bluuebunny/crossref_metadata_2025 huggingface dataset:
ASSESSMENT OF THE EFFECTS OF THE ZUIDER SEA CLOSURE ON THE HYDRODYNAMICS OF THE WADDEN SEA INLETS
Authors: Vroom Julia , Elias Edwin , Lescinski Jamie , Wang Zheng Bing
Published: December 2012

Large hydrodynamic and morphodynamic changes have taken place in the western Dutch Wadden Sea due to the closure of the Zuider Sea in the early 1930s. Hydrodynamic simulations for three situations, viz. just before the closure, just after the closure and at present, have been carried out in order to investigate the hydrodynamic changes since the closure and to improve our understanding of the observed morphodynamic changes. The model results show a large increase in tidal range after the closure of the Zuider Sea. This increase continued to grow after the closure due to bathymetric change and sea level rise. The morphodynamic analysis focuses on the changed behavior of the ebb-tidal deltas of the Texel Inlet and the Vlie Inlet. Both ebb-tidal deltas have undergone a re-orientation in up-drift direction. Two possible explanations based on the literature for this change are discussed with the help of the hydrodynamic simulations.
INCREASED WATER LEVELS DUE TO MORPHODYNAMIC CHANGES; THE LIMFJORD, DENMARK
Authors: Knudsen Soeren Bjerre , Ingvardsen Signe M. , Madsen Holger Toxvig , Sorensen Carlo , Christensen Bo Brahtz
Published: December 2012

The Limfjord is an estuary in Denmark between The North Sea and Kattegat. The Thyboroen Channel connects the fjord with The North Sea. The water levels in the western part of the Limfjord are strongly correlated with the water level in the sea at Thyboroen. Analyses revealed a close to threefold increase in the channel cross section over the last 100 years. This has led to a detailed investigation into the effects of the channel cross section on the extreme high water levels in the Limfjord now and in the future. For Lemvig in the western part of the Limfjord the water level with a return period of 100 years would have been 1.73 m with the 1958 channel bathymetry throughout the whole period and 1.99 m with the 2005 channel bathymetry. With the extrapolated 2060-bathymetry the 100 years water level will be 2.38 m. A number of measures to counteract the consequences of this development have been evaluated.
FUTURE EXTREME WAVES AT THE GERMAN BALTIC SEA COAST DERIVED FROM REGIONAL CLIMATE MODEL RUNS
Authors: Schlamkow Christian , Dreier Norman , Fröhle Peter , Salecker Dörte
Published: December 2012

Information about possible changes of extreme wave heights are essential for the future safe design of coastal and flood protection structures likes dykes, flood protection dunes, revetments etc. In this study, scenarios of regional climate change up to 2100 are used for the evaluation of changes of wave conditions. Analyses on calculated significant wave heights derived from extreme value statistics are showing a different signal of change for the selected locations along the German Baltic Sea Coast. The results are showing that extreme wave heights with a return level of 200 years can increase up to +14%. But also a decrease of down to -14% were found compared to actual conditions, depending on the location and climate change scenario applied. At the location of Warnemunde a slight increasing trend for the change of extreme wave heights could be found for 3 of 4 scenario runs with a maximum increase of +7%.
MODELLING ANTHROPOGENIC EFFECT OF A TIDAL BASIN EVOLUTION
Authors: Dissanayake Pushpa Kumara , Wurpts Andreas , Miani Marco , Knaack Heiko
Published: December 2012

A numerical approach was undertaken to investigate an anthropogenic effect (i.e., construction of a peninsula in 1984) on the tidal basin evolution of the Ley Bay in the East Frisian Wadden Sea. Coupled hydro-morphodynamic model runs span from 1975 to 1990 applying both tidal and wave boundary forcings with a multiple-sediment bed. The offshore tidal force was transformed to the study area applying a cascade modeling approach while a highly schematised wave climate was adopted in this simulation. Two bathymetries (i.e., 1975 and 1990) were available for this study and therefore the peninsula was implemented based on the 1984 predicted bed. Resulting morphodynamic evolution indicates that the deeper areas (channels) are well reproduced by the model rather than the shallow areas (inter-tidal areas). In addition to the peninsula construction, the human interference by dredging and dumping appears to have influenced the Ley Bay evolution. Due to the lack of data availability, such information was not incorporated in this study. Comparisons of predicted and measured 1990 topographies in terms of qualitative and quantitative parameters show that the predicted bathymetry sufficiently resembles with the data. Application of a highly schematised wave climate affects on the bed evolution. Further investigation on the wave schematization could help to optimize the model prediction. On-going work uses this model set-up in order to forecast the Ley Bay evolution under future sea level rise scenarios.
DAMAGE TO REINFORCED CONCRETE BUILDINGS AND COASTAL TREES DUE TO THE 2011 OFF THE PACIFIC COAST OF TOHOKU EARTHQUAKE TSUNAMI
Authors: Matsutomi Hideo , Yamaguchi Eriko , Naoe Kazunori , Harada Kenji
Published: December 2012

