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Inspired by the local resonance mechanism, a resonant periodic structure (RS) constructed by an array of periodic floating oscillators is proposed for enhancing surface water wave attenuation. A hybrid frequency domain method is introduced for solving the linear or nonlinear initial-boundary value mixing problem. The numerical results show that the RS has a superior suppression effect on the propagation of waves in comparison with the Bragg periodic structure (BS) of the same scale. The incoming waves across the spectrum are substantially reduced by RS through the inverse propagation of radiation waves induced by the wave-driven oscillators. Furthermore, to achieve a better attenuation effect, a nonlinear resonant periodic structure which the periodic oscillators are integrated with the nonlinear stiffness mechanism (NSM) is proposed based on the idea of reducing equivalent stiffness. The motions of oscillators are regulated by the NSM, and the attenuation effect is further improved due to the modified radiation wave. The concept and results presented herein may provide forward-looking technical guidance for future coastal protection. [ABSTRACT FROM AUTHOR]

Vicens-Miquel, M.; Williams, D.D., and Tissot, P.E., 2024. Analysis of sandy beach morphology changes and inundation events from a high spatiotemporal resolution dataset. Journal of Coastal Research, 40(6), 1001–1018. Charlotte (North Carolina), ISSN 0749-0208. Coastal inundation creates significant beach management and conservation challenges. The frequency of these events is increasing because of the influence of sea-level rise in combination with background erosion and subsidence in some areas. More accurate predictive models are needed to anticipate potential coastal inundation events for public safety and protection of backshore infrastructure, as well as beach management that can be improved by including the influence of wave runup. Improvement of prediction accuracy requires an in-depth exploration of changes in beach morphology over time and an understanding of the complex interactions responsible for change. This study focuses on changes in beach morphology along a representative beach segment adjacent to Horace Caldwell Pier, Port Aransas, Texas. Ongoing monitoring, initiated in July 2022, provides a rich dataset for analyzing 21 beach-profile surveys, capturing the dynamic evolution of the coastal landscape. Emphasis is placed on quantifying the influence of metocean conditions, particularly high waves with varying periodicity, and wind patterns on morphologic alterations. This research identified two types of inundation events, with two of them resulting in erosion. Consequently, the findings suggest a correlation between the onset of erosion and a maximum dominant wave period of approximately 10 seconds in the study area. The findings contribute to a better understanding of the challenges inherent in predicting coastal inundation and event-based beach morphology changes, fostering informed decision-making that supports sustainable coastal management and developing effective conservation practices. [ABSTRACT FROM AUTHOR]

In alignment with the Cornwall and Isles of Scilly Shoreline Management Plan (SMP2), adopted by Cornwall Council, the Coverack North Coast Protection Scheme comprised the construction of a c. 125 m-long rock armour revetment, and 55 m-long retaining wall, at Coverack Cove on the Lizard Peninsula in Cornwall, UK. This was to prevent sea erosion impacting vehicle access via the B3294, the main public highway into Coverack. The site of the proposed works on Coverack Beach is part of a Natural England designated Site of Special Scientific Interest (SSSI) for its geology, specifically the exposure on the foreshore of an almost continuous cross-section of a palaeo-Moho, the former boundary between the Earth's crust and underlying mantle. Following a period of consultation, a set of management proposals and mitigation measures were agreed with Natural England and Cornwall Council to protect and offset the impact of the proposed works on the SSSI asset. It can be difficult to reconcile the issue of protecting communities from coastal erosion and ensuring the protection of geological assets. However, this can be mitigated if a balanced approach is adopted, and the work is sensitively managed to offset the impact of coastal protection schemes such as this. [ABSTRACT FROM AUTHOR]

The Bay of Bengal has been at the heart of human civilisation and trade for many centuries. Accordingly, this oceanic space has seen influx of people from around the world including European traders who plundered natural wealth of this region for many years. Unabated exploitation of natural resources has been the primary reason for deterioration of environment of this part of the world. To add to this, supporting a growing population through unsustainable anthropogenic activities for decades is considered a primary cause for deterioration of marine life, habitats, coastal and marine ecosystems and numerous ocean ecosystem services of this oceanic space. Since the health of the oceanic space is critical for survival of life of Earth, a detailed study of the impacts of a growing population on the coastal environment of the Bay is considered important. Unfortunately, since the anthropogenic activities causing this deterioration are numerous, they cannot be covered in one paper. Hence, only a select few critical anthropogenic activities causing coastal erosion, resource degradation, and marine pollution are being analysed here. The study shows that as a result of increasing population, terrestrial activities such as increasing built up area, industries, land use activities, fisheries and aquaculture, and construction of shore protection structures have resulted in reduced coastal vegetation and increased pollution of the ocean. As a result the coastal landscape is witnessing increased coastal erosion, coastal flooding and inundation, loss of vegetation and faunal communities especially fishes. While local initiatives and projects reflect a positive commitment to address resource degradation and to create resilient coastal ecosystems, these efforts need to be transformed into achievements by dedicated and nuanced involvement of all stakeholders, especially the public, for the desired results. [ABSTRACT FROM AUTHOR]

In the surfzone, breaking‐wave generated eddies and vortices transport material along the coast and offshore to the continental shelf, providing a pathway from land to the ocean. Here, surfzone vorticity is investigated with unique field observations obtained during a wide range of wave and bathymetric conditions on an Atlantic Ocean beach. Small spatial‐scale [O(10 m)] vorticity estimated with a 5 m diameter ring of 14 current meters deployed in ∼2 m water depth increased as the directional spread of the wave field increased. Large spatial‐scale [O(100 m)] vorticity calculated from remote sensing estimates of currents across the surfzone along 200 m of the shoreline increased as alongshore bathymetric variability (channels, bars, bumps, holes) increased. For all bathymetric conditions, large‐scale vorticity in the inner surfzone was more energetic than in the outer surfzone. Plain Language Summary: Circular, rotating flow features, such as eddies, swirls, and vortices mix and disperse material throughout the ocean. Here, circular flow features that can transport sediments, pollutants, and biota from the shore to the continental shelf were investigated using field observations from a 5 m diameter ring of current meters in 2 m depth and from tracking naturally occurring ocean foam visible in optical images of the surfzone (where waves break) spanning 200 m of the coast. The observations show that small‐scale flow patterns become more energetic as ocean waves arrive from a wider range of directions and that large‐scale flow features become more energetic as the seafloor becomes more nonuniform (including holes and channels). Key Points: Surfzone vorticity is estimated for the first time with unique field observations within, across, and along the surfzoneIn situ observations show that small‐scale vorticity injected by breaking waves increases with wave directional spreadRemotely sensed observations show large‐spatial scale vorticity increases as bathymetry becomes more alongshore inhomogeneous [ABSTRACT FROM AUTHOR]

Field observations on storm induced beach changes are important to improve our effort on beach management. This study compared storm induced beach changes caused by hurricane Hermine in 2016 (4 years after a beach nourishment) and Tropical Storm Eta in 2020 (2 years after a beach renourishment) along the barrier-island coast of west-central Florida. Pre-Eta beach were 1 to 2 times wider than that of pre-Hermine. Since Hurricane Hermine and TS Eta generated a similar hydrodynamic condition for the study site, comparing beach changes induced by these two storms provides a unique opportunity to investigate the response of different antecedent beach conditions to energetic events. The shore protection effect of beach nourishment is apparently evidenced by the fact that post-Eta shoreline was located seaward of those post-Hermine at half of the beach-profile locations in the study area. The shore protection effect in the subaerial portion of the beach, however, is not obvious for the other half of beach profiles where shoreline positions were retreated to similar locations after these two storms. Instead, their shore protection effect occurred in the sub-aqueous portion of the beach and was indicated by higher sandbar crests located closer to the shoreline, which can dissipate and reduce incoming wave energy. The shoreline elevation needs to be properly defined (Mean High Water vs Mean Low Water line) as it is used as a proxy to represent beach volume loss. For Hermine induced beach change, no significant correlation exists between MHW line change and beach volume loss. While a significant correlation exists between MHW line change and beach volume loss induced by TS Eta. This correlation pattern switched if the shoreline here is defined as mean low water line. For efficient beach/shoreline management, multiple proxies (e.g., sandbar height and location of its crest and trough) in addition to shoreline change should be used to assess the performance of beach nourishment project. [ABSTRACT FROM AUTHOR]

