Ocean Modelling最新文献_第4页

Multi-model physics informed neural networks to the shallow water equations for cosine bell advection 多模型物理将神经网络引入余弦钟状平流的浅水方程

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-11-22 DOI: 10.1016/j.ocemod.2025.102656

Susmita Saha , Satyasaran Changdar , Soumen De

Solving the shallow water equations is essential in science and engineering for understanding and predicting geophysical phenomena such as atmospheric and oceanic flows. Physics-informed machine learning has emerged as a powerful alternative to traditional numerical methods, avoiding the complexities of grid generation and enabling mesh-free solutions to partial differential equations. In this study, we apply a sequential multi-model approach within a time-decomposed framework to solve the shallow water equations on a rotating sphere, in the context of meteorological applications. We employed advanced physics-informed neural networks integrated with deep learning, using diverse network architectures to conduct a detailed analysis of cosine bell advection across multiple orientations on the Earth. The results demonstrate high predictive accuracy, underscoring the method’s transformative potential for geophysical fluid dynamics. We also implemented a finite difference upwind scheme and a fully data-driven deep neural network to supplement the validation process and comparative analysis. Additionally, we perform a sensitivity analysis to examine the influence of physics-informed error terms on the training dynamics of the networks.

在科学和工程中，求解浅水方程对于理解和预测大气和海洋流动等地球物理现象至关重要。物理知识的机器学习已经成为传统数值方法的强大替代方案，避免了网格生成的复杂性，并使偏微分方程的无网格解成为可能。在这项研究中，我们在时间分解框架内应用序列多模型方法来求解气象应用背景下旋转球体上的浅水方程。我们采用了先进的物理信息神经网络与深度学习相结合，使用不同的网络架构对地球上多个方向的余弦钟平流进行了详细分析。结果显示了较高的预测精度，强调了该方法在地球物理流体动力学方面的变革潜力。我们还实现了一个有限差分迎风方案和一个完全数据驱动的深度神经网络，以补充验证过程和比较分析。此外，我们进行了敏感性分析，以检查物理通知误差项对网络训练动态的影响。

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引用次数: 0

Implementation and evaluation of a new parameterization of submesoscale vertical flux in a mesoscale-resolving model in the North Pacific 北太平洋中尺度解析模式中亚中尺度垂直通量新参数化的实现与评价

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-11-20 DOI: 10.1016/j.ocemod.2025.102655

Zhe Feng , Zhiwei Zhang , Jinchao Zhang , Wenda Zhang , Man Yuan , Zhao Jing , Wei Zhao , Jiwei Tian

Submesoscale processes play a key role in re-stratifying the upper ocean through inducing strong vertical buoyancy flux (VBF). Because the prevailing climate and global ocean models are unable to resolve submesoscale processes, submesoscale VBF needs to be parameterized in models to reduce the associated simulation bias. Recently, Zhang et al. (2023) proposed a new VBF parameterization which simultaneously considers submesoscale baroclinic instability and strain-induced frontogenesis (Zhang23 parameterization hereafter). In this study, we implement the Zhang23 parameterization in a mesoscale-resolving (9-km) configuration of Regional Ocean Modeling System (ROMS) for the North Pacific, and assess its impact by comparing results with observations and a submesoscale-resolving (1-km) simulation. The parameterized VBFs have similar magnitudes and spatial patterns with those derived from the 1-km simulation, demonstrating the effectiveness of Zhang23 parameterization. Additionally, the Zhang23 parameterization yields significantly reduced mixed-layer depth (MLD) and strengthened upper-ocean stratification in winter compared with those in the control run without this parameterization. In the Kuroshio Extension region, the sensitivity run including the Zhang23 parameterization reduces the deep MLD bias by 94 % and yields an upper-ocean stratification in better agreement with a submesoscale-resolving simulation. These results show that the Zhang23 parameterization has a good potential to improve the simulation of upper-ocean processes in mesoscale-resolving models.

