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Stalter, R. and Lonard, R.I., 2024. Biological flora of sand dunes on the northwest Pacific coastline of North America: Ammophila arenaria (L.) Link and Ammophila breviligulata Fernald. Journal of Coastal Research, 40(5), 994–1000. Charlotte (North Carolina), ISSN 0749-0208. Ammophila arenaria, native to European coastal dunes, was initially introduced on the Pacific coast of North America in 1868, while A. breviligulata was introduced to temperate regions along the Pacific coast in 1935. Both rhizomatous taxa are often dominant on coastal foredunes. Ammophila arenaria has short, thick rhizomes, while A. breviligulata has a spreading rhizome system. Both species have been introduced for sand stabilization and shoreline protection. The primary method of reproduction for both taxa is fragmentation of rhizomes. Ammophila breviligulata aggressively competes with A. arenaria and is now dominant over A. arenaria at many sites. The introduction of A. arenaria and A. breviligulata has contributed to dense cover on foredunes and a concomitant decline of native plants and animals, especially those dependent on open sand habitats. Ammophila breviligulata successfully competes with A. arenaria, which has reduced dune heights, increasing the number of areas vulnerable to storm surges and dune erosion. [ABSTRACT FROM AUTHOR]

Belrhaba, T.; Hakkou, M.; Rey, T.; Aangri, A.; Krien, Y.; Elmostafa, Z.; Leone, F., and Benmohammadi, A., 2024. Shoreline change and climatic variability along the Moulay Bousselham coast (Moroccan Atlantic). Journal of Coastal Research, 40(5), 860–874. Charlotte (North Carolina), ISSN 0749-0208. Sandy coasts in Morocco are increasingly threatened by erosion. It is thus crucial to investigate the extent and causes of shoreline change to propose mitigation strategies to stakeholders. This study investigates the long-term shoreline dynamics of Moulay Bousselham (1949–2016) and its relationship with climate variability indices, namely the North Atlantic Oscillation, East Atlantic Oscillation, and West Europe Pressure Anomaly (WEPA). The analysis, which employs geospatial techniques and the Digital Shoreline Analysis System, reveals significant temporal and spatial variability in shoreline changes characterized by phases of erosion and accretion. The study identifies distinct periods of retreat and growth, highlighting the complex nature of coastal dynamics. The correlation analysis between wave parameters and climatic indices emphasizes the influential role of the WEPA index in controlling winter oceanic phenomena. The winter of 2013/14, marked by the highest WEPA, corresponds to the most energetic conditions in at least 70 years, underscoring the index's significance in understanding local climate variability. While acknowledging methodological challenges and uncertainties inherent in shoreline displacement calculations, the study establishes a noteworthy correlation between the WEPA index and shoreline dynamics. This research contributes valuable insights into the intricate interactions between climate variability and coastal evolution, emphasizing the need for refined methodologies and a comprehensive understanding of factors influencing shoreline changes. [ABSTRACT FROM AUTHOR]

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

The bridle shiner (Notropis bifrenatus) is a small cyprinid native to the eastern United States and Canada. Bridle shiner populations have declined across their range, and the species now receives concern status or legal protection in 13 states and two provinces. Bridle shiners were historically found in southern and western Maine in densely vegetated, shallow habitats along the shorelines of streams and ponds. We surveyed areas of Maine that supported historical bridle shiner populations using environmental DNA (eDNA) and traditional seine netting methods, and then used eDNA sampling to survey areas with unknown bridle shiner presence. We rediscovered bridle shiner populations at 11 of 32 historically occupied waterbodies and documented bridle shiners in four additional waterbodies. We determined that both eDNA and seine net surveys are viable options for monitoring bridle shiners in Maine and identified ways to streamline the eDNA methods used in this study to reduce the time and cost of future surveys. [ABSTRACT FROM AUTHOR]

Living shorelines (LS) stabilize eroding banks while providing more natural habitats and creating a gentler slope for enhanced migration of flora and fauna migration as sea levels rise. Typical LS practices include using several different materials, including oyster shell bags, to stabilize shorelines and planting marsh grasses. However, incorporating other important species interactions among marsh organisms can improve LS function and stability. For example, ribbed mussels, Guekensia demissa, benefit marsh plants by adding nutrients and stabilizing sediments. Unfortunately, mussels are not typically included in management and restoration practices. In this study, the objective was to investigate whether ribbed mussels facilitate marsh grass growth at a LS site in the southeastern US. We conducted field surveys for mussel abundance and recruitment, and a manipulative in situ experiment at an established LS site in Georgia to explore the impacts of adding mussels. Although mussel treatment did not have a significant effect on Spartina alterniflora metrics (i.e., density, height, biomass), Spartina plots with high mussel density exhibited ~300% increase in biomass relative to the start of the experiment, while plots without mussels only increased by ~100%. Some of the variability within treatments can be explained by high and sustained mussel mortality throughout the experimental period, likely due to predation, that impacted the actual mussel densities in our plots. We found that Spartina height, density, and biomass exhibited significant positive relationships with mussel biomass. Thus, ribbed mussels may be useful in living shorelines restoration projects if they are planted in sufficient densities, in aggregations, and/or with protective devices. [ABSTRACT FROM AUTHOR]

Erosion poses a significant threat to coastal and estuarine environments worldwide and is further exacerbated by anthropogenic activities and increasing coastal hazards. While conventional engineered structures, such as seawalls and revetments, are commonly employed to protect shorelines from wave impact and erosion, they can also cause detrimental environmental effects. By creating/restoring coastal habitats with engineered structures, hybrid living shorelines offer coastal protection and other co-benefits. Using aerial imagery, we studied the rates of shoreline change before and after living shoreline installation, and between living shorelines and adjacent bare shorelines in three estuaries in New South Wales, Australia. Mangroves had established behind most rock fillets and displayed a trend of increasing canopy cover with fillet age. In the first 3 years since installation, the rates of lateral shoreline change reduced from − 0.20, − 0.16, and − 0.10 m/year to − 0.03, − 0.01, and 0.06 m/year in living shorelines in Hunter, Manning, and Richmond Rivers, respectively. However, when compared to control shorelines, the effectiveness in reducing erosion varied among living shorelines with mean effect sizes of 0.04, − 0.28, and 1.74 across the three estuaries. A more positive rate of shoreline change was associated with an increasing percentage of mangrove canopy area and an increasing length of protected shoreline at wide channels. While hybrid mangrove living shorelines are a promising solution for mitigating erosion and creating habitats at an estuary-wide scale, they may also contribute to downdrift erosion, emphasising the importance of considering site-specific hydrogeomorphology and sediment movement when installing living shorelines. [ABSTRACT FROM AUTHOR]

