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Aquest treball ha requerit una revisió exhaustiva de la literatura sobre la geometria en planta d'una platja amb espigó en equilibri estàtic. En conseqüència, es presenta de forma ordenada i coherent tot aquest coneixement. Al mateix temps, ha estat necessari revisar i millorar alguns coeficients publicats en la literatura per a poder estendre l'ús de la formulació parabòlica de Hsu& Evans al màxim de corbes de nivell possible. També s'ha modificat la fórmula de Dean per al perfil transversal d'una platja per a poder fer l'ajust, conegudes la posició del cim de la berma i de la profunditat de tancament. Finalment es presenta tota la formulació per a una integració numèrica dels volums de totes les zones d'una platja amb només una variable, diferent en cada zona., Este trabajo ha requerido una revisión exhaustiva de la literatura acerca de la geometría en planta de una playa con saliente en equilibrio estático. En consecuencia, se presenta de forma ordenada y coherente todo ese conocimiento. Al mismo tiempo, ha sido necesario revisar y mejorar algunos coeficientes publicados en la literatura para poder extender el uso de la formulación parabólica de Hsu & Evans al máximo de curvas de nivel posible. También se ha modificado la fórmula de Dean para el perfil transversal de una playa para poder hacer el ajuste conocidas la posición de la cima de la berma y de la profundidad de cierre. Finalmente se presenta toda la formulación para una integración numérica de los volúmenes de todas las zonas de una playa con solo una variable, diferente en cada zona., This study has required an exhaustive review of the literature on the plan geometry of a headland-bay beach in static equilibrium. Consequently, all this knowledge is presented in an orderly and coherent manner. At the same time, it has been necessary to revise and improve some coefficients published in the literature in order to extend the use of the parabolic formulation of Hsu & Evans to as many contour lines as possible. The Dean formulation for the transverse profile of a beach has also been modified to make the adjustment knowing the position of the top of the berm and the depth of closure. Finally, the whole formulation for a numerical integration of the volumes of all the zones of a beach with only one variable, different for each zone, is presented.

The vulnerable Trabucador barrier beach has recently suffered significant storm-induced geomorphological changes. This study presents the monitoring of its shoreline during storm events for assessing their effects on beach dynamics. After fine-tuning the CoastSat tool (i.e. optimal NDWI threshold) for shoreline extraction from Sentinel-2 imagery (S2), results were validated with GNSS-RTK reference shorelines (RMSE = 6.8 m). Shorelines were extracted from Dec-2019 to Feb-2021, encompassing 11 storms (Hs > 2m; duration = 24h), including Gloria (Jan-2020). Results showed that S2 imagery provides enough temporal and spatial resolution to capture the storm effects on the site. The shoreline timeseries gave relevant information about the geomorphological processes occurring during storm events (barrier breaching, erosion, washover), allowing the assessment of their cumulative effects. These results might be important for coastal management, in a site suffering from chronic flooding., Peer Reviewed, Postprint (author's final draft)

How did the Great Salt Lake come to be and what happened to Lake Bonneville? Explore the history of this iconic landmark and its amazing ecosystem that supports all kinds of life today.

While waves are propagating towards the shore and are interrupted by an obstacle like a groyne, they will turn around the tip into the sheltered region of the groyne. This sheltered region is called the shadow zone and contains a reduced wave climate. The turning of the waves is based on the lateral transfer of wave energy along the wave crest, caused by a gradient in wave height. This process is called diffraction. Breaking wave heights and angles inside the shadow zone will be influenced significantly because of wave diffraction. Since variations in breaking wave height and/or angle are responsible for gradients in the alongshore sediment transport, should the process of wave diffraction be taken into account while simulating the shoreline evolution in the vicinity of a groyne. Different methods were found to incorporate the effects of wave diffraction inside the coastline model ShorelineS. The improved model performance of ShorelineS regarding a real-world case study is addressed by using the shoreline of Constanta, Romania. The consequence of incorporating wave diffraction effects onto the shoreline evolution of Constanta is demonstrated in detail. The accretion close to the Southern groyne and erosion near the Northern groyne is visible in the numerical result of the improved model. Therefore, matching the observed anti-clockwise rotation of the coastal cell. Without accounting for diffraction effects, this matching result was not achievable. The transition zone width is found to be an important factor in determining the coastline shape affected by diffraction. After calibration of this parameter, the numerical result demonstrated to be in almost perfect agreement with the observed coastline shape. The root mean square error and bias reduced with factors of 5.5 and 5 compared to the numerical result excluding diffraction effects., Civil Engineering | Hydraulic Engineering | Coastal Engineering

How did the Great Salt Lake come to be and what happened to Lake Bonneville? Explore the history of this iconic landmark and its amazing ecosystem that supports all kinds of life today.

In this episode, Kailee takes us into the past to learn about Great Salt Lake's predecessor - Lake Bonneville.

While waves are propagating towards the shore and are interrupted by an obstacle like a groyne, they will turn around the tip into the sheltered region of the groyne. This sheltered region is called the shadow zone and contains a reduced wave climate. The turning of the waves is based on the lateral transfer of wave energy along the wave crest, caused by a gradient in wave height. This process is called diffraction. Breaking wave heights and angles inside the shadow zone will be influenced significantly because of wave diffraction. Since variations in breaking wave height and/or angle are responsible for gradients in the alongshore sediment transport, should the process of wave diffraction be taken into account while simulating the shoreline evolution in the vicinity of a groyne. Different methods were found to incorporate the effects of wave diffraction inside the coastline model ShorelineS. The improved model performance of ShorelineS regarding a real-world case study is addressed by using the shoreline of Constanta, Romania. The consequence of incorporating wave diffraction effects onto the shoreline evolution of Constanta is demonstrated in detail. The accretion close to the Southern groyne and erosion near the Northern groyne is visible in the numerical result of the improved model. Therefore, matching the observed anti-clockwise rotation of the coastal cell. Without accounting for diffraction effects, this matching result was not achievable. The transition zone width is found to be an important factor in determining the coastline shape affected by diffraction. After calibration of this parameter, the numerical result demonstrated to be in almost perfect agreement with the observed coastline shape. The root mean square error and bias reduced with factors of 5.5 and 5 compared to the numerical result excluding diffraction effects., Civil Engineering | Hydraulic Engineering | Coastal Engineering

The Houtribdijk is a dike intersecting the IJsselmeer and Markermeer, and is partly reinforced by the construction of sandy shores. The sand eliminates the wave loads before they can reach the levee. Making use of sandy shores as flood protection in a freshwater lake environment is unique. The main goal of this thesis was to find the causes of the formation of beach cusps and their morphodynamic behavior at the Houtribdijk. From a literature study, we had found that high-angle wave instabilities are the likely cause of beach cusp formation. This mechanism causes longshore transport of sediment due to differences between wave run-up when waves arrive at the beach under an acute angle. Low-energy environments like these are influenced by higher-energy (stormy) events, caused by wind forcing that produces short, steep, and erosive waves. Topography and bathymetry measurement data along two kilometer-long transects was available, as well as constant hydrodynamic measurements at two locations. Using this data, we quantified the number of cusps, their alongshore position, wavelength, amplitude, and the asymmetry of their top-view shape. By extrapolating the prevailing theory on high-angle wave instabilities, we arrived at a conceptual model for the large scale (kilometer-long) morphological changes of the beach. This conceptual model then related these changes to the hydrodynamics we thought were responsible. The results of this analysis indicate that the number of cusps increases under the influence of high-angle waves. Also, their peaks will start moving in the same direction as the waves, causing them to ‘lean’. Most of these changes are on a time-scale in the order of days, while some larger features migrate in the order of months. We have found that environments like these are very likely to develop beach cusps., Civil Engineering | Hydraulic Engineering

Prediction of the shoreline response behind offshore breakwaters is essential for coastal protection projects. Due to the complexity of the processes behind the breakwaters (e.g., wave diffraction, currents, longshore transport), detailed modelling needs high computational efforts. Therefore, simplifying the process effect in a simpler coastline model could be efficient. In this study, the coastline evolution model ShorelineS is used. A new routine was implemented in the model to adjust the wave heights and angles behind the offshore breakwaters. Two approaches from the literature and a newly introduced one were tested in this study. The model free grid system was used to simply track the breaker line; such an advantage also helped to form tombolo, which is not common for these types of models. The tests showed promising results for single and multi breakwaters systems; however, the newly introduced approach still needs further testing and refinement for better performance and less computational cost., Coastal Engineering

