Coastal EngineeringPub Date : 2025-04-25DOI: 10.1016/j.coastaleng.2025.104766
Sunke Trace-Kleeberg , Krijn Saman , Robert Vos , Elja Huibregtse , Ivan D. Haigh , Marc Walraven , Annette Zijderveld , Susan Gourvenec
{"title":"Assessing the role of a probabilistic model for guiding storm surge barrier maintenance","authors":"Sunke Trace-Kleeberg , Krijn Saman , Robert Vos , Elja Huibregtse , Ivan D. Haigh , Marc Walraven , Annette Zijderveld , Susan Gourvenec","doi":"10.1016/j.coastaleng.2025.104766","DOIUrl":"10.1016/j.coastaleng.2025.104766","url":null,"abstract":"<div><div>Storm surge barriers provide flood protection to many major coastal cities in estuaries around the world. Maintenance of these assets is critical to ensure they remain reliable and continue to comply with national legal protection standards. There are often critical thresholds of environmental conditions, beyond which maintenance work is unsafe to be carried out. However, as storm surge barriers age and with climate change effects such as sea-level rise and possible changes in storminess, periods when environmental conditions exceed set thresholds will occur more frequently, so carrying out the required work in available maintenance windows will become increasingly challenging. Probabilistic models enable the use of ensemble forecasts of upcoming water levels to determine the likelihood of conditions exceeding the threshold and so can inform on decision making regarding maintenance. This paper evaluates a probabilistic model currently in operational use by Rijkswaterstaat, the Dutch Ministry of Infrastructure and Water Management, to guide maintenance decisions at the Maeslant barrier in the Netherlands. Sixteen years of historic highwater level forecasts from a combination of European Centre for Medium-Range Weather Forecasts and Dutch Continental Shelf Model v5 are used with observations from the Hoek van Holland tide gauge to evaluate and sensitivity test the probabilistic model. Binary classification is used to assess the performance of the probabilistic model. Findings show that the model is conservative with 33.1 % of outcomes resulting in a False Alarm. Changing the baseline parameters of critical probability and water level threshold impacts the balance between False Alarm and Miss outcomes. Increasing the critical probability reduces the number of False Alarms but increases the Miss situations, emphasising the trade-off between acceptable risk and time available to carry out maintenance work. This study highlights the delicate balance between model parameter selection and the associated risk with respect to the maintenance of storm surge barriers.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104766"},"PeriodicalIF":4.2,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143924579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-25DOI: 10.1016/j.coastaleng.2025.104767
Yo Fukutani, Makoto Motoki
{"title":"A neural network-based surrogate model for efficient probabilistic tsunami inundation assessment","authors":"Yo Fukutani, Makoto Motoki","doi":"10.1016/j.coastaleng.2025.104767","DOIUrl":"10.1016/j.coastaleng.2025.104767","url":null,"abstract":"<div><div>Probabilistic assessment and uncertainty evaluation of the inundation depth and distribution of tsunamis are critical for developing effective tsunami disaster preparedness and mitigation efforts. However, existing approaches based on nonlinear long wave theory, which is commonly used to analyze tsunami propagation and inundation in shallow waters, are computationally expensive, thereby limiting their practical application to probabilistic assessment, which requires numerous simulations. In this study, we propose an innovative method to reduce the analytical burden of probabilistic tsunami inundation assessment by building a surrogate model using deep neural networks (DNNs). Different inputs are tested, including the slip distribution of an earthquake fault, the initial water level distribution, and the water level distribution over time using linear long wave theory. The results show the possibility of predicting the tsunami inundation depths and inundation distributions with some accuracy directly from the slip distributions of earthquake faults rather than from information on initial water levels and subsequent tsunami water levels. These results indicate that, as long as the information on the slip distribution of a fault is available, the tsunami inundation depth and distribution can be instantly predicted using a surrogate model that has appropriately been trained on the outcomes of physical model simulations. This finding may constitute a breakthrough prediction method. If the probabilistic evaluation of the inundation depth and distribution or the evaluation of uncertainty can be easily performed, then local tsunami risk assessment and various disaster countermeasures based on such an assessment can be promoted.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104767"},"PeriodicalIF":4.2,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143890980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-23DOI: 10.1016/j.coastaleng.2025.104760
