Regional model estimation of seasonal and interannual variability of circulation and volume transport in the Sicily Channel.

The Sicily Channel is a key area for the dynamics of the Mediterranean Sea, as it crucially contributes regulating the exchange of water masses, as well as of biogechemical characteristics between the Western and Eastern Mediterranean basins. This research focuses on investigating the dynamics of the Sicily Channel, particularly its seasonal variability, studied using a high-resolution regional model (Regional Ocean Modeling System – ROMS) and in situ data (moorings equipped with ADCPs) referring to the period from 2010 to 2019. During winter, the surface circulation is mainly influenced by the wind, which fosters the formation of mesoscale variability, whereas it is mainly regulated by the topography of the Strait in summer. The deep circulation is mainly regulated by the Strait's bathymetric constraints and by the remote variability of intermediate waters, which reflect the large-scale variability of the basin. These processes lead to an increase in transport during the winter months, peaking in January-February, while a general decrease occurs in the summer.