亚中尺度过程通过诱导强垂直浮力通量（VBF）在上层海洋重新分层中起关键作用。由于主流气候和全球海洋模式无法解析亚中尺度过程，因此需要在模式中参数化亚中尺度VBF以减少相关的模拟偏差。最近，Zhang等（2023）提出了一种同时考虑亚中尺度斜压不稳定和应变诱导锋生的VBF参数化方法（Zhang23参数化后见下文）。在本研究中，我们在北太平洋区域海洋模拟系统（ROMS）的9 km中尺度分辨率配置中实现了Zhang23参数化，并通过与观测结果和亚中尺度分辨率（1 km）模拟的比较来评估其影响。参数化的vfs与1 km模拟的vfs具有相似的大小和空间格局，证明了Zhang23参数化的有效性。此外，与未进行参数化的对照组相比，Zhang23参数化显著降低了冬季混合层深度（MLD），强化了上层海洋分层。在黑潮扩展区，包括Zhang23参数化在内的敏感性运行将深层MLD偏差降低了94%，并产生了与亚中尺度分辨模拟更一致的上层海洋分层。这些结果表明，Zhang23参数化在中尺度解析模式中具有改善上层海洋过程模拟的良好潜力。

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引用次数: 0

Significant wave height prediction using a novel hybrid model of group method of data handling 用一种新的混合模型分组数据处理方法进行显著波高预测

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-11-15 DOI: 10.1016/j.ocemod.2025.102654

Naiwen Mei , Zhonglian Jiang , Bingchang Weng , Zhen Yu , Shijun Chen

Significant wave height (WVHT) has been identified as a key influencing factor in the research fields of coastal engineering, naval architecture and ocean engineering, maritime management, and other related disciplines. The wave height sequences are always featured as nonlinear and non-stationary, thus seriously concerned in ship voyage planning and route selection. The refined WVHT prediction will support the ship speed optimization and energy efficiency management. A novel hybrid model based on Variational Mode Decomposition (VMD) and Group Method of Data Handling (GMDH) has been proposed. Intrinsic mode functions (IMFs) of WVHT sequence were obtained by VMD, which were subsequently adopted as model inputs of GMDH. The contribution of various input variables was explored through sensitivity analysis. The hybrid VMD-GMDH model was validated through field dataset of National Data Buoy Center, and evaluated with different metrics. Its performance was further compared with four other models, namely GMDH, EMD-GMDH, GRU and VMD-LSTM. The results highlight the importance of data preprocessing through VMD and the prediction accuracy is greatly improved. Specifically, the Mean Squared Error (MSE), Root Mean Squared Error (RMSE), Mean Absolute Percentage Error (MAPE) and Mean Absolute Error (MAE) decrease by 29.1%, 15.8%, 18.6% and 15.8%, respectively. The correlation coefficient (R²) is improved by 3.32%. The novel hybrid VMD-GMDH model provides an effective tool for WVHT prediction and would support the intelligent oceanographic studies.

有效波高（Significant wave height， WVHT）在海岸工程、船舶与海洋工程、海事管理等相关学科的研究中已被确定为一个关键的影响因素。波浪高度序列具有非线性和非平稳性，在船舶航次规划和航路选择中具有重要意义。精细化的WVHT预测将支持航速优化和能效管理。提出了一种基于变分模态分解（VMD）和数据处理成组方法（GMDH）的混合模型。通过VMD获得WVHT序列的内禀模态函数（IMFs），并将其作为GMDH的模型输入。通过敏感性分析探讨了各输入变量的贡献。通过国家数据浮标中心的野外数据集对VMD-GMDH混合模型进行了验证，并用不同的指标进行了评价。进一步与GMDH、EMD-GMDH、GRU、VMD-LSTM四种模型进行性能比较。结果表明，通过VMD对数据进行预处理的重要性，预测精度得到了很大的提高。其中，均方误差（MSE）、均方根误差（RMSE）、平均绝对百分比误差（MAPE）和平均绝对误差（MAE）分别下降了29.1%、15.8%、18.6%和15.8%。相关系数（R2）提高3.32%。该混合模式为WVHT预报提供了有效的工具，为智能海洋研究提供了支持。