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Shoreline detection and estimation of changes is a well-established concept in the field of coastal zone management. Recent technological advancements in the form of machine learning (ML) have transformed shoreline detection methodologies. However, due to the constantly changing nature of coasts, identification of the boundary between land and ocean has become an intricate process. In this particular investigation, long-term changes in shoreline along the lower segment of the Indian Sundarbans Delta (ISD) are estimated by employing Landsat sensor's optical imageries spanning 28 years from 1995 to 2023. A fully automated approach involving support vector machine (SVM) classification algorithm with a 99.5% accuracy and zero-crossing edge detection algorithm for shoreline extraction from optical imagery has been proposed. The implementation stage of shoreline extraction utilizes Google Earth Engine's cloud platform. In contrast, subsequent analysis to calculate shoreline changes conforms to the Digital Shoreline Analysis System (DSAS v.5), an extension of ArcGIS Desktop's functionality. This research article examines the long-term shoreline changes in the Indian Sundarban Delta. The study uses three statistical measures: end point rate (EPR), linear regression rate (LRR), and net shoreline movement (NSM). EPR analysis shows significant erosion on Kanak Island and Bhangaduni Island up to 88.21 m. LRR statistics reveal negative trends on the eastern side. NSM analysis highlights maximum accretion in the northwestern part of the delta. This study offers valuable insights into dynamic coastal processes in the area. [ABSTRACT FROM AUTHOR]

This study aimed at delineating the shoreline by using the Digital Shoreline Analysis System (DSAS 5.0) tool and detected the changes of land use/land cover (LULC) by Google Earth Engine (GEE) platform. The shoreline is divided into two zones, whereas Zone I covered 87.12km and Zone II possessed 168.05km. According to End Point Rate (EPR), the mean shoreline change rate of Zone I is 3.55m/year and Zone II is −6.84m/year. Likewise, based on Linear Regression Rate (LRR), the mean shoreline change rate of Zone I is 5.46m/year and Zone II is −4.71m/year, respectively. Apart from that, the Net Shoreline Movement (NSM) recorded in Zone I is 109.42m as well as Zone II is −213.25m, which also revealed how much the shoreline has changed during the last 32 years. This study also used the Kalman filter model to forecast the shoreline positions for 20 years. The most destructive signal is that more than 70% of the coastline is vulnerable due to erosion, whereas 6% is highly vulnerable. By contrast, the results of LULC changes demonstrated the increasing trend of water bodies, built up, and agricultural land while vegetation along with bare land is reduced continuously. The overall accuracy is recorded above 88%, and the kappa co-efficient is found above 0.87 for all three years. The outcome of this study will provide fruitful insight into coastal land use management and adaptation measures against the ongoing along with future threats of shoreline changes to coastal ecosystems and livelihoods. [ABSTRACT FROM AUTHOR]

The permeability of aquifers strongly influences groundwater flow characteristics. Worldwide, coastal groundwater is often the primary freshwater source for coastal communities and ecosystems but is also particularly vulnerable to abstraction since saltwater intrusion may threaten its quality. Thus, understanding coastal permeability is crucial to the sustainable use of coastal groundwater. Here, we present the first global dataset of coastal permeability (CoPerm 1.0), which provides data on coasts' landward, shoreline, and seaward permeability. CoPerm accounts for shoreline characteristics such as cliffs and beaches and contains information on four million segments representing more than two million kilometers of global coastline. Rocky Shores are the most abundant shoreline class, followed by mangroves, beaches, and muddy coasts. Permeability differs between the immediate shoreline (median permeability: 10−12.3 m2), the seaward (median: 10−13.3 m2), and the landward (median: 10−13 m2) sides of the coast. CoPerm provides input data for global coastal groundwater assessments and regional studies of submarine groundwater discharge or saltwater intrusion that can radiate into ecological and economic studies. [ABSTRACT FROM AUTHOR]

Beach morphology can be observed over large spatio-temporal scales, and future shoreline positions can be predicted and coastal risk indicators can be derived by measuring satellite-derived instantaneous waterlines. Long-term satellite missions, such as Landsat and Sentinel-2, provide decades of freely available, high-resolution optical measurement datasets, enabling large-scale data collection and relatively high-frequency monitoring of sandy beaches. Satellite-Derived Shoreline (SDS) extraction methods are emerging and are increasingly being applied over large spatio-temporal scales. SDS generally consists of two steps: a mathematical relationship is applied to obtain a ratio index or pixel classification by machine-learning algorithms, and the land/sea boundary is then determined by edge detection. Indexes from lake waterline detection, such as AWEI or NDWI, are often transferred towards the shore without taking into account that these indexes are inherently affected by wave breaking. This can be overcome by using pixel classification to filter the indices, but this comes at a computational cost. In this paper, we carry out a thorough evaluation of the relationship between scene-dependent variables and waterline extraction accuracy, as well as a robust and efficient thresholding method for coastal land–water classification that optimises the index to satellite radiometry. The method developed for sandy beaches combines a new purpose-built multispectral index (SCoWI) with a refinement method of Otsu's threshold to derive sub-pixel waterline positions. Secondly, we present a waterline extraction pipeline, called Shoreliner, which combines the SCoWI index and the extraction steps to produce standardised outputs. Implemented on the CNES High Performance Cluster (HPC), Shoreliner has been quantitatively validated at Duck, NC, USA, using simultaneous Sentinel-2 acquisitions and in situ beach surveys over a 3-year period. Out of six dates that have a satellite acquisition and an in situ survey, five dates have a sub-pixel RMS error of less than 10 m. This sub-pixel performance of the extraction processing demonstrates the ability of the proposed SDS extraction method to extract reliable, instantaneous and stable waterlines. In addition, preliminary work demonstrates the transferability of the method, initially developed for Sentinel-2 Level1C imagery, to Landsat imagery. When evaluated at Duck on the same day, Sentinel-2 and Landsat imagery several minutes apart provide similar results for the detected waterline, within the method's precision. Future work includes global validation using Landsat's 40 years of data in combination with the higher resolution Sentinel-2 data at different locations around the world. [ABSTRACT FROM AUTHOR]

