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Since 2000, and for the following 20 years, hydrological data of the Mediterranean Sea, with a particular focus on the western and central Mediterranean sub-basins, have been acquired to study the hydrodynamics at both coastal and open sea scales. In total, 1468 hydrological casts were realized in 29 oceanographic cruises planned due to scientific purposes linked with funding research projects but were also sometimes driven by sea conditions and type of vessel. After accurate quality assurance and control, following standard procedures, all hydrological data were included in four online public open-access repositories in SEANOE (SEA scieNtific Open data Edition), available from https://doi.org/10.17882/87567 (Ribotti et al., 2022). Hydrological and dissolved oxygen data are always present in all of the datasets, whereas pH, fluorescence, turbidity, and chromophoric dissolved organic matter (CDOM) are available just for some cruises. Samplings were carried out mainly along transects, with some repetition over the years. The results of two data analyses, i.e., staircase systems in the Tyrrhenian Sea and in the Algero-Provençal sub-basin and spreading of the Western Mediterranean Transient, are mentioned.

Over a hundred of experiments were realised between 1998 and 2022 in the Mediterranean Sea using surface Lagrangian drifters, at coastal and offshore level. Raw data were initially unified and pre-processed manually by eliminating spikes and wrong positions or date/time information. The integrity of the received data packages was checked, and incomplete ones were discarded. Deployment information was retrieved from an initial excel database and campaign notes for each drifter and integrated into the PostgreSQL database, realised and maintained by the National Institute of Oceanography and Applied Geophysics (OGS) in Trieste (IT). This database also collects a variety of metadata about the drifter model, project, owner and operator. Subsequently data were processed using standard procedures of editing and quality control developed for the OGS Mediterranean drifter dataset to remove spikes generated by malfunctioning of the sensors and obtain files with common characteristics. Drifter data and plots of each track were also visually checked to remove any point not identified by the automatic procedure and clearly erroneous. Drifters’ trajectories were split into two or more segments that have been considered as different deployments, in case of specific drifters' behaviours. Data were interpolated at defined time intervals to temporarily unify tracks. From the original 138 experiments, a dataset of 204 tracks was obtained, available from the public open-access repository in SEANOE (SEA scieNtific Open data Edition) at https://doi.org/10.17882/90537 (Ribotti et al., 2022).

We designed a novel aggregated methodology to infer the impact of ocean motions on the movements of satellite-tracked marine turtles adopting available oceanographic observations and validated products of a numerical oceanographic forecasting system. The method was tested on an 11-months trajectory of a juvenile loggerhead turtle (LT) wandering in the Tyrrhenian Sea (Mediterranean Sea) that was reconstructed with a high-resolution GPS tracking system. The application of ad-hoc designed metrics revealed that the turtle’s route shape, ground speed and periodicities of its explained variance mimic the inertial motions of the sea, showing that this methodology is able to reveal important details on the relation between turtle movements and oceanographic features. Inertial motions were also identified in the observed trajectory of a surface drifting buoy sampling the Tyrrhenian Sea in a common period. At each sampling point of the turtle trajectory, the sea current eddy kinetic energy (EKE) and a Sea Current Impact index were computed from a validated set of high-resolution ocean modeling products and their analysis showed the relevant effects of the highly variable local sea currents mechanical action. Specifically, the metric we adopted revealed that the turtle trajectory was favorably impacted by the encountered sea current advection for about 70% of its length. The presented oceanographic techniques in conjunction with high-resolution tracking system provide a practicable approach to study marine turtle movements, leading the way to discover further insights on turtle behavior in the ocean.

