bluuebunny/crossref_metadata_2025 huggingface dataset:
INVESTIGATION OF WAVE INDUCED STORM SURGE WITHIN A LARGE COASTAL EMBAYMENT - MORETON BAY (AUSTRALIA)
Authors: Treloar Philip , Taylor David , Prenzler Paul
Published: October 2012

Moreton Bay is a large coastal embayment on the south-east Queensland coast which is surrounded by the urbanised areas of greater Brisbane on its western and southern shorelines. It is protected from the open coast by a number of islands, including South Stradbroke, North Stradbroke and Moreton Islands. Tropical cyclones occasionally track far enough south to cause significant damage to south-east Queensland due to flooding, winds, waves and elevated ocean water levels. Distant tropical cyclones which may be several hundred kilometres north of Moreton Bay have been known to cause storm surge, high waves and erosion inside Moreton Bay. These events generally do not generate gale force winds within Moreton Bay, but can generate large ocean swell waves. It has been identified that the wave conditions generated from distant cyclones can cause a variation in water levels inside Moreton Bay. A detailed study was undertaken to investigate the regional wave set-up process which affects Moreton Bay. The simulation of the residual water levels within Moreton Bay using a coupled hydrodynamic and wave model system developed for this study is considerably more accurate than applying a hydrodynamic model alone and explains water level anomalies that have a tidal frequency. The paper discusses the physical process of regional wave set-up inside a large embayment, analysis of observed residual water level and also the modelling study undertaken to quantify the influence of waves on storm tide levels inside Moreton Bay. The storm tide hazard study for the Moreton Bay Councils included the effects of regional wave set-up in the specification of design water levels.
AN ADVANCED STATISTICAL EXTREME VALUE MODEL FOR EVALUATING STORM SURGE HEIGHTS CONSIDERING SYSTEMATIC RECORDS AND SEA LEVEL RISE SCENARIO
Authors: Mudersbach Christoph , Jensen Juergen
Published: October 2012

In this paper, a non-stationary extreme value analysis approach is introduced in order to determine coastal design water levels for future time horizons. The non-stationary statistical approach is based on the Generalized Extreme Value (GEV) distribution and a L-Moment parameter estimation as well as a Maximum-Likelihood-estimation. An additional approach considers sea level rise scenarios in the non-stationary extreme value analysis. All the methods are applied to the annual maximum water levels from 1849-2007 at the German North Sea gauge at Cuxhaven. The results show, that the non-stationary GEV approach is suitable for determining coastal design water levels.
EXTREME SCENARIOS AT THE GERMAN NORTH SEA COAST A NUMERICAL MODEL STUDY
Authors: Bruss Gerd , Gönnert Babriele , Mayerle Roberto
Published: October 2012

A procedure, based on numerical models is proposed to investigate the processes involved during conditions of extreme water levels within the outer Elbe estuary at the German North Sea coast. Nonlinear interactions between the different processes are analyzed and adverse combinations are simulated yielding new scenarios. Various conditions in the astronomical tide, three major storm events over the North Sea, several external surges and an increase in the mean sea level are analyzed. Techniques for the modeling of each of the isolated processes are developed and individually verified. The isolated processes are temporally shifted relative to each other and superimposed in various combinations. The results obtained from the present method, provide new insights into the nonlinear interactions between the involved processes. Generally, the effects of the processes seem to be reduced in superpositions with high absolute water levels. However, due to the large scatter of the results no general relations are found. New extreme scenarios are determined by iterative maximizations of the peak water level of different superpositions around spring high tide.
THE NUMERICAL MODELLING OF THE EFFECT OF OCCURRENCE DURATION ON THE WATER LEVEL DIFFERENCE FOR THE BOSPHORUS STRAIT
Authors: Ozturk Mehmet Nuri , Yuksel Yalçın
Published: October 2012

The straits connecting two large water bodies show highly strong and stratified currents related to meteorological, morphological and hydrodynamic conditions. The Bosphorus is a long sea strait connecting the Black Sea and the Sea of Marmara. There is a two layer current system in the Bosphorus, which is largely determined by conditions at the Black Sea. The upper layer flows from the Black Sea to the Sea of Marmara caused by decline in surface elevation between the Black Sea and Sea of Marmara. The lower layer flows in opposite direction caused by the density difference which is due to the difference in salinities.
In this study the effect of occurrence duration of water level difference (Î"h) on the Bosphorus current structure was modelled using a three dimensional hydrodynamic modelling approach. The approach is based on an unstructured flexible mesh and uses a finite volume solution technique, which provides an optimal flexibility while retaining an efficient numerical solution. The meshes are based on linear triangular elements. An uniform rectangular channel which has simple geometry compare with Bosphorus was used for modelling. The channel has Bosphorus average values in dimensions. It is 900 m in width, 32,000 m in length and 64 m in depth. The constant salinty bondary conditions were described at the open bondaries corresponding Marmara and Black Sea boundaries and no water level difference as initial surface elevation. Using k-Îµ turbulence choice and hydrostatic pressure assumption, the two different occurrence duration for the same increase at the water level difference were modelled. In the first case the increasing of the duration for the water level difference described shorter than the second case. The model results show that, in the first case one-layered flow becomes dominated whole the channel flow, on the other hand in the second case two-layered flow persisted.
REAL-TIME TSUNAMI INUNDATION PREDICTION USING OFFSHORE TSUNAMI OBSERVATION
Authors: Tatsumi Daisuke , Tomita Takashi
Published: October 2012

