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Guru Prasath, J.; Sannasiraj, S.A., and Chandramohan, P., 2024. Nearshore morphological changes due to severe cyclonic storm activity along the east coast of India. Journal of Coastal Research, 40(4), 696–713. Charlotte (North Carolina), ISSN 0749-0208. Nearshore waves, wind, and tidal current mobilize seabed sediments; sort, transport, and redistribute the sediments; and modify the nearshore seabed morphology. Waves play a dominant role in morphological changes among winds, waves, and tidal currents. The nearshore wave breaking induces the initiation of sediment movement, and the associated alongshore current transports a large volume of sediments that tend to either accrete toward or erode from the beach face and seabed. Sediment transport rate in the nearshore waters during cyclones is higher than that under normal conditions. The measured changes due to Cyclone Nivar in November 2020 in the nearshore morphology along the Mahabalipuram coast are examined to understand the response of nearshore morphology to cyclonic wave-induced forcing. The beach-profile measurements across 10 transects at 100 m spacing covering about 1000 m along the coast were measured before and after the passage of Cyclone Nivar as a part of the present field study. The evolving beach profiles during Cyclone Nivar were simulated using the storm-induced beach change (SBEACH) model, which is a cross-shore profile evolution model. The changes due to berm erosion and deposition of nearshore sand bars have been compared from field measurements data and model prediction. The calibrated model was then used to simulate the beach profile response at two other locations along the cyclone-affected coastline to examine the shoreline impact. The calibrated model can be used along the coast to understand the poststorm profiles of the beach with reasonable accuracy. [ABSTRACT FROM AUTHOR]

AlMashan, N.; Al-Attar, I., and Neelamani, S., 2024. Assessment of annual sedimentation into Failaka Marina (Kuwait) and possible solutions for reduction of siltation. Journal of Coastal Research, 40(3), 527–553. Charlotte (North Carolina), ISSN 0749-0208. Sedimentation is critical for ports, harbors, and marinas, requiring accurate assessment. Failaka Marina in Kuwait is experiencing a severe noncohesive sedimentation problem. The samples collected at the seven locations along the beach showed that the beach has a uniform grain-size diameter, meaning it is poorly graded sand. The sampling at the tip of the southern breakwater showed that the shoaling is mainly sand. The suspended-sediment concentration varies from 0.025 kg m–3 to 1.2 kg m–3, whereas the mean concentration at the marina entrance is 0.85 kg m–3. The time series of the suspended solids over a year in the seawater surrounding Failaka Island shows a range of 8 to 48,069 ppm. Such a considerable variation in suspended load is due to the massive amounts of dredging and spoil disposal at Boubyan Island and Basra Port (Iraq) when a high sediment load moves around Failaka Island with a concentration of more than 40,000 mg L–1. Annual sedimentation is about 2.35 m y–1, which is responsible for blocking the main entrance for navigation. Kuwait's Ministry of Communication allocates $4 to $6 million annually for dredging and disposal activities. This study evaluates the six marina entrance modification scenarios to determine the best scenario that achieves a measurable reduction in sedimentation rate in the Marina. Six marina breakwater modifications were studied, and annual sedimentation rates were numerically computed. The study use Coupled MIKE 21/3 to simulate hydrodynamic conditions for cohesive sediment transport in a problem area. Field data from 2015 calibrated and validated the model. The primary sediment-moving force is SE wind and sea-swell waves. Littoral drift along Failaka Island's southern coastline and high suspended-sediment concentration result in littoral drift and settling. The best scenario showed a 28% sedimentation reduction and a 26% reduction in maintenance dredging costs from the six studied scenarios. [ABSTRACT FROM AUTHOR]

