bluuebunny/crossref_metadata_2025 huggingface dataset:
FUTURE FLOODING OF THE VOLTA DELTA CAUSED BY SEA LEVEL RISE AND LAND SUBSIDENCE
Authors: Brempong Emmanuel K. , Almar Rafael , Angnuureng Donatus , Mattah Precious Agbeko D. , Jayson-Quashigah Philip-Neri , Appeaning-Addo Kwasi
Published: September 2023

The Volta delta(Ghana, West Africa) is increasingly impacted by sea level rise (SLR). SLR makes the Volta delta mostly vulnerable to flooding, salinization of water resources and agriculture fields, and permanent loss of lands. This would potentially threaten and present a growing risk to its population, infrastructure and economy, and even worsen due to land subsidence (LS). Relative sea level rise (RSLR) in this study is the rate of LS with respect to SLR. It is thus very important to precisely quantify LS rates together with SLR as well as planning and assessment of countermeasures. This study is in two parts, The first study presents and discusses recent LS rates in the Volta delta derived from satellite-based SAR-Interferometry and their impact on relative SLR. The second study, also assesses major hydrodynamic parameters (Wave runup, Sea Level Anomaly,tide and atmospheric conditions) that play a role in extreme coastal flooding events.
PARTICIPATORY APPROACH TO ASSESS COASTAL EROSION MITIGATION AND CLIMATE CHANGE ADAPTATION MEASURES
Authors: Lima Márcia , Coelho Carlos , Alves Filipe , Vizinho André
Published: September 2023

The economic and social importance of coastal areas combined with their growing erosion problems and climate change impacts allows anticipating an increase in investments in these areas. In the past, strategies to mitigate territorial losses or property damage have been mainly reactive, non-inclusive, non-participatory, and locked-in technical solutions. Moreover, cost-benefit assessments of Coastal and Climate Change Adaptation (CCA) plans are still scarce, underused and poorly understood. So, the goal of this work is to contribute to a complete characterization of coastal erosion mitigation and climate change adaptation strategies and their implementation measures by considering a participatory approach that integrates medium to long-term perspectives, combining, simultaneously, social, environmental, economic and engineering dimensions, to help decision-makers implementing sustainable future-proof CCA strategies.
PROBABILISTIC FORECASTING SYSTEM OF STORM SURGE USING A STOCHASTIC TYPHOON MODEL
Authors: Tajima Yoshimitsu , Higaki Yukimasa
Published: September 2023

This paper presents a newly developed real time probabilistic forecasting system of storm surge at an arbitrary target location when a typhoon is formed and approaches to the location. Such probabilistic information may be essential for business or public entities along the coast who need to make appropriate decision to what extent they should break their daily operations and prepare for the upcoming coastal hazard. Developed system, based on Monte Carlo simulation, consists of two parts: (i) generation of a number of virtual typhoons; and (ii) storm surge prediction for each typhoon.
FIELD SURVEY OF THE 30 OCTOBER 2020 SAMOS (AEGEAN SEA) TSUNAMI IN THE GREEK ISLANDS
Authors: Synolakis Costas , Kalligeris Nikos , Skanavis Vassilios , Charalampakis Marinos , Melis Nikolaos , Voukouvalas Evangelos , Annunziato Alessandro
Published: September 2023

On October 30th, 2020, a magnitude 7.0 earthquake struck offshore from the northern coast of Samos, Greece, generating a tsunami that impacted the nearshore Greek islands and the Aegean coastline of Turkey. The 2020 Samos (Aegean Sea) tsunami is arguably the most significant event in the Aegean since the 09 July 1956 Amorgos earthquake and tsunami that produced runup values as high as 20 m on the south coast of Amorgos (Okal et al., 2009). Maximum runup reached 3.8 m along the Turkish coast (Dogan et al., 2021), and ~3 m on the north coast of Samos Island (Kalligeris et al., 2021). We present detailed results from several post-event field surveys, and report first wave arrival timing and polarity information as well as tsunami height/runup measurements, from five islands.
ECOENGINEERING FRESHWATER FLOWS FOR ESTUARY HYDROLOGICAL STATE
Authors: Gallop Shari L. , Bryan Karin R. , Hamilton David P. , Foley Melissa , Largier John L.
Published: September 2023

The quantity, quality and timing of freshwater inflow into estuaries is critical to support estuarine ecosystem health. However, most estuaries are affected by upstream manipulation of freshwater inflows. Coinciding with the United Nations Decade of Restoration (2021–2030), there is great interest in re-creating functional estuarine ecosystems, including by modifying the physio-chemical characteristics with the premise that a functional ecosystem will follow (ecoengineering). To restore estuarine ecology, the physical processes of the system must first be conductive to supporting the re-establishment and sustenance of biota. These physical processes are generally under-monitored and often not used as a measure of restoration success. We explore ecoengineering to restore freshwater inflows to estuaries, focused on hydrological state. We use the Pressure—State—Response (PSR) framework to set the context for this review.
MORPHOLOGICAL RESPONSE OF THE NEARSHORE SEABED DUE TO OFFSHORE PRECONDITIONING FEATURES
Authors: Mead Shaw T. , Atkin Edward A.
Published: September 2023