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引用次数: 0

Assessing the effects of sea level rise on ocean waves and surge events along the victorian coast 评估海平面上升对维多利亚海岸的海浪和浪涌事件的影响

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-11-14 DOI: 10.1016/j.ocemod.2025.102653

Rui Li , Huy Quang Tran , Jak McCarroll , Alexander V. Babanin

This study investigates nonlinear surges and extreme wind-wave patterns off the coast of Victoria by simulating sea level rise (SLR) scenarios of 0.5, 0.8, 1.0 and 1.4 meters alongside a 31-year hindcast (1990–2020) using the validated SCHISM-WWMIII coupled wave-circulation model. Model simulations were compared with observational data, confirming the accuracy of the results. Our findings indicate that sea levels along the Victorian coast have been rising at a rate of 1.46 × 10^⁻² cm/year, while wave heights in the Southern Ocean have also increased over time. However, the rate of wave height increase is lower along the Victorian coast compared to the Southern Ocean. Due to island blocking, mean wave heights in Bass Strait remain lower than those in the Southern Ocean, yet extreme water levels in the strait exceed those in the open ocean. The impact of SLR is most pronounced in the waters south of Tasmania, where maximum elevations exceed 1.2 meters under the 1.0-meter SLR scenario. SLR contributes to higher mean water levels and increased wave heights off the coast of Victoria, underscoring the complex interactions between rising sea levels and coastal wave dynamics. Wave direction and peak period were also examined, but their changes under SLR scenarios were found to be minimal. These findings highlight the importance of incorporating both SLR and wave dynamics into coastal hazard assessments to better understand future risks.

本研究利用经验证的schistic - wwmiii波浪环流耦合模式，模拟了1990-2020年31年的海平面上升（SLR）情景（0.5、0.8、1.0和1.4米），研究了维多利亚海岸的非线性涌浪和极端风浪模式。将模型模拟结果与观测数据进行了比较，证实了结果的准确性。我们的研究结果表明，维多利亚海岸的海平面一直在以每年1.46 × 10⁻2厘米的速度上升，而南大洋的海浪高度也随着时间的推移而增加。然而，与南大洋相比，维多利亚海岸的浪高增长率较低。由于岛屿阻塞，巴斯海峡的平均波高仍然低于南大洋，但海峡的极端水位超过了公海。单反的影响在塔斯马尼亚岛以南的水域最为明显，在1.0米单反的情况下，那里的最大海拔超过1.2米。SLR导致了维多利亚海岸平均水位的上升和浪高的增加，强调了海平面上升和海岸波浪动力学之间复杂的相互作用。波浪方向和峰值周期也进行了研究，但发现它们在单反情景下的变化很小。这些发现强调了将SLR和波浪动力学结合到海岸危害评估中的重要性，以更好地了解未来的风险。

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引用次数: 0

Equations for modelling contaminant impacts throughout a marine ecosystem 模拟整个海洋生态系统中污染物影响的方程

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-11-07 DOI: 10.1016/j.ocemod.2025.102646

Raisha Lovindeer , Elizabeth A. Fulton , Susan E. Allen , Javier Porobic , Douglas J. Latornell , Hem Nalini Morzaria-Luna , Alaia Morell

Biological risk assessment modelling for oil spills using whole-of-ecosystem models has the benefit of assessing species-specific toxicology and the chronic impact of oil spills by layering these impacts on top of the already-built ecosystem within the model. In deterministic models this approach requires tracking contaminants as they move throughout the biology of the ecosystem, from uptake to loss. Here we consolidate, modify, and add to existing equations to produce a synergistic set that can be used to define the impact of contaminants on biological groups throughout the food web. We demonstrate how these equations work, individually as well as in tandem, for oil-based contaminants by implementing them in a three-dimensional marine ecosystem model. We assess the sensitivity of parameters within these equations, showing the impact on the model outcome. Although we focus on oil-based contaminants in our examples, the equations presented can be applied to any contaminants in the aquatic or marine environment.