Andrus, T.M. and Bentley, S.J., 2023. Capture timescale of an uncontrolled Mississippi–Atchafayala bifurcation with future lower river strategy implications. Journal of Coastal Research, 39(6), 1001–1020. Charlotte (North Carolina), ISSN 0749-0208. The most recent and currently active delta lobe of the Mississippi River (MR) is the Atchafalaya–Wax Lake lobe, which was initiated approximately 400 years ago as a result of MR stream capture by the Atchafalaya River (AR). This capture process accelerated in the early to mid-1900s but further development was prevented by construction and operation of the Old River Control Structure (ORCS) complex in 1962. Because the initial research to warrant the construction of the ORCS was undertaken nearly 70 years ago, this study revisits the basis of the resulting predictions and evaluates how both branches could evolve moving forward both with and without ORCS controls. This study uses the Delft3D software suite to retest the capture hypothesis by accounting for complex hydrodynamic interactions from the MR/AR bifurcation to the Gulf of Mexico. A 150-year model duration was used to adequately characterize bifurcation evolution, stream capture life cycle, and long-term river management concerns. Results of modeled flow evolution with the ORCS removed indicate a rapid period of channel adjustment followed by a long and gradual increase in flow ranges and magnitudes in the AR similar to those currently in the MR. In this hypothetical scenario, the AR captures 50% of the MR very quickly (∼17 y) to become the dominant stream and then the capture rate begins to decelerate. One-hundred-fifty-year results with ORCS controls remaining unchanged reveal increased sedimentation, rising stages, and decreased stream power in the MR. Conversely, AR results indicate channel deepening, stage lowering, and increased sediment-transport efficiency. These trends suggest that although the flow split at the MR/AR bifurcation continues to be regulated by the ORCS, the geologic evolution toward capture gradually continues. This study presents a long-term view of an uncontrolled MR/AR avulsion, and capture results reiterate the ORCS's importance to socioeconomic factors such as flood control and navigation. However, results also reveal long-term sustainability concerns for the MR system associated with current ORCS flow regulation. Predictive modeling tools such as those developed in this study could be used to optimize ORCS management strategies and potentially enhance ecosystem restoration plans. [ABSTRACT FROM AUTHOR]

Liang, Z.; Ji, D.; Zhang, X.; Lingyun, W.; Zhang, T.; Li, S.; Yong, J.; Luo, J.; Liu, Y., and Zeng, J., 2023. Carboniferous oceanic basin sediment-gravity flows in the margin of the Junggar Basin, NW China: Characterisation and implications for hydrocarbon potential and evolution pacing. Journal of Coastal Research, 39(5), 890–906. Charlotte (North Carolina), ISSN 0749-0208. Several Carboniferous deep-marine-sandstone reservoirs have recently been discovered in the Junggar Basin, NW China. These reservoir sandstones were deposited by sediment-gravity flows that occurred on the continental slope of the Junggar Basin, and they have high hydrocarbon exploration potential. In this study, careful observations and petrological and geochemical analyses of samples from outcrop sections of Carboniferous rocks from the Junggar Basin were conducted to establish the deep-marine sedimentary characteristics, depositional environments, and mechanism of these gravity-flow deposits, as well as a sedimentary model for their occurrence. The deep-marine, gravity-flow deposit types include those of turbidity currents, debris flows, and slumps. The debris-flow deposits can be divided into pebbly debris-flow deposits and sandy debris-flow deposits. Results allow the relationship between the type and nature of gravity flows and ocean basin evolution to be established. During the early Carboniferous, the ocean basin had sufficient space to accommodate incoming sediment, and the sediment transport distance was long. The gravity-flow sediments of this period are dominated by sandy debris-flow deposits and turbidity-flow deposits characterised by thin individual layers but thick accumulations of multiple deposits. With continuous narrowing of the oceanic basin during the late Carboniferous, the basin had a smaller accommodation space. The main types of gravity-flow deposition during this period were pebbly and sandy debris flows, with rare thin turbidity-flow deposits. These deposits were coarser grained than their early Carboniferous equivalents, and their cumulative thicknesses were smaller. The results of the study provide insights into the prediction of deep-marine reservoir sandstones and the distribution of hydrocarbons in the Junggar Basin. [ABSTRACT FROM AUTHOR]

