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The analysis of shoreline changes is very important for coastal planning and management. In territories such as Calabria (Italy), characterized by significant anthropogenic pressures and various eroded coasts, the knowledge of the shoreline changes, and the factors that influence them, is necessary for management and planning of coastal areas. In fact, shoreline position is one of the most important indicators of coastal dynamics. From this point of view recent advances in remote sensing and GIS techniques allow to estimate with great precision the shoreline changes over the years. The paper analyzes the shoreline changes near the mouth of the Sant'Agata River (Reggio Calabria, Italy), carried out through the comparison of various cartography data. Furthermore, the paper analyzes the main factors influencing the coastal dynamics in order to identify possible correlation between these factors and the shoreline changes. The analysis of these factors shows that, in this case study, the rainfall regime has a considerable influence on shoreline change. The methodology described in this paper is particularly useful for better understanding the factors that most influence the coastal balance and, therefore, is applicable to many contexts which are similar to the Sant'Agata river mouth.

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The wave climate is highly variable temporally and spatially, depending mainly on the atmospheric conditions and on fetch extensions. Wave climate is one of the main causes of coastal erosion processes, together with anthropogenic pressure and with coastal and river sedimentary balance. Therefore, a detailed spatial and temporal knowledge of wave climate is very important in managing coastal areas and in planning coastal defense works. This paper describes an analysis of the wave climate carried out along the Calabrian coasts in over 50 areas, each of them covering an average of 15 km of coastline. For each area, over 40 years of wave data were analyzed to calculate over 20 parameters, representative of annual and seasonal average and maximum wave conditions. The large number of areas is related to the geomorphological and climatic complexity of Calabria. This analysis mainly highlighted that the two Ionian and Tyrrhenian coasts are very different from the wave climate point of view. Indeed, the Ionian coast is heavier in ordinary wave conditions, while the Tyrrhenian coast is heavier in extreme wave conditions.

Contractions and expansions are common features in various types of pipeline systems. The purpose of this study is to investigate the influence of a sudden cross-section change on transient pressure waves. The paper presents laboratory data and numerical calculations of pressure oscillations during the valve-induced water hammer in serially connected steel pipes. Five different variants of experiments were conducted which included recording pressure changes at the downstream end of the pipeline system. The more sections with different diameters there are connected in series, the more complex the transient wave recorded is. Laboratory data indicate a significant influence of individual pipeline sections on the final course of pressure oscillations. Transient equations were solved using the explicit MacCormack scheme. In order to numerically simulate water hammer in pipe series, the improved junction boundary condition was established. It involves assigning two sets of values, which describe flow parameters, to the connection node thus causing it to act as two separate nodes. The numerical model was calibrated with the unsteady friction factor. The derivation of equations that take into account a sudden change in diameter in the connected pipes allowed the reproduction of the wave nature of the water hammer phenomenon, results were satisfactory as compared to experimental data. Numerical model correctly reproduced pressure wave interactions and pressure amplitudes.