The previous real-time tsunami prediction based on the inversion method and the linear superposition can predict the tsunami in near shore area quickly, but it can not predict the tsunami inundation. The present study developed the empirical formula to estimate the overflow rate from the tsunami profile predicted by the previous method. Moreover, the level fill method was applied to predict the tsunami inundation from the estimated overflow rate. Numerical experiments using the actual topography and the historical earthquakes proved that the combination of the previous method, the empirical formula to estimate the overflow rate, and the level fill method can predict the tsunami inundation quickly from the offshore tsunami observation.
AN OPEN BOUNDARY CONDITION FOR APPLICATION IN NUMERICAL COASTAL MODELS
Authors: Ma Peifeng , Madsen Ole Secher
Published: October 2012

Open boundaries (OBs) are usually unavoidable in numerical coastal circulation simulations. At OBs, appropriate open boundary conditions (OBCs) are required and a good OBC should be able to let outgoing waves freely pass to the exterior of a computational domain without creating reflections at the OBs. In the present study, a methodology has been developed to predict two parameters, phase speed c_r and decay time T_f, in a standard OBC formulation, so that the OBC is significantly improved compared to commonly used existing OBCs with specified c_r and T_f. For the conditions where wave period is unknown, the OBC with approximated c_r and T_f may be applied and a test reveals that this OBC is able to yield good results in typical coastal flow conditions. In addition, a Swing-Door Boundary Condition (SDBC) is proposed and tested for application at an offshore open boundary where both incoming and outgoing waves exist.
INFLUENCE OF TIDAL INLET DEPTH ON WATER LEVEL RESPONSE AND SALINITY INTRUSION IN A LAGOON
Authors: Watanabe Kazuya , Tanaka Hitoshi
Published: October 2012

The Nagatsura-ura Lagoon in Miyagi Prefecture, Japan is a semi-enclosed water area that has been used for aquaculture of oyster for these forty years. Recently, however, death of oysters has frequently occurred due to anoxic water near the bottom, and is a big concern among stakeholders. The Nagatsura-ura Lagoon and Oppa Bay are connected by shallow tidal inlet, and its water depth greatly affects hydrodynamics and water environment in the lagoon. In this study, time variation of water level in the lagoon in response to tidal variation is investigated through spectral analysis to quantify the role of water depth in the hydrodynamic process. Furthermore, the relationship between the inlet water depth and the salinity concentration intruding into the lagoon is examined through 3-D numerical simulation.
COMPARISON OF TIDAL CURRENTS UNDER DIFFERENT NOURISHMENT SCHEMES ON WEST BEACH OF BEIDAIHE, CHINA
Authors: Zhang Yu , Kuang Cuiping , He Lulu , Pan Yi , Yang Yanxiong , Zhang Jiabo , Liu Shuguang
Published: October 2012

This paper detailed a study on the tidal current field around a beach nourishment project including submerged breakwaters and jetties. The effect of different nearshore structure arrangements on the tidal current field was studied utilizing a numerical model build based on the solution of two-dimensional shallow water equations and an unstructured grid. In order to calibrate the numerical model, field survey was conducted at 5 current stations and a tidal level station around the project area. According to a primary analysis on stability, environment, sight of the beach, and construction quantity, four project schemes were chosen and simulated. After comparing the modeling results, the effects of submerged breakwaters and jetties were discussed. Conclusively, it is feasible to protect the filled sand on west beach by jetties and submerged breakwaters through obvious tidal current velocity reduction in the nearshore area.
QUANTIFICATION OF TIDAL WATERTABLE OVERHEIGHT DUE TO THE SLOPING BEACH IN UNCONFINED AQUIFERS
Authors: Song Zhiyao , Zhang Zhuo , Li Ling
Published: October 2012

Based on a liberalized one-dimensional Boussinesq model and the previous study results, this paper provides two experience solutions to quantify the tidal groundwater overheight behind arbitrary sloping beaches. One solution is obtained with an asymptotic matching method advanced by Guo, and the other solution is origined by the analytical solution as perturbation parameter less than unity, the errors of both solutions compared with numerical solution are small and acceptive for the application.
STEADY CURRENTS INDUCED BY SEA WAVES PROPAGATING OVER A SLOPING BOTTOM
Authors: Capodicasa Erminia , Scandura Pietro , Enrico Foti
Published: October 2012

A numerical model aimed at computing the mean velocity generated by a sea wave propagating over a sloping bottom, offshore the breaker line, is presented. The model is based on the assumption that the fluid domain can be partitioned into two boundary layers and a core region where at a first order of approximation the flow can be regarded as irrotational. The irrotational flow is computed by using a theory based on the assumption of small amplitude waves which allows both fully absorbed waves and partially reflected waves at the coastline to be considered. The distribution of the mean velocity is controlled by the ratio between the thickness of the boundary layer and the wave amplitude. When this ratio is small, the mean velocities are rather constant along the depth and a second boundary layer develops close to the bottom. In the case of fully reflected waves such boundary layer separates and the mean vorticity can be convected far from the bottom.
FIELD OBSERVATIONS OF SEICHE EVENTS IN A T-SHAPE BAY
Authors: Asano Toshiyuki , Yamashiro Toru , Kakinuma Taro
Published: October 2012

