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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]

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]

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]

Black, K.P.; Kulkarni, K.B.; Naik, G.B.; Naik, M., and Mathew, J., 2021. Improving training wall orientation at river and estuary entrances. Journal of Coastal Research, 37(3), 484–493. Coconut Creek (Florida), ISSN 0749-0208. Natural river and estuary entrances adjust in response to the prevailing sedimentary and hydrodynamic environment. In India, during the monsoon rains, the ebb jet can be very large, firing water and sediments along a variable orientation to create the associated ebb deltas. However, once the entrance is trained onto a fixed alignment, this powerful jet "pump" can have adverse impacts. Due to downdrift erosion caused by the entrance training walls at the Old Mangalore Port (Karnataka, west coast of India), the breakwater was modified to reorient the ebb jet in the direction of the longshore drift. The goal was to beneficially use the natural pumping action to drive sand across the entrance without mechanical assistance. Three years of monitoring revealed improvements in downdrift beaches and navigational safety, while maintenance dredging has ceased. The entrance region has deepened by 854,166 m3 after reorienting the ebb jet over the period from October 2017 to February 2020. In contrast, the entrance shoaled by 160,305 m3 over the period from September 2008 to October 2017. The results are relevant to river and estuary entrances with moderate to strong river flows and/or tidal prism. [ABSTRACT FROM AUTHOR]

Zhang, J.; Larson, M., and Ge, Z.P., 2020. Numerical model of beach profile evolution in the nearshore. Journal of Coastal Research, 36(3), 506–520. Coconut Creek (Florida), ISSN 0749-0208. A numerical model was developed to simulate hydrodynamics (waves, currents, and mean water level), cross-shore sediment transport, and beach profile evolution in the nearshore assuming negligible longshore transport gradients. Particular focus was put on describing the response of the subaerial region of the profile, including the foreshore and the berm, as well as the exchange of material between the swash and the surf zone. The model consists of different modules describing wave transformation, cross-shore currents, mean water elevation, and cross-shore sediment transport. For the purpose of model calibration and validation, detailed, high-quality data on hydrodynamics and beach profile response from the SUPERTANK data collection project were employed. The experimental cases studied encompassed several types of profile evolution, including berm erosion and bar formation, berm flooding and erosion, and offshore mound evolution for a narrow- and broad-crested mound. Overall, good agreement was obtained between calculations and measurements, especially for the foreshore and the berm, whereas the calculated bar shape was smoother than the measured shape. The model produced robust and reliable predictions of cross-shore transport and profile evolution for the cases investigated. Subsequent work in model development will involve dune erosion and overwash as well as validation toward field data. [ABSTRACT FROM AUTHOR]

Tak, W.J.; Jun, K.W., Kin, S.D., and Lee, H.J., 2020. Using drone and LiDAR to assess coastal erosion and shoreline change due to the construction of coastal structures. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 674-678. Coconut Creek (Florida), ISSN 0749-0208. Recently, The construction of structures on the coastal zone near estuaries, which are the supply sources of sediments, causes a variation in the waterway; this induces a change in the surrounding coasts, and the resulting coastal erosion can adversely affect the lives of the local residents. In the case of a balanced sediment flow, the quantity of the sediment deposited on the coast is equal to the quantity of the released sediment. However, an increase in either of the quantities causes an imbalance in the sediment transport; consequently, the sand is either deposited or eroded in the coastal or proximate shore regions. In this study, the changes in the shoreline and Wolcheon Beach region located on the east coast of Korea was monitored between 2010 to 2019 investigate the phenomena of coastal erosion and beach deformation. The shorelines, beach width, and beach profile were primarily monitored by employing a drone and a terrestrial LiDAR. The results showed that the sediments were transported northward in summer and southward in winter until 2010 in Wolcheon Beach; however, this seasonal sediment transport was blocked during 2011–2012 by the construction of coastal structures such as breakwaters, leading to partial coastal erosion and sedimentation. Wolcheon Beach originally had the coastal characteristics of the Korean East Coast region (2010), but the sediment transport changed due to the variations in the waterway by the construction of coastal structures, leading to a significant change in the coast (2011). In addition, the northern beach volume increased with respect to estuary, while the southern beach volume decreased. When the offshore breakwater was constructed, the northward sediment occurred dominantly in the shield area. In particular, the planar layout of the harbor facilities concentrated the waves, which increased the quantity of the northward sediment. [ABSTRACT FROM AUTHOR]

Parnell, K.E. and Smithers, S.G., 2020. Regional and local variability in coastal processes in Torres Strait, Australia, and its importance for climate change planning. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 616–620. Coconut Creek (Florida), ISSN 0749-0208. In small island states or regions, climate change planning is frequently undertaken at a country or regional level, and it is assumed that problems are common and that remedial actions can be widely applied. Community members observe treatments such as seawalls elsewhere and demand similar interventions even though they may be inappropriate. Torres Strait lies between mainland Australia and Papua New Guinea and has communities on a diverse range of islands including low muddy, coral cay, volcanic and continental island types. Approaches to solving problems caused by changing coastal processes on these varied shorelines are discussed at scales from regional to specific sites. Torres Strait has two distinct wind seasons which influence wave-driven processes and lead to seasonally reversing alongshore sediment transport, with shoreline dynamics also controlled by coastal orientation and the beach / reef flat interactions. The low muddy islands have limited management options, requiring shore protection and elevation. Shorelines on coral cay islands and the volcanic and continental islands change shape seasonally. In these settings, planning must allow for the seasonal shoreline adjustments, with structural treatments to manage longer-term shoreline trends used only to protect high-value assets and important cultural sites where alternative management responses are not possible. [ABSTRACT FROM AUTHOR]

Wu, T. and Qin, J., 2020. Influence of flow and sediment transport processes on sedimentation in groyne fields. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 304-308. Coconut Creek (Florida), ISSN 0749-0208. Groynes have been widely used to prevent coastal erosion worldwide. Various depositional patterns have been found in groyne fields, which are affected by flow and sediment transport processes. For a groyne field dominated by a single large gyre and sediment being mainly transported in the form of suspended load, the sediment deposition pattern is consistent with the gyre structure. For groyne fields showing complex flow structures or bedload-dominant sediment transport processes, the relationship between the deposition patterns and flow and sediment transport processes remains unclear. In this study, the deposition patterns of groyne fields formed by different flow and sediment transport processes were analysed based on flume experiments. The sediment deposition patterns as well as the bedload transport process in groyne fields were accurately measured. The distribution of flow characteristics was simulated using the Horizontal Large Eddy Simulation (HLES) of the Delft3d model. The results confirmed that the deposition patterns were affected by flow structures and sediment transport processes. For suspended sediment-dominated situations, the deposition patterns were consistent with the gyre structures. For bedload-dominated conditions, sediment deposition occurred where the bed shear stress fell below the critical shear stress. [ABSTRACT FROM AUTHOR]

Coastlines are vulnerable to the effects of climate change and sea-level rise as well as modifications in the wave climate and, in particular, increased storminess. The coastal areas of islands form part of this scenario and the Martinique shoreline illustrates this intensification of shoreline retreat and coastal erosion. In the context of this critical situation, a coastal observation network was set up in 2010 to monitor the evolution of the coast of Martinique. This network includes 28 beaches along the coast of Martinique and is based on studies of shoreline evolution using aerial photographs and topographic surveys of 71 cross-shore transects. The main aim of this network is to characterize the modal and seasonal dynamics of these vulnerable beaches and to estimate their resilience capacity and trends in the context of the increasing frequency of hurricanes. Analysis of the measurements over the last ten years highlights a general acceleration of the shoreline retreat. Furthermore, in terms of seasonal coastal evolution processes, the results clearly show the weak effect of the longshore sediment transport component on the open beaches of Martinique Island. However, a predominant cross-shore sediment transport component is observed on smaler bay beaches, which represent the most numerous beach type on the island (including several pocket beaches). On the short-term scale, the results of hydrodynamic and morphodynamic measurements highlight variable and intensive beach dynamic responses with a determining role played by shoreface parameters and coral-lagoon complexes. While cyclones have a significant impact on reducing the slope of beach profiles, our measurements reveal a significant resilience of eroded beaches owing to constructive swell. We also demonstrate that the hurricane season is not the season with the strongest morphosedimentary impacts. This almost ten-year-old observation network, provides an overview of shoreline evolution on Martinique and is an efficient management tool for the Lesser Antilles coastal environments. [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]