Nearshore incised valleys are important conduits for the transport of sediment, nutrients, pollutants and organic carbon from the continents to the sea. Therefore, it is essential to understand the autogenic evolution of deltas confined within incised valleys and how such evolution is affected by relative sea‐level rise. To date, limited research has focused on how deltas constrained by incised valleys or other forms of antecedent topography respond to rising sea level. An existing theory of autostratigraphy envisages scenarios in which two‐dimensional or unconfined three‐dimensional fan deltas can experience three evolutionary stages under constant rates of relative sea‐level rise and sediment supply: progradation, autoretreat and post‐autobreak transgression. In this work, an integrated study of geometric numerical models and physical experiments is undertaken to investigate autostratigraphic delta evolution for a variety of incised‐valley geometries, under conditions of constant rates of relative sea‐level rise and sediment supply. Results indicate that interplays of antecedent topography (valley geometries) and sediment mass balance expressed in resultant deltaic geometries can result in autogenic changes in shoreline dynamics and river avulsion frequency on deltas. The following primary findings arise. (i) Compared to valleys with rectangular and trapezoidal cross‐sectional profiles, valleys with triangular cross‐sections tend to contain deltas that experience faster rates of progradation, autoretreat and post‐autobreak transgression under rising sea level, and exhibit a more prominent convex‐seaward shoreline trajectory. (ii) The shoreline trajectory is also related to delta topset geometry, becoming more convex‐seaward under decreasing topset slopes. (iii) River avulsion frequency on deltas with rising sea level varies markedly across valleys with different geometries, even under the same rate of relative sea‐level rise; this is attributed to the difference in temporal evolution of shoreline migration for different valley geometries and the resultant difference in the delta topset aggradation. This study highlights complexities in responses of sedimentary systems under the confinement of different topographic configurations that have hitherto largely been overlooked in sequence‐stratigraphic models. The findings provide insight into future shoreline behaviour and river avulsion hazard on confined deltas, and for decoding the stratigraphic record. [ABSTRACT FROM AUTHOR]

An analytical framework is developed to analyze the interaction of oblique waves with multiple flexible porous breakwaters under the consideration of bottom undulation. The mathematical problem is tackled using the small amplitude water-wave theory, with Darcy's law being applied to account for wave interaction with porous media. The bottom topography is considered to have a finite length, flanked by two semi-infinite sections of uniform bottom. The solution to the boundary value problem is approached by employing the eigenfunction expansion method within the uniform bottom regions. For the varying bottom topography, a modified mild-slope equation (MMSE) is utilized. To address the solution at the slope discontinuity at the bottom, a mass-conserving jump condition is applied. By matching solutions at the interfaces, a set of equations is derived. This system of equations encapsulates the behavior of reflection and transmission coefficients, as well as the force exerted on the breakwaters. These parameters are then investigated across various factors such as the length of the varying bottom, depth ratio, angle of the mooring line, angle of incidence, and flexural rigidity. Graphical representations of the reflection and transmission coefficients, along with the breakwater force, provide insights into the system's behavior under different conditions. The water wave energy can be dissipated for the optimum values of flexural rigidity. The transmission coefficient is observed to be least for higher mooring angle. [ABSTRACT FROM AUTHOR]

Climate refugia can serve as a remnant habitat or stepping stones for species dispersal under climate warming. The largest freshwater lake by surface area, Lake Superior, USA and Canada, serves as a model system for understanding cooling-mediated local refugia, as its cool water temperatures and wave action have maintained shoreline habitats suitable for southern disjunct populations of arctic–alpine plants since deglaciation. Here, we seek to explain spatial patterns and environmental drivers of arctic–alpine plant refugia along Lake Superior's shores, and assess future risk to refugia under moderate (+3.5 °C) and warmest (+5.7 °C) climate warming scenarios. First, we examined how the interactive effects of summer surface water temperatures and wind affected onshore temperatures, resulting in areas of cooler refugia. Second, we developed an ecological niche model for the presence of disjunct arctic–alpine refugia (pooling 1253 occurrences from 58 species) along the lake's shoreline. Third, we fit species distribution models for 20 of the most common arctic–alpine disjunct species and predicted presence to identify refugia hotspots. Finally, we used the two climate warming scenarios to predict changes in the presence of refugia and disjunct hotspots. Bedrock type, elevation above water, inland distance, July land surface temperature from MODIS/Terra satellite and near-shore depth of water were the best predictors of disjunct occurrences. Overall, we predicted 2236 km of the shoreline (51%) as disjunct refugia habitat for at least one species under current conditions, but this was reduced to 20% and 7% with moderate (894 km) and warmest (313 km) climate change projections. [ABSTRACT FROM AUTHOR]

Closed basins within the Great Basin of the western United States were home to numerous lakes during the Pleistocene. One of these paleolakes along the western edge of the Great Basin, Lake Wellington, once filled a 10 × 25‐km expanse of Smith Valley to depths approaching 90 m. This and other lakes that existed during the Pleistocene are generally considered to be pluvial, indicating contemporaneity with either or all a period of cooler climate, increased rainfall and snowmelt, and relatively reduced rates of evaporation as compared to today. Here we combine the results of 36Cl terrestrial cosmogenic nuclide surface exposure dating with soils and geomorphic observations to suggest Lake Wellington was not a pluvial lake but instead the result of a large landslide prior to ~43 ± 15 ka along the West Walker River where it exited Smith Valley. The observations collected also reveal an ancestral course of the West Walker River ~85 m above the current river grade. Attributing the elevation difference to incision caused by active 0.05 ± 0.01 mm a−1 uplift of the underlying Singatse and assuming the ancestral course followed the same path as today places the age of the paleoriver course at ~1.7 Ma. [ABSTRACT FROM AUTHOR]