Field observations on secondary oscillations (seiche) in Urauchi Bay of Kami-koshiki Island, Japan were conducted during October 7-21, 2008. The seiches prone bay has a unique configuration as T-shape, which may cause the inherent characteristics of the eigen oscillations. The analyzed data show that the oscillations of the bay have at least two distinct modes; mode-1 oscillation of the period around 25 minutes with forming anti-nodes at the both inward inlets and possessing a node at the bay mouth, mode-2 oscillation of the period around 12 minutes which oscillates between the both inward inlets having the node at the branching point. Next, numerical simulations were conducted to reproduce the secondary oscillations in the bay by providing input sinusoidal waves with the eigen periods of oscillations to the calculating bay geometry. The numerical results are found to show basically consistent characteristics with the field observations.
TSUNAMI EARLY DETECTION:ENHANCED RESOLUTION OF HF OCEANOGRAPHIC RADAR
Authors: Murata Yasuhiro , Nagakura Toshiro , Kokai Takahiro
Published: October 2012

HF Oceanographic radar is an equipment, for instantaneously sensing velocity distribution of sea surface current. It has a
wide field of view, which extends approximately ±45° in direction and beyond 50km in distance. There are high
expectations that the radar observation of Tsunami will become a new road path for preventing disasters. In this paper, we
describe a method to enhance the resolutions of radar in both time and current. At first, resolutions required for tsunami
observation are estimated by simulating a Tokachi-oki earthquake tsunami (2003). Here it is pointed out that traditional
data processing indicates inadequate resolutions for tsunami early detection. Secondly, two techniques are proposed to
achieve the necessary resolutions. Short-time Fourier transform (STFT), in place of normal FFT, enhances the time
resolution of Doppler analysis. Further, zero-padding technique improves the current resolution, by interpolation of data
within the frequency domain. Finally, by means of simulation, it is verified that these proposed techniques give improved
resolutions in both time and current.
ON BASIC CONDITIONS FOR LONG-WAVE SIMULATIONS IN HARBORS BY THE BOUSSINESQ MODEL
Authors: Ota Kazuyuki , Yoshida Akinori , Yamashiro Masaru , Nishii Yasuhiro
Published: October 2012

For wave field calculations to estimate long-period ship motions in harbors, the so-called Boussinesq model seems to be widely used because of its versatility. However, it has not yet been clarified how large the sponge layer should be to simulate an open-sea condition, how long the computation should be continued to obtain a statistically stable spectrum, and what size of computational area should be considered. In this study, these basic conditions were investigated by conducting wave field simulations using the Boussinesq model. Useful information was obtained such as: (1) the thickness of the sponge layer can be much less than the thickness expected from one-dimensional calculations, (2) the data length to obtain a stable spectrum needs to be much longer than statistically expected 3 to 5 hours, and this is because the beat waves are produced by selectively amplified component waves near resonant frequencies in harbors.(3) the size of the computational area does not affect the results greatly and the distance 3 km between the end of the breakwater and the lateral sponge boundary is practically sufficient for the harbor mouth opening.
OSCILLATIONS OF SEMI-ENCLOSED WATER BODY INDUCED BY HURRICANES
Authors: Tan Paul Yuan-Hung , Lee Jiin-Jen
Published: October 2012

The primary focus of this research is to study the oscillations of semi-enclosed water body induced by hurricanes. The physical mechanisms of the wind-induced oscillation (storm surge) in a semi-enclosed water body are analyzed by the depth-averaged, non-linear shallow-water equations. The numerical model using the finite-volume method (FVM) to solve the depth-averaged, non-linear shallow-water equations is developed and the present model is verified by the intensive field data reported by IPET. The present model is further applied to the investigation of the oscillations (storm surges) in Lake Pontchartrain induced by the winds generated by four synthetic hurricanes within the time-span of 00:00 UTC August 29 to 00:00 UTC August 30, 2005: 1.Hurricane Katrina tracking on its original route, 2.Hurricane Katrina tracking 36 km west of its original route, 3.Hurricane Katrina tracking 72 km west of its original route, and 4.Hurricane Katrina tracking on its original route with reduced forward speeds. The major application of the present model is to assist the design of the water-front structure surrounding the semi-enclosed water body that has been influenced by the oscillations induced by hurricanes. The numerical simulations generated by the present model can help the planners to determine a better strategy of the hurricane protection systems surrounding the communities of the semi-enclosed water body.
HARBOR RESONANCE: A COMPARISON OF FIELD MEASUREMENTS TO NUMERICAL RESULTS
Authors: Xing Xiuying , Lee Jiin-Jen , Raichlen Fredric
Published: October 2012