This paper reviews the state of the art in storm surge forecasting and its particular application in the northern Adriatic Sea. The city of Venice already depends on operational storm surge forecasting systems to warn the population and economy of imminent flood threats, as well as help to protect the extensive cultural heritage. This will be more important in the future, with the new mobile barriers called MOSE (MOdulo Sperimentale Elettromeccanico, Experimental Electromechanical Module) that will be completed by 2021. The barriers will depend on accurate storm surge forecasting to control their operation. In this paper, the physics behind the flooding of Venice is discussed, and the state of the art of storm surge forecasting in Europe is reviewed. The challenges for the surge forecasting systems are analyzed, especially in view of uncertainty. This includes consideration of selected historic extreme events that were particularly difficult to forecast. Four potential improvements are identified: (1) improve meteorological forecasts, (2) develop ensemble forecasting, (3) assimilation of water level measurements and (4) develop a multimodel approach.

This contribution discusses an example of potential multi-hazard effects resulting from an earthquake in a highly seismogenic area of the Mediterranean Sea, the Augusta Bay, which presents high levels of contamination in sediments and seawater, due particularly to high-concentrations of mercury as a result of a long-term industrial exploitation. In particular, a high-resolution hydrodynamic and transport model is used to calculate the effects of enhanced mercury spreading in the open sea after significant damage and collapse of the artificial damming system confining the embayment where a very high concentration of Hg occurs in seafloor sediments and seawater. Coupling high-resolution 3D dynamic circulation modelling and sediment–seawater Hg fluxes calculated using the HR3DHG diffusion–reaction model for both inorganic and organic Hg species offers a valuable approach to simulating and estimating the effects of spatial dispersion of this contaminant due to unpredictable hazard events in coastal systems, with the potential attendant enhanced effects on the marine ecosystem. The simulated scenario definitely suggests that a combination of natural and anthropogenic multi-hazards calls for a thorough re-thinking of risk management in marine areas characterised by significant levels of contamination and where a deep understanding of the biogeochemical dynamics of pollutants does not cover all the aspects of danger for the environment.

Seagrass wrack are commonly found on the beach face of the sandy shore all around the world and often persists in situ during the whole year, favouring the emergence of conflicts for the use of the sandy coasts for bathing or for other recreational purposes. As a consequence, these deposits are often removed from the beach during the summer months, temporary stocked, and relocated on the shore face in the next autumn or winter season. The selection of the sites on the shoreline where the leaves should be released before the storms season is often an issue, considering the optimization needs between the transportation costs and the oceanographic features of the dumping site. In this study, a numerical approach was proposed to identify the most suitable areas for the autumnal repositioning of the seagrass wracks for two beaches of Sardinia, an island located in the Western Mediterranean Sea where Posidonia oceanica (L. Delile, 1813) is the most widespread seagrass species. The method is based on the use of hydrodynamic, wave, and particle tracking models and provides important indications useful for the management of this type of practice that can be extended to all different type of beaches along the Mediterranean coasts.

Several studies have shown the capabilities of Synthetic Aperture Radar to map sea currents in ocean regions mainly characterized by large flows. We consider the well known method based on the analysis of the Doppler Centroid. The Doppler, as, in general, the scattering from the sea, is sensitive to several phenomena, occurring between the upper ocean and atmospheric boundary layers. To investigate such phenomena, we considered the combined use of both ENVISAT calibrated amplitude and Doppler data in conjunction with hindcast wind information provided by atmospheric models as well as Wind and Doppler Geophysical Model Functions (W/D-GMF) developed, in the literature, for C-Band systems. This integrated analysis for the interpretation of the Doppler surface currents measurements was carried out on a case study located in the Mediterranean Sea which is characterized by a general low circulation regime: specifically, the coastal region around the city of Naples. In this case study, we show that generally, wind plays a direct significant role in the observed Doppler surface current. The availability of an oceanographic numerical model for one of the analyzed cases also allowed us to attempt to interpret the effect of the typical thermohaline circulation pattern on the Doppler anomaly.

Useful information, such as water levels, currents, salinity and temperature dynamics in water bodies, are obtained through numerical models in order to pursue scientific research or consultancy. Model validation dates back long ago, since such models started to be developed in the 1960s. Despite their usefulness and reliability in complex situations, some issues related to well-known benchmarks are still present. This work aims to analyse in detail the behaviour of the velocity profile, vertical eddy viscosity and tangential stresses at the bed in two cases of free surface flows, namely: uniform flow in an inclined rectangular channel and a wind-induced circulation in a closed basin. Computational results strongly depend on the turbulence closure model employed and a reasoned comparison is necessary to highlight possible improvements of these models. The strong differences that arise are deeply analysed in this work.

