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Adaptation of port infrastructures to climate change and sea level rise effects is highlighted as a key field among transportation systems' lines of action for adaptation, given their highly exposed location in coastal areas and position as critical nodes in logistic chains and local, regional and national economies. The present work proposes an adaptation assessment framework that, based on a high-resolution compound climate risk assessment, identifies the main threats that climate change may pose to port performance, defines a set of optimized adaptation measures and characterizes constraints for implementation, and finally evaluates the applicability and effectiveness of these measures under diverse climate scenarios and different time frames. The framework is applied in a study case located in the northern coast of Spain. It is shown that the proposed methodology enables port managers and planners to develop tailor-fitted adaptation plans, providing tools to make them coherent with actual and future uncertain climate conditions. • The paper develops a novel framework to prepare climate change adaptation plans for port and coastal infrastructures. • It identifies the main needs and limitations for adaptation of port infrastructures based on a compound CC risk assessment. • It identifies and optimizes a set of adaptation measures, considering measure combinations, based on risk-reduction criteria. • It assesses the adaptation options' effectiveness in reducing climate risk for different scenarios and time horizons. • The framework has been applied and validated for a case study located on the Atlantic coast in Spain. [ABSTRACT FROM AUTHOR]

In this paper, an innovative framework is introduced for assessing the impact of climate change on coastal structures, with a primary emphasis on modeling future climate conditions. The framework encompasses several key components: the development of a new climate emulator to facilitate multivariate extreme value analysis; a hybrid statistical–numerical wave propagation strategy; and the integration of a novel compound modeling approach specific to coastal structure sites. These advancements are designed to effectively manage multiple climate scenarios and models within the context of high uncertainty. The methodology is applied and validated for a coastal structure located on the Mediterranean coast in Spain. Focusing on compound wave and sea-level events, the projections indicate an increase in the frequency and severity of extreme conditions, exacerbating coastal impacts such as wave overtopping. For instance, the present-day 500-year coastal flooding level would be associated with a return period of 50 years by mid-century under a stabilization scenario and would be further reduced to 25 years under a high-emission global warming scenario, resulting in important consequences for structure performance if no adaptation is implemented. • Develops a framework for assessing the impact of climate change on coastal structures. • It develops a new climate emulator to facilitate multivariate extreme value analysis. • It encompasses a hybrid statistical–numerical wave propagation strategy. • It integrates a novel compound modeling approach specific to coastal structures sites. • It has been applied and validated for a coastal structure in Spain. [ABSTRACT FROM AUTHOR]

The Catalan coast, as most of the developed Mediterranean coastal zone, can be characterized as a high-risk area to the impact of storms due to the large concentration of values together with the dominance of eroding shorelines. In consequence, any long-term coastal management scheme must include a risk analysis to permit decision makers to better allocate resources. This can be done in a nested approach in which hotspots are first identified along the coast at a regional scale and secondly, they are further analysed to produce dedicated risk reduction strategies. In this work, we apply the methodology developed within the RISC-KIT project for identifying and analysing coastal hotspots in the Catalan coast as a test for applying it to Mediterranean conditions. Obtained results show that this methodology is very efficient in identifying hotspots of storm-induced flooding and erosion at a regional scale. The adoption of the response approach resulted in the direct assessment of the hazards' probability distributions, which allowed for the selection of the severity of the hotspots to be identified. When a given coastal stretch behaves as a hotspot for both hazards, it is identified as a very highly-sensitive area to storm impacts. In the study area, the Tordera Delta possesses this condition of very high “hotspotness.” This has been demonstrated by the large and frequent damages suffered by the site during the past decades. The paper analyses different aspects related to the risk management of this area, including stakeholder actions. [ABSTRACT FROM AUTHOR]

An accurate estimation of the historical harbour wave agitation is fundamental for many practical applications, such as port downtime analyses. In practical harbour agitation studies, usually based on numerical propagations from offshore wave climate towards a harbour (wave downscaling), the accuracy in defining the outer wave climate has an impact on wave agitation estimations, especially important for multimodal wave climates. In this paper, several strategies for wave agitation downscaling are presented based on different existing approaches with different accuracy levels for: a) wave downscaling method; b) definition of outer spectral waves. The accuracy/performance of each approach is evaluated by applying, and comparing them with multi-point instrumental data from a field campaign, in a real scenario (Africa basin, Las Palmas Port, Spain) where the multimodality of waves, in addition to the agitation effects from port structures in the far-field, clearly determines the final accuracy of the in-port wave agitation. Improved results have been achieved with the most sophisticated/accurate strategies proposed. A comparative analysis of the advantages, limitations, uncertainty and CPU effort of each one, allows to suggest the preferable strategy, in each situation/context, for practical port wave agitation studies. • Six different wave downscaling strategies for practical wave agitation studies in harbours are presented. • A strongly multimodal outer-harbour wave climate is analyzed, resulting in an important influence on in-port wave agitation. • An accurate real-shaped characterization of forcing spectral wave climate is achieved, through a dynamic wave downscaling. • An uncertainty reduction in wave agitation prediction, approximately by half, is obtained presenting an accuracy ranking. • Instrumental data-based uncertainty is quantified, and a comparative analysis suggests the best-strategy to be followed. [ABSTRACT FROM AUTHOR]

