Frihy, O. and Stanley, J.-D., 2025. Suitable subsea sand-rich borrow areas to replenish eroded beaches of Egypt's Nile Delta. Journal of Coastal Research, 41(5), 733–748. Charlotte (North Carolina), ISSN 0749-0208.

This study focuses on five potential borrow areas of high-quality sands that are identified and delineated on the inner and middle Nile Delta continental shelf. The areas will undergo subsequent detailed geotechnical exploration for possible sand sources suitable to nourish now-eroding beaches and inner shelf areas off northern Egypt. Six areas herein are identified as Ero 1 to Ero 6 from west to east. Location and mapping of these proposed borrow areas are based on integration of textural analysis of offshore core sections and historic borehole soil logs, mapping the late Pleistocene to Holocene stratigraphic sequences of the Nile Delta continental shelf (to ∼50 m thickness) and defining grain-size distributions and dynamics of seabed surficial sediments. The explored sand sources will be used to nourish Nile Delta beaches experiencing increased rates of down-drift erosion resulting from effects of constructed shore-perpendicular structures (jetties and groins), despite such features initially succeeding in reducing previous long-term chronic shore recessions after damming the Nile River by the Aswan High Dam in 1965. Only two subsurface sedimentary units are identified in examined borings on the shelf as potential resource sands that represent basal transgressive and coastal accretion sand ridges. These were previously documented in late Pleistocene and Holocene sequences recovered on the Nile Delta margin. Compatibility analysis indicate that these resource sands (medium-sized, moderately well sorted sands) are suitable to nourish existing eroding delta's beaches, which comprise fine-sized, moderately well sorted sands. The results of this study facilitate the possibility of taking the next GO decision that confirms the probability of the presence, or not, of beach-quality sand suitable for replenishment of Nile Delta shores and adapting them to future relative sea-level rise, delta margin subsidence, and storm-induced sea flooding.

Mattheus, C.R.; Pearce, K.; Rosario, L., and Spitzer, E., 2025. Water-level changes and beach morphodynamics: Insights from topobathymetric monitoring of a receding shoreline, Illinois Beach, Lake Michigan. Journal of Coastal Research, 41(5), 749–769. Charlotte (North Carolina), ISSN 0749-0208.

Great Lakes beach-shoreline morphodynamic responses to meter-scale lake-level fluctuations remain understudied, yet they are important to understand from a coastal resiliency perspective. This paper addresses beach morphodynamics and sand volumetrics along an unarmored stretch of sandy beach shoreline at Illinois Beach State Park, SW Lake Michigan, on the updrift end of a migrating sand-ridge promontory. Captured in topobathymetric monitoring datasets are morphodynamic patterns associated with a rise in base lake level greater than 1.5 m, from 2013 through 2020, and an approximately 1-m fall in base lake level, from 2020 through 2023. This assessment reports on the preconstruction system morphodynamics over decadal lake-level fluctuation, with ongoing geological monitoring efforts offering an opportunity to evaluate the impacts of offshore emergent breakwater construction (in 2023). A loss of approximately 54,000 m² of ridge-and-swale terrain occurred along the historically net-erosional beach with the 2013–20 lake-level rise, manifested as an average elevation loss of 5 m between 2012 and 2020 shoreline positions. Overwash volumes accounted for less than 2000 m³ (<1.5%) of total sand loss from shoreline recession. Eroded sand was mostly exported from the proximal littoral zone, a dynamic that halted with the onset of lake-level fall (2020–23). Postpeak topobathymetric model comparisons suggest a net-volumetric balance across the area of 2012–20 shoreline retreat. Mapped 1939-present shoreline positions suggest that high-magnitude or high-rate lake-level rise events accelerate rates of terrain loss at this overall recessive site. During the latest rise in lake level, around 20,000 m²/y of terrain were lost, whereas the 1939–2023 average rate was less than 2000 m²/y, an order of magnitude lower. Although shoreline positions have advanced to a lakeward position with the post-2020 lake-level fall, this was mostly due to re-exposure with little substantial influx of sand. These are important considerations for coastal managers.

Pendleton, E.A.; Lentz, E.E.; Henderson, R.E.; Heslin, J.L.; Bartlett, M.K., and Sterne, T.K., 2025. Assessing decadal-scale coastal change likelihood to define the accuracy and application of scientific information. Journal of Coastal Research, 41(5), 770–785. Charlotte (North Carolina), ISSN 0749-0208.