Cheng Chen , Yuhong Liu , Yipeng Yao , Xue Wang , Jiayuan Liu
{"title":"Modelling the responses of the salt marsh and its adjacent tidal mudflat to the tidal dyke and different supplied sediments in Laizhou Bay, China","authors":"Cheng Chen , Yuhong Liu , Yipeng Yao , Xue Wang , Jiayuan Liu","doi":"10.1016/j.coastaleng.2025.104760","DOIUrl":"10.1016/j.coastaleng.2025.104760","url":null,"abstract":"<div><div>Intertidal salt marsh degradation due to natural and anthropogenic pressures poses a significant threat to coastal ecosystems. This degradation largely depends on the expansion of salt marsh, and our current understanding and ability to predict how salt marshes respond to varying sediment supplies, especially in relation to tidal dykes, are still limited. This study developed a model by coupling tide movement, plant growth, and sedimentation to simulate the expansion processes of the <em>Suaeda salsa</em> salt marsh and its adjacent tidal mudflat, while also predicting potential future expansion trends. The results revealed that net sediment height was negative in the tidal mudflat but positive in the salt marsh. When suspended matter concentration in tidewater ranged from 10 to 25 g m<sup>−3</sup>, tide mudflat areas would increase and reach a stable maximum, while salt marsh areas would continuously decline. Higher sediment supplies delayed maximum mudflat expansion, suggesting that enhancing sediment availability could mitigate salt marsh loss. However, even with increased sediment, rising sea levels and sediment undersupply over extended periods (decades to centuries) may still result in salt marsh drowning, disappearance, and transformation into tidal mudflats. Our findings highlighted that (i) Pioneer plant survival is crucial for determining salt marsh migration inland or seaward; (ii) Tidal dykes stabilize mudflat areas at the expense of salt marsh loss; (iii) Removing dykes or enhancing sediment supply could help conserve and restore intertidal salt marshes. These insights offer valuable strategies for coastal ecosystem management.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104760"},"PeriodicalIF":4.2,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143879014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-19DOI: 10.1016/j.coastaleng.2025.104764
Gang Tao , Xizeng Zhao , Yadong Hou , Zhaoyuan Huang , Siwen Zhang , Jintao Lu
{"title":"Experimental investigation on scour characteristics and predictive model of monopile foundations under breaking waves","authors":"Gang Tao , Xizeng Zhao , Yadong Hou , Zhaoyuan Huang , Siwen Zhang , Jintao Lu","doi":"10.1016/j.coastaleng.2025.104764","DOIUrl":"10.1016/j.coastaleng.2025.104764","url":null,"abstract":"<div><div>Breaking waves in nearshore regions induce intense sediment transport, leading to significant scour around offshore wind turbine monopile foundations constructed in shallow water areas, thereby threatening structure stability. Due to the complex flow behavior and soil response involved in monopile scour under breaking waves, the scour characteristics and predictive models have not been adequately investigated. This study systematically analyzes the effects of breaking wave parameters, monopile location, and water depth on scour depth and morphology through wave flume experiments. A three-dimensional laser scanning technique was employed to show the evolution of seabed topography. The results indicate that breaking waves cause extensive seabed morphodynamic changes characterized by forming a bar-trough system, which superimpose onto the local scour process around the monopile. Additionally, the pile location parameter <em>α</em>, defined as the ratio of the distance between the monopile and the breaking point to the wavelength, significantly influences the primary scour mechanism, determining the scour depth and morphology. Specifically, when <em>α</em> ranges from 0.35 to 0.55, the monopile is situated in the region of fully developed turbulence, and the maximum scour depth found was approximately 0.5<em>D</em>. As the breaker type transitions from collapsing to plunging, it can prompt the formation of the bar-trough system. Conversely, increasing water depth generates a water cushion effect, suppressing the formation of the bar-trough system and reducing the monopile scour depth. Finally, an empirical formula of monopile scour depth based on <em>KC</em> number, modified Ursell parameter, and monopile location parameter is proposed, which can effectively predict the scour depth in breaking waves.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104764"},"PeriodicalIF":4.2,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143851382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-18DOI: 10.1016/j.coastaleng.2025.104763
Jan Hitzegrad , Lisa Rentsch , Tom K. Hoffmann , Maike Paul , Christian Windt , Torsten Schlurmann , Nils Goseberg