Kim, Y.-j. and Yoon, J.-s., 2023. Shoreline variation prediction of the Jeongdongjin Sea area considering effective sediment volumes. Journal of Coastal Research, 39(1), 154–166. Charlotte (North Carolina), ISSN 0749-0208. The coastal erosion in the East Sea region of Korea has been increasing because of the imbalance in the effective sediment volume and sediment transport from coasts and rivers, which causes intermittent erosion and sedimentation. The accurate prediction of the coastal sediment budget is an extremely difficult task because the sediment transport mechanism on the coast is highly complex. Studies considering the effective sediment volume supplied through rivers remain limited, although many other studies have focused on identifying the characteristics of sediment transport on the east coast. The grain-size distribution of the soil on the coast is considered the single-grain size (D50); however, the grain-size distribution of sediments flowing into and out of the coast and the topographical characteristics of the sea area need to be considered to predict shoreline variation with a high degree of accuracy. Thus, this study conducts in-depth analysis on the changing state of soil movement in wave-current co-existing fields (mountain, river, and coastal areas). The objective is to predict shoreline variation considering the environment of the Jeongdongjin Sea area by establishing a quantitative evaluation system of the effective sediment volume discharged from the area of river mouth bars. An effective sediment volume was evaluated using a sediment runoff model; the wave transformation for each survey line was calculated using SWAN to consider the wave characteristics acting on the sea area. The prediction performance was greatly improved by applying the mixed grain size to the soil in the sea area and by applying jetties to the reefs for upgrading the prediction of the shoreline variation. [ABSTRACT FROM AUTHOR]

Liu, Z.; Zang, J., and Liu, J., 2023. Preliminary analysis of reclamation changes in Macao using multisource and multitemporal remote-sensing data. Journal of Coastal Research, 39(1), 90–102. Charlotte (North Carolina), ISSN 0749-0208. Macao is a typical reclamation city. A systematic analysis of reclamation changes can be used to relate reclamation to socioeconomic development. In this study, multisource and multitemporal satellite remote-sensing data were used to analyze the temporal and spatial characteristics, driving forces for reclamation, and nearshore water quality of Macao. The results showed that the Macao coastline is moving towards the sea. The total area of Macao increased from 29.19 km2 in 1999 to 35.83 km2 in 2019. The largest proportion of reclamation land-use type was public facilities land, whereas the smallest proportion was green land and square land. The land distribution gradually became more compact up to 2007 and dispersed thereafter. The factors of population, gross domestic product, number of visitors to Macao, and total export trade had different influences on reclamation in Macao during different time periods, where the population factor had the largest overall impact. The concentrations of chlorophyll and suspended sediment in Macao coastal waters were high nearshore and low offshore. [ABSTRACT FROM AUTHOR]

Mercaldi, B.; Brideau, L.E.; Tait, J.F., and Griggs, G., 2022. Seasonal morphological variability on estuarine beaches and implications for low-energy beach management. Journal of Coastal Research, 38(6), 1135–1147. Coconut Creek (Florida), ISSN 0749-0208. Estuarine beaches and other low-energy shorelines are critical for habitats and coastal infrastructure protection. Many different species inhabit estuaries because of the water bodies' unique characteristics, such as their mixed seawater and freshwater and variable tidal ranges. Estuarine beaches also have the important role of buffering storm wave energy. Yet, their natural physical processes are understudied. This research focuses on seasonal morphological variability of estuarine, low-energy beaches and evaluates the implications for beach management practices. Five sandy beaches were studied along the northern shoreline of Long Island Sound in the northeastern region of the United States. The studied beaches vary in location, width, length, and orientation within Long Island Sound to represent different exposures to wave energy. Three seasonal profiles were measured at each beach approximately every four months from late 2015 to early 2019 to document topographic changes. The results revealed minimal sediment movement throughout the study period and there was no evidence of significant cyclic cross-shore sediment transport to indicate patterns of seasonal profile changes. These findings reveal important implications for beach management practices on low-energy shorelines. Specifically, estuarine and other low-energy beaches should be studied on decadal time scales to document any long-term variability and post-storm recovery rather than the monthly or yearly time scales on which open-ocean beaches are typically evaluated. Additionally, estuarine beaches and other low-energy shorelines require specialized management practices that cater to their stagnancy to ensure adequate protection of coastal structures and infrastructure in the face of intensifying hurricanes and sea level rise. [ABSTRACT FROM AUTHOR]

