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Better sanitation and hygiene are very significant for sound health for human lives and it protects various water borne disease. This study aims to find sanitation-hygiene knowledge, practices and impacts on human health of coastal Bangladesh. Rajoir (Sarankhola), Gangarampur (Batiaghata) and Ganapatipur (Kalaroa) villages are purposively designated from shoreline, interim and inland coast. Data are collected with semi-structured questionnaire between July-October 2022 and analyzed through SPSS and map is produced with Arc GIS. Overall about 9.6, 36.3 and 54.1% respondents have good, moderate and poor knowledge regarding sanitation and hygiene. Overall about 57% respondents have accessed sanitary latrines. About 67% respondents claimed that their children deface are thrown in the toilet, followed by, around the house (16%). About 70, 83 and 84% respondents wash their hands with soap/handwash after defecation in shoreline, interim and inland area, followed by, 34, 35 and 27% before taking meal; 19, 19 and 4% before cooking; 9, 21 and 16% after household chores. Cleanliness index are categorized into satisfactory levels except water containers for shoreline (0.677) and inland (0.718) areas. About 96% (shoreline), 91% (interim) and 95% (inland) respondents claim women play a direct role during collection of water. Based on sanitation inspection tool, overall 6, 41, 47 and 3% tube-wells are grouped into very high, high, intermediate and low risk categories. About 57% (shoreline), 48% (interim) and 36% (inland) water sources are grouped into 'high's category. The study suggest to format management committee to monitor proper sanitation and hygiene systems. [ABSTRACT FROM AUTHOR]

In lentic ecosystems (e.g., lakes and ponds), anthropogenic shoreline alterations, such as concrete embankments, severely degrade habitat, affecting fish assemblage structure. Since fishes have a significant influence on lake ecosystems, it is, however, also essential to assess the response of fish behavior to this degradation to better understand the impact of shoreline alteration on lake ecosystems. Here, we investigated freshwater fish migration behavior in 12 small lakes of norther Japan, in which shorelines are environmentally altered, to assess how the habitat alterations can affect fish emigration from the lake to its connecting channels. We collected fishes using traps installed in lake inflow channels and five focal species were selected for the analysis. A generalized linear mixed model showed that emigration of three of five focal fish increased with the increasing proportion of concrete embankment on the lake shorelines. This result suggests that anthropogenic alteration of a lake shoreline structure significantly impacts fish behavior and affects to their emigration from lakes. Further, this finding indicates that behavioral changes caused by anthropogenic alteration are important for understanding the dynamics of small lake ecosystems. [ABSTRACT FROM AUTHOR]

Evidence from bay floor channelling, seismic surveys and core dating has been used to suggest that Port Phillip Bay dried out for a period between about 2800 and 1000 cal. yr BP as sandbars blocked it off from the sea. This model is now supported by the examination of radiocarbon ages from archaeological excavations of Aboriginal shell middens on the shoreline of the Mornington Peninsula on Bunurong Country. This shows a near-continuous use of marine resources by Bunurong people over the last 6000 years for areas south of Rosebud, while those to the north are only of more recent date, following the refilling of the bay in the last millennium. This study provides an example of the integration of traditional, archaeological and geoscience evidence and the way in which local environmental changes impact on society. Radiocarbon dates from Aboriginal places support the argument that a sandbar blocked much of Port Phillip Bay from the sea between about 2800 and 1000 cal. yr BP. Dates from Aboriginal places south of the sand bar show continuity since the bay formed following the post-Pleistocene rise in sea-levels. Dates north of the sandbar indicate that Aboriginal people began exploiting marine resources in this area once the bay refilled about 1000 years ago. [ABSTRACT FROM AUTHOR]

Souza et al. (2022) based on grain size analyses, Optical Stimulated Luminescence (OSL) ages in fluvial sediments, and regional topography affirmed that most of the Paraiba do Sul River Delta (PSRD) has been deposited during the Little Ice Age (LIA). Souza et al. (2022) also inferred that after the LIA, PSRD presents shoreline erosion, using OSL undetermined results, regional topography, and field photographs, suggesting the direct connection of erosion and human intervention along river basin. As the results obtained by Souza et al. (2022) present several inconsistences about coastal evolution, and question previous works about PDRD developed in the last 30 years, we discuss these in three different sections, covering geological, historical, and recent geomorphological changes in PDRD. [ABSTRACT FROM AUTHOR]

Satellite image analysis is a potentially powerful tool for monitoring coastal shoreline positions. This study explores the use of multi-temporal, dual-polarised Sentinel-1 GRD synthetic aperture radar (SAR) imagery with a spatial resolution of 10 m for delineating shorelines. It was conducted in a data-deficient and complex environment (the Niger delta of Nigeria), in a developing country with a cloud-heavy climate. The study focuses on exploring and testing the capability of using multitemporal waterlines from SAR images to derive shoreline positions at high and low tidal states. From 54 Sentinel-1 images recorded in 2017, the study selected 12 images to represent both high and low tidal states. These were spread across the wet and dry seasons in order to account for seasonal differences. Shoreline positions were obtained by identifying the land–water boundary via segmentation using histogram-minimum thresholding, vectorizing and smoothing that boundary, and averaging its position over multiple waterlines. The land–water segmentation had an overall accuracy of 95–99%. It showed differences between wet and dry season shoreline positions in areas dominated by complex creek networks, but similarities along open coasts. The SAR-derived shorelines deviated from the reference lines by a maximum of 43 m (approximately four pixels), and often less than 10 m (one pixel) in most locations (open coast, estuarine, complex creek networks) at high and low tides, except low tide lines in areas with extensive inter-tidal flats at shorelines 70 m to 370 m from the reference lines. However, for applications such as coastal vulnerability assessment, the high tide shoreline is of greater importance. Thus, depending on the application of interest, problems with low tide shoreline delineation may be irrelevant. Despite limitations, notably the relatively small number of images available that were recorded at high or low tide, the method provides a simple, objective, and cost-effective approach to monitoring shorelines at high and low tide. [ABSTRACT FROM AUTHOR]

Interpretation of seismic data over the southeastern flank of the Eratosthenes High shows nine principal seismic stratigraphic units overlying probable faulted basement. Among these are three superposed carbonate platforms that build a stratigraphy exceeding 3000 m. Regional comparisons suggest these range in age from Jurassic to Miocene. The Jurassic carbonate platform exhibits a layered stratigraphy and aggradational deposition style over the whole study area. A Lower Cretaceous platform subsequently developed as a linear, aggrading bank and prograded as multiple high-frequency sequences for more than 40 km into the Eratosthenes High interior, isolating an intrashelf basin that remained connected to the Levant Basin by a narrow seaway. The Jurassic platform margin was a fault-controlled, scalloped escarpment, while the mid-Cretaceous platform was strongly influenced by linear, NW–SE-orientated, fault-controlled sags. The Miocene platform, a shoaling, 'catch-up' neritic shelf, was established after a hiatus during which the flat top of the Cretaceous platform lay below the photic zone. The Miocene platform surface was subsequently incised by Messinian erosional channels that fed offlapping and downstepping regressive carbonate or evaporitic shorelines which tracked Messinian sea-level fall. Updoming and segmentation of the Eratosthenes High occurred during the early Messinian prior to the emplacement of Messinian salt onto its flanks. [ABSTRACT FROM AUTHOR]

The 1257 CE eruption of Samalas volcano, Indonesia, buried the entire island of Lombok beneath various thicknesses of pyroclastic material during this Volcanic Explosivity Index (VEI) 7 event. This study aims to reconstruct the paleo‐topography of western Lombok before the Samalas eruption in 1257 CE and analyse the sedimentation processes that led to its landscape evolution over the last 700 years. Stratigraphic data were collected from various surveys, such as outcrops, coring, drilling, hand auger and wells observation. Electrical resistivity tomography (ERT) measurements were performed to complement the stratigraphic data. A combination of stratigraphy, ERT and topographic data from various sources (topographic map, Digital Elevation Model Nasional [DEMNAS] and Real Time Kinematic [RTK] measurement) is employed to determine the depth of the paleo‐surface. Topographic modelling was performed by subtracting the delta‐DEM (DDEM) from the current‐DEM (CDEM). The result of this operation is a paleo‐DEM, which is used to reconstruct the paleo‐hydrographic features such as shoreline positions and river channels. Modelling results demonstrate that the relief has not been significantly modified, except in lowland areas, which is the sediment accumulation zone. River channels have experienced minor changes, except for the location of the river mouth and the degree of meandering. Significant changes occurred at the shoreline that has prograded by approximately 1.6 km during the last 700 years. A schematic model is built to illustrate the evolution processes of the study area, consisting of the pre‐eruption condition, the immediate post‐eruption condition and development of the current condition. This model further develops the previously proposed model with a higher resolution and simultaneously revises the estimated boundary of the pyroclastic density current (PDC) deposit from previous work. [ABSTRACT FROM AUTHOR]

