利用高斯混合模型进行聚类，分别针对夏季和冬季进行。夏季以层化和中层mCDW入侵为特征，而冬季则揭示了多种mCDW状态，包括沿海槽的暖咸流入、海斯浅滩附近的较淡入侵，以及mCDW与高盐陆架水混合层。这些结果表明，与先前认为mCDW影响仅限于夏季的研究相反，mCDW在冬季也能渗透至陆架，其与密集陆架水的相互作用定义了不同的转变区域。

9. GRL — Positive Association Between Coastal Sea Surface Temperatures and Humid Heat Stress on Nearby Land

Abstract

Abstract Large populations along Earth’s coastlines are exposed to climate hazards including extreme humid heat. Considering observed coastal ocean warming and increased coastal marine heatwave (MHW) activity, we seek to uncover if, how, and where coastal ocean temperatures are linked with heat and humidity on land nearby. We analyze near‐coastal sea surface temperatures (SST) and corresponding land heat characteristics at 1,474 global coastal locations from 1990 to 2023 and find coastal MHW occurrence is associated with positive terrestrial heat/humidity anomalies across seasons, and that warmer coastal SST are associated with more frequent hot/humid extremes on land. We highlight an increase in concurrent marine and terrestrial (THW) heatwave days at many locations, which appears largely driven by MHW trends. Coastal MHW, THW, and concurrent events share similar buildup characteristics, but concurrent and MHW events are more humid than THW and display temperature anomalies which peak at the surface rather than aloft.

中文摘要

摘要 地球海岸沿线的大量人口正面临包括极端湿热在内的气候灾害。鉴于观测到的沿海海洋变暖及海洋热浪（MHW）活动的增加，我们旨在揭示沿海海洋温度是否、如何以及在何处与邻近陆地的热量和湿度相关联。我们分析了1990年至2023年间全球1,474个沿海地点的近岸海表温度（SST）及相应的陆地热特征，发现沿海MHW的发生与跨季节的陆地正热/湿度异常相关，且较暖的沿海SST与陆地上更频繁的炎热/潮湿极端事件相关联。我们强调，在许多地点，海洋与陆地热浪（THW）同时发生的天数有所增加，这似乎主要由MHW趋势驱动。沿海MHW、THW及同时发生的事件具有相似的积聚特征，但同时发生的事件和MHW事件比THW更潮湿，且其温度异常在地表达到峰值而非高空。

10. GRL — Anomalous Sea Ice Retreat in the Refreezing Western Arctic by a 30‐Year Record Cyclone in October: Oceanic, Atmospheric, and Wave Influences

Abstract

Abstract An extreme Arctic cyclone (AC) in October 2022 reached a record‐low pressure of 955 hPa and caused unusual wave‐induced sea‐ice breakup in the Canada Basin, making it the strongest event in the western Arctic in 30 years. Here we examine how this event interrupted freeze‐up by quantifying sea‐ice retreat associated with atmospheric and oceanic thermodynamic anomalies, focusing on positive surface energy balance (SEB) anomalies and enhanced ocean heat content (OHC). Using a latent heat of fusion framework, we estimate melt‐equivalent sea‐ice thickness (SIT) reductions from anomalous SEB and OHC. Oceanic thermodynamics may cause up to 14 cm of upper‐bound SIT potential reductions, exceeding the atmospheric contribution of 1 cm. Atmospheric forcing peaked 1 day before the cyclone maximum, whereas oceanic forcing peaked at the storm peak. The discrepancy between thermodynamic estimates and observed ice‐cover changes suggests that mechanical redistribution and wave‐induced fragmentation may have delayed freeze‐up and enhanced open‐water exposure.