Wave induced oscillation at Bay of Fundy has been studied using a numerical model. From the response characteristics obtained it is seen that the fundamental mode of oscillation at the Bay of Fundy region coincides with the tidal period. The resonant mode of oscillation at the tidal period (12.42 hr) helps explain why Bay of Fundy has the largest tidal range in the world. The numerical results compared well with the tidal records at thirteen tide gauge stations in Bay of Fundy. Discussion also includes numerical results and field measurements at Crescent City harbor and at Los Angeles/Long Beach harbor to show the relationship of the characteristic length of the harbor basin with the resonant periods computed and measured. It is found that the resonant phenomena at these three harbors occurred on normal days although they are very different in size.
FLUCTUATION OF RIP CURRENT MEASURED IN SHALLOW WATER REGION WITH SMALL TIDAL RANGE
Authors: Deguchi Ichiro , Arita Mamoru , Yoshii Takumi
Published: October 2012

Disappearance and formation processes of rip channel are discussed based on the field measurements of wave height, current velocity, bottom topography and flow pattern of near-shore current. Sudden increase in wave height together with the change in the wave direction took place during a half day caused these phenomena and rip current rose and fell according to the transition of the bottom topography. Furthermore, flow pattern of rip current was not steady but transformed itself with low frequency fluctuations of the period of few minutes. It is found that such low frequency fluctuations are caused by the intrinsic fluctuations of the incident waves (grouping waves) through the numerical simulations.
ON THE BOTTOM SHEAR STRESS DURING LONG WAVE RUNUP AND BACKWASH
Authors: Shimozono Takenori , Okayasu Akio , Mishima Teppei
Published: October 2012

Laboratory experiments were performed to examine flow characteristics during runup and backwash of a breaking solitary wave. Boundary layer flows were measured by LDV at two locations landward of the still shoreline under different bed conditions. Temporal variations of the bottom shear stress were estimated from nearbed velocity profiles with different methods. The shear stress determined through the logarithmic fitting roughly agreed with that deduced from a depth-integrated momentum balance during turbulent flow phases. The friction factors during the active phases of the runup and backwash were similar in magnitude except in the leading tip where the value sharply increased. A movable bed experiment was also carried out under the same geometry to discuss relations between the bottom shear stress and sediment transport. The result indicated clear dependencies of bed deformations on the magnitude and duration of the exerted shear stress.
NUMERICAL COMPUTATION OF INFRAGRAVITY WAVE DYNAMICS AND VELOCITY PROFILES USING A FULLY NONLINEAR BOUSSINESQ MODEL
Authors: Cienfuegos Rodrigo , Duarte L. , Suarez L. , Catalán P. A.
Published: October 2012

We present experimental and numerical analysis of nonlinear processes responsible for generating infragravity waves
in the nearshore. We provide new experimental data on random wave propagation and associated velocity profiles in
the shoaling and surf zones of a very mild slope beach. We analyze low frequency wave generation mechanisms and
dynamics along the beach and examine in detail the ability of the fully nonlinear Boussinesq- type model SERR1D
(Cienfuegos et al., 2010) to reproduce the complex dynamics of high frequency wave propagation and energy transfer
mechanisms that enhance infragravity wave generation in the laboratory.
MEASUREMENTS OF THE STEADY CURRENTS OUTSIDE THE SURF ZONE
Authors: Scandura Pietro , Capodicasa Erminia , Foti Enrico
Published: October 2012

The results of an experimental study concerning with the measurements of the steady current induced by sea waves approaching the coast are reported. The experiments have been performed in a large wave flume in order to minimize the scale effects. The measurements have been carried out at four different stations along the wave flume by using Acoustic Doppler Velocimeters. The results show that the mean velocity profiles are significantly influenced by the wave period. In particular, when the period reduces the mean velocity gradient close to the wave trough increases. The trend of the velocity profiles is different from that predicted by the theory and mostly reported by other experiments. However, experimental results are reported in literature which are in a qualitative agreement with the present ones.
A NEW 3D ROLLER APPROACH FOR FACING ROTATIONAL SURF ZONE HYDRODYNAMICS
Authors: Viviano Antonino , Musumeci Rosaria Ester , Foti Enrico
Published: October 2012

A 2DH highly nonlinear Boussinesq-type of model for breaking waves has been developed in order to investigate surf zone hydrodynamics, also in the presence of complex bathymetries. The set of equations includes continuity and rotational momentum equations, coupled with the vorticity transport equation. An appropriate spatial definition of the 3D roller concept, along with an algorithm for accurately tracking the roller position, have been on purposely developed. Several numerical simulations have been carried out for the case of a submerged elliptic shoal. The results have been compared with both experimental data and with the results of other numerical models available in the literature. Finally, the vorticity dynamics under a breaking wave has been analyzed both in time and space, showing that a fairly correct interpretation of the wake effect in the rear part of the wave crest is obtained.
NUMERICAL MODELING OF OPTICAL PROPERTIES INSIDE THE SURFZONE
Authors: Shi Fengyan , Ma Gangfeng , Kirby James T.
Published: October 2012

This paper provides a review of our recent developments in numerical models for predicting physical processes related to optical properties inside the surfzone. Model components in the developments include the bubble entrainment model, 2D and 3D multiphase two-fluid models for modeling quiescent phase of bubbles, turbulence models with influences of bubbles, bubble coalescence and breakup models used in the two-fluid models, and foam model for predicting foam patch generation and evolution inside the surfzone. The paper summarizes theories used in the model components and shows some numerical results from model tests.
LABORATORY OBSERVATIONS OF IMPACTS ON COARSE SEDIMENT BEACHES
Authors: Ball Ian , Mendoza-Baldwin Edgar , Simmonds David , Pedrozo-Acuña Adrián , Reeve Dominic E
Published: October 2012