Nearshore submerged structures for coastal protection are being applied in increasing numbers worldwide, with Multi-Purpose Reefs (MPR’s) also becoming a favoured approach. MPR’s look to combine coastal protection through the dissipation of wave energy offshore and a consequent increased beach width, marine habitat/ecological enhancement, and public amenity (e.g., diving, snorkelling, surfing, etc.). However, while there have been improvements in performance with respect to the addition of surfing amenity by using traditional construction methods (e.g., large rock such as used to construct the MPRs in Borth, Wales and Palm Beach, Australia), there are still issues of high design tolerances and challenging construction conditions close to the beach on exposed coasts. This work continues research regarding offshore preconditioning features; the companion manuscript to this work takes an iterative design approach to establish the relationships between preconditioning features and surf zone response using the parameters of peel angle as a proxy for surfing wave quality (Atkin et al., 2019). This work adds to the literature base of our theoretical understanding of the integration of coastal protection and surfing amenity.
FROM EXPERIMENT TO INTERVENTION: SCALING UP MARINE ECO-ENGINEERING
Authors: Pinto Mariana Mayer , Bishop Melanie , Dafforn Katherine , Vozzo Maria
Published: September 2023

We use lessons learned from more than 20 years of eco-engineering projects in Sydney Harbour to present a pathway for how to connect science and scientific findings to inform management interventions and policy, to optimize and facilitate the scaling up of eco-engineering worldwide. We use the Living Seawalls, a large-scale eco-engineering project, as a case-study. Living Seawalls comprise modules, mimicking the habitat features of natural shorelines (e.g. rock pools, crevices; Fig. 1) that are fitted in scalable mosaics onto built structures. The complex surfaces increase the habitat area for growth of marine life (Bishop et al, in press).
EFFECTIVENESS OF TSUNAMI MITIGATION STRUCTURES ON UNDERUTILIZED URBAN AREAS: A CASE STUDY ON REDUCING DAMAGE CAUSED BY TSUNAMI TO BUILDINGS
Authors: Yamanaka Ryoichi , Mikami Taku , Takino Moe , Baba Toshitaka , Nakagawa Kosuke , Kozuki Yasunori
Published: September 2023

There are concerns that a Nankai Trough Mega Earthquake may occur soon, and may cause widespread damage. This demands not only functional enhancement of seacoast environments, but also pre-disaster recovery planning that includes evacuation drills and securing evacuation sites in coastal areas. One of the most effective measures for this is relocation to higher ground in urban areas. However, financial restrictions and topographical conditions do not make relocation to higher ground easy. Thus, new countermeasures must be investigated that can facilitate early recovery and reconstruction. We believe that reducing the collapse and washing away of buildings due to tsunamis in densely populated areas could be one of the ways to approach this problem. Here, we find that the risk of building collapse and washing away depends on the type of building1) and inundation height. Thus, inundation due to tsunami must be lowered to avoid the low risk of collapse or wash away. Therefore, we look at the example2) of Miyagi Prefecture amid the lessons of the Great East Japan Earthquake, and expand upon the idea of multiple countermeasures to cover the urban areas. Specifically, low-lying underutilized lands in urban areas must be utilized to provide multifunction disaster prevention facilities enabling multiple countermeasures. Based on the above-mentioned points, the purpose of the present study is to propose multiple tsunami countermeasures for urban areas and numerically investigate their effects. Thus, we conducted a case study in a port town with a small river, which is an area where disasters are a concern.
AN ADAPTIVE PATHWAY TO COASTAL RESILIENCE
Authors: Hosking Adam , Lany Peter von , Clifton Craig , Pontee Nigel
Published: September 2023

The sustainability of our coastal communities and economy is depend upon extensive systems of human and natural infrastructure. These systems need to be reliable, resilient to extreme events and adaptive to future changes in economic and environment conditions as well as adaptable to potential future climate change. In making long term decisions, it is important to make and implement choices that are robust and adaptive. This paper considers approaches being adopted to deliver confidence in coastal management decision making, while providing the scope to adjust course as necessary in the face of future climate.
DIGITAL TWINNING AS A DECISION SUPPORT TOOL FOR RESILIENCE PLANNING OF COASTAL INTERMODAL TRANSPORTATION NETWORKS
Authors: Tafur Anibal , Padgett Jamie E.
Published: September 2023

Intermodal freight transportation networks (seaport-road-rail) constitute the economic backbone of coastal communities. From the current state of the literature, it is observed that despite their importance, intermodal transportation networks remain unserved with comprehensive tools that support high-level planning for resilience of existing and future infrastructure under hurricane scenarios. To address these gaps, this paper proposes the implementation of a decision support tool based on digital twinning, which is able to predict system performance in terms of resilience, given three main inputs: hazard intensities, budgetary constraints, and the characteristics and topology of the network.
DEVELOPMENT OF SMARTPHONE APPLICATION TO SUPPORT TSUNAMI EVACUATION
Authors: Han Dawn Chenxi , Takabatake Tomoyuki , Esteban Miguel , Shibayama Tomoya
Published: September 2023

Kamakura is a historical city situated along the Japanese coastline, which is at risk of being devastated by a tsunami due to its relatively flat topography and proximity to the Sagami and Nankai Troughs. Evacuation would play an important role to reduce the potential loss of lives resulting from a tsunami event. While carrying out evacuation drills is helpful to enable participants to take appropriate responses during an actual tsunami event, it is not realistic for all the residents to participate in such drills. Furthermore, as some coastal areas are renowned sightseeing spots, there might be many visitors who do not know the area well and struggle to evacuate in the event of a tsunami (Takabatake et al., 2017; 2020). Thus, the authors developed a smartphone application (App) that supports swift tsunami evacuation, which can be especially helpful for those who do not have sufficient knowledge about evacuation routes and refuge places. The present study aimed to investigate the effectiveness of the developed app, and to clarify its impact on people’s decision making with regards to evacuation behavior.
TSUNAMI MODELLING IN A BUILT-IN COASTAL ENVIRONMENT WITH ADAPTIVE MESH RIFINEMENT AND VARYING BOTTOM FRICTION
Authors: Aljber Morhaf , Nogami Kaho , Jeong Jae-Soon , Cabrera Jonathan Salar , Lee Han Soo
Published: September 2023