Defining the accuracy and uncertainties of scientific data products is critical to the usability and trustworthiness of scientific information for environmental management and conservation purposes, such as coastal resource prioritization, design, adaptation, and mitigation. The U.S. Geological Survey has a new decadal-scale coastal change assessment product that synthesizes nearly two dozen coastal datasets. A supervised machine-learning framework is used to combine existing datasets that describe the landscape and the hazards that affect it to determine the coastal change likelihood (CCL) in the coming decade at a resolution of 10 m per pixel for the NE United States from Maine to Virginia. Here, results from a series of statistical tests conducted on source data, the supervised classification, and the CCL outcomes as compared with historical land-cover change are presented. The overall accuracy of the aggregated land-cover dataset that serves as the foundation to which other source datasets are appended is 94%. The supervised learning classification that determines the final CCL output has an overall accuracy of 92%. The CCL predictions of high expected coastal change were consistent with 95% of the coastal and low-elevation landscape change in the last 20 years, as recorded by the Coastal Change Analysis Program land-cover change atlas. Results suggest that CCL provides accurate estimates of coastal landscape change in the next decade that are consistent with recent observed change. Additionally, best practices for applying CCL for planning purposes are outlined, and citing limitations, knowledge gaps, and opportunities for improved accuracy and further investigation are considered.

Elahi, S.A.E., 2025. Functional state of climate change policy in coastal regions of Bangladesh: Incorporating the voice of coastal communities. Journal of Coastal Research, 41(5), 786–798. Charlotte (North Carolina), ISSN 0749-0208.

Climate change policy attempts to tackle upcoming disaster risks of a country. Coastal regions of Bangladesh have the potential to become economic hubs because of ample prospects in the blue economy sector. Therefore, the assurance of sustainable livelihoods for the coastal population is an urgent necessity. Although various policy initiatives have been undertaken by the government and nongovernmental agencies, a handful of minor issues are posing challenges to their effective implementation and ultimate success. The researcher reviewed the literature regarding the issue but barely found the voice of coastal communities in research work. Thus, this study's objectives focus on feedback from study respondents on the functional state of the coastal freshwater supply system in selected coastal regions of Bangladesh. The prime objective of the study is to explore whether the government of Bangladesh could support the initiatives with necessary policy measures as part of a sustainable pure-water retention and management system. The study's goals are addressed by analyzing field data collected using the mixed method. The study was conducted from November 2023 to February 2024. The data collection techniques were questionnaire survey and key informant interview (KII). Through a stratified random sampling technique, a rationale sample of 408 respondents was drawn proportionately from the four study locations. In addition, 37 KIIs were conducted for validation of the research. The study results show a possible way out of the prevailing barriers in the execution and implementation of safe water policies and strategies for the sustainable livelihoods of Bangladesh's coastal communities. The planned research findings would contribute to establishing a foundation for the sustained well-being of the communities by addressing appropriate policies and strategies for the implementation of a freshwater supply system in the aforementioned regions.

Spaeth, M.K.; Miller, T.E.; Gornish, E.S., and Barberán, A., 2025. Soil microbial community diversity varies by coastal dune successional stage. Journal of Coastal Research, 41(5), 799–810. Charlotte (North Carolina), ISSN 0749-0208.

Coastal sand dunes play a vital role in protecting inland ecosystems and urban areas against storm surges and sea-level rise, which will become increasingly important under human-induced climate change. While plant community dynamics have been found to benefit coastal dune resilience and resistance to disturbances, there has been relatively little investigation of soil microbial communities. Soil microorganisms play a vital role in coastal ecosystems by contributing to soil development, stabilization, and the mediation of plant productivity and diversity. In nutrient-poor environments like sand dunes, plant-microbe interactions are crucial due to their reliance on resource exchange. This study investigated soil microbial communities and whether they are primarily driven by abiotic or biotic conditions across successional habitats of a coastal dune system at St. George Island, Florida, southeastern United States, to help elucidate dune function and resilience. By assessing bacterial and fungal amplicon sequences across a disturbance gradient, it was found that different successional habitats harbored distinct soil communities, which varied in taxonomic diversity and microbial functional groups. Bacteria showed the greatest diversity in interdunes, whereas fungal diversity was greatest in the foredunes. Additionally, it was found that plant and soil characteristics were differentially associated with the soil microbial community based on habitat age, with pH and soil moisture as important compositional drivers. Overall, these findings highlight how coastal dune dynamics differentially influence above- and belowground biotic communities.