In this paper we present laboratory observations of plunging wave breaker impact pressure responses on a steep coarse-grained beach, extending previous work conducted by Pedrozo-Acuña et al. (2008). Scale laboratory measurements of plunging breaker impact events are reported and compared with the previous full-scale tests. These tests extend the previous relationships to a wider range of surf-similarity parameters and indicate a continued reduction in impact pressure as the transition from plunging impacts to surging impacts is approached. Additional results from scale tests conducted on a smooth impermeable slope also indicate the presence of a maximum impact pressure within the plunging breaker region; however also suggest it may be necessary to include roughness and permeability in the parameterization of the impact pressure.
SEEPAGE FLOW IN A BREAKER ZONE
Authors: Kakinuma Taro , Ohishi Shizuka , Nakamura Kazuo
Published: October 2012

Seepage velocities in several breaker zones were measured with dye for visualization. Pressure gauges were also installed to obtain pore water pressure. Three cases of different incident-wave periods were treated in laboratory experiments. The time-averaged pore water pressure was higher near the shoreline, resulting in the seepage flow, the maximum velocity of which was larger as the incident-wave period was longer, generally moving from onshore to offshore. The penetrated water flowed out from the permeable seabed at a bar top or on the rather offshore side of the bar top if a bar was developed remarkably. The pore water pressure in the breaker zone showed time variation depending on the wave phases including wave breaking and bore propagation. There was a phase when the pore water pressure was locally low below the bar.
TSUNAMI RESONANCE IN THE PALMA DE MAJORCA BAY AND HARBOUR INDUCED BY THE 2003 BOUMERDES-ZEMMOURI ALGERIAN EARTHQUAKE (WESTERN MEDITERRANEAN)
Authors: Vela Jordi , Pérez Begoña , González Mauricio , Otero Luis , Olabarrieta Maitane , Canals Miquel , Casamor Jose Luis
Published: October 2012

During the tsunami of May 2003 in the Balearic Islands, generated by the Algerian earthquake, most of the damage and economic losses occurred inside the harbours, due to high frequency oscillations of relatively large amplitude, combined effect of the tsunami and local resonances. It can be said in fact that this was the more important effect at the islands, where no important inundations is known to have occurred outside the harbours, showing up that even tsunamis with low amplitudes can cause serious damages due to resonance effects. Several tide gauges recorded the seismic-generated tsunami, so comparison of simulations and observations became possible, and made this event a very interesting case for modeling experiments. The main objectives of this work is to understand how was the energy transformation of the tsunami from the source area to the Palma de Mallorca bay and harbour, and to verify if a resonance phenomenon was induced in the harbour.
THE ADVANCE ON CHINA COASTAL ENGINEERING
Authors: Xie Shileng , Zuo Qihua , Dou Xiping
Published: October 2012

An overall introduction is made in this paper to the progress of coastal engineering in the mainland of China during the last two decades, covering the regulation engineering and training effects of the deep navigation channel of the Yangtze River estuary and the Pearl River estuary; the coast protection standards, beach protection and reclamation engineering as well as various types of structures; ports construction and development; the key technology achievements in hydrodynamics of the silty and sand coasts and radial sandbanks; and the main technological development of several large-size cross-sea bridges. It is pointed out that China needs to improve the coastal hydrodynamic monitoring system, to solve the key problems in the coastal engineering construction under severe environment conditions, and to strengthen the management and ecological protection of coastal zones.
LONG-TERM RISE OF STORMINESS OF THE BALTIC SEA NEAR POLAND; POSSIBLE ORIGIN AND CONSEQUENCES
Authors: Rozynski Grzegorz Marcin , Pruszak Zbigniew
Published: October 2012

Long-term growth of storminess of the Baltic Sea near Poland has been identified for autumn and winter months, particularly for January. This growth is concurrent with the increase of westerly waves in Jan., Feb. and Oct. A vivid relationship between the North Atlantic Oscillation and significant wave height Hs in Jan. suggests it can be a potential driver of storminess growth in that month. For Feb. this relationship is unstable; other months demonstrate no connection toward the NAO. The wave climate in January also exhibits a strong 8-year cycle, very likely to drive 8-year variations of shoreline position, detected previously at a study site. The influence of NAO may manifest an unfavorable regime change in which mightier winter storms will be mostly occurring above freezing in the absence of ice cover. Without that cover vulnerable sandy beaches will be exposed to accelerated erosion from direct and stronger wave attack.
EVALUATION OF COASTAL RISK AT SELECTED SITES AGAINST EASTERN MEDITERRANEAN TSUNAMIS
Authors: Yalciner Ahmet Cevdet , Ozer Ceren , Karakus Hulya , Zaytsev Andrey , Guler Isikhan
Published: October 2012