The great Japan earthquake on March/11/2011provoked an extreme tsunami wave toward the northeastern Japanese coast. The tsunami inundation covered a wide range of territories stretching over 500 km2 and caused devastating influences that claimed more than 15,000 lives (Mori et al. (2011)). Miyagi Prefecture, the closest mainland to the epicentre, received massive tsunami waves that reached over 40 m in run-up height. Prasetyo et al. (2019) aimed to reproduce the tsunami wave inundation in Onagawa Town of Miyagi Prefecture by building a physical model using Hybrid Tsunami Open Flume in Ujigawa Open Laboratory (HyTOFU) at Kyoto University to study the inundation process by measuring the wave height and arrival time. For that purpose, two wave types were used, the (Pump-type) hydraulic bore, and the (Piston-type) solitary wave. Also, 2D and quasi-3D (Q3D) models were tested for their robustness and applied to emulate tsunami propagation in the complex coastal city model. In this study, we adopted adaptive mesh refinement (AMR) for its efficiency in tsunami modelling with Basilisk open-source flow solver for non-linear shallow water (Saint-Venant) equations and fully non-linear Boussinesq (Green-Naghdi) equations (Popinet (2015)). The numerical experiment was conducted to validate the model by comparing the wave height with the physical model experiment, the 2D, and Q3D model results by Prasetyo et al. (2019).
MIGRATION AND BURIAL TENDENCIES OF VARIABLE DENSITY MUNITIONS: INITIAL RESULTS FROM A LARGE-SCALE STUDY
Authors: Gangadharan Manoj Kumar , Idowu Temitope E , Chapman Emily , Puleo Jack A , Stolle Jacob , Bang Damien Pham Van
Published: September 2023

Past military activity close to the coast has discarded numerous ordnances in the nearshore environment. These ordinances (some of them unexploded; also called UXOs or munitions) are transported by waves and currents and may become exposed on beaches. The increased intensity of storm events may lead to a subsequent increase in UXO exposure and migration. Prolonged exposure of UXOs to ocean conditions leads to surface growth that alters their bulk density. Hence, it is essential to understand the influence of bulk density on mobility characteristics. This study, funded by the Strategic Environment Research and Development Program (SERDP), aims to quantify the processes that affect the mobility and burial of variable density munitions in the surf and swash zones during scaled extreme forcing.
MULTIVARIATE COASTAL FLOOD RISK ALONG THE US PACIFIC
Authors: Lucey Joseph , Gallien Timu
Published: September 2023

Urban coastal flooding is an increasing humanitarian and socioeconomic hazard. Flood assessments do not typically consider multivariate (marine and hydrologic) and multi-pathway (e.g., precipitation-surge, overtopping- overflow, surface–sewer) flooding, which may amplify coastal hazards and vulnerability. Notably, flood extent is underestimated when compounded hydrologic and marine impacts are not considered (Chen and Liu, 2014). Previous multivariate flooding studies typically consider the joint impacts of storm surge and fluvial sources. This study explores multivariate flooding caused by marine water levels, precipitation, and waves along the U.S. Pacific Coast while considering uncertainties in data sampling, precipitation source, record length, and distribution selection impart on risk estimates.
IDENTIFICATION OF POTENTIAL STORM SURGES DUE TO TYPHOON RAI USING NUMERICAL MODELS
Authors: Valdez Justin Joseph , Shibayama Tomoya
Published: September 2023

In December 2021, Typhoon Rai (local name: Odette) hit the Visayas region of the Philippines. It had a minimum sea level pressure (MSLP) of 915 hectopascals (hPa) and a maximum sustained wind speed of 54.02 m/s and was classified as a violent typhoon by the Japan Meteorological Agency. Rai caused massive damage to infrastructure and housing (NDRRMC 2022). Rai passed through the vulnerable islands of Bohol and Cebu, where high storm surge heights could be expected from strong typhoons (Lapidez et al., 2015). Field surveys were conducted right after a typhoon event to investigate the condition of the affected areas. However, Rai hit during the pandemic when travel restrictions were effective in the country. Thus, it was difficult to identify the areas hit by potential storm surges immediately. Satellite imagery is one method; however, it is generally difficult to identify if the area was affected by storm surges using images. Numerical modeling of the typhoon event over select areas is one way to solve the problem of disaster information shortage. In this study, Rai is simulated using weather and storm models over the provinces of Bohol and Cebu.
ASSESSING A COST-EFFICIENT METHODOLOGY FOR LONG TERM WAVE COMPUTATION
Authors: Besio Giovanni , Leo Francesco De , Orfila Alejandro , Enriquez Alejandra
Published: September 2023

We compare two approaches for the computation of return period wave in shallow waters: 1) Perform Extreme Value Analysis (EVA) on offshore wave data and propagate design waves toward the coast (approach referred to as DW-EVM), and 2) Propagate the whole time-series to the coast first, then compute EVA on the downscaled data (referred to as SW-EVM).
COMPOUND URBAN COASTAL FLOOD MODELING: INTEGRATING TIDE, WAVES, PRECIPITATION AND HYDRAULIC INFRASTRUCTURE
Authors: Tang Boxiang , Gallien Timu W.
Published: September 2023