中文摘要

摘要 2022年10月一次极端北极气旋（AC）达到了创纪录的955百帕低气压，并在加拿大海盆引发了异常的海浪致海冰破裂事件，使其成为30年来西北极最强的一次气旋事件。本文通过量化与大气和海洋热力学异常相关的海冰退缩，重点研究正地表能量平衡（SEB）异常和增强的海洋热含量（OHC），探讨了这一事件如何中断冻结过程。利用潜热融解框架，我们估算了由异常SEB和OHC引起的融等效海冰厚度（SIT）减少量。海洋热力学过程可能导致高达14厘米的上限SIT潜在减少，超过大气贡献的1厘米。大气强迫在气旋最强前1天达到峰值，而海洋强迫在风暴峰值时达到峰值。热力学估算与观测到的冰覆盖变化之间的差异表明，机械再分布和波浪诱导的碎裂可能延迟了冻结过程，并增加了开阔水域的暴露。

11. GRL — Transition of Turbulence Features From Frontal Modulation to Typhoon Forcing Over the Northern South China Sea Shelf

Abstract

Abstract Ocean turbulence, crucial for regulating Earth systems, is substantially modulated by background dynamic processes. Using 8‐day‐long hourly microstructure observations over the South China Sea shelf in summer, we investigate turbulence evolution under strong stratification and successively modulated by a front and a typhoon. In the mixed layer, the front sustains strong stratification and inhibits shear and convective instabilities, suppressing turbulence and causing low eddy diffusivity K θ and mixing efficiency Γ. Sporadic intensified subsurface mixing couples with surface‐heating‐induced sharp temperature gradient and elevates daytime Γ throughout the thermocline. Typhoon and subsequent storms then drastically weaken stratification, promote convective instability, and elevate turbulence intensity, K θ and Γ greatly. The thermocline remains strongly stratified, suppressing turbulence and causing weak dissipation and mixing. Thermocline‐Γ stays low mostly, then rises markedly once near‐inertial waves emerge, averaging 0.15. Scaling of Thermocline‐Γ based on buoyancy Reynolds number Re b and turbulent Froude number Fr t suggests Γ∝ Re b −1/4 Fr t 0 .

中文摘要

摘要 海洋湍流对调节地球系统至关重要，其受到背景动力过程的显著调制。利用南海陆架夏季为期8天的逐时微结构观测数据，我们研究了在强层结条件下，依次受锋面和台风调制下的湍流演变过程。在混合层内，锋面维持强层结，抑制剪切和对流不稳定性，从而压制湍流，导致低涡扩散系数Kθ和混合效率Γ。零星增强的次表层混合与表面加热引起的陡峭温度梯度耦合，提高了整个温跃层白天的Γ值。随后台风及后续风暴大幅削弱层结，促进对流不稳定性，并显著提升湍流强度、Kθ和Γ。温跃层保持强层结，抑制湍流，导致弱耗散和混合。温跃层Γ值大多保持较低，一旦近惯性波出现则显著上升，平均值为0.15。基于浮力雷诺数Reb和湍流弗劳德数Frt的温跃层Γ尺度化表明Γ∝Reb−1/4Frt0。

12. Nature Geoscience — Planetary energy budget during abrupt glacial climate events set by Atlantic Ocean heat valve

  • 作者：Christo Buizert, Ayako Abe-Ouchi, Guido Vettoretti, Xu Zhang, Yuta Kuniyoshi, Sarah Shackleton, Sune Olander Rasmussen, Joel B. Pedro, Eric D. Galbraith, Thomas F. Stocker
  • 发表日期：2026-08-10
  • DOI：https://doi.org/10.1038/s41561-026-02070-6

Abstract

Nature Geoscience, Published online: 10 August 2026; doi:10.1038/s41561-026-02070-6 Variations in Atlantic Meridional Overturning Circulation strength through abrupt Dansgaard–Oeschger events during Pleistocene glacial periods controlled ocean heat content, and heat uptake by the planet as a whole, according to a synthesis of simulations.

中文摘要

《自然·地球科学》，在线发表于2026年8月10日；doi:10.1038/s41561-026-02070-6 根据模拟综合研究，更新世冰期期间，通过 abrupt Dansgaard–Oeschger 事件的大西洋经向翻转环流强度变化，控制了海洋热含量以及整个地球的热量吸收。

13. Nature Climate Change — Failure to track a stable AMOC state under rapid climate change

Abstract

Nature Climate Change, Published online: 13 August 2026; doi:10.1038/s41558-026-02730-w Climate change is expected to alter oceanic circulation, with the Atlantic Meridional Overturning Circulation (AMOC) at risk of collapse. This work shows that the stability of the AMOC is dependent on the rate of atmospheric CO2 change rather than having a fixed threshold.