Macroscopic conditions of the damage to RC building and coastal black pine tree in the 2011 Off the Pacific Coast of Tohoku Earthquake Tsunami are discussed through field surveys and field tests. Effects of RC building's location and arrangement, submerged vertical section area in the tsunami inundation flow direction, ratio of the area of submerged windows and/or doorways to the area of submerged vertical wall on the side hit by the inundation flow (so-called, aperture ratio), and foundation piles on the damage condition of the building are examined. The damage condition of the coastal tree is also discussed from the viewpoints of the drag force and moment assessed using inundation flow velocity estimated by a simple method. Moreover, effects and limits of coastal woods on the tsunami energy and force reductions are illustrated through the field surveys.
MODELLING STORM IMPACT ON COMPLEX COASTLINES. WESTKAPELLE, THE NETHERLANDS
Authors: Santen Robbin van , Steetzel Henk , Van Thiel de Vries Jaap , Dongeren Ap van
Published: December 2012

Regular dune safety assessments in the Netherlands are presently based on a 1D model approach, which is insufficiently applicable for more complex coastal areas with structures, tidal channels or spatially strong varying bathymetry. These situations require more advanced methods to assess the safety in dune areas. In this study a 2DH XBeach model (Roelvink et al., 2009) is applied as a demonstration for a complex coast, and a comparison is made with results obtained from a 1D model approach, using 1D XBeach and 1D DurosTA (Steetzel, 1993). For this specific test-case the coastal area near Westkapelle (in the south-western part of the Netherlands) is selected, since this location is considered to be 'complex' for regular safety assessment studies. The near-shore zone is characterized by a (spatially) strongly varying bathymetry, due to the presence of tidal flats and channels, and a strongly curving coastline. Moreover, the Westkapelle-area is protected by both coastal structures and sandy dunes, such that transition zones exist, which are difficult to assess with a 1D model approach. It is demonstrated that a 2DH model approach enables detailed analysis of the effect of alongshore processes on (dune-) erosion. From model comparisons it is concluded that significant differences are found between simulated erosion-volumes for 1D and 2DH models, when considering the impact of normative storms on complex coastlines.
APPLICATION OF AN AUTONOMOUS ROBOT FOR THE COLLECTION OF NEARSHORE TOPOGRAPHIC AND HYDRODYNAMIC MEASUREMENTS
Authors: Wubbold Frauke , Hentschel Matthias , Vousdoukas Michalis I. , Wagner Bernardo
Published: December 2012

Beach topographic and hydrodynamic measurements are essential for coastal geology and engineering studies as well as sustainable coastal management. Standard approaches involve either time-consuming manual data acquisition usually with limited coverage or remote sensing techniques which are usually characterized by low resolution or increased costs. The present contribution reports the results from the application of the autonomous robot RTS-Hanna with a calibrated sensor setup including 3D laser range scanners, a camera, a Differential GPS and an inertial measurement unit which significantly facilitates field data collection. RTS-Hanna was tested at the Wadden Sea Barrier Island Langeoog, Northern Germany, for two days and was proven capable of autonomously collecting topographic scans. 175 GB of dense topographic and water surface elevation data were collected, including RBG images, while RTS-Hanna covered a total of 21 km of coastline in approximately 3 hours. Scans of the surf/swash zone allowed continuous measurements of topographic changes at the beachface, wave propagation velocities and wave breaking heights.
STORM EARLY WARNING SYSTEM AS A LAST PLUG-IN OF A REGIONAL OPERATIONAL OCEANOGRAPHY SYSTEM: THE CASE OF THE GULF OF CADIZ
Authors: Plomaritis Theocharis A. , Benavente Javier , Del Rio Laura , Reyes Emma , Dastis Carlos , Gomez Marta , Bruno Miguel
Published: December 2012

The implementation of an Early Warning System for storm impacts in the urban beach of Cadiz is presented. The model train is described in detail together with the downscaling procedure. Emphasis is given on how the morphodynamic model receives the necessary information from the regional operational oceanography system specifically developed for the Gulf of Cadiz. The translation of the morphodynamic model output into useful information for the civil protection and other responsible authorities is provided based on the coastal state indicator approach. All the intermediate and final results are presented in a purpose-based on-line application.
METHODS AND ANALYSIS TOOLS FOR REDEVELOPMENTS IN AN ESTUARY WITH HIGH SUSPENDED SEDIMENT CONCENTRATIONS
Authors: Donner Monika , Ladage Florian , Stoschek Oliver , Nguyen Hoang Ha
Published: December 2012

One of the largest estuaries in Germany, the Ems estuary, identified a dramatic turbidity increase up to more than 10 g/l over the last years. Due to this fact ecologists and water management authorities try to find restoration measures, which are able to reduce suspended sediment concentrations and to increase oxygen supply. The assessment of these potential restoration measures is described in the following paper and is based on a highly resolved numerical representation of the present situation of the Ems with extreme high turbidities by including effects of flocculation and hindered settling. Therefore two different approaches for the settling velocity due to flocculation were compared. An analysis of these restoration measures delivers important findings and shortcomings of each measure. Finally the restoration potentials are quantified by key indicators for hydrodynamics and suspended sediment transport behavior and were evaluated due to their relevance in reduction of high turbidities.
WAVE - INDUCED DEVICES FOR THE OXYGENATION OF DEEP LAYER: A PHYSICAL INVESTIGATION
Authors: Antonini Alessandro , Gaeta Maria Gabriella , Lamberti Alberto
Published: December 2012