This paper uses CiteSpace R6.1 bibliometric software to construct a knowledge map of coastal building research, analyses research authors, institutions, countries, keyword co-occurrence and keyword clustering, visualises and analyses the relevant literature collected in WOS, summarises the current state of research, research hotspots and research frontiers in the field, and provides a theoretical basis and decision support for relevant research. Specifically, this paper analyses 2067 records from 1988 to 2023. The results show that the impacts of climate change on coastal buildings are a major focus of research, but there are methodological and data limitations that encourage cross-national and interdisciplinary collaboration to address complex issues. Research trends include adaptive strategies, shoreline response and machine learning, and the need to integrate technical, engineering, social, economic, environmental and ethical dimensions to achieve sustainable and inclusive development. [ABSTRACT FROM AUTHOR]

Environmental damage caused by accidental discharges of pollutants depends in part on the degree of prior contamination, in that increased pollution of an already heavily contaminated region will usually be considered less detrimental than equivalent pollution of a pristine region. Quantitative comparisons of specific pollution events with the extent and severity of prior contamination are rare, owing to difficulties in identifying and assessing contaminants remaining from prior pollution events, and in some cases contaminants from natural sources. The 1989 Exxon Valdez oil spill (EVOS) presents an unusual opportunity to quantitatively evaluate residual contaminants from petroleum sources on shorelines of Prince William Sound (PWS), Alaska. Here, we evaluate surface oil contamination from Monterey Formation petroleum-derived residues (released into PWS from ruptured storage tanks during the 1964 earthquake) on 200 shoreline segments selected at random within the EVOS spill path. We compare these results with previously estimated contamination from the EVOS and from other human activities. Our results indicate that residual shoreline contamination from the EVOS is more than ~ 50% greater than the sum total from human activity sites, that residual contamination by Monterey Formation sources is negligible in comparison to that from the EVOS, and that most of the shorelines in PWS were as close to pristine prior to the EVOS as is likely to be found anywhere else worldwide. [ABSTRACT FROM AUTHOR]

Background: Fish geolocation methods are most effective when they are customized to account for species behavior and study area characteristics. Here, we provide an example of customizing a hidden Markov model (HMM) for reconstructing movement pathways of a high-latitude demersal fish species in a remote island chain using Pop-up Satellite Archival Tag (PSAT) data. Adult Pacific cod were tagged with PSATs while occupying winter spawning grounds in the Aleutian Islands in February 2019. We adapted a demersal fish application of the HMM to (1) add light-based longitude to the data likelihood model, (2) account for possible off-bottom behavior of demersal fishes in the maximum daily depth likelihood, and (3) modify the model framework to accommodate convoluted island topography in the study area. A simulation study was conducted to explore the two primary modifications to the model framework, reflecting boundary for the movement kernel and the Viterbi method of pathway reconstruction, under known conditions. Results: Geolocation was performed on satellite-transmitted and detailed archival data sets from 6 adult Pacific cod at liberty for 21–277 days. Migration from winter spawning to summer foraging areas (range 60–395 km) was detected for the 4 tagged fish that were at liberty for more than 90 days. Light-based longitude was the primary geolocation variable for detecting migrations with precision (root mean square error) estimates of 0.56 degrees during winter and 1.3 degrees during the summer. Simulation studies confirmed the effectiveness of model framework modifications and generated guidelines for use in specific applications. Conclusions: This study demonstrates that post-spawning migrations of Pacific cod in the Aleutian Islands can be detected and characterized using PSAT data. Initial insights into migrations, summer foraging areas, and associated development of appropriate analysis tools will support future Pacific cod movement studies in the Aleutian Islands as well as other regions of Alaska. The adaptations to the HMM presented here will benefit current and future research on demersal fish in other regions as well as fish species that occupy areas with convoluted shorelines or island chain topography. [ABSTRACT FROM AUTHOR]

The impact of global warming presents an increased risk to the world's shorelines. The Intergovernmental Panel on Climate Change (IPCC) reported that the twenty-first century experienced a severe global mean sea-level rise due to human-induced climate change. Therefore, coastal planners require reasonably accurate estimates of the rate of sea-level rise and the potential impacts, including extreme sea-level changes, floods, and shoreline erosion. Also, land loss as a result of disturbance of shoreline is of interest as it damages properties and infrastructure. Using a nonlinear autoregressive network with an exogenous input (NARX) model, this study attempted to simulate (1991 to 2012) and predict (2013–2020) sea-level change along Merang kechil to Kuala Marang in Terengganu state shoreline areas. The simulation results show a rising trend with a maximum rate of 28.73 mm/year and an average of about 8.81 mm/year. In comparison, the prediction results show a rising sea level with a maximum rate of 79.26 mm/year and an average of about 25.34 mm/year. The database generated from this study can be used to inform shoreline defense strategies adapting to sea-level rise, flood, and erosion. Scientists can forecast sea-level increases beyond 2020 using simulated sea-level data up to 2020 and apply it for future research. The data also helps decision-makers choose measures for vulnerable shoreline settlements to adapt to sea-level rise. Notably, the data will provide essential information for policy development and implementation to facilitate operational decision-making processes for coastal cities. [ABSTRACT FROM AUTHOR]

A common inference in research studies of observed and projected changes in global ocean wave height and storm surge, is that such changes are potentially important for long-term coastal management. Despite numerous studies of the impacts of anthropogenic climate change on trends in global wind and waves, a clear link to impacts on sandy coastlines, at global scale, is yet to be demonstrated. This study presents a first-pass assessment of the potential link between historical trends in global wave and storm surge values and recession/progradation rates of sandy coastlines since the 1980s. Global datasets of waves, surge and shoreline change rate are used for this purpose. Over the past 30 + years, we show that there have been clear changes in waves and storm surge at global scale. The data, however, does not show an unequivocal linkage between trends in wave and storm surge climate and sandy shoreline recession/progradation. We conclude that these long-term changes in oceanographic parameters may still be too small to have a measurable impact on shoreline recession/progradation and that primary drivers such as ambient imbalances in the coastal sediment budget may be masking any such linkages. [ABSTRACT FROM AUTHOR]

Understanding the landscape evolution and human-environmental interaction within it is one of the key tasks of early Holocene research. As mobile hunter–gatherers leave few traces of structural organization, understanding their habitats is relevant for comprehending these people. Rarely does the spatial distribution of artifacts correspond to the real pattern of past human activity, but rather shows the pattern of identified artifacts. Geophysical investigations try to fill this gap and have been applied increasingly in archaeological prospection delivering landscape reconstruction, which are verified and fine-tuned using corings and excavations. Despite promising 3D models, a tool to predict the location of undiscovered former human presence and the conditions which influenced people to move across the landscape is not well developed. The primary goal of this paper is to present a methodology for connecting spatial patterns of past human activity based on archaeological and geophysical data. We discuss different GPR (ground-penetrating radar) facies classified at the shoreline of the former Lake Duvensee and geomorphological variables, which leads to the possibility of understanding where and why people chose preferred areas to settle on former islands. We also demonstrate that Mesolithic hunter–gatherer groups preferred dry areas with access to open water for short-term campsites and flatter and more protected areas for specialized and repeatedly occupied campsites. The cardinal orientation of a campsite seems to be secondary to the local peat over-growing process and access to water. [ABSTRACT FROM AUTHOR]

Remote sensing plays a central role in the assessment of environmental phenomena and has increasingly become a powerful tool for monitoring shorelines, river morphology, flood-wave delineation and flood assessment. Optical-based monitoring and the characterization of river evolution at long time scales is a key tool in fluvial geomorphology. However, the evolution occurring during extreme events is crucial for the understanding of the river dynamics under severe flow conditions and requires the processing of data from active sensors to overcome cloud obstructions. This work proposes a cloud-based unsupervised algorithm for the intra-event monitoring of river dynamics during extreme flow conditions based on the time series of Sentinel-1 SAR data. The method allows the extraction of multi-temporal series of spatially explicit geometric parameters at high temporal and spatial resolutions, linking them to the hydrometric levels acquired by reference gauge stations. The intra-event reconstruction of inundation dynamics has led to (1) the estimation of the relationship between hydrometric level and wet area extension and (2) the assessment of bank erosion phenomena. In the first case, the behavior exhibits a change when the hydrometric level exceeds 1 m. In the second case, the erosion rate and cumulative lateral erosion were evaluated. The maximum erosion velocity was greater than 1 m/h, while the cumulative lateral erosion reached 130 m. Time series of SAR acquisitions, provided by Sentinel-1 satellites, were analyzed to quantify changes in the wet area of a reach of the Tagliamento river under different flow conditions. The algorithm, developed within the Python-API of GEE, can support many types of analyses of river dynamics, including morphological changes, floods monitoring, and bio-physical habitat dynamics. The results encourage future advancements and applications of the algorithm, specifically exploring SAR data from ICEYE and Capella Space constellations, which offer significantly higher spatial and temporal resolutions compared to Sentinel-1 data. [ABSTRACT FROM AUTHOR]