Cheng, J. and Wang, P., 2022. Factors controlling storm-induced morphology changes at an erosional hot spot on a nourished beach, Sand Key barrier island, west-central Florida. Journal of Coastal Research, 38(4), 750–765. Coconut Creek (Florida), ISSN 0749-0208. Beach nourishment has become the dominant sandy shore protection method over the past 40 years. The performance of nourished beaches and therefore the design of renourishment projects are significantly controlled by the presence of erosional hot spots and storm impacts. Based on 5.5-year bimonthly beach profile surveys, along a nourished beach spanning an erosional hot spot, this study examines the hydrodynamic conditions of extratropical (winter) and tropical (summer) storms that cause significant morphology changes. The sand volume loss above the short-term closure depth averaged along the 1.8-km stretch erosional hot spot was 178 m3/m over the 5.5 years after the nourishment. A large portion of this volume loss was caused by several extratropical storms and Hurricane Irma in 2017, when the high, northerly approaching waves were associated with a depressed water level. The northerly approaching waves induced a large longshore sediment transport gradient along the generally north-south trending coast due to wave refraction over a nearby ebb tidal delta. The energetic Hurricane Irma induced a large negative surge and also transported sediment seaward beyond the short-term closure depth. On the other hand, during the passages of typical tropical storms, the southerly approaching waves superimposed on elevated water levels caused substantial beach volume loss above the mean sea level. The eroded sediment deposited on the nearshore sandbar, resulting in conserved sand volume above the short-term closure depth. Understanding the different beach response to extratropical and tropical storms would benefit beach management, especially under the circumstance of increasing storm activities due to climate change. [ABSTRACT FROM AUTHOR]

Windom, H.L. and Palmer, J.D., 2022. Changing river discharge and suspended sediment transport to the Georgia Bight: Implications to saltmarsh sustainability. Journal of Coastal Research, 38(3), 512–522. Coconut Creek (Florida), ISSN 0749-0208. Suspended sediment delivered in river discharge to the Georgia Bight (the coastal-shelf area of the SE U.S. Atlantic coasts of Georgia and South Carolina) provides a continuous supply of fine grain sediments to support coastal saltmarshes. Archived data on discharge and suspended sediment loads for Piedmont and Coastal Plain rivers collected over eight to nine decades were used to estimate the present rate of sediment discharge to the Bight to be about 1 × 106 metric tons annually. The data used in this assessment are for the period after major reservoir/dam construction and other streamflow diversions occurring during the 1950s–1970s, which had a major effect on sediment yields of SE Atlantic watersheds. The estimated annual sediment delivery is about two-thirds of that needed to maintain vertical saltmarsh stability as sea level rises at the present regional rate of 3.3 mm/y. The observed 2% per decade decreasing trend in river discharge to the Bight, related to rapid population and temperature rise since ca. 1960, and the continual depletion of sediment stored in river floodplains below dams, suggests that the fine sediment supply to the coast will continue to decline. [ABSTRACT FROM AUTHOR]

Akiner, M.E. and Lačnjevac, C., 2022. Managing saltwater intrusion and agricultural practices along the Boăaçay River, Turkey: Effects from excavation and land source pollution. Journal of Coastal Research, 38(3), 567–577. Coconut Creek (Florida), ISSN 0749-0208. The Boăaçay is a river situated in the Konyaaltı district of Antalya. In 2017, Antalya Metropolitan Municipality implemented a large project in which the river bed was excavated to 1.5 m below sea level. The aquifer is vital for meeting the drinking water needs of the city of Antalya. The goal of this research is to discover the applications that may be made to combat seawater intrusion and nutrient contamination, both of which were brought to the forefront by the Boăaçay Project. In this work, modeling was used to estimate the extent to which agricultural best management practices (BMPs) will be efficient in reducing pollutant load. In BMP modeling with the soil and water assessment tool (SWAT), a decrease of 39%, 38%, and 38% is anticipated in the 5-day biochemical oxygen demand (BOD5), total phosphorus, and total Kjeldahl nitrogen loads, respectively. Sediment accumulated in the channel, and sediment transport occurred on the beach due to coastal erosion. Coastal erosion of up to 25 m was observed from the project's beginning to the present. Substantial land base pollution because of the diffused sources was found. Saltwater intrusion in the Boăaçay River estuary functions as a catalyst in the production of poor odor and appearance, as well as the rapid expansion of algae. The municipality is attempting to remedy this problem by periodic harvesting, which is an overly expensive and ineffective option. Instead, the elevation of the riverbed should be restored to preproject levels to prevent additional environmental and geographic damages. [ABSTRACT FROM AUTHOR]

