Short-term evolution of the Budoni beach on NE Sardinia (Italy)

Dynamics and evolution trend in Budoni beach are described. The beach (long about 4km) is composed of fine to gravelly quarz sand, few seasonal lagoons are developed behind the dunes. Short- term variations have been periodically monitored since October 09. Sedimentary and hydrodynamic characteristics were studied. Short- term evolution was tested using topo-bathymetric digital models, derived from data acquired in 3 different field; models of wave motion and hydrodynamics were created using Delft3D software. The results obtained from these models (wave ray direction, deep current distribution, structure and surfzone dynamics) allowed to visualize the response of beach to wind/waves stress, forced from NE, E, SE (wind intensity 18m/s, 10m/s). Gregale and Sirocco are the winds that generate the widest surfzone, the currents created by the these win- ds cause mainly longshore transportation in the early hours of the meteo-marine event. The beach shows an homeostatic behavior characteristics typical of balanced systems.