Further global warming is projected to increase coastal erosion. Therefore, coastal protection is being intensified with a strong emphasis placed on environmental biotechniques. One such activity is anti-erosion planting using alien plant species. The aliens penetrate from the plant species into the natural ecosystems, reducing their biodiversity and ecosystem services. Parallel to coastal protection, measures for nature conservation are undertaken to eliminate invasive aliens from the natural ecosystems that take over. Such actions are featured in the master plans drafted for the Natura 2000 sites on the south Baltic coast. Although there is no sufficient scientific evidence, Salix acutifolia willow used in anti-erosion plantings was considered a neophyte invading white and grey dune habitats and reducing their biodiversity. The master plans mandated the elimination of the willow without considering the role of its spontaneous locations in providing erosion-control services. In 2017–2023, research was undertaken on the south Baltic coast (Wolin Island) on the arguments behind such a radical conservation action. We present the results of these studies. We consider the elimination of S. acutifolia from its spontaneous locations as a reduction in both its erosion-control services and the willow's role in nature conservation. We present some principles for action in case of a conflict between coast protection and nature conservation. [ABSTRACT FROM AUTHOR]

This study proposes a novel model of a dual-purpose nonlinear wave farm, wherein multiple wave energy converters (WECs) equipped with nonlinear stiffness mechanism (NSM) are deployed for energy production and wave attenuation. A hybrid semi-analytical approach integrating the eigenfunction expansion matching method (EEMM) with the multi-harmonic balance method (MHBM) is developed to address the nonlinear wave-structure interactions among an array of WECs. Each device is modeled as a truncated cylinder, and the effects of the nonlinear interaction on power absorption and wave evolution from the array are studied. The analytical results are validated through published experimental results and computational fluid dynamics (CFD) results. A multi-parameter analysis is conducted to explore the impact of various factors including power takeoff (PTO) damping, NSM configuration, wave direction, and layout geometry on both wave power absorption and wave evolution. The results demonstrate that the nonlinear wave farm exhibits improved power-capture efficiency and enhanced wave attenuation compared to the linear wave farm, attributed to the phase control mechanism of NSM. This work may provide profound guidelines for large-scale wave energy exploitation and coast protection. [ABSTRACT FROM AUTHOR]

Maravanthe Beach has been witnessing erosion due to waves caused by tidal forces, destroying vegetation, and causing enormous damage to people's lives, livestock, and property. Hence, an attempt has been made to understand the shoreline change analysis using the automatic shoreline extraction method and determine the rate of change in terms of erosion and accretion rate before and after the construction of coastal structures during the period from 2014 to 2023. The SWAT model was applied to analyze the influence of surface runoff on shoreline changes near Maravanthe Beach for the periods 2004–2014 and 2012–2023. Also, runoff was chosen as one of the parameters for validation of the analysis. It was noticed that the shoreline stretch had experienced significant erosion prior to the construction of shore protection infrastructure. Soon after the deployment of certain shore structures, the shoreline progressed from a high erosion stretch to a low erosion stretch. This study reveals that Maravanthe Beach witnessed greater erosion during the period 2014–2018 than it did from 2019–2023 and also observed a decrease in erosion from 11% to 3% and an increase in the accretion zones from 2 to 9%. [ABSTRACT FROM AUTHOR]

The authors discuss the possibility of using combined structures consisting of blocks filled with crushed stone in hydraulic engineering construction. Tasks are set and problems of using soil-filled blocks as part of bank protection structures are identified. Then, calculations are given, and the construction of the structural elements of a slipway in Narva Bay, Primorsky Kray, is illustrated. [ABSTRACT FROM AUTHOR]

Wave energy conversion holds promise for renewable energy, but challenges like high initial costs hinder commercialization. Integrating wave-energy converters (WECs) into shore-protection structures creates dual-function structures for both electricity generation and coastal protection. Oscillating water columns (OWCs) have been well studied in the past with their simple generation mechanism and their out-of-water power take-off (PTO) system, which can minimize bio-fouling effects and maintenance costs compared to other submerged WECs. In addition, a slotted barrier allows for better circulation behind the breakwater while dissipating incoming wave energy through viscous damping. This study examines the performance of a new design which combines an OWC with a slotted breakwater. Small-scale (1:49) laboratory tests were performed with a piston-type wave generator. The performance is evaluated in terms of wave transmission, wave energy extraction, and wave loading under various wave conditions while focusing on the effects of the porosity of the slotted barrier and tide level changes. Results show that under larger waves, a decreasing wave transmission, increasing power extraction from the OWC, and energy dissipation from the slotted barrier are observed. On the other hand, under increasing wavelengths, wave transmission is observed to be constant; this is important for harbor design, which means that the breakwater is effective under a wider range of wavelengths. Porosity allows for more transmission while inducing less horizontal force on the structure. [ABSTRACT FROM AUTHOR]

Beach morphology assessment is very important for the sustainable development of beaches and the implementation of beach development activities through management plans. The present study focuses on assessing beach morphology and developing ecosystem-based conservative strategies to control beach erosion and improve beach safety along the two blue-flag certified beaches, Padubidri and Kasarkod, in Karnataka state. The bathymetry of the two beaches varies by gradient changes between the winter and monsoon seasons, and as a result, waves break at a distance of 15–25 m from the shore. The estimated seabed deposition between the winter and monsoon periods of 2020 is 10329 cu m and 59.36 cu m at the Padubidri and Kasarkod beaches, respectively. This study also provides the rate of shoreline change at two beaches along the coast for the period 2018–2022, as measured using geospatial technology and field investigation. The assessment revealed that the Kasarkod and Padubidri coasts experienced maximum erosion of 11.7% and 12.7%, respectively for five years. The projected shoreline changes under the climate change show erosion of 59.12 m on the northern side and accretion of about 16.13 m on the southern side of Kasarkod Beach, whereas on Padubidri Beach, erosion of 40 m on the central part of the beach between 2020 and 2030. The nearshore current magnitude is stronger at the coast of Padubidri than at Kasarkod during the study. The sediment movement from the Kamini River at the Hejamadi endpoint (southern part of Padubidri) shapes the Padubidri beach and causes accretion and erosion during winter and monsoon seasons respectively. However, these beaches are being protected by ecosystem-based conservative strategies such as beach vegetation and dune conservation through the Beach Environment and Aesthetics Management Services (BEAMS) program. Therefore, the assessment of beach morphology and conservation strategies provides a better beach management plan, to control beach erosion, and enhance beach stability. [ABSTRACT FROM AUTHOR]

This work examines the impact of oblique wave action on a combination of a rubble mound breakwater and a floating dock. The influence of the breakwater on safety of the floating dock is examined in various configurations. The breakwater is approximated by a submerged trapezoidal structure and the floating dock by a surface piercing rigid rectangular structure. A numerical solution is developed combining the eigenfunction expansion method and the multi-domain boundary element method while assuming linear water wave theory. Reflection and transmission coefficients along with wave forces on the dock are evaluated and analyzed over a wide parameter range. The study reveals that the sloping angle of the trapezoidal breakwater plays a vital role in dissipating the wave load on the floating dock and the case of a trapezoidal breakwater with a vertical lee side faces is also examined. The reflection and transmission of waves are found to be dominated by the floating dock parameters in the system, while the wave forces on the dock are reduced by increasing the length and breadth of the breakwater and frictional coefficient of the porous structure, respectively. The combination of two structures in different tandem configurations is proposed as an effective coastal protection system. [ABSTRACT FROM AUTHOR]