Prediction of the shoreline response behind offshore breakwaters is essential for coastal protection projects. Due to the complexity of the processes behind the breakwaters (e.g., wave diffraction, currents, longshore transport), detailed modelling needs high computational efforts. Therefore, simplifying the process effect in a simpler coastline model could be efficient. In this study, the coastline evolution model ShorelineS is used. A new routine was implemented in the model to adjust the wave heights and angles behind the offshore breakwaters. Two approaches from the literature and a newly introduced one were tested in this study. The model free grid system was used to simply track the breaker line; such an advantage also helped to form tombolo, which is not common for these types of models. The tests showed promising results for single and multi breakwaters systems; however, the newly introduced approach still needs further testing and refinement for better performance and less computational cost., Coastal Engineering

The Houtribdijk is a dike intersecting the IJsselmeer and Markermeer, and is partly reinforced by the construction of sandy shores. The sand eliminates the wave loads before they can reach the levee. Making use of sandy shores as flood protection in a freshwater lake environment is unique. The main goal of this thesis was to find the causes of the formation of beach cusps and their morphodynamic behavior at the Houtribdijk. From a literature study, we had found that high-angle wave instabilities are the likely cause of beach cusp formation. This mechanism causes longshore transport of sediment due to differences between wave run-up when waves arrive at the beach under an acute angle. Low-energy environments like these are influenced by higher-energy (stormy) events, caused by wind forcing that produces short, steep, and erosive waves. Topography and bathymetry measurement data along two kilometer-long transects was available, as well as constant hydrodynamic measurements at two locations. Using this data, we quantified the number of cusps, their alongshore position, wavelength, amplitude, and the asymmetry of their top-view shape. By extrapolating the prevailing theory on high-angle wave instabilities, we arrived at a conceptual model for the large scale (kilometer-long) morphological changes of the beach. This conceptual model then related these changes to the hydrodynamics we thought were responsible. The results of this analysis indicate that the number of cusps increases under the influence of high-angle waves. Also, their peaks will start moving in the same direction as the waves, causing them to ‘lean’. Most of these changes are on a time-scale in the order of days, while some larger features migrate in the order of months. We have found that environments like these are very likely to develop beach cusps., Civil Engineering | Hydraulic Engineering

In the field of coastal engineering computational models are a commonly used tool to gain insight in dynamics of a coastal system, to gain insight in or hindcast the historical development or can be used as engineering tool to assess the efficiency and consequences of a proposed coastal measure. A new coastline model, called ShorelineS, is under development which promises to be applicable for long term simulations on geometric complex coastlines or unstable beach regimes where, for example, spit formation may arise. This new model aims to overcome the gap between existing relatively simple coastline models and more advanced coastal area models. In this thesis the applicability of this new model on spit formation was assessed. A study case in Lobito (Angola), were a natural spit has formed, was used for this purpose. Three research objectives are of interest in this thesis: 1) getting insight in the relevant processes regarding spit formation (in general and for the Lobito spit) 2) validate the longshore sediment transport module of ShorelineS and 3) asses (and improve) the spit formation in ShorelineS. An inventory of existing spit formations around the world and a detailed modelling study (XBeach) on the transport rates around a spit showed that especially the bimodality of the wave climate is an important process influencing the final shape of the spit. Regarding the calculation of the longshore sediment transport it was found that for the modelling of the wave transformation a distinction should be made between the static fixed offshore depth contours and the dynamically changing nearshore depth contours for changing coastline orientations. This distinction is essential to consistently and correctly determine the breaking wave parameters which directly influences the longshore sediment transport calculations. This distinction was implemented in ShorelineS using the concept of a so called ‘dynamic boundary’. The spit formation in ShorelineS was assessed by means o, Civil Engineering | Hydraulic Engineering | Coastal Engineering

In this study, we estimate the shoreline retreat, the vulnerability and the erosion rates of an open beach-dune system under projected sea level rise (SLR) and the action of wind-waves (separately and in combination). The methodology is based on the combination of two state-of-the-art numerical models (XBeach and Q2D-morfo) applied in a probabilistic framework and it is implemented in an open sandy beach in Menorca Island (Western Mediterranean). We compute the shoreline response to SLR during the 21st century and we assess the changing impacts of storm waves on the aerial beach-dune system. Results demonstrate the relevant role that the beach backshore features, such as the berm, play as coastal defense, reducing the shoreline retreat and dune vulnerability rates in the near-term (a few decades ahead) and highlighting the importance of simulating the beach morphodynamic processes in coastal impacts assessments. Our findings point at SLR as the major driver of the projected impacts over the beach-dune system, leading to an increase of ~25% of the volume eroded due to storm waves by the end of the century with respect to present-day conditions., Postprint (published version)

In the field of coastal engineering computational models are a commonly used tool to gain insight in dynamics of a coastal system, to gain insight in or hindcast the historical development or can be used as engineering tool to assess the efficiency and consequences of a proposed coastal measure. A new coastline model, called ShorelineS, is under development which promises to be applicable for long term simulations on geometric complex coastlines or unstable beach regimes where, for example, spit formation may arise. This new model aims to overcome the gap between existing relatively simple coastline models and more advanced coastal area models. In this thesis the applicability of this new model on spit formation was assessed. A study case in Lobito (Angola), were a natural spit has formed, was used for this purpose. Three research objectives are of interest in this thesis: 1) getting insight in the relevant processes regarding spit formation (in general and for the Lobito spit) 2) validate the longshore sediment transport module of ShorelineS and 3) asses (and improve) the spit formation in ShorelineS. An inventory of existing spit formations around the world and a detailed modelling study (XBeach) on the transport rates around a spit showed that especially the bimodality of the wave climate is an important process influencing the final shape of the spit. Regarding the calculation of the longshore sediment transport it was found that for the modelling of the wave transformation a distinction should be made between the static fixed offshore depth contours and the dynamically changing nearshore depth contours for changing coastline orientations. This distinction is essential to consistently and correctly determine the breaking wave parameters which directly influences the longshore sediment transport calculations. This distinction was implemented in ShorelineS using the concept of a so called ‘dynamic boundary’. The spit formation in ShorelineS was assessed by means o, Civil Engineering | Hydraulic Engineering | Coastal Engineering

Extreme coastal storms, especially when incident in areas with densely urbanized coastlines, are one of the most damaging forms of natural disasters. The main hazards originating from coastal storms are inundation and erosion, and their magnitude and extent needs to be accurately assessed for effective management of coastal risk. The use of state-of-art morphodynamic process-based models is becoming standard, with most being applied to straight coastlines with gentle slopes. In this study, the XBeach model is used to assess the coastal response of a curvilinear sensitive deltaic coast with coarse sediment and steep slopes (intermediate-reflective conditions). The tested hypothesis is that changes in wave direction may cause large variations in the magnitude of storm-induced hazards. The model is tested against field data available for the Sant Esteve Storm (December 2008), obtaining an overall BSS (Brier Skill Score) score on the emerged morphological response of 0.68. Later, the 2008 event is used as baseline scenario to create synthetic events covering the range from NE to S. The obtained results show that storm-induced hazards along a highly curvilinear coast are very sensitive to changes in wave direction. Therefore, even under climate scenarios of relatively steady storminess, a potential shift in wave direction may significantly change hazard conditions and thus, need to be accounted for in robust damage risk assessments., Peer Reviewed, Postprint (published version)

Idier, D.; Falqués, A.; Garcin, M., and Rohmer, J., 2018. How observed kilometric sandy shoreline undulations depend on wave climate. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 191–195. Coconut Creek (Florida), ISSN 0749-0208. Coastlines sometimes exhibit km-scale undulations, also called shoreline sandwaves. This work focuses on self-organized undulations and investigates how frequent they are, on which parameters they depend and whether existing theories of morphodynamic instabilities can explain them. We perform a wavelet analysis on shoreline data from areas appearing free of human or geological constraints and representing totally 1268 km around the world. It is found that 61% of cases exhibit undulations with wavelengths in the range 1–10 km. The wave parameter that correlates the best with their existence is the incidence angle with respect to shore normal and, to a lesser extent, the closure depth. The shoreline undulation probability increases with the angle, from 50% for low angles to almost 100% for large angles, suggesting that the High-Angle Wave Instability mechanism (HAWI) would be their primary cause, but that Low-Angle Wave Instability (LAWI) may also play a role. These results are consistent with recent theoretical investigations., Postprint (published version)

