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A boldly innovative soft engineering intervention, comprising an unprecedented 21.5 Mm3 sand nourishment known as the Sand Engine, has recently been implemented in the Netherlands. The Sand Engine nourishment is a pilot project to test the efficacy of loc

Nowadays coastal zones are densely populated areas all over the world and, consequently, part of the coasts’ changes can be attributable to humans. The Spanish coast is a clear example of the previous theory as it constitutes a very popular touristic destination in Europe due to the presence of ecologically valuable areas and for offering the demanded three “s”: Sun, sea and sand. However, the large number of people inhabiting the coast increases the pressure on coastal systems and their resources. Climate change and its subsequent sea-level rise put these zones and their living communities at risk, as several studies have predicted potential impacts of erosion and retreat of coastlines. In view of the situation, the increasing awareness of the future situation of the coasts has motivated a large number of vulnerability assessments over the world. These assessments are an essential tool to provide an efficient management, a part from being crucial when optimising the available resources. The actual situation of economic crisis reduces the availability of resources and therefore, a proper optimisation is very important. In this work a vulnerability assessment is carried out along the Spanish coastline. An adaptation of the Coastal Vulnerability Index is applied for the first time at a large (national) scale. Other applications in Spain have been at a regional scale, and this one has the aim to provide a general overview for future management and adaptation. The quantification of the index consists of the evaluation of six variables according to their vulnerability degree that is quantified in a 1 to 5 scale (from very low vulnerability to very high vulnerability). The proposed modification of the index suggest new methodologies to assess certain variables in order to better characterise its contribution to vulnerability and adapt to local conditions. When it comes to the variable sea-level rise, it has been widely predicted and the IPCC (Intergovernmental Panel on Cl, La costa és un sistema molt dinàmic sotmès a un gran varietat de factors geomorfològics i oceanogràfics que hi provoquen canvis a diferents escales. A l’actualitat, les zones costaneres concentren gran part de la població mundial i, en conseqüència, també hi exerceixen canvis significants. La costa espanyola és un clar exemple d’aquest fenomen ja que constitueix un destí turístic de referència a nivell europeu per l’oferta de zones de gran valor ecològic i les tres “s” sol· licitades pels estiuejants: “sun, sea and sand”. No obstant, l’afluència de turistes accentua el creixement urbanístic a la costa i, en conseqüència, incrementa la pressió sobre els sistemes costaners i els seus recursos. El canvi climàtic i la seva lligada pujada del nivell del mar posen en alerta aquests sistemes i les comunitats que els ocupen, ja que les prediccions deixen entreveure impactes potencials d’erosió i inundació, entre d’altres. Davant d’aquestes previsions, la creixent preocupació pel futur de les costes d’arreu del món està causant un increment en el nombre d’estudis de vulnerabilitat costanera. L’elaboració d’aquests estudis és una eina fonamental per garantir una eficient gestió i planificació de les costes, a part de ser decisiva a l’hora de optimitzar els recursos disponibles. Aquest últim punt constitueix un factor bàsic avui en dia ja que l’actual crisi econòmica restringeix la disponibilitat de recursos de forma considerable i, per tant, aquests s’han de prioritzar i optimitzar el màxim possible. En aquesta tesina es duu a terme un estudi de vulnerabilitat al llarg de la costa espanyola per mitjà de l’aplicació de l’Índex de Vulnerabilitat Costanera. Aquest índex ha estat aplicat prèviament a nivell regional dins l’estat espanyol, però és en aquest document quan s’aplica per primera vegada a nivell de tot l’estat. Com s’ha esmentat, aquest estudi és essencial per a gestionar els recursos de l’estat a nivell administratiu. La quantificació d’aquest índex consisteix en l’av

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 scientific objective of the work is to develop a quantitative understanding of the processes that control the formation of marine stratigraphy over time scales ranging from decades to millennia. This work is based on the creation and application of a series of advanced numerical models representing the dynamics of marine sediment transport, sediment accumulation, morphological change and feedback between the evolving sea floor and the hydrodynamic forcing. Field data are used to both force the models and to verify their results. The models are used to diagnose complex systems and as predictive tools., The original document contains color images. Prepared in collaboration with the Geology Department, Florida State University, Tallahassee, Delft University of Technology, Delft, The Netherlands, and Marine and Coastal Management, WL/Delft Hydraulics, Delft, The Netherlands.