Sea‐level change threatens the U.S. East Coast. Thus, it is important to understand the underlying causes, including ocean dynamics. Most past studies emphasized links between coastal sea level and local atmospheric variability or large‐scale circulation and climate, but possible relationships with local ocean currents over the shelf and slope remain largely unexplored. Here we use 7 years of in situ velocity and sea‐level data to quantify the relationship between northeastern U.S. coastal sea level and variable Shelfbreak Jet transport south of Nantucket Island. At timescales of 1–15 days, southern New England coastal sea level and transport vary in anti‐phase, with magnitude‐squared coherences of ∼0.5 and admittance amplitudes of ∼0.3 m Sv−1. These results are consistent with a dominant geostrophic balance between along‐shelf transport and coastal sea level, corroborating a hypothesis made decades ago that was not tested due to the lack of transport data. Plain Language Summary: Sea‐level rise is an imminent threat to coastal communities worldwide, including the U.S. East Coast. Therefore, it is crucial to understand the processes driving regional sea‐level change. While past studies documented how coastal sea level may be influenced by large‐scale ocean circulation, less attention has been paid to the role of more local currents over the shelf and slope. Here we explore the relationship between coastal sea level along the northeastern U.S. and the Shelfbreak Jet, a current that flows along the shelfbreak from the Labrador Sea to Cape Hatteras (North Carolina). From 7 years of in situ data of both current velocities and water levels, we see that as coastal sea level rises, Shelfbreak Jet transport increases westward (and vice versa) on timescales of days to weeks. Our results lay the groundwork for understanding relationships between coastal sea level and local ocean dynamics elsewhere. Key Points: Daily Shelfbreak Jet transports and Southern New England coastal sea levels are anti‐correlated during 2014–2022The observed relationship between these two variables is consistent with geostrophic balanceFor this region, coastal sea levels are more sensitive to local ocean dynamics than to large‐scale circulation [ABSTRACT FROM AUTHOR]

Conducting long-term conservation and monitoring activities for sea turtles provides a more precise depiction of their population status compared to studies conducted across a single year. The frequency of the nesting activity may fluctuate dramatically over time, depending on the environmental conditions. This study aimed to examine the nest count, female abundance, and reproductive output of green turtles on Yeniyurt Beach in the eastern Mediterranean between 2017 and 2022. The beach was surveyed via annual monitoring at consistent intervals. Temporal variations in the nest count and abundance of females were analyzed using the Mann-Kendall and Sen's Slope tests. A total of 803 nests were recorded, with an average of 133 nests per nesting season and an average nest density of 33.5 km-1. A total of 326 nests were excavated, with 28,546 of the 36,394 eggs successfully hatched (78% hatching success). The nest count and female abundance exhibited an insignificant, monotonic upward trend. The average nesting female count per nesting season was estimated to be 138.5 based on the observed clutch frequency (CF) and 67 based on the estimated CF. Yeniyurt Beach has a high nesting activity rate, representing 6% of the Mediterranean in terms of the nest count and 5% in terms of female abundance. Approximately 12% of nests did not produce hatchlings due to flooding and predation. Yeniyurt Beach lacks a conservation status, making it vulnerable to future threats like industrialization. In addition to the designation of the area as a protected site, the rehabilitation of the backshore habitat is of significant importance. [ABSTRACT FROM AUTHOR]

Brett, J.; Samuell, M.; Augstein, B.; Parra, S.; Hancock, E.; Saunders, C.; Wunsch, S.; Winstead, N., and Boothby, J., 2024. Nature-based coastal protection: Measuring and modeling flow reduction by oysters. Journal of Coastal Research, 40(4), 647–660. Charlotte (North Carolina), ISSN 0749-0208. Natural coastal infrastructure protects coast lines from climate hazard impacts, such as erosion and flooding. Laboratory and modeling studies presented here examine the utility of oyster reefs as a form of natural coastal protection. Oyster reefs are known to provide both water quality improvements and erosion protection. Experiments were conducted to determine the effects of oysters on flow parameters in a recirculating flow channel. A cage of eastern oysters, Crassostrea virginica, was placed in the flow channel, blocking a portion of the flow, to imitate cultured oysters in the ocean. Particle image velocimetry was used to measure the flow behind the oyster cage to examine the impact of the oysters compared with a control test with an empty cage. Average velocities were reduced by 15%, with velocities directly behind the cage reduced 70% in fresh water and reversed in salt water. A setup similar to the laboratory experiments was simulated in a Coupled Ocean–Atmospheric–Wave–Sediment Transport (COAWST) model. In the COAWST model, the oyster reef was simulated as stiff vegetation with a drag coefficient of 8, reproducing the 70% reduction measured in the lab experiments. Finally, a regional model is presented, which demonstrates the impact of an oyster reef on waves and currents at a larger scale with a drag coefficient of 1.5, the highest numerically stable value found. Within the oyster vegetation patch, depth-averaged currents were reduced 14% and bottom currents were reduced 97%. Significant wave heights were reduced by 62% above the reef and 23% shoreward of the reef. The results here suggest that regional modeling such as COAWST can be an effective tool for assessing the impact of potential coastal resilience strategies to mitigate climate hazard impacts in a climate-changed world. [ABSTRACT FROM AUTHOR]

Global climate change increases storm frequency and Sea Level Rise (SLR). This leads to an increased risk of coastal flooding, reduced effectiveness of protective structures, and intensified coastal erosion and retreat. The Bona and Ceinturon beaches, two beautiful sandy beaches with low-lying topography along the eastern branch of the Giens double tombolo on the western coast of Hyères Bay, have high tourist value. These areas are very vulnerable to SLR, which is believed to reduce the effectiveness of the shore protection structures built on these sandy beaches. The effects of SLR on changes in the hydrodynamic characteristics of these water bodies need to be quantified. This may help clarify the relationship between SLR and coastal erosion. This study investigated the variation of wave height and current speed due to SLR at the Bona and Ceinturon beaches using a coupled numerical model. The performance of this model was calibrated by comparing the model results with the in situ measured data. The research results are the basis for assessing the impact of SLR due to climate change on this area and provide a useful solution for coastal management in the future. [ABSTRACT FROM AUTHOR]

Puducherry, a Union Territory of India, has been strongly affected by severe erosion after the construction of the Puducherry port in 1989. To mitigate this cause, the National Institute of Ocean Technology, Chennai, and the Puducherry government implemented a beach restoration strategy involving a hybrid solution in 2017 for coastal protection/stabilization and the restoration of the lost beach. The strategy involved deploying a steel reef into the nearshore sea and implementing beach nourishment processes. To monitor the coastal morphological changes after implementing the coastal protection strategy, the Digital Shoreline Analysis System, was adopted to calculate the rate of shoreline change statistics for the years 2016 to 2022. It uses spatio-temporal shoreline positions from multi-temporal satellite imagery. The shorelines are extracted from the Sentinel-2A satellite images by a Normalized Differential Water Index based semi-automated model. Statistical parameters in DSAS analyze the shorelines to determine the shoreline changes in this area. The results reveal the remarkable resilience of a newly restored beach, where the linear regression rate statistics in Zone A show an average accretional rate of 2.92m/yr. Alternatively, Zone B exhibits an average erosion rate of -0.23m/yr, with intermittent sandy beaches experiencing maximum erosion rates of -1.63m/yr. The influence of longshore current direction and sediment transport on shoreline movement is evident in seasonal analysis, with shoreline development and recession primarily observed near shore protection structures. The study’s outcome provides valuable insights for coastal management, offering a reliable approach for shoreline monitoring postimplementation of mitigation projects [ABSTRACT FROM AUTHOR]

