Frequently exposed to natural agents such as waves, wind, tides, storm activity, seasonal changes and anthropogenic agents, coastal areas are tangibly high energy environments and therefore subject to considerable dynamics. In order to mitigate and reduce the impacts on these areas, different types of coastal protection systems can be implemented. Rockwalls and breakwaters are the most ordinary structures and even if used precisely for coastal protection, these flexible structures can in turn be damaged or ineffective over time. Therefore, like the monitoring of coastal areas in terms of execution frequency and accuracy, the measurement of changes over time of these structures, in particular after significant events, can allow to carry out an economic maintenance service before a serious occurrence and costly damage. However, given the rapid evolution of the preservation state of coastal areas and protection structures, it is therefore essential to plan an equally frequent, practical and accurate structural-coastal monitoring. On the other hand, their accessibility can sometimes be dangerous or uncomfortable such as to compromise operations in the field. In this work, the application of two close-range detection techniques competitor, i.e. from the Terrestrial Laser Scanner and from Remote Piloted Aircraft Systems, aimed at the generation of three-dimensional reconstructions of a protection structure, was analyzed. By performing a cloud-to-cloud comparison, interesting considerations have been obtained on the precision that can be achieved and on the technical limits deriving from the two methodologies. Considering the economy and practicality of use, if used correctly, a Remote Piloted Aircraft Systems supported by a suitable geo-referencing and an optimized data processing, can produce accurate and coherent 3D reconstructions as those derivable from the Terrestrial Laser Scanner. Finally, the results obtained by merging the point clouds generated from the two different techniques were evaluated in order to identify any advantages in the structural maintenance of the systems.

HIDRALERTA is a forecast and early warning system for coastal and port regions capable of predicting emergency situations, as well as carrying out risk assessment. The system concentrates on evaluating wave overtopping and flooding scenarios. It uses offshore sea-wave and wind forecast data, as well as tide data, as input to determine wave overtopping at specific locations. The calculation of the mean overtopping discharge over a structure is made through artificial neural network tools and/or empirical formulae, which are able to define the spatial distribution of the flow behind the structure. The HIDRALERTA system is composed of four modules developed in Open Source Web Technology, mainly using the Python Language. The Warning System can be configured and adapted for specific scenarios. The system has been successfully tested for the Port and Bay of Praia da Vitória, Terceira Island, Azores, Portugal, and is now under development and being implemented at the ports of Madalena do Pico and S. Roque do Pico. This paper describes the work carried out to date on the system and its application to these two ports in the Pico Island, Azores.

Coastal and port structures represent a large economic investment for society during their lifetime. Therefore, there is a need for proper coastal planning and management. In order to do that, wave and current loads must be considered by determining their level where the coastal structure should resist, otherwise they may suffer extensive damage due to these environmental loads. In this study, a new frame of performance design for coastal structures which includes climate change effects is discussed as a future design methodology. Performance-Based Design considers a coastal structure's performance determined by the amount of damage. In other words, the structure which is exposed to wave impacts should maintain its serviceability by limiting its damage, so that, its economic, operational, life-safety and environmental impacts are acceptable to the owner. The importance of this method is that it provides a possibility to the owners to work with the engineer in order to establish desired and acceptable levels of wave loads as the basis for a design. Also, it gives an opportunity to the engineer to design structures with their foreknown behavior against the design wave load levels. These performance objectives include two specifications; the hazard levels to which the structure is to be designed, and the permissible amount of damage when the structure is subjected to these hazard levels. This paper aims to explain the performance-based design methodology by giving the deformation-based reliability design for breakwaters and its applicability to the stability design. Since the methodology requires information on the extreme wave-height distribution near the design site, the effect of wave climate change on the performance-based design is investigated.

Dune restoration projects that integrate vegetation efforts with natural, sustainable, and soft solutions have become increasingly popular in coastal communities. Eco-restored dunes have high aesthetic value and are likely to be more resilient to near-surface wind effects and/or minor storms events. However, environmental-friendly restoration strategies still lack scientific insight from systematic research and the role of eco-restoration in dune erosion resistance and resilience has not yet been rigorously investigated. The question is: how can we optimize eco-friendly solutions in dune ecosystem restoration to maximize the resistance and resilience of coastal dunes against erosion from wind, wave, and storm surge attack? The present paper proposes an innovative colloidal silica-based consolidation technique for coastal sand dunes. A special focus is placed on the description of the experience gained from two pilot field studies started in Salento coastal area, in the south of Italy. The preliminary observations clearly show that mineral colloidal silica increases the mechanical strength of non-cohesive sediments allowing the adopted solution to reduce the volume of dune erosion and the dune scarp retreat rate, thus improving the resistance and resilience of the dune system. Besides furthering our knowledge of coastal erosion, the results of these and future studies will be of value to coastal managers and policy makers responsible for dune restoration projects.