Kilometric-scale shoreline sand waves (KSSW) have been observed in the north-east flank of the Dungeness Cuspate Foreland (southeastern coast of the UK). They consist of two bumps separated by embayments with a 350–450-m spacing. We have analysed 36 shoreline surveys of 2-km length using the Discrete Fourier Transformation (DFT), from 2005 to 2016, and seven topographic surveys encompassing the intertidal zone, from 2010 to 2016. The data set shows two clear formation events. In order to test the role of high-angle waves on the KSSW formation, the 10-year wave series is propagated from the wave buoy located at 43 m depth up to a location in front of the undulations at 4 m depth using the SWAN wave model. The dominating SW waves arrive with a very high incidence angle (~ 80°) while the NE waves arrive almost shore normal. The ratio R, which measures the degree of dominance of high-angle waves with respect to low-angle waves, correlates well with the shoreline DFT magnitude values of the observed wavelength undulations. In particular, the highest R values coincide with the formation events. Finally, a linear stability model based on the one-line approximation is applied to the Dungeness profile and the 10-year propagated wave series. It predicts accurately the formation moments, with positive growth rates in the correct order of magnitude for wavelengths similar to the observed ones. All these results confirm that the shoreline undulations in Dungeness are self-organized and that the underlying formation mechanism is the high-angle wave instability. The two detected formation events provide a unique opportunity to validate the existing morphodynamic models that include such instability., Postprint (author's final draft)

Video showing huge ice stacks on Utah Lake located just south of Vineyard Beach.

Video of ice stacking up at Utah Lake. As the winds blows across the lake, the ice sheets push up on the shoreline, break, and stack up on each other.

Video showing huge ice stacks on Utah Lake located just south of Vineyard Beach.

Video of ice stacking up at Utah Lake. As the winds blows across the lake, the ice sheets push up on the shoreline, break, and stack up on each other.

Time lapse video of ice stacking at Utah Lake. The wind blows the ice along the surface until it hits the shoreline, and then it begins to stack up with stacks reaching amazing heights.

This research has been funded by the Spanish government through the research projects CTM2012-35398 (cofunded by FEDER, U.E.) and CTM2015-66225-C2-1-P (MINECO/FEDER)., This review summarizes the morphological characteristics and dynamics of nearshore sand bars observed in the surf zone of sandy beaches worldwide, with length scales ranging from tens to hundreds of meters and time scales ranging from hours to weeks. They include shore-parallel bars (straight and crescentic) and transverse bars of different types. Furthermore, the present knowledge on the physical processes behind their formation and development is discussed., Peer Reviewed, Postprint (published version)

A new shoreline instability triggered by high-angle waves and leading to sand wave formation is investigated. In contrast with the well-known high angle wave instability, which involves both the surf and shoaling zones and develops at km-scale wavelengths, the present mechanism involves only the surf zone. The emerging morphology features up-current oriented bars coupled to a meandering of the longshore current. The dominant wavelengths scale with the surf zone width, Xb= O(102 m) and the characteristic growth times are O(1 day). The instability occurs only above a critical angle ¿30° in deep water and its maximum intensity is for ¿70°. It is associated to the gradients in longshore transport and, for wavelengths larger than Xb, the growth rate matches that of the instability predicted by the one-line approximation for an angle at breaking which is above the angle maximizing alongshore transport., Postprint (published version)

A number of morphodynamic models have been developed to simulate the dynamics of large-scale bedform patterns on the continental shelf. Most of the models are based on linear stability analysis and, therefore, only describe the characteristics of the bedforms at their formation. Apart from studying the principal formation mechanism, the models have take into account various processes (three dimensional flows, sediment sorting, wave stirring, different tidal constituents, etc) to describe the characteristics of the bedforms at specific locations. Exploration of the finite amplitude regime have also been made with simplified models. Future model developments are needed to explore long-term dynamics., Postprint (author's final draft)

A number of morphodynamic models have been developed to simulate the dynamics of large-scale bedform patterns on the continental shelf. Most of the models are based on linear stability analysis and, therefore, only describe the characteristics of the bedforms at their formation. Apart from studying the principal formation mechanism, the models have take into account various processes (three dimensional flows, sediment sorting, wave stirring, different tidal constituents, etc) to describe the characteristics of the bedforms at specific locations. Exploration of the finite amplitude regime have also been made with simplified models. Future model developments are needed to explore long-term dynamics., Postprint (author's final draft)

[ES] El objetivo de este trabajo se centra en el estudio y análisis del entorno costero mediante las líneas de costa extraídas en diferentes fechas y por diferentes técnicas como las imágenes de satélite LANDSAT o SENTINEL, imágenes las cuales se pueden descargar de forma gratuita, o datos tomados en campo como fotografías que se han usado para el control de las playas. La zona escogida será la costa portuguesa próxima a Lisboa, donde el amplio rango mareal de la zona supondrá un reto añadido en el proceso de evaluación y análisis de las líneas de costa. Los resultados obtenidos serán utilizados para identificar y asociar los diferentes agentes del moldeado litoral de la zona, además de estudiar el nivel de precisión de la extracción de la línea de costa en función de las condiciones varias que se puedan dar en el momento de la toma de esta (mareas, contrastes radiométricos, etc.). Durante el proyecto, el alumno tendrá la posibilidad de: aplicar diferentes técnicas y procesos propios de la teledetección u otras disciplinas de toma de datos georreferenciados (fotogrametría, topografía, etc.), desarrollar herramientas software para agilizar y automatizar los diferentes procesos del trabajo, utilización de diferentes herramientas SIG para el tratamiento de los datos, o la desarrollar trabajo orientados a la creación de una IDE (Infraestructura de Datos Espaciales) y geoportal básicos para la publicación libre de datos y resultados obtenidos., [EN] The objective of this work is to study and analyze the coastal environment using extracted shorelines from different dates and techniques like the satellite images of LANDSAT and SENTINEL, which are a free resource, or ground data like photographs that had been used to supervise the beaches. The selected area is the Portuguese coast nearby Lisbon, where the wide tidal range is an issue to be resolved in order to analyze properly the data acquired. The results will be used to identify the different shoreline processes of the zone and to study the level of precision of the shoreline extraction process in the different and various conditions that can take place during the acquisition of the data (tides, radiometric differences, etc.). The work offers the various opportunities like: apply and use different techniques from remote sensing or any other discipline related to the acquisition of georeferenced data (photogrammetry, surveying, etc.), develop any software in order to optimize the work phases, the use of GIS technology to treat and analyze the data, or work in order to the creation of a basic SDI (Spatial Data Infrastructure) to publish the data and the results obtained.

[ES] Debido al cambio climático, las costas sufren con mayor dureza las sacudidas del mar y las crecidas de los ríos. El calentamiento global provoca cambios en el sistema climático que afectan directamente a los procesos costeros y la delimitación de la línea de costa constituye un elemento fundamental en los procesos de análisis, gestión y planificación de la zona costera. En este trabajo, se presenta el análisis de la variación de la línea de costa por medio de imágenes Landsat (5 y 8) de la playa de El Puntal, en Ribamontán al Mar (Cantabria). Esta playa forma una flecha en la Bahía de Santander, de forma que el oleaje rompe en el lado norte y deja resguardado el lado sur. Para extraer la extracción de la línea de costa a nivel sub pixel de forma automática, se parte de un algoritmo desarrollado por el grupo de investigación de Cartografía GeoAmbiental y Teledetección (CGAT) de la Universidad Politécnica de Valencia. Dicho algoritmo, fue analizado en zonas de muy poco rango mareal, como es el mar Mediterráneo. Mediante este trabajo se analizan los resultados que se obtienen con el algoritmo en la playa analizada del Mar Cantábrico cuyo rango de marea astronómica medio es mesomareal (1-5m), factor discriminante para el procesado de datos. Los resultados obtenidos se componen de tres soluciones, cada una de ellas correspondiente a cada una de las bandas del infrarrojo que la imagen ofrece. Estos resultados se relacionan con la altitud del nivel del mar -que para cada fecha será distinta- mediante una correlación lineal. Para un mejor análisis, en la correlación se separaron los datos de las mareas ascendentes de las descendentes ya que cuando la marea baja, la tierra húmeda falsea los resultados porque tiene distinta reflectancia. Además, la línea de costa se ha partido en segmentos de diferentes longitudes -en función de su naturaleza dinámica- para ver cómo se comportaba la correlación a lo largo de la costa y de ese modo saber en qué sectores de la playa se com, [EN] The coast is modified by sea and river flooding impact, due to climate changes. Global warming causes changes in the climate system that directly affects in the process of analysis, planning and management of the coastal zone. In this study, the analysis of the coastline variation is implemented using Landsat (5 and 8) images from El Puntal beach in Ribamontán al Mar (Cantabria). This beach forms an arrow in the Bay of Santander, where the waves are breaking on the north side, leaving the south side protected to such effect. The shoreline delimitation is calculated using an algorithm developed by the Geo-Environmental Cartography and Remote Sensing group (CGAT) from the Polytechnic University of Valencia, which automatically extracts the coastline at sub pixel level. The algorithm was tested in areas with slight tidal range, such as the Mediterranean Sea. Through this work, the results obtained with the algorithm on analyze beach in the Cantabrian Sea which range tide is medium (1-5m) are analyzed. The results are composed by three solutions, corresponding to each of the bands provided by infrared the imagery. These outcomes are related to the altitude of the sea level ¿considering that for each date is different- by linear correlation analysis. For a better interpretation, the correlation of data of the rising tide was separated from the descending tide: with low tide, the wet ground distorts the results because it has different reflectance. In addition, the coastline has been divided into segments of different lengths -according to their dynamic nature- to see how the correlation behaved along the coast, and thus know which beach sectors performs better the line that has been processed with the algorithm.