Zuck, N.A.; Brown, D.; Kerr, L.; Janssen, M.S., and Miller, J.K., 2025. Influence of beach nourishment on morphological parameters linked to surf quality at Long Branch, New Jersey, U.S.A. Journal of Coastal Research, 41(5), 811–828. Charlotte (North Carolina), ISSN 0749-0208.

Surf quality can be characterized by numerous factors, with surf-zone width, sandbar presence, breaker type, and peel angle being focal along planar beaches. Beach nourishment is generally accepted to negatively affect surf quality through changes in slope and burying of nearshore sandbars. Advocates of nourishment counter that the effects of nourishment on surfing are transitory and diminish as the fill equilibrates. However, existing literature does not quantify surf quality throughout the equilibration process. Herein, a beach nourishment project in Long Branch, New Jersey, United States, is monitored with high-frequency surveys throughout a complete nourishment cycle to quantify the temporal response of surf quality. Surf quality is qualitative and inherently complex; influenced by wave conditions and beach morphology. To isolate the influence of time-varying morphology, this study makes several simplifications; notably, observed waves are not explicitly considered. Instead, a benchmark wave, representative of typical surf conditions, is used to model how morphological changes alter surfing conditions. Breaker type, surf-zone width, and bar presence are tracked as proxies for surf quality throughout the equilibration process using measured profile data. Results show initial deterioration of surf quality measured by a 36% decrease in the surf-zone width and reduction in sandbar presence from 20% to 0%. No detrimental changes to the breaker type were quantified. Surf-zone width and bar presence returned to prenourishment conditions within 5 and 4 months, respectively. Sandbar presence displayed seasonal trends, with widespread formation observed during the winter and a corresponding reduction during the summer. Findings indicate that the negative effects on surf quality are measurable but temporary. Morphologic features that support quality surfing return to prenourishment conditions within 5 months. This duration is approximately 25% of the nourishment interval, which suggests the negative effects on surfing at Long Branch can be classified as transitory.

Johnson, E.I.; Percy, K.L.; Fox, D.M., and Stouffer, P.C, 2025. Declines of migratory songbirds in a deteriorating swamp forest: A link to baldcypress leafroller outbreaks. Journal of Coastal Research, 41(5), 829–842. Charlotte (North Carolina), ISSN 0749-0208

Forested wetlands exist in a balance of hydrologic conditions that facilitate flooding and periodic drying, making their long-term sustainability vulnerable to hydrologic disruptions. Coastal Louisiana baldcypress-tupelo swamp forests have experienced multiple threats over the last 150 years, first by nearly complete clear-cutting, and then through damming and leveeing of rivers and deltaic distributaries. Maurepas Swamp is the second largest swamp forest in the United States, but historical hydrologic disruptions combined with subsidence have left it persistently flooded, thereby preventing tree regeneration. This study examined changes in bird and caterpillar populations between 2003–05 and 2019–20, predicting that swamp specialist birds and caterpillars would be disproportionately affected by deteriorating conditions compared to forest generalists. Standardized point counts were conducted to estimate bird density between closed-canopy relict and open-canopy degraded swamp forest sections and time periods, and a distance-based hierarchical modeling approach was used to adjust for imperfect detection. The U.S. Forest Service National Insect Disease Survey database was examined to assess lepidopteran outbreak frequency and extent, and a longitudinal mixed effects logistic regression model was used to measure temporal changes. As predicted, three swamp specialist bird species (Prothonotary Warbler [Protonotaria citrea], Northern Parula [Setophaga americana], and Yellow-throated Warbler [Setophaga dominica]) decreased in density by >50% over the study period, concordant with a reduction of baldcypress leafroller caterpillar (Archips goyerana) outbreaks after 2006. Generalist Red-bellied Woodpeckers (Melanerpes carolinus) decreased less dramatically through time, perhaps explained by regional rather than localized mechanisms. In contrast, 12 of 16 generalist bird species densities remained stable or increased over time, as did forest tent caterpillar (Malacosoma disstria) outbreaks. Decreases in baldcypress leafroller outbreak extent and frequency may be driven by decreased nutrient availability corresponding to hydrologic impoundment, suggesting that restoration of hydrologic connectivity to freshwater inputs may be critical for restoring swamp wildlife food webs.