Lakes and their shoreline vegetation are rich in biodiversity and provide multiple functions and habitats for fauna and flora. Humans are attracted by the scenic beauty of these ecosystems and the possibilities for recreational activities they offer. However, the use of lakes for recreational activities can lead to disturbance of vegetation, threatening the integrity and functionality of shoreline areas. Recent literature reviews revealed that impacts of the seemingly harmless activities bathing and lingering on the shore on lakeshore vegetation are poorly understood. In this study, we analysed the effects of shoreline use connected with bathing on the structure, composition and diversity of lakeshore vegetation. Vegetation relevés were recorded in 10 bathing and 10 adjacent control sites in the nature park 'Dahme‐Heideseen' (Brandenburg, Germany). In addition visitor counts were performed. The species composition and the cover of herbaceous and shrub vegetation differed between bathing and control sites, but all sites had a high percentage of plant species not typical for the community. The vegetation parameters did not correlate with visitor counts. The results indicate that the present visitor intensity in the nature park does not impact the vegetation severely. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the sedimentary facies and understand the morphodynamics of the study area, and their results were correlated with various analytical methods. Different analyses such as depositional environmental, statistical, shoreline change, and grain size illustrated the temporal and spatial distribution of sediments. It has previously been claimed that current research locations are locii to fluvial landforms and are affected by fluvial processes. However, there are currently no rivers in the study region. This study was done to better understand the presence of fluvial landforms and to evaluate the previous findings. The dynamic behavior of the coast was revealed through shoreline analysis, which was done using satellite images from various years. Oceanographic parameters and longshore sediment transport play a vital role in geomorphological changes in coastal zones. According to the grain size analysis results, mean values showed that the deposits predominantlyare medium grained. The outcome discussed the spatiotemporal variations in geomorphology, sedimentation, and the function of coastal and fluvial processes on the beach of an island and a sand spit. Also highlighted was the role that wave action, fluvial currents, and tidal currents had in the long-term evolution of coastal geomorphological features such as spits, beaches, open coasts, and islands. The standard deviation signifies that the sediments are very well sorted to poorly sorted. Skewness ranges from fine skewed to strongly fine skewed and the kurtosis values show that the sediments are predominately very platykurtic which implies a low-energy environment of deposition. Four sedimentary facies (Facies A, B, C, D) have been found and facies A, B, and C may be wave-influenced deposits, but facies D may be formed by fluvial processes and contain medium to sand-sized particles. The direction of the tip area is also pointing to the south and this result concluded that the tip area is continuously growing. Thus, the results of this study revealed that sediment transport and coastal geomorphology evolution may be governed by two main processes such as the present ocean hydrodynamics and paleo fluvial processes of the study regions. [ABSTRACT FROM AUTHOR]

The contents of chemical elements in the alluvial soils (Fluvisols) in the middle reaches of the Bolshaya Kokshaga River have been studied, The parent material of these soils inherits its composition from sediments of the Central Russian and Cisuralian mineralogical and geochemical provinces. Limits of the bulk contents of elements and their background concentrations have been established, which forms the basis for the environmental monitoring in the Bolshaya Kokshaga Nature Reserve. In total, 34 elements have been determined in the alluvial soils and sands of shoreline shoals; the most abundant elements with concentrations above 1 g/kg are Si, Al, Fe, Ca, K, Mg, Na, Ti, Mn, P, and S. Element concentrations in different types of soils differ in a statistically significant manner. The highest similarity in the elemental composition is observed for meadow and mucky gley soils. As compared with the alluvial soils, the sands of shoreline shoals display the maximum content of Si and the minimum contents of other elements. Soddy soils are characterized by the low content of all elements, except for Si. Meadow and mucky gley soils accumulate larger amounts of Al, Fe, K, Na, Mg, Ti, Mn, Ba, Cr, Zn, Ni, V and As, while eutrophic peat soils (highly mineralized peat deposits) accumulate more Ca, S, P, Sr, Cl, and Rb. Concentrations of As, Cu, V, P, Zr, Ni, and Zn in the alluvial soils exceed their natural abundance in the Earth crust (clarke values) by 1.5–2 times (Kc = 1.5–2), while concentrations of Al, K, Mg, Ti, Sr, Rb, Na, Cl, and Ca are below their clarke values (Kc < 1); concentrations of other elements are comparable to clarke values. [ABSTRACT FROM AUTHOR]

The Purgatoire Valley dinosaur tracksite ('Dinosaur Lake') is North America's largest assemblage of Late Jurassic dinosaur tracks. Roughly 1,300 tracks representing ~100 trackways were reported from a 5,600 m2 area in 1986. Extensive new excavations have revealed more than 800 additional tracks in a 2,600 m2 area. Less abraded tracks farther from the river channel, excavated below bed rock not alluvium, provide high-quality-of-preservation morphometric data. Sauropod (Parabrontopodus) trackways up to 88 m long, some with over 100 successive pes prints, comprise nearly 500 manus and pes tracks. Parallel sauropod trackways confirm previous interpretations of gregarious behaviour, now including a mixed herd of subadult and adult individuals. A preferred westward trackway progression trend likely suggests a single or short-lived episode of gregarious movement along a lake shoreline. Nearly 300 newly recorded tridactyl (theropod) tracks range from 25 to 40 cm in length, with several trackways exceeding 25 or more successive steps. Theropod tracks are assigned to ichnogenus Megalosauripus, also known from the Late Jurassic of Utah, Europe, Central Asia and North Africa. Other theropodan ichnogenera (Hispanosauropus and Therangospodus) from this epoch and region have not been identified. Cross-cutting (over-printing) trackway relationships help constrain the sequence of track registration events. [ABSTRACT FROM AUTHOR]

We conducted a multidisciplinary geophysical experiment to study the relationship between wind, waves, bathymetry, and microseisms in Yellowstone Lake—a small, isolated body of water in which wind‐driven gravity waves excite low‐amplitude seismic energy at periods ∼1.0 s with a regular daily pattern. During 25 June–4 August 2018, we deployed 40 short‐period seismometers, four meteorological stations, and two wave gauges in and around Yellowstone Lake. These instruments were complemented by seven permanent seismometers on the lake perimeter, and a contemporaneous deployment of 10 lake bottom seismometers (LBS) on the floor of the north‐central portion of the lake. The daily wind cycle, with southwesterly winds rising from ∼0 m/s in the early morning to maxima of 10–15 m/s in the late afternoon, generated lake waves with significant heights of ∼0.3–0.4 m and dominant periods of 1.5–2.5 s, which in turn generated microseisms with dominant periods of ∼0.8–1.2 s, in excellent agreement with the double‐frequency generation mechanism. Microseism energy was strongest on the lake floor stations, followed by the island stations and those along the northeastern coast of the lake, suggesting that these sites are closest to the source region where interference between incident and shoreline‐reflected waves is responsible for microseism generation. Smaller amplitude single‐frequency microseism energy was observed primarily along the northeastern lake shoreline. Both types of microseism energy are sensitive to shoreline morphology and lake wave dynamics, such that long‐term monitoring of lake microseisms may further our understanding of how these processes change over time. Plain Language Summary: Earth's surface is continuously vibrating because of the interaction of ocean waves with the solid Earth. These tiny vibrations are called microseisms and they can be recorded and studied with seismometers. Microseismic data can be used to image the interior of the Earth, track hurricanes and typhoons in near real time, and monitor changes in storm frequency and strength over time as the Earth's climate evolves. Several recent studies have demonstrated that lake waves can also create microseismic energy; however, lake microseisms are recorded at significantly shorter periods than ocean microseisms and it is unclear how they are generated in a relatively small, shallow water environment. To study this question, we deployed arrays of seismometers on the bottom and along the shoreline of Yellowstone Lake. At the same time, we deployed wave gauges in the lake and weather gauges near several of the land‐based seismometers. Analysis of the data showed that the microseisms are created by interference between lake waves with reflections from the shorelines. We suggest that the shorter period of lake microseisms relative to ocean microseisms is related to the smaller size (fetch) of the lakes and the shorter duration of lake winds. Key Points: We present a geophysical data set combining lake‐bottom and land‐based seismic data with full‐spectrum wave data from the lake surfaceYellowstone Lake microseisms are mainly created by a mechanism related to the interference of direct and shoreline‐reflected wavesThe relatively shallow water of lakes may play a role in the differences observed between lake and ocean microseisms [ABSTRACT FROM AUTHOR]