Youn, S. and Zarillo, G., 2022. Morphological analysis of barrier islands in the Nakdong River Estuary, South Korea. Journal of Coastal Research, 38(3), 475–490. Coconut Creek (Florida), ISSN 0749-0208. The Nakdong Estuary system and the associated barrier island system near Busan, South Korea, consists of dynamic shorelines characterized by morphological transformations that result from natural disasters (typhoons and flooding), rising sea levels, and construction projects (the Nakdong Estuary Dam and the Busan Newport). This study aims to synthesize existing water level, wave, meteorological, and morphological data obtained from various institutions with the objective of identifying major factors that influence shoreline and area change over time. These objectives were met by analyzing the shoreline and area with direction analysis from center point (DACP) to consider the influence of river discharge and sea-level rise and to determine shoreline shifts in barrier island orientation over time. From DACP, it was determined that the Nakdong barrier islands rotated clockwise because of erosion and deposition. Offshore shorelines of barrier islands advanced by 0.1 to 2 km between 1972 and 2013. The area change rate between 1972 and 2013 was 20.85% from 100 to 180° because of the Maenggeummeori-do channel construction and discharge from the Nakdong Estuary Dam. Morphological changes and shifts in shoreline positions were caused by alteration of flow patterns because of construction of the Nakdong Estuary Dam and sea-level rise in the Nakdong Estuary system based on the timeline of the shoreline and area change rates. This study exemplifies the need for a preconstruction development plan in a study area to ensure that the results of a project are environmentally sound with respect to the potential impacts of project construction and sea-level rise. [ABSTRACT FROM AUTHOR]

Black, K.P.; Baba, M.; Mathew, J.; Kurian, N.P., and Ilic, A., 2021. Guidelines to prepare India's coast for climate change. Journal of Coastal Research, 37(6), 1117–1129. Coconut Creek (Florida), ISSN 0749-0208. India's first coastal protection guidelines for climate-change adaptation are described. The guidelines are holistic, recognizing the links between engineering, economic, physical, legal, social, environmental, and governmental intricacies. Robust protection solutions under climate change for millions of coastal residents may occur only when all these facets are improved within the complex regulatory, budgetary, and practical circumstances in India. Fifty-seven specific guidelines are presented in nine categories ranging from administrative to best-practice coastal protection. An "environmental softness ladder" that ranks coastal protection methods was developed as a scientific tool to guide policy development and project implementation. "Minimum floor level" for safe building was defined for each Indian coastal state using climate-change data produced for the study by Indian and international institutes. Beaches are more stable when the net sediment transport fluxes are close to neutral. "Grand schemes," which make large-scale changes to the coast rather than continuing with piecemeal localised works, are recommended. With diverse dynamics over a long coastline in India, the 4-year study engaged an exceptionally large number of experts, agencies, government bodies, development partners, and other stakeholders. [ABSTRACT FROM AUTHOR]

Whitley, A.E.; Figlus, J.; Valsamidis, A., and Reeve, D.E., 2021. One-line modeling of mega-nourishment evolution. Journal of Coastal Research, 37(6), 1224–1234. Coconut Creek (Florida), ISSN 0749-0208. As many coastal areas of the world suffer from chronic erosion, innovative solutions beyond traditional local nourishment must be explored. One such solution is the implementation of mega-nourishments (MNs), where a large sediment volume is deposited in a single location and redistributed via natural processes, thereby feeding adjacent beaches. Robust numerical modeling methods are needed to evaluate potential MN sites at coastal locations around the world. Two one-line numerical modeling approaches of MN evolution are presented using the Coastline Evolution Model (CEM) and GENESIS + Cascade (GenCade). Both models are parameterized for the Sand Motor (SM) that has been constructed on the Dutch coast to explore the feasibility of the MN approach. Here, a variety of K coefficients in the Coastal Engineering Research Center (CERC) sediment transport equation are tested since traditionally calibrated and used values may not apply for MN features. Both models are found capable of reproducing the shoreline morphological patterns observed at the SM over the first 3.5 years. GenCade shows a low difference between measured and modeled coastline position overall, showing accurate predictions of absolute shoreline position. CEM is able to capture feature tip migration due to its wave shadowing algorithm. The best results from both models can be obtained for higher K values than those commonly suggested in the literature. Given the size of a mega-nourishment relative to traditional nourishments, it is likely that a higher-than-usual K value may be a better fit when simulating mega-nourishments in a one-line model. [ABSTRACT FROM AUTHOR]