Compound coastal flooding considers the joint impacts of marine and hydrologic interactions and has recently been identified as an international research priority. Along the US West Coast, winter storms often bring high marine water levels along with energetic waves and precipitation. Hydrodynamic models have been widely used to estimate flood impacts, including extreme estuarine water levels in compound events (e.g., riverine discharge-tide-storm surge interactions), and produced satisfactory results. However, few studies further consider overland flow routing and high-resolution flood mapping in highly urbanized, low-lying coastal areas. Here, an integrated Delft3D-FM based numerical modeling framework is used to explicitly resolve multi-pathway flood processes (i.e., high marine water levels, waves overtopping, precipitation) and infrastructure (e.g., seawalls, storm drains, artificial dunes).
PREDICTION OF TOPOGRAPHIC CHANGES ON ENSHU-NADA COAST CONSIDERING EFFECT OF BOTH WAVES AND WINDBLOWN SAND
Authors: Yokota Takuya , Uda Takaaki , Kobayashi Akio , Noshi  Yasuhito
Published: September 2023

The morphology of sand dunes formed on the Maisaka and Hamamatsu coasts facing the Enshu-nada Sea was investigated by field observation. The development of sand dunes was numerically predicted using a model predicting the effect of both waves and windblown sand. In the field observation, the development of sand dunes with a rhythmic shape similar to a sand spit was observed in the backshore area. It was found that pine trees died in the area with a narrow sand dune owing to wave run-up and the dispersion of salinity during storm wave conditions. In the numerical simulation, the formation of sand dunes was successfully reproduced under the condition that the predominant wind blew at a large angle relative to the direction normal to the shoreline.
APIA PORT BREAKWATER RECONSTRUCTION
Authors: Satterthwaite Kane , Andrews Connon
Published: September 2023

Samoa is located in the South Pacific Ocean, about halfway between Hawaii and New Zealand. The first wharf at Apia (185m long) was constructed in 1966 and a 100m long breakwater with 8t Dolos armor units was constructed in 1988-89 to provide shelter. Following large cyclones in the early 1990s, the breakwater was rehabilitated in 1996 with larger 20t Dolos armor units. In 2003 a solid concrete crown wall added to the breakwater to mitigate wave transmission into the harbor. There is limited toe and scour protection and multiple units have broken legs, cracks and rust stains from corroding steel reinforcement. The design intent of the breakwater upgrading project is to improve resilience to extreme climatic and natural disaster events. Reconstructing the breakwater with a higher crest, larger roundhead, new concrete armor units, toe support and a scour apron was selected as the most appropriate option to meet the design criteria. Physical modelling was undertaken to verify and optimize the design. Wave calibration indicated good correlation with numerical modelling and showed that for offshore wave heights of ~11.5m and greater the near structure wave height is depth limited (Hs ~9.1m). The physical model testing indicated that the existing 20t Dolos units on the rear slope are unstable under the 1percent AEP event as the base units have limited rock toe support. Further model testing was undertaken using 16m3 Xblocs on the leeside which was successful and detailed design was completed accordingly.
BIOMIMICRY OF NATURAL REEF HYDRODYNAMICS IN AN ARTIFICIAL SPUR AND GROOVE REEF FORMATION
Authors: Wissmach Emilee , Ninesling Matthew , Weaver Robert J.
Published: September 2023

An artificial spur-and-groove (SAG) reef formation designed to perform as a submerged breakwater was studied. Not only do natural SAG reefs effectively attenuate waves, but they also create important circulation within the system that encourages the success of corals and the overall ecosystem. Modular components were developed and imported into the CFD software FLOW-3D® HYDRO to test the wave-structure interaction while adjusting the geometry of the structure, wave conditions, and depth due to tidal changes in environmental conditions similar to Moloka’i, Hawaii. Results showed highest wave height reduction with larger wave heights as well as lower submergence during low tide conditions.
A PROCESS-BASED NUMERICAL MODEL OF SHOREFACE PROFILE EVOLUTION
Authors: Patterson Dean , Nielsen Peter , Calaghan David , Baldock Tom
Published: September 2023

It remains a challenge to model numerically profile evolution across the shore-face from deep water to the shoreline with stability and accuracy. At long time scales, attempts to date typically utilise equilibrium profile shapes or bed slopes, with profile change based on the degree of disequilibrium and wave/current forcing, primarily for the surf zone in erosion events. Simulation of shoreward bar migration and beach recovery after erosion events is generally poor. Here we present an effective integrated framework and process-based dynamics in the form of a new software package that successfully models the whole shore-face zone seamlessly from relative deep water to the beach. It incorporates analytical procedures, including some simplified empirical relationships, that describe the forcing of waves and currents and the sedimentation responses that change the profile. It is shown to simulate profile evolution satisfactorily, with shoreward as well as seaward sand transport, bar development and migration and beach erosion and accretion, in a manner and at time-scales consistent with measured data, for both small scale laboratory and prototype modal and storm conditions. The model caters for water level variations due to tide, storm surge and/or sea level rise. It may be used to assess beach nourishment deposition at the beach berm, lower shore-face or across the surf zone.
CLIMATE CHANGE IMPACTS ON REEF TOP ISLANDS
Authors: Bettington Stuart , Baldwin David
Published: September 2023

It is generally understood that climate change, particularly sea level rise, is a threat to communities and habitats on low lying tropical islands. However, the full nature of this threat is not well understood. These islands have been created by met-ocean forces on the reef platforms and represents the culmination of a dynamic balance between these forces and the supply of sediment over thousands of years. This paper assesses the impact of climate change on the reef top hydrodynamics and coastal morphology of reef top islands.
LABORATARY STUDY OF THE VERTICAL RETREATING SAND WALL OBSERVED IN COASTAL FLOW SLIDES
Authors: Man Xiamei , Callaghan David P , Nielsen Peter
Published: September 2023