[ES] El objetivo de este trabajo se centra en el estudio y análisis del entorno costero mediante las líneas de costa extraídas en diferentes fechas y por diferentes técnicas como las imágenes de satélite LANDSAT o SENTINEL, imágenes las cuales se pueden descargar de forma gratuita, o datos tomados en campo como fotografías que se han usado para el control de las playas. La zona escogida será la costa portuguesa próxima a Lisboa, donde el amplio rango mareal de la zona supondrá un reto añadido en el proceso de evaluación y análisis de las líneas de costa. Los resultados obtenidos serán utilizados para identificar y asociar los diferentes agentes del moldeado litoral de la zona, además de estudiar el nivel de precisión de la extracción de la línea de costa en función de las condiciones varias que se puedan dar en el momento de la toma de esta (mareas, contrastes radiométricos, etc.). Durante el proyecto, el alumno tendrá la posibilidad de: aplicar diferentes técnicas y procesos propios de la teledetección u otras disciplinas de toma de datos georreferenciados (fotogrametría, topografía, etc.), desarrollar herramientas software para agilizar y automatizar los diferentes procesos del trabajo, utilización de diferentes herramientas SIG para el tratamiento de los datos, o la desarrollar trabajo orientados a la creación de una IDE (Infraestructura de Datos Espaciales) y geoportal básicos para la publicación libre de datos y resultados obtenidos., [EN] The objective of this work is to study and analyze the coastal environment using extracted shorelines from different dates and techniques like the satellite images of LANDSAT and SENTINEL, which are a free resource, or ground data like photographs that had been used to supervise the beaches. The selected area is the Portuguese coast nearby Lisbon, where the wide tidal range is an issue to be resolved in order to analyze properly the data acquired. The results will be used to identify the different shoreline processes of the zone and to study the level of precision of the shoreline extraction process in the different and various conditions that can take place during the acquisition of the data (tides, radiometric differences, etc.). The work offers the various opportunities like: apply and use different techniques from remote sensing or any other discipline related to the acquisition of georeferenced data (photogrammetry, surveying, etc.), develop any software in order to optimize the work phases, the use of GIS technology to treat and analyze the data, or work in order to the creation of a basic SDI (Spatial Data Infrastructure) to publish the data and the results obtained.

[ES] El objetivo de este trabajo se centra en el estudio y análisis del entorno costero mediante las líneas de costa extraídas en diferentes fechas y por diferentes técnicas como las imágenes de satélite LANDSAT o SENTINEL, imágenes las cuales se pueden descargar de forma gratuita, o datos tomados en campo como fotografías que se han usado para el control de las playas. La zona escogida será la costa portuguesa próxima a Lisboa, donde el amplio rango mareal de la zona supondrá un reto añadido en el proceso de evaluación y análisis de las líneas de costa. Los resultados obtenidos serán utilizados para identificar y asociar los diferentes agentes del moldeado litoral de la zona, además de estudiar el nivel de precisión de la extracción de la línea de costa en función de las condiciones varias que se puedan dar en el momento de la toma de esta (mareas, contrastes radiométricos, etc.). Durante el proyecto, el alumno tendrá la posibilidad de: aplicar diferentes técnicas y procesos propios de la teledetección u otras disciplinas de toma de datos georreferenciados (fotogrametría, topografía, etc.), desarrollar herramientas software para agilizar y automatizar los diferentes procesos del trabajo, utilización de diferentes herramientas SIG para el tratamiento de los datos, o la desarrollar trabajo orientados a la creación de una IDE (Infraestructura de Datos Espaciales) y geoportal básicos para la publicación libre de datos y resultados obtenidos., [EN] The objective of this work is to study and analyze the coastal environment using extracted shorelines from different dates and techniques like the satellite images of LANDSAT and SENTINEL, which are a free resource, or ground data like photographs that had been used to supervise the beaches. The selected area is the Portuguese coast nearby Lisbon, where the wide tidal range is an issue to be resolved in order to analyze properly the data acquired. The results will be used to identify the different shoreline processes of the zone and to study the level of precision of the shoreline extraction process in the different and various conditions that can take place during the acquisition of the data (tides, radiometric differences, etc.). The work offers the various opportunities like: apply and use different techniques from remote sensing or any other discipline related to the acquisition of georeferenced data (photogrammetry, surveying, etc.), develop any software in order to optimize the work phases, the use of GIS technology to treat and analyze the data, or work in order to the creation of a basic SDI (Spatial Data Infrastructure) to publish the data and the results obtained.

[ES] El objetivo de este trabajo se centra en el estudio y análisis del entorno costero mediante las líneas de costa extraídas en diferentes fechas y por diferentes técnicas como las imágenes de satélite LANDSAT o SENTINEL, imágenes las cuales se pueden descargar de forma gratuita, o datos tomados en campo como fotografías que se han usado para el control de las playas. La zona escogida será la costa portuguesa próxima a Lisboa, donde el amplio rango mareal de la zona supondrá un reto añadido en el proceso de evaluación y análisis de las líneas de costa. Los resultados obtenidos serán utilizados para identificar y asociar los diferentes agentes del moldeado litoral de la zona, además de estudiar el nivel de precisión de la extracción de la línea de costa en función de las condiciones varias que se puedan dar en el momento de la toma de esta (mareas, contrastes radiométricos, etc.). Durante el proyecto, el alumno tendrá la posibilidad de: aplicar diferentes técnicas y procesos propios de la teledetección u otras disciplinas de toma de datos georreferenciados (fotogrametría, topografía, etc.), desarrollar herramientas software para agilizar y automatizar los diferentes procesos del trabajo, utilización de diferentes herramientas SIG para el tratamiento de los datos, o la desarrollar trabajo orientados a la creación de una IDE (Infraestructura de Datos Espaciales) y geoportal básicos para la publicación libre de datos y resultados obtenidos., [EN] The objective of this work is to study and analyze the coastal environment using extracted shorelines from different dates and techniques like the satellite images of LANDSAT and SENTINEL, which are a free resource, or ground data like photographs that had been used to supervise the beaches. The selected area is the Portuguese coast nearby Lisbon, where the wide tidal range is an issue to be resolved in order to analyze properly the data acquired. The results will be used to identify the different shoreline processes of the zone and to study the level of precision of the shoreline extraction process in the different and various conditions that can take place during the acquisition of the data (tides, radiometric differences, etc.). The work offers the various opportunities like: apply and use different techniques from remote sensing or any other discipline related to the acquisition of georeferenced data (photogrammetry, surveying, etc.), develop any software in order to optimize the work phases, the use of GIS technology to treat and analyze the data, or work in order to the creation of a basic SDI (Spatial Data Infrastructure) to publish the data and the results obtained.