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]

Duy, D.V.; Tanaka, H.; Mitobe, Y.; Anh, N.Q.D., and Viet, N.T., 2018. Sand spit elongation and sediment balance at Cua Lo Inlet in Central Vietnam. In: Almar, R.; Almeida, L.P.; Trung Viet, N., and Sall, M. (eds.), Tropical Coastal and Estuarine Dynamics. Journal of Coastal Research, Special Issue No. 81, pp. 32–39. Coconut Creek (Florida), ISSN 0749-0208. Erosion is significant on the downdrift beach of Cua Lo Inlet, which is located in Central Vietnam. The elongation of Cua Lo Inlet's updrift sand spit together with severe erosion of the downdrift bank is raising numerous social problems such as flood safety and land loss. In this study, a series of Landsat and Google Earth images were used to analyze and investigate the inlet recent morphological changes and evolution. Since 1970 the inlet has constantly migrated towards the sediment transport pathway, and its traveling distance has reached 1700 m. In order to quantitatively investigate such characteristics, the tip coordinates and the area of the sand spit updrift of the inlet were calculated. In particular, the area of the sand spit has increased remarkably, and the increasing rate is almost constant. Using this value, the rate of sand volume transported along the updrift sand spit by the waves was estimated and it is in good agreement with the longshore sediment transport rate of the surrounding beach. [ABSTRACT FROM AUTHOR]

Appeaning Addo, K., 2018. Assessing ocean wave dynamics, potential sediment transport, and coastal erosion along Accra coast in Ghana. In: Almar, R.; Almeida, L.P.; Trung Viet, N., and Sall, M. (eds.), Tropical Coastal and Estuarine Dynamics. Journal of Coastal Research, Special Issue No. 81, pp. 76–85. Coconut Creek (Florida), ISSN 0749-0208. This study assessed wave dynamics and sediment transport along the coast of Accra in Ghana and compared the results with coastal erosion trend. Wave data from NOAA global wave model and measured buoy wave data were analysed as well as the potential sediment transport using the CERC's equation. The estimated mean significant wave height was 1.40 m and the period was between 10 and 15 seconds. The potential sediment transport rate was between 4.1 ×105 m3/yr and 4.1 ×105 m3/yr, while coastal erosion rate was 1.13 m/yr. Potential sediment transport rate increases from west to east. Coastal erosion is relatively high along the eastern and western coasts of Accra, while the central coast is relatively stable. Wave heights increased gradually from 1.00 m in January to a peak of 1.73 m in August, and eventually decreased to 1.10 m in December. The shape of the nearshore profile is significantly different along the eastern coast relative to the western and central coasts. This indicates that sediment transport intensity and nearshore bathymetry interaction in part explain the rate of erosion observed along the Accra coast in Ghana. [ABSTRACT FROM AUTHOR]

ABSTRACT Gómez, M.; Villagrán, M.; Martínez, C., and Belmonte, A., 2018. Characterizing the Longshore Sediment Transport Pattern on Beaches in the Gulf of Arauco, Chile, to Assess Morphological Shoreline Evolution. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 656–660. Coconut Creek (Florida), ISSN 0749-0208. Coastal evolution is an important research topic worldwide and has become increasingly relevant due to growing anthropogenic pressure on the coast and a climate change scenario (Masselink et al., 2016). The Gulf of Arauco covers an area of roughly 40,000 km2 and has a sandy-rocky coastline located in a very seismic environment. The area has suffered several major earthquakes during the last century (Valdivia 1960, Maule 2010) and seismic displacement has widely affected the coastline (Béjar-Pizarro et al., 2010). Despite these findings, the morphological evolution of sandy coastlines is mainly caused by wave-driven littoral processes. In this paper, using numerical modeling (Delft3D), we aim to characterize the longshore sediment transport (LST) direction at several spots (7 beaches) spread along the coastline of the Gulf of Arauco. Wave patterns were identified at each study site, revealing the importance of Santa Maria Island, located at the entrance to the gulf, despite the approach direction of deep water waves. The island acts as a moderator of wave patterns, softening the highly energetic swell that comes from the Antarctic Ocean and sorting the wave propagation inside the gulf. Moreover, LST patterns were characterized at each site for dominant wave conditions (SW swell and NW winter storms) and it was possible to explain how each condition has a different response at each spot, even under similar co-seismic displacements. Adaptation capabilities differ from site to site, suggesting a dynamic equilibrium of beaches in the area. [ABSTRACT FROM AUTHOR]

ABSTRACT Bastos, A.P.; Ponte Lira, C.; Calvão, J.; Catalão, J.; Andrade, C.; Pereira, A.J.; Taborda, R.; Rato, D.; Pinho, P., and Correia, O., 2018. UAV Derived Information Applied to the Morphological Study of Slow-changing Dune Systems. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 226–230. Coconut Creek (Florida), ISSN 0749-0208. São João da Caparica (Portugal) slow-growing dune system was investigated using field-based GPS and UAV surveying methods. Here, vegetation may preclude straightforward extraction of ground surface data from DSM and low sedimentation rates demand high accuracy. The approach used comprised acquisition of UAV-derived DSM and RGB orthomosaics at flight-heights of 30 and 60 m. Results were compared with DTM derived from traditional RTK-GPS ground surveys. Two methods (M1 and M2) where used to convert UAV-derived DSM into a DTM, both departing from supervised classification of land cover. In M1, vegetation areas are removed from the original DSM, which is then re-interpolated. M2 redefines elevation of pixels corresponding to vegetation by subtracting a mean height parameter defined for each vegetation class. It was found that DTM derived from UAV and RTK-GPS data exhibit errors in the same order of magnitude, regardless of the higher resolution of the former. M2 yielded the best compromise when considering deviations in both profile and surface analysis. M2 is strongly dependent on vegetation classification and on parametrization of the vertical correction affecting each vegetation class. UAV methodology presents the best cost-benefit ratio relative to traditional RTK-GPS surveys, providing additional image information (RGB orthomosaic) synchronous of the topographic data. [ABSTRACT FROM AUTHOR]

ABSTRACT Talavera, L.; Del Río, L.; Benavente, J.; Barbero, L., and López-Ramírez, J.A., 2018. UAS & SfM-based approach to Monitor Overwash Dynamics and Beach Evolution in a Sandy Spit. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 221–225. Coconut Creek (Florida), ISSN 0749-0208. The role of overwash processes is of great relevance in the long-term evolution of sandy barriers, and it can also affect coastal infrastructures in the short term. In this work, a 10-month monitoring program based on the use of Unmanned Aerial Systems (UAS) in combination with Structure from Motion (SfM) algorithms was performed in order to monitor morphological changes and ulterior evolution at Camposoto beach, an overwash-prone coastal spit located in SW Spain. This UAS&SfM approach allowed the reconstruction of 6 Digital Elevation Models (DEMs) of the area with high temporal and spatial resolutions (RMS vertical errors spanning from 5 to 8 cm). The morphological changes occurred were detected using Geomorphic Change Detection Software in ArcGIS, and they were correlated with the oceanographic conditions that prevailed during the analysed period. The results obtained provided insight into the response of the system against storm-induced overwash, which caused significant erosion/accretion patterns over a pre-existing washover fan, as well as the landward migration of the system. In addition, this methodology captured the progressive partial recovery of the system, which included onshore transport of sand, fore-beach accretion, and berm reconstruction. Despite the partial recovery observed, spring tides also triggered non-storm overwash in the area during fair-weather conditions, allowing to rethink the actual vulnerability state of the spit against rollover processes. [ABSTRACT FROM AUTHOR]

