Options
Ribotti, Alberto
Loading...
Preferred name
Ribotti, Alberto
3 results
Now showing 1 - 3 of 3
- PublicationOpen AccessNumerical simulation and decomposition of kinetic energy in the Central Mediterranean: insight on mesoscale circulation and energy conversion(2011)
; ; ; ; ; ;Sorgente, R. ;Olita, A. ;Oddo, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italia ;Fazioli, L. ;Ribotti, A. ; ;; ;The spatial and temporal variability of eddy and mean kinetic energy of the Central Mediterranean region has been investigated, from January 2008 to December 2010, by mean of a numerical simulation mainly to quantify the mesoscale dynamics and their relationships with physical forcing. In order to understand the energy redistribution processes, the baroclinic energy conversion has been analysed, suggesting hypotheses about the drivers of the mesoscale activity in this area. The ocean model used is based on the Princeton Ocean Model implemented at 1/32 horizontal resolution. Surface momentum and buoyancy fluxes are interactively computed by mean of standard bulk formulae using predicted model Sea Surface Temperature and atmospheric variables provided by the European Centre for Medium Range Weather Forecast operational analyses. At its lateral boundaries the model is one-way nested within the Mediterranean Forecasting System operational products. The model domain has been subdivided in four subregions: Sardinia channel and southern Tyrrhenian Sea, Sicily channel, eastern Tunisian shelf and Libyan Sea. Temporal evolution of eddy and mean kinetic energy has been analysed, on each of the four sub-regions, showing different behaviours. On annual scales and within the first 5m depth, the eddy kinetic energy represents approximately the 60% of the total kinetic energy over the whole domain, confirming the strong mesoscale nature of the surface current flows in this area. The analyses show that the model well reproduces the path and the temporal behaviour of the main known subbasin circulation features. New mesoscale structures have been also identified, from numerical results and direct observations, for the first time as the Pantelleria Vortex and the Medina Gyre276 232 - PublicationRestrictedThe Mediterranean Decision Support System for Marine Safety dedicated to oil slicks predictions(2016)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; ; ; ; ; ;; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;In the Mediterranean sea the risk from oil spill pollution is high due to the heavy traffic of merchantvessels for transporting oil and gas, especially after the recent enlargement of the Suez canal and to theincreasing coastal and offshore installations related to the oil industry in general. The basic response tomajor oil spills includes different measures and equipment. However, in order to strengthen the mar-itime safety related to oil spill pollution in the Mediterranean and to assist the response agencies, amulti-model oil spill prediction service has been set up, known as MEDESS-4MS (Mediterranean DecisionSupport System for Marine Safety). The concept behind the MEDESS-4MS service is the integration of theexisting national ocean forecasting systems in the region with the Copernicus Marine EnvironmentalMonitoring Service (CMEMS) and their interconnection, through a dedicated network data repository,facilitating access to all these data and to the data from the oil spill monitoring platforms, including thesatellite data ones, with the well established oil spill models in the region. The MEDESS-4MS offer arange of service scenarios, multi-model data access and interactive capabilities to suite the needs ofREMPEC (Regional Marine Pollution Emergency Response Centre for the Mediterranean Sea) and EMSA-CSN (European Maritime Safety Agency-CleanseaNet).103 2 - PublicationOpen AccessImpact of Freshwater Inflow From the Volturno River on Coastal Circulation(2020-06-03)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; The coastal area located in front of the Volturno river estuary (the Gulf of Gaeta, central-eastern Tyrrhenian Sea) was synoptically sampled in seven surveys between June 2012 and October 2014. Vertical profiles of temperature and salinity were acquired on a high-resolution nearly-regular grid in order to describe the spatial and temporal variability of the characteristics of the waters. Moreover, the three-dimensional velocity field associated with each survey was computed through the full momentum equations of the Princeton Ocean Model to provide a first assessment of the steady-state circulation at small scale. The data analysis shows the entire water column to be characterized by an evident thermal cycle and a vertical thermohaline structure, dominated by three types of waters: the freshwater of the river, the saltier coastal Tyrrhenian waters, and transitional waters originating from their mixing. The inflow of freshwater strongly affects the density distribution, leading to strong temporal variability in the upper layer. Its impact is more evident in winter, sometimes inducing a vertical temperature inversion. In case of rainy events, and also in conditions of high vertical temperature stratification, it forms a surface-trapped layer with high density gradients. These and wind forcing contribute to the formation of small-scale shallow features, such as longshore currents and cyclonic and anticyclonic eddies. The latter influence the vertical stratification and modify the coastal circulation, preserving the transitional waters from the surrounding saltier ones.233 23