Jo, Y.J. and Cho, Y.J., 2023. How the beach restoration process, driven by bound mode infra-gravity waves underlying swells in a mild sea, is affected by the presence of LCB: A numerical study. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 618-622. Charlotte (North Carolina), ISSN 0749-0208. This study aims to numerically investigate the impact of Low Crested Breakwater [LCB] on the beach restoration process driven by bound mode infra-gravity waves beneath swells in a mild sea. In doing so, the authors also delve into the evolving extent of boundedness of infra-gravity waves to a wave packet during shoaling. Additionally, the authors explore the effects of this evolution on sediment transport. The infra-gravity waves were extracted from a numerically simulated wave field using the Empirical Mode Decomposition method. Numerical results reveal a transition in the cross-correlation between a wave packet and infra-gravity waves from negative to positive during shoaling, especially when the phase of infra-gravity waves is initially shifted by as much as π. These correlation patterns align well with the wave data acquired by Abdelrahman and Thornton. Furthermore, the degree of boundedness of infra-gravity waves to a wave packet has a significant impact on the sediment transport rate. When fully phase-locked, a substantial amount of sand, in the form of bedload, escapes offshore through the open inlet between LCB. Approximately 5 × 10–3m3/m of sand exits the inner zone of LCB per unit amplitude modulation period of a wave packet. Conversely, with a phase shift of π, the primary sediment transport mode at the open inlet between LCB becomes bedload. Sand migrating toward the shore balances with offshore-directed sediment transport, marking a departure from previous studies focused on monochromatic waves only. [ABSTRACT FROM AUTHOR]

Muin, M. and Muslim, A.B., 2023. Anak Krakatau Landslide Tsunami and sediment transport simulation using non-orthogonal boundary fitted technique in spherical coordinate model. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 146-150. Charlotte (North Carolina), ISSN 0749-0208. This paper presents a simulation of a tsunami induced by the Anak Krakatau Landslide in Indonesia and the sediment dispersion transported by the tsunami. The hydrodynamic model of this simulation used a non-orthogonal curvilinear technique in Spherical Coordinates and was developed in GIS on Windows System, named MuTsunami. The advantages of MuTsunami are rapid computation, accurately solving complex geometry, and integrating with the sediment transport model. This software is suitable for an early warning system. MuTsunami has also been applied in the 2010 Mentawai and 2004 Aceh Tsunami. The results show good agreement with the observation data. The simulation results indicate that the tsunami reached Serang, Ciwandan, Kota-Angung, and Panjang within 1860, 2760, 2100, and 4140 seconds after the Anak Krakatau Landslide occurred. The waves along the coast occurred up to 9 m and 8 m for Banten and Lampung coasts. The sediment transport result shows bathymetric changes along the Banten coast 30 minutes after the landslide. The required time to simulate the tsunami from the Anak Krakatau Landslide is only 15 seconds which is suitable for an early warning system. [ABSTRACT FROM AUTHOR]

Fitria, J.; Gemilang, R.I.A.; Purnama, B., and Prasetyo, A., 2023. Rapid changes in the coastal morphology of Amurang, North Sulawesi, Indonesia. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 289-293. Charlotte (North Carolina), ISSN 0749-0208. Changes in coastal morphology can occur through long-term processes, such as sediment transport, and through short-term processes, such as those caused by earthquakes, storms, or tsunamis. On June 15th, 2022, a rapid change in coastal morphology due to a landslide happened in the coastal area of Amurang, North Sulawesi, Indonesia. Morphological changes and their triggers were analyzed through a comparison of post-slide and preslide bathymetry data, satellite imagery, and analysis of the soil layers. Based on the comparison of bathymetry data, the maximum change in seabed depth in the landslide area was 51 meters with a curvature shape on the rupture surface. The coastline has retreated about 150 meters inland with around 2.34 million m3 of material displaced. The results show that the landslides on the Amurang Coast that caused the rapid morphological change in the area were not triggered by hydro-oceanographical conditions, tectonic events, or volcanic events. They were triggered principally by the over-steepened slope and the ground soil's ability to support the additional weight of building embankments over a thick sediment layer. [ABSTRACT FROM AUTHOR]