利用整个生态系统模型对石油泄漏进行生物风险评估建模，通过将这些影响叠加在模型中已经建立的生态系统之上，可以评估特定物种的毒理学和石油泄漏的慢性影响。在确定性模型中，这种方法需要跟踪污染物在生态系统中从吸收到流失的整个生物过程。在这里，我们整合、修改并添加到现有的方程中，以产生一个协同集，可用于定义污染物对整个食物网生物群体的影响。通过在三维海洋生态系统模型中实现这些方程，我们演示了这些方程如何单独或串联地对油基污染物起作用。我们评估了这些方程中参数的敏感性，显示了对模型结果的影响。虽然我们在例子中关注的是油基污染物，但所提出的方程可以应用于水生或海洋环境中的任何污染物。

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引用次数: 0

Tsunami data assimilation and forecast in the Kii Channel using high-frequency radar: Bathymetry effects on the propagation of measurement errors 利用高频雷达同化和预报Kii海峡的海啸资料：测深对测量误差传播的影响

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-11-05 DOI: 10.1016/j.ocemod.2025.102651

Muhammad Irham Sahana , Ryotaro Fuji , Hirofumi Hinata

High-frequency (HF) radar has become a promising tool for tsunami forecasting based on assimilation of surface current data. However, the accuracy of HF radar-derived velocity vectors is affected by multiple error sources, including sea surface conditions, ionospheric disturbances, human activities, and inherent measurement errors associated with the beam-crossing angles. If not properly accounted for, these errors can degrade the tsunami forecast accuracy. This study explored the influence of realistic bathymetry on the propagation and amplification of noise-induced (measurement error-induced) tsunamis. These tsunamis caused localized variations in the assimilated and forecasted tsunami heights, particularly through refraction and shoaling. Measurement error assimilation with energy ray tracing has significant implications for tsunami early warning systems: it helps identify regions likely to undergo noise-induced tsunamis originating from radar coverage. By incorporating beam-angle-dependent measurement errors into the optimal interpolation method and considering actual bathymetry, we achieved stable and accurate tsunami forecasts for the Mw 9.0 Nankai Trough earthquake scenario. The method predicted maximum coastal tsunami heights 23–78 min before they arrived at Osaka Bay, with 92 % forecast accuracy and 0.8 % standard deviation across 15 experiments. In addition, careful tuning of the optimal characteristic length (L) in relation to tsunami velocities and observation errors was found to be crucial for balancing the suppression of noise-induced tsunamis and retention of tsunami signals. Both excessively small and large values of L degraded the performance, underscoring the importance of dynamic tuning for operational systems. Future research should focus on optimizing the assimilation parameters by monitoring the measurement error status.

高频（HF）雷达已成为一种很有前途的基于表面流资料同化的海啸预报工具。然而，高频雷达速度矢量的精度受到多种误差源的影响，包括海面条件、电离层干扰、人类活动以及与波束穿越角相关的固有测量误差。如果不加以适当的考虑，这些误差会降低海啸预报的准确性。本研究探讨了现实测深对噪声（测量误差）海啸传播和放大的影响。这些海啸引起了同化和预测海啸高度的局部变化，特别是通过折射和浅滩作用。利用能量射线追踪的测量误差同化对海啸预警系统具有重要意义：它有助于确定雷达覆盖范围内可能发生由噪声引起的海啸的区域。通过将波束角相关测量误差纳入最优插值方法，并结合实际测深，实现了Mw 9.0南开海槽地震情景下稳定、准确的海啸预报。该方法在海啸到达大阪湾前23-78分钟预测了最大海岸海啸高度，15次实验的预测精度为92%，标准偏差为0.8%。此外，仔细调整与海啸速度和观测误差相关的最佳特征长度(L)对于平衡噪声引起的海啸的抑制和海啸信号的保留至关重要。L的值过小或过大都会降低性能，这强调了动态调优对操作系统的重要性。未来的研究应着眼于通过监测测量误差状态来优化同化参数。