Understanding the dynamics of shoreline change is essential for efficient coastal management. This research provides a thorough analysis of the long-term changes to the shoreline in the Tamil Nadu district of Tirunelveli, India, spanning five decades (1972–2022). Remote sensing techniques and digital shoreline analysis techniques were employed to investigate the temporal variations and underlying mechanisms influencing shoreline dynamics. Remote sensing methods include satellite imagery analysis, digital shoreline analysis techniques involve GIS-based mapping and measurement of coastal features. The statistical methods like EPR, LRR and NSM techniques were used in this study to identify the shoreline changes. It considers the sedimentary structures of tidal flats and grain size investigations in the region to improve our comprehension of the geological characteristics and sediment dynamics driving shoreline alterations. The findings demonstrate how the shoreline location at Koodankulam changed considerably during the course of the research. This study report spans a sizable length of time and provides significant insights on the long-term behaviour of the Tirunelveli district coastline. Sedimentary structures and grain size investigations provide insights into erosion, deposition patterns, and sediment transport, crucial for understanding shoreline dynamics. The three primary very high erosion hotspots in the research area are Kunjanvilai, Koodankulam, and Kuttam. At a rate of − 23.5, − 23.6, and − 23.6 m/year, maximum erosion is shown by EPR, LRR, and WLR. This study outcomes major two regions like Vijayapathi and Anjugramam are facing more accretion zone. A maximum of 13.33, 11.14, and 11.14 m/year is shown by EPR, LRR, and WLR. According to projection research, the spans will measure 60.67 km in 2042 and 59.62 km in 2032, respectively. [ABSTRACT FROM AUTHOR]

The analysis and prediction of the coastal erosion status are of great significance for maintaining the marine ecological environment, planning urban construction, and coping with climate change. Fangchenggang is located in the southwesternmost part of mainland China. It has the largest harbor in the western region, which provides access to the most convenient channel between southwest China and the Association of Southeast Asian Nations. With the rapid development of China's economy, coastal erosion has occurred in Fangchenggang, and ecological and environmental problems have become increasingly prominent. In this study, we mainly focus on the status analysis and prediction of Fangchenggang coastal erosion based on multisource remote sensing data. A systematic analysis and prediction methods for the coastal erosion state are studied. First, shoreline type changes are analyzed. The index of coastline type diversity is used instead of solely using length changes to analyze shoreline diversity, and the length change intensity is applied to quantify the degree of shoreline change over time for different types of shorelines. Next, the composite index of coastline utilization degree is introduced to further explore the impact of human activities on shorelines. Then, to study the effect of coastal erosion on different types of shorelines in Fangchenggang, the end point rate is used to obtain the coastal erosion rate. Finally, the shoreline trend prediction model for Fangchenggang is established through the spatial distribution of the coastal erosion rate, and we verified that the accuracy of the model is 82%. The model can provide technical support for the integrated prevention and control of coastal erosion hazards. [ABSTRACT FROM AUTHOR]

Cities generate large amounts of plastic waste and thus are often major sources of plastic pollution. Microplastics (particles < 5 mm) are a growing ecological concern as they are readily transported through the environment by wind, flowing water, and other transport processes. Here, we report the findings of an intensive field study that tested associations between prevailing winds and the distribution of plastic pollution around urban lakes (n = 20 lakes) in offshore sediments, shoreline sediments, and surface waters. We tested and found support for the hypothesis that prevailing winds influence the distribution of plastics around lakes. Overall, lakes had greater proportions of macroplastics (i.e., large plastic trash) and microplastics in sediments collected along northern lake shorelines. Notably, we found that macroplastic trash and total microplastics were, respectively, 1.7 and 3 times more abundant in sediments sampled along northern shorelines. Contrary to our expectation, we also found that microplastics in offshore sediments were in greater proportions along western lake shorelines, indicating that wind-driven processes might not explain the distribution of plastics in all lake zones. Furthermore, we observed no discernable patterns within lake surface waters and only captured a handful of suspended microplastic fragments and films from the water column. Overall, our findings revealed that the heterogeneous accumulation of plastic pollution at a lake is influenced, in part, by wind-driven processes. Moreover, these patterns extend across a network of lakes that were distributed across an urbanized landscape. [ABSTRACT FROM AUTHOR]

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

AbstractThis study assessed sandbar-topography changes in Nakdong River Estuary. The island shorelines in the study area, including Jinwoo Island, Shinja Island, and Doyo Sandbar, were analyzed using SPOT satellite images from 2006 to 2022. Shoreline analysis via ArcGIS revealed that Jinwoo Island is expanding at 6.46 m/year towards Nulcha Island. Shinja Island’s western side is expanding at 4.76 m/year, while the eastern side is retreating at 24.41 m/year. Doyo Sandbar’s southern shoreline is retreating at 14.69 m/year, with a gradual decrease in speed. Significant topographical changes indicate that the interlinked barrier islands are undergoing deposition and erosion, altering the shoreline. [ABSTRACT FROM AUTHOR]

The blackchin guitarfish Glaucostegus cemiculus has suffered severe declines and regional extirpation throughout its known distributions. While this species and its relative, the common guitarfish Rhinobatos rhinobatos, have been described in the Mediterranean Sea with co-occurring habitat ranges, no research has recorded the existence or extent of these two separate populations along the Israeli coastal waters. Along a particular coast in Israel, Ma’agan Michael, fishermen have reported annual observations of juvenile guitarfish between June to November for the last forty years. Based on these citizen-based observations themain research objective is to establish whether Ma’agan Michael fulfils all three criteria fromthe literature by Dr Michelle Heupel, allowing it to be acknowledged as a nursery ground for G. cemiculus. The methodology built for this objective integrates biological characteristics data with the identification of a recurrent seasonal distribution. Visual surveys exhibited a significantly higher abundance in Ma’agan Michael when compared to an adjacent area (Caesarea), with 2,096 recorded observations overall. Additionally, using a species-specific modified Catch and Release protocol, a total of 492 juveniles were captured with a beach seine net. During these capturing events, individuals were morphometrically measured and sampled for future genetic analyses. Out of these, 327 specimens were also fitted for PIT tags to track recaptures in subsequent captures. The highest abundance of neonates was caught from August to September each year (2017–2019), and all individuals captured during this study were identified in the field as G. cemiculus, ranging from 20–35 cm in length (85% of captures). Many specimens had an umbilical cord scar (n = 88), with a large percentage possessing visual remains of the yolk sac. For the first time, this study provides an inter-year description of the species Glaucostegus cemiculus present along the Israeli shoreline. [ABSTRACT FROM AUTHOR]