{"title":"Wave-induced hydrodynamics of biogenic structures in the central Wadden Sea: Implications of the transformation from mussel beds to oyster reefs for wave attenuation","authors":"Jan Hitzegrad , Lisa Rentsch , Tom K. Hoffmann , Maike Paul , Christian Windt , Torsten Schlurmann , Nils Goseberg","doi":"10.1016/j.coastaleng.2025.104763","DOIUrl":"10.1016/j.coastaleng.2025.104763","url":null,"abstract":"<div><div>The transformation of the predominant biogenic structures in the Wadden Sea, from blue mussel (<em>Mytilus edulis</em>) beds to Pacific oyster (<em>Magallana gigas</em>) reefs, has increased their topographical roughness, impacting the wave-biogenic structure interactions. Despite the general knowledge of increased wave attenuation due to the ecological transformation, a detailed quantification of wave energy dissipation induced by both biogenic structures and a comprehensive understanding of the governing processes remain lacking. This study systematically investigates frictional wave energy dissipation of both biogenic structures by subjecting generic surrogate models to regular, non-breaking waves in reduced-scale wave flume experiments. The results reveal pronounced wave height reductions for both structures, with <em>oyster</em> reefs exhibiting approximately twice the frictional wave energy dissipation (wave friction factor <em>f</em><sub><em>w,OR</em></sub> <em>=</em> 0.44 ± 0.30) of <em>mussel</em> beds (<em>f</em><sub><em>w,MB</em></sub> = 0.21 ± 0.18). Comparing near-bed velocities with topographical roughness parameters identified mussel agglomerations governing the frictional wave energy dissipation in mussel beds and oyster shells in oyster reefs. In <em>mussel</em> beds, form drag dominates frictional resistance under moderate hydrodynamic conditions, whereas flow separation at high intensities substantially lowers the wave energy dissipation. Conversely, <em>oyster reefs maintain wave energy dissipation across a broader hydrodynamic range due to the sharp-edged, rigid shells</em>. The enhanced wave attenuation by <em>oyster</em> reefs and their expected long-term persistence in the Wadden Sea presents an opportunity to complement existing gray coastal protection infrastructure as a nature-based solution. The parameterization of frictional wave energy dissipation presented here enables more accurate hydro-morphodynamic modeling of large-scale sediment dynamics in such soft-bottom environments.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104763"},"PeriodicalIF":4.2,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-16DOI: 10.1016/j.coastaleng.2025.104762
WoongHee Jung , Alexandros A. Taflanidis , Norberto C. Nadal-Caraballo , Luke A. Aucoin , Madison C. Yawn
{"title":"Advances in spatiotemporal storm surge emulation: database imputation and multi-mode latent space projection","authors":"WoongHee Jung , Alexandros A. Taflanidis , Norberto C. Nadal-Caraballo , Luke A. Aucoin , Madison C. Yawn","doi":"10.1016/j.coastaleng.2025.104762","DOIUrl":"10.1016/j.coastaleng.2025.104762","url":null,"abstract":"<div><div>Surrogate models, also known as metamodels or emulators, have emerged as a valuable tool for storm surge hazard estimation. They are developed using numerical model results from a database of synthetic storms and have the potential to provide highly-accurate and efficient surge predictions for new storms beyond those in the database. Frequently, metamodels need to provide spatiotemporal predictions for the storm surge evolution over time, across a large geographic domain represented through appropriately chosen save points (SPs). This paper focuses on a specific type of metamodel, Gaussian process (GP) emulation, that has been proven versatile in past studies for this specific application. The development of the spatiotemporal metamodel in this setting may involve: (a) an imputation step to fill in missing data, associated with instances that nearshore and onshore SPs are dry; and (b) a dimensionality reduction step for projection to a latent space to improve the computational efficiency for the metamodel calibration and predictions. Advances are established across both these aspects by treating spatiotemporal storm surge responses as a three-dimensional tensor (across storm, time, and spatial domains), and by integrating techniques designed specifically for this tensor structure. For data imputation, low-rank tensor completion (LRTC) is adopted. LRTC leverages response correlations across all tensor dimensions, leading to improved imputation performance compared to established alternatives (for example, geospatial interpolation), by ensuring time-series smoothness between the imputed data and the available data in the original database. A combination of LRTC with imputation based on geospatial interpolation is also discussed. As a dimensionality reduction technique, higher-order singular value decomposition (HOSVD) is applied to separately reduce the spatial and temporal dimensions of the database, enabling the preservation of principal information associated with response correlation separately from each dimension within the latent space. Compared to the past use of principal component analysis for the augmented spatiotemporal dimensions, the separation promoted through HOSVD improves the latent output ability to capture complex surge variations, accommodating higher prediction accuracy for the metamodels developed based on this enhanced latent output structure. To improve efficiency in the metamodel calibration, different strategies are examined for grouping the HOSVD-based latent outputs. Beyond advancements associated with the metamodel development, the improvement in accuracy of the predicted surge time-series around its peak is also considered by introducing a correction step using predictions from a supplementary metamodel developed to strictly predict the peak-surge. The proposed advances are demonstrated using the Coastal Hazards System–North Atlantic (CHS-NA) database.