Ford, M.R.; Ryan, E.J.; Mules, T.; Tuck, M.E.; Sengupta, M., and Dickson, M.E., 2025. An assessment of the accuracy of shoreline indicators interpreted from aerial photos and very-high-resolution satellite imagery. Journal of Coastal Research, 41(5), 843–855. Charlotte (North Carolina), ISSN 0749-0208.

Shoreline change analysis, underpinned by the interpretation of features from remote imagery, is widely employed in coastal science, engineering, and management. Understanding and quantifying the different sources of uncertainty in the position of shoreline features is essential to provide confidence in the descriptions and calculations of the modes and rates of coastal change. A series of practical tests was developed to better understand and quantify the sources of uncertainty in the position of shoreline indicators mapped as part of a national-scale assessment of coastal change in Aotearoa/New Zealand. First, the positional accuracy of aerial photographs was calculated using tests that were independent of the georeferencing process. The accuracy of the aerial photos examined ranged between 3.61 and 5.03 m (95% confidence), with results showing that the positional accuracy is a product of photo scale and that large-scale photographs have the greatest accuracy. Second, tests were conducted to optimise the zoom level used when digitising different image types to standardise approaches to mapping within a GIS. Third, the precision and accuracy of shorelines mapped by different operators was assessed and showed that despite statistically significant differences in the position of shorelines across operators, the differences were smaller than the pixel size of the imagery. Finally, results reveal that the ability to map a shoreline indicator precisely and repeatedly was a product of the shoreline feature and the clarity of the boundary between landcovers. Results indicate that the positional uncertainty of shoreline features mapped in Aotearoa/New Zealand varied from 0.44 to 10.08 m.

Meury, S.W.; Bernier, J.-F.; Lajeunesse, P., and Chassiot, L., 2025. From industry to recreation: The role of land use changes in shaping an estuarine urban beach system. Journal of Coastal Research, 41(5), 856–872. Charlotte (North Carolina), ISSN 0749-0208.

Densely urbanized coastlines, such as those of the St. Lawrence Estuary in eastern Canada, form complex coastal systems shaped by the co-evolution of anthropogenic and natural processes over time. However, the long history of urbanization within estuaries often leads to significant land use changes that are frequently overlooked in monitoring studies focused on assessing and predicting the evolution of such sedimentary systems. Therefore, it is critical to gain deeper insights into these key moments in the evolution of socionatural systems to facilitate the development of sustainable management practices and decision-making. Located within the St. Lawrence Fluvial Estuary in the Québec City urban agglomeration, Tibbits Cove is a dynamic urban beach that has experienced substantial erosion and undergone numerous transformations due to land use changes over the past two centuries. The alteration of its coastline led to the development of a sandy beach, an atypical but highly valued regional coastal socionatural system. By combining a geohistorical approach with hydrometeorological data and coastline migration rates, this study document the disturbance complex, including natural and human factors, that has driven the development of Tibbits Cove beach and identify the morphosedimentary response and resilience of this urban beach over time. This geohistorical approach revealed that socioeconomic factors, particularly land use changes, have been a greater driver of coastal landscape transformation than natural forces. As human influence increasingly outpaces natural processes in these systems, and this new paradigm stresses the need to thoroughly understand how human decisions and policies act as geomorphic drivers, either altering or facilitating the creation of hybrid landforms, to develop more effective and sustainable management strategies.

Manikkavasagam, N.; Nagarajan, S., and De Witt, P., 2025. Inferential analysis of shoreline erosion: A case study for Jupiter Inlet Lighthouse Outstanding Natural Area. Journal of Coastal Research, 41(5), 873–883. Charlotte (North Carolina), ISSN 0749-0208.

As a critical boundary between terrestrial and aquatic ecosystems, shorelines are highly dynamic and sensitive to various environmental, atmospheric, and anthropogenic factors. Modeling shoreline erosion is a challenging task, and many factors can influence the results. Monitoring the shoreline change and analyzing the factors influencing shoreline erosion are essential actions to preserve coastal ecosystems and natural habitats. This study examined the impact of various atmospheric and ocean parameters on coastal erosion using shoreline data derived from low-altitude uncrewed aerial system images for the years 2017 to 2023. Atmospheric and ocean parameters included tidal range, wind speed, significant wave height, wave period, rainfall, sea-level pressure, and sea-surface temperature. Two significant statistical methods were used for the inferential analysis of shoreline erosion. Conditional entropy was used to quantify the influence of these factors on the shoreline change rate, and partial correlation was used to identify and quantify the significant factors that impacted the shoreline change rate and its directionality. This study was conducted at the Jupiter Inlet Lighthouse Outstanding Natural Area in Florida. This area has about 1200 m of shoreline and has experienced significant retreat up to 30 m over 70 years. Higher tidal ranges are linked with greater erosion, according to the study, which found a substantial negative correlation (coefficient = –1.20, p = 0.012) between tidal range and shoreline erosion rates. On the other hand, the importance of wave period in encouraging sediment deposition is highlighted by the significant positive correlation it showed with accretion (coefficient = 1.61, p = 0.019).