No other environmental variable of ecological importance to estuarine and coastal marine ecosystems around the world has changed so drastically, in such a short period of time, as dissolved oxygen. Coastal surveys in United States and Europe found that a staggering 78 % of the assessed continental U.S. coastal area and approximately 65 % of Europe's Atlantic coast exhibit symptoms of eutrophication. The 65 % of the coasts counted by Diaz does not take into account inland seas like the Adriatic or Baltic Seas but also for these, eutrophication and consequently anoxia are common problems. In the present study a simple and economic device is proposed to enhance vertical mixing processes and to induce aeration of deep water by pumping of oxygen-rich surface water downwards to a desired depth around the halocline. The hydrodynamic parameters of the device are estimated through free oscillation tests. Preliminary values of the downward water flux velocity inside the device and the movements of the floater under the action of 4 regular waves, characterizing of the wave climate in the Nord Adriatic Sea, are estimated.
ARTIFICIAL DEVIATION OF A SMALL INLET (BEVANO, NORTHERN ITALY): PREDICTION OF FUTURE EVOLUTION AND PLANNING OF MANAGEMENT STRATEGIES USING OPEN-SOURCE COMMUNITY COASTAL MODELS
Authors: Ciavola Paolo , Tondello Massimo , Carniel Sandro , Sclavo Mauro
Published: December 2012

The Bevano river flows into the northern Adriatic Sea in a microtidal-low energy wave environment. The river mouth was diverted artificially in 2006 to contrast dune erosion and decrease inland river flooding. The intervention can be considered as a low impact one as the engineering works were constructed in timber and the possibility of the inlet naturally changing its course was contemplated. An ensemble of hydraulic/morphological scenarios was simulated using data from field surveys and a coupled numerical model. The aim of the modeling was to understand the morphological changes caused by extreme hydro-meteorological events and the relationships between the inlet and the adjacent beaches. Additionally, the probability of a second inlet opening either by overwashing or river breaching was another important topic considered for management purposes. The modeling found that, a second inlet can actually be opened under a 30 year flood occurring without any significant wave action. For other conditions, the current inlet will be the main source of water escape at sea. Finally, the modeling results confirmed the dominance of the ebb tide in creating a small ebb delta/swash bar, with many similarities with other inlets exposed to a larger tidal range. Currently the management strategy by competent authorities is a minimum maintenance option, with yearly repairs of the timber structures.
VESSEL WAKE INDUCED SEDIMENT MOBILITY AT EAGLE HARBOR, WASHINGTON, USA
Authors: Michalsen David , Demirbilek Zeki , Nwogu Okey
Published: December 2012

Eagle Harbor is a small natural harbor located in central Puget Sound on the eastern side of Bainbridge Island, Washington State, USA. Over a period of about 80 years, the harbor was severely contaminated. Approximately 28.3 hectares of the contaminated harbor were capped with dredged and upland sediments from 1993 to 2008. Recent monitoring data has concluded portions of the subtidal cap has eroded and may not be physically stable. Erosion in the vicinity of the car passenger ferry sailing line suggests the cap material may not be of sufficient size to achieve the objectives of providing a physical barrier for chemical isolation. Here, a two-dimensional finite difference model using a coupled Boussinesq-Panel method is used to investigate bed shear stresses on the existing sediment cap to analyze cap stability. Model results indicate the subtidal cap experiences over 100 Pa of bed stress within a 30 meter swath of the ferry sailing line. These bed stresses significantly exceed the critical shear stress of the original cap material indicating the cap is not physically stable.
REDUCING UNCERTAINTY IN EXTREME WAVES AND STORM SURGES USING A COMBINED EXTREME VALUE MODEL AND WAVELETS
Authors: Galiatsatou Panagiota , Prinos Panayotis
Published: December 2012

In the present study the wavelet transform is combined with non-stationary statistical models for extreme value analysis, to provide more reliable and more accurate return level estimates. The continuous wavelet transform is first used to detect the significant "periodicities† of the wave height and storm surge signals under study by means of the wavelet global and scale-averaged power spectra and then it is used to reconstruct the part of the time series, represented by these significant and prominent features. A non-stationary point process is utilized to model the extremes. A time varying threshold with a period of one year and having an approximately uniform crossing rate throughout the year is used. The reconstructed part of the series variability representing the significant non-stationarities of each signal is incorporated in the both the location and the scale parameters of the point process model, together with selected harmonic functions, formulating a number of candidate extreme value models. The quality of the fitted models is assessed by means of the Akaike Information Criterion, as well as by means of diagnostic quantile plots. The models which incorporate the reconstructed part of the wavelet transform in their location parameter, as a separate component of the parameter without any scaling coefficient, result in narrower return level confidence intervals and therefore tend to reduce uncertainty in extrapolated extremes.
TO THE EFFECTIVENESS OF COASTAL AND FLOOD PROTECTION STRUCTURES UNDER TERMS OF CHANGING CLIMATE CONDITIONS
Authors: Froehle Peter
Published: December 2012

Consequences resulting from future Climate Change may be one of the most severe threats for people and economies in many countries of the world. Besides the problem of sea level rise, also possible general changes in the frequency and intensity of storms as well as general changes in the average wind field are expected for the future.