Climate change effects along with anthropogenic activities present the main factors that threaten the existence of heritage sites across the north Nile Delta of Egypt close to the coastline of the Mediterranean Sea. Observing the changes in the landscape close to the archaeological sites is an important issue for decision‐makers in terms of reducing the negative impact of natural events and human activities. The coastal heritage sites are becoming strongly threatened by the rising sea level phenomena that will happen due to global warming. Focusing on the distribution of the archaeological sites, this study aims to detect the areas at risk of shoreline erosion or accretion in the northern shoreline of the Nile Delta. In this study, the changes in the northern shoreline of the Nile Delta were observed and calculated during the last hundred years based on the integration between the old topographic maps from surveys in 1900, 1925 and 1945, optical satellite images captured by Landsat in 1972, 1986 and 2000; Sentinel2 2021; and the Radar SRTM data. The results of this study showed that the changes were enormous with a great shoreline erosion process over the last 121 years recorded along the shoreline in the periods between 1900–1925, 1925–1945, 1945–1972, 1972–1986, 1986–2000 and 2000–2021. The areas eroded were about 5.3, 4.7, 5.6, 8.9, 2.5 and 5.4 km2, respectively. Such negative movements caused the loss of two heritage sites, and the expected changes will lead to the loss of additional heritage sites in the next 500 years. Furthermore, a model was suggested for protecting the coastal heritage sites threatened by the risk of submergence. This study can help the decision‐makers to detect the coastal archaeological sites at risk and create innovative solutions for protecting these irreplaceable heritage sites. [ABSTRACT FROM AUTHOR]

Chan, M.C., 2023. Sizing a small tidal inlet for restoration. Journal of Coastal Research, 39(4), 610–624. Charlotte (North Carolina), ISSN 0749-0208. Coastal inlets located on active shorelines can be vulnerable to shoaling and closure. It is not uncommon for some of these inlets to fall under the category of small tidal inlets with cross-sectional areas <100 m2 and to be transitional in stability characteristics such that neither the classic large-inlet O'Brien-Jarrett equilibrium formulas nor the small-inlet Byrne stability criteria apply fully. The Flax Pond inlet, a dual-jettied small inlet located on the south shore of Long Island Sound, New York, is an example of this class of inlets. The inlet, which connects Flax Pond, a degraded tidal marsh embayment, to Long Island Sound, was analyzed to support a proposed plan to reconstruct the twin jetties and restore the pond's tidal prism to its conditions in the early 1970s to prevent further loss of wetland and ecosystem diversity. The lack of directly suitable stability criteria presented a challenge because an extrapolative use of unsuitable criteria could entail unacceptable risks. The issue necessitated a comprehensive, process-driven analysis of the littoral and inlet conditions to frame a solution. An approach involving multiple stability criteria was followed to determine the inlet dimensions needed to achieve the restoration objectives. It was demonstrated that, with a process-based understanding and informed assumptions, a transitional small inlet can be sized with reasonable confidence. [ABSTRACT FROM AUTHOR]

Living shorelines (LS) are a nature‐based restoration technique that aims to stabilize shorelines while enhancing multiple ecosystem services. In particular, LS are frequently promoted as beneficial for enhancing essential coastal habitats for fish and mobile crustaceans (nekton). In this study, we aimed to assess the effects of LS on nekton habitat across eight LS restoration sites in coastal Alabama, U.S.A., by applying widely‐used community metrics. Nekton abundance, species richness, evenness, and diversity tended to be higher in LS and adjacent unrestored control sites than along nearby hardened shorelines. Community metrics showed no clear effect of LS compared to their adjacent controls, with substantial among‐site variation masking any restoration effect. While this may suggest an ecological equivalence between restored and control sites, there are other possible interpretations; that a lack of difference reflects sampling the same populations at nearby control and restored sites, that differences do exist but sampling effort was insufficient to detect them, or that community metrics may be too insensitive for comparing the effects of various restoration approaches on nekton habitat quality. Further exploration of individual‐based metrics such as growth and condition of key species is warranted, as these may be more sensitive for assessing restoration outcomes and guiding future project designs. [ABSTRACT FROM AUTHOR]

Moisture transport into the Arctic is an important modulator for clouds, radiative forcing, and sea ice change. Transport events}namely, moist-air intrusions}are often associated with Arctic cyclones, and during the summer season we find that the high-latitude land surface is a significant moisture source for intrusions. Summer Arctic cyclones typically originate from the surrounding continental interior and shorelines where during the early stages of intensification the warm sector experiences strong latent heat fluxes from the land surface. In this study, we use multiyear reanalysis data and back-trajectory calculations to quantify the linkages between key continental moisture source regions and water vapor within cyclone-induced intrusions. We also conduct regional soil moisture sensitivity experiments using the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS) to diagnose the land surface moisture contribution for an August 2016 Arctic cyclone case. Results from reanalysis show that land regions on average account for more than 30% of the total moist-air intrusion flux at 70°N during summer. COAMPS case-study experiments reaffirm this result, showing that land surface moisture flux on average accounts for 30% of the intrusion water vapor content. COAMPS experiments further reveal that land surface moisture impacts cyclone intensification and moist-air intrusion cloud water vapor. When the regional soil moisture is reduced, intrusion cloud cover is also reduced, resulting in an increase in the surface solar radiation > 90 W m-2. These results demonstrate that the high-latitude land surface plays an important role in the Arctic summer hydrological cycle and may be increasingly impactful as traditionally cold or frozen soils warm. [ABSTRACT FROM AUTHOR]

Eastern oysters, Crassostrea virginica, are ecologically and economically important coastal species which provide a commercially valuable food product while also improving water quality through filtration, protecting shorelines, and providing habitat. The protozoan parasites Perkinsus marinus and Haplosporidium nesloni commonly infect oysters along the United States Atlantic and Gulf coasts and have been linked to poor oyster health and mass mortality events. In this study, wild oysters were collected from multiple reefs within four tidal creeks along the coast of Georgia to investigate P. marinus and H. nelsoni prevalence and intensity, their potential impact on oyster health, and identify possible drivers of the parasites. A second study occurred on four sites on Sapelo Island, Georgia, with continuous water quality monitoring data to further elucidate potential drivers. Oyster density and condition index, a proxy for health, were measured, and parasites were quantified using a TaqMan probe based quantitative real-time PCR within gill tissue. Real-time PCR showed that 86% of oysters tested were infected by one or both parasites in the coast-wide survey, and 93% of oysters from Sapelo Island were also infected by one or both parasites. Prevalence and infection intensity for both P. marinus and H. nelsoni varied across sites. Overall impacts on oysters were complex—intensity was not linked to oyster metrics in the coastwide study, but oyster condition was negatively correlated with P. marinus prevalence in the Sapelo Island study. Several relationships between both parasites and water quality parameters were identified, providing valuable information about potential drivers that should be investigated further. [ABSTRACT FROM AUTHOR]

The inner shelf and coastal region of the Yellow Sea along the Korean Peninsula are frequently impacted by typhoons. The Mokpo coastal region in South Korea was significantly affected by Typhoon Soulik in 2018, the deadliest typhoon strike to the southwestern coast since Typhoon Maemi in 2003. Typhoon Soulik overran the region, causing extensive damage to the coast, shoreline, vegetation, and coastal geomorphology. Therefore, it is important to investigate its impact on the coastal ecology, landform, erosion/accretion, suspended-sediment concentration (SSC), and associated coastal changes along the Mokpo region. In this study, the net shoreline movement (NSM), normalized difference vegetation index (NDVI), fractional vegetation coverage (FVC), coastal-landform change model, normalized difference suspended-sediment index (NDSSI), and SSC–reflectance relation have been used to analyze the coastal morphodynamics over the typhoon periods. We used pre- and post-typhoon Sentinel-2 MultiSpectral Instrument (MSI) images for mapping and monitoring the typhoon effect and recovery status of the Mokpo coast through short- and medium-term coastal-change analysis. The findings highlighted the significant impacts of typhoons on coastal dynamics, wetland vegetation, and sediment resuspension along the Mokpo coast. It has been observed that typhoon-induced SSC influences shoreline and coastal morphology. The outcome of this research may provide databases to manage coastal environments and a long-term plan to restore valuable coastal habitats. In addition, the findings may be useful for post-typhoon emergency response, coastal planners, and administrators involved in the long-term development of human life. [ABSTRACT FROM AUTHOR]