Limited research has been directed toward coastal protection infrastructure compared to other types of infrastructure, despite the increasing global population in low-elevated coastal regions and the threats posed by climate change. This paper presents a risk-based asset management framework for coastal protection structures that improves accuracy with each inspection. The framework consists of five components: the Coastal Asset Inventory (CAI), Inspection and Condition Assessment (ICA) module, Backward Markovian Deterioration Model (BMDM), Forward Markovian Deterioration Model (FMDM), and Intervention Policy Engine (IPE). The framework addresses challenges in accurately predicting coastal structure deterioration due to uncertainties in wave loading conditions and the need for frequent inspections. It is applied to rubble-mound breakwaters in Alexandria, Egypt. The BMDM and FMDM models are developed based on inspection data, and the IPE optimizes interventions considering structural condition, risk thresholds, and budget constraints. Results showed that long-term deterioration estimates occur at an accelerated rate with an increase in inspection points, triggering earlier interventions. However, the framework proves reliable even with only two inspection points, allowing asset managing agencies to implement the model based on the structural condition at the year of construction and a minimum of two inspections. The proposed risk-based asset management framework provided a comprehensive approach to managing coastal protection infrastructure, reducing risks to life and property. By accurately predicting deterioration and optimizing intervention decisions, the framework can greatly assist in the effective management and maintenance of coastal assets. This is vital in ensuring the safety of coastal populations facing global climate change and demographic growth. Coastal protection structures are crucial for safeguarding coastal populations in the face of climate change and demographic growth. This research paper introduces a risk-based asset management framework for coastal protection structures, with practical applications for coastal management agencies and practitioners. The framework addresses the challenges of predicting coastal structure deterioration and optimizing intervention decisions. The framework consists of five components: the Coastal Asset Inventory (CAI), Inspection and Condition Assessment (ICA), Backward Markovian Deterioration Model (BMDM), Forward Markovian Deterioration Model (FMDM), and Intervention Policy Engine (IPE). It has been successfully applied to rubble-mound breakwaters in Alexandria, Egypt. The practical implications are significant: The framework enables asset managers to make informed decisions on coastal infrastructure maintenance and interventions, reducing risks to life and property. It provides a comprehensive approach to managing coastal protection infrastructure and ensuring the safety of coastal populations. By accurately predicting deterioration and optimizing interventions, the framework supports effective management and maintenance of coastal assets. Its reliability and flexibility make it a valuable tool for coastal management practitioners, promoting sustainable development and safeguarding coastal areas. With its potential for broader application, this risk-based asset management framework offers practical solutions for coastal protection worldwide. [ABSTRACT FROM AUTHOR]

The morphology of coastal regions is continually changing because of both natural and human factors. Monitoring and understanding these changes are essential for efficient coastal management and sustainable development. To protect and develop beaches, quantitative monitoring of coastal changes is crucial. According to this study, there is a persistent erosion issue with the shoreline of the Rosetta region in Egypt. Over the previous century, there has been noticeable erosion. This is mostly because of the Aswan High Dam, which was built in 1964 and decreased runoff and sediment flow. Five Landsat images spanning the years 1980–2023 were utilized in this study. The Nile Delta would be eroding at an alarming rate if action were not taken due to coastal erosion, which is made worse by sea level rise. Our study's primary goal is to evaluate the shoreline of the Rosetta region and identify rates of erosion and accretion as well as patterns of accumulation and erosion using a combination of statistical analysis of the coastline using DSAS software and remote sensing techniques. It also seeks to pinpoint hotspots that require security. In this study, the Shoreline Linear Regression Rate (LRR), End Point Rate (EPR), Shoreline Change Envelope (SCE), and Net Shoreline Movement (NSM) were determined by creating crosssections perpendicular to the baseline using the Digital Shoreline Analysis System (DSAS). According to the analysis of coastal change, the periods with the highest levels of erosion were between 1980 and 1990, before the protection of the promontory took place. In addition, the results extracted from this study showed a stabilized shoreline between 2000 and 2023 at the Rosetta Promontory and noticeable erosion in the east and west of the promontory. [ABSTRACT FROM AUTHOR]

This paper explores the application of Deep Reinforcement Learning (DRL) and Sim2Real strategies to enhance the autonomy of beach-cleaning robots. Experiments demonstrate that DRL agents, initially refined in simulations, effectively transfer their navigation skills to real-world scenarios, achieving precise and efficient operation in complex natural environments. This method provides a scalable and effective solution for beach conservation, establishing a significant precedent for the use of autonomous robots in environmental management. The key advancements include the ability of robots to adhere to predefined routes and dynamically avoid obstacles. Additionally, a newly developed platform validates the Sim2Real strategy, proving its capability to bridge the gap between simulated training and practical application, thus offering a robust methodology for addressing real-life environmental challenges. [ABSTRACT FROM AUTHOR]

Coastal protection structures reduce risks and economic losses by eliminating coastal erosion, wave damage, and flooding. Fixed breakwaters are used along the coast but are often inappropriate due to their negative environmental impact. Permeable breakwaters resemble a row of breakwaters with continuous walls and are proposed as a more environmentally friendly alternative. The wave-structure interaction and flow behavior of this type of breakwater are more complex but must be analyzed before designing it. This study develops a mathematical model of wave interaction with a permeable three-row vertical breakwater based on the least squares method. Comparison with experimental measurements of the reflection, transmission, and dissipation coefficients shows that the mathematical model adequately reproduces most of the important features of the results. This study provides a deeper understanding of the hydrodynamic performance of a permeable three-row vertical continuous wall breakwater. [ABSTRACT FROM AUTHOR]

Chennai has had the longest coastline over other major cities of India. It is decidedly vital to monitor seawater quality due to the increased coastline population. This study presents an Android mobile application based on a machine learning approach to perform basic testing parameters of seawater by applying convolutional neural network concepts. A commercially available "saltwater master test kit" was used in this study to test the level of pH, Ammonia, Nitrite, Nitrate, and Total Phosphate (T.P.) in seawater. Six water samples collected from every 10 regions, including the coastline and coastal estuaries, were tested with the test kit in a microplate. Images were captured in the solely designed mobile app, and they were pre‐processed, and RGB (Red, Green, and Blue) were recorded from the Region of Interest (R.O.I.) of the image. A supervised Convolutional Neural Network Image Classifier (SCNNIC) algorithm was developed to classify the RGB pixel values. CIEDE2000 (C2K) color difference algorithm was applied over the recorded RGB values with the datasets stored previously to result in the nearest color match between the ideal dataset and R.O.I. of the captured image. Grayscale and RGB methods results were compared with the standard APHA method. This C2K color difference algorithm produced a percent accuracy of over 98% compared with other methods used, and R2 recorded by curve fitting method for pH, T.N. and T.P. were above 0.98. Disquieting results were reported in this study, especially in Muttukkadu backwater and Adayar river backwater estuaries, reported high values of pH (7.82 and 8.17), TN (13.74 mg/L and 13.45 mg/L) and T.P. (0.266 μg/L and 0.724 μg/L). The mean for all 10 regions of 110 km chosen in this study for the 2 years was calculated, and values were obtained as pH‐8.33, TN‐5.321 mg/L, and TP‐0.143 μg/L. [ABSTRACT FROM AUTHOR]

