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We describe the physical and dynamical characteristics of a mesoscale anticyclonic eddy observed in August 2013 over the shelf-break region of the northeastern sector of the Ligurian Sea, between the northeastern edge of the Northern Current (NC) and the coast. Results derive from a dense dataset of temperature, salinity and current measurements obtained from a multi-platform sampling strategy as well as from a diagnostic simulation with the Regional Ocean Modeling System (ROMS) at a horizontal resolution of 1.8 km. Model results are obtained from a strong nudging to observations and, as they are physically balanced, they allow a three-dimensional diagnosis of the dynamics and physical characteristics of the eddy. The eddy is centered around 9.5°E, 43.94°N, about 20 km from the coast, and has a radius of 16 km. It is characterized by low-density waters and penetrates the thermocline down to at least 300 m reflecting the main features of the NC. Horizontal velocities near the surface are around 0.4 m s, while at 150 m are still significantly high and close to 0.2 m s. Vertical velocities were estimated from model results; absolute values are below 4 m day until depths shallower than 150 m and increase with depth to 15 m day. The eddy's presence inverts the northwestwards flow traditionally portrayed in the region determining a southeastwards coastal circulation that replenishes coastal waters with those originating from the NC. We discuss several possible eddy formation mechanisms and suggest that its formation depends on the directionality of the NC when it enters the Ligurian Sea, as a result of the adjustment of the shear and orbital components of the current's relative vorticity.

During the Costa Concordia emergency case, regional, subregional, and relocatable ocean models have been used together with the oil spill model, MEDSLIK-II, to provide ocean currents forecasts, possible oil spill scenarios, and drifters trajectories simulations. The models results together with the evaluation of their performances are presented in this paper. In particular, we focused this work on the implementation of the Interactive Relocatable Nested Ocean Model (IRENOM), based on the Harvard Ocean Prediction System (HOPS), for the Costa Concordia emergency and on its validation using drifters released in the area of the accident. It is shown that thanks to the capability of improving easily and quickly its configuration, the IRENOM results are of greater accuracy than the results achieved using regional or subregional model products. The model topography, and to the initialization procedures, and the horizontal resolution are the key model settings to be configured. Furthermore, the IRENOM currents and the MEDSLIK-II simulated trajectories showed to be sensitive to the spatial resolution of the meteorological fields used, providing higher prediction skills with higher resolution wind forcing., Mediterranean Decision Support System for Marine Safety (MEDESS-4MS), TESSA Project, MyOcean2 Project

This paper represents a consensus on the state-of-the-art in wind retrieval using synthetic aperture radar (SAR), after the SEASAR 2012 workshop “Advances in SAR Oceanography” hosted by the European Space Agency (ESA) and the Norwegian Space Centre in Tromsø, Norway 18–22 June 2012. We document the recent advances of the methodologies, which are capitalizing on the improved capabilities of the modern generation of SAR sensors providing Doppler grid and multi-polarizations. The many applications of SAR wind retrieval have also benefitted from on the improved availability of wide swath modes (~500 km) with excellent coverage, giving much better overview of regional and mesoscale wind features. The accuracy of offshore wind retrieval is robust and generally in the order of 1.5 m/s in speed and 20° in direction, whereas the new methodologies steadily improve the performance for the more challenging conditions near cyclones and complex coastal topography.