Mediterranean, the center of civilizations since antiquity, experienced numerous earthquakes and triggered tsunamis. Historical information and distribution of fault zones, volcanoes and other probable tsunamigenic sea bottom deformations show that, there are source areas which may be considered as responsible for tsunamis in Eastern Mediterranean, Aegean, Marmara and Black sea region. These events affected the coastal structures that led to the loss of the economic power and social life of civilizations since antiquity. One of the probable examples of the earthquake or tsunami effects on the Fethiye town may be the eruption of Thera (also referred to as the Thera eruption or Santorini eruption). Another example of the earthquake or tsunami effects on the historical structures may be the destruction of lighthouse of Patara (Lykian City) harbor at the South of Turkey. The numerical modeling is one of the efficient tools for understanding the tsunami behaviors in the past. In this study, the historical data of earthquakes and tsunamis are evaluated together with the instrumental data of seismicity in order to select the tsunami source for modeling efforts. In modeling application, the most effective tsunami source among the others in Eastern Mediterranean is selected and simulated in order to better understand its possible effects on Fethiye town and the Patara (Lykian City). In this study, the simulation results are presented and dicussed for these selected regions.
COASTAL MANAGEMENT AND DISASTER PLANNING ON THE BASIS OF FLOOD RISK CALCULATIONS
Authors: Mertens Tina , Verwaest Toon , Delgado Rosalia , Trouw Koen , De Nocker Leo
Published: October 2012

Recent studies showed that one third of the Belgian coastline is not sufficiently protected against severe storm events. Therefore coastal protection plans are set up to assure a minimum safety standard for the entire coastline. Flood risk calculations constitute the main input parameter for the concept and planning phases. Since 100% safety can never be guaranteed, contingency plans are constructed to reduce the remaining flood risks. Flood risk calculations are a powerful communicative and operational instrument to use between engineers and experts on the field, thus forming the link between coastal management and disaster planning.
FAILURE PROBABILITY OF FLOOD DEFENCE STRUCTURES/ SYSTEMS IN RISK ANALYSIS FOR EXTREME STORM SURGES
Authors: Naulin Marie , Kortenhaus Andreas , Oumeraci Hocine
Published: October 2012

Extreme storm surges can cause failures of flood defences resulting in severe flooding of the hinterland and catastrophic damages. In order to quantify the risk of flooding an integrated risk analysis is being performed wherein one task is the determination of failure probabilities of flood defences. In this paper the failure probability calculations of flood defence structures and systems under the loading of extreme storm surges are reported. Moreover, the analysis of the breach and breach development is briefly introduced. Preliminary results of the failure probabilities and the breach modelling are presented using the example of the estuarine urban area of Hamburg, Germany. These results are put in context of an integrated risk analysis approach for extreme storm surges which is applied within an ongoing German joint research project.
EXAMINATION OF CLIMATE CHANGE ADAPTATION STRATEGIES
Authors: Kaiser Ralf , Knaack Heiko , Miani Marco , Niemeyer Hanz Dieter
Published: October 2012

Climate change adaptation strategies for coastal protection are examined with the help of mathematical models in the Ems/Dollart Estuary in consideration of different climate scenarios. The Ems Dollart Estuary is located at the Dutch German border in the southern North Sea, a coastal area which has suffered from enormous land losses due to medieval storm surges.
Since then the medieval retreat was partly reduced by successive land reclamation following the development of salt marshes.
PREDICTION OF STORM SURGE INTENSITY IN COASTAL DISASTER EVALUATION
Authors: Dong Sheng , Ji Qiaoling
Published: October 2012

In coastal area, serious storm surge disasters are frequently caused by the higher tidal level and concomitant huge wave heights toward shoreline. Qingdao is located at the southern tip of Shandong Peninsula of China. The storm surge disaster in Qingdao depends on various influencing factors such as the intensity, duration, and route of the passing typhoon. In order to make up the defects of the warning water level, a Poisson Bi-variable Gumbel Logistic Distribution is presented to predict storm surge intensity. On the basis of observed records of tidal level and simultaneously occurred wave height series that are sampled from typhoon processes in Qingdao coastal area of China since 1949, the return periods of typhoon surge are estimated by this model. Then a new criterion is put forward to classify intensity grade of disaster-induced typhoon surges. A practical case indicates that the new criterion is clear in probability concept, easy to operate, and fits the calculation of typhoon surge intensity. Thus the procedure with the proposed statistical model will be a reference for the disaster mitigation in the other coastal area influenced by typhoons.
STUDY ON INTERACTION BETWEEN THE ESTUARY DYNAMIC AND STORM SURGE INDUCED BY TROPICAL CYCLONE WINNIE(1997) IN YANGTZE RIVER ESTUARY
Authors: Zhang Jinshan , Kong Jun , Lei Zhiyi , Zhang Weisheng
Published: October 2012

ABSTRACT
This paper studied the interaction between the Estuary dynamic and storm surge induced by super tropical cyclone Winnie(1997) in Yangtze River Estuary with nested numerical model, which is driven by meso-scale meteorological model established. And the results indicate that, storm surges have significant influences on the Yangtze River Estuary. The maximum water level increase caused by storm surge can be monitored between Jiangyin and Xuliujing, whose exact position fluctuates owing to effects of the upstream runoff and estuarine tide. Furthermore the general laws about the relationships among astronomical tide, storm surge, and flood are revealed in this paper, and flood water level under storm surge events is predicted also.
NEAR-FIELD TSUNAMI HAZARD MAP PADANG, WEST SUMATRA: UTILIZING HIGH RESOLUTION GEOSPATIAL DATA AND RESEASONABLE SOURCE SCENARIOS
Authors: Schlurmann Torsten , Kongko Widjo , Goseberg Nils , Natawidjaja Danny Hilman , Sieh Kerry
Published: October 2012