Coastal erosion and the need for flood protection present globally significant challenges. To address these challenges, hard coastal protection structures, such as groynes, are employed worldwide to safeguard coastal areas and regulate currents. However, their specific effects on current dynamics and sediment properties, particularly within tidal inlets, remain inadequately investigated, especially in regions like the North Sea characterized by prevalent tidal currents. This study aims to address the knowledge gap by examining the long-term impacts of coastal protection measures on sedimentology, with a focus on the environment of a tidal inlet. The Southern North Sea coast is subject to mesotidal conditions. It presents a mixed-energy coast with an erosive eastward littoral drift, providing an ideal setting for this investigation. On the island of Wangerooge, a prominent groyne extends into the Harle inlet, significantly restricting the exchange area between the North Sea and the Wadden Sea. Consequently, the changes in flow dynamics and sediment transport resulting from the construction significantly affect sediment distribution and morphology within the inlet. Sedimentological analysis was employed to characterize surface sediment properties and statistical analysis identified seven distinct facies associated with three realms, which were shaped by the tidal currents affected by the groyne to a distinct pattern. Additionally, the integration of multibeam data from existing literature facilitated the creation of a comprehensive facies map. These findings suggest alterations in the morphology of the inlet. By comparing the results with an unaffected inlet, the Otzumer Balje, this study provides valuable insights into the complex interplay between coastal protection infrastructure and coastal sedimentology within a high-dynamic tidal inlet system. [ABSTRACT FROM AUTHOR]

Bluff landforms, sought-after for housing and development, present a hazard management challenge due to erosional processes despite the perceived safety of elevated land. This study focuses on the Neuse River Estuary in North Carolina, exploring coastal risk perception and erosion. A survey protocol was developed, and questionnaires targeted 246 residents with property within 100 m of the shoreline and 54 land use professionals in Craven County. To explore the connection of individual experiences with erosion, we use openly accessible LiDAR to quantify bluff retreat and erosion between 2014 and 2020, a period that encompasses Hurricane Florence in 2018. Our findings show: 1) survey results reveal a consensus among residents, with 90% observing alterations attributed to storm impacts, 2) preferences for addressing erosion lean towards structural measures, aligning with existing protection strategies (e.g., bulkheads, rip-rap) as opposed to nature-based solutions, 3) bluff tops are eroding at a higher median rate of -0.59 m per year, compared to -0.19 m per year for high sediment banks, and 4) an overall net volume decrease of approximately -1.89 cubic meters per year for Craven County, slightly more than the overall net loss for the Neuse River Estuary, which was -1.74 cubic meters per year. The findings underscore the need for a cohesive bluff erosion management plan, emphasizing the complexity of challenges and the importance of a holistic approach that combines technical studies with effective risk communication. [ABSTRACT FROM AUTHOR]

Sharks and rays are animals that human activities have gradually impacted. One of the activities significantly affecting this group of fish is indiscriminate fishing, as a result of incipient environmental monitoring and enforcement, the use of common names for a variety of distinct species, and the processing of animals (e.g., decapitation) still onboard, making their identification difficult. Additionally, elasmobranchs have complex biological and reproductive characteristics that make them vulnerable to human activities and overfishing, such as a long-life cycle, late sexual maturity, and low fecundity. In this context, our premises suggest that the effective conservation of elasmobranchs involves the society as a whole and should be successful in adequately monitoring vulnerable and endangered species. Therefore, the project ‘Conservação da Biodiversidade: Tubarões na Praia’ (Biodiversity Conservation: Sharks on the Beach) aimed to integrate the Federal University of Paraíba (UFPB) and society to disseminate knowledge related to the diversity of elasmobranch species off the coast of Paraíba state, Brazil, their biological aspects, and levels of vulnerability, ultimately promoting their conservation. Our Instagram page reached approximately 1,500 followers, with individual posts averaging 150 likes and reaching around 600 accounts. The public engagement was significant, fostering not only knowledge exchange but also a new perception and heightened interest in the group. [ABSTRACT FROM AUTHOR]

The cross‐shore transformation of breaking‐wave roller momentum and energy on observed barred surfzone bathymetry is investigated with a two‐phase Reynolds Averaged Navier Stokes model driven with measured incident waves. Modeled wave spectra, wave heights, and wave‐driven increases in the mean water level (setup) agree well with field observations along transects extending from 5‐m water depth to the shoreline. Consistent with prior results the roller forcing contributes 50%–60% to the setup, whereas the advective terms contribute ∼20%, with the contribution of bottom stress largest (up to 20%) for shallow sandbar crest depths. The model simulations suggest that an energy‐flux balance between wave dissipation, roller energy, and roller dissipation is accurate. However, as little as 70% of the modeled wave energy ultimately dissipated by breaking was first transferred from the wave to the roller. Furthermore, of the energy transferred to the roller, 15%–25% is dissipated by turbulence in the water column below the roller, with the majority of energy dissipated in the aerated region or near the roller‐surface interface. The contributions of turbulence to the momentum balance are sensitive to the parameterized turbulent anisotropy, which observations suggest increases with increasing turbulence intensity. Here, modeled turbulent kinetic energy dissipation decreases with increasing depth of the sandbar crest, possibly reflecting a change from plunging (on the steeper offshore slope of the bar) to spilling breakers (over the flatter bar crest and trough). Thus, using a variable roller front slope in the roller‐wave energy flux balance may account for these variations in breaker type. Plain Language Summary: As ocean waves break in shallow water near the shore, they generate a "roller," the foamy white bubble‐laden air‐water mixture at the top of the breaking wave. The water in the roller carries energy and momentum onshore, which affects the magnitude of flows and water level changes caused by breaking waves. Here, the roller evolution is investigated with a numerical model that includes the breaking‐wave air and water mixture. The model simulates breaking waves and water levels observed near a sandbar, and shows that the roller transports momentum shoreward and damps wave energy. In addition, the results suggest that the depth of water over the sandbar may affect the shape of the breaking waves, with the roller relatively more important when water is deeper. Other mechanisms, such as turbulence in the water column, friction from the seabed, and the inertia of currents may affect how momentum is distributed in the system. Key Points: A two‐phase RANS model accurately simulates random wave transformation and wave‐driven setup observed on barred ocean beaches15–25% of the wave energy transferred to the roller is dissipated in the water column below and the rest is dissipated within the rollerThe simulations suggest that using a variable roller front slope in roller parameterizations may account for differences in breaker type [ABSTRACT FROM AUTHOR]

This article provides an overview of the evaluation of the Gross Ecosystem Product (GEP) in the Changdao sea area in China from 2017 to 2019. The GEP represents the total monetary value of ecosystem products used by people within a specific administrative jurisdiction. The study found that the GEP in the area experienced a slight overall decrease of 5.64% during the three-year period, with the values of regulating and cultural products decreasing. The study emphasizes the importance of incorporating ecological benefits into performance evaluations and suggests areas for future research and improvement in evaluation methods. The article also references scientific articles related to ecosystem services and the quantification of natural capital, providing valuable information for researchers interested in the relationship between ecosystems and economic policy. [Extracted from the article]

Mangrove forests reduce wave attack along tropical and sub-tropical coastlines, decreasing the wave loads acting on coastal protection structures. Mangrove belts seaward of embankments can therefore lower their required height and decrease their slope protection thickness. Wave reduction by mangroves depends on tree frontal surface area and stability against storms, but both aspects are often oversimplified or neglected in coastal protection designs. Here we present a framework to evaluate how mangrove belts influence embankment designs, including mangrove growth over time and failure by overturning and trunk breakage. This methodology is applied to Sonneratia apetala mangroves seaward of embankments in Bangladesh, considering forest widths between 10 and 1000 m (cross-shore). For water depths of 5 m, wave reduction by mangrove forests narrower than 1 km mostly affects the slope protection and the bank erodibility, whereas the required embankment height is less influenced by mangroves. Sonneratia apetala trees experience a relative maximum in wave attenuation capacity at 10 years age, due to their large submerged canopy area. Once trees are more than 20 years old, their canopy is emergent, and most wave attenuation is caused by trunk and roots. Canopy emergence exposes mangroves to wind loads, which are much larger than wave loads, and can cause tree failure during cyclones. These results stress the importance of including tree surface area and stability models when predicting coastal protection by mangroves. [ABSTRACT FROM AUTHOR]