ABSTRACT Alonso, R.; Solari, S., and Teixeira, L., 2018. Erosion Problem on a Fluvial Beach. The Case Study of “La Concordia” in the Uruguay River. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 131–135. Coconut Creek (Florida), ISSN 0749-0208. A case study of beach erosion at “La Concordia” is presented. It is a fluvial beach located in the most downstream stretch of the Uruguay River. Despite it is a fluvial environment, the 10 km width that the river has in this zone allows for the generation of wind-waves that play an important role in the morphological processes that shape its sandy margins. This was initially proven by assessing the evolution of the coastline from satellite images and aerial photos, since the main change observed in the coastline is the expected one when groins are built on a sea coast. After that, the predominant influence of waves was confirmed by: 1) a good agreement between the geometry of the system (i.e. plan-shape and profiles) with the one predicted by formulations conceived from wave dominated marine environments, 2) a cross–section river flow velocity distribution, calculated for an historical maximum discharge, that shows that outside of the river channels velocities are lower than the critical expected for bottom sediment transport, 3) an estimation of the littoral transport in agreement with the historical coastline evolution. This verification supports the use of models and methods commonly employed in coastal engineering for the study of this type of fluvial beaches. In this case, the numerical model XBeach was used to simulate the response of the system to extreme events, in order to provide an input to a beach nourishment design. [ABSTRACT FROM AUTHOR]

Kim, M.; Lim, H.S.; Do, J.-D.; Kim, S.-S.; Lee, H.J., and Shim, J.-S., 2018. Variations of nearshore currents induced by seasonal waves in Haeundae. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1551–1555. Coconut Creek (Florida), ISSN 0749-0208. Haeundae, located on the southeastern coast of the Korean Peninsula, is a famous sand beach with a 1.6 km long, 70 m wide coastline. It suffers from wave-induced beach erosion in both summer and winter. For beach restoration, the Korean government has conducted beach nourishment (620,000 m3), and installed submerged breakwaters at both ends of the beach. Despite these efforts, the beach is still vulnerable to erosion caused by high waves. To understand beach erosion processes and sediment transport mechanisms, the government initiated an R&D project for the development of coastal erosion control technology since 2013. As part of the project, we have measured over three years of AWAC measurements at a water depth of 22 m and 1.8 km from the beach. Intensive measurements of wave, current, sediment transport near the surf-zone in summer and winter have been made using AWAC, VECTOR, and ADV with OBS. Analyses of nearshore currents induced by seasonal waves in the surf-zone have shown that cross-shore currents in summer are mainly induced by strong waves from the SSW or S that propagate to the beach due to wave breaking and shoaling effects on the reef near the beach. However, longshore currents in winter are induced by high waves from the E or ESE that propagate to the shoreline by diffraction at the east coastline. Eroded sand in summer returns along the beach by cross-shore and weak longshore currents induced by waves from the SSW or S. However, suspended sand in winter is moved to the west by strong longshore currents induced by waves from the E or ESE. Due to its pocket beach shape, beach erosion and sediment transport are caused by variations of nearshore currents induced by seasonal waves. [ABSTRACT FROM AUTHOR]

Lim, H.S.; Kim, M.; Do, J.-D.; Kim, S.-S.; Lee, H.J., and Kim, D.H., 2018. Variation of nearshore currents induced by seasonal waves in Haeundae. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 686–690. Coconut Creek (Florida), ISSN 0749-0208. Wave-induced currents at Anmok, located on the eastern coast of the Korean Peninsula, are one of the main causes of beach erosion related to high waves. Coastline changes induced by beach erosion and deposition are predominantly caused by sediment transport in the surf zone. This sediment transport is generated by wave-induced currents and depends on the wave height and direction. To understand beach erosion processes and the sediment transport mechanisms, field measurements of beach elevation and water depth were conducted for one month in winter 2015–2016. Using AWAC, ADP, VECTOR, and Aquadopp Profiler with OBS, intensive observations were made of waves, currents, and sediment transport in the surf zone. Wave and current variations were simultaneously analyzed at a water depth of approximately 18 m (W1) using long-term deployed AWAC data. Wave statistical analysis at station W1 shows that high waves from the NNE and NE are dominant in winter due to strong northeasterly winds from the NE. However, in summer, high waves coming from the NE and ENE are prevalent due to seasonal winds from the E and SE. By analyzing currents observed in the surf zone with waves, we found that a cross-shore current is generated by high waves, predominantly in winter, with incoming waves normal to the shoreline. Following the direction of incoming waves, longshore currents are separated into SE or NW directions depending on high waves come from the NNE or ENE, respectively. The variations of wave-induced currents caused by incoming wave height and direction accounts for the observed beach erosion and sediment transport, which in turn leads to beach cusp formation and crescentic sand bar migration during high wave periods. [ABSTRACT FROM AUTHOR]

Gómez, M.; Villagrán, M.; Martínez, C., and Belmonte, A., 2018. Characterizing the Longshore Sediment Transport Pattern on Beaches in the Gulf of Arauco, Chile, to Assess Morphological Shoreline Evolution. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 656–660. Coconut Creek (Florida), ISSN 0749-0208. Coastal evolution is an important research topic worldwide and has become increasingly relevant due to growing anthropogenic pressure on the coast and a climate change scenario (Masselink et al., 2016). The Gulf of Arauco covers an area of roughly 40,000 km2 and has a sandy-rocky coastline located in a very seismic environment. The area has suffered several major earthquakes during the last century (Valdivia 1960, Maule 2010) and seismic displacement has widely affected the coastline (Béjar-Pizarro et al., 2010). Despite these findings, the morphological evolution of sandy coastlines is mainly caused by wave-driven littoral processes. In this paper, using numerical modeling (Delft3D), we aim to characterize the longshore sediment transport (LST) direction at several spots (7 beaches) spread along the coastline of the Gulf of Arauco. Wave patterns were identified at each study site, revealing the importance of Santa Maria Island, located at the entrance to the gulf, despite the approach direction of deep water waves. The island acts as a moderator of wave patterns, softening the highly energetic swell that comes from the Antarctic Ocean and sorting the wave propagation inside the gulf. Moreover, LST patterns were characterized at each site for dominant wave conditions (SW swell and NW winter storms) and it was possible to explain how each condition has a different response at each spot, even under similar co-seismic displacements. Adaptation capabilities differ from site to site, suggesting a dynamic equilibrium of beaches in the area. [ABSTRACT FROM AUTHOR]

Do, K.; Shin, S.; Cox, D., and Yoo, J., 2018. An international comparison of drowning in South Korea. In: Shim, J.- S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 196–200. Coconut Creek (Florida), ISSN 0749-0208. Coastal sand dune system is important in the nearshore environment for sand supply, ecosystem, and hazard mitigation. In this study, a process-based morphological model was performed and the results were compared with large-scale laboratory experimental data. Two-dimensional large-scale laboratory experiments were conducted with 1:6 geometric scale in the large wave flume (104m (L) × 3.7 m (W) × 4.6 m (D)) of the Hinsdale Wave Research Laboratory at Oregon State University (Maddux et al, 2006). Several different wave conditions were used with different water levels in this experiment including pre-storm, storm, and post storm based on random wave time series by using TMA spectrum. The data set included cross-shore Wave heights, fluid velocities, and the profile changes of the beach and dune. The process based model, XBeach (Roelvink et al., 2009) was used to simulate the nearshore hydrodynamics and bed level change during storm wave condition. Several semi-empirical parameters were used in the XBeach model to predict morphodynamic process (Roelvink et al., 2009) and recently the updated parameters (WTI settings) were suggested based on the results of field observations. The present study ran the XBeach model by using both default and WTI settings and compared with the results from the experiments. The results showed that the model results with WTI settings showed good agreement with the measured beach profile while the model results with default settings over-predicted the offshore sediment transport and dune erosion. Especially, the wave skewness (facSk) and asymmetry (facAs) gave the highest contribution to predict dune erosion. [ABSTRACT FROM AUTHOR]