Near-field tsunami propagation both in shallow water environments and bore-like wave propagation on land are conducted in this
study to obtain fundamental knowledge on the tsunami hazard potential in the city of Padang, Western Sumatra, Republic of
Indonesia. As the region proves a huge seismic moment deficit which has progressively accumulated since the last recorded
major earthquakes in 1797 and 1833, this investigation focuses on most reasonable seismic sources and possibly triggered nearshore
tsunamis in order to develop upgraded disaster mitigations programs in this densely-populated urban agglomeration located
on the western shore of Sumatra Island. Observations from continuous Global Positioning Satellite (cGPS) systems and
supplementary coral growth studies confirm a much greater probability of occurrence that a major earthquake and subsequent
tsunami are likely to strike the region in the near future. Newly surveyed and processed sets of geodata have been collected and
used to progress most plausible rupture scenarios to approximate the extent and magnitudes of a further earthquake. Based upon
this novel understanding, the present analysis applies two hydronumerical codes to simulate most probable tsunami run-up and
subsequent inundations in the city of Padang in very fine resolution. Run-up heights and flow-depths are determined stemming
from these most plausible rupture scenarios. Evaluation of outcome and performance of both numerical tools regarding impacts
of surge flow and bore-like wave fronts encountering the coast and inundating the city are thoroughly carried out. Results are
discussed not only for further scientific purposes, i.e. benchmark tests, but also to disseminate main findings to responsible
authorities in Padang with the objective to distribute the most probable dataset of plausible tsunami inundations as well as to
address valuable insights and knowledge for effective counter measures, i.e. evacuation routes and shelter building. Following
evacuation simulations based on rational assumptions and simplifications reveal a most alerting result as about 260.000 people
are living in the highly exposed potential tsunami inundation area in the city of Padang of which more than 90.000 people will
need more than 30 min. to evacuate to safe areas.
MODELLING SHORELINE EVOLUTION IN RESPONSE TO CLIMATE CHANGE
Authors: Zacharioudaki Anna , Reeve Dominic E
Published: October 2012

In this paper we examine the evidence for detectable climate change impacts on shoreline evolution. In a sequentially linked set of models, climate change scenarios are taken from atmospheric climate models and used to generate time slices of deepwater wave climate, nearshore wave climate and shoreline evolution. The models used are simple, containing the key physical processes only. Results are based on a hypothetical case which has some similarities to a site on the south coast of the UK. Output from the model is analysed using a robust statistical methodology to determine the evidence for statistically significant differences between beach behaviour under current conditions and several future scenarios. Statistically significant differences vary with season and also with the combination of climate model outputs used for input. Summers are the only season for which all models showed significant changes, corresponding to an increase in the net eastward littoral transport.
TREND MODEL OF SEA EXTREMES
Authors: Kitano Toshikazu , Kioka Wataru , Takahashi Rinya
Published: October 2012

The confidence interval for return level is re-examined. A definitively new method is proposed by employing an implicit link function, a plug-in estimation and a gamma distribution with the shape parameter given by the degree of experience. It is applied to a trend model of sea extremes, and it should be a very notable finding that the passing of time enlarges the range of confidence interval even for the stationary model.
EXPERIMENTAL STUDY INVESTIGATING VARIOUS SHOREFACE NOURISHMENT DESIGNS
Authors: Walstra Dirk-Jan , Hoyng C. W. , Tonnon P. K. , Van Rijn Leo C.
Published: October 2012

This experimental study focuses on the morphological development of a near-equilibrium profile on which to types of shoreface nourishments are placed. As previous studies have indicated that the efficiency of nourishments is mainly influenced by water depth in which they are constructed, two cross-shore locations are considered for an accretive and an erosive wave condition. A nourishment relatively high in the profile covering the trough and a nourishment relatively low in the profile just seawards of the breaker bar were investigated. Detailed measurements of wave height, velocities and sediment transport are combined with the observed morphological development to identify the processes that dominate the morphological development. The results confirm that the cross-shore location of nourishment has a major influence. The nourishment in relative deep water reduces the erosion of the upper part of the profile by about 20% for the accretive condition and 40% for the erosive condition. The nourishment higher in the profile results in a reduction of the erosion volume of 60% for both wave conditions.
BEACH NOURISHMENT IN CHINA: STATUS AND PROSPECTS
Authors: Cai Feng , Dean Robert G. , Liu Jianhui
Published: October 2012

Many beach nourishment projects have been performed in China over the last 2 decades since the first project was completed in 1990 in Hong Kong. The history and distribution of beach nourishment in China is summarized in this paper. Considering the development of nourishment design and public perceptions, the history of beach fill in China can be summarized into 3 stages. In general, this paper shows the characteristics of 4 types of nourishment projects based on different environmental conditions, 4 typical nourished sites for each type were selected and described in detail respectively. Considering the current research status in China, recommendations and suggestions for future development are outlined, including such aspects as construction of more and larger projects, development of beach management strategies, a beach nourishment manual, research efforts on numerical models for sediment transport and post-project monitoring and evaluation.
INTEGRATED BEACH MANAGEMENT AT IGEA MARINA, ITALY: RESULTS OF TEN-YEARS MONITORING
Authors: Preti Mentino , Zanuttigh Barbara
Published: October 2012

