Tide‐topography interactions, key drivers of upwelling and mixing, remain poorly understood within the Cape Verde area (CVA) and the Senegalo‐Mauritanian upwelling regions. Therefore, a three‐dimensional numerical model, initialized with horizontally uniform stratification and driven by barotropic tidal forcing only, is employed to study the life cycle of the internal tide (IT) in the region. The CVA is identified as a major IT source in the tropical northeast Atlantic. In the model, approximately 1870 MW of M2 IT energy is generated from barotropic tides, with nearly 48% dissipating locally. The São Nicolau strait, as part of the West Barlavento island system, serves as a critical energy source with outward propagating nonlinear ITs. Superposition of multisource ITs shapes the internal wave field in the internal sea of the Cape Verde archipelago, characterized by a standing wave pattern with an anticlockwise rotational tidal wave system. Along the continental margin, ITs are locally generated and modified by the remotely generated ITs from the CVA, with a predominantly inshore energy flux north of Dakar and an offshore flux to the south. The region north of Dakar is characterized as an energy sink area where approximately 86% (84.5 MW) of IT energy is dissipated, whereas the region south of Dakar is identified as a generation spot where approximately 22% (16.6 MW) of IT energy radiates offshore into the open sea.

Ocean internal waves occur in stably stratified seawater and play a crucial role in energy cascade, material transport, and military activities. However, the complex and irregular spatial patterns of internal waves pose significant challenges for accurate detection in SAR images when using conventional convolutional neural networks, which often lack adaptability to geometric variations. To address this problem, this paper proposes a refined Faster R-CNN detection framework, termed “rFaster R-CNN”, and adopts a transfer learning strategy to enhance model generalization and robustness. In the feature extraction stage, a backbone network called “ResNet50_CDCN” that integrates the CBAM attention mechanism and DCNv2 deformable convolution is constructed to enhance the feature expression ability of key regions in the images. Experimental results show that in the internal wave dataset constructed in this paper, this network improves the detection accuracy by approximately 3% compared to the original ResNet50 network. At the region proposal stage, this paper further adds two small-scale anchors and combines the ROI Align and FPN modules, effectively enhancing the spatial hierarchical information and semantic expression ability of ocean internal waves. compared with classical object detection algorithms such as SSD, YOLO, and RetinaNet, the proposed “rFaster R-CNN” achieves superior detection performance, showing significant improvements in both accuracy and robustness.

The mesoscale eddy dipole (MED) in the western South China Sea is characterized by a seasonal pair of cold and warm eddies, which typically appear off the Vietnam coast from July to September, accompanied by an eastward jet (EJ) traversing the MED between 11°N and 12°N. However, detailed investigations into the interactions between the MED and EJ remain limited in previous studies. In this study, the interactions between the MED and EJ in 2011 are examined from both morphologic and energetic perspectives using the Oceanic Regional Circulation and Tidal Model. Variations in their intensity and position are strongly correlated. Multiscale energy transfer analysis reveals a notable positive energy cascade from the EJ to the MED. Mixed barotropic and baroclinic instabilities, primarily occurring in the upstream region of the EJ, promote the formation and development of the MED. In contrast, in the mid‐downstream region, part of kinetic energy is inversely transferred from mesoscale eddies to the large‐scale circulation, facilitating the stretching and intensification of the EJ. The distribution of eddy–mean flow energy transfer is distinctly anisotropic, with stronger energetic interactions in the upstream part of the EJ horizontally and within the cold eddy of the MED meridionally. This study advances our understanding and underscores the need for greater attention to this highly seasonal eddy–mean flow dynamic system.

Tide-topography interactions are key drivers of tidal dynamics in the Cape Verde and Senegalo-Mauritania Upwelling regions. Internal tide (IT)-induced turbulent mixing plays a vital role in supporting marine ecosystems. Three-dimensional IT simulations identify the Cape Verde area (CVA) as the primary IT source in the tropical Northeast Atlantic, generating approximately 1.87 GW of M2 IT energy from barotropic tides, with nearly 48% dissipating locally. The West Barlavento Islands serve as a critical energy source, characterized by outward-propagating nonlinear internal waves from the São Nicolau Strait. The distribution and geometry of the islands largely shape a partially standing wave pattern within the Cape Verde Sea. Along the continental margins, distinct topographic features produce contrasting IT dynamics north and south of Dakar. Approximately 9 % (85.8 MW) of the CVA IT energy propagates eastward into the Cape Verde Plateau (CVP) region, with 22.3 MW radiating into the North Dakar area (NDA). Canyon-seamount systems along the NDA slope contribute 75.4 MW, significantly enhancing the onshore energy flux and dissipation over the NDA shelf. In the South Dakar area (SDA), approximately 25% (16.6 MW) of the energy generated over the continental slope radiates offshore into the CVP deep basin, where it interferes with the eastward propagating IT from the CVA. The differences in wave energy distributions are primarily shaped by topography with marginal modulation by seasonal stratification across the CVA and Eastern Boundary Upwelling region.

Tide-topography interactions are key drivers of tidal dynamics in the Cape Verde and Senegalo-Mauritania Upwelling regions. Three-dimensional internal tide (IT) simulations identify the Cape Verde Area (CVA) as the primary IT source in the Eastern Boundary Upwelling region off Northwestern Africa, generating approximately 1.87 GW of M2 IT from barotropic tides, with nearly 48% dissipating locally. The West Barlavento Islands serve as a critical energy source, characterized by outward-propagating nonlinear internal waves from the São Nicolau Strait. The distribution and geometry of Islands largely shape a partially standing wave within the Cape Verde Sea. Along the continental margins, distinct topographic features produce contrasting IT dynamics north and south of Dakar. Approximately 9 % (85.8 MW) of the remaining CVA energy propagates eastward into the Cape Verde Plateau (CVP), with 22.3 MW radiating into the North Dakar Area (NDA). Canyon-Seamount systems along the NDA slope contribute 75.4 MW, significantly enhancing onshore energy flux and dissipation over the NDA shelf. In the South Dakar Area (SDA), energy generated over the steeper continental slope radiates offshore by approximately 25% (16.6 MW) into the CVP deep basin, where it interacts with westward propagating IT from the CVA. Onshore shoaling IT with high potential energy flourishes on the SDA shelf. Seasonal stratification significantly influences the IT dynamics with elevated wave energy over the continental slope during winter. Wave-induced turbulent mixing plays a vital role in supporting ecosystems across the Cape Verde and Senegalo-Mauritania Upwelling regions.

The Luzon Strait is a critical generation site for global internal tides. Their generation and propagation are significantly modulated by background currents, including the Kuroshio Current and mesoscale eddies. This study investigates nonlinear effects of these background currents on low-mode (modes 1–3) internal tides using a high-resolution numerical simulation. We apply the Taylor–Goldstein equation considering the Earth’s rotation and background currents to perform modal decomposition, and utilize a nonlinear internal tidal energy equation to quantify three crucial energy pathways: inter-modal energy conversion, nonlinear energy exchange with background currents, and nonlinear advection effects. Results demonstrate that while stationary mode-1 internal tides dominate in the generation region of the Luzon Strait, non-stationary energy increases significantly in the western and eastern propagation regions, driven largely by seasonal variability of the Kuroshio Current. Inter-modal energy conversion follows a cascade from lower to higher modes, with conversion efficiency increasing with mode number. Nonlinear exchanges between background currents and internal tides are one order of magnitude smaller than inter-modal conversions but exhibit a bidirectional transfer, where advection redistributes internal tidal energy within the eddy structures. This study provides a quantitative framework for understanding multiscale energy pathways of internal tides under complex ocean dynamics.