Coastal flow slides have been reported around the world (Mastbergen et al., 2019; Nédélec et al., 2022), often at over-steepened banks subject to strong tidal flows, pose threat to coastal communities and infrastructure (Lulla, 2017). With sea level rise caused by climate change, these flow slides are expected to occur more frequently in more sites worldwide. Amity Point Beach, North Stradbroke Island (27o 23’ 35’’S, 153o26’23’’E), about 40 km from Brisbane, Australia, have experienced regular coastal flow slides for more than 40 years (Eberhardt, 1978). Together with observations at Amity Point beach field site, small-scale flow slides are simulated in laboratory by tilting metal box filled with sand and fluid.
TURBULENT BORES–INDUCED SCOUR AND PORE PRESSURE VARIATIONS AROUND A VERTICAL STRUCTURE
Authors: Rajaie Marieh , Nistor Ioan , Rennie Colin D. , Azimi Amir H. , Hoffmann Tom
Published: September 2023

The scour due to the highly turbulent tsunami inundation is also a major threat to nearshore infrastructure [Nakamura, et al., 2008]. Research on local sediment erosion during tsunami events has shown a correlation between scour formation, pore pressure variations, and soil liquefaction [Mioduszewski and Maeno, 2003]. To understand the structures’ capacity to withstand the tsunami bores, it is critical to assess scour formation and pore pressure variations around their foundations [Macabuag et al., 2018, Nicholas et al., 2020; Mehrzad et at. 2021]. Young et al. (2008) conducted laboratory experiments to study tsunami induced liquefaction failure on a sand bed with two different slopes of 1V:5H and 1V:15H. The correlation between soil liquefaction and scour showed a direct link with bed slope and pore pressure and the peak pressure increased as the bed slope increased. Concerning the hydrodynamic forcing factor, research conducted by [Chanson, 2006] showed that the hydrodynamic characteristics of tsunami inundation can be adequately modeled using dam-break waves. The prime objective of this study was to comprehensively investigate the interaction of a wide range of hydrodynamic conditions and beach slopes on the variation of the pore pressure and associated scour.
MORPHODYNAMICS AT THE MOUTH OF A BAR-BUILT ESTUARY: CARMEL RIVER, CA, USA
Authors: Orescanin Mara M. , Montoya Liliana Velasquez , Plant John , Williamson Cynthia , Brennan Collin
Published: September 2023

Bar-built estuaries (BBEs), also known as Intermittently Closed Estuaries (ICEs), are common to coastal climates with a strong seasonal precipitation pattern and waves including the US West Coast, Australia, South Africa, and Western Europe (McSweeney et al, 2017). In California, USA, these BBEs typically go through seasonal morphological transitions from a closed state to open state as precipitation increases during the winter months. However, timing of these events is challenging owing to variable behavior for given environmental forcing conditions, and as a result often lead to intermittent flooding of the surrounding areas that is difficult to predict (Behrens et al., 2013; Orescanin and Scooler, 2018). This study uses a compilation of observations using in-situ moorings, topographic beach surveys, and remote sensing from unmanned aerial systems (UAS) to assess rates of morphological change at the Carmel River, CA, USA.
IMPACTS OF SLR-UPSCALED NOURISHMENT SCENARIOS ON DECADAL CROSS-SHORE DYNAMICS
Authors: Kettler Tosca , Schipper Matthieu de , Luijendijk Arjen , Aarninkhof Stefan
Published: September 2023

Projections of high rates of sea level rise have stimulated proposals for adaptation strategies with increasingly high nourishment volumes. Nourishment strategies involving higher sand volumes can be accomplished by increasing the volume of individual nourishments or by decreasing the time interval between successive nourishments. The optimal placement of the sediment volumes in the cross-shore and alongshore to attain our coastal management goals is still under debate. From a long term, large scale perspective only the added sediment volume may be considered, regardless of the placement. A widely accepted perception is that coastal profiles respond to nourishment by rapid equilibration to an equilibrium shape including the added sand volume. However, the timescale of the redistribution of the sediment may be slower than the desired spreading rate of the added sediment, causing sediment to accumulate at some parts of the profile, while leaving other elevations sediment starved. This research aims to examine decadal-scale coastal profile response to nourishment strategies upscaled with sea level rise (SLR) whereby potential nourishment strategy impacts for beach width (fluctuations), dune growth potential and momentary coastline are mapped.
MORPHOLOGICAL CHANGES TO THE PORTSEA (VICTORA) COASTLINE FOLLOWING SHIPPING CHANNEL DEEPENING
Authors: McCowan Andrew , Brøker Ida
Published: September 2023

Portsea Beach is located on the south side of Port Phillip Bay approximately 55 km south of Melbourne and 6 km east of Point Nepean at the Entrance to the Bay. Portsea Beach experienced significant erosion in 2009 and 2010. The erosion occurred shortly after the dredging that was carried out as part of the Port of Melbourne’s “Channel Deepening Project” to deepen the shipping channel that provides access to the Port of Melbourne. The erosion at Portsea did not occur in isolation. Since 2009, there has also been significant on-going erosion along Nepean Bay Beach to the west, and significant accretion along Shelley Beach and Point King Beach to the east.
FIELD OBSERVATIONS OF TURBULENCE AND SUSPENDED SEDIMENTS OVER AN INTERTIDAL REEF
Authors: Huang Zhi-Cheng , Nguyen Ly Trung
Published: September 2023

