Dredging and excavation activities on fringing reefs have potential impacts such as the coastal inundation during extreme wave events, and no published laboratory experiments have addressed this issue. To verify the previous findings from both field observations and numerical simulations, and focus on evaluating the alteration of wave processes over fringing reefs by an excavation pit, a new set of

A laboratory and numerical investigation on the features of the horizontal and vertical hydrodynamic loads given by a solitary wave on a submerged square barrier is presented. By the experimental viewpoint, the wave forces were deduced from the records of a discrete battery of pressure sensors located along the external surface of the barrier. As regards the numerical viewpoint, simulations were performed

In extreme storm conditions, a levee would be subject to a combination of wave overtopping and surge overflow, namely combined wave and surge overtopping, which is easier to induce catastrophic levee failures than common wave overtopping. One of the significant differences between combined wave and surge overtopping and wave overtopping is that downward-flushing flows are formed on the levee crest

Coastal erosion is driven by both a storm’s erosion potential and by an area’s vulnerability. Therefore, the problem of estimating impacts can be approached in two-step. The first includes an assessment of erosion potential based on readily available storm parameters, while the second combines this information with highly localized parameters, describing vulnerability, to more directly predict local

This research focuses on the development of a simple and efficient transect based long-term shoreline model. The new modeling tool is a combination of a model for the shoreline changes due to the gradients in longshore drift and a heuristic cross-shore shoreline model. The cross-shore part of the model uses an up-to-date semi-empirical shoreline evolution model based on the equilibrium beach state

The assessment of extreme significant wave heights is crucial for the design of coastal defences and offshore infrastructures, which requires independent and identically distributed samples to be extracted. To extract independent samples at the regional scale, an automated method is proposed by extending an observational method. In addition to the initial threshold, a minimum interval is used to identify

The stability evaluation of artificial submarine slope under wave load is a primary concern in the construction of offshore structures such as submarine pipelines and immersed tunnels. Aiming at this issue, an integrated Finite Element Method (FEM) model of wave-seabed interaction is proposed to investigate the effects of wave action on the wave-induced slope stability of the temporary trench. The

The aim of this study is to determine the tsunami potential of the southern Turkish coast through hypothetical earthquake scenarios developed for several critical coastal sites in the region. A well-known tsunami numerical model (MOST) is utilized to calculate the run-up and inundation of the subsequent tsunami waves. The coastal regions selected to realize the aim of the study are Akkuyu and Yeşilovacık

We study the swash flow driven by breaking waves of elevation using two sets of large-scale experiments with a focus on understanding how wave properties control the flow evolution on the beach In the first set of experiments, we test solitary waves and waveforms that have the same acceleration phase and wave height as the solitary waves, but an elongated deceleration phase. The results show that the

The wave-attenuation performances and hydrodynamics of moored box-type floating breakwaters with the same weight, same wall thickness, and six different cross-sections, i.e. circular, triangle-down, triangle-up, rectangular, trapezoid-down, and trapezoid-up, are investigated numerically using the smoothed particle hydrodynamics (SPH) method. Coupling between DualSPHysics and MoorDyn is implemented

Previous studies demonstrated an introduction of building opening could decrease the tsunami loads on the external wall. However, tsunami waves flowing through the building opening could induce loads on the interior part. This study presented an experimental investigation of tsunami flow through a real building with opening. Three nominal wave conditions with wave overtopping and non-overtopping cases

In coastal engineering context, the use of video imagery is widespread. Especially in field settings along sandy coasts, many types of data have been derived from video imagery, often using non-learning analysis techniques. Recent advances in the field of computer vision and deep learning allow for the automation of image segmentation. In this paper, these techniques are combined with video imagery

In this paper, the cross-shore propagation and shoaling of bound infragravity (IG) waves have been investigated. By establishing a conceptual 1D model utilizing a constant slope in the shoaling zone, a semi-analytical solution for bound IG waves could be obtained. Through the use of this semi-analytical solution, a collection of bichromatic conditions have been simulated, thus confirming the dependence

The main objective of this research is to characterize and quantify the prevalent physical processes in the energy transformation of a regular wave train when it interacts with permeable and impermeable breakwaters. Two sources of experimental data are considered: (a) numerical experiments on an undefined impermeable rigid slope, using the numerical model (IH–2VOF), and (b) physical experiments on

A general framework for wave separation in the frequency domain is presented and evaluated with successful results using theoretical examples of nonlinear waves. This framework consists of a qualitative and a quantitative analysis. The qualitative analysis is a novel approach that provides useful information about the existing wave trains within a wave field. This information includes an estimation