Worldwide, coastal aquifers have been heavily exploited by socio economic activities for several decades, and climate change and sea level rise have also been threatening coastal aquifers. The authorities and policymakers have been advised to find the solutions in order to achieve sustainable water resources management. The southern part of Po delta, Italy is a low-lying coastal area also experiencing tectonic activity. Along with low-lying topography, unstable shore line and sea level, the groundwater is heavily exploited by this deltaic multilayered system of aquifers. Hence, a multilayer three-dimensional model of this aquifer system has allowed for the investigation of the response of aquifer to natural and anthropogenic exploitation. The present work regards the conceptualization of the multilayer aquifer system using lithological cross-sections, surface water features, and appropriate boundary conditions and the steady-state flow modelling. The spatially distributed elevations of the groundwater table and piezometric head from the different aquifers have been calibrated. The values of model error statistics at a satisfactory range, such as R-squared, mean error, root-mean-squared error and model efficiency, confirm that the developed model is reliable, and calibration is obtained with good match between observed and simulated data. The developed model can be used as a decision-making tool for the authorities and policymakers in order to plan for sustainable water management. [ABSTRACT FROM AUTHOR]

Rapid water-quality monitoring methods for beach water and sand can be helpful for public health authorities to develop comprehensive beach monitoring programs. In this study, we evaluated the performance of the Enterococcus qPCR (USEPA 1609.1) method for quality monitoring of beach water and sand-porewater at two Niagara region beaches in Ontario, Canada (Lakeside and Sunset Beaches). While the USEPA 1609.1 method has been validated for beach water, its potential for assessing associated beach sands (which may function as a microbial reservoir) has not been fully explored. All beach water samples (n = 168) passed the qPCR quality control (QC). However, only 20 out of 48 (41.7%) sand-porewater samples passed the qPCR QC, potentially due to interference by soluble inhibitors. The proportion of the sand-porewater samples passing QC improved slightly to 63 out of 120 (52.5%) with a prefiltration step to remove sand and other large particles. The faecal indicator density in the sand-porewater, tested in parallel, did not correlate with the beach water faecal indicator density. Comparing beach water data for the same-day Enterococcus qPCR threshold with the previous-day E. coli culturing-based threshold across all beach days tested, Enterococcus qPCR analyses identified 3 (7%) and 7 (16%) false positive/lost beach days for Lakeside and Sunset Beaches, respectively. Additionally, of the total beach days tested, Enterococcus qPCR analyses identified 2 (5%) and 1 (2%) false negative/health-risk days for Lakeside and Sunset Beaches, respectively. Sand-porewater testing analyses identified days when faecal indicators (in the sand) exceeded beach water quality thresholds. Compared with conventional E. coli culturing, use of the same-day qPCR method would result in fewer beach postings and could identify several additional health-risk days (when the beaches may not be posted). Future studies could include additional prefiltration steps or modifications in the Enterococcus qPCR protocol to improve the method's applicability for sand quality monitoring. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to determine shoreline change statistics and net erosion and accretion, along the Kuakata Coast, a magnificent sea beach on Bangladesh's southernmost point. Design/methodology/approach: The research follows a three stages way to achieve the target. First, this study has used the geographic information system (GIS) and remote sensing (RS) to detect the temporal observation of shoreline change from the year 1991 to 2021 through satellite data. Then, the digital shoreline analysis system (DSAS) has also been explored. What is more, a prediction has been done for 2041 on shoreline shifting scenario. The shoreline displacement measurement was primarily separated into three analytical zones. Several statistical parameters, including Net Shoreline Movement (NSM), Shoreline Change Envelope (SCE), End Point Rate (EPR) and Linear Regression Rate (LRR) were calculated in the DSAS to quantify the rates of coastline movement with regard to erosion and deposition. Findings: EPR and LRR techniques revealed that the coastline is undergoing a shift of landward (erosion) by a median rate of 3.15 m/yr and 3.17 m/yr, respectively, from 1991 to 2021, 2.85 km2 of land was lost. Naval and climatic influences are the key reasons for this variation. This study identifies the locations of a significantly eroded zone in Kuakata from 1991 to 2021. It highlights the places that require special consideration while creating a zoning plan or other structural design. Originality/value: This research demonstrates the spatio-temporal pattern of the shoreline location of the Kuakata beach, which would be advantageous for the region's shore management and planning due to the impacts on the fishing industry, recreation and resource extraction. Moreover, the present research will be supportive of shoreline vulnerability. Hence, this study will suggest to the local coastal managers and decision-makers for particularizing the coastal management plans in Kuakata coast zone. [ABSTRACT FROM AUTHOR]

In Southern Italy, studies dealing with the analysis of multidecadal land-use/land-cover (LULC) changes at the basin scale are scarce. This is an important gap, considering the deep interrelationships between LULC, soil erosion, and river and coastal dynamics. This study provides a contribution in filling this gap by analyzing the LULC patterns and changes in an area of southern Italy, i.e., the Fortore River basin, which occurred between 1960 and 2018. To this end, we conducted a GIS-aided comparison and analysis of LULC data from 1960, 1990, and 2018, respectively. The LULC changes were analyzed at both the basin and the physiographic unit scale. The results showed that most of the LULC changes occurred between the 1960s and 1990s, while from the 1990s onward, great stability in LULC was evident in the basin. The obtained data were mostly coherent with national-, regional-, and basin-scale trends, although some scale-dependent discrepancies were noted. The river and shoreline dynamics fully reflected the duration and the amount of phases of the changes in LULC stability at the basin scale. [ABSTRACT FROM AUTHOR]

Shoreline change is a severe threat to life and property in wetland regions. Shoreline change analysis is critical for integrated wetland zone management and is accomplished through the field and aerial surveys. The Afram River is a significant source of water, food, and economic activity for Kwahu and its neighbouring communities and a form of funds for the residents. The shoreline, nevertheless, has been transforming because of erosion and accretion. This study examined a low-cost innovative approach using space-based peripheral visuals and metrics. Transects and data analysis for the riverbank were created using the Digital Shoreline Analysis System (DSAS) in the Spatial database. The study employed Landsat images from three historical years (2001, 2015 and 2022) across 22 years. End Point Rate (EPR) and Net Shoreline Movement (NSM) statistics in DSAS were used to determine the extent of change. Questionnaires and key informant interviews were administered to farmers, boat operators, fishermen, and older residents to learn more about the factors responsible for changes in shoreline position. According to the study, 24% of the shoreline erodes at a section, while 86% is stable. The survey's mean erosion rate is -0.24 m/yr, whereas the average accretion proportion is 27 m/yr. The ramifications of the Afram River channel change have affected the socio-economic livelihoods, including out-migration, farm loss and displacement of settlement. The mitigation measure employed by the residents had been relocation, and sandbags at the river shoreline have been adopted as a coping mechanism. As a result, all organisations and participants responsible for these riverbanks should work together to prevent further damage and erosion of the shoreline line and its marine life and resources. The current study demonstrates that integrating aerial photos and quantitative tools for shoreline investigations could be dependable. [ABSTRACT FROM AUTHOR]

The Kanyakumari district lies on the southern tip of Tamil Nadu, India. Nowadays, the economically wealthy coast of this district is profoundly altered in its natural existence, which can be deliberated by using Remote Sensing techniques. In this present study, shoreline change inquiry has been attempted at Vilavancode and Kalkulam taluks using the multitemporal satellite data of Landsat 7 ETM + and the Sentinel for a decade from 2009 to 2019. The shoreline has been demarcated and the End Point Rate is estimated by using the Digital Shoreline Analysis System. The shoreline changes statistics have been categorized into seven classes based on the rate of changes: high erosion, medium erosion, low erosion, stable, low accretion, medium accretion, and high accretion. This investigation helps to sense regional fluctuations and reveals that the area subjected to landward shoreline shift is higher than the seaward shoreline shift during this period. The villages of Iraviputhanthurai (10.61 m/yr), Inaiyam (4.01 m/yr), Mandacaud (8.17 m/yr), and Kodimunai (4.12 m/yr) are subjected to high erosion, whereas high accretion is perceived at the Irayumanthurai village (4.13 m/yr). The impact of coastal erosion on site-specific shorelines is considered in this research. This finding will be helpful for coastal management to reduce the loss of economy and safeguard the future coastal environment. [ABSTRACT FROM AUTHOR]