With respect to the coastal protection possible future strategies and also possible future measure are analyzed and assessed with the result that technical, morphological, socio-economic and aesthetical aspects play a role.
RELIABILITY ANALYSIS AND BREACH MODELLING OF SEA/ ESTUARY DIKES AND COASTAL DUNES IN AN INTEGRATED RISK ANALYSIS
Authors: Naulin Marie , Kortenhaus Andreas , Oumeraci Hocine
Published: December 2012

In order to quantify the risk of flooding, an integrated risk analysis is being performed within the German 'XtremRisK' project (Extreme storm surges at open coasts and estuarine areas: risk assessment and mitigation under climate change aspects) wherein one task is to analyze the reliability and breaching of flood defences. In this paper, the methods and results of the reliability analysis and the breach modelling of sea and estuary dikes and coastal dunes are discussed and applied to examples of the pilot sites of Hamburg (Elbe Estuary) and the Island of Sylt (North Sea). These results are put in context of an integrated flood risk analysis approach used in XtremRisK.
ASSESSMENT OF HYDRAULIC LOADS AND DERIVATION OF FAILURE PROBABILITIES AS A BASIS FOR THE DEERMINATION OF FRAGILITY CURVES FOR FLOOD DEFENCE DUNES
Authors: Gruhn Angelika , Salecker Dörte , Fröhle Peter , Schuttrumpf Holger , Thorenz Frank
Published: December 2012

Low lying coastal areas have always been preferred settlement areas as well as trading and industrial areas. Unfortunately, those areas are strongly endangered by extreme storm surges. In the event of a flood defence failure, protected areas are flooded and damages have to be expected. For the assessment and management of flood risk, the European Union approved the "Directive of the European Parliament and the Council on the assessment and management of flood risk†.
As one part of a risk and damage analysis the risk of flooding - being the product of failure probability of a certain flood defence and the damages resulting from a failure of this flood defence - has to be determined. One possibility for the assessment of the failure probability is provided by fragility curves. A method for the derivation of fragility curves for flood defence dunes is described. Hence, the applied dune erosion model as well as the method for the derivation of the required input data is explained. Furthermore, first results of the calculation of failure probabilities and fragility curves are presented.
A METHOD FOR THE SPATIAL ANALYSIS OF ANTHROPOGENIC PRESSURES IN SPANISH MARINE WATERS
Authors: Moreno Isabel , Del Barrio Irene , Lloret Ana , Pérez-Puyol Ainhoa
Published: December 2012

In 2008, the European Community adopted the Marine Strategy Framework Directive, aiming to achieve or maintain good environmental status in the European marine environment by 2020, applying an ecosystem-based approach to the management of human activities. Spatial information of the distribution of the human activities and their related pressures is essential to accomplish this task successfully. After compiling the available data from official sources, the spatial extent of the land-based and ocean-based human activities that could have an impact on the Spanish marine waters were estimated and mapped using GIS tools. In addition, a series of indexes were created in order to develop a cumulative analysis, taking into account the different relevance of pressures and that single pressures have different intensities. The identification of areas with an accumulation of pressures revealed that it is in coastal waters around big cities where the greater part of the pressures concentrates for each of the five Spanish marine districts. Human impacts emanating from the identified pressures could not be evaluated and this task is proposed to be accomplished in further projects. Nonetheless, the resulting information is considered very useful for managers and technical staff to support not only marine management but also other planning and decision making in Spain.
SPATIAL MODELLING OF TANGIBLE AND INTANGIBLE LOSSES IN AN INTEGRATED RISK ANALYSIS
Authors: Burzel Andreas , Dassanayake Dilani R. , Oumeraci Hocine
Published: December 2012

The expected climate change and the associated possible increase of the frequency and magnitude of extreme storm surges may lead to larger storm surge hazards than have been observed in the past. Therefore, the German XtremRisK project aims to improve the understanding of the impact of extreme storm surges under current and future climate conditions by conducting an integrated flood risk analysis for two selected pilot sites in Germany which may be representative for an open coast (Sylt Island) and a megacity in an estuarine area (Hamburg). The research has also been focused on developing and improving the knowledge, methods and models for the assessment of intangible losses (social and environmental), their spatial modelling as well as their integration with direct and indirect economic losses. After a brief introduction into the integrated flood risk analysis being implemented, the paper describes the methodologies and discusses the results with a focus on the modelling of tangible and intangible losses in the pilot site Hamburg-Wilhelmsburg.
COASTAL DUNES VULNERABILITY INDEXES: A NEW PROPOSAL
Authors: Sancho Francisco , Oliveira Filipa S. B. F. , Freire Paula
Published: December 2012

In the present work it is proposed a new coastal dune vulnerability index based on its exposure (and resistance) to overwashing and erosion under storm events, focusing solely on the short-term events. The methodology is applied and validated against the available data for the Ria Formosa (Algarve, Portugal) coastal beaches. The overwash index is determined as a function of the dune crest height in relation with the maxima water levels for different return periods, and the storm-erosion index is computed as function of the remaining beach/dune volume after the impact of
the 10-year return period extreme-wave conditions in relation to the pre-storm volume. It is discussed the results of this application, enhancing the necessity of further validation.
HYDRODYNAMIC IMPACTS OF TIDAL POWER LAGOONS IN THE BAY OF FUNDY
Authors: Cousineau Julien , Nistor Ioan , Cornett Andrew
Published: December 2012