Sediment suspension and sedimentation affect coral reef ecosystem by altering physical and biological processes. In general, sediment suspension is controlled by the hydrodynamics of turbulence in reef systems (Pomeroy et al., 2017). The structures of colonies increase roughness and enhance turbulence mixing in coral reefs, which might affect sediment suspension. However, such complex processes between the sediment suspension and turbulence in natural reef systems are not well understood. Here, we present field observations of turbulence and suspended sediment concentration (SSC) over an intertidal reef flat. This research aims to understand, quantify, parameterize, and study the physical process of SSC variations, and, to investigate how the turbulence affecting the variation of SSC on the reef flat.
HYDRODYNAMIC CLASSIFICATION OF ESTUARIES: CHALLENGES AND ALTERNATE APPROACHES
Authors: Power Hannah E. , Broadfoot Madelaine S. S. , Palmer Karen , Hanslow David J.
Published: September 2023

Globally, estuaries are environments that are under increasing stressors from dense populations, pollutants, and changing ecosystems with pressures only likely to increase with climate change. Estuaries are systems with widely variable morphology that are typically spatially vast and highly dynamic, hence site-specific investigation is often costly and practically challenging. As such, conceptual approaches that allow the translation of information from one estuary to another due to similar classifications in conceptual models are widely used for management purposes. This paper will use case study examples to identify challenges associated with the current categorical estuary classification schemes and suggest alternate approaches that capture the varying dynamics of the full spectrum of estuary systems.
WAVE TRANSMISSION AND DISSIPATION BY HYBRID (VEGETATED WITH MANGROVE) BREAKWATERS
Authors: Partida José , Mendoza Edgar
Published: September 2023

In recent years a group of studies for coastal protection (Hashim and Catherine (2013), Maza et al. (2018), Tomiczek et al. (2020), among others) have been carried out to determine drag coefficients in mangrove forests due to ocean waves. Following the mangrove hybrid platform concept by Tagaki (2019), and actual projects such as the mangrove rehabilitation site in the Jakarta Fishing Port, the main objective of this study was to propose and test a hybrid structure capable of controlling wave energy via breaking and dissipation. The experimental tests focused on determining the rates of the wave energy distribution (reflection, transmission and dissipation) due to the presence of an afforested mangrove zone in the upper part of the breakwater. A fixed-bottom small-scale model was tested under normal and extreme marine regimes. The prototype dimensions of the breakwater are total height 5.70 m, crest width 10 m, seaside slope 2:1 (H:V) and leeward slope (1.5:1). The barrier is composed of a rigid bottom built of artificial elements (cubipods) and a long crown intended to be vegetated (with red mangroves, for example). The rationale behind this configuration is to provide ecosystem services by an artificially built mangrove forest protected by the rigid bottom. The experimental program consisted of 54 experiments divided into 7 groups corresponding to regular and irregular waves, mean and extreme and high and low tide conditions. Other variables of interest were the density and spatial distribution of mangroves, such as core materials.
COMPARING RESPONSE-BASED AND EVENT-BASED OVERTOPPING DESIGN
Authors: Stehno Abigail L. , Gonzalez Jeffrey A. Melby, Norberto Nadal-Caraballo, Victor
Published: September 2023

Coastal structure crest elevations are routinely designed to a specific hazard level. In the U.S., for example, levee crest elevations often correspond to the 1 percent annual exceedance probability (AEP) overtopping rate at 90 percent confidence level (CL). Statistical methods to compute coastal structure response range from simply inputting wave and water level forcing conditions at a certain AEP into a response equation (i.e. event-based or frequency-based approach) to a fully stochastic Monte Carlo numerical simulation where thousands of storm responses are sampled and epistemic uncertainties incorporated (i.e. response-based approach). Event-based approaches oversimplify both statistics and physics; however, time, cost, and complexity can limit application of the response-based simulation. Response-based stochastic simulation approaches tend to more realistically characterize structure responses. Herein we compare common frequency-based and response-based stochastic approaches for levee and floodwall overtopping design. For frequency-based approaches, structure responses are computed using wave and water level forcings at a given AEP, and for response-based approaches, a large number of storms are sampled in a Monte Carlo simulation.
NUMERICAL INVESTIGATIONS OF HYDRODYNAMIC CHARACTERISTICS OF A MARINEFOULED SUBMERGED FLOATING TUNNEL
Authors: Zou Pengxu , Ruiter Niels , Bricker Jeremy , Uijttewaal Wim S.J.
Published: September 2023

Marine biofouling is a major concern in the operational performance of submerged floating tunnels (SFTs). Within years after construction, marine growth increases the effective dimension and mass of the SFT and hence, can substantially affect the hydrodynamic forces and alter the buoyancy-weight ratio (BWR). Therefore, roughness height is one of the most crucial factors influencing the hydrodynamic performance of the SFT. We investigated the effects of marine fouling and flow behavior around the SFT with varying roughness properties at different Reynolds numbers. Furthermore, the cross-section geometry of an SFT has a significant effect on flow behavior. In this study, the influence of increased surface roughness as caused by marine fouling on an SFT is investigated using Computational Fluid Dynamics (CFD). The roughness created by hard fouling is one of the main drivers of hydrodynamic changes (Marty et al., 2021).
VIOLENT AND IMPULSIVE WAVE OVERTOPPING AT VERTICAL WALLS WITH LARGE FREEBOARDS
Authors: Franco Leopoldo , Bruce Tom , Cecioni Claudia , Pepi Yuri , Meer Jentsje Van der
Published: September 2023