[ES] Debido al cambio climático, las costas sufren con mayor dureza las sacudidas del mar y las crecidas de los ríos. El calentamiento global provoca cambios en el sistema climático que afectan directamente a los procesos costeros y la delimitación de la línea de costa constituye un elemento fundamental en los procesos de análisis, gestión y planificación de la zona costera. En este trabajo, se presenta el análisis de la variación de la línea de costa por medio de imágenes Landsat (5 y 8) de la playa de El Puntal, en Ribamontán al Mar (Cantabria). Esta playa forma una flecha en la Bahía de Santander, de forma que el oleaje rompe en el lado norte y deja resguardado el lado sur. Para extraer la extracción de la línea de costa a nivel sub pixel de forma automática, se parte de un algoritmo desarrollado por el grupo de investigación de Cartografía GeoAmbiental y Teledetección (CGAT) de la Universidad Politécnica de Valencia. Dicho algoritmo, fue analizado en zonas de muy poco rango mareal, como es el mar Mediterráneo. Mediante este trabajo se analizan los resultados que se obtienen con el algoritmo en la playa analizada del Mar Cantábrico cuyo rango de marea astronómica medio es mesomareal (1-5m), factor discriminante para el procesado de datos. Los resultados obtenidos se componen de tres soluciones, cada una de ellas correspondiente a cada una de las bandas del infrarrojo que la imagen ofrece. Estos resultados se relacionan con la altitud del nivel del mar -que para cada fecha será distinta- mediante una correlación lineal. Para un mejor análisis, en la correlación se separaron los datos de las mareas ascendentes de las descendentes ya que cuando la marea baja, la tierra húmeda falsea los resultados porque tiene distinta reflectancia. Además, la línea de costa se ha partido en segmentos de diferentes longitudes -en función de su naturaleza dinámica- para ver cómo se comportaba la correlación a lo largo de la costa y de ese modo saber en qué sectores de la playa se com, [EN] The coast is modified by sea and river flooding impact, due to climate changes. Global warming causes changes in the climate system that directly affects in the process of analysis, planning and management of the coastal zone. In this study, the analysis of the coastline variation is implemented using Landsat (5 and 8) images from El Puntal beach in Ribamontán al Mar (Cantabria). This beach forms an arrow in the Bay of Santander, where the waves are breaking on the north side, leaving the south side protected to such effect. The shoreline delimitation is calculated using an algorithm developed by the Geo-Environmental Cartography and Remote Sensing group (CGAT) from the Polytechnic University of Valencia, which automatically extracts the coastline at sub pixel level. The algorithm was tested in areas with slight tidal range, such as the Mediterranean Sea. Through this work, the results obtained with the algorithm on analyze beach in the Cantabrian Sea which range tide is medium (1-5m) are analyzed. The results are composed by three solutions, corresponding to each of the bands provided by infrared the imagery. These outcomes are related to the altitude of the sea level ¿considering that for each date is different- by linear correlation analysis. For a better interpretation, the correlation of data of the rising tide was separated from the descending tide: with low tide, the wet ground distorts the results because it has different reflectance. In addition, the coastline has been divided into segments of different lengths -according to their dynamic nature- to see how the correlation behaved along the coast, and thus know which beach sectors performs better the line that has been processed with the algorithm.

[ES] El objetivo de este trabajo se centra en el estudio y análisis del entorno costero mediante las líneas de costa extraídas en diferentes fechas y por diferentes técnicas como las imágenes de satélite LANDSAT o SENTINEL, imágenes las cuales se pueden descargar de forma gratuita, o datos tomados en campo como fotografías que se han usado para el control de las playas. La zona escogida será la costa portuguesa próxima a Lisboa, donde el amplio rango mareal de la zona supondrá un reto añadido en el proceso de evaluación y análisis de las líneas de costa. Los resultados obtenidos serán utilizados para identificar y asociar los diferentes agentes del moldeado litoral de la zona, además de estudiar el nivel de precisión de la extracción de la línea de costa en función de las condiciones varias que se puedan dar en el momento de la toma de esta (mareas, contrastes radiométricos, etc.). Durante el proyecto, el alumno tendrá la posibilidad de: aplicar diferentes técnicas y procesos propios de la teledetección u otras disciplinas de toma de datos georreferenciados (fotogrametría, topografía, etc.), desarrollar herramientas software para agilizar y automatizar los diferentes procesos del trabajo, utilización de diferentes herramientas SIG para el tratamiento de los datos, o la desarrollar trabajo orientados a la creación de una IDE (Infraestructura de Datos Espaciales) y geoportal básicos para la publicación libre de datos y resultados obtenidos., [EN] The objective of this work is to study and analyze the coastal environment using extracted shorelines from different dates and techniques like the satellite images of LANDSAT and SENTINEL, which are a free resource, or ground data like photographs that had been used to supervise the beaches. The selected area is the Portuguese coast nearby Lisbon, where the wide tidal range is an issue to be resolved in order to analyze properly the data acquired. The results will be used to identify the different shoreline processes of the zone and to study the level of precision of the shoreline extraction process in the different and various conditions that can take place during the acquisition of the data (tides, radiometric differences, etc.). The work offers the various opportunities like: apply and use different techniques from remote sensing or any other discipline related to the acquisition of georeferenced data (photogrammetry, surveying, etc.), develop any software in order to optimize the work phases, the use of GIS technology to treat and analyze the data, or work in order to the creation of a basic SDI (Spatial Data Infrastructure) to publish the data and the results obtained.

[ES] Debido al cambio climático, las costas sufren con mayor dureza las sacudidas del mar y las crecidas de los ríos. El calentamiento global provoca cambios en el sistema climático que afectan directamente a los procesos costeros y la delimitación de la línea de costa constituye un elemento fundamental en los procesos de análisis, gestión y planificación de la zona costera. En este trabajo, se presenta el análisis de la variación de la línea de costa por medio de imágenes Landsat (5 y 8) de la playa de El Puntal, en Ribamontán al Mar (Cantabria). Esta playa forma una flecha en la Bahía de Santander, de forma que el oleaje rompe en el lado norte y deja resguardado el lado sur. Para extraer la extracción de la línea de costa a nivel sub pixel de forma automática, se parte de un algoritmo desarrollado por el grupo de investigación de Cartografía GeoAmbiental y Teledetección (CGAT) de la Universidad Politécnica de Valencia. Dicho algoritmo, fue analizado en zonas de muy poco rango mareal, como es el mar Mediterráneo. Mediante este trabajo se analizan los resultados que se obtienen con el algoritmo en la playa analizada del Mar Cantábrico cuyo rango de marea astronómica medio es mesomareal (1-5m), factor discriminante para el procesado de datos. Los resultados obtenidos se componen de tres soluciones, cada una de ellas correspondiente a cada una de las bandas del infrarrojo que la imagen ofrece. Estos resultados se relacionan con la altitud del nivel del mar -que para cada fecha será distinta- mediante una correlación lineal. Para un mejor análisis, en la correlación se separaron los datos de las mareas ascendentes de las descendentes ya que cuando la marea baja, la tierra húmeda falsea los resultados porque tiene distinta reflectancia. Además, la línea de costa se ha partido en segmentos de diferentes longitudes -en función de su naturaleza dinámica- para ver cómo se comportaba la correlación a lo largo de la costa y de ese modo saber en qué sectores de la playa se com, [EN] The coast is modified by sea and river flooding impact, due to climate changes. Global warming causes changes in the climate system that directly affects in the process of analysis, planning and management of the coastal zone. In this study, the analysis of the coastline variation is implemented using Landsat (5 and 8) images from El Puntal beach in Ribamontán al Mar (Cantabria). This beach forms an arrow in the Bay of Santander, where the waves are breaking on the north side, leaving the south side protected to such effect. The shoreline delimitation is calculated using an algorithm developed by the Geo-Environmental Cartography and Remote Sensing group (CGAT) from the Polytechnic University of Valencia, which automatically extracts the coastline at sub pixel level. The algorithm was tested in areas with slight tidal range, such as the Mediterranean Sea. Through this work, the results obtained with the algorithm on analyze beach in the Cantabrian Sea which range tide is medium (1-5m) are analyzed. The results are composed by three solutions, corresponding to each of the bands provided by infrared the imagery. These outcomes are related to the altitude of the sea level ¿considering that for each date is different- by linear correlation analysis. For a better interpretation, the correlation of data of the rising tide was separated from the descending tide: with low tide, the wet ground distorts the results because it has different reflectance. In addition, the coastline has been divided into segments of different lengths -according to their dynamic nature- to see how the correlation behaved along the coast, and thus know which beach sectors performs better the line that has been processed with the algorithm.