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引用次数: 0

Three-dimensional spatiotemporal simulation of tritium discharge from Fukushima 福岛氚排放的三维时空模拟

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-11-03 DOI: 10.1016/j.ocemod.2025.102652

Yi Liu , Zhen-Zhong Hu , Robert H. Richmond , Jian-Min Zhang , Chang Zhao , Shengli Chen

The ALPS treated water has been discharged into the Pacific Ocean since August 2023. This study investigates this discharge using a newly developed three-dimensional dispersion model that incorporates migration, diffusion, and decay processes of radionuclides. A simulation over ten years is conducted using reanalyzed oceanographic data. The results indicate that tritium released from Fukushima primarily disperses eastward along the 35°N latitude line. In later stages, local concentration peaks emerge in the northeastern Pacific, exceeding those in the northwest Pacific. For the vertical distribution, the tritium is generally reduced greatly with depth, but displays maximum values at subsurface layer (∼50m) in some regions. The concentration reaches a steady state over time, defined as the characteristic concentration, whose spatial distribution and attainment time are detailed. For major fishing grounds in the Pacific Ocean, the Hokkaido area shows the highest tritium levels, followed by Hawaii, California, Zhoushan, the Korean Peninsula, Mexico, the Philippines, Alaska, and Peru in descending order. Critically, simulated tritium concentrations in most North Pacific regions (∼0.01 Bq/m³) remain orders of magnitude below natural background levels (∼50 Bq/m³). This research elucidates three-dimensional radionuclide dispersion mechanisms in global oceans, providing a quantitative methodology for future marine emergency response and contributing to long-term marine conservation efforts.

自2023年8月以来，阿尔卑斯山处理过的水被排放到太平洋。本研究使用一个新开发的三维色散模型来研究这种放电，该模型包含了放射性核素的迁移、扩散和衰变过程。利用重新分析的海洋学资料进行了为期十年的模拟。结果表明，福岛核泄漏的氚主要沿北纬35°向东扩散。在后期，局部浓度高峰出现在东北太平洋，超过西北太平洋。在垂直分布上，氚一般随深度的增加而大幅度减少，但在某些区域在近地表（~ 50m）处达到最大值。浓度随时间达到稳定状态，定义为特征浓度，详细描述了其空间分布和达到时间。在太平洋的主要渔场中，氚含量最高的是北海道地区，依次为夏威夷、加利福尼亚、舟山、朝鲜半岛、墨西哥、菲律宾、阿拉斯加、秘鲁。重要的是，大多数北太平洋地区的模拟氚浓度（~ 0.01 Bq/m3）仍然比自然背景水平（~ 50 Bq/m3）低几个数量级。这项研究阐明了全球海洋中的三维放射性核素扩散机制，为未来的海洋应急反应提供了定量方法，并有助于长期的海洋保护工作。

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引用次数: 0

Investigating the impact of meteorological factors on sea-level variability in the northwestern Arabian gulf: A case study using deep learning and advanced statistical models for enhanced forecasting 调查气象因素对阿拉伯湾西北部海平面变化的影响：使用深度学习和高级统计模型增强预报的案例研究

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-11-02 DOI: 10.1016/j.ocemod.2025.102648

Abather J.B. Alhallaf , Javier Vilcáez , Ye Liang

This study evaluates how incorporating meteorological variables affects the predictive accuracy of sea-level variability (SLV) models in the northwestern Arabian Gulf, utilizing SARIMAX, LSTM, and CNN&LSTM models. The analysis indicates that the total monthly meteorological contributions, as a proportion of overall tidal influences on SLV, reach their peak in summer, with July and August exhibiting the highest total monthly weights, aligning with previous studies. Air Temperature (AT) is the principal parameter influencing SLV, accounting for a maximum of 28.35% in August, highlighting climate change's persistence on sea level. The models consistently identify Atmospheric Pressure (AP) as a consistent contributor with a minor negative effect; Wind Speed (WS), Wind Direction (WD), and Gust Speed (GS) exhibit mixed effects depending on the month. The LSTM and CNN&LSTM models also indicate that some factors inversely affect sea-level changes. This study highlights the significance of integrating metrological factors into sea-level forecasting models in the northwestern Arabian Gulf to enhance flood prediction. It has potential applications in disaster preparedness and the execution of coastal flooding mitigation strategies.