It has long been identified that the Bay of Fundy, Canada, is one of the world's premier locations for the development of tidal power generating systems, since it has some of the world's largest tidal ranges. Several proposals have been made in recent years to find economical ways to harness the power of tides. There is presently considerable interest in installing tidal power lagoons in the Bay of Fundy. The lagoon concept involves temporarily storing seawater behind an impoundment dike and generating power by gradually releasing the impounded seawater through conventional low-head hydroelectric turbines. A tidal lagoon will inherently modify the tides and tidal currents regime in the vicinity of the lagoon, and possibly induce effects that may be felt throughout the entire bay. The nature of these hydrodynamic impacts will likely depend on the size of the tidal lagoon, its location, and its method of operation. Any changes in the tidal hydrodynamics caused by a tidal lagoon may upset ecosystems that are well adapted to existing conditions. The scale and character of the potential hydrodynamic impacts due to tidal lagoons operating in the Bay of Fundy have not been previously investigated. This paper presents the results of a hydrodynamic model developed to analyze, predict, and quantify the potential changes in the tidal hydrodynamics changes (water levels, tidal range, circulation patterns and tidal currents) due to the presence of a single tidal lagoon, or multiple lagoons, operating in the upper Bay of Fundy, Canada. The extent of the changes due to different scenarios involving several number, size and location of lagoons, as well as their operating mode is also investigated. The final purpose of this novel study is to assist with decisions concerning the development of the vast tidal energy resources available in the Bay of Fundy, Canada.
HURRICANE HAZARD ASSESSMENT: CONSIDERATIONS FOR SEA-LEVEL RISE AND CLIMATE CHANGE
Authors: Irish Jennifer L. , Ferreira Celso , Resio Donald T , Olivera Francisco , Hsu Chih Hung
Published: December 2012

Assessment of hurricane flooding risk is an essential component for effective coastal planning and engineering design. Existing methods for evaluating extreme-value flood statistics traditionally assume that flood conditions are stationary, such that historical information represents future conditions. However, dynamic changes in the environment, specifically changing sea levels and potential changes in hurricane intensity and rate of occurrence, mean that future flooding risk will not be adequately represented by historical conditions alone. In this paper, an approach is proposed for incorporating future sea level and hurricane climate projections into extreme-value flood probabilities and risk assessment.
IMPROVING THE NAUTICAL ACCESS TO ZEEBRUGGE HARBOR: A MULTIDISCIPLINARY STUDY
Authors: Martens Chantal , Delgado Rosalia , Verhaeghe Hadewych , Verwaest Toon , Willems Marc
Published: December 2012

A multidisciplinary study was set up by the Maritime Access Division of the Flemish Community to tackle the nautical problems faced by Zeebrugge Harbor. The problem is twofold: strong cross-currents at the harbor mouth hinder the entrance of the ships around high water, and the occurrence of thick muddy layers hinders the navigation in the harbor and causes very high dredging costs. . The article focuses on the global project set up, and explains more in detail the numerical and physical modeling research.
MODELING MICROBIAL WATER QUALITY AT A BEACH IMPACTED BY MULTIPLE NON-POINT SOURCES
Authors: Feng Zhixuan , Reniers Ad , Haus Brian , Solo-Gabriele Helena , Fiorentino Laura , Olascoaga Maria , MacMahan Jamie
Published: December 2012

Monitoring microbial water quality is essential for recreational beaches in order to protect human health. To evaluate the relative importance and impacts of various types of non-point microbial sources at a subtropical beach (Hobie Beach, Miami, USA), we utilized a coastal ocean circulation model (Delft3D) with a microbe transport-fate model. Those non-point sources include beach sediment, dog feces, bather shedding, and rainfall runoff. The hydrodynamic model results agreed well with tidal elevations recorded by a nearby NOAA tidal station and also field data collected by pressure sensors, acoustic Doppler current profiler (ADCP). We modeled enterococci levels from four different types of non-point sources on the beach and Staphylococcus aureus levels from only the bather shedding. Model results suggest that dog feces are spotty sources of enterococci and can result in transient spikes of enterococci levels for hours. Beach sands are pervasive sources of enterococci and may explain observed persistent elevations of enterococci levels at this site. Runoff may also significantly increase enterococci levels during rainfall events while bather shedding contribution of enterococci is almost negligible. Bather is the only Staphylococcus aureus source considered in the study and simulated levels are in the same order as prior field measurements.
GIS-BASED ANALYSIS OF STORM VULNERABILITY CHANGE AT PEA ISLAND, NC
Authors: Hardin Eric , Mitasova Helena , Overton Margery
Published: December 2012

In August 2011, Hurricane Irene opened multiple small breaches along the Outer Banks of North Carolina, USA. To predict storm damage to barrier islands, the United States Geological Survey (USGS) has developed the storm impact scale for barrier islands, which assesses vulnerability based on the configuration of the pre-storm terrain relative to storm characteristics. We present the vulnerability of Pea Island to Hurricane Isabel (2003) and Irene (2011) using an efficient GIS-based implementation of the storm impact scale. This implementation employs a least cost path approach to automated topographic feature extraction and a remote sensing approach to wrack line extraction for storm parameter estimation. The assessed vulnerability along with high-resolution topographic visualizations based on a decadal time-series of Light Detection and Ranging (LiDAR) data suggest that the location of the breach formation was a function of the pre-storm terrain. With the presented methodology, the geospatial information required to identify vulnerable areas can efficiently be extracted so that management strategies can be implemented before storm damage occurs.
AN EARLY WARNING SYSTEM FOR THE ON-LINE PREDICTION OF COASTAL STORM RISK ON THE ITALIAN COASTLINE
Authors: Harley Mitchell D. , Valentini Andrea , Armaroli Clara , Ciavola Paolo , Perini Luisa , Calabrese Lorenzo , Marucci Francesco
Published: December 2012