Chang, Y.S.; Huisman, B.; Boer, W., and Yoo, J., 2018. Hindcast of Long-term Shoreline Change due to Coastal Interventions at Namhangjin, Korea. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 201–205. Coconut Creek (Florida), ISSN 0749-0208. Namhangjin beach is protected by multiple submerged breakwaters (SBWs) which were built to protect the ~4 km long sandy beach. A coastline model (UNIBEST) was used to investigate the long term effect of the SBW structures on the beach. The model computes long-term shoreline changes due to coastal structures as a result of the strong longshore sediment transport gradients at the structures. Bathymetry data of the shoreface and nearshore profiles were obtained from a field survey, while wave conditions from offshore WAM hindcast (Wave Modeling Group) were transformed towards the nearshore with the Delft3D+SWAN modelling system. Local wave sheltering by the SBWs was included in the wave model. A situation with and without the SBWs was modelled. A rapid adjustment of the shoreline was observed in the model as a result of the wave conditions in the first two years. After that, the shoreline shape stabilized without significant changes both for the situation with and without SBWs. A smooth curved coastline shape was obtained in the model without SBWs, while the model with SBWs shows a similar overall shoreline shape with undulations of the shoreline shape behind the breakwaters. A similar undulating shoreline was observed in the Sept-2013 imagery at Namhangjin beach. The local accretion behind the SBWs may induce some erosion in the lee area of the SBWs, causing distortions of the shoreline shape. Most sediment accreted at the first SBW (i.e. the northern most SBW where alongshore transport from the North was trapped), while the coastline change rate gradually decreased towards the South. The effectiveness of the SBWs at the considered shoreline section for maintaining the shoreline is somewhat ambiguous as local areas with accretion or erosion are present with respect to the situation without the breakwaters. The results show that multiple SBWs need to be carefully designed to protect beaches as local distortions of the shoreline shape may be present directly downdrift from the structures. [ABSTRACT FROM AUTHOR]

Alonso, R.; Solari, S., and Teixeira, L., 2018. Erosion Problem on a Fluvial Beach. The Case Study of "La Concordia" in the Uruguay River. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 131–135. Coconut Creek (Florida), ISSN 0749-0208. A case study of beach erosion at "La Concordia" is presented. It is a fluvial beach located in the most downstream stretch of the Uruguay River. Despite it is a fluvial environment, the 10 km width that the river has in this zone allows for the generation of wind-waves that play an important role in the morphological processes that shape its sandy margins. This was initially proven by assessing the evolution of the coastline from satellite images and aerial photos, since the main change observed in the coastline is the expected one when groins are built on a sea coast. After that, the predominant influence of waves was confirmed by: 1) a good agreement between the geometry of the system (i.e. plan-shape and profiles) with the one predicted by formulations conceived from wave dominated marine environments, 2) a cross–section river flow velocity distribution, calculated for an historical maximum discharge, that shows that outside of the river channels velocities are lower than the critical expected for bottom sediment transport, 3) an estimation of the littoral transport in agreement with the historical coastline evolution. This verification supports the use of models and methods commonly employed in coastal engineering for the study of this type of fluvial beaches. In this case, the numerical model XBeach was used to simulate the response of the system to extreme events, in order to provide an input to a beach nourishment design. [ABSTRACT FROM AUTHOR]

Kong, J.; Pan, M.; Shen, C.; Hua, G., and Zhao, H., 2016. Analysis of the morphological changes and related sediment transport mechanisms of the Baisha Shoal in the Qiongzhou Strait, China. The morphological changes and evolutionary mechanism of the Baisha Shoal in the Qiongzhou Strait were investigated using various methods, including bathymetric chart comparisons, geomodeling, hydrodynamic modeling, and hydrologic statistical analysis. Water depths were extracted from digitized charts to explore the evolution of the Baisha Shoal and to quantitatively estimate the changes in the shoal area within the 5-m isobath. The grain-size trend analysis (GSTA) model was introduced to explain the features of bed sediment distribution and to analyze the sources of the sediment. Tidal flow models and wave models were adopted to simulate the tidal flows and wave fields around the Baisha Shoal and to reveal the sediment transport dynamics. Further comparisons based on a Mann-Kendall trend analysis and remote-sensing image data from different years were used to discuss the reason for the recent evolution of the Baisha Shoal. The results show that the formation of the Baisha Shoal was caused by the combined effects of reciprocating flow in the eastern and western directions and waves from the NE direction. However, in recent years, the Baisha Shoal has demonstrated an unsteady geomorphological state and is transitioning from a deposition-dominated state to an erosion-dominated state. Erosion has become most significant since 2004, as reflected in the shoal area within the 5-m isobath, which is decreasing by 0.732 km2/y. The analysis demonstrated that a reduction in sediment load and increased sand mining are the two most significant factors that are progressively altering the shoal morphology. If these issues cannot be resolved, the strong dynamic surroundings will aggravate the erosion of the Baisha Shoal. This study on the Baisha Shoal highlights the necessity of combining different approaches to better understand coastal evolutionary features, dynamic mechanisms, and evolutionary causes, as well as to guide future coastal protection engineering design. [ABSTRACT FROM AUTHOR]

Wang, J.; Liang, B.C.; Li, H.J.; Pan, X.Y.; Lee, D.Y., and Xu, Y., 2016. Swash motion driven by the bore and prediction of foreshore profile change. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 492-497. Coconut Creek (Florida), ISSN 0749-0208. The prediction of a swash zone bed profile resulting from complex hydrodynamic processes is a challenging task. A series of laboratory experiments at a 2D wave flume were carried out to investigate the evolution of foreshore profiles and sediment transport in the swash zone. The swash motions and the changes of foreshore profiles at the different stages of foreshore evolution were measured for 12 cases of different combinations of wave height, wave period and water level for two different initial beach slopes (1/5 and 1/15). From the evolution of foreshore profiles detected by side looking video cameras mounted to the glass wall of a 2D wave flume, the sediment transport rates were estimated precisely both in time and space using the 1-D sediment conservation equation. The characteristics of the instantaneous sediment flux of swash motion and feasibility of its prediction were discussed. The characteristics of the swash-averaged net sediment flux at different stages of beach evolution were investigated by detecting the detailed net flux at 2 minute intervals from the precise beach profile changes. Simple methods of prediction of sediment transport and foreshore profile change are discussed for swash motion driven by bores. [ABSTRACT FROM AUTHOR]

Zăinescu, I.F.; Vespremeanu-Stroe, A. and Tătui, F., 2016. Comparative spit dynamics. The case of deltaic river mouth spits. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 800-804. Coconut Creek (Florida), ISSN 0749-0208. This paper presents a comparison of evolution and dynamics of selected representative deltaic spits. Although recently receiving more attention, deltaic barrier spits still remain poorly understood in terms of long term evolution. Water, sediment and wave interactions at the river mouth are highly nonlinear such that hydrodynamic groin effects and sediment trapping mechanisms generate behaviours such as cyclic lobe progradation, as it is the case of some deltaic lobes, or conversely impose river mouth deflection when the wave influence becomes dominant. River mouth spits can be part of a prograding lobe ( e.g. Sacalin and the paleo-spits of the Danube Delta lobes, Ba Lat spits) or can be a sign of lobe abandonment due to lobe switching, geoengineering or extreme reduction in sediment supply ( e.g. La Banya, Ebro; Gracieuse, Rhone; Damietta, Nile). Human-induced reductions in river solid discharge have affected the majority of Mediterranean deltas and there is a wealth of other examples worldwide ( e.g. Krishna & Godawari deltas). Dependent on the wave climate and especially the wave direction, cuspate features, migrating sand waves or flying spits form at the downdrift side of lobes. Comparison of dynamics shows that spits experience high temporal (inter-decadal), spatial (alongshore) and inter-landform variability. Dynamics is complex, often resulting from different interrelating effects which importance in control can change over time. [ABSTRACT FROM AUTHOR]

