Department of Civil and Building Engineering, and Architecture, Università Politecnica delle Marche, 60131 Ancona, Italy
L. Soldini
Department of Civil and Building Engineering, and Architecture, Università Politecnica delle Marche, 60131 Ancona, Italy
C. Lorenzoni
Department of Civil and Building Engineering, and Architecture, Università Politecnica delle Marche, 60131 Ancona, Italy
A. Mancinelli
Department of Civil and Building Engineering, and Architecture, Università Politecnica delle Marche, 60131 Ancona, Italy
Abstract. In the recent years attention has been paid to the beach protection by means of soft and hard defenses. Along the Italian coasts of the Adriatic Sea, sandy beaches are the most common landscapes and around 70 % of the Marche-Region coasts (central Adriatic), is protected by defense structures. The longest free-from-obstacle nearshore area in the Region includes the beach of Senigallia, characterized by a multiple barred beach, frequently monitored during the last decades. The bathymetries surveyed in 2006, 2010, 2011, 2012 and 2013 show a good adaptation of the beach to the Dean-type equilibrium profile, though a strong short-/medium-term variability of the wave climate has been observed during the monitored periods. This suggests a slight influence of wave forcing on the long-term profiles, which seems to only depend on the sediment size. Further, the medium-term dynamics of the submerged bars and their geometric features have been related to the wave climate collected by a wave buoy located 40 km off Senigallia during the analyzed temporal windows. An overall interpretation of the complete dynamics, i.e. hydrodynamics (buoy data), sediment characteristics (equilibrium-profile A parameter) and morphodynamics (bathymetric surveys), suggests that the wave climate is fundamental for the morphodynamic changes of the beach in the medium term: waves coming from NNE/ESE are characterized by a larger/smaller steepness and induce seaward/shoreward bar migration, as well as bar smoothing/steepening. Moving southward, the bar dimension increases, while the equilibrium profile suggests a decrease of the sediment size in the submerged beach, this probably due to the presence of both harbor jetty and river mouth North of the investigated area.
Received: 30 Jun 2015 – Discussion started: 10 Aug 2015
The characterization of bar geometry and dynamics in an unprotected sandy beach of the Middle Adriatic is here presented. Coupling of climate and bathymetric surveys suggests that time periods dominated by waves coming from NNE, i.e. almost perpendicular to the coast, promote seaward migration, partial destruction and smoothing of the submerged bars. Conversely, periods dominated by waves from ESE, i.e. angled w.r.t. shoreline, induce shoreward migration, regeneration and steepening of the bars.
The characterization of bar geometry and dynamics in an unprotected sandy beach of the Middle...