Hwang, B.-H.; Do, K.-D., and Chang, S.-Y., 2023. Morphological response of Storm Hinnamnor at Songjeong Beach using UAV-derived data. In: Lee, J.L.; Lee, H.; Min, B.I.; Chang, J.-I.; Cho, G.T.; Yoon, J.-S., and Lee, J. (eds.), Multidisciplinary Approaches to Coastal and Marine Management. Journal of Coastal Research, Special Issue No. 116, pp. 126-130. Charlotte (North Carolina), ISSN 0749-0208. This study investigated the morphological response of a wave-dominated beach to large storms via field data collection. The field data were collected on Songjeong beach facing SE in the south-eastern corner of Korea. This study measured pre- and post-storm beach volumes by Storm Hinnamnor using Unmanned Aerial Vehicle (UAV). In this storm event, the peak of the significant wave was 10 m, and the wave period mainly varied between 10.9s under stormy conditions. The incident waves were mostly easterly at 90-115.5°. During this event, due to the strong storm intensity, the upper part of the sediment showed significant erosion along the entire beach, and net accumulation took place in the revetment area by overwash. The highest substantial loss occurred in the SW section of the study area, associated with the wave direction. Compared to the SW section, the mid and NE section of the study area eroded sediment. It was transported to the upper beach near the revetment area, suggesting that the onshore sediment transported was dominated in this area. After the storm, the local government undertook beach nourishment to restore the deposition sand on the revetment to the beach. This study carried out the UAV survey after beach nourishment and estimated the sediment volume by overwash. As a result, it was estimated that the amount of sand transported to the offshore area was 9533 m3, and the overwash deposition volume was 1441.3 m3. This study shows that UAV surveys can effectively estimate the morphological response of storm on the beach. [ABSTRACT FROM AUTHOR]

Yang, Z.; Chen, D.; Huang, D., and Yang, Y., 2019. Prediction of coastal evolution in Puerto Cabello, Venezuela. In: Guido-Aldana, P.A. and Mulahasan, S. (eds.), Advances in Water Resources and Exploration. Journal of Coastal Research, Special Issue No. 93, pp. 16–21. Coconut Creek (Florida), ISSN 0749-0208. Coasts vary in their composition and the physical processes that affect them. However, their nature and behavior have similarities. Presently, the majority of coasts worldwide are eroding. The rapidly increasing threat of global warming and the resulting rise in sea level can accelerate coastal erosion. The nearly 2 km coastline in the port city of Puerto Cabello in Venezuela, to the west of the island Goaigoaza, was taken as a case study. The long-term state of the beach was assessed by considering the credits and debits of sand that pass through the coastal system. In the study, the net longshore sediment transport rate in the west of the salient was westward and Qin < Qout, denoting that beach erosion will occur in this particular area. Through field investigations and theoretical analysis, it can be preliminarily concluded that the beaches in the study area are slightly eroded. However, a long-term study on the current profile is essential to arrive at a decisive conclusion. [ABSTRACT FROM AUTHOR]

Muin, M., 2021. Sediment dispersion modeling of a non-orthogonal boundary fitted technique: Mangrove reclamation to protect cliff erosion in Bintuni Bay, Indonesia. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 544–548. Coconut Creek (Florida), ISSN 0749-0208. Bintuni Bay is a semi-closed bay located in West Papua Province, Indonesia. The facility of Tangguh LNG Project was faced serious problems due to erosion along the cliff. It was decided that reclamation is the best solution. Mangrove trees are planted in the reclamation area to reduce the wave. The reclamation was designed until one meter below highest water spring to allow seawater to flow in and out through the inlet/outlet. This paper presents and discusses simulations for several options of reclamation layout, inlet/outlet, during and after reclamation. MuSed3D, the 3D ocean hydrodynamics and sediment transport model using non-orthogonal boundary fitted technique, was employed to conduct the simulation. [ABSTRACT FROM AUTHOR]