本研究利用SARIMAX、LSTM和CNN&；LSTM模型，评估了纳入气象变量如何影响阿拉伯湾西北部海平面变率（SLV）模型的预测精度。分析表明，月气象总贡献占总潮汐影响SLV的比例在夏季达到峰值，其中7月和8月的月总权重最高，与前人的研究结果一致。气温（AT）是影响SLV的主要参数，在8月份最大占28.35%，突出了气候变化对海平面的持续性。这些模式一致地将大气压力（AP）确定为具有轻微负面影响的一致贡献者；风速（WS）、风向（WD）和阵风速度（GS）在不同月份表现出混合效应。LSTM和CNN&；LSTM模式也表明一些因子对海平面变化有负相关影响。本研究强调了将气象因子整合到阿拉伯湾西北部海平面预报模型中对加强洪水预报的意义。它在备灾和执行沿海洪灾减灾战略方面具有潜在的应用前景。

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引用次数: 0

Local effect of a submesoscale parameterization scheme and its remote influences on large-scale circulation in the Northwest Pacific 一个亚中尺度参数化方案的局地效应及其对西北太平洋大尺度环流的远程影响

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-10-31 DOI: 10.1016/j.ocemod.2025.102650

Ziyi Zhang , Bo An , Zhiwei Zhang , Yuyang Guo , Jinchao Zhang , Zhe Feng , Yongqiang Yu

Submesoscale processes play important roles in vertical heat and mass transport, modulating mesoscale eddies and the energy cycle; thus a parameterization is essential for most ocean models due to submesoscale’s spatial scales (∼100 m–10 km). This study describes the impact of the submesoscale parameterization scheme by Zhang et al. (2023; Zhang23) in a regional eddy-resolving ocean model in the North Pacific. Compared with the numerical experiment without the scheme, the simulated winter mixed-layer depth (MLD) bias is reduced by 70 % in the Kuroshio Extension (KE) region and the KE jet shifted southward from 36.5°N to 35.5°N, closer to observations. Surface cold biases at 32°–34°N and subsurface warm biases at 36–40°N are reduced by ∼1 °C and ∼2 °C across four seasons, respectively. The effect of submesoscale vertical buoyancy fluxes (VBF) on winter MLD is debated. While widely shown to promote basin-scale shoaling via restratification, they are also known to cause powerful, localized deepening in regions with strong fronts and air-sea interaction. Focusing on this latter scenario, our study reveals a more detailed mechanism, notably distinguishing between local (direct) and remote (indirect) impacts on circulation in the mixed layer and subsurface. Enhanced submesoscale VBF drives weather-scale MLD deepening and subduction along tilted isopycnals in boreal winter in the most active eddy region, mainly limited to 38°–42°N/140°–150°E, promoting southward subsurface cooling and strengthening ocean memory. This feedback modulates the KE's large-scale circulation by shifting its path southward, reducing downstream heat transport, and promoting stratification and shoaling in the eastern region throughout all seasons. These findings demonstrate the importance of submesoscale parameterization for improving simulations of western boundary current systems and highlight its effects in representing remote and subsurface dynamic processes.