Barrier islands are susceptible to erosion, overwash, and breaching during intense storms. However, these processes are not represented typically in large-domain models for storm surge and coastal inundation. In this study, we explore the requirements for bridging the gap between dune-scale morphodynamic and region-scale flooding models. A high-resolution XBeach model is developed to represent the

Coastal dunes can provide protection from flooding during extreme weather events. As such, consideration should be given to strengthening the protective mechanisms of dunes. Vegetation has recently been seen as an important factor influencing erosion processes on dunes. Another means of dune reinforcement is the installation of internal structures within dune systems. The purpose of this work is to

We present the experimental analysis of the interaction between wind waves and currents, during the generation process, through laboratory experiments in a wind-waves-current tunnel. The objective is the quantification of the effects of a co-/counter-current on the main characteristics and statistical estimators of the wave field. Twenty-two experiments were performed with two different wind speed

Sand nourishments are increasingly applied as adaptive coastal protection measures. Predictions of the evolution of these nourishments and their impact on the surrounding coastline contain many uncertainties. The sources that add to this uncertainty can be delineated between intrinsic and epistemic uncertainty, i.e. inevitably in the system or related to knowledge limitations. Effects of intrinsic

The analysis of damage in rubble mound scour protections is crucial for the armour stability assessment. Former methodologies focused on the analysis of the maximum damage number. This work introduces a complementary methodology to determine and characterize damage statistical distribution based on a flexible arrangement of sub-areas. The sub-areas are overlapping and can be varied in size, allowing

Focused wave groups are traveling waves characterized by extremely-large transient wave amplitudes and very short durations. These waves usually cause serious damage to marine/offshore structures and coastal infrastructures, and can even result in human casualties (Nikolkina and Didenkulova, 2011). The studies on natural disasters related to the focused wave groups near the coastal zone have been mostly

Existing empirical and theoretical models for swash overtopping are considered and reconciled by using the positive volume flux of the incident waves and deficit in freeboard as scaling parameters. This scaling holds for solitary waves, monochromatic waves and random waves. The empirical model of Battjes (1974a), the EurOtop model (EurOtop, 2016) and the theoretical model of Peregrine and Williams

We present the development of a high-efficiency and high-resolution subgrid model for simulating surface water and groundwater interaction in coastal regions. The governing equations are derived based on an assumption of the fully-saturated subsurface flow and a phase-averaging method, in which two phase functions are defined respectively for the surface phase and subsurface phase at the subgrid level

The Tsunami-HySEA model is used to perform the five numerical benchmarks proposed in the “NTHMP/MMS Benchmarking Workshop: Tsunami currents”. Many different model configurations and sensitivity studies were performed for the different benchmarks, combining numerical methods of first, second, and third order, different friction laws, varying friction coefficients and numerical resolutions, or even different

Natural and man-induced coastal erosion endanger life and environment in coastal areas worldwide. For sedimentary barrier coasts, beach and underwater nourishments are an efficient coastal protection strategy. To optimize nourishments and to understand their impact on the marine environment, monitoring strategies are required. In this study, we investigate the potential of multibeam echosounder (MBES)

Although commonly used for the validation of morphological predictions, point-wise accuracy metrics, such as the root-mean-squared error (RMSE), are not well suited to demonstrate the quality of a high-variability prediction; in the presence of (often inevitable) location errors, the comparison of depth values per grid point tends to favour predictions that underestimate variability. In order to overcome

New large-scale experiments on the influence of storm sequencing on beach profile evolution are presented. The experiments comprised three sequences that commenced from the same initial beach profile. Each sequence consisted of two storms of different energy, with each storm followed by a recovery phase. A specific focus of the experiments was the influence of storm chronology as well as the influence

In this paper, we present measurements of force distribution on a vertical, circular cylinder exposed to shoaling regular waves. The cylinder was divided into four individual sections on which the wave loads were measured. Furthermore, we measured the wave kinematics with Particle Image Velocimetry (PIV) and with Laser Doppler Velocimetry (LDV) in a few reference cases. The force distribution was measured

WAVEWATCH III has been equipped with a new parallelization algorithm, domain decomposition and an optional implicit numerical scheme for coastal application at high spatial resolution with triangular unstructured grids, compatible with community-based coupling infrastructure. We performed a validation study for Hurricane Ike (2008) to prove the accuracy of the updated model against satellite altimeter

In this paper an Incompressible Smoothed Particle Hydrodynamics (ISPH) method solving the 2D RANS (Reynolds Averaged Navier-Stokes) equations with the k–ε turbulence closure is constructed. In the present model, the concept of “massless ISPH” utilizing the definition of “particle density” (number of computational particles within unit volume) is stressed. The skills of this numerical model are tested