Kim, T.K.; Jeong, J.H., and Lee, J.L., 2021. Shoreline variation analysis by cross-shore sediment transport resulting from effects of storm waves. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 539–543. Coconut Creek (Florida), ISSN 0749-0208. Coastal beach erosion is affected by not only the wave energy of a storm wave, but also its duration. Therefore, this study analyzes the duration characteristics for different storm wave scenarios using wave data obtained over 40 years; these data were provided by the National Oceanic and Atmospheric Administration (NOAA). Further, the vulnerability of shoreline erosion deduced from the correlation between the cumulative breaking wave energy and observed shoreline variability was discussed. To analyze the duration of storm wave scenarios, we propose dimensionless characteristics for peak wave height per storm wave scenario and a representative mathematical function for storm wave scenarios. Shoreline variability is calculated using the shoreline survey data for Bongpo Beach, located on the eastern coast of South Korea, measured quarterly for nine years. The cumulative breaking wave energy flowing into the beach generally exhibited a linear relationship with the shoreline variability. Therefore, this study suggests a simple method to determine the extent to which the shoreline retreats given the peak wave height of the incoming wave scenario. [ABSTRACT FROM AUTHOR]

Vu, X.H. and Lee, J.L., 2021. Simulation study of scarp and berm formation using a suspended sediment transport model. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 504–508. Coconut Creek (Florida), ISSN 0749-0208. Beach berms and scarps are common morphological features that develop repetitively due to the cyclic incidence of mild and storm waves. However, beach scarp and berm formations, as well as their morphodynamics, have not been researched thoroughly. In particular, scarp generation is often observed at nourished beaches or under the incidence of oblique storm waves; scarps can pose severe risks to beach users and negatively impact local ecosystems. A numerical study was conducted using a suspended sediment transport model developed in a previous study to quantify the morphodynamic responses of beach berms and scarps to the foreshore region as well as offshore sand motion. In the present study, the destructive beach slope at the foreshore was controlled using Kim's empirical formula on the foreshore slope. [ABSTRACT FROM AUTHOR]

Lee, J.L. and Cho, Y.-J., 2021. Numerical analysis of sediment transport rates from rip currents at an open inlet between Low Crested Breakwaters (LCB): The role of infra-gravity waves. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 489–493. Coconut Creek (Florida), ISSN 0749-0208. Low Crested Breakwaters (LCB), the most preferred structural type in the coastal zone management project by the Korean Ministry of Ocean and Fisheries, has been designed to mitigate beach erosion by high waves occurring only a few times a year. Now that moderate sea conditions are dramatically different from those in rough seas, these poor design practices could interrupt the grand circulation process of natural beaches over the course of a year. As a result, the beach stabilizing effect of LCB often falls short of our expectations. In this study, in order to test this hypothesis, 3-D numerical simulation was carried out to analyze the rip currents and its associated sediment transport at the open inlet between LCB when LCB is subject to infra-gravity waves, which play an indispensable role in the beach restoring process in a mild sea with an annual prevalence rate of over 80%. Numerical results show that in the case of LCB with lower crest freeboard, rip currents gets increased by 2.6 times when compared to the one before the deployment of LCB since the water mass influx toward the down-wave side of LCB by overflowing LCB by the preceding waves is redirected toward the open inlet. The sediment transport rate was estimated using Bailard's model, the most referred cross-shore sediment model in the literature. It was shown that the primary sediment transport mode at the open inlet between LCB was bed load, and sand of 5.62 ×10–5m3 / m was leaving the inner zone of LCB per unit wave period. [ABSTRACT FROM AUTHOR]

Yoo, H.J.; Kim, D.H.; Park, M.H., and Lee, S.O., 2021. Economic sediment transport control with sediment flushing curves for sea dike gate operation: Case study in Saemangeum Basin, Korea. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 161–165. Coconut Creek (Florida), ISSN 0749-0208. As the major reclamation works in Korea, the sea dikes have been installed for preventing the saltwater intrusion in Saemangeum Basin connected with Mangyeonggang and Dongjingang River, Korea since 2010. Recently, the sedimentation issues near the gates due to change of flow velocity might induce serious problems such as water pollution, local scour, stability of hydraulic structures linked with dike. We focused that the gate operation rule was changed to alleviate the sediment transport problem by altering the management water surface elevation in this study. The 3D numerical model, SCHISM, was used to simulate the sediment transport under the gate operation rule which was embedded after modifying the hydraulics structure module in SCHISM. The numerical model was verified by comparing with the measured data in the literature. It was found that the phenomenon induced by gate operation was accurately simulated to compare with the field measurements from Korea Rural Community Corporation (KRCC). Based on the results of SCHISM, the Best Management Practices on gate operation were examined and suggested the optimal solution in terms of structural stability and water use including water quality. [ABSTRACT FROM AUTHOR]