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"201 ","pages":"Article 104762"},"PeriodicalIF":4.2,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144138772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-14DOI: 10.1016/j.coastaleng.2025.104750
Björn R. Röbke , Hesham Elmilady , Mónica Aguilera Chaves , Marcel Taal , Mick van der Wegen
{"title":"The relative impact of sea level rise and dredging strategies on the morphodynamic evolution of the Western Scheldt estuary (The Netherlands)","authors":"Björn R. Röbke , Hesham Elmilady , Mónica Aguilera Chaves , Marcel Taal , Mick van der Wegen","doi":"10.1016/j.coastaleng.2025.104750","DOIUrl":"10.1016/j.coastaleng.2025.104750","url":null,"abstract":"<div><div>Worldwide, estuaries face challenges related to climate change and human interventions. The objective of this study is to gain insight into the relative impact of (extreme) sea level rise (SLR), dredging and disposal (DAD) activities and coastal nourishments on the century timescale hydro- and morphodynamic behaviour of the Western Scheldt estuary (i.e. the Dutch part of the Scheldt river). For this, we apply a two-dimensional process-based numerical morphodynamic model including wave action (Delft3D<!--> <!-->4), that allows for detailed analyses of the changing hydro- and morphodynamic conditions under various scenarios.</div><div>Scenario simulations for the period 2020–2100 are carried out based on downscaled SLR and tidal projections from a global tide model. Our model results suggest that SLR causes more resonant behaviour of the tidal wave and leads to less flood or increased ebb dominance throughout the estuary. Morphodynamic development lags behind SLR, which decreases intertidal area, changes the tidal asymmetry and enhances export or decreases import of sediment in the Western Scheldt. Excluding morphodynamic change in the model drowns the intertidal area even faster. Regarding possible sediment management strategies, the model indicates that the SLR induced enhanced sediment export trend can be locally counteracted by disposing a larger portion of dredged material in the more upstream parts of the estuary and/or by performing nourishments in the mouth area.</div><div>Our study shows the potential of using process-based models for SLR impact studies in estuaries albeit that more robust conclusions can be drawn when combined with other modelling approaches. Future work may improve hindcast and forecast efforts by using a three-dimensional modelling approach, adding mud dynamics and applying a more advanced wind, wave and DAD schematisation.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104750"},"PeriodicalIF":4.2,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143887175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-13DOI: 10.1016/j.coastaleng.2025.104752
Salomé Frugier , Rafael Almar , Erwin Bergsma , Alice Granjou
{"title":"SBI: A sandbar extraction spectral index for multi-spectral satellite optical imagery","authors":"Salomé Frugier , Rafael Almar , Erwin Bergsma , Alice Granjou","doi":"10.1016/j.coastaleng.2025.104752","DOIUrl":"10.1016/j.coastaleng.2025.104752","url":null,"abstract":"<div><div>Satellite imagery allows for large-scale monitoring of dynamic coastal processes, with shoreline tracking being the most widespread application. Nearshore wave-generated sandbars influence coastal dynamics by acting as natural buffers that reduce beach erosion through wave energy dissipation and sediment exchange with the aerial beach. Despite their importance, they are often overlooked in satellite-based studies. This paper addresses this oversight by introducing the SandBar Index (SBI), a new methodology designed to optimize the detection of wave breaking pixels induced by the underlying sandbar while minimizing the SBI value pixels from the surrounding environment such as sand, land and water. Wave breaking pixels refer to image pixels where breaking waves generate foam, increasing reflectance in optical satellite imagery. Since wave breaking typically occurs over submerged sandbars, these pixels act as proxies for their detection. By integrating this index into an automated processing framework, long-term time series of sandbar positions are generated alongside shoreline positions. To validate our methodology, Sentinel-2 images are used to compare satellite-derived sandbar positions with in-situ bathymetric data from the Field Research Facility (FRF) in Duck, North Carolina (US), over a period of nearly ten years. Validation results show good agreement (STD <span><math><mo>=</mo></math></span> 23.2 m - i.e. 2 Sentinel-2 pixels), demonstrating the ability of the method to capture the onshore and offshore migration of sandbars. The flexibility of the SBI allows implementation on different satellite platforms, including Landsat and VEN<span><math><mi>μ</mi></math></span>S, demonstrating its transferability. This application lays the groundwork for future studies using over 40 years of historical satellite data to further investigate long-term sandbar dynamics, but also high-frequency dynamics with the concomitantly increasing revisit and resolution of satellite missions. The integration of multiple observable metrics from satellite data allows for a more nuanced characterization of the coastal system as a dynamic entity.