中文摘要

《自然·气候变化》，在线发表于2026年8月13日；doi:10.1038/s41558-026-02730-w 预计气候变化将改变海洋环流，其中大西洋经向翻转环流（AMOC）面临崩溃风险。本研究表明，AMOC的稳定性取决于大气CO2变化速率，而非具有固定阈值。

14. GRL — Quantifying Daily Vertical Heat Flux in the Loop Current System: A Quasi‐Lagrangian Assessment of Frontal Hotspots

Abstract

Abstract Vertical heat exchange within the upper ocean critically influences regional climate but remains difficult to observe directly. In the Gulf of Mexico, the Loop Current and its associated eddies significantly enhance this exchange. High‐resolution glider observations reveal that this transport is dominated by sub‐daily variability an order of magnitude greater than background conditions. When the glider trajectory crosses the Loop Current, we observe vertically coherent heat flux pulses extending to 800 m depth. These pulses intensify within frontal corridors—high‐shear regions between the Loop Current and detached eddies—acting as hotspots for mid‐depth vertical heat redistribution. Our results demonstrate that these high‐frequency dynamics facilitate significantly deeper vertical connectivity than recognized in current regional budgets. Identifying these deep‐reaching hotspots underscores the necessity of resolving small‐scale processes to improve ocean climate models and hurricane intensity forecasts.

中文摘要

摘要 上层海洋内部的垂直热交换对区域气候具有关键影响，但直接观测难度较大。在墨西哥湾，环流及其相关涡旋显著增强了这种交换过程。高分辨率水下滑翔机观测显示，该输运过程以亚日变率为主导，其强度比背景条件高出一个数量级。当滑翔机轨迹穿越环流时，我们观测到延伸至800米深度的垂直相干热通量脉冲。这些脉冲在锋面走廊——即环流与脱离涡旋之间的高剪切区域——内增强，成为中层垂直热量再分配的热点区域。我们的结果表明，这些高频动力学过程促进了比当前区域预算所认知的更深的垂直连通性。识别这些深达热点的存在，强调了解析小尺度过程对于改进海洋气候模型和飓风强度预报的必要性。

15. GRL — Estimating the Geostrophic–Ageostrophic Transition Scale in Ocean Currents From Wind Generated Waves

  • 作者：Nelson Violante‐Carvalho, Thiago de Paula, Felipe Marques dos Santos, Luiz Mariano Carvalho, Andre Cordeiro dos Santos, Leandro Calado
  • 发表日期：2026-08-13
  • DOI：https://doi.org/10.1029/2025gl120354

Abstract

Abstract SWOT resolves sea surface height at spatial scales where geostrophic balance may break down and ageostrophic motions become significant, making identification of the transition scale essential. We test whether wind generated waves provide an independent diagnostic of this transition. WAVEWATCH III was forced with high resolution surface currents decomposed into geostrophic and ageostrophic components for two contrasting regimes: an energetic Brazil Current region and a calmer South Atlantic interior. Wavenumber spectra of significant wave height yield crossover scales consistent with those inferred from current KE spectra. We also examine the wave action flux after decomposition into rotational and divergent transport components. In the Brazil Current, the flux crossover aligns with the KE transition scale, whereas coherent swell weakens the correspondence in the interior South Atlantic.

中文摘要

摘要 SWOT在准地转平衡可能失效且非地转运动变得显著的空间尺度上解析海面高度，因此识别这一过渡尺度至关重要。我们检验了风生波浪是否能为此过渡提供独立的诊断依据。利用高分辨率表层流场（分解为地转和非地转分量）驱动WAVEWATCH III模式，针对两种对比鲜明的区域：能量充沛的巴西海流区和较为平静的南大西洋内部区。有效波高的波数谱得出的交叉尺度与从流场动能谱推断的尺度一致。我们还考察了波作用通量在分解为旋转和辐散输运分量后的表现。在巴西海流区，通量交叉尺度与动能过渡尺度吻合，而南大西洋内部区相干涌浪的存在削弱了这种对应关系。

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 — Does Oceanic Variability Explain the Intensity of Megadroughts and Megapluvials in the CESM2 Climate Model?（DOI: https://doi.org/10.1175/jcli-d-26-0237.1）
    • 命中: ENSO
    • 排除: paleoclimate