亚中尺度过程在垂直热质输运、调节中尺度涡旋和能量循环中起重要作用；因此，由于亚中尺度的空间尺度（~ 100 m-10 km），对大多数海洋模式来说，参数化是必不可少的。本文描述了Zhang et al. （2023; Zhang23）的亚中尺度参数化方案对北太平洋区域涡旋解析海洋模式的影响。与不采用该方案的数值试验相比，模拟黑潮延伸（KE）地区冬季混合层深度（MLD）偏差减小了70%，KE急流从36.5°N向南移动至35.5°N，与观测值更接近。在32°-34°N的地表冷偏差和36-40°N的地下暖偏差在四个季节中分别减少了~ 1°C和~ 2°C。讨论了亚中尺度垂直浮力通量（VBF）对冬季MLD的影响。虽然它们被广泛证明可以通过再酸化促进盆地尺度的浅滩化，但在锋面强和海气相互作用的地区，它们也会导致强大的局部深化。针对后一种情况，我们的研究揭示了更详细的机制，特别是区分了对混合层和地下环流的局部（直接）和远程（间接）影响。亚中尺度VBF的增强，在最活跃的涡动区（主要局限于38°-42°N/140°-150°E），驱动了北纬冬季天气尺度MLD沿倾斜等平线加深和俯冲，促进了向南的地下冷却，增强了海洋记忆。这种反馈调节了KE的大尺度环流，使其路径南移，减少了下游的热输送，并在整个季节促进了东部地区的分层和浅滩化。这些发现表明了亚中尺度参数化对于改善西部边界流系统模拟的重要性，并突出了其在表征远程和地下动力过程方面的作用。

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引用次数: 0

Surface current detection in regional seas using Lagrangian coherent structures 基于拉格朗日相干结构的区域海洋表面流探测

IF 2.9 3区地球科学 Q2 METEOROLOGY & ATMOSPHERIC SCIENCES

Ocean Modelling

Pub Date : 2025-10-31 DOI: 10.1016/j.ocemod.2025.102647

Huy Cong Vu, Binh Quang Nguyen

Eddies play a vital role in the transport of heat, salt, and other materials, as well as in shaping the circulation structure of the ocean. Understanding eddies is therefore essential for elucidating the mechanisms that govern the formation, evolution, and variability of ocean currents. This study aims to analyze the characteristics of ocean currents in the East Vietnam Sea (South China Sea–SCS) by combining two approaches: the Euler method and the Lagrangian Coherent Structures (LCS) method. This integrated approach provides a comprehensive understanding of current dynamics and eddy formation. Using velocity vector images (Euler method), the study identifies the direction, location, and intensity of major ocean currents in the SCS. Meanwhile, the LCS method is applied to detect and delineate the boundaries and sizes of eddies. The ocean current data were obtained from the global HYCOM model on a daily basis throughout 2023. Our findings indicate that: (i) ocean currents in the SCS exhibit a clear seasonal pattern. In winter, the dominant flow moves from north to south along the Vietnamese coast, while in summer, the flow reverses, moving from south to north, with a disruption near 11 °N close to the Vietnamese coast. The current can extend up to 220 km near China, narrowing to 56 km as it approaches Vietnam. (ii) A table summarizing the characteristics of eddies with diameters greater than 100 km is included. The number of eddies is higher during the summer, but larger eddies tend to occur during the winter. In addition to single eddies, the SCS is also home to double and triple eddies.

漩涡在热、盐和其他物质的运输中起着至关重要的作用，也在塑造海洋的环流结构中起着至关重要的作用。因此，了解涡流对于阐明控制洋流形成、演化和变化的机制至关重要。本研究旨在结合欧拉方法和拉格朗日相干结构（LCS）方法分析东越南海（南中国海）洋流特征。这种综合方法提供了对电流动力学和涡流形成的全面理解。利用速度矢量图像（欧拉法），该研究确定了南海主要洋流的方向、位置和强度。同时，利用LCS方法对涡流的边界和大小进行检测和圈定。2023年的海流数据来自全球HYCOM模型的每日数据。我们的研究结果表明：(1)南海洋流表现出明显的季节性模式。冬季主要气流沿越南海岸由北向南移动，夏季主要气流由南向北移动，在靠近越南海岸的11°N附近出现中断。洋流在中国附近可以延伸220公里，在接近越南时缩小到56公里。（ii）附有一个表，概述了直径大于100公里的涡流的特征。涡旋的数量在夏季较高，但较大的涡旋往往发生在冬季。除了单涡旋外，南海还有双涡旋和三涡旋。

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