ABSTRACT
ABSTRACT: In this paper some evidences on the 3D finite element hydrodynamic model SHYFEM development are presented to simulate the interaction lagoon-open sea processes. A study has been performed to identify the rate of impact of each forcing (tides, wind, freshwater, heat fluxes) in simulating hydrodynamic processes in coastal areas. A particular interest is for phenomena in proximity of rivers and inlets, such as the three inlets connecting the Venice Lagoon with the Adriatic Sea (Lido, Malamocco and Chioggia Inlets). The model has been checked by applying a test case from Chao and Boicourt (1986), reproducing the freshwater input of a river in an idealized basin. The test case permitted to assess the 3D behavior of water masses, in terms of advective, barotropic and baroclinic pressure gradients and diffusive contributions on circulation. In the test case baroclinic pressure gradient terms in the momentum equations are computed explicitly, while temperature and salinity gradients are applied as forcings. The real case run, applied to the Venetian Lagoon connected to theAdriatic Sea, permitted to conclude that two additional forcings are important in proximity of inlets: wind stress and tidal cicles. As a future step, the thermohaline coastal circulation will be investigated, even introducing to the real case run the temperature and salinity initial conditions to compute the baroclinic terms.