This contribution analyses the hydro-morphological effects induced by low crested structures confined by lateral groynes at Igea Marina beach, Northern Adriatic Sea, Italy. The site has been monitored since the works started for these last ten years. Results from bathymetric surveys, sediment samplings, video monitoring and numerical modelling are presented and discussed.
ASSESSMENT OF ALTERNATIVE BEACH PLACEMENT ON SURFING RESOURCES
Authors: Miller Jon K , Mahon Alicia M , Herrington Thomas O
Published: October 2012

The beach fill was constructed using an innovative feeder beach design, rather than a standard linear fill template. The feeder beach design was adopted to address the concerns of local surfing groups by initially burying fewer structures, and by potentially creating additional surfing opportunities through enhanced bar formation during the equilibration process. Nine months of monitoring results show that roughly 84% of the placed material can be accounted for within the project area and on the downdrift beaches. The immediate impact of the fill on the local surfing conditions was negative within the project area as steep slopes, violent plunging breakers, and narrow surfzones limited the use of the feeder beach area; however traditional surf spots to the north and south were unaffected by the nourishment due to the concentrated nature of its placement. More recently, as the post-nourishment slopes have begun to equilibrate, surfing conditions have improved markedly within the project area, while the up drift and down drift beaches remain relatively unaffected.
" SAND ENGINE " : BACKGROUND AND DESIGN OF A MEGA-NOURISHMENT PILOT IN THE NETHERLANDS
Authors: Mulder Jan P.M. , Tonnon Pieter Koen
Published: October 2012

Coastal policy in the Netherlands is characterised by three scale levels. The smallest scale is aimed at the preservation of safety agaisnt flooding by maintaining a minimum dune strength; the middle- and large scales at preservation of sustainable safety and of functions in the coastal zone by maintaining the coast line, respectively the sand volume in the coastal foundation. The definition of three scales basically implies a pro-active approach, based on the idea that the larger scale sets boundary conditions for the smaller scale. This pro-active approach appears to be succesful: nourishments since 1990 not only have resulted in maintaining the coast line, but also in an extension of the dunes, contributing to an increased safety against flooding. The succes has been achieved by a yearly nourishment volume of 12 Mm3.
Recent studies have indicated the need to upscale the yearly averaged nourishment volume. A recent update of the sediment balance of the coastal foundation shows a negative total of ca. 20 Mm3 per year; so apparently 12 Mm3 nourishments per year is insufficient to maintain the total active sand volume of the system. Besides, in a study on future adaptation options to climate change in the Netherlands, the authoritive Deltacommissie (2008) even recommends a raise of nourishment budgets up to 85 Mm3/year until the year 2050, taking into account an ultimate worst case scenario of a sea level rise of 13 cm in 2100.
To investigate innovative ways of nourishing larger volumes of sand, a Pilot project Sand Engine has been developed. The pilot implies a mega-nourishment of approximately 20 Mm3 (~ 10000 m3/m) on the coast of Holland, between Hook of Holland and The Hague. In the design phase of the pilot, a morphodynamic Delft3d model has been used to calculate morphological effects of several alternatives. The Environmental Impact Assessment EIA has decided on a shore attached cross shore bar with a length of ca. 1.5 km, as the preferent alternative. Implementation is planned for 2011, starting december 2010.
DESIGN OF A COASTAL PROTECTION SCHEME FOR ADA AT THE VOLTA-RIVER MOUTH (GHANA)
Authors: Bollen Mark , Trouw Koen , Lerouge Frederik , Gruwez Vincent , Bolle Annelies , Hoffman Bernhard , Leysen Gert , De Kesel Yann , Mercelis Peter
Published: October 2012

The coastal town Ada in Ghana is threaded by a severe coastal erosion. A protection scheme has to be designed to protect the town. Since the area is ecologically important, e.a. due to the presence of turtles, both during the design process and during the construction phase actions to diminish possible negative effects have to be considered. The design is supported by measuring campaigns and numerical modeling of the currents, waves and morphology
APPLICATION OF A SIMPLE HYDRODYNAMIC MODEL TO ESTUARY ENTRANCE
Authors: McLean Errol J. , Hinwood Jon B.
Published: October 2012

Tidal inlets which link a tidal basin to the sea via a constricted entrance are common on the south-east Australian coast. Closure, or even significant constriction, raises water levels but restricts tidal range within the basin, while open entrances provide regular and significant tidal exchange with the ocean. A rapid assessment procedure with minimal data requirements has been shown to be informative for monitoring and a useful component of any Decision Support System set up as part of a management structure. Such a system is presented in this paper. It is based on one permanent water level gauge inside the inlet plus the use of a simple, first-order hydrodynamic model to relate the tide range, mean water level and river flow to the inlet cross sectional area. The method is tested against data from the
Snowy River Estuary in south-eastern Australia but would be suitable over a range of estuaries. In addition, the framework presented can also provide a mechanism to explore conditions over the range of expected data, thus allowing better selection of model schematization and runs in estuarine systems where the use of 2 or 3D modeling can be justified.