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The Tagus Estuary is one of the largest in Europe with 320 km2, and it has been, for centuries, a gateway to Lisbon. This study focuses on the Moita-Montijo Bay and on the recent dynamics of its tidal flats and saltmarshes. Aerial photographs, orthomosaics, and very high-resolution satellite imagery were used to analyze landcover and shoreline changes. Tidal flats have shown expansion from 1977 to 1995, but since then, contraction dominated, with a change of position of the tidal flat edge of −2.8 m/year in the north bank and −4.2 m/year in the south bank of the Montijo channel. Most contraction occurred along the route of the fast transport catamarans that started operating in 1995, while in the sector without catamaran navigation, expansion was observed. Saltmarshes have been suffering contraction since 1958, with increased rates after 1995 (−0.38 to −0.44 m/year), especially along the catamaran route (−0.57 to −1.27 m/year). The analysis of the wake generated by different vessel types shows a wake increase with the catamarans, in agreement with the increase in contraction along the Montijo channel. Inside abandoned salt pans, saltmarshes expanded. Since 1995, major changes are also observed along the tidal flat margin, with the formation of coarse lag deposits of coarse sands and shells. Given the contraction increase associated with catamaran traffic and the resulting degradation of the tidal flat and the saltmarshes, it is important to introduce measures for containing contraction. [ABSTRACT FROM AUTHOR]

Satellite‐derived shoreline observations combined with dynamic shoreline models enable fine‐scale predictions of coastal change across large spatiotemporal scales. Here, we present a satellite‐data‐assimilated, "littoral‐cell"‐based, ensemble Kalman‐filter shoreline model to predict coastal change and uncertainty due to waves, sea‐level rise (SLR), and other natural and anthropogenic processes. We apply the developed ensemble model to the entire California coastline (approximately 1,760 km), much of which is sparsely monitored with traditional survey methods (e.g., Lidar/GPS). Water‐level‐corrected, satellite‐derived shoreline observations (obtained from the CoastSat toolbox) offer a nearly unbiased representation of in situ surveyed shorelines (e.g., mean sea‐level elevation contours) at Ocean Beach, San Francisco. We demonstrate that model calibration with satellite observations during a 20‐year hindcast period (1995–2015) provides nearly equivalent model forecast accuracy during a validation period (2015–2020) compared to model calibration with monthly in situ observations at Ocean Beach. When comparing model‐predicted shoreline positions to satellite‐derived observations, the model achieves an accuracy of <10 m RMSE for nearly half of the entire California coastline for the validation period. The calibrated/validated model is then applied for multi‐decadal simulations of shoreline change due to projected wave and sea‐level conditions, while holding the model parameters fixed. By 2100, the model estimates that 24%–75% of California's beaches may become completely eroded due to SLR scenarios of 1.0–3.0 m, respectively. The satellite‐data‐assimilated modeling system presented here is generally applicable to a variety of coastal settings around the world owing to the global coverage of satellite imagery. Plain Language Summary: We present a computer model to predict shoreline change due to waves, sea‐level rise (SLR), and other local processes. We apply the model to the entire California coastline (approximately 1,760 km), much of which is not well monitored using traditional survey methods. Observations of historical shoreline position obtained from satellite images can be used in lieu of traditional shoreline survey data to estimate erosion/accretion trends as well as to calibrate and validate models. By 2100, the model estimates that 24%–75% of California's beaches may become completely eroded due to SLR scenarios of 1.0–3.0 m, respectively. Key Points: We assimilate a large‐scale, ensemble shoreline‐change model with observations of shoreline position derived from Landsat satellitesSatellite‐derived shoreline observations perform similarly to in situ observations for calibrating and validating shoreline modelsThe model estimates that, without interventions, 24%–75% of California's beaches may be completely eroded by 2100 due to future sea‐level rise [ABSTRACT FROM AUTHOR]

The northern California littoral cell of the Klamath River, which is a mixed rocky and sandy system with significant shoreline curvature, was investigated by examining ∼40 yr of satellite‐derived shoreline positions and historical records. We find that an accretion wave of sediment was initiated near the Klamath River mouth in the late 1980s and translated downcoast over the subsequent decades. The wave passed rapidly (∼2,500 m/yr) through a rocky coastal reach with more oblique wave directions and slowly through a sandy reach (∼200 m/yr) where wave crests approach at more normal angles. Within the sandy reach, the accretion wave extended over 200 m offshore, was ∼10 km long, incorporated 20 ± 6 million m3 of sediment, and averaged 1.3 ± 0.4 million m3/yr of longshore sediment transport over a 20‐yr interval. Diffusion of the accretion wave was observed, but the diffusivity coefficient (εobs ∼0.01 m2/s) was lower than values predicted by theory, which we attribute to net sediment transport convergence in the study area caused by the curvature of the shoreline. Examining historical records, we find that increased sediment discharge in the Klamath River occurred during the 20th century from industrial‐scale logging and climatic extremes. Thus, we hypothesize that increased river sediment discharge introduced new sediment to the littoral cell that initiated the observed accretion wave. These hypotheses can be tested with stratigraphic and mineralogic investigations of the broad study area beach that has formed during the past 150 years. Plain Language Summary: The existence of beaches along the world's coasts is dependent on the availability of sand or other sediment sources that build up these landforms. As sediment sources come and go over time, beaches may accrete or erode in response to these changes. These kinds of shoreline change patterns can be measured using new satellite‐based techniques that are especially valuable for coasts with limited ground‐based surveys. We applied these satellite‐based shoreline techniques to a portion of the northern California coast, which revealed that a massive body of sediment appeared on this coast in the 1980s, and that this sediment moved downcoast over the subsequent decades. The sediment stayed in a relatively continuous body—termed a coastal accretion wave—that extended 100's of meters offshore and several kilometers alongshore. The satellite measurements also allowed us to track the evolution of the shape and speed of this accretion wave and compare these results with physical conditions and sediment movement theory. Comparing with historical measurements, maps, and accounts, we hypothesize that sediment from the Klamath River has been a primary source of sediment to this coast, including the formation of the accretion wave and study area's broad beach. Key Points: An accretion wave of ∼20 million m3 of littoral sediment formed in the late 1980s and translated ∼15‐km downcoast over the next 30+ yearsAlongshore diffusion of the wave was less than predicted by theory, which is attributed to transport convergence from the shoreline curvatureIncreases in river sediment discharge from human impacts and climate extremes may have initiated the accretion wave [ABSTRACT FROM AUTHOR]

SAET (Shoreline Analysis and Extraction Tool) is a novel open-source tool to enable the completely automatic detection of shoreline position changes using the optical imagery acquired by the Sentinel-2 and Landsat 8 and 9 satellites. SAET has been developed within the ECFAS (European Coastal Flood Awareness System) project, which is intended to be the first European service for coastal flood forecasting, management, and recovery analysis. The tool is developed to characterise the shoreline response associated with punctual events such as coastal storms as well as any other phenomenon. For a given beach segment, SAET facilitates the selection of the satellite images closest in time to the analysed events that offer an adequate cloud coverage level for analysing the shoreline change. Subsequently, the tool automatically downloads the images from their official repositories, pre-processes them and extracts the shoreline position with sub-pixel accuracy. In order to do so, an initial approximate definition of the shoreline is carried out at the pixel level using a water index thresholding, followed by an accurate extraction operating on the shortwave infrared bands to produce a sub-pixel line in vector formats (points and lines). The tool offers different settings to be adapted to the different coastal environments and beach typologies. Its main advantages refer to its autonomy, its efficiency in extracting complete satellite scenes, its flexibility in adapting to different environments and conditions, and its high subpixel accuracy. This work presents an accuracy assessment on a long Mediterranean sandy beach of SDSs extracted from L8 and S2 imagery against coincident alongshore reference lines, showing an accuracy of about 3 m RMSE. At the same time, the work shows an example of the usage of SAET for characterising the response to Storm Gloria (January 2020) on the beaches of Valencia (E Spain). SAET provides an efficient and completely automatic workflow that leads to accurate SDSs while only relying on publicly available information. The tool appears to be a useful extraction tool for beach monitoring, both for public administrations and individual users. [ABSTRACT FROM AUTHOR]