The work highlights the importance of directional spreading effects on wave overtopping estimation in shallow and mild sloping foreshores. Wave short-crestedness leads, in general, to a reduction of mean overtopping discharges on coastal structures. In the present work, the case of a sea dike with gentle foreshore in very and extremely shallow water conditions is analysed. Physical model tests have

Estimation of the required armor size is a major task in the design of coastal structures under wave loading such as breakwaters and revetments. Several semi-empirical formulas have been developed for this purpose. However, these formulas are often either limited to certain water depth conditions or do not incorporate the permeability of the structure in an appropriate way. The main objectives of this

This study uses a machine learning algorithm, the bagged regression tree, to detect error patterns within 24-h forecasts of significant wave height time series. The input to the machine learning algorithm were bulk parameter outputs of the numerical wave model (WaveWatch III) and wind information from the Global Forecast System at buoy locations along the California-Oregon border in the United States

Vegetation can contribute to coastal defence by damping incoming waves. However, prior studies have shown that attenuation varies greatly among plant species. Plant flexibility is a mechanical property that is commonly omitted, but varies greatly between shrubs and grasses on salt marshes. Therefore, we present an experimental study in a laboratory wave flume with artificial vegetation that differs

Cross-shore profile response to energetic wave events is challenging to predict because the physics are poorly understood and wave and topographic data are often sparse or unknown. Six events with varying duration, wave intensity and beach slopes are used to calibrate and assess two process-based cross-shore models, CShore and XBeach, at two southern California beaches. Model performance is quantitatively

The Great Barrier Reef (GBR) coral coverage is in rapid decline from severe and sustained pressures from lagoon water quality, crown-of-thorns starfish (COTS), coral bleaching, tropical cyclones, pollution and diseases. The two recent GBR coral bleaching events (2016–2017) lead to Great Barrier Reef Marine Park Authority (GBRMPA) shifting their focus from passive management to active intervention (Great

Waveforms described by the second-order Stokes-type approximations are prone to display anomalous troughs with spurious negative crests. The systemic occurrence of such physically unrealistic features restricts the range of relative validity of second-order models and causes serious errors in modeling the statistics of sea-surface elevations, especially in intermediate and shallow water depths. As

Many rubble mound breakwaters are nowadays made with an armour layer consisting of single layer interlocking elements. The stability of these armour layers could well be influenced by the irregularity of the rock underlayer, as that influences the degree of interlocking. Especially for the new types of regularly placed armour, this might be an important factor for the stability. However, this aspect

Idealized bathymetries were subjected to idealized cyclones in order to measure the storm surge response to a range of shoals, under various storm conditions, for the purpose of informing the development of bathymetry thinning algorithms. Nine bathymetries were considered, including eight large, offshore shoals and a featureless reference domain. Six storm realizations (two different sizes/intensities

The spectrum of tidal and subtidal water level variations in river deltas responds river discharge variation, ocean tides, and human activities of many kinds. It remains a contemporary challenge to identify the main sources of changes in tidal dynamics in deltas, because of nonlinear interactions between tides and the river discharge in a changing setting. Understanding the main forcing factors controlling

An explicit approximation is proposed for velocity distribution and sediment flux above mobile sediment bed beneath current and asymmetric wave. The predicted velocity is decomposed into an oscillatory part and a current part such that the interaction between current and asymmetric wave can be performed directly. The oscillatory part consists of a free stream velocity and a defect function which includes

Reshaping berm breakwaters have been mainly designed and built for water depth less than 20 m. In such conditions, a toe structure may be needed to reduce bottom settlements and increase geotechnical stability in the loose subsoil condition. Also, a toe berm can be deployed to reduce the berm recession and increase the stability of the Reshaping berm breakwater, especially in deep water. Although many

The generation of stable and pure solitary waves in large-scale experimental flumes and numerical models is the focus of this study. Such waves give a better description of the target wave amplitude, has minimal amplitude dissipation during propagation and has negligible trailing waves. In the present study, the two solitary wave generation methodologies, namely, Goring's Method (GM) and the Malek-Mohammadi

Foreshores consisting of both bare tidal flats and vegetated salt marshes are found worldwide and they are well studied for their wave attenuating capacity. However, most studies only focus on the small scale: just some isolated locations in space and only up to several years in time. In order to stimulate the implementation of foreshores serving as reliable coastal defense on a large scale, we need

The present paper investigates the short-term statistical distribution of wave heights. Specifically, a large number of the most commonly applied wave height distributions are assessed using field measurements. The latter comprise of wave radar observations from 10 different locations in the North Sea and cover water depths between 7.7 m and 45 m. In total, the field database includes more than 200