Laksanalamai, J. and Kobayashi, N., 2025. Equilibrium foreshore slope and cross-shore sediment transport rate. Journal of Coastal Research, 41(5), 884–891. Charlotte (North Carolina), ISSN 0749-0208.

The concept of an equilibrium beach profile is extended to estimate cross-shore sediment transport on a measured beach profile. The extended model predicts offshore and onshore sediment transport on the foreshore slope, which are steeper and milder, respectively, than the corresponding equilibrium foreshore slope. A laboratory experiment was conducted to evaluate the model. Equilibrium, steep, and mild foreshores were created on a beach consisting of fine sand and exposed to the same irregular waves. The steep foreshore eroded rapidly and reached equilibrium. Accretion and equilibration on the mild slope were gradual. The calibrated model predicts the measured sediment transport rates on the initial steep and mild foreshores with clear deviations from the equilibrium foreshore profile. The analytical model may eventually be generalized and become applicable to forecast short-term foreshore profile changes using long-term beach profile evolution data.

Griggs, G. and Davar, L., 2025. A tale of three winters: Repeated extreme event damage along the Central California Coast. Journal of Coastal Research, 41(5), 892–906. Charlotte (North Carolina), ISSN 0749-0208.

California's coastal counties, which account for about 70% of the state's population and its marine economy contributes $51.3 billion annually to California's gross domestic product, have experienced multiple destructive extreme events over the past three winters. Repeated coastal storms significantly damaged public infrastructure, homes, businesses, and resources on which coastal communities depend. It is estimated that the California coastal storms between December 2022 and March 2023 alone caused $4.7 billion in economic losses. The frequency and severity of recent coastal flooding and associated impacts emphasize that projected future extreme events are already happening and adversely affecting coastal cities and counties. This study explores the phenomena and consequences of the extreme storms that hit the Central California Coast in the 2022–23, 2023–24, and 2024–25 winters. The intensification and the frequency of recent coastal storms and the magnitude of social and economic impacts highlight that it is time to rethink the typical historic responses of repairing, rebuilding, and reopening. Time is running out and action is needed to develop new or reassess the existing adaptive management strategies and accelerate their implementation to prevent or at least reduce the potential damage from future natural disasters to coastal assets, coastal infrastructure, and the well-being and livelihood of coastal communities.

Breaker, L.C., 2025. Did positive feedback play a role in the circulation of Elkhorn Slough (Monterey Bay, California) during the last three decades of the 20th century? Journal of Coastal Research, 41(5), 907–916. Charlotte (North Carolina), ISSN 0749-0208.

Elkhorn Slough (ES) has grown rapidly since the entrance to a harbor along Monterey Bay, California, was formed in 1946. To document this growth during the period from about 1970 to at least 2000, sufficient data were available to obtain reliable estimates of the increases in the rates of flow that occurred in ES. During this period, the speeds of the surface currents essentially doubled. Two forces, in particular, contributed: semidiurnal tides and frictional forcing along the lateral and bottom boundaries of the slough; additional factors included local winds, transfer of momentum, and most likely, positive feedback (PF). Momentum transfer can be predicted, but PF has the potential to increase beyond reasonable limits if negative feedback does not intervene. The results show that the rates of erosion along the banks and bottom of ES since the 1930s were accelerating, consistent with the idea that acceleration was a key factor that contributed to the overall increase in the surface circulation of ES. A numerical model is proposed where the residuals between the model and the observed data could be compared. Such a model would generates a set of proxy observations: the currents, for example, that would not contain the influence of PF but only the basic physics and numerical approximations that are required for such a model. By comparing the model-generated observations with real data acquired at the same location, such a comparison could be made. Providing a correct interpretation of these results is the challenge. The PF has the potential to unleash energy at levels that continue to increase in the absence of negative feedback; this could explain why ES continued to grow in the absence of sufficient negative feedback when other estuaries along the west coast that have been exposed to similar tidal and boundary forcing have not.