Subsurface barriers have been proposed to protect coastal aquifers from sea-level rise induced seawater intrusion, but the potential for groundwater emergence near subsurface barriers remains unknown. Here, we investigated how emergence changes groundwater flow conditions and influences the protective performance of subsurface barriers with sea-level rise. We tested the subterranean consequences of sea-level rise for cutoff walls and subsurface dams with cross-shore groundwater flow and salt transport models, investigating how barrier design, aquifer properties, and hydrological conditions control the potential for emergence, groundwater partitioning at the barrier, and seawater intrusion with sea-level rise. We find that most subsurface infrastructure cannot prevent seawater intrusion and emergence simultaneously. Subsurface dams spanning more than half of the aquifer thickness created emergence hazards and subsequent groundwater partitioning for all scenarios tested. Cutoff walls were less effective at reducing seawater intrusion for all opening sizes but could reduce the emergence potential compared to similarly sized subsurface dams. Our results demonstrate the challenging trade-offs in mitigating the coastal groundwater hazards of seawater intrusion and emergence with sea-level rise, where groundwater flooding inland of protective infrastructure would require combinations of subsurface impoundments and other mitigation techniques, such as pumping or drains. [ABSTRACT FROM AUTHOR]

Knowledge of hazard conditions due to mass movements is one of the non-structural measures for risk management, urban planning, and protection of natural resources. To obtain this type of mapping, a spatial construction was started by correlating the historical movements with the inherent variables of the terrain by means of the bivariate statistical method, which assigns densities or weights of evidence to estimate the degree of susceptibility. This model was combined with the triggering factors (rainfall and earthquake) to determine the spatiotemporal conditions (hazard). From this procedure, it was obtained that the susceptibility model presents 34% (32.33 km2) of the total area in the high and very high categories, especially in the regions of Mount Siradella and Mount Faro. The validation of the present model obtained a value of 0.945 with the ROC curve. For the hazard condition, 34.1% (32.06 km2) of the study area was found to be in the high and very high category, especially in the municipalities of El Grove, Sanxenxo, and A Illa de Arousa, which have the greatest extension. The present evaluation is an advance in the knowledge of the risk and the actions that can be derived, as in turn, this type of study is an easy tool to obtain due to its low cost and information processing. [ABSTRACT FROM AUTHOR]

Urban beaches, oscillating between development and protection, are more frequently and strongly affected by human activities; therefore, comprehensive and detailed studies of the geomorphological evolution of urban beaches affected by coastal engineering are imperative. Based on 769 satellite images from 1986 to 2023, this study employed a transect-focused approach to investigate the historical shoreline change of Haikou Beach, an urban beach with three nearby offshore artificial islands. The satellite-derived mean water line positions have a temporal resolution of 41 days before 2014 and 9 days after 2018, with a random error of 4.9 m, ranking among the state-of-the-art in this field. This study revealed that the constructions of Pearl Island and Millennium Island as well as five beach nourishment projects mainly exerted a positive impact on the evolution of Haikou Beach. The beach in Pearl Island's wave shadow area may form a tombolo in a hundred years. In the context of heightened coastal engineering development, leveraging the existing large and future larger archives of satellite imagery to analyze the complex changes of urban beaches helps mitigate the absence of field data, aiding in the development of targeted beach erosion protection and remediation strategies with scientific, engineering, and societal significance. [ABSTRACT FROM AUTHOR]

Sandy coastlines are very dynamic spaces affected by a variety of natural and human factors. In Central Chile, changes in oceanographic and wave conditions, modes of inter-annual climate variability such as El Niño Southern Oscillation (ENSO), and extreme events such as earthquakes and tsunamis condition the beach morphology. At the same time, direct human actions alter the arrival of sediments to the coast and their alongshore distribution. Despite the relevance of the beaches for this coastal region and the interesting relationship their morphology has with the aforementioned factors, there is a lack of robust morphological datasets to provide a deep characterization and understanding of the dynamism of the Chilean coast. Based on the information provided by satellite-derived shorelines (SDSs) defined by using the SHOREX algorithm, this paper characterizes the morphological changes of Playa Grande in Cartagena Bay (Central Chile) during the period 1985–2019. The shoreline position data are analyzed in the context of changing beach transforming elements, allowing for a better understanding of the changes according to multiple drivers. While some of these factors, such as earthquakes or coastal storms, have a punctual character, changes in wave patterns vary at different time scales, from seasonal to multi-annual, linked to climate phases such as ENSO. Its effects are translated into shoreline erosion and accretion conditioned by the morphology and orientation of the coast while influenced by the availability of sediment in the coastal system. According to that, a conceptual model of the dynamism and redistribution of sediment in the Bay of Cartagena is proposed. The work proves the high utility that the systematic analysis of multi-decadal SDS datasets obtained from the images acquired in the optical by the Landsat and Sentinel-2 offer for beach monitoring and understanding the coastal dynamism. [ABSTRACT FROM AUTHOR]

In this study, the coastal changes in Hersek Lagoon, have occurred in the 5 years (2015 to 2020) were examined. With the Modified Normalised Difference Water Index (MNDWI), the water areas in the lagoon were determined by object-based classification. When the changes are examined on a regional basis, it is seen that there are erosion and accretion areas were observed. Pearson's r value was examined between End Point Rate (EPR) and Linear Regression Rate (LRR) and a high correlation such as r = 0.921 was obtained. The maximum coastal change was observed as 18.74 m/year with EPR and 18.62 m/year with LRR. [ABSTRACT FROM AUTHOR]