[ES] El presente estudio pretende establecer de forma cuantitativa tendencias de avance/retroceso de la línea de costa, con el fin de poner de manifiesto la acreción/erosión de materiales sufrida en las playas de un tramo de la costa de Cullera (Valencia). En el estudio se ha tenido en cuenta la evolución de la línea de costa a medio-largo plazo, desde el 1956 hasta el año 2013. Las fuentes de información utilizadas han sido fotografías aéreas y ortofotografías. Las fotografías aéreas han sido digitalizadas y tratadas mediante técnicas fotogramétricas con el fin de obtener ortofotografías. El grado de precisión de las distintas fuentes de información es muy variable, y representa la principal dificultad en estudios retrospectivos de un fenómeno como el que nos ocupa. Para el análisis de las tendencias costeras se han delineado las líneas de costa de diez ortofotografías, mediante la herramienta, BeachTools, creada por el cuerpo de ingenieros del ejército de Estados Unidos. Esta herramienta permite la automatización del proceso de delineado. La gestión y análisis final de las líneas de costa obtenidas se realizó haciendo uso de un sistema de información geográfica. Se utilizará la extensión DSAS, cuyo entorno de trabajo es el software ArcGIS. Esta extensión fue desarrollada en los años noventa por la empresa NOAA, con el fin de crear una herramienta especializada en entornos de ámbito costero., [EN] The aim of this study is to quantitatively establish trends of advance and retreat of shoreline, to determinate the accretion/erosion of material taking place in a stretch of the coast of Cullera (Valencia, Spain). This study considers the shoreline evolution in a medium/long term, 57 years. The sources of information used were aerial photographs and orthophotos. Aerial photographs were digitized and processed using photogrammetric techniques, in order to obtain orthophotos. The degree of accuracy between the different sources is highly variable, and this is the main handicap to deal with in temporal studies of the phenomenon before us. The shoreline has been delineated from ten orthophotographs by using “BeachTools”, a tool developed by the US Army Corps of Engineers. This tool enables the process of delineation to be automatized. The final analysis and management of the obtained shoreline is performed by using a geographical information system. DSAS, an ArcGIS software extension, has been used. This extension was developed in the 90’s by the NOAA in the attempt to create a tool specialized in coastal environment., [CA] El present estudi pretén establir de forma quantitativa tendències d'avanç/retrocès de la línia de costa, a fi de posar de manifest l'acreció/erosió de materials patida en les platges d'un tram de la costa de Cullera (València). En l'estudi s'ha tingut en compte l'evolució de la línia de costa a mig-llarg termini, desde l´any 1956 fins l`any 2013. Les fonts d'informació utilitzades has sigut fotografies aèries i ortofotografíes. Les fotografies aèries han sigut digitalitzades i tractades per mitjà de tècniques fotogramétriques a fi d'obtindre ortofotografíes. El grau de precisió de les distintes fonts d'informació és molt variable, i es la principal dificultat a pugnar en estudis temporals d'un fenomen com el que ens ocupa. Per a l'anàlisi de les tendències costaneres s'han delineat les línies de costa de deu ortofotografíes, per mitjà de la ferramenta, BeachTools, creada pel cos d'enginyers de l'exercite dels Estats Units, que permet l'automatització del procés de delineat. La gestió i anàlisi final de les línies de costa obtingudes es va realitzar fent ús d'un sistema d'informació geogràfica. Es va utilitzar l'extensió DSAS, l'entorn de treball de la qual és per mitjà de programari ArcGIS. Esta extensió va ser desenrotllada en els anys noranta per l'empresa NOAA, a fi de crear una ferramenta especialitzada en entorns d'àmbit costaner.

[ES] El presente estudio pretende establecer de forma cuantitativa tendencias de avance/retroceso de la línea de costa, con el fin de poner de manifiesto la acreción/erosión de materiales sufrida en las playas de un tramo de la costa de Cullera (Valencia). En el estudio se ha tenido en cuenta la evolución de la línea de costa a medio-largo plazo, desde el 1956 hasta el año 2013. Las fuentes de información utilizadas han sido fotografías aéreas y ortofotografías. Las fotografías aéreas han sido digitalizadas y tratadas mediante técnicas fotogramétricas con el fin de obtener ortofotografías. El grado de precisión de las distintas fuentes de información es muy variable, y representa la principal dificultad en estudios retrospectivos de un fenómeno como el que nos ocupa. Para el análisis de las tendencias costeras se han delineado las líneas de costa de diez ortofotografías, mediante la herramienta, BeachTools, creada por el cuerpo de ingenieros del ejército de Estados Unidos. Esta herramienta permite la automatización del proceso de delineado. La gestión y análisis final de las líneas de costa obtenidas se realizó haciendo uso de un sistema de información geográfica. Se utilizará la extensión DSAS, cuyo entorno de trabajo es el software ArcGIS. Esta extensión fue desarrollada en los años noventa por la empresa NOAA, con el fin de crear una herramienta especializada en entornos de ámbito costero., [EN] The aim of this study is to quantitatively establish trends of advance and retreat of shoreline, to determinate the accretion/erosion of material taking place in a stretch of the coast of Cullera (Valencia, Spain). This study considers the shoreline evolution in a medium/long term, 57 years. The sources of information used were aerial photographs and orthophotos. Aerial photographs were digitized and processed using photogrammetric techniques, in order to obtain orthophotos. The degree of accuracy between the different sources is highly variable, and this is the main handicap to deal with in temporal studies of the phenomenon before us. The shoreline has been delineated from ten orthophotographs by using “BeachTools”, a tool developed by the US Army Corps of Engineers. This tool enables the process of delineation to be automatized. The final analysis and management of the obtained shoreline is performed by using a geographical information system. DSAS, an ArcGIS software extension, has been used. This extension was developed in the 90’s by the NOAA in the attempt to create a tool specialized in coastal environment., [CA] El present estudi pretén establir de forma quantitativa tendències d'avanç/retrocès de la línia de costa, a fi de posar de manifest l'acreció/erosió de materials patida en les platges d'un tram de la costa de Cullera (València). En l'estudi s'ha tingut en compte l'evolució de la línia de costa a mig-llarg termini, desde l´any 1956 fins l`any 2013. Les fonts d'informació utilitzades has sigut fotografies aèries i ortofotografíes. Les fotografies aèries han sigut digitalitzades i tractades per mitjà de tècniques fotogramétriques a fi d'obtindre ortofotografíes. El grau de precisió de les distintes fonts d'informació és molt variable, i es la principal dificultat a pugnar en estudis temporals d'un fenomen com el que ens ocupa. Per a l'anàlisi de les tendències costaneres s'han delineat les línies de costa de deu ortofotografíes, per mitjà de la ferramenta, BeachTools, creada pel cos d'enginyers de l'exercite dels Estats Units, que permet l'automatització del procés de delineat. La gestió i anàlisi final de les línies de costa obtingudes es va realitzar fent ús d'un sistema d'informació geogràfica. Es va utilitzar l'extensió DSAS, l'entorn de treball de la qual és per mitjà de programari ArcGIS. Esta extensió va ser desenrotllada en els anys noranta per l'empresa NOAA, a fi de crear una ferramenta especialitzada en entorns d'àmbit costaner.

[ES] El presente estudio pretende establecer de forma cuantitativa tendencias de avance/retroceso de la línea de costa, con el fin de poner de manifiesto la acreción/erosión de materiales sufrida en las playas de un tramo de la costa de Cullera (Valencia). En el estudio se ha tenido en cuenta la evolución de la línea de costa a medio-largo plazo, desde el 1956 hasta el año 2013. Las fuentes de información utilizadas han sido fotografías aéreas y ortofotografías. Las fotografías aéreas han sido digitalizadas y tratadas mediante técnicas fotogramétricas con el fin de obtener ortofotografías. El grado de precisión de las distintas fuentes de información es muy variable, y representa la principal dificultad en estudios retrospectivos de un fenómeno como el que nos ocupa. Para el análisis de las tendencias costeras se han delineado las líneas de costa de diez ortofotografías, mediante la herramienta, BeachTools, creada por el cuerpo de ingenieros del ejército de Estados Unidos. Esta herramienta permite la automatización del proceso de delineado. La gestión y análisis final de las líneas de costa obtenidas se realizó haciendo uso de un sistema de información geográfica. Se utilizará la extensión DSAS, cuyo entorno de trabajo es el software ArcGIS. Esta extensión fue desarrollada en los años noventa por la empresa NOAA, con el fin de crear una herramienta especializada en entornos de ámbito costero., [EN] The aim of this study is to quantitatively establish trends of advance and retreat of shoreline, to determinate the accretion/erosion of material taking place in a stretch of the coast of Cullera (Valencia, Spain). This study considers the shoreline evolution in a medium/long term, 57 years. The sources of information used were aerial photographs and orthophotos. Aerial photographs were digitized and processed using photogrammetric techniques, in order to obtain orthophotos. The degree of accuracy between the different sources is highly variable, and this is the main handicap to deal with in temporal studies of the phenomenon before us. The shoreline has been delineated from ten orthophotographs by using “BeachTools”, a tool developed by the US Army Corps of Engineers. This tool enables the process of delineation to be automatized. The final analysis and management of the obtained shoreline is performed by using a geographical information system. DSAS, an ArcGIS software extension, has been used. This extension was developed in the 90’s by the NOAA in the attempt to create a tool specialized in coastal environment., [CA] El present estudi pretén establir de forma quantitativa tendències d'avanç/retrocès de la línia de costa, a fi de posar de manifest l'acreció/erosió de materials patida en les platges d'un tram de la costa de Cullera (València). En l'estudi s'ha tingut en compte l'evolució de la línia de costa a mig-llarg termini, desde l´any 1956 fins l`any 2013. Les fonts d'informació utilitzades has sigut fotografies aèries i ortofotografíes. Les fotografies aèries han sigut digitalitzades i tractades per mitjà de tècniques fotogramétriques a fi d'obtindre ortofotografíes. El grau de precisió de les distintes fonts d'informació és molt variable, i es la principal dificultat a pugnar en estudis temporals d'un fenomen com el que ens ocupa. Per a l'anàlisi de les tendències costaneres s'han delineat les línies de costa de deu ortofotografíes, per mitjà de la ferramenta, BeachTools, creada pel cos d'enginyers de l'exercite dels Estats Units, que permet l'automatització del procés de delineat. La gestió i anàlisi final de les línies de costa obtingudes es va realitzar fent ús d'un sistema d'informació geogràfica. Es va utilitzar l'extensió DSAS, l'entorn de treball de la qual és per mitjà de programari ArcGIS. Esta extensió va ser desenrotllada en els anys noranta per l'empresa NOAA, a fi de crear una ferramenta especialitzada en entorns d'àmbit costaner.