Haghshenas, S.A.; Razavi A., A.; Bakhtiari, A., Jedari Attari, M., and Risk, M.J., 2016. Decadal Evolution of Mond River Delta, the Persian Gulf. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 805-809. Coconut Creek (Florida), ISSN 0749-0208. This paper studies the results of multi-disciplinary investigations on different features of evolution of the Mond River delta during the past five decades. Considering the high importance of Mond River and corresponding sediment discharge, physiography and watershed analysis of Mond River is investigated and sediment discharge from the river and its sand content are estimated in the first step. A numerical model has been utilized to investigate cases of flow and sediment transport behaviour in the coastal Mond area and annual rates of longshore sediment transport are estimated. The shoreline changes are investigated by analysing thirty four sets of aerial photos and satellite imagery taken between 1967 and 2014 to investigate decadal evolution of Mond River Delta during the past three decades. Eventually, numerical results are compared with field observations and comprehensive GIS based analysis of historic shoreline changes from aerial photos and satellite imagery. [ABSTRACT FROM AUTHOR]

Lim, H.S.; Chun, I.; Shim, J.S., and Kim, C.S., 2016. Wave-induced current simulated by wave-current coupled model in Haeundae. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 1392 - 1396. Coconut Creek (Florida), ISSN 0749-0208. The wave-induced current in Haeundae, at the southeastern end of the Korean Peninsula, is one of the main causes of beach erosion. The Korean government recently initiated a beach restoration project for Haeundae beach to protect the famous beach against wave-induced currents generated by waves during summer and winter. To mitigate beach erosion, two submerged breakwaters and a sand nourishment program were initiated in 2013. With the support of the Korean government, we have also started an R&D project to develop coastal erosion control technology in order to understand the processes of beach erosion by measuring sediment transport and hydrodynamics in Haeundae coastal waters, including the development of a numerical simulation method. The aim of this study is to understand the main processes of wave-induced currents that cause erosion at Haeundae beach by considering wave and tide interactions, using a wave-current coupled model compared with long-term observed wave and current data. We found that the cross-shore current during summer is mainly caused by the eddies produced by wave-induced currents generated by strong high waves during a Typhoon approaching from the SSW and S directions. During other seasons, a longshore current is produced by swell waves coming from the E and ESE directions. In comparisons with the measured data, we also found that the wave-induced current is well simulated by a wave-tide coupled model in Haeundae with a coastal environment of wave and tide interaction. [ABSTRACT FROM AUTHOR]

Saravanan, S. and Chandrasekar, N., 2015. Wave refraction pattern and littoral sediment transport along the SE Tamilnadu coast, India. The objective of the paper is to understand the wave refraction pattern and littoral sediment transport along the SE coast of India. There are areas of erosion and accretion observed along the coastal stretch that depend primarily the direction of wave approach, the wave period, and the wave refraction pattern. In the nearshore zone of the study area, the movement of sand alongshore is due to the action of waves and currents. Wave refraction is an important process responsible for effecting changes in coastal configuration. Based on this study, the wave convergent and divergent zones are identified with reference to wave refraction. Longshore sediment transport is higher in the northerly direction than in the southerly direction. The present study of littoral sediment transport implies that the beaches of Kanyakumari, Navaladi, and Ovari have greater transport rates. [ABSTRACT FROM AUTHOR]

Kaiser, M.F., 2014. Disturbance of hydrodynamic regime in the Mediterranean coastal zone of Egypt. Engineering structures induce variations in the physical parameters of incident waves approaching coastlines, affecting the rate of longshore sediment transport and the patterns of shoreline change. Landsat Thematic Mapper images acquired from 1990 to 2005 and field measurements were utilized to perform mathematical modeling along Mediterranean coastal zones in Egypt. The K1 transport coefficient values used to calibrate the models ranged from 0.05 to 0.9. To accommodate changes in the physical conditions, a second calibration was required. The K1 transport coefficient values determined by the second calibration ranged from 0.1 to 0.7. These results indicate that the hydrodynamic regime along the Nile Delta coastal zones during 1995-2000 (verification) and 2000-2005 (second calibration) was disturbed by the effect of engineering works. Therefore, the calibration parameters used in simulations before 1995 are not appropriate for use after 1995. These findings demonstrate how the physical parameters of waves and currents are disturbed after some protective structures are modified. [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]

Lim, H.S.; Kim, C.S.; Lee, H.J.; Shim, J.S.; Kim, S.J; Park, K.S., and Chun, I., 2014. Variability of residual currents and waves in Haeundae using long-term observed AWAC data. The Haeundae in the southeastern Korean Peninsula is a famous beach which is one of the most popular tourist attractions of Korea in summer. It is about 1.6 km long and 40 m wide facing the southeastern sea of Korea and Korea Strait. During strong winds in winter and severe typhoons in summer, the beach is significantly eroded by waves and nearshore currents in the surf zone. The intensive coastal developments during last 30 years have caused substantial beach erosion and bathymetric changes in the nearshore area, despite various beach restoration projects, including beach nourishments. Recently, the government decided to construct two submerged breakwaters near both ends of the beach to enhance the preservation potential of the beach replenishments. We estimated the seasonal variations in residual currents from one-year flow measurements using the Acoustic Wave and Current (AWAC) meter, at two locations of Haeundae at approximately 15 m and 22 m in depths. Short-term flows were measured in the surf zone during summer and winter. The moving average method was applied fortnightly to estimate the residual currents. In addition, waves measured with the AWAC were analyzed to characterize seasonal variations in the beach environment of Haeundae. The observed residual currents were well matched with the simulated counterpart from a wave and current coupled model. These simulated nearshore currents appear well correlated with seasonal variations in beach erosion and accumulation. The wave and current data were also used to validate an operational coastal modeling system for the prediction of hydrodynamics. These observations will be incorporated in simulations of sediment transport in Haeundae coastal waters for developing coastal erosion control system. [ABSTRACT FROM AUTHOR]

Martínez, R.; Silva, R., and Mendoza, E., 2014. Identification of coastal erosion causes in Matanchén Bay, San Blas, Nayarit, Mexico. This work presents an analysis of the erosion processes in Matanchén Bay based on the available historical records; the possible causes were identified and discussed. The bay is located on the Pacific coast of Nayarit state, Mexico; its northern tip is a highly dynamic system that has undergone intense morphological modifications over the last 80 years. At the beginning of the 1940s an unexplained growth in the beach at the northern tip of the bay was observed, while 40 years later, and up to date, erosion processes began adversely affecting small businesses in the area. The primary causes of the erosion are the anthropogenic modifications in the bay and its surroundings, which include the construction of a hydroelectric dam system, new transport infrastructure, tourist facilities, a harbor and several dredging works in the existing port. In this paper the evolution of the coastline at Matanchén Bay and its surroundings is analyzed for the first time and the actual coastline is compared to that predicted under the assumption that no countermeasures against the erosion are adopted. [ABSTRACT FROM AUTHOR]

Alonso, R.; López, G.; Mosquera, R.; Solari, S., and Teixeira, L., 2014. Coastal erosion in Balneario Solís, Uruguay. Balneario Solís is a seaside resort located in Uruguay, on the northern coast of the outer Río de la Plata estuary. Its main beach has suffered an erosion process that has affected the cliffs, producing a retreat of approximately 35 m between 1980 and 2001. Nowadays, some buildings are at risk of collapse and tourism has been seriously affected. Aerial photo analysis shows a temporal coincidence between the beginning of the erosion process and a change in the growing direction of a sandspit located next to the beach. Assuming the later as a geomorphologic indicator of the net littoral transport, the erosion process was linked to littoral transport change. No human factors were clearly identified to explain this change. Therefore, two hypotheses were formulated and analyzed: climate variability and natural modifications of the bathymetry in the outer zone of the beach. Finally, beach nourishment is proposed in order to restore the beach and protect the cliffs, and some questions are formulated for guiding future works in the site. [ABSTRACT FROM AUTHOR]