Apart from within the Arumbera Sandstone that spans the Ediacaran–Cambrian boundary, the entire Neoproterozoic succession of the Amadeus Basin has been generally believed to be devoid of metazoan fossils, despite features of possible biogenic origin having been described in the earliest geological mapping reports. Herein are described a suite of curious, rounded impressions preserved upon the surface of a sandstone bed from the basal Neoproterozoic unit, the quartzitic Heavitree Formation that dates to ca 850 Ma. Compared with rounded structures of both organic and inorganic origin, these features resemble fossils of stranded medusae, both modern and ancient, and thereby add a potentially pelagic lifeform to previously described burrowing and sessile forms of likely metazoans, which are preserved as fossils/trace fossils within the Tonian period of the Neoproterozoic elsewhere in the basin. An organic origin for these features would support the contention that the Amadeus Basin harbours the earliest evidence that macroscopic life flourished, albeit briefly, some 215 million years prior to the start of the Ediacaran period and 250 million years before metazoans successfully colonised the late Ediacaran seas. Curious rounded impressions upon a scree sample of Heavitree Formation (ca 850 Ma) are best compared with fossils of stranded jellyfish, both modern and ancient. Such impressions add to the phyla seemingly extant within the Amadeus Basin during the Tonian Period (early Neoproterozoic). Such phyla suggest that metazoan life evolved some 250 Ma earlier than generally believed, although became extinct locally some 10 Ma later. Extinction occurred at ca 840 Ma when changing climate caused the enclosed Amadeus Basin to evolve from conducive shallow aquatic conditions to a harsh evaporitic salt pan. Two later forays into metazoan evolution within the basin are evidenced by burrow-like tubular structures at ca 720 Ma and the Arumberia fossils at ca 560 Ma. [ABSTRACT FROM AUTHOR]

Marks, S. and Potter, C., 2024. Mapping recent coastal shoreline changes in southwestern Alaska using Landsat 8 satellite imagery. Journal of Coastal Research, 40(4), 661–671. Charlotte (North Carolina), ISSN 0749-0208. Coastal communities in Alaska are frequently subjected to storm surges that erode shorelines and riverbanks, which increases flood risks around critical village infrastructure. Coastal erosion in western Alaska may be occurring currently at rates as high as 15 m per year, but the region has not been mapped in enough detail to accurately assess recent shoreline and inland riverbank erosion rates. To update the mapping of changes in all of SW Alaska's coastal margins, Landsat 8 satellite imagery was analyzed to detect trends in the normalized difference water index collected from 2013 to 2023. The normalized difference water index values range from -1 to 1, with negative values indicating majority land that includes soil and live vegetation cover and positive values indicating majority water coverage. Results showed marked coastal shoreline erosion at Chagvan Bay, Hagemeister Island, and Nanvak Bay over the past decade. Additional locations of recent bank erosion were detected on the Kuskokwim River, from its upriver mouth past the city of Bethel. Riverbank erosion was also detected in northern Nushagak Bay, and extensive surface-wetting trends around wetlands and riverbanks were detected near the village of Togiak. Moreover, many villages on the west coast of Alaska and in the Kuskokwim River Delta have recently documented climate change case studies highlighting bank erosion, indicating that a variety of related ecological disturbances are ongoing across the region. [ABSTRACT FROM AUTHOR]

Long, J.H.; Hanebuth, T.J.J.; Durica, J.T., and Hawkes, A.D., 2024. Late Holocene stratigraphy and sedimentary facies distribution of an anthropogenically modified delta plain (Santee River Delta, South Carolina, U.S.A.). Journal of Coastal Research, 40(4), 623–646. Charlotte (North Carolina), ISSN 0749-0208. The Santee River of South Carolina has the second largest watershed in the eastern United States and forms the largest river-fed delta along the U.S. east coast. Anthropogenic modifications to the delta plain of the Santee River, and in many coastal environments within the region, have significantly altered the natural configurations of floodplains, channels, and shorelines. This study incorporated historic and modern state-of-the-art data sets and methods to evaluate the sediment distribution within the modern delta plain as well as the record of environmental change throughout the late Holocene as it is preserved within the subsurface stratigraphy. The study incorporated high-resolution seismo-acoustic and bathymetric data, detailed sediment core analysis, accelerator mass spectrometry 14C dating, micropaleontological analysis, and surface sediment samples to define geomorphic zones based on dominant depositional processes related to fluvial discharge, tides, and waves. Tidal- and wave-influenced conditions were established in the delta plain by around 3 kyr BP and continued into historic times, when the construction of rice fields across most of the delta plain fixed channel positions and isolated floodplains from flood-related sedimentation. Sediment distribution in the modern delta plain is significantly influenced by the maintained network of artificial canals and embankments associated with these historic fields. The influence of these modifications can also be seen within the stratigraphy beneath the delta plain, recording local changes in deposition and erosion that resulted from a modification in water circulation and sediment supply. [ABSTRACT FROM AUTHOR]

Real estate owners face the impact of climate change on both expected risk and returns across property types and geography. This article provides a road map to estimating the risk-return characteristics of coastal real estate properties incorporating the effect of rising sea levels. The approach uses two inputs—a model of real estate risk in the absence of any climate impact, and, separately, a model for the probability of flooding due to proximity to the shoreline. The authors employ a risk model provided by Northfield Information Services to satisfy the first condition and data from FEMA and NOAA combined with a simple, effective, and intuitive flood probability model to satisfy the second condition. Specific examples are shown to illustrate the impact on commercial real estate (CRE) asset returns and risk, which is an essential input for the CRE investor portfolio management process. [ABSTRACT FROM AUTHOR]

Coastal areas, vital for local communities, are subject to significant changes requiring rigorous management. This study focused on assessing the evolution of the Atlantic coastline between Larache and Moulay Bousselham over a period of 60 years, with an emphasis on erosion and accretion risks. The main objective was to understand coastal change trends and identify the most vulnerable areas. Using advanced techniques such as multi-temporal photo interpretation, geographic information system (GIS), and the digital shoreline analysis system (DSAS), the aerial and satellite images from 1963, 1991, 2014, and 2023 were analyzed. The results reveal that zones A (Msitro Beach) and B (Lhayayda Beach) are primarily affected by erosion, with minimal accretion, while zones C (Mersat lghnem beach) and D (Moulay Bousselham Beach) exhibit more intense erosion. This study provides an original contribution by combining advanced analytical methods to inform on the sustainable management of coastal resources. [ABSTRACT FROM AUTHOR]