The Random Forest algorithm was used to classify 86 Wide Fine Quadrature Polarized RADARSAT-2 scenes, five Landsat 5 scenes, and a Digital Elevation Model covering an area approximately 81,000 km2 in size, and representing the entirety of Dease Strait, Coronation Gulf and Bathurst Inlet, Nunavut. The focus of this research was to assess the potential to operationalize shoreline sensitivity mapping to inform oil spill response and contingency planning. The impact of varying the training sample size and reducing model data load were evaluated. Results showed that acceptable accuracies could be achieved with relatively few training samples, but that higher accuracies and greater probabilities of correct class assignment were observed with larger sample sizes. Additionally, the number of inputs to the model could be greatly reduced without impacting overall performance. Optimized models reached independent accuracies of 91% for seven land cover types, and classification probabilities between 0.77 and 0.98 (values for latter represent per-class averages generated from independent validation sites). Mixed results were observed when assessing the potential for remote predictive mapping by simulating transferability of the model to scenes without training data.

Sandy coasts are characterized by a number of rhythmic patterns like, amongst others, shoreline undulations or sandwaves at a kilometric scale. One hypothesis for their formation is that high angle waves (large incidence angle with respect to shore normal) could induce an instability of the shoreline (Ashton et al., 2001). More recently, a scaling for their wavelength has also been proposed (van den Berg et al., 2014). The existing studies rely mainly on modelling but quantitative field tests are lacking. We aim at investigating how both the formation hypothesis of these shoreline undulations and the theoretical scaling do fit with nature at a global scale. The first step, which is the goal of this paper, is to set up the methodology by analyzing the Atlantic African coast as test site. First, based on global databases, shoreline wavelength LS, wave characteristics (obliquity ¿W and wavelength ¿W) and mean shoreface slope ß are determined. Then the wave obliquity is confronted with the presence of shoreline undulations. Finally the values of the ratio ßLS / ¿W are estimated and discussed in comparison with the estimate of van den Berg et al. (2014). It is found that the correlation between shoreline sandwave occurrence and wave obliquity is very good, allowing the identification of 5 new potential unstable shoreline stretches, whereas the results on the scaling are not conclusive and deserve further investigations., Postprint (published version)

Km-scale shoreline sand waves have been studied with a quasi two dimensional model (Q2D-morfo model) and with observations from a populated coastal zone in Yucatán (México) with frequent human interventions. The model was modified to improve the physics in the case of large amplitude shoreline sand waves that develop due to the high angle wave instability (HAWI). The modified version of the model can better reproduce the formation of large-amplitude shoreline sand waves, compared with the original model. Shorelines of Yucatán, from 2004 to 2012, were digitized and analyzed. Although undulations can be observed, they do not exhibit clear migration or growth, an indication of being in the limit of instability, in accordance with the results of the model, Peer Reviewed, Postprint (published version)

The beach of Calella, north of Barcelona, in the Catalan coast, features a series of shoreline sand waves with wavelengths ranging from 700 to 1400 m that match with similar undulations in the -5 m bathymetric line. Historical satellite images from 2002 till 2010 show that these undulations slightly change in time. The wave climate on that stretch of the Catalan coast has a large proportion of waves from the E-NE and from the SW, i.e., with high angles with respect to shore normal rending the shoreline potentially unstable. Here we show that those sand waves might be due to that instability. Model results, both Linear Stability Analysis and nonlinear time evolution, show that the shoreline is nearly at the threshold for instability and that the emergent wavelengths are roughly consistent with the observed ones., Postprint (published version)

This Coastal and Hydraulics Engineering Technical Note (CHETN) documents the initial morphologic evolution of the Perdido Key, FL, swash-zone berm based on beach-nearshore profile, sediment samples, and nearshore wave data collected during the first six months after berm construction. The US Army Corps of Engineers (USACE), Mobile District, dredged the navigation channel at Pensacola Pass, FL, from November 2011 to January 2012 and placed the 520,000 cubic yards (yd3) of dredged sand as a swash-zone berm nearshore of Perdido Key, FL. Beach quality sands are a valuable resource within the coastal zone in maintaining regional sediment balance. Compared to a typical beach fill (or direct beach placement), nearshore berm placement (in this case a swash-zone berm) has advantages of being less costly with more lenient regulatory restrictions on sediment type and monitoring requirements (Hands and Allison 1991; McLellan and Kraus 1991). The Perdido Key berm was designed to be an active berm that would quickly mobilize sediments in the energetic swash zone. The goal was to beneficially use maintenance dredged material to nourish the littoral environment adjacent to Pensacola Pass, and to have an immediate impact on the narrow subaerial beach. This CHETN documents the initial morphological evolution of the Perdido Key swash-zone berm placement based on analysis of beach-nearshore profiles, sediment samples, and nearshore wave data. The eastern portion of Perdido Key, including the present study area, was nourished in 1985 and 1989 (Dean et al. 1995). The 1985 beach nourishment was constructed to a berm height of +10.3 ft NAVD88, whereas the 1989 beach nourishment had a constructed berm height of +4.3 ft NAVD88 (Dean et al. 1995; Browder and Dean 2000). The 1989 nourishment also included a nearshore berm placed at roughly -22 ft NAVD88 with a crest height of roughly 5.7 ft. The 2012 Perdido Key artificial berm was placed west of Pensacola Pass (Figure 1)., The original document contains color images.

Large beach cusps with wavelengths O(200m), sometimes termed mega-cusps, were measured along 18km of the Southern Monterey Bay coastline from October 2004 to April 2005 to investigate the cuspate shoreline response to rip current systems. Monterey Bay is a unique location for the study of rip current systems, which has with well defined rips that are present all year long, a large dune erosional rate, and incident wave energy that is primarily shore-normal with a large alongshore gradient. Contours of the coastline were extrapolated from the surveys using an all-terrain vehicle equipped with Kinematic GPS. Cusp spacing was inferred from the data using a zero up-cross technique and found to be O(230m) for low wave energy beaches and O(250m) for high wave energy beaches. Migration rates of the cusps were found to be 1-5m/day owing to the quasi-uniform erosion of the dune system. Cusps were found to be semi-permanent features with length scales dependant upon the local wave climate., http://archive.org/details/cuspateshoreline109451924, Approved for public release; distribution is unlimited.