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104752"},"PeriodicalIF":4.2,"publicationDate":"2025-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143845315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-12DOI: 10.1016/j.coastaleng.2025.104756
Alvise Benetazzo , Filippo Bergamasco , Francesco Barbariol , Maurizio Ferla , Gabriele Nardone , Arianna Orasi , Marco Picone , Alex Stevanin , Andrea Marchitiello , Thomas Pavan , Mauro Bastianini , Mara Pistellato , Luigi Cavaleri
{"title":"Evaluation of the 3D response and performance of an operational wave buoy for coastal wave monitoring","authors":"Alvise Benetazzo , Filippo Bergamasco , Francesco Barbariol , Maurizio Ferla , Gabriele Nardone , Arianna Orasi , Marco Picone , Alex Stevanin , Andrea Marchitiello , Thomas Pavan , Mauro Bastianini , Mara Pistellato , Luigi Cavaleri","doi":"10.1016/j.coastaleng.2025.104756","DOIUrl":"10.1016/j.coastaleng.2025.104756","url":null,"abstract":"<div><div>This study analyzes the <em>in situ</em> 3D response and performance of a large, moored, accelerometer-based wave buoy designed for the new Italian buoy network. Deployed in coastal waters near an oceanographic tower in the North Adriatic Sea, the buoy's capability to follow wave motion was evaluated against a stereo-imaging system and a wave gauge. By employing a novel optical system based on stereo view, the 3D buoy displacement (vertical and horizontal motions) was measured, providing insights into buoy dynamics and enabling comparison with the onboard wave sensor. Measurements indicate good agreement between buoy heave and wave elevation in a narrow frequency band of 0.15–0.60 Hz, except around 0.52 Hz, which represents the buoy's natural frequency. Performance degradation at low and high frequencies was attributed to sensor processing as well as buoy and mooring responses, which were addressed by calibrating an empirical response operator for the buoy heave. Furthermore, a phase delay in horizontal motion was observed, likely caused by buoy inertia. For wave statistics, while the buoy effectively captures linear waveforms, it shows reduced sensitivity to second-order nonlinear effects due to its dynamic response, impacting the ability to observe maximum wave elevations. Despite these limitations, buoy data reliably estimate significant wave height and mean wave direction. This study enhances the understanding of moored buoy dynamics and aids in optimising buoy response for coastal wave monitoring.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104756"},"PeriodicalIF":4.2,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143873502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coastal EngineeringPub Date : 2025-04-11DOI: 10.1016/j.coastaleng.2025.104755
Zhiheng Yang , Xiaojing Niu
{"title":"Sequential characteristics of tropical cyclone induced winds, surges, currents and waves","authors":"Zhiheng Yang , Xiaojing Niu","doi":"10.1016/j.coastaleng.2025.104755","DOIUrl":"10.1016/j.coastaleng.2025.104755","url":null,"abstract":"<div><div>Tropical cyclones are common meteorological disasters around Hainan Island. The tropical cyclone induced wind, storm surge, strong currents, and large waves can impose cyclic loads on the foundations of offshore wind turbines, transoceanic bridges and other structures, leading to structural fatigue and even failure. Understanding the sequential characteristics of these dynamic factors are beneficial for better simulating the structural response. This paper studies 807 independent tropical cyclones from 1949 to 2022 through numerical reconstruction. Based on statistics, the paper proposes the duration peak profiles of tropical cyclone induced wind, surge, current and wave. It is found that there are time lags between the profiles' peaks, and are distributed regularly across the sea area. The research shows that storm surges and large waves usually occur ahead of the front of tropical cyclones about 1 h, but the sheltering effect of islands could significantly influence the time lags of storm surges and large waves. Strong currents typically lag behind strong winds, and the time lag of strong currents is complex due to the influence of topography.</div></div>","PeriodicalId":50996,"journal":{"name":"Coastal Engineering","volume":"200 ","pages":"Article 104755"},"PeriodicalIF":4.2,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}