Ahmed, M.T.T.; Sato, S., and Tajima, Y., 2014. Quantitative estimation of longshore sediment transport based on thermoluminescence: two case studies around Tenryu and Nile River mouths. Longshore sediment transport (LST) is one of the key factors determining coastal deformation. Appropriate understanding of LST is thus essential to sustain coastal management and propose efficient countermeasures. However, it is quite difficult to quantify LST where detailed information of waves and bathymetries is not available. This study provides a novel methodology for quantitative estimation of LST by utilizing the residual thermoluminescence (TL) properties of feldspar grains. A newly proposed TL-based system estimates LST as a function of alongshore distributions of TL and dominant wave heights at the study sites. This study first analyzed and developed the TL-based bleaching curves due to sun exposure of the 180-300 μm fraction of feldspar grains from three different regions: Egypt, Japan, and Sri Lanka. On the basis of the obtained bleaching curves, the spatial distribution of TL along the coast was estimated, and the alongshore slope of TL decay was compared with the locally estimated average longshore current velocity, mixing sand layers, and moving sand volume, all of which were subsequently linked to LST. The newly proposed methodology was applied to two coastal areas around the Tenryu River and Nile River mouths, and it was found that the proposed methodology is capable of estimating directions and amount of LST around river mouths where sand with high TL is discharged continuously. [ABSTRACT FROM AUTHOR]

Randazzo, G., Cigala, C., Crupi, A., Lanza, S., 2014. The natural causes of shoreline evolution of Capo Peloro, the northernmost point of Sicily (Italy). In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 199-204, ISSN 0749-0208. During recent times, the world's coastline has been constantly changing, and factors such as: the absence of sediment transport from rivers, urbanization of the coastal zone, construction of protective structures and ports, contribute to such change. An increase in frequency and intensity of storm events may also play a role. In the area of Capo Peloro (eastern Sicily) in the last 180 years, the changing coastline has been assessed using maps, aerial photographs, urban plans, historical notes, and surveys from 1824 to 2013 with the support of a long winded dataset series (1951 to 2012). The area of Capo Peloro is the northernmost headland of Sicily, dividing the Tyrrhenian from the Ionian Sea and stretching into the Strait of Messina. The four beaches which constitute the continuous coastal system of the cape show rapid evolution. Analysis of the wind records shows a decreasing trend for winds coming from the orientation range of 290°-330°, while there is an increasing trend for those coming from the range of 331°-20° and, in general, wind intensity has increased in the last 9 years. Comparison of the coastal evolution pattern and the wind data set, a direct relationship has been recognized, while urbanization has not affected this trend. The beach of Tiro a Volo lost its capability to regenerate and protect itself naturally in 2012, which was the windiest year of the series considered. Erosion in 2012 uncovered old anthropic structures, eliminating the morphological connection between the beach and the alluvial plain. The hardening of the landward limit of the beach caused a loss of beach resilience. Due to the exposed structures, an artificial redistribution of the sedimentary material in the area is now necessary. [ABSTRACT FROM AUTHOR]

Araújo, M.A.V.C., Di Bona, S., Trigo-Teixeira, A., 2014. Impact of detached breakwaters on shoreline evolution: a case study on the Portuguese west coast. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 041-046, ISSN 0749-0208. The Portuguese West Coast is facing severe erosion problems that threaten both the population andthe immediate seaside properties. Some locations, such as the Vagueira region, are especially vulnerable. In an attempt to reverse the present erosional trend, a coastal defense scheme involving two detached breakwaters was introduced in a phased manner. In this work, the impact of those two detached breakwaters on the down-drift coast is investigated. The study area extends from south of the Costa Nova village southwards to Mira. The shoreline evolution is predicted, for various decades, using the GENESIS model. The present time shoreline position, from which future situations are predicted, was obtained using LIDAR data acquired in 2011. Two different future scenarios are investigated: the 'do-nothing' scenario, which assumes that no further engineering interventions will be performed on the coast; and the 'detached breakwaters protected' scenario, with the first breakwater introduced in 2011 and the second in 2026. Depending on sediment supply, two types of simulations are carried out: calibrated simulations, which assume that the amount of sediments in the future will be equal to those in the present situation; and extreme simulations, which assume an acute shortage in sediment supply. Results show that if no further interventions are executed at the Vagueira region, the entire coastal stretch will continue to erode, which could lead to extreme consequences in some locations, depending on sediment supply. If two detached breakwaters are introduced at different intervals, a new accreting trend is predicted at the Vagueira region, reversing the present erosional phase. However, the erosional trend will continue southwards, unless a 3rd detached breakwater is introduced in Mira. [ABSTRACT FROM AUTHOR]

Biancini da Silva, A., Barboza, E.G., Rosa, M.L.C.C., Dillenburg, S.R., 2014. Meandering Fluvial System Influencing the Evolution of a Holocene Regressive Barrier in Southern Brazil. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 205-210, ISSN 0749-0208. A meandering fluvial system changes its course according to geological time, eroding rocks and pre-existing deposits and transporting large volumes of sediment to the coastal plains. Understanding the evolution of channels and paleochannels in regions showing coastal barriers and relating them to changes in sea level becomes extremely important to comprehend the factors that contribute to the behavior of coastal barriers. During the Holocene the barrier at Passo de Torres located northeast of the Mampituba River, along the southern coast of Santa Catarina state, prograded approximately 5.5 km. The barrier comprises both foredune ridges, which occur in the landward portion, and transgressive dune ridges, which occur seawards. One feature that stands out in the region is that the regressive barrier morphologies are truncated (eroded) by paleochannels and channels of a meandering fluvial system, which can be related to the dynamics of the Mampituba River. These paleochannels have elongated morphologies with SW - NE orientation and are up to 25 km long. With the purpose of characterizing the longer paleochannels, the geophysical method of ground penetrating radar (GPR) was used, associated with drill hole and radiocarbon dating. The GPR profile reveals continuous reflectors (± 5 m depth) with great contrast and lateral continuity for over 450 m. These represent an erosive surface, interpreted as the base of the fluvial channel. The granulometric results indicate that around 5 m, an increase in grain size (fine sand grading to medium sand) and the presence of several shells. These are very fragmented, characterizing a probable bedload transport. However, shells of the genus Donax sp. were collected intact with no signs of abrasion. This genus inhabits beach environments (specifically foreshore) and cannot survive in freshwater environments. These shells were incorporated to the bedload of the fluvial channel through an inlet, probably during storm surge events. These events carried beach sands, associated with shells (mainly Donax sp.), towards the continent, which were incorporated into the fluvial sediments. The dating of these species revealed an age between 5.6 - 5.4 cal ka. The ages obtained are consistent with the maximum sea level of the Postglacial Marine Transgression (PMT) in southern Brazil. Because these shells are exclusive to beach environments, dating allowed us to infer that this channel was active and had connection with the ocean at about 5.5 ka, concomitant with the maximum sea level of PMT. [ABSTRACT FROM AUTHOR]