Groundwater is one of the essential resources that support human life. Excessive exploitation activities can cause groundwater problems such as seawater intrusion, especially in coastal areas. Groundwater salination must be a concern and measured to determine the condition and level of distribution. One of the non-invasive, inexpensive, and efficient methods to see seawater intrusion phenomena is the vertical electrical sounding (VES) technique of electrical resistivity method. This research aimed to analyze the distribution of seawater intrusion in Pelauw Village, Maluku, Indonesia, using the VES and Dar-Zarrouk parameters S and T. The S and T are longitudinal conductance and transversal resistance, respectively. This study collected 16 VES stations spread across residential areas near the coast of Pelauw Village. Groundwater affected by seawater intrusion in the study area has S>1.00 mho and T<1,000 Ωm². Three VES stations are suspected to have experienced seawater intrusion, namely V7, V8 and V12. These three stations are located near the shoreline and densely populated areas. Based on the 2D cross-section, the spread of seawater intrusion toward the land is about 200 meters. This seawater intrusion event is thought to have occurred due to groundwater exploitation by communities around the coast and active tectonic activity. The VES method and Dar Zarrouk Analysis proved compelling enough to delineate the spread of seawater intrusion, so based on these results, it can be a reference for mitigating groundwater pollution. [ABSTRACT FROM AUTHOR]

Public satellite platforms offer regular observations for global coastal monitoring and climate change risk management strategies. Unfortunately, shoreline positions derived from satellite imagery, representing changes in intertidal topography, are noisy and subject to tidal bias that requires correction. The seaward‐most vegetation boundary reflects a change indicator which shifts on event–decadal timescales, and informs coastal practitioners of storm damage, sediment availability and coastal landform health. We present and validate a new open‐source tool VedgeSat for identifying vegetation edges (VEs) from high (3 m) and moderate (10–30 m) resolution satellite imagery. The methodology is based on the CoastSat toolkit, with streamlined image processing using cloud‐based data management via Google Earth Engine. Images are classified using a newly trained vegetation‐specific neural network, and VEs are extracted at subpixel level using dynamic Weighted Peaks thresholding. We performed validation against ground surveys and manual digitisation of aerial imagery across eroding and accreting open coasts and estuarine environments at a site in Scotland. Smaller‐than‐pixel vegetation boundary detection was achieved across 83% of Sentinel‐2 imagery (Root Mean Square Error of 9.3 m). An overall RMSE of 19.0 m was achieved across Landsat 5 & 8, Sentinel‐2 and PlanetScope images. Performance varied by coastal geomorphology, with highest accuracies across sandy open coasts owing to high spectral contrast and less false positives from intertidal vegetation. The VedgeSat tool can be readily applied in tandem with waterlines near‐globally, to support adaptation decisions with historic coastal trends across the whole shoreface, even in normally data‐scarce areas. [ABSTRACT FROM AUTHOR]

Understanding fate and transport processes for per‐ and poly‐fluoroalkyl substances (PFAS) is critical for managing impacted sites. “PFAS Salting Out” in groundwater, defined herein, is an understudied process where PFAS in fresh groundwater mixes with saline groundwater near marine shorelines, which increases sorption of PFAS to aquifer solids. While sorption reduces PFAS mass discharge to marine surface water, the fraction that sorbs to beach sediments may be mobilized under future salinity changes. The objective of this study was to conceptually explore the potential for PFAS Salting Out in sandy beach environments and to perform a preliminary broad‐scale characterization of sandy shoreline areas in the continental U.S. While no site‐specific PFAS data were collected, our conceptual approach involved developing a multivariate regression model that assessed how tidal amplitude and freshwater submarine groundwater discharge affect the mixing of fresh and saline groundwater in sandy coastal aquifers. We then applied this model to 143 U.S. shoreline areas with sandy beaches (21% of total beaches in the USA), indirectly mapping potential salinity increases in shallow freshwater PFAS plumes as low (<10 ppt), medium (10–20 ppt), or high (>20 ppt) along groundwater flow paths before reaching the ocean. Higher potential salinity increases were observed in West Coast bays and the North Atlantic coastline, due to the combination of moderate to large tides and large fresh groundwater discharge rates, while lower increases occurred along the Gulf of Mexico and the southern Florida Atlantic coast. The salinity increases were used to estimate potential perfluorooctane sulfonic acid (PFOS) sorption in groundwater due to salting out processes. Low‐category shorelines may see a 1‐ to 2.5‐fold increase in sorption of PFOS, medium‐category a 2.0‐ to 6.4‐fold increase, and high‐category a 3.8‐ to 25‐fold increase in PFOS sorption. The analysis presented provides a first critical step in developing a large‐scale approach to classify the PFAS Salting Out potential along shorelines and the limitations of the approach adopted highlights important areas for further research. [ABSTRACT FROM AUTHOR]

Background: Along the southern shoreline of Lake Malawi, the incidence of schistosomiasis is increasing with snails of the genera Bulinus and Biomphalaria transmitting urogenital and intestinal schistosomiasis, respectively. Since the underlying distribution of snails is partially known, often being focal, developing pragmatic spatial models that interpolate snail information across under-sampled regions is required to understand and assess current and future risk of schistosomiasis. Methods: A secondary geospatial analysis of recently collected malacological and environmental survey data was undertaken. Using a Bayesian Poisson latent Gaussian process model, abundance data were fitted for Bulinus and Biomphalaria. Interpolating the abundance of snails along the shoreline (given their relative distance along the shoreline) was achieved by smoothing, using extracted environmental rainfall, land surface temperature (LST), evapotranspiration, normalised difference vegetation index (NDVI) and soil type covariate data for all predicted locations. Our adopted model used a combination of two-dimensional (2D) and one dimensional (1D) mapping. Results: A significant association between normalised difference vegetation index (NDVI) and abundance of Bulinus spp. was detected (log risk ratio − 0.83, 95% CrI − 1.57, − 0.09). A qualitatively similar association was found between NDVI and Biomphalaria sp. but was not statistically significant (log risk ratio − 1.42, 95% CrI − 3.09, 0.10). Analyses of all other environmental data were considered non-significant. Conclusions: The spatial range in which interpolation of snail distributions is possible appears < 10km owing to fine-scale biotic and abiotic heterogeneities. The forthcoming challenge is to refine geospatial sampling frameworks with future opportunities to map schistosomiasis within actual or predicted snail distributions. In so doing, this would better reveal local environmental transmission possibilities. [ABSTRACT FROM AUTHOR]