Coastal aquaculture is undertaken in shallow and usually sheltered waters along the coast, delineated by aquaculture ponds. Illegal usage of coastal aquaculture can lead to conflicts with local communities and environmental problems. Thus, it is necessary to extract the aquaculture boundary to monitor the expansion of coastal aquaculture to the sea. However, it is challenging for most existing algorithms to extract the aquaculture boundary for synthetic aperture radar (SAR) images under a high incident angle (>30 degree) with horizontal transmitted and received (HH) or vertical transmitted and received (VV) polarization. The difficulties come from the following: (1) seawater can be seen on both sides of such boundaries, (2) the contrast of such boundaries is uneven, and (3) the backscattering coefficients in some parts of such boundaries are low. In this paper, a novel dual-link weight random walk (DLRW)-based method is proposed to extract such boundaries. The proposed DLRW is composed of an automatic seed points generation strategy, and the establishment and solving of a random walk model with the dual-link weight. By a coarse-to-fine procedure, DLRW is used to extract the aquaculture boundaries in the whole imagery. Sentinel-1 and GF-3 images in Dalian and Liaodong Bay, China have been used in experiments. Mean offset (MO), root mean square error (RMSE), Overlapped, accuracy within one pixel (WOP), and accuracy within two pixels (WTP) have been used to evaluate the performance with existing methods. Experimental results have demonstrated the proposed DLRW-based method outperforms existing methods in the extraction on aquaculture boundaries. Under the low tide, the DLRW-based method is better than the other two methods with MO, RMSE, Overlapped, WOP, and WTP by at least 5.75 pixels, 10.43 pixels, 2.88%, 11.09%, and 18.04%, respectively. Under the high tide, the DLRW-based method is superior to the other two methods with MO, RMSE, and WTP by at least 3.8 pixels, 10.5 pixels, and 6.3%. In addition, the proposed DLRW-based method has a good ability to extract the shoreline with bedrock, ports, and silt. Therefore, the proposed DLRW-based method can be of great value to coastal aquaculture monitoring, coastal mapping, and other coastal applications. [ABSTRACT FROM AUTHOR]

Featured Application: The present paper evaluates 10 alternative shoreline pond electrode station designs using frames in a linear arrangement of electrodes for HVDC interconnections, against the typical design, according to CIGRE B4.61/2017 (parallel arrangement of electrode frames, with respect to the longitudinal axis of the breakwater), studying it from the point of view of electric field analysis (with emphasis on the near-field). During the design of a shoreline electrode station for High-Voltage Direct Current (HVDC) interconnections, the location of the electrodes plays a critical part, especially in the development of the near-electric field. The basic structure is their linear placement, in the form of successive frames, parallel to the longitudinal axis of the breakwater, as proposed by CIGRE and implemented in existing projects. However, this arrangement requires a considerable breakwater length, which may not be permissible, as in the case of Stachtoroi, one of the two electrode stations being built for the 1 GW, ±500 kV HVDC interconnection between Crete and mainland Greece. This troubled the preliminary study team of the electrode stations, which investigated other possible configurations. In this paper, configurations of linear placements of electrode frames are studied and compared at the preliminary study level in terms of electric field effects (especially the near-field), using an analytical simplified model and the superposition method, to determine the most appropriate arrangement of electrodes that will cover the respective requirements of CIGRE directives B4.61/2017. These arrangements are practically evaluated for two different electrode station locations at Korakia in Crete and at Stachtoroi in Aegina for the Crete–mainland-Greece interconnection, resulting in interesting alternative solutions. [ABSTRACT FROM AUTHOR]

The process of shoreline change is inherently complex and reliable predictions of shoreline position remain a key challenge in coastal research. Predicting shoreline evolution could potentially benefit from Deep Learning (DL), which is a recently developed and widely successful data-driven methodology. However, so far its implementation for shoreline time series data has been limited. The aim of this contribution is to investigate the potential of DL algorithms to predict interannual shoreline position derived from camera system observations at a New Zealand study site. We investigate the application of Convolutional Neural Networks (CNNs) and hybrid CNN - Long Short-Term Memory networks. We compare our results with two established models, a shoreline equilibrium model, and a model that addresses time scales in shoreline drivers. Using a systematic search and different measures of fitness we found DL models that outperformed the reference models when simulating the variability and distribution of the observations. Overall, these results indicate that DL models have potential to improve accuracy and reliability over current models. [ABSTRACT FROM AUTHOR]

Coastal zones are fragile and complex dynamical systems that are increasingly under threat from the combined effects of anthropogenic pressure and climate change. Using global satellite derived shoreline positions from 1993 to 2019 and a variety of reanalysis products, here we show that shorelines are under the influence of three main drivers: sea-level, ocean waves and river discharge. While sea level directly affects coastal mobility, waves affect both erosion/accretion and total water levels, and rivers affect coastal sediment budgets and salinity-induced water levels. By deriving a conceptual global model that accounts for the influence of dominant modes of climate variability on these drivers, we show that interannual shoreline changes are largely driven by different ENSO regimes and their complex inter-basin teleconnections. Our results provide a new framework for understanding and predicting climate-induced coastal hazards. In this study, the authors use a global dataset of satellite-derived shoreline positions, and demonstrate that their interannual evolution is dominated by El Niño through its worldwide influence of sea level, river discharge and ocean waves [ABSTRACT FROM AUTHOR]

Microplastic pellets (MPPs) are one of the significant sources of plastic pollution on shorelines worldwide. In this study, for the first time, we have examined the occurrence of MPPs and their spatial and seasonal distributions, adsorbed contaminants, polymer composition, and ecological risks at eight renowned beaches of Andhra Pradesh, central east coast of India. A total of 3950 MPPs were collected from eight beaches along the central east coast of India during October 2020, representing pre-northeast monsoon (pNEM), and during January 2021, representing the northeast monsoon (NEM). The abundance of MPPs was higher during the NEM than those found in the pNEM. ATR-FTIR and SEM analyses were conducted to characterize the polymer types and weathering patterns of MPPs. Energy-Dispersive X-ray spectrometer (EDS) results show the MPP adsorbance of heavy metals such as Ni, Cr, Cu, Pb, and Zn. The degree of contamination and polymer hazard risks of MPPs were assessed using the pollution load index (PLI) and polymer hazard index (PHI). The conducive wind and currents during the NEM lead to higher MPP abundance than during the pNEM. However, the spatial variations of MPPs showed significant differences among the beaches. This study revealed that the presence of MPPs on the beaches along the central east coast of India might pose a considerable polymer hazard risk to the ecosystem. The substantial surface weathering features of MPPs would lead to more toxic nanoplastics in the future. [ABSTRACT FROM AUTHOR]

The coast of China is periodically impacted by tropical cyclones and storm surges, and has experienced significant coastal erosion problems. Traditional "hard engineering" coastal protection measures used to protect Chinese sandy coasts from storm erosion are found to be expensive and less environmental and even make sandy beach disappearing. In this study, geotextile system as a more flexible material was developed and qualitatively compared with the traditional coastal protection measures. An in-situ permanent revetment was applied with durable geotextile sandbags on the coast of Chudao in China from October 2018 to October 2020, and it was designed for three different testing segments to optimize the stability and construction cost of geotextile sandbags. The field surveys were carried out to collect the in-situ data on beach profiles, wave dynamics, material durability, and sandbag revetment stability. In analyzing the two-year field data collected, it is found that the testing segment-2 wrapped with sheet of plastic geogrids is the most effective of the three testing segments in terms of their coat, structural stability and material durability, and that both the slope of the seabed and the design thickness of geotextile sandbag are the dominate factors responsible for the failure of sandbag structures. • Quantitative assessment of protection performance of geotextile sandbags at an in-situ coastal station is investigated. • The existing equation of geotextile sandbag structure has been discussed in the field conditions. • The appearance of geotextile sandbag structure may not accelerate the erosion of the dune-toe. [ABSTRACT FROM AUTHOR]

New Cuyo Group outcrop data complement recently published seismic and well data that detail the progradational character of the Lower‐Middle Jurassic Neuquén Margin (Argentina). The deepwater margin, with shelf topset (Lajas Formation), slope break and deepwater slope to basin‐floor deposits (Los Molles Formation), prograded northward and westward as large‐scale clinoforms (250–500 m high) for 120 km, during 13 My, supplied by sediment mainly from the North Patagonian Massif. The studied Lajas Formation topsets are themselves progradational, with a 500 m‐thick vertical succession of subaqueous delta, shoreface with associated tidal flat, mouth bar, fluvio‐tidal channel and alluvial plain deposits. This pattern is confirmed by facies analysis in five areas of outcrops and well data but is interrupted by frequent marine transgressions that add a short‐term cyclicity to the succession. A new paleogeographic map suggests previous disagreements on process stratigraphy are due to shoreline/paralic strike variability and to increased basinal process impact as the topset/shelf widened. A marked feature of each Lajas topset sequence is a differential partitioning of sand and mud, though not with a simple proximal to distal grain‐size reduction. The sand‐prone outer shelf passes landward to a channelized muddy shoreline environment, and then to a mixed sandy and muddy channelized coastal and alluvial plain. This type of partitioning, important for the characterization and prediction of reservoir quality, can also be recognized on seismic and well log data. [ABSTRACT FROM AUTHOR]