Human-induced shoreline instability is a widespread issue among the world's Mega Deltas. Out of 120 million tons/year of sediment, 30 million tons/year reached Damietta promontory before the entire operation of Aswan High Dam (AHD), which blocks most of that sediment. This study uses remote sensing techniques to investigate the Land Use Land Cover Changes (LULCC) and the shoreline dynamics around Damietta promontory. In addition, more attention was devoted to the challenges of Damietta Harbour, which regularly suffers from inlet closure using a filed validated morpho-dynamic model addressing sediment transport and erosion problem at the eastern part. The LULCC based Maximum Likelihood approach shows that the developed areas were doubled from 1984 to 2018. Besides, within the Area of Interest (AoI), 8.961 km2 were eroded during the period (1984–2000), while 2.7046 km2 were eroded during (2000–2018). Change detection technique showed that accretion area was 1.8991 and 2.4909 km2 for the periods 1984–2000 and 2000–2018, respectively. Six scenarios were tested to investigate the best combinations of interventions to mitigate the challenge of siltation inside the harbour entrance and the erosion at the eastern side. Morphodynamical results showed that scenario 4 (two groins each 1000 m length at the west side of the western jetty combined with two groins each 500 m length at the east side of the existing eastern jetty of the harbour) has considered the best scenario. [ABSTRACT FROM AUTHOR]

This paper digs deeper into the phenomenon of wave oscillation that is caused by external forces, such as air pressure and seismic vibrations. This would eventually lead to potentially dire consequences, particularly in coastal areas. In order to solve this issue, this study focuses on adding a rigid breakwater at the bottom of the basin to minimize the aforementioned damages. We will be looking at a semi-closed basin with triangular width and either constant or triangular depth, to which is added one block of the submerged breakwater with smooth and rough surfaces. We will employ the modified shallow water equations to obtain the analytical natural period for each basin type. After that, numerical simulations are carried out to check the presence of resonance phenomena in each basin. Additionally, the study investigates the crucial role of the friction coefficient in preventing resonance in basins with rough-surfaced submerged breakwaters. The aim is to explore whether a single block of smooth-surfaced submerged breakwater is sufficient to eliminate resonance or whether other conditions are necessary to halt the resonance phenomenon in each basin. Ultimately, the findings of this study hold potential benefits for individuals involved in the planning and construction of harbors and protective structures. By gaining a deeper understanding of wave oscillation and resonance in semi-closed basins, the research aims to contribute valuable insights for creating more effective and resilient coastal protection measures. [ABSTRACT FROM AUTHOR]

Huang, W.; Li, S.; Lu, Y., and Zhang, R., 2024. Hydrodynamic characteristics of an ecological revetment cavity structure under the propagation of ship-generated waves in a restricted channel. Journal of Coastal Research, 40(2), 382–394. Charlotte (North Carolina), ISSN 0749-0208. With the rapid development of inland waterway transportation and the rapid increase of ship traffic in restricted channels, the role of ship-generated waves on the restricted channel shore slope becomes increasingly significant. Some river bank protection projects use cavity structures to prevent bank slopes from being scoured and have achieved remarkable results. However, the hydrodynamic characteristics under the action of ship traveling waves inside and outside the cavity are not yet clear. Thus, this paper studies the time and frequency domain characteristics of ship-generated wave fluctuations, flow velocity distribution characteristics, and turbulence distribution characteristics in the cavity, under the action of ship-generated waves, by conducting self-propelled ship model flume tests using a new type of cavity shore protection structure applied to a restricted channel. This study investigates the application of such a structure to shallow water coastal areas with frequent ship traffic. The corresponding results demonstrate that during the ship traveling wave transfer to the cavity, the fluctuation frequency did not change significantly, and fluctuation energy concentrated in the frequency range of 0–1.5 Hz. The high-frequency (0.40–1.5 Hz) energy is concentrated in the secondary wave process, and the low-frequency (0–0.40 Hz) energy is observed throughout the fluctuation process. The cavity structure changes the flow velocity from low-frequency periodic flow to high-frequency oscillatory flow, and the frequency of flow velocity change tends to be uniformly distributed with significantly enhanced turbulence. The cavity's maximum wave height, flow velocity, and turbulence energy positively correlate with the self-propelled velocity of the vessel Vc. Moreover, the characteristic values increase slowly for Vc in the subcritical velocity region (Frh < 0.84), and the characteristic values increase sharply for Vc in the transcritical velocity region (0.84 < Frh < 1.12). [ABSTRACT FROM AUTHOR]

Damaging and accelerated anthropization in coastal areas, as well as the need to adapt to climate change, means we must concentrate on improving management plans based on the diagnoses provided by coastal studies. Among these studies is the vulnerability assessment, obtained from evaluating a set of variables or indicators, which contribute to sustainable development. Since there is no single list of variables to consider in determining coastal vulnerability, 60 vulnerability studies from a period of 29 years (1994–2023), from across the globe, were consulted, and through a statistical mode method, the variables most used by multidisciplinary authors were identified. These studies were organized into groups: ecological, geomorphological, maritime climate, socioeconomic and legislative; creating sets categorized as the minimum indispensable, acceptable, and ideal variables. The results showed that most studies use between six and seven variables from only the maritime climate and geomorphological information groups. The number of variables used by individual studies, on the other hand, was not directly related to the scales (global, national, regional, local), but to the risks, such as flooding and erosion, it resolved. Only two studies included the minimum essential information for the legislative group, which is the presence of protected natural areas. Coastline displacements was the variable most used (43 studies), followed by the geoform type and the rate of sea level change (36), the wave regime (35) and the tidal range (33). The DSSs (Decision Support Systems) for coastal management were also reviewed, showing that these systems focus on a topic with a greater number of variables. [ABSTRACT FROM AUTHOR]

The dams and banks of small water reservoirs face significant erosion from wind-generated oscillatory waves. Proper design of structure height is crucial to protect such banks against erosion, considering the maximum characteristics of wind waves. Long-term measurements at the Hulín reservoir revealed that the wave spectrum aligns best with the Bretschneider type. This spectrum serves as a basis for simulating oscillatory waves and their impact on shore protection structure design. Empirical models were evaluated using wind and wave data from Hulín reservoir in the Czech Republic. The measured wind speeds attained a maximum of 8 m/s, and wave heights reached up to 15 cm. The Bretschneider (SMB) empirical formula provided the most accurate estimation of wave height (Hm0), with an average underestimate of RMSE = 0.038 m. On the other hand, Wilson revisited (WIL rev.) performed less effectively, with an average RMSE = 0.304 m. For wave period (T) estimation, Bretschneider (SMB) yielded the best results, with an average RMSE = 0.062 s. Conversely, Wilson revisited (WIL rev.) showed poorer performance, with an average underestimate of RMSE = 2.196 s. The discrepancy between the empirical formulas and measured values, particularly in underestimating Hm0, can be attributed to inaccurate determination of fetch length and wind speed. [ABSTRACT FROM AUTHOR]

The article discusses the advancements in sediment assessment, management, and regulation in the 21st century. It highlights the evolution of the definition of sediment quality, which now includes more than just toxicity and considers the chemical and physical characteristics of sediment that contribute to the health of aquatic ecosystems. The article also mentions the advances in sediment sampling methods and the development of new tools and methodologies for analyzing and interpreting sediment risk. It emphasizes the importance of understanding the role of sediments in supporting various ecosystem services and the need for sustainable sediment management strategies. The article concludes by calling for a reexamination of the scientific principles and tools used in sediment assessment and management to ensure the long-term protection of aquatic ecosystems. [Extracted from the article]

