A high-resolution modelling study of the circulation along the Campania coastal system, with a special focus on the Gulf of Naples

Abstract

A high-resolution modelling study of the circulation along the Campania coastal system (CCS) in the southern Tyrrhenian Sea is presented. The area includes three adjacent, semi-enclosed shallow basins (the gulfs of Gaeta, Naples and Salerno) facing the open deep sea, and represents an ideal site for investigating relevant dynamical processes of general interest in coastal oceanography. A Campania Regional sigma-coordinate Ocean Model (CROM) has been implemented in this region, with a 1/144° resolution; nesting with an operational circulation model covering the whole Tyrrhenian Sea with a 1/48° resolution is performed. Forcing is provided by surface momentum, heat, and freshwater fluxes computed from the non-hydrostatic SKIRON/Eta atmospheric modelling system outputs. A winter and a summer period of the reference year 2009 are analyzed in detail. The relative importance of the flow induced by remote large-scale currents through topographic interactions and of that induced locally by the wind are found to vary, even over a weekly time scale, in all of the three gulfs; the Gulf of Salerno appears to be the location where remote and local forcing are more often competing. An analysis of the high frequency variability shows that, besides the current changes induced by the typical mid-latitude atmospheric synoptic variability, inertial currents in the open sea and sea breeze-induced currents in the gulfs are present. Model-data comparison is performed in the CCS with altimeter data and satellite-derived turbidity distributions, and in the Gulf of Naples with the latter and with measurements performed with a high-frequency radar system. Significant model-data agreement is generally found.