Low-lying reef islands formed on the rim of atolls in Kiribati appear threatened by the impacts of anticipated sea-level rise. The reef islands around Tarawa Atoll are composed of unconsolidated carbonate sediments, particularly the tests of benthic foraminifera. This thesis aims to examine the morphological development of these reef islands over a range of time scales. To achieve this aim, the following tasks were carried out: investigation of the topography and the accumulated volumes of sediment sequestered on the reef islands, reconstruction of the evolution of selected reef islands and determination of whether or not rates of sediment supply have been reduced and, examination of historical shoreline changes. The topography of the reef islands was described, based on a digital terrain model (DTM) derived from photogrammetry. Using geographical information systems (GIS), it is estimated that approximately 60 million m3 of sediment has accumulated on the reef islands since the mid Holocene. Most reef islands show a morphology that comprises an oceanward ridge that is generally 2 to 3 m, and in some places greater than 4 m, above mean sea level (MSL). Many reef islands have a low-lying central depression. More than 50% of the land area lies below 2.4 m above MSL. The lagoonward ridge is generally 1.5 to 2.0 m above MSL. Based on the distribution of elevation classes, the hypsometry of reef islands has been examined. Most reef islands (24 of 36) show an S-shaped form with a large proportion of the reef island being in the lowest elevation range. Ten reef islands, typically the smallest are classified as platforms, with little variation in elevation across them. Only two reef islands show a more concave form with a significant proportion of low-lying areas. The evolution of three reef islands was investigated by dating individual foraminifera, Amphistegina, using radiocarbon dating by Accelerator Mass Spectrometry (AMS). A program of paired AMS and amino-acid racemis

Low-lying reef islands formed on the rim of atolls in Kiribati appear threatened by the impacts of anticipated sea-level rise. The reef islands around Tarawa Atoll are composed of unconsolidated carbonate sediments, particularly the tests of benthic foraminifera. This thesis aims to examine the morphological development of these reef islands over a range of time scales. To achieve this aim, the following tasks were carried out: investigation of the topography and the accumulated volumes of sediment sequestered on the reef islands, reconstruction of the evolution of selected reef islands and determination of whether or not rates of sediment supply have been reduced and, examination of historical shoreline changes. The topography of the reef islands was described, based on a digital terrain model (DTM) derived from photogrammetry. Using geographical information systems (GIS), it is estimated that approximately 60 million m3 of sediment has accumulated on the reef islands since the mid Holocene. Most reef islands show a morphology that comprises an oceanward ridge that is generally 2 to 3 m, and in some places greater than 4 m, above mean sea level (MSL). Many reef islands have a low-lying central depression. More than 50% of the land area lies below 2.4 m above MSL. The lagoonward ridge is generally 1.5 to 2.0 m above MSL. Based on the distribution of elevation classes, the hypsometry of reef islands has been examined. Most reef islands (24 of 36) show an S-shaped form with a large proportion of the reef island being in the lowest elevation range. Ten reef islands, typically the smallest are classified as platforms, with little variation in elevation across them. Only two reef islands show a more concave form with a significant proportion of low-lying areas. The evolution of three reef islands was investigated by dating individual foraminifera, Amphistegina, using radiocarbon dating by Accelerator Mass Spectrometry (AMS). A program of paired AMS and amino-acid racemis

Low-lying reef islands formed on the rim of atolls in Kiribati appear threatened by the impacts of anticipated sea-level rise. The reef islands around Tarawa Atoll are composed of unconsolidated carbonate sediments, particularly the tests of benthic foraminifera. This thesis aims to examine the morphological development of these reef islands over a range of time scales. To achieve this aim, the following tasks were carried out: investigation of the topography and the accumulated volumes of sediment sequestered on the reef islands, reconstruction of the evolution of selected reef islands and determination of whether or not rates of sediment supply have been reduced and, examination of historical shoreline changes. The topography of the reef islands was described, based on a digital terrain model (DTM) derived from photogrammetry. Using geographical information systems (GIS), it is estimated that approximately 60 million m3 of sediment has accumulated on the reef islands since the mid Holocene. Most reef islands show a morphology that comprises an oceanward ridge that is generally 2 to 3 m, and in some places greater than 4 m, above mean sea level (MSL). Many reef islands have a low-lying central depression. More than 50% of the land area lies below 2.4 m above MSL. The lagoonward ridge is generally 1.5 to 2.0 m above MSL. Based on the distribution of elevation classes, the hypsometry of reef islands has been examined. Most reef islands (24 of 36) show an S-shaped form with a large proportion of the reef island being in the lowest elevation range. Ten reef islands, typically the smallest are classified as platforms, with little variation in elevation across them. Only two reef islands show a more concave form with a significant proportion of low-lying areas. The evolution of three reef islands was investigated by dating individual foraminifera, Amphistegina, using radiocarbon dating by Accelerator Mass Spectrometry (AMS). A program of paired AMS and amino-acid racemis

Anglès: This study consists on the analysis of detached breakwaters and their influence on the shoreline response. Their importance to protect coastal strips against erosion and the difficulty to determine their complete behaviour and their relevant parameters, are the main aspects treated along the whole paper. First of all, a general overview of coastal dynamics is depicted. Second, a description of the actual coastal protection state is made, highlighting the reasons why coastal engineers have been focused on the problems and solutions related to coastline response for the last years. A comparison between the different measures that can be applied is realised in order to define their strong and weak points and to introduce offshore breakwaters as a valid and broadly applied option. The third item deals with detached breakwaters characteristics and influence on morphodynamic processes, and is the previous step to the exposure of the main topic of the thesis: the design guidelines. A subdivision between submerged and emerged breakwaters is made in order to achieve a better understanding of the process behind and around the structures, and highlight the relative difference of behaviour. General design guidelines, basically in form of geometric indicators, are defined and classified depending on their shoreline response description, for instance discerning between salient, tombolo and limited response. In order to determine the current validity of these indicators, and other parameters that seem to be relevant and were not taken into consideration, an overview of real reported cases is exposed. Comparisons between the results observed in the real cases with the guidelines and the numerical calculations realized on a first stage are described, stressing the complexity of the design of detached breakwaters.

The growth of megacusps as shoreline instabilities is investigated by examining the coupling between wave transformation in the shoaling zone, long-shore transport in the surf zone, cross-shore transport, and morphological evolution. This coupling is known to drive a potential positive feedback in case of very oblique wave incidence, leading to an unstable shoreline and the consequent formation of shoreline sandwaves. Here, using a linear stability model based on the one-line concept, we demonstrate that such instabilities can also develop in case of low-angle or shore-normal incidence, under certain conditions (small enough wave height and/or large enough beach slope). The wavelength and growth time scales are much smaller than those of high-angle wave instabilities and are nearly in the range of those of surf zone rhythmic bars, O(102 − 103 m) and O(1 − 10 days), respectively. The feedback mechanism is based on: (1) wave refraction by a shoal (defined as a cross-shore extension of the shoreline perturbation) leading to wave convergence 26 shoreward of it, (2) longshore sediment flux convergence between the shoal and the shoreline, resulting in megacusp formation, and (3) cross-shore sediment flux from the surf to the shoaling zone, feeding the shoal. Even though the present model is based on a crude representation of nearshore dynamics, a comparison of model results with existing 2DH model output and laboratory experiments suggests that the instability mechanism is plausible. Additional work is required to fully assess whether and under which conditions this mechanism exists in nature., Postprint (author’s final draft)

The shoreline stabilization adjacent to the public access boat ramp in the Packery Channel basin has been damaged in two separate events. For the shoreline damage at the boat ramp bulkhead, toe scour is the likely mechanism for failure. Typical sources of hydrodynamic forcing that can lead to toe erosion include storm currents, locally generated storm waves, and offshore storm waves propagating into the basin through Packery Channel. Quantitative analysis of storm induced wind generated waves and currents eliminated them as possible causes of the damage. However, photographic and movie evidence indicate the presence of low-frequency low-amplitude waves propagated into the basin and impacted the boat ramp. The Coastal System Model (CMS) was used to simulate a range of these low-frequency low-amplitude waves and the results demonstrated that these waves could produce sufficient flows in the vicinity of the boat ramp shoreline to cause the damage. Subsequent modeling was used to develop design criteria for additional shoreline stabilization., Published in the Journal of Coastal Research, Special Issue n59 p150-155, 2011. Prepared in cooperation with URS Corporation, Tallahassee, FL.

The morphological changes caused by storm events in two Barcelona beaches were recorded using video monitoring techniques during the period 2001–2006. Changes in shoreline position and configuration and submerged bar position and shape were analyzed during the 25 major storm events that occurred during the study period. Beach responses to storms were grouped into three categories: shoreline advance or retreat (including rotation), sandbar migration and/or configuration change (linear or crescentic shape) and formation of megacusps. This work provides examples of the differential adaptation of both beaches to the same storm and of some unexpected morphological responses of both beaches. The response of the beach to storm events is not straightforward because wave conditions are not the only relevant parameter to be considered. In particular, in such embayed beaches it is crucial to take into account their specific morphodynamic configuration prior to the storm., Peer Reviewed, Postprint (published version)