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

The shorelines of Titan's hydrocarbon seas trace flooded erosional landforms such as river valleys; however, it is unclear whether coastal erosion has subsequently altered these shorelines. Spacecraft observations and theoretical models suggest that wind may cause waves to form on Titan's seas, potentially driving coastal erosion, but the observational evidence of waves is indirect, and the processes affecting shoreline evolution on Titan remain unknown. No widely accepted framework exists for using shoreline morphology to quantitatively discern coastal erosion mechanisms, even on Earth, where the dominant mechanisms are known. We combine landscape evolution models with measurements of shoreline shape on Earth to characterize how different coastal erosion mechanisms affect shoreline morphology. Applying this framework to Titan, we find that the shorelines of Titan's seas are most consistent with flooded landscapes that subsequently have been eroded by waves, rather than a uniform erosional process or no coastal erosion, particularly if wave growth saturates at fetch lengths of tens of kilometers. [ABSTRACT FROM AUTHOR]

The study covered a small, shallow lake, intensively used for recreation (sailing, tourist services and port infrastructure). This study aimed to determine the spatial differentiation of bottom sediments and the potential for phosphorus release in five zones, differing mainly in the type of recreation, depth, direct catchment management, shoreline management and macrophyte presence. The results were used to propose protective and restoration measures to improve the water quality of the studied lake. The innovation in the study was the detailed analysis of bottom sediments, which can be a significant source of pollution besides the external load from the catchment and tourist pressure, in the planned management of this ecosystem. Examination of the physicochemical properties of the bottom sediments showed a clear variation in both composition and potential for internal phosphorus loading. The sediments from the profundal zone, where the most boating activity was observed, together with the sediments from the shallow zone where the boats dock (mooring zone), had the highest potential to supply phosphorus to the bottom waters. This fact was demonstrated by the highest total phosphorus (TP) concentrations in sediments (up to 1.32 mgPg−1 DW) and the content of the most mobile fractions (up to 33%). The other zones associated with the marina, fuel zone, tributary and canal were not significant sources of phosphorus to the ecosystem. Based on the above results, a restoration method involving the removal of bottom sediments from the bottom zone was proposed, supported, of course, by protective measures in the catchment (maintaining a buffer zone around the lake and limiting the inflow of pollutants with tributary waters). The proposed measures with sustainable tourist pressure should improve water quality and thus contribute to protecting this valuable natural landscape. [ABSTRACT FROM AUTHOR]

In this work, formal asymptotic solutions of a problem for linear water waves in a bounded basin are constructed. The solutions have the form of asymptotic quasimodes and are used for the description of standing water waves localised near the shoreline. Such short-wavelength quasimodes exist only for a discrete set of frequencies, which are determined by means of a quantisation-type condition. Some numerical results are also addressed. [ABSTRACT FROM AUTHOR]

This document is an editorial for a special issue of the journal "Remote Sensing" that focuses on monitoring terrestrial water resources using satellite sensors. The editorial acknowledges the increasing demand for water resources and the importance of accurately evaluating and tracking them. It discusses the advantages of using satellite technologies for monitoring water resources and highlights studies in the special issue that cover topics such as water body extraction, flood mapping, and coastal wetland dynamics monitoring. The editorial also mentions the use of specific satellite sensors, like satellite altimeters and satellite imagery, for acquiring surface water information. It addresses the challenges of acquiring 3D information about surface water and emphasizes the need to combine satellite observation with model simulation to improve monitoring and understanding of the water cycle. The authors suggest incorporating newly released satellite data, such as SWOT, to enhance the acquisition of information on inland areas, coastal areas, and oceans. [Extracted from the article]

Beach erosion is a process that results in changes to the materials of a shoreline, with erosion being the removal of material from the shoreline more than its addition. Beach erosion on the shorelines causes loss of landforms and a reduction in size, leading to the need for the development of various structures to mitigate beach erosion. Groin is one of the commonly utilized structures for coastal erosion prevention, and groins of various shapes and forms have been developed to minimize beach erosion to the greatest extent possible. We have focused on assessing the impacts of I-head and T-head groin structures on shoreline evolution, approximated through a shoreline evolution model. Various techniques for setting initial conditions and boundary conditions have been discussed. Additionally, we have explored the structural impacts of these two groin types. We considered the average wave crest impact angle obtained from a wave crest impact model on both the left and right sides of the shoreline, differing over a span of four wavelengths. To estimate shoreline evolution for each year, we employed traditional forward time-centered space techniques and the unconditionally stable Saulyev finite differential techniques. The results of shoreline evolution calculations for both groin structures were found to be consistent across the four cases of the wave crest impact model. [ABSTRACT FROM AUTHOR]

Interaction of Anthropic interventions (rigid structures) with coasts is an essential aspect for understanding their geomorphic evolution and incorporating these data into adequate coastal management. This study analyses the short and long-term behavior (1985 to 2019) of shoreline at Santa Marta Bay (Caribbean - Colombia) and their relationship with coastal protection structures. The shoreline variations were analyzed through aerial photographs and satellite images using DSAS tools. The short-term assessment showed initial intense 1985–1991 erosion, with an average retreat speed rate of − 1.6 m·y− 1. It changed gradually since 2003, due to the construction of rigid structures and beach nourishment, decreasing shoreline retreat and even a progradation rate of 0.2 m·y− 1 was observed. The 2009–2019 period, despite recording a positive average value, exhibited a high percentage of erosion profiles. Therefore, in a decadal or long-term analysis (1985–2019), despite engineering works present positive results in the short term, new interventions are required. The coastal erosion is not uniform along the shoreline, because the area is a closed bay with small sediment inputs, the variations in erosion and accretion rates change with human intervention and the installation of new structures. Therefore, quantifying the scale and rate of shoreline changes and correlating them with anthropogenic structures is an essential step in assessing shoreline vulnerability. [ABSTRACT FROM AUTHOR]

This research developed a generic and new theoretical full bottom-up model framework that looks at the single vessel daily voyage through its port call stages, combined with vessel specific technical data per International Maritime Organization (IMO) number which consists of vessel category type, class, and main/auxiliary engine characteristics (i.e. type, speed rate, and tier grade). The developed methodology can be used to investigate daily ports emissions' contribution to the existing emission inventory level in the area. This study claims that in terms of port emission inventory, the port and port-related area should be looked at in a more comprehensive way as the current port time perspective on the examined scenarios and stages has a crucial and significant gap in knowledge, which is significantly important for public and policy decision makers. Therefore, from the social perspective (air quality and health) these additional scenarios and stages should be counted to assess the vessel daily emission performance (vessel's real 'Gross Port Time'). [ABSTRACT FROM AUTHOR]