Page 12 - Pasanisi_alii_2015
P. 12

coastline geometry and seabed
                                                                                morphology and, as expected
                                                                                from what discussed above, more
                                                                                intense hydrodynamic conditions
                                                                                are observed at Cala  Azzurra
                                                                                compared to Lido Burrone.
                                                                                From    nearshore    circulation
                                                                                patterns, a general transport
                                                                                toward the eastern ends of both
                                                                                sites can be noticed. This seems
                                                                                to suggest a certain potential
                                                                                sediment  supply to the Cala
                                                                                Azzurra eastern bay and to the
                                                                                Lido Burrone beach, where, in
                                                                                fact, permanent  emerged beach
                                                                                can be observed.  The above
            FIGURE 17   Simulation of nearshore wave propagation at Cala Azzurra. Incident wave   observation, however, takes into
                    conditions correspond to morphological waves for SE and SW sectors                               Research & development
                    at 15 m depth                                               account only average  incident
                                                                                wave conditions and is not to be
                                                                                considered exhaustive of the
                                                                                complex  sediment dynamics of
                                                                                study area.


                                                                                Conclusions


                                                                                In-situ activities and model studies
                                                                                performed during the project
                                                                                provided a detailed knowledge of
                                                                                coastal morphology and dynamics
                                                                                of Cala Azzurra and Lido Burrone
                                                                                coastal sites.
                                                                                The main results can be
                                                                                summarized as follows:
                                                                                1.  Both sites present a quite
            FIGURE 18   Simulation of nearshore wave propagation at Lido Burrone. Incident wave   complex bathymetry.
                    conditions correspond to morphological waves for SE and SW sectors    2.  Limitedly to surveyed areas, an
                    at 15 m depth
                                                                                   overall stability of submerged
                                                                                   beach was observed, with
           depicted in Figure 19 and Figure 20 in terms of time-     little bathymetric variations among different surveys.
           averaged surface elevation, whilst Figure 21 and Figure   A clear seasonal regime of beach profiles was not
           22 illustrate the  wave-driven nearshore circulation   noticeable from  survey  data,  even if  this  aspect
           currents.                                             should be better clarified by further investigation
           At both sites, offshore-directed return currents can   on sea bottom geology and coverage.
           be noticed in the middle of the nearshore area.    3.  Results of  the  hydrodynamic study are  consistent
           Nearshore currents are strongly affected by the       with field observations.




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