Vertical walls are designed and built to protect coastal areas or harbours. Typically, these structures are installed in relatively deep water where incoming waves are reflected without breaking. In such cases the available prediction methods for wave overtopping discharge are well established. When the relative water depth h/Hm0 becomes smaller, waves start shoaling on the foreshore and breaking can occur leading to impulsive conditions. The present overtopping prediction methods (EurOtop, 2018) under impulsive conditions have been proposed by Van der Meer and Bruce (2014) including data from the VOWS project (Bruce et al.; 2001). Wave overtopping is strongly related to the relative freeboard Rc/Hm0, and for impulsive overtopping EurOtop suggests that for Rc/Hm0 greater than 3 there still might be significant overtopping but there is no data to validate such an extrapolation. Also the well-known overtopping graphs of Goda (2000) show that overtopping could be present for very large freeboards and impulsive waves. The objective of the present research is to investigate the mean discharge and volumes per wave from impulsive and violent overtopping at vertical walls with very large freeboards (up to Rc/Hm0 = 10).
ADAPTATION ASSESMENT OF PORT INFRASTRUCTURES FOR CLIMATE CHANGE FOR COMPOUND IMPACTS
Authors: Lara Javier L. , Lucio Alberto Fernandez, Iñigo Losada, David
Published: September 2023

Extreme events, enhanced by Climate Change may cause several damages on coastal critical infrastructures, whereas port services are even more sensible to climatic stressors than those physical assets (UNECE, 2013). Therefore, consideration of Climate Change (CC) induced variability is necessary within adaptation assessment frameworks (IPCC, 2014) that evaluate the performance of both port services and assets under the affection of diverse climatic drivers. Port infrastructure adaptation measures are assessed, focusing on critical CC-induced impacts reduction, following a probabilistic approach.
MODELLING WAVE OVERTOPPING AND WAVE IMPACTS BY MEANS OF IMAGE CLUSTERING TECHNIQUES
Authors: Formentin Sara Mizar , Dallavalle Elisa , Zanuttigh Barbara
Published: September 2023

The experimental modelling of the wave-structure interaction processes is a very complicated issue, due to the highly non-linear turbulent flow conditions, including wave breaking and air entrainment (Stringari et al., 2021). Recently, Formentin et al. (2021) demonstrated that videography can provide a reliable representation of the wave breaking, of the wave overtopping and of the wave impact at walls. They filmed laboratory tests of wave overtopping at smooth dikes with crown walls (Formentin et al., 2018; Palma et al., 2020) with a low-cost full-HD camera and compared the results of the video-cluster analysis applied to its records with the measurements obtained through traditional techniques. They derived accurate quantitative estimations of free-surface elevation, wave overtopping discharge, volumes, velocities and celerities. The aim of this paper is to further investigate the possibilities of the videography by focusing on the analysis of the wave impacts at the walls and on the detection of the amount of air entrapped during the impacts themselves.
THE DESIGN AND CONSTRUCTION OF BREAKWATER ON BAMBOO PILE FOUNDATION AT PATIMBAN PORT DEVELOPMENT PROJECT
Authors: Dong Le Phuong , Iwama Kenichi , Yamada Yoshimitsu , Takasugi Yoshikazu , Yoshizuka Naozumi
Published: September 2023

The Patimban Port Development project is stipulated in Presidential Regulation No.47 the Year 2016 as one of National Strategic Projects. The New port which is located in Subang, West Java Province, 100 km from Jakarta Metropolitan is expected to boost up the economic growth in West Java and to help improving the logistic efficiency at the Jakarta Metropolitan area where severe congestions often occurred at its sole international gateway: the Tanjung Priok Port. Among various soft soil treatments adopted in the project, bamboo pile raft (bamboo cluster of 7 piles + mattress) was adopted to strengthen the foundation for the Patimban breakwater. The use bamboo pile foundation as a soil improvement method for coastal revetment and breakwater has a long application history in Indonesia.
DESIGN OPTIONS FOR MARINE INFRASTRUCTURE IN THE FITZROY RIVER DELTA
Authors: Weerakoon Senarath , Wood Peter , Sun Michael , Zeng Weidong
Published: September 2023

This paper discusses the challenges in designing public boating infrastructure in vast tidal flood plains, including the different construction techniques used, lessons learned in design and construction and how they have been adapted in other projects. The case study focuses on two recreational public boating infrastructure projects at Inkerman Creek and Casuarina Creek, located in the flood plain delta of the Fitzroy River in the Central Queensland region.
INVESTIGATION OF SEAWATER EXCHANGE RATE FOR COASTAL PROTECTION STRUCTURES
Authors: Park JeongCheol , Sohn Jun-Hyuck , Kim Kyu-Han
Published: September 2023

Various types of coastal structures have been used as a measure to effectively block the incident high waves to control the damage behind the coast. In order to achieve the needs and specific purposes of residents, it is often constructed in a structure with strong closure, and in this case, water quality and low quality pollution may occur due to the inflow of contaminated water and congestion of seawater. In order to solve this problem, this study reviewed various kinds of countermeasures that induce seawater exchange inside and outside the facility using natural energy such as waves and tidal changes.
FRAGILITY ANALYSIS OF DUNES REINFORCED WITH GEOSYNTHETIC SAND CONTAINERS
Authors: Maggi Brian , Baxter Christopher , Grilli Annette
Published: September 2023