Hazard assessment is one of the key elements to be included in any coastal risk assessment framework. Characterizing storm-induced erosion and inundation involves the assessment of the coastal response under the forcing of a stochastic source (the storm), acting on a variable morphology (the beach) and inducing some damages. Hazard assessment under any present or future scenario will be affected by

This paper presents a model for the evaluation of long waves amplification at coastal areas, based on a modal decomposition method. It is able of modelling the growth and the decay of the natural modes of the area under investigation, and their contribution to the total wave field. The model is an improvement of that developed by Bellotti et al. (2012b), that was able of calculating the frequencies

A numerical model of scour beneath subsea structures considering the effect of upward seepage in the seabed is proposed. A small seepage can cause significant changes to the hydrodynamic force on the bed surface and stability of bed particles, which can further affect the sediment transport processes and scour patterns around subsea structures. The present model is developed based on a fully-coupled

In this second of two papers, the high spatial resolution cBathy depth estimate algorithm is extended to account for the existence of currents aligned with the wave directions. The extended algorithm is applied using X-band radar image time series collected at two hydrodynamically and morphologically complex environments: an ebb-tidal shoal (New River Inlet, NC) and an estuarine river mouth (Columbia

Debris-flow generated tsunamis can be extremely dangerous for lakeside settlements and infrastructure. Debris-flow composition strongly affects debris-flow thickness and velocity, and therefore also the generated tsunami. This interaction is, however, poorly understood. We investigate the effects of debris-flow volume, composition (gravel, sand, clay, water) and subaerial outflow slope on wave celerity

A previously developed research-grade (e.g. high-resolution) unstructured mesh of the northern Gulf of Mexico (named NGOM3) is optimized to produce a computationally efficient forecast-grade mesh for deployment in a real-time hurricane storm surge early warning system. The real-time mesh is developed from a mesh decimation scheme with focus on the coastal floodplain. The mesh decimation scheme reduces

This paper presents a new approach to statistically characterize and simulate the wave climate under storm conditions. The methodology includes the joint selection of the parameters that identify storm events (significant wave height threshold, minimum storm duration and minimum interarrival time between consecutive storms) by means of hypothesis testing on the distribution functions of the number

Two-dimensional (2D) local scour beneath two submarine pipelines in tandem under wave-plus-current conditions is investigated numerically. A fully-coupled hydrodynamic and morphologic model based on unsteady Reynolds-averaged Navier-Stokes (URANS) equations with the k−ω turbulence closure is applied. The model is validated against existing experimental measurements involving live-bed scour beneath

On October 29, 2012, storm surge and large waves produced by Hurricane Sandy resulted in the formation of a breach in eastern Fire Island, NY. The goals of this study are to gain a better understanding of the physical processes that govern breach behavior and to assess whether process-based models can be used to forecast the evolution of future breaches. The wilderness breach grew rapidly in size during

The effects of reef permeability on the spatial distributions of wave-induced current inside and outside the inhomogeneous coral reef body are investigated using an improved weakly compressible smoothed particle hydrodynamic (WCSPH) mixture model. The governing equations are formulated based on the two-phase mixture theory without considering the solid phase motion in terms of the intrinsic velocity

Predicting the propagation and transformation of the solitary wave is very important in coastal engineering. This paper presents a numerical investigation of the solitary wave breaking over a slope by using a finite particle method (FPM), which is an enhanced smoothed particle hydrodynamics (SPH). We firstly conduct a comparative study on SPH and FPM in modelling solitary wave and it is demonstrated

Many harbor applications are based on the solution of linear elliptic agitation problems for many spectral conditions. One of the main goals consists in computing the linear combination of numerous simulations of the harbor agitation problem, using monochromatic waves of different spectral components (i.e. frequency and incoming wave direction). In practice, the standard strategy selects the number

A reliable estimation of average wave overtopping discharge is important for dike design and safety assessment. Berms and roughness elements are widely applied to reduce the overtopping discharge over dikes. In this study, the effects of a berm and roughness on the wave overtopping discharge are investigated by means of physical model tests. New empirical formulae are derived from the analysis of the

Future investments required for the construction and maintenance of coastal defense interventions are expected to increase, due to increasing coastal erosion issues along social, environmental and economically valuable coastal areas. The high costs related with coastal defense interventions require improved knowledge on their performance, considering impacts, costs and benefits. Despite the existence

The southeast coastline of the Barents Sea in the area of the Varandey settlement is characterized by warm permafrost. Coastal studies conducted since the early 1980s have shown coastal retreat with average erosion rates of up to 2–5 m/yr from 1969 to 1987 at different locations in the area. The present study summarizes long-term (1951–2013) observations of environmental forcing in the area, and estimations