The ability to predict the imminent arrival of coastal storm risks is a valuable tool for civil protection agencies in order to prepare themselves and, if needs be, execute the appropriate hazard-reduction measures. In this study we present a prototype Early Warning System (EWS) for coastal storm risk on the Emilia-Romagna coastline in Northern Italy. This EWS is run by executing a chain of numerical models (SWAN, ROMS and XBeach) daily, with the final output transformed into a format suitable for decision making by end-users. The storm impact indicator selected for this site is the Safe Corridor Width (SCW), which is a measure of how much dry beach width is available for safe passage by beach users. A three-day time-series of the predicted SCW is generated daily by the prototype EWS. If the minimum SCW exceeds a certain threshold, a warning is issued to end-users via an automated email service. All available prediction information is also updated daily on-line. Over the one year that the EWS has been operating (June 2011 until June 2012), 13 "code red† and 16 "code orange† warnings have been issued, with the remaining 305 predictions indicating low hazard in terms of the SCW. The reliability of the predictions from the perspective of the end-user has meant that the EWS is currently being expanded to include the entire Emilia-Romagna coastline.
ANALYSIS OF THE CARBON FOOTPRINT OF COASTAL PROTECTION SYSTEMS
Authors: Labrujere Astrid Louise , Verhagen Henk Jan
Published: December 2012

When calculating the Carbon Footprint for a product or service, a direct link is made between the total amount of consumed energy and the produced amount of carbon dioxide during production. For that reason calculating the carbon footprint of various alternatives is a very straightforward method to compare energy consumption and more importantly environmental pollution. Applying this method to large hydraulic engineering projects is not being done frequently. In this study the possibilities to apply the Carbon Footprint method to coastal protection systems have been explored and analyzed. The analyses are based on a case study: A reinforcement work at the Dutch coast.
WAVE RUNUP PREDICTION FOR FLOOD MAPPING
Authors: Melby Jeffrey , Caraballo-Nadal Norberto , Kobayashi Nobuhisa
Published: December 2012

Wave runup determines the extent over which waves act. Wave runup is therefore an important parameter to determine flood inundation extents from coastal storms. Cross-shore and longshore sediment transport are a function of the hydrodynamics on the beach and are therefore related to wave runup. Several benchmark wave runup data sets are summarized and used to evaluate the available tools for predicting wave runup for flood hazard assessment. Benchmark data span a range of shoreline conditions including sandy beaches on the Pacific and Atlantic coasts, dissipative to reflective beaches, as well as structures ranging from impermeable smooth levees to rough permeable rubble mounds. Data include laboratory and prototype measurements. Tools for predicting wave runup are analyzed including empirical equations, computer programs based on empirical equations, and the CSHORE time-averaged cross-shore model. Most of the tools show fairly high degrees of skill but some do not. The study recommends using CSHORE to model runup for most beach and structure conditions. However, CSHORE is not likely to predict wave runup on infragravity-dominated dissipative beaches well. For these cases, it is recommended that one of the recommended empirical equations for beaches be used.
HAWAII HURRICANE WAVE AND SURGE MODELING AND FAST FORECASTING
Authors: Smith Jane McKee , Kennedy Andrew B. , Westerink Joannes J. , Taflanidis Alexandros A. , Cheung Kwok Fai
Published: December 2012

The US Army Corps of Engineers' Surge and Wave Island Modeling Studies developed a fast forecasting system for hurricane waves and inundation in Hawaii. The system is based on coupled high-resolution, high-fidelity simulations of waves and surge applying the SWAN and ADCIRC numerical models on a 2D finite-element grid. Additionally, wave runup is simulated on high-resolution cross-shore transects using the Boussinesq-equation model BOUSS-1D. Approximately 1500 storms were simulated to cover the range of hurricane parameters of landfall location, track angle at landfall, central pressure, forward speed, and radius of maximum winds expected to impact Hawaii. To create a forecast system that is fast and robust, a moving least-squares response surface surrogate model was developed based on the high-fidelity model results. The surrogate model is approximately seven orders of magnitude faster than the high-fidelity simulations. The efficiency of the surrogate model allows both deterministic and probabilistic simulations in seconds to minutes on a personal computer.
COASTAL FLOOD RISK: THE IMPORTANCE OF INTANGIBLE LOSSES AND THEIR INTEGRATION
Authors: Dassanayake Dilani Rasanjalee , Burzel Andreas , Oumeraci Hocine
Published: December 2012

The joint research project "XtremRisK† was initiated with the main objective of enhancing the knowledge with respect to the uncertainties of extreme storm surge predictions as well as quantifying exemplarily the flood risk under current conditions and future climate scenarios exemplarily for two pilot sites in Germany: Sylt Island representative for an open coast and Hamburg for an estuarine urban area. Flood risk is generally determined by the product of the flooding probability and the possible losses associated with the flood event. Flood losses are categorized as tangible and intangible depending on whether or not the losses can be assessed in monetary values. Up to date, intangible loses are not or only partially incorporated in flood risk analysis due to the lack of appropriate evaluation and integration methodologies. This study focuses on developing methodologies for the evaluation of intangible losses due to flooding and for their integration with tangible losses in flood risk analysis
FIELD OBSERVATIONS OF SHORELINE CHANGE BY FREQUENCY-BANDED WAVE ENERGY FLUX AND FORESHORE SHAPE
Authors: Suzuki Takayuki , Kuriyama Yoshiaki
Published: December 2012