Encroachment of infrastructure on the natural beach system constrains dune volumes and necessitates construction of structural and nonstructural mitigation measures to improve coastal resilience. Nature-based solutions, such as dunes reinforced with geosynthetic sand containers (GSCs), are increasingly being used to stabilize coastlines and protect communities from smaller storm events (e.g. 50-year storms) while at the same time providing flexibility in design considering the uncertainty regarding rates of sea level rise and the increasing destructive power of storm events. Using risk-based hazard assessments, such as fragility curves, it is possible to quantify the resiliency of reinforced coastal systems to address these dynamic conditions. A fragility curve represents the conditional probability of failure of a coastal structure (e.g. natural dune, reinforced dune, seawall, etc.) as a function of a certain stress acting on the structure (typically water level, wave height/period; Gruhn et al. 2012). The main advantage of a fragility curve, compared to a damage function that quantifies a deterministic degree of damage directly to a stress, is that it can account for uncertainties in both the structural resistance (i.e. capacity) and the environmental stress (i.e. demand) of the system. The objective of this research is to present a fragility analysis of a U.S. Federally funded GSC-reinforced dune in Montauk, NY. This dune was constructed in 2016 and experienced significant erosion of the protective berm and sand covering the GSCs during a 1-year storm event that same year.
DEALING WITH AN EXISTENTIAL THREAT FROM CLIMATE CHANGE AT EBEYE, MARSHALL ISLANDS: STRUCTURAL PROTECTION AGAINST STORM EROSION AND WAVE OVERTOPPING
Authors: Lawless Patrick , Blumberg Gary , Blacka Matt , Flocard Francois
Published: September 2023

Located in the Pacific between Australia and Hawaii, the Republic of Marshall Islands (RMI) is one of the World’s smallest, most isolated and vulnerable nations. Ebeye, a small low-lying and densely populated island on Kwajalein Atoll (Figure 1), is at risk from coastal inundation and erosion due to swell waves and typhoons. Impacts will be magnified as sea levels rise. The key engineering performance Objectives and Level of Service (LOS) standards include design life, acceptable structural damage and wave overtopping, and time-dependent climate change effects including sea level rise and changes in typhoon intensity.
BIODIVERSITY BENEFITS OF SCALING UP MARINE ECO-ENGINEERING
Authors: Bishop Melanie , Vozzo Maria , Mayer-Pinto Mariana , Dafforn Katherine
Published: September 2023

Marine construction is a growing source of biodiversity loss in our oceans. The ecological impacts of marine constructions arise both from their destruction and degradation of natural habitats, but also their flat and often featureless surfaces, which provide little protection to marine life from predation and environmental stressors (Bulleri, Chapman 2010; Airoldi et al. 2005). The net effect is loss of native biodiversity, and spread of pest species. Marine “eco-engineering” seeks to mitigate some of these impacts by co-designing marine constructions for humans and nature (Chapman et al. 2018). Small-scale experiments indicate benefits to biodiversity of adding complex surface geometries to marine built structures (Strain et al. 2018, 2020). However, there are few examples where habitat complexity has been added to marine constructions at scale. We assessed the biodiversity benefits of adding habitat complexity to seawalls at scales of tens of meters, We also compared the efficacy of different types of habitat complexity in benefiting biodiversity.
ADVANCES IN COASTAL FLOODING AND OVERTOPPING INVESTIGATIONS USING A 3D PHASE-RESOLVING WAVE MODEL
Authors: Kistner Stephan , Luger Stephen , Walker Stewart
Published: September 2023

In engineering applications, runup and overtopping rates are often estimated from empirical parameterizations which rely on simplified assumptions of the incident wave conditions and can only be applied to a limited range of cross-shore profiles and simplified structural configurations. This study demonstrates the accuracy of DHI’s MIKE 3 Wave FM (M3WFM) model for runup and overtopping applications by comparison to physical model and prototype measurements. Subsequently the model has been used in more than six projects involving coastal flooding and overtopping investigations with applications in structural design, setback lines and response to climate change.
MULTIPHASE SPH SIMULATION FOR INCHAMBER IMPACT PRESSURE ON VERTICAL BREAKWATER WITH WAVE ABSOPTION CHAMBER
Authors: Pawitan Krisna Adi , ElDarwich Hamid , Garlock Maria M.
Published: September 2023

A numerical model of a vertical breakwater integrated with wave absorption chamber has been tested against regular wave in a virtual wave flume. The open source Smoothed-Particles Hydrodynamics, or SPH, (Lagrangian type) software called DualPSHysics was deployed for the simulation. Both the multiphase (air-water) and single-phase (water only) fluid were considered and compared with an experimental result. Single-phase and multiphase capture the water column elevation in an open chamber within a ratio of 0.92 and 0.70, respectively, when compared to experiments. However, single-phase is not able to capture the fully closed chamber effect. It is found that inside the fully closed chamber, the multiphase SPH captures the maximum (compressed) water elevation well but overestimates the air compression by a factor of 1.5.
HYDROSTATIC STABILITY EXPLORATION ON FLOATING STRUCTURES USING MACHINE LEARNING
Authors: ElDarwich Hamid S. , Garlock Krisna Adi Pawitan, Iman Mansouri, Maria M.
Published: September 2023

A hydrostatic stability analysis is an important first step in designing floating structures. Most of the currently available commercial software is limited to hydrostatic stability curves. Current research tries to address this limitation, by developing a framework which couples numerical hydrostatic stability analysis based on potential energy minimization, with a machine learning (ML) model based on genetic programming (GP). In this way, potential energy functions are efficiently obtained. The resulting analytical formulations offer a wider understanding of the hydrostatic stability of floating structures.