Wind wave observations in shallow coastal waters are essential for calibrating, validating, and improving numerical wave models to predict sediment transport, shoreline change, and coastal hazards such as beach erosion and oceanic inundation. Although ocean buoys and satellites provide near-global coverage of deep-water wave conditions, shallow-water wave observations remain sparse and often inaccessible. Nearshore wave conditions may vary considerably alongshore due to coastline orientation and shape, bathymetry and islands. We present a growing dataset of in-situ wave buoy observations from shallow waters (<35 m) in southeast Australia that comprises over 7,000 days of measurements at 20 locations. The moored buoys measured wave conditions continuously for several months to multiple years, capturing ambient and storm conditions in diverse settings, including coastal hazard risk sites. The dataset includes tabulated time series of spectral and time-domain parameters describing wave height, period and direction at half-hourly temporal resolution. Buoy displacement and wave spectra data are also available for advanced applications. Summary plots and tables describing wave conditions measured at each location are provided. [ABSTRACT FROM AUTHOR]

The nonlinear Schrödinger equation is used to model various phenomena, such as solitons self-focusing effects and rogue waves. In the ocean engineering, the modified nonlinear Schrödinger equation investigates the behavior of water waves, considering the complex interaction of dispersion nonlinearity, and dissipation effects. By introducing fractional derivatives to the model, the M-fractional conformable modified nonlinear Schrödinger equation allows for the investigation of fractional order effects, which can study more accurately the behavior of wave propagation in real-world ocean engineering. The novelty of our research lies in the application of of the M-fractional conformable derivative on the governed equation which represents an advancement in the existing work, which have used nonlinear Schrödinger equations without fractional derivatives. Two powerful techniques: the Jacobi elliptic function method and unified solver method are applied to attain solutions to the M-fractional modified nonlinear Schrödinger equation. The several results, including dark, bright, singular, periodic, and dark-bright soliton solutions are obtained which provide valuable insights into the complex behavior of water waves in ocean engineering. Additionally, 3D and contour graphs have been provided to visually illustrate the impact of the fractional order. We also illustrate these solutions at different values of the fractional order which explain how variations in this parameter affect wave propagation. These findings will contribute to the advancement of ocean engineering techniques, enhancing our ability to design and implement effective solutions for coastal protection, offshore structures, and marine renewable energy systems. [ABSTRACT FROM AUTHOR]

Coastal erosion is a global concern that has been augmenting due to the natural evolution of beaches, human activities and sea-level rise. One of the eco-friendly shore protection methods is to dissipate the wave energy by constructing offshore breakwaters. Conical pile head breakwater (CPHB) is one of the eco-friendly innovative offshore structures consisting of closely spaced piles with an enlarged cross-sectional area (conical pile head) in the vicinity of the free surface. In the present study, perforations are incorporated over the conical pile head to achieve higher efficiency by promoting energy dissipation. The influence of the perforations on the performance characteristics, namely wave transmission (Kt), wave reflection (Kr) and energy dissipation (Kd) of the perforated CPHB is comprehensively investigated through physical model studies. The effect of perforations and their distribution around the pile head (Pa), percentage of perforation (P) and size of perforations (S/D) on the wave attenuation characteristics are evaluated to arrive at an optimum configuration. The study is carried out under monochromatic waves of varying wave height (0.06–0.16 m) and wave period (1.4–2 s) at different depths of water (0.35, 0.40 and 0.45 m). A minimum Kt of 0.58 associated with Kr of 0.26 and Kd of 0.78 is obtained with an optimum configuration of Pa = 50%, P = 19.2% and S/D = 0.25. The Kt of the proposed CPHB is about 19 to 35% lesser than that of the perforated hollow pile breakwater under matching test conditions. Overall, providing the perforations is found to be effective in enhancing the wave attenuation capability by up to 12.4%. Further, empirical equations are formulated and validated with the experimental data. The empirical equations estimate the Kt and Kr values accurately with a high coefficient of determination (R 2 ≥ 0.90). [ABSTRACT FROM AUTHOR]

Here, the presence or absence of territoriality was evaluated in an all-male Nile crocodile (Crocodylus niloticus) group living in an ex-situ environment. Location data for each crocodile within the exhibit were collected three times per day over a two-year period, including two warm seasons and two cold seasons. A geographic information system (GIS) was used to create seasonal home ranges and core areas for each crocodile, to quantify the overlap of these home ranges and core areas to assess potential territoriality, and to calculate exhibit preferences of the group. Core area overlap was significantly lower than home range overlap, suggesting the crocodiles established territories within their exhibit. This pattern of behavior was similar across seasons, though it moderately intensified during the cold season. The crocodiles appeared to be more territorial in water, as overlap was most concentrated on the central beach, the only feature utilized more than expected based in its availability in the exhibit. These findings highlight the behavioral complexity of Nile crocodiles in human care, specifically the ability of Nile crocodiles to adapt to ex-situ environments similar to their wild counterparts by forming territories despite spatial constraints. Identifying the presence of territorial behavior is important for the care and welfare of ex-situ animals, as territorial animals have specific requirements that may result in increased agonism when unmet. It can also provide valuable context to aid in mitigation strategies, for example, when undesirable levels of agonism do occur. The findings here provide an example of how methodology from the wildlife ecology field can be adapted to ex-situ settings using a GIS and contributes to the current understanding of crocodilian behavior in human care. [ABSTRACT FROM AUTHOR]

Pulau Baai Port, located strategically in the Indian Ocean and considered a vital maritime hub in Indonesia, grapples with persistent challenges related to abrasion and sedimentation, which negatively impact its maritime infrastructure. One of the affected components is the exposed gas pipeline installation along the port's coastline. The sedimentation rate along Pulau Baai's coastline is alarming, ranging from 600,000 to 800,000 m3/year, resulting in coastal abrasion at a rate of up to 20 m/year. This study focuses on three scenarios using MIKE 21, including a baseline without alternatives, shore protection alternatives, and jetty protection alternatives. A comprehensive dataset, incorporating bathymetric maps, wave patterns, current data, and sediment characteristics, supports the analysis of coastal dynamics, emphasizing the urgency for intervention. The research introduces the novelty of analyzing coastal abrasion through the exposure of underground pipelines, establishing a relationship between impacting factors such as wave height, tides, sedimentation, and coastal abrasion. Mitigation alternatives, particularly alternative model-2 with jetty protection, are recommended based on a thorough evaluation of the model performance and actual measurements. The results show that Pulau Baai's sediment, primarily sandy, experiences substantial abrasion and coastline changes, notably in alternatives-2 and -3. The study anticipates potential sedimentation in certain sections of the subsea exposed pipelines in the absence of shore protection. The outcomes of this research provide a foundational guide for informed decision making and strategies to ensure the sustainable functionality of maritime infrastructure in Pulau Baai and similar coastal regions. [ABSTRACT FROM AUTHOR]

Marine resource subsidies alter consumer dynamics of recipient populations in coastal systems. The response to these subsidies by generalist consumers is often not uniform, creating inter- and intrapopulation diet variation and niche diversification that may be intensified across heterogeneous landscapes. We sampled western fence lizards, Sceloporus occidentalis, from Puget Sound beaches and coastal and inland forest habitats, in addition to the lizards' marine and terrestrial prey items to quantify marine and terrestrial resource use with stable isotope analysis and mixing models. Beach lizards had higher average δ13C and δ15N values compared to coastal and inland forest lizards, exhibiting a strong mixing line between marine and terrestrial prey items. Across five beach sites, lizard populations received 20–51% of their diet from marine resources, on average, with individual lizards ranging between 7 and 86% marine diet. The hillslope of the transition zone between marine and terrestrial environments at beach sites was positively associated with marine-based diets, as the steepest sloped beach sites had the highest percent marine diets. Within-beach variation in transition zone slope was positively correlated with the isotopic niche space of beach lizard populations. These results demonstrate that physiography of transitional landscapes can mediate resource flow between environments, and variable habitat topography promotes niche diversification within lizard populations. Marine resource subsidization of Puget Sound beach S. occidentalis populations may facilitate occupation of the northwesternmost edge of the species range. Shoreline restoration and driftwood beach habitat conservation are important to support the unique ecology of Puget Sound S. occidentalis. [ABSTRACT FROM AUTHOR]