Transitional waters are ecosystems of important naturalistic value and enjoy different forms of protection. They are often subject to the threat of pollution phenomena due to anthropic activities and therefore objects of research for the choice of good monitoring, control and management practices. This study deals with the environmental analysis, conducted with water quality measurement campaigns and subsequent analysis of the data collected, of two lagoons in southern Italy, the Lesina lagoon and the Varano lagoon. These fall into the category of transitional waters sensu the Directive 2000/60/EC. The anthropic pressures and their impacts were evaluated in order to assess the environmental quality objectives stated by the mentioned European Directive. As a result, this study showed a non-critical state of the lagoons, but they will certainly be kept under observation.

This study presents the benefits of the application of multivariate techniques for the hazard assessment of a heavily polluted marine ecosystem. The study area, named Mar Piccolo, near Taranto city (Southern Italy), is a shallow marine basin located nearby an industrial compromised area, declared by the national government as Contaminated Site of Environmental Interest (SIN) due to the presence of long-lasting large industrial settlements that have severely impacted the marine environment. Besides the anthropogenic pressures, the marine basin is characterized by high productivity of several species at different trophic levels of the food chain, that confers to the bottom sediments an unusually high organic matter content. The latter is even enhanced by the presence of freshwater springs in the marine basin. The dynamism of the ecosystem demands for advanced evaluation tools for its correct characterisation. Multivariate ANOVA allied by Hierarchical Clustering are applied in this research to provide a readable picture of the quality status of the sediments, aiming at identifying different loading factors and getting insights into their simultaneous effects. The innovative approach adopted circumvents inefficient time-consuming procedures, usually required by the conventional univariate analyses of each parameter selected for sediment characterisation. A comprehensive hazard assessment was possible thanks to a clear graphical representation of the hazard distribution that supported the identification of the hazard controlling factors, confirming the efficiency of the adopted approach. The tools proposed herein can thus be recommended for the decision makers in investigating and interpretation of the quality status of complex polluted marine eco-systems.

Between the evening of October 23^rd and the evening of October 24^th 2017, a sea storm hit the city of Bari, along the Adriatic coast, in the south of Italy, causing widespread damages. Due to the absence of direct observations of wave characteristics, the present paper is aimed to (i) compare the development of the occurred sea storm as hindcasted by '84 method with the predictions by atmosphere-ocean numerical models and satellite observations and (ii) estimate the most reliable value of the significant wave height, H_s, at the peak of the sea storm, with its associated return period. As a result, the '84 showed the better agreement with the satellite observations in determining the value of H_s at the peak of the sea storm, compared with the predictions by more sophisticated atmosphere-ocean numerical models. In particular, the obtained value of H_s, equal to 6.58 m, makes the investigated sea storm an exceptional event.

This paper aims to evaluate spatiotemporal variability of the mean sea level pressure trends over the Black Sea using the gridded 40-year (1979-2018) reanalysis mean sea level pressure data from two different datasets. These datasets are the European Centre for Medium-Range Weather Forecasts ERA-Interim with a spatial resolution of 0.25° and temporal resolution of six hours, and the National Centers for Environmental Prediction/Climate Forecast System Reanalysis with a spatial resolution of 0.5° and temporal resolution of one hour. Data from both databases show that the mean sea level pressure tends to decrease towards the recent years over the entire Black Sea. The long-term averages of mean sea level pressure reflect the spatial variability over the Black Sea with much lower pressures in the eastern part of the Black Sea than that on the western side. The long-term variation is more intense in the eastern part of the Black Sea. Sea Level Anomaly over the Black Sea, spanning 26 years between 1993 and 2018, was analyzed using satellite altimetry data. It was found that there is a high Sea Level Anomaly where the mean sea level pressure is low, described by an inverted barometer response. The 39-year long Sea Surface Temperature Anomaly data (1981-2018) indicate the rising tendency in sea surface temperature towards recent years in the entire Black Sea. An inverse relationship is found between North Atlantic Oscillation index and sea surface temperature anomaly. On a seasonal scale, mean sea level pressure in winter (high-pressure system) is larger than that in summer (low-pressure system). Our analyses show that mean sea level pressure tends to decrease, sea surface temperature anomaly and sea surface temperature anomaly tends to increase in recent years over the Black Sea.