Bay beaches are common coastal landforms along the world's coastlines and have frequently been used as equilibrium coastal systems to mitigate erosion problems and stabilize coasts. Throughout the literature, several formulae can be found to obtain the static equilibrium planform (SEP) of such beaches on the leeward sides of single protruding headland structures. However, equations used to define SEP behind breakwater gaps are rare and based on a limited number of studies, especially when the obliquity angle (β) is large. This paper proposes a new formula for modelling the SEP of bay beaches that includes cases with planform shapes characterized by large obliquity angles (β > 75°) for which the SEP is almost quasi-semicircular. The formula represents a general form of the parabolic bay shape equation (PBSE) with modified coefficients to alter the planform's curvature to be quasi-semicircular, mimicking the behavior of such bays in nature. The coefficients are expressed as functions of both the obliquity angle (β) and the curvature-adjustment angle (φ), which was determined based on field observations of the best-fitting SEP of 26 bay beaches with (β > 75°) along the coasts of Spain, Portugal and Brazil. Additionally, 32 beach cases characterized by smaller obliquity angles (β < 70°) were included in the derivation of the curvature adjustment angle, which was expressed as a function of (β). The model showed good results in modelling the SEP, with an RMSE of 0.90° obtained when estimating the planform's curvature-adjustment angle (φ) to obtain quasi-semicircular planform shapes for the prototype cases, confirming its utility as a valuable tool for engineering applications. • Static equilibrium planforms (SEPs) characterized by large obliquity angles are modelled. • A new formula was derived to plot the (SEP) of bay beaches behind gaps when (β > 75°). • A curvature-adjustment angle is used to alter the SEP's curvature based on field cases. • The SEP is quasi-semicircular for pocket beaches behind breakwater gaps when (β > 75°). • The curvature-adjustment angle is directly proportional to the obliquity angle (β). [ABSTRACT FROM AUTHOR]

This paper investigates the impact of the bridge-pilling modifications on the tidal flow at the strait of a human-altered mesotidal estuary (Cádiz Bay, Spain). The analysis was accomplished by combining (1) field data of current velocities in a cross-section close to the pile of a recently built bridge, and (2) hydrodynamics results from the calibrated and tested DELFT3D numerical model on the study site. The analysis was focused on bridge piling effects at intratidal scale during neap and spring tides. Semidiurnal (D2), quarti-diurnal (D4) and sixth-diurnal (D6) bands were examined. The ratio of quarter-diurnal to semidiurnal amplitudes (D4/D2) is largest (¿1) near the bottom of the channel due to friction, and the ratio D6/D2 is largest (¿1.5) close to the pile and in the shallowest part of the cross-section, due to internal asymmetry and tidal advective accelerations. Comparing neap and spring tides, the most marked asymmetries are found in the latter. These asymmetries occur around the wake of the pile, alternating from flood to ebb. The location of the bridge pile causes a decrease in the amplitude of D2 (50%), and a phase lag in the tidal wave of 30 min. The D6 amplitude increases up to almost 100% due to distortion of the tidal wave induce by the wake created at the pile. Moreover, the pile reduces about 1 m the depth where the pycnocline is observed. Additionally, the pile can be considered as an obstacle for the sediment flux. These effects can be extrapolated to similar infrastructures, such as wind or wave energy farms, that can potentially modify the estuarine dynamics. • Tidal flow is modified by a bridge piling in an estuary. • The M2 tidal amplitude is reduced up to 50% near the pile. • The pile causes a 30-min phase lag in the pile wake. • The sixth-diurnal tidal band increases up to 100%. • The center of the pycnocline is deepened by 1 m. [ABSTRACT FROM AUTHOR]

Abstract: Insurance against natural perils such as flooding can be considered a significant element in coastal management. It can offer not only much-needed support to accelerate economic and social recovery following a disaster (coastal resilience) but also contribute to impact limitation by using pricing or restrictions on availability of coverage to discourage new development in hazard-prone areas. Insurance can affect the redistribution of damage costs across the population and through time, both in the short and long term. Policies of damage reduction are linked to mitigation measures for the properties (old or new buildings) by changing the depth–damage relationship while the long-run risk impacts could affect the overall damage function by discouraging new buildings in high risk areas. This paper will provide an overview of the main theoretical perspectives on insurance in flood risk management. Four different European contexts will be analysed. Data are derived from surveys and interviews conducted in France, United Kingdom, Italy and Spain. [Copyright &y& Elsevier]