In this paper, correlations between shoreline change rates and six frequency-sectioned wave energy fluxes were discussed using a 5-year data set of beach profiles and offshore waves observed at the Hasaki coast. Also, an effect of foreshore beach shape on shoreline backward movement speed was discussed. From the results, it is possible to separate shoreline erosion events from shoreline advance events and shoreline stand still events by using frequency-sectioned wave energy fluxes. Furthermore, the results revealed that the shoreline position and foreshore shape affect shoreline backward movement speed. This indicates that for the estimation of the shoreline change rate, we need to consider not only wave energy but also shoreline position and foreshore shape.
THREE†DIMENSIONAL STRUCTURE OF WIND†DRIVEN CURRENTS ACCOMPANIED WITH SECONDARY CIRCULATIONS AND THEIR EFFECTS ON THE THERMAL STRUCTURE OF LAKES AND OCEANS
Authors: Uzaki Ken-ichi , Ide Koji , Araki Yosuke , Horiguchi Shinya
Published: December 2012

Wind-driven currents "WDC" play an important role on the material transport in lakes and oceans. Generaly, the horizontal profile of WDC is forecasted uniformly almost with 3% of U10 to the surface speed. However, Secondary circulations named "Langmuir Circulations : LCs†, which have axes in the wind direction, are often formed in WDC. When LCs are formed, it is suggested that the horizontal profile of WDC becomes the spatially periodic one which has the high-speed area and the low-speed area alternately. In the high-speed area, the surface speed is suggested much larger than 3% of U10. It is very important to estimate precisely the surface speed in the high-speed area in order to forecast accurately the material transport due to WDC. Furthermore, the vertical mixing by LCs is suggested to have an significant effect on the thermal structure in lakes and oceans because the maximum vertical speed of LCs is estimated about 1/3 of surface speed. In this study, the horizontal profile of WDC are observed by H-ADCP and the vertical profile of thermal structure are also observed by the thermistor chain in order to estimate the effects of LCs on them.
WAVE HEIGHTS RECOVERY FROM SUBSURFACE PRESSURES UPON A SMALL VERTICAL CYLINDER
Authors: Mai Tri Cao , Schlurmann Torsten
Published: December 2012

In this paper, the fluctuation of water surface has been recovered from subsurface dynamic pressures exerted on a small vertical cylinder of a tripod structure and it finds that the wave heights can be estimated accurately from the pressures measured at Î¸ = 180°. Seven pressure transducers were mounted around the cylinder to get the circumference distribution of the dynamic pressures. The time histories of the water surface fluctuations and the concurrent dynamic pressures upon the cylinder have been analyzed in frequency domain. A part of the linear diffraction theory of MacCamy & Fuchs has been applied to analyze the experimental data. Additionally, the empirical factor, which is the ratio of the measured and recovered wave height, is presented.
EVALUATION OF SEAGRASS AS A WAVE ENERGY DISSIPATION ELEMENT
Authors: Mendoza Edgar , Hoil Jose , Silva Rodolfo , Enriquez Cecilia
Published: December 2012

In shallow water, particularly near the coast, the hydrodynamics are influenced by bottom friction which, increases with depth reduction and the complexity of the sea floor, mostly in the presence of vegetation. Although little is still known about the seagrass capability to reduce wave energy, it is known to increase the sediment stability in anthropogenically disturbed areas; hence the interest of evaluating their efficiency as a means for coastal protection.
WAVE TRANSFORMATION PATTERNS AT A NON-TIDAL, DISSIPATIVE BEACH
Authors: Valsamidis Antonios , RóÅ¼yÅ,,ski Grzegorz , Reeve Dominic
Published: December 2012

In this study, the statistical method of the Canonical Correlation Analysis (CCA) was applied in order to gain insight into the interaction of nearshore wave climate and the morphological evolution of the seabed at Lubiatowo beach in Poland. Lubiatowo, a non-tidal, sandy beach characterized by multiple longshore bars (Figure 1) is typical of Southern Baltic coasts. In the past, this method has also been used in the coastal field by Larson et al. (2000). Rozinsky (2003) also used the CCA to find a correlation between components of a multibar system and the interaction between the multiple longshore bars. Elsewhere, Horrillo-Caraballo and Reeve (2008), examined the performance of CCA-based at Duck (USA).
POT METHODS: A NEW INSIGHT INTO THE ESTIMATION OF EXTREME VALUE DISTRIBUTIONS - APPLICATION TO EXTREME WAVE HEIGHTS
Authors: Mazas Franck , Hamm Luc , Garat Philippe
Published: December 2012

Within the framework of the GPD-Poisson model for determining extreme values of environmental variables, we examine the sensitivity of this methodology to the lowest and to the largest data of the sample. We show the need for a clear distinction between the threshold selecting the data to be fitted with a location parameter setting the origin of the distribution and that the introduction of this latter parameter yields stable results, consistent with the physics. We also show that the likelihood maximum of the classical model is reached at an open upper bound of the parameter space with non-null derivatives: hence, the asymptotic properties of MLE are not proven and one should be quite cautious when using it. Applications are presented with real and simulated data.
APPLICATION OF A SEMI-EMPIRICAL LONGSHORE TRANSPORT FORMULATION
Authors: Barbaro Giuseppe , Tomasicchio Giuseppe Roberto , Malara Giovanni , D'Alessandro Felice
Published: December 2012

The present paper deals with the determination of longshore sediment transport rate. Specifically, case study of Saline Joniche (Reggio Calabria, Italy, is discussed. This case is of interest because, in this location, an artificial basin was built in the 70's. After few years, port entrance experienced total obstruction by sand. Actually, the area is abandoned and several projects have been proposed for revitalising port activities.