Tõnisson, H., Suursaar, Ü., Kont, A., Orviku, K., Rivis, R., Szava-Kovats, R. Vilumaa, K., Aarna, T., Eelsalu, M., Pindsoo, K., Palginõmm, V., Ratas, U. 2014. Field experiments with different fractions of painted sediments for studying material transport in three coastal study sites in Estonia. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 229-234, ISSN 0749-0208. Our current understanding of the morphodynamics in swash and surf zones is limited due to their turbulent and irregular nature. The importance of this zone to sediment transport led us to perform a sophisticated field experiment using painted sediments. Sediments collected locally from beach ridges were sorted into the following diameters: 1-2 5 cm, 2.5-5 cm and 5-10 cm. The sediments were painted, amassed in piles and placed at 0.5-10 m depths in three sites near the Estonian coast. The locations were recorded with GPS devices and photographed. The sediment piles placed in the sea were monitored at least once after an intense storm or once before and after the storm season. Some sediments were placed on the shoreline and monitored daily for a shorter period. Hydrodynamic parameters were also measured or hindcasted during the experiment. We found that wave breaking during storms can take place even at 6 m depth, but mostly between 2-4 m depth. Sediment fractions between 1-10 cm diameters can be transported over 20 m towards the shore. Even sediment piles at 10 m depth were moved 2-4 m, but towards the open sea. Sediments accumulated on the shoreline moved up to 3 m/hour along the shore and approximately 350 m during three months. We also found that calm periods can be more influential in places where regular vessel-generated waves wash the shores. As vessel-generated waves often approach from a different angle than natural waves, they can cause notable erosion during the periods when natural waves are weak or absent. [ABSTRACT FROM AUTHOR]

Larnier, S., Almar, R., Cienfuegos, R., Lejay, A., 2014. On the use of the Radon transform to estimate longshore currents from video imagery. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 023-028, ISSN 0749-0208. In nearshore applications, the estimation of longshore currents is of primary importance since it controls the alongshore sediment transport and coastal evolution. Direct estimation of longshore currents using in-situ instruments is difficult and costly, especially under highly energetic wave climates. Low cost remote sensing systems based on video observations constitute a promising alternative when the drifting sea foam left after the passage of breaking waves is visible. In this paper we describe a method based on longshore timestacks that necessitates less data than approaches using the full video frames. Our approach uses the Radon transform applied on the time series derived from timestacks to produce an estimate of the longshore component of nearshore surface currents detected from the foam signature in video images. The Radon transform can be used to separate the wave crests from the drifting foam part. The identification of the longshore drift is enhanced with both a temporal and a spatial filters. The corresponding sinogram from the Radon transform is computed in order to find the angle of the alongshore drifting that is further converted into the longshore component of the surface currents. For the estimation of longshore currents, our approach is first tested using synthetic timestack examples created using anisotropic Gaussian random current fields. Comparisons between estimates derived by our algorithm and manual operator detection from videos are performed showing good agreement. These videos come from a field campaign conducted in the Mataquito River mouth area in the Maule region (Chile). Field test comparisons were also made against in situ current meter from the 2008 Truc Vert experiment in Aquitaine (France). It was taking place during an energetic event. [ABSTRACT FROM AUTHOR]

Laïbi, R. A., Anthony, E. J., Almar, N., Castelle, B., Senechal, Kestenare, E., 2014. Longshore drift cell development on the human-impacted Bight of Benin sand barrier coast, West Africa. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 078-083, ISSN 0749-0208. The Bight of Benin is an open, microtidal, wave-dominated coast forming a 500 km-long mild embayment in the Gulf of Guinea, in West Africa, between the Volta River delta in Ghana, to the west, and the western confines of the Niger River delta in Nigeria to the east. The bight is exposed to energetic swells from the South Atlantic, and is characterised by Holocene sand barriers bounding lagoons. The barrier system has been sourced essentially by sand supplied through the Volta River delta, terminus of a large river catchment of 397,000 km2, although wave energy conditions and sand mineralogy also suggest inputs from the nearshore shelf. The long-term pattern of barrier progradation in the Bight of Benin culminated in a mildly embayed coast wherein incident wave behaviour, beachface gradient and the longshore sand transport system were intimately linked, generating what may be classified as an 'equilibrium drift-aligned' coast with a unique and homogeneous longshore drift cell stretching from the Volta River delta to the Niger River delta. This coast has, however, been significantly impacted over the last 50 years by the construction of three deepwater ports in Lomé (Togo), Cotonou (Benin) and Lagos (Nigeria) that have intercepted sand supply, as well as by a major dam on the Volta River, resulting in destabilization of the former single drift cell on this coast. The ensuing multi-cellular structure is characterised by long sectors of rampant coastal erosion that threatens parts of these cities, coastal villages and infrastructure. [ABSTRACT FROM AUTHOR]

Burningham, H., French, J.R., 2014. Travelling forelands: complexities in drift and migration patterns. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 102-108, ISSN 0749-0208. Cuspate forelands have been described from a range of shorelines around the world, but in the majority of cases, the foreland maintains a constant position relative to the neighbouring shoreline. Here, we describe the contemporary geomorphology and historical evolution of a small cuspate foreland on the Suffolk coast, UK, which has been migrating northward for several centuries. Benacre Ness, a mixed sand and gravel sedimentary accumulation, is currently located at Kessingland, 5 km to the north of Benacre, from which it gained its name when adjacent to it in the 19th century. The foreland was previously called Covehithe Ness, having been adjacent to Covehithe (3 km south of Benacre) early in the 19th century. Previous sediment transport experiments and modelling studies have demonstrated a net southerly transport direction on this coastline, yet the foreland has continued to migrate northward over several centuries. Local reversals in sediment transport direction and rates are likely responsible for the northward migration of the foreland, but substantial changes in behaviour over the last 400 years suggest a close relationship between foreland dynamics and coastal configuration. [ABSTRACT FROM AUTHOR]

Smith, A.M., Guastella, L.A., Goble, B.J., 2014. Forecasting lagoon outlet erosion: KwaZulu-Natal, southeast Africa. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 151-156, ISSN 0749-0208. The Amanzimtoti Lagoon is at the mouth of the Amanzimtoti River. The lagoon outlet changes systematically in response to the 18 year long Dyer-Tyson summer rainfall cycle (DTC). During the dry part of the DTC the lagoon is generally closed, opening only during heavy rainstorms. When closed the lagoon is separated from the sea by a baymouth bar, varying from 30 to 60 m wide. The open-days per year have increased dramatically as the DTC has entered the wet phase. Early in the DTC the lagoon rarely opened, and when this occurred it breached near the centre of the headland bound bay, but as the DTC-driven runoff cycle has progressed the outlet has remained open. However, during this open phase the outlet has been forced southward along the back beach until it deflected seaward by the southern headland outcrop. This appears to be brought about by longshore drift and an increased beach width. We suggest that this is due to the shoreward reworking of sediment by waves. This sediment has been brought down by the river in increasing amounts as the wet part of the DTC waxes, strengthening the seasonal rainfall and the river flow cycle. Wave reworking has forced the outlet along the back beach causing erosion of the coastal dune behind the back beach. Thus, the lagoon mouth enters a predictable erosion phase as the DTC progresses. This cyclicity can be used to forecast this type of lagoon outlet erosion. The Amanzimtoti Lagoon has strong similarities to the Hapua Lagoon-type recognized from New Zealand. [ABSTRACT FROM AUTHOR]

Idier, D., Castelle, B., Charles, E. and Mallet, C., 2013. Longshore sediment hindcast: spatio-temporal variability along the SW Atlantic coast of France ! The Aquitanian coast (SW France) is exposed to high-energy waves, and subject to an overall shoreline erosion of 1 to 3 m/year. Engineering practices in this area requires the knowledge of longshore sediment fluxes. The reference values of direction and variability have been estimated 33 years ago with data available at that time. More recent estimations have been done on limited area and time span. The present study aims at: (1) updating and discussing the longshore sediment flux on this coast, (2) comparing the longshore drift spatial variability with measured shoreline evolution, (3) analyzing the interannual variability, in comparison with NAO indexes. Using a recent wave hindcast spanning the period 1958-2001, and the Kamphuis (1991) formula, the obtained gradients in longshore drift appear roughly consistent with the shoreline evolution and previous estimations of residual sediment fluxes. However, the estimated northward oriented fluxes are smaller in the present study than in the 33 year old reference study. The analysis shows a strong interannual variability, slightly smaller than the longshore variability. The interannual variability is not uniform along the coast. The northern section seems to be correlated with NAO indexes. Further analyses are required to better understand the temporal variability of the longshore sediment fluxes. [ABSTRACT FROM AUTHOR]