Abstract: A standard assumption in coastal engineering is that the porosity of natural beach sand (non-cohesive) is 40%. However, is this assumption correct for all beach sand? This paper proposes an accurate and simplified method to assess changes in sand porosity after beach nourishment by means of in-situ density surveys through a nuclear densimeter. This novel application has been applied to different beaches in the southwest of Spain according to the tidal range, grain size and beach morphology in several terms. General results show that sand porosities range from 25.6% to 43.4% after beach nourishment works. This research can be considered a support tool in coastal engineering to find shifting sand volumes as a result of sand porosity variability after beach nourishment and later marine influence. [Copyright &y& Elsevier]

Abstract: The concept of equilibrium plan form and equilibrium profile has been widely used as an engineering tool in order to design beach nourishment projects. The scope of this paper is to further explore this “equilibrium beach” concept in crenulated bays, as a long-term tool for beach nourishment projects. The proposed methodology is based on and combines the static equilibrium plan and profile for long-term analysis. This methodology includes a modified equilibrium plan form, which is able to define the orientation of the local wave front in the diffracting point, and also to locate the downcoast starting point of the static equilibrium beach from which the parabolic plan form of is valid. This methodology permits the application of any equilibrium profile formulation. An example of the application of this methodology and long-term formulations to the design of the Spanish nourishment project of Poniente Beach (Gijón) is presented. Ten years after its construction, the beach has still got a static equilibrium and remains pretty close to the predicted equilibrium beach in plan and profile. [Copyright &y& Elsevier]

Abstract: A background knowledge of marine dynamics helps harbour managers to control pollution and to manage dredging and traffic operations. This contribution studies the hydrodynamic conditions within Bilbao Harbour, which is enclosed by the Nervión Estuary (in the Basque Country, Spain). The results obtained from hydrographical surveys are compared with numerical simulations obtained using the Regional Ocean Modelling System (ROMS). Hydrodynamic modelling was carried out to determine the inner harbour currents for a specific period in which data were available. Then, numerical experiments were designed in order to quantify the importance of different driving mechanisms in the harbour hydrodynamics. The results show that, in addition to the strong tidal influence on water circulation, the wind forcing and freshwater discharge also have a non-negligible influence on the currents. The computational domain is complex due to the presence of harbour infrastructures (i.e. breakwaters and piers). As a result, topographic eddies are therefore observed in the results. The freshwater influence of the Nervión river can also be observed in residual currents. This paper presents an improvement to the application of numerical modelling to a complex geometry domain, contributing to our understanding of the behaviour of the marine systems in meso-tidal harbours. This can be used to deal with harbour engineering and management problems. [Copyright &y& Elsevier]

Abstract: The paper compares the wave hindcast in the Western Mediterranean sea using the reanalysis wind fields from HIPOCAS and ERA-40 from ECMWF for November 2001. The study has concentrated on the Mediterranean coast of Spain where there are known difficulties with the wind and wave modelling. Two winter storms have been compared. The main differences between the significant wave heights using the ERA-40 reanalysis (ECMWF) and HIPOCAS reanalysis winds were observed to increase when moving southwards in the geographical domain at the offshore locations. Systematic negative biases of Hs were obtained with the ERA-40 data at all the coastal locations analyzed, whereas positive biases are typical for the HIPOCAS reanalysis. For offshore and coastal locations when using the ERA-40 data the Hs biases increased moving to South, while this pattern was not so clear for the HIPOCAS data. The inconsistencies in the comparisons of modelled waves against measurements seem to be associated with the quality of the wind fields. [Copyright &y& Elsevier]

This paper presents a new approach to statistically characterize and simulate the wave climate under storm conditions. The methodology includes the joint selection of the parameters that identify storm events (significant wave height threshold, minimum storm duration and minimum interarrival time between consecutive storms) by means of hypothesis testing on the distribution functions of the number of storm events and the elapsing time between storms, providing an improved characterization of the parameters that define storm events. The main wave variables and their temporal dependence are characterized by non-stationary mixture distribution functions and a vector autoregressive model. This allows to adequately reproduce the random temporal evolution of storm events, crucial for the study of damage progression in maritime structures without the use of predefined geometries. The long-term time series of storm events and calm periods is obtained using copula functions which analyze the joint dependence of storm duration and interarrival time for separate climate intervals. The model is applied to hindcast data at a location of the Mediterranean sea close to the Granada coast in Spain to show its ability to reproduce wave storm conditions accounting for the time variability of the storminess. An example of application, using a large number of simulations and a damage progression model in a maritime structure, is presented. • A statistical model for long-term simulation of extreme events is developed. • The methodology allows for the rigorous selection of the parameters that define a storm event. • The model accurately reproduces the multivariate storm events and their temporal evolution. • A case study in the Mediterranean coast of Spain is presented as a validation of the methodology. [ABSTRACT FROM AUTHOR]