This paper discusses a method for estimating the longshore sediment transport rate at Saline Joniche and complements previous methodology.
CHARACTERISTICS OF OXYGEN CONSUMPTION BY SEDIMENT UNDER HYPOXIC CONDITION IN ENCLOSED COASTAL SEAS
Authors: Endo Toru , Shigematsu Takaaki , Mizuta Keisuke
Published: December 2012

Enclosed coastal seas are suffering from serious environmental problems which caused by hypoxic condition occurring at the bottom of sea during summer season. Although many restoration technologies for supplying oxygen to the bottom of the sea are developed, it is necessary to understand the characteristics of sediment oxygen consumption (SOC) before applying these technologies in actual field because it is thought that the sediment oxygen demand increases under hypoxic condition. In this study, we carried out the field investigations for a year at Osaka bay by using a new chamber method which can measure SOC under hypoxic condition in order to examine the seasonal variations of SOC. In addition we conducted the laboratory experiment for examining the effects of biological and chemical factor on the SOC.
NUMERICAL ANALYSIS OF TSUNAMI PROPAGATION ON WIDE REEF PLATFORM
Authors: Mikami Takahito , Shibayama Tomoya
Published: December 2012

During the 2009 Samoan Islands Tsunami, the wide coral reef platform in front of the islands affected the approaching tsunami behavior. This research aims to understand the characteristics of a tsunami propagating over a reef platform by using a turbulence model. A Large Eddy Simulation (LES) model was used to simulate wave breaking and energy dissipation. The results of numerical simulations by using LES model were shown to reproduce well the results of the field survey in the 2009 Samoan Islands Tsunami. The present method may also apply to other countries which have coral reefs and contribute to regional tsunami mitigation strategies. It is important to understand what is the phenomenon that people in coastal areas actually experience as well as the height and arrival time of a tsunami.
OVERTOPPING CHARACTERIZATION FOR THE ELABORATION OF VULNERABILITY MAPS IN PORTS FACILITIES
Authors: Campos Alvaro , Llana Alberto , Molina Rafael , Alises Ana , Gomez Rebeca , Castillo Carmen
Published: December 2012

Overtopping has been widely studied (European project CLASH 2000-2010), and mean and maximum overtopping discharge values have already been proposed. However, fundamental variables for determining overtopping affections and risks, such as the shape and energy of the overtopped water mass and how it is distributed in the possible affected zones (vulnerable areas), are not yet defined.

This study focuses on getting deeper comprehension of the flow-structure interaction. Different overtopping types have been characterized and a first step in the extension of the parametric map proposed by Mc Conel (1998) by including an overtopping term has been done. Also, a new mean overtopping rate (qnew) has been proposed, taking into account just the total overtopping time instead of the total test's duration (q). This new way of measuring the mean overtopping rate seems to permit a more realistic characterization of overtopping as it gives a clue of the individual volumes of each overtopping event, which is fundamental for a risk evaluation.
LONG TERM MORPHOLOGICAL EVOLUTION OF THE GOLD COAST SEAWAY: HISTORICAL AND NUMERICAL ANALYSIS
Authors: Sedigh Mahnaz , Tomlinson Rodger , Golshani Aliasghar , Cartwright Nick
Published: December 2012

The Gold Coast Seaway is one of two main tidal inlets located on the Australian East coast at a longitude of 27°56'10S and a latitude of 153°25'60E linking an intra-coastal waterway known as The Broadwater with the Pacific Ocean.. The reasons for construction of the Gold Coast Seaway and the associated sand by-passing system in the 1980s were stabilising the entrance, maintaining a safe navigable channel, preventing shoreline erosion to the north and maintaining an adequate beach width to the south.
VULNERABILITY OF COASTAL STRUCTURES WITH FUSE ELEMENTS
Authors: Abanades Javier , Campos Alvaro , Castillo Carmen
Published: December 2012

Vulnerability of coastal structures is very important especially in low-lying areas considering sea level rise and the increase in severity of other associated agents. The vulnerability of a vertical breakwater is defined as the probability of attaining a level of damage under different classes of external actions. The damage can be related to reliability or operationality and the external action is defined with a global descriptor, usually, it will be the maximum significant wave height in a storm. As expected, the comparison between actual and optimized breakwater shows an increase of the probability of collapse (level 3) for Hs > 4m, although these waves have a small probability of occurrence. The latter section was designed using probabilistic techniques. On one hand, the comparison between sections with and without fuse element shows an increase on the probability of damage level 2 in the former because this level includes the simultaneous occurrence of fuse failure and, therefore, an increase in overtopping which exceeds the tolerance. On the other hand, the fuse element reduces the probability of level 3 (collapse: caisson failure) for Hs between 4 and 6m for the optimized section. The fuse element is shown to be more efficient when there are no activities on the lee of the breakwater.