Autonomous technologies are increasingly used in various areas of science. The use of unmanned vehicles for hydrographic surveys in shallow coastal areas requires accurate estimation of shoreline position. This is a nontrivial task, which can be performed using a wide range of sensors and methods. The aim of the publication is to review shoreline extraction methods based solely on data from aerial laser scanning (ALS). This narrative review discusses and critically analyses seven publications drawn up in the last ten years. The discussed papers employed nine different shoreline extraction methods based on aerial light detection and ranging (LiDAR) data. It should be noted that unambiguous evaluation of shoreline extraction methods is difficult or impossible. This is because not all of the methods reported achieved accuracy, the methods were assessed on different datasets, the measurements were conducted using different devices, the water areas differed in geometrical and optical properties, the shorelines had different geometries, and the extent of anthropogenic transformation. The methods proposed by the authors were compared with a wide range of reference methods. [ABSTRACT FROM AUTHOR]

Understanding the distribution and characterization of natural and non-natural materials on the surface and near-subsurface is important for the development of infrastructure projects. This may be a challenge in highly urbanized areas, where outcrops are scarce, and anthropogenic activities have altered the morphological expression of the landscape. This study tests the integration of ground-penetrating radar (GPR), borehole drilling, aerial imagery, geological mapping, and aerial laser scanning as complementary mapping tools for determining the stratigraphy of glacial and post-glacial Quaternary sediments, the depth to the bedrock, and the distribution of anthropogenic material in Mosvatnet, a lake in Stavanger, Norway. The integration proved to be efficient and enabled the generation of a 3D holistic model, which provided a broad understanding of the subsurface geology and the induced anthropogenic changes in the area through time. Bedrock, till, fluvioglacial, and lacustrine geological units were modeled. Accumulations of post-glacial organic matter were mapped, and the distribution of non-natural infill material was determined. The interpreted dataset suggests that the eastern shoreline of Mosvatnet has artificially prograded about one hundred meters westward since the 1930s and the elevation of the corresponding area has increased by about ten meters relative to the lake level. [ABSTRACT FROM AUTHOR]

As salt marsh habitats face challenges due to sea level rise, storm events, and coastal development, there is an effort to use nature-based approaches such as living shorelines to enhance salt marshes and provide coastal protection. A living shoreline restoration and seasonal monitoring was conducted between July 2016 and October 2018 at an eroding salt marsh on Martha's Vineyard, Massachusetts, Northeastern USA to assess changes in two essential ecosystem services: shoreline stabilization and nitrogen removal. Neither the living shoreline nor unaltered sites demonstrated significant sediment deposition at the marsh edge or on the marsh platform between 2017 and 2018. While we expected nitrogen removal via denitrification to improve at the living shoreline sites over time as abiotic and biotic conditions became more favorable, we found limited support for this hypothesis. We found higher rates of denitrification enzyme activity (DEA) at the living shoreline sites when compared to unaltered sites, but these rates did not increase over time. This study also provides a qualitative assessment of our living shoreline structural integrity through the years, particularly following storm events that greatly challenged our restoration efforts. We demonstrate that living shorelines fortified solely with natural materials may not be the most effective approach to maintain these ecosystem services for Northeastern USA salt marshes exposed to intense northeasterly storms. We suggest the restoration of salt marshes to improve major functions be a priority among managers and restoration practitioners. Initiatives promoting the use of nature-based restoration techniques where environmental conditions permit should be encouraged. [ABSTRACT FROM AUTHOR]

Decades of research using remotely sensed data have extracted evidence for the presence of an ocean in the northern lowlands of Mars in the Hesperian (∼3.3 Ga), but these claims have remained controversial due to the lack of in situ analysis of the associated geologic unit, the Vastitas Borealis Formation (VBF). The Tianwen-1/Zhurong rover was targeted to land within the VBF near its southern margin and has traversed almost 2 km southward toward the interpreted shoreline. We report here on the first in situ analysis of the VBF that reveals sedimentary structures and features in surface rocks that suggest that the VBF was deposited in a marine environment, providing direct support for the existence of an ancient (Hesperian) ocean on Mars. [ABSTRACT FROM AUTHOR]

Plastic pollution in the environment has become a much-discussed issue worldwide. In recent decades, the contamination of all environments has become increasingly evident, in particular, that of water is highly concerning. Ingestion by different animal species under natural conditions has also been demonstrated. Among these is the Talitrid Amphipod Cryptorchestia garbinii, which lives on the banks of the internal waterways and lakes' shorelines. As detritivores species, it is very exposed to microplastics that can be ingested, probably mistaking them for food. Aiming to highlight the microplastic ingestion and the role of this species as an entry point for the food web, we analyzed 80 specimens from 4 sites along the shores of Garda Lake, one of the first lakes in Italy to be studied for this type of contamination. The microplastics ingested were observed and quantified through the Nile Red staining method. We were able to verify the presence of ingested microplastics in all the samples analyzed and, therefore, in the food web. This species could serve as valuable natural models of plastic exposure. Microplastic sentinel species can be used as a proxy for environmental exposure and ecosystem monitoring tools to quantify and assess the impacts of microplastic contamination. [ABSTRACT FROM AUTHOR]

Extraction of shorelines using satellite imagery is an effective method because customary digitization is a long and hectic process. This study focuses on extracting and detecting shoreline changes from Landsat-8 imageries of the Visakhapatnam–Kakinada coast along the east coast of India using an object-based approach. An object-based approach for the automatic detection of coastline from Landsat imagery using the Feature Extraction Workflow by Maximum Likelihood is implemented by the maximum classification method (MLC). The resulting vector polyline is smoothened for every 100 m using ArcGIS software. Delineation of multi-temporal satellite images was performed by visual interpretation from 2014 to 2019 to detect the shoreline changes. Different available techniques and methods are employed to observe shoreline changes. In addition to this, the shoreline information simulated by satellite remote sensing is in fair agreement with RTK GPS observations. The observed and remote sensing shoreline changes help to identify the areas of accretion and eroding zones over the long term. During this study, erosion and deposition changes were observed along RK beach, Rushikonda beach, Uppada beach, and Kakinada beach. The spatial variation rates were calculated using the statistical methods of the Digital Shoreline Analysis System (DSAS) during specific periods. The maximum observed shoreline accretion and erosion rates at Kakinada are 5.3 and –4.35 m/year indicates slight accretion. The maximum observed accretion and erosion rates at Uppada beach are 3.8 and –6.78 m/year, respectively indicating erosion. Similarly, at RK Beach the maximum observed shoreline accretion and erosion rates are 3.68 and –3.68 m/year, respectively indicating the beach is in a stable state. At Rushikonda beach, the maximum observed shoreline accretion and erosion rates are 2.24 and –3.04 m/year, respectively indicating erosion. [ABSTRACT FROM AUTHOR]

Sets of beach ridge plains and sand spit at Laem Pho, Chaiya coast of Surat Thani, the Thai-Malay peninsula, the Gulf of Thailand show their evolution in response to a long-term sea-level change from the middle Holocene to the present. The most landward set of beach ridges defines the paleo-shoreline located at 4.5 km far inland with an elevation up to 4 m of ancient sea level above the present mean sea level. Interestingly, the orientation of beach ridges reflects that they were mainly formed by longshore current in southeast direction likely similar to beach ridges in the other coastal sectors of the western part of the Gulf. The major composition of beach ridge included quartz, whereas minor composition was feldspar. Roundness and sphericity of beach ridge sediments showed sub-rounded and sub-angular. Physical properties of beach sediment and the preservation of feldspar in beach sediment suggest the main source from granite exposure near this coastal plain. Major sediment pathway was possibly supplied from the Phum Rieng canal. Optically stimulated luminescence dating revealed the formation of beach ridge plain here starting from 7,171±460 years BP. The sand spit has been formed at 440 years BP. These ages responded to the formation of beach ridge after sea level had reached the highstand in the middle Holocene. [ABSTRACT FROM AUTHOR]