With the ever-increasing emphasis on climate change and sustainability, there is growing interest in using environmentally friendly coastal structures. In addition to engineering and cost factors, the construction global warming potential (GWP) can and should be an influencing factor in the selection and design of the structures. Therefore, knowledge of construction GWP facilitates informed decision-making in coastal projects to achieve climate goals. Considering the number of Icelandic-type berm breakwater (IceBB) structures worldwide, this structure's design method is commonly accepted in coastal protection projects. In this paper, the construction process of an IceBB was assessed for its GWP and compared with concrete armor unit protection of a conventional rubble mound breakwater (ConRMB). The assessment and comparison were made for constructing a breakwater to protect the port of Thorlakshofn in southwest Iceland. The life cycle assessment (LCA) methodology was applied to calculate the construction carbon footprint of the structures using GaBi software, version 10.6.1. Using the International Union for Conservation of Nature (IUCN) criteria for nature-based solutions (NBS) and based on the existing literature, the characteristics of IceBB were briefly explored. The results showed that the construction of IceBB has a lower GWP than ConRMB, mainly due to using natural rock armor instead of concrete armor units. Furthermore, the results indicated that IceBB characteristics meet the IUCN criteria for NBS and thus can be granted as a (hard) NBS coastal structure. Acknowledging the advantages of IceBB, adopting this structure in coastal protection projects could meaningfully contribute to climate change mitigating policies. [ABSTRACT FROM AUTHOR]

Aangri, A.; Hakkou, M.; Krien, Y.; Chtioui, T., and Benmohammadi, A., 2024. Risk assessment of marine flooding along the Agadir and Taghazout coasts (Moroccan Atlantic). Journal of Coastal Research, 40(1), 179–192. Charlotte (North Carolina), ISSN 0749-0208. The Intergovernmental Panel on Climate Change's predictions highlight the probability that sea-level rise could exceed 1 m by 2100. As a result, coastal flooding episodes will increase. These will occur during events that simultaneously combine strong swells, spring tides, low-pressure conditions, and abnormally high surges. This behavior can seriously affect urban spaces along the sea. This paper investigated the risk assessment of marine flooding in the Agadir-Taghazout coastline by considering effects of the Sea Level Rise based on a hybrid model. The components of the hybrid model were obtained through NWW III (Wave Watch III), Simulating Wave Nearshore simulations of the propagation of the storm surge from the offshore to the nearshore, and by applying the Generalized Extreme Value method for Total Water Level (TWL) return value estimation. The simple static model calculates extreme levels based on the summation of tidal components, surge, run-up, and return value of TWL. The results obtained are mapped to determine the spatial extent on a height resolution Digital Terrain Model. Currently, the results of the study show, in first order, the high vulnerability of the southern part of the Agadir and Imourane beach. For future conditions, in 2100 the model predicts the submersion of the whole study area, threatening the infrastructures of the first line of the buildings facing the sea. This calls on, from now, the managers of this coast to prepare a protection strategy against this risk. [ABSTRACT FROM AUTHOR]

Intertidal ecology has been considered the cradle of modern marine ecology with insightful investigations on the biological and ecological mechanisms allowing "life between the tides". Most of the early investigations focused on macrophytes (seagrasses and macroalgae) and benthic invertebrates inhabiting emerged intertidal substrata. However, tidepools also shelter a rich fauna, including fishes, which display a wide diversity and a variety of ecological interactions and functions. Here, we review the diversity, ecology, evolution and conservation of the American tidepool fishes, from definition to trophic roles, ecological vulnerabilities and societal importance that reveal an extraordinary biodiversity and the important roles fishes play in the coastal ecosystems. Tidepool fish studies increased sharply from the mid twentieth century onwards, but many geographic gaps still exist. Tidepool fishes connect marine and terrestrial communities via substantial predation upon insects and exporting energy to land as prey for terrestrial fauna. Sea-level rise driven by climate change will reduce or eliminate current intertidal habitats, where little or no space is available for landward accommodation in the supralittoral zone. Concurrently, tidepool habitat would be 'squeezed' to a narrow intertidal stripe by 'coastal squeeze' process. Endemic, habitat-restricted, and specialist species could be particularly affected by human-induced habitat loss on the coastal stripe. Tidepool fishes provide many ecological services, such as well-being, environmental awareness, outdoor recreation, and bioinspiration for ancient and current societies. The level of intertidal rocky shore protection varies among American countries, but in most cases rocky shores are included in the least effective protection categories allowing extractive activities. [ABSTRACT FROM AUTHOR]

In parallel with many other countries, the government of Japan has started to tackle coastal adaptations to climate change. In 2020, the national Basic Policy for Coastal Protection was revised to add the statement that coastal management should account for future changes in coastal hydrodynamic conditions due to climate change. Following this policy, the management body of each coast is requested to revise the Basic Plan for Coastal Protection by 2025. This paper first reviews the current legal frameworks and measures of coastal protection and conservation, such as disaster prevention and mitigation against stormy waves, storm surges and tsunamis, beach conservation, and maintenance of coastal protection facilities. Second, the paper outlines the recent actions taken for coastal adaptation to climate change. With example cases in Osaka and Tokyo bays, it is described how design conditions such as design waves and water levels should account for the influence of climate change. It is also described how adaptive beach management should be implemented accounting for projections of future beach changes. Finally, the paper discusses future challenges in coastal adaptation strategies to climate change in Japan, such as introduction of integrated coastal zone management and other potential options that have not been implemented in Japan. [ABSTRACT FROM AUTHOR]

Shenzhen is a crucial city in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA). With high-intensity land development and rapid population growth, the ocean has become an essential space for expansion, leading to significant variations in water quality in the coastal area of Shenzhen. Water clarity (Zsd) is a key indicator for evaluating water quality. We applied the quasi-analytical algorithm (QAA) to Sentinel-2 data and retrieved the Zsd of the coastal area of Shenzhen. By adjusting the red band for distinguishing water types, we avoided underestimating Zsd for clear water. This study pioneered the production of a 10 m Zsd product for the coastal area of Shenzhen from 2016 to 2021. The results showed that the coastal area of Shenzhen exhibited a spatial distribution pattern with low Zsd in the west and high in the east, with Pearl River Estuary (PRE: 0.41–0.67 m) and Shenzhen Bay (SZB: 0.30–0.58 m) being lower than Dapeng Bay (DPB: 2.7–2.9 m) and Daya Bay (DYB: 2.5–2.9 m). We analyzed the seasonal and interannual variations and driving factors of the four areas, where PRE and SZB showed similar variation patterns, while DPB and DYB showed similar variation patterns. PRE and SZB are important estuaries in southern China, significantly affected by anthropogenic activities. DPB and DYB are important marine aquaculture areas, mainly affected by natural factors (wind speed, precipitation, and sea level). The Zsd of the coastal area of Shenzhen, along with the analysis of its results and driving factors, contributes to promoting local water resource protection and providing a reference for formulating relevant governance policies. It also provides a practical method for assessing and monitoring near-shore water quality. [ABSTRACT FROM AUTHOR]