Pereira, C., Coelho, C., Ribeiro, A., Fortunato, A., Lopes, C.L. and Dias, J.M., 2013. Numerical modelling of shoreline evolution in the Aveiro coast, Portugal - climate change scenarios In the Northwest coast of Portugal, the shoreline evolution is leading to several problems, such as loss of territory and infrastructural damages, mainly caused by the sea wave's action. This study aims to predict the impacts of climate change on the shoreline evolution in this coastal area. Coastal stretches studied were Esmoriz-Furadouro and Vagueira-Mira, due to their vulnerability related with the low lying sandy coast, the deficit of sediments, the presence of urban waterfronts and the narrow width of the sand spit that separates the ocean from the Aveiro lagoon. The paper describes the application of two shoreline evolution models (LTC and GENESIS) to the projection of shoreline evolution between 2010 and 2100. A reference scenario considering the present typical wave climate and the mean sea water level was compared with 3 other future scenarios that may result from climate change effects, combining different wave climates and mean sea levels (0.42 and 0.64 m above present level). Considering the numerical models' results, maps of the shoreline position were represented every 30 years. The results allowed the analysis of the shoreline retreat, the areas of lost territory and the alongshore sediment transport volumes in several cross sections. A strong trend of shoreline retreat was found for all the scenarios, although the retreat rates tend to decrease along time. Comparing the reference scenario with the climate change scenarios, a slight clockwise rotation of the shoreline was predicted, also increasing the average shoreline retreat from 6% to 11%, depending on the considered scenario. [ABSTRACT FROM AUTHOR]

Costa, S. and Coelho, C., 2013. Northwest coast of Portugal Past - behavior and future coastal defense options Portugal's northwest coast, between Ovar and Marinha Grande presents an important sediment deficit, mainly due to rivers sediments supply reduction and harbors' constrains. The sediment transport capacity resulting from the wave's action (mainly from the northwest) is nourished with the sand of the up drift beaches, leading to the shoreline's erosion and retreat. The shoreline retreat represents conflicts with the land use and human occupation, and the protection of people and properties becomes essential. Thus, coastal interventions (seawalls and groins), try to constrain the shoreline evolution, conducting to an artificial coast and site aesthetical deterioration. This work's objective is to present an analysis of the shoreline evolution, in order to select a suitable model of coastal intervention. Thus, the current paper aimed a diagnostic based in the shoreline evolution indicators in the period between 1994-2011: a) average rate of shoreline retreat; b) number of coastal defense structures implemented; c) number of coastal emergency works and interventions; and d) number of registered events related to shoreline retreat (overtopping, dune system and coastal structures partial destruction). This analysis highlights the location of the most vulnerable areas. Furthermore, different scenarios of coastal defense interventions are discussed, having as variable the associated investment costs, which represents different strategies and impacts, namely: a) maintain the existent coastal defense structures; b) adapt the existent coastal defense structures; c) perform artificial nourishments; and d) propose new coastal defense solutions. [ABSTRACT FROM AUTHOR]

Garcin, M., Baills. A., Le Cozannet, G., Bulteau, T., Auboin, A-L., Sauter, J., 2013. Pluri-decadal impact of mining activities on coastline mobility of estuaries of New Caledonia (South Pacific) This work aims at analysing the relative impact of sedimentary supply by rivers versus the effect of sea level rise and other processes over the last 5 decades of some representative coastal stretches of New Caledonia (South Pacific Ocean). The study of twelve coastal estuarine stretches has shown erosion rates ranging from −1.8m/y to accretion rates up to 5.5m/y over the last 50 years. During this time, the climate component of sea level rise has been evaluated around 0.5mm/y in Nouméa and can be considered identical on the studied island. Vertical movements affecting New Caledonia are suspected to be different between western and eastern parts of the island. Nevertheless, in areas with homogeneous vertical movement, the coastal stretches studied show various evolution rates. The analysis of accreting estuarine coastal areas shows that this evolution is linked to sedimentary supply from rivers. On New Caledonia Island, the creation of bare soils by nickel mining during the last 50 years has increased erosion processes on the watersheds and the solid discharge of the rivers. The study shows a strong correlation between the percentage of bare soil surfaces (up to 3.7 % of the watershed surface) generated by nickel mining and the coastline evolution rate (from −2m/y to +4m/y) around the estuaries of each watershed. Therefore, mining activity on watersheds is suspected to have been the major forcing factor of recent coastal changes during the last fifty years. [ABSTRACT FROM AUTHOR]

Ganesh, R. and Gopaul, N., 2013. A Predictive Outlook of Coastal Erosion on a Log-Spiral Bay (Trinidad) by Wave and Sediment Transport Modelling Coastal erosion is increasingly becoming a significant concern (economic and recreational) on considerable stretches of Trinidad's coastlines. Modelling investigations were undertaken into the impacts of time varying wave climates on coastal stability issues on Guayaguayare Bay, SE Trinidad. Erosion is currently occurring at an approximate rate of 0.6m per year (8-yr average). By utilising a wave dataset of approximately 5 years collected at both offshore and nearshore locations, a good appreciation into incoming wave energy was gained. Wave transformation modelling was carried out using DHI's MIKE21 SW. Increases in wave energy were found to be directly influenced by the North Atlantic winter storm period. Therefore, some variance in erosion rates, at different times of the year exists. Sediment transport across the bay was investigated using MIKE21 ST and LITDRIFT to determine volume variations. By using MIKE21 SW, transformed wave parameters at the shoreline were accurately obtained. Certain high risk zones were therefore identified as related to on-going coastal erosion. An insight into the seasonality of sediment transport processes (wave driven) taking place along this bay is now better understood but given a longer dataset more accurate quantifications can be made. Finally, net erosion/accretion zones were identified which can aid the coastal engineer/manager in making future infrastrucutural development decisions. [ABSTRACT FROM AUTHOR]

Sediment budget analyses along the south shore of Fire Island, New York, have been conducted and debated in the scientific and coastal engineering literature for decades. It is well documented that a primary component of sediment transport in this system is directed alongshore from E to W, but discrepancies in volumetric sediment budget calculations remain. An additional quantity of sand, averaging about 200,000 m3/y is required to explain the growth of the western segment of the barrier island, a prograding spit. Littoral sediment derived from updrift erosion of the coast, addition of beach nourishment fill, and onshore transport of inner continental shelf, shoreface sediments, or both have all been proposed as potential sources of the additional sediment needed to balance the sediment budget deficit. Analysis of highresolution seafloor mapping data collected in 2011, including seismic reflection profiles and inteferometric sonar acoustic backscatter and swath bathymetry; comparison with seafloor mapping data collected in 1996-1997; and shoreline change analysis from 1933 to 2011 support previous suggestions that the inner-shelf Holocene sedimentary deposit is a likely source to resolve this sediment budget discrepancy. [ABSTRACT FROM AUTHOR]

Historical shoreline and bathymetric survey data were compiled for the barrier islands and passes fronting Mississippi Sound to identify net littoral sand transport pathways, quantify the magnitude of net sand transport, and develop an operational sediment budget spanning a 90-year period. Net littoral sand transport along the islands and passes is primarily unidirectional (east-to-west). Beach erosion along the east side of each island and sand spit deposition to the west result in an average sand flux of about 400,000 cy/yr (305,000 m³/yr) throughout the barrier island system. Dog Keys Pass, located updrift of East Ship Island, is the only inlet acting as a net sediment sink. It also is the widest pass in the system (about 10 km) and has two active channels and ebb shoals. As such, a deficit of sand exists along East Ship Island. Littoral sand transport decreases rapidly along West Ship Island, where exchange of sand between islands terminates because of wave sheltering from the Chandeleur Islands and shoals at the eastern margin of the St. Bernard delta complex, Louisiana. These data were used to assist with design of a large island restoration project along Ship Island. Mississippi. [ABSTRACT FROM AUTHOR]