Valentina Agresti
Department of Physics and Astronomy, University of Bologna, Bologna, Italy
Now at: Ricerca sul Sistema Energetico – RSE, Milano, Italy

The study of tides and their interactions with the complex dynamics of the Mediterranean Sea represents a crucial and important challenge in ocean modeling. Both the equilibrium tide and the Atlantic tides contribute to tidal propagation in this semi-enclosed Sea hence the right modeling of the Gibraltar Strait dynamic is of primary importance. In particular, we show that a minimum horizontal resolution of 1/24° is required in order to simulate tides properly. Other factors influencing tidal simulation are an accurate bathymetry and a careful nesting on a global tidal model. The strength of this Mediterranean tidal configuration, implemented in NEMO model, is its capability to simulate from the synoptic scale to the mesoscale, an essential characteristic to understand the dynamics of the Mediterranean Sea and the role that tides play. This study confirms that the interaction of the barotropic tide with the topography of the Strait of Gibraltar generates an internal tidal variability which produces an enhancement of vertical mixing at the entrance of the Mediterranean Sea. Consequently saltier and colder waters are found on the surface layer in most part of the Western Mediterranean basin and higher salinity characterizes the Modified Atlantic water entering in the Eastern basin, when tides are prescribed. Tides are also responsible for the intensification of different gyres, especially in the southern part of the basin, where mesoscale and semi-permanent gyres are present.

Note: The seminar will be held at the CMCC premises in Bologna, Viale Berti Pichat 6/2 – Meeting Room (Second Floor).

Working language: English