Sediment deposition is an issue affecting many rivers. To oppose it, sediment withdrawals are often used. However, this practice can trigger further problems in river and coastal sections but, on the other hand, periodic removal of deposited sediments can reduce flooding risk. Also, these sediments can be used for beach nourishment. Therefore, before carrying out a sediment withdrawal, it is necessary to analyze the whole basin to evaluate the consequences for the sediment balance. This paper describes a methodology to evaluate the effects of river sediment withdrawals through a case study on the Amendolea River, a torrential river in southern Italy. In particular, the methodology is divided into three main phases. The first phase was developed with GIS software in order to perimeter and to morphometrically characterize the river basin and its hydraulically and sedimentologically homogeneous sub-basins. The second phase was developed using the HEC-HMS software in order to evaluate the hydrological balance of the basin and its sub-basins. The last phase was developed using the HEC-RAS software (through the SIAM model) in order to identify the areas in erosion, in deposition and in equilibrium. Moreover, through this model is possible to identify the sections where sediments can be withdrawn, and to estimate the possible morphological river changes due to withdrawals. In this case study, the sediments will be taken from the sections where the bottom has elevations near or above those of adjacent lands, such as to increase the flooding risk. Sediment withdrawals will be taken without eroding the bottom and at a distance from the river banks that does not unstabilize them.

Finally, the methodology described in this paper is based on the joint use of various open source software and can be used in any other river with hydrological regime similar to the Amendolea River.

Steel slags are side products of iron and steel industry and are suitable for a variety of applications. In the present paper, the assessment of the hazard associated with steel slags used as harbor piers backfilling material was performed. The analyses were conducted on 64 samples (soil and groundwater) collected in 17 sites located in one of the piers of Taranto city (South Italy), a highly industrialized area, where steel slags have been used in the past as backfill material. The obtained data were compared to the national threshold levels and International Indexes (I_geo) for assessing anthropogenic impacts. The first comparative analysis revealed that only vanadium in soil and aluminum in groundwater, associated with high pH values in both matrixes (soil and groundwater) resulted of high concern. Nevertheless, I_geo values and the coupling of comparative analysis with multivariate techniques Principal component analysis and Hierarchical Cluster Analyses revealed that also Sb, Pb, Cr and Zn concentration have an extremely high hazard degree. All analyses confirm the impact of steel slags on contaminant leaching processes due to the strong alkaline nature of their leachates and the presence of strong relationship between metal mobility and other physical-chemical parameters related to the peculiar environmental context. These findings suggest that the use of such materials, albeit economically recommended, should be adopted under severe monitoring of all parameters that could promote the mobility of metals and other contaminants.

Maritime works often require sediment handling activities such as dredging and disposal, to maintain harbors and channels, nourish sandy beaches as well as to carefully remove and relocate contaminated materials from the bottom of estuarine and coastal areas. Such operations often lead to an increase in the concentration of suspended sediments in water columns, which in turn causes adverse effects on water quality and aquatic lives. Minimizing these detrimental impacts require designing such maritime works with care, by paying attention to the geometry of areas affected by the sediment resuspension. Numerical modeling has been recognized as a valuable tool to help designers and contractors to optimize such sediment handling works. In obtaining such, one of the most challenging aspects to be tackled is the estimation of the settling velocity of the fine-grained mixture that results from sediment resuspension. These settling velocities are affected by a phenomenon known as flocculation. In this paper, the concept of non-local interacting particles was used to formulate a one-dimensional model for the flocculation phenomenon. Also, a (deterministic) particle transport equation was formulated to reproduce the settling behavior of suspended sediments in a settling column. The proposed model was solved numerically. The simulation results provide an understanding of the mechanisms of flocculation and highlight how flocculation influences floccule-settling velocities and concentration percentages of sediments that remain in suspension.

Coastal soil erosion can be recognized as the most alarming environmental issue since, causing shoreline retreat, reduces the area available for plant habitat survival, highly influencing their health status, and, consequently, limiting their ability in beach front properties protection. A deep knowledge of vegetation changes is required to identify the proper strategy to be adopted to face soil erosion problems in coastal areas. Therefore, the current paper is aimed to quantitatively examine the spatio-temporal changes suffered by the vegetation in the coastline of Siponto in Apulia Region (Southern Italy) covering a time period of about forty years. LANDSAT images from 1975, 2006, 2011 and 2018 were collected, atmospherically corrected and, finally, processed to generate binary classification maps of vegetation by applying the Composite Vegetation Index, a novel index based on the interpolation of Red, Green and Near-Infrared bands, suitable for catching both cellular and metabolic features of vegetation. Then, the generated binary classification maps were compared using the Vegetation Index Differencing technique, a post-classification change detection technique. The results showed an increase in vegetation extension cover and density overall the entire examined period. That phenomenon appeared more and more prominent between 1975 and 2006, where an increment of vegetated areas extension of about 88% were registered. Combining of the novel vegetation index, developed ad-hoc in the current research, and Vegetation Index Differencing approach shows promising results in vegetation classification and comparison over the time. Indeed, the method allows the fast vegetation extraction, great processing time saver. Nevertheless, spatial resolution of Landsat Images limits the classification of small and low-density vegetated areas. Therefore, future work should plan to test the proposed approach at a more detailed scale.