The global decline of canopy-forming macroalgae has stimulated research on the mechanism regulating shifts among alternative habitats on rocky reefs. The effects of sea urchin grazing and alterations of environmental conditions are now acknowledged as the main drivers of shifts between canopy-formers and encrusting coralline barrens and algal turfs, respectively. The conditions under which these mechanisms operate remains, however, somewhat elusive. This is mostly a consequence of the fact that our current understanding has been generated by envisioning habitat shifts as dichotomic, at odds with rocky reef landscapes being composed by mosaics of habitats and with evidence of strong interactions among the species that compose each of the alternative habitats. Using data from a long-term sampling program and path analysis, we investigated how wave-exposure and human-induced degradation of environmental conditions regulate the mechanisms maintaining algal canopies formed by Cystoseira crinita, barren habitats and algal turfs as alternative states on subtidal reefs in the NW Mediterranean. In the Tuscan Archipelago, wave-exposure had positive effects on sea urchins, which, likely due to their low mean density, had weak effects on each of the alternative habitats. Canopy-forming macroalgae resulted, instead, to exert strong negative effects on the abundance of algal turfs. Since data from the Tuscan Archipelago did not explain any of the variation in the abundance of C. crinita canopies, a further analysis was performed including data from the coast of Tuscany to assess the role of cumulative human impacts in regulating habitat shifts. This showed that degradation of environmental conditions is a direct cause of the decline of macroalgal canopies, indirectly favouring the dominance of algal turfs. Our study suggests that management of human impacts should be considered a priority for preserving subtidal canopies formed by Cystoseira in the NW Mediterranean and that conservation efforts based exclusively on the control of sea urchin populations might be doomed to failure in some areas.

Reliable and timely information on the environmental conditions at sea is key to the safety of professional and recreational users as well as to the optimal execution of their activities. The possibility of users obtaining environmental information in due time and with adequate accuracy in the marine and coastal environment is defined as sea situational awareness (SSA). Without adequate information on the environmental meteorological and oceanographic conditions, users have a limited capacity to respond, which has led to loss of lives and to large environmental disasters with enormous consequent damage to the economy, society and ecosystems. Within the framework of the TESSA project, new SSA services for the Mediterranean Sea have been developed. In this paper we present SeaConditions, which is a web and mobile application for the provision of meteorological and oceanographic observation and forecasting products. Model forecasts and satellite products from operational services, such as ECMWF and CMEMS, can be visualized in SeaConditions. In addition, layers of information related to bathymetry, sea level and ocean-colour data (chl a and water transparency) are displayed. Ocean forecasts at high spatial resolutions are included in the version of SeaConditions presented here. SeaConditions provides a user-friendly experience with a fluid zoom capability, facilitating the appropriate display of data with different levels of detail. SeaConditions is a single point of access to interactive maps from different geophysical fields, providing high-quality information based on advanced oceanographic models. The SeaConditions services are available through both web and mobile applications. The web application is available at www.sea-conditions.com and is accessible and compatible with present-day browsers. Interoperability with GIS software is implemented. User feedback has been collected and taken into account in order to improve the service. The SeaConditions iOS and Android apps have been downloaded by more than 105000 users to date (May 2016), and more than 100000 users have visited the web version.

In the Strait of Sicily (SoS), a wide passage of the Mediterranean Sea, Parapenaeus longirostris, (Lucas, 1846; DPS hereafter) is the main target species of trawl fisheries, with an estimated annual market value of about 80 million euro. The exploitation of this resource is shared between Italian, Tunisian and Maltese bottom trawlers and its management raises social, economic and environmental interests. Recent stock assessment revealed high fishing mortalities and low size at first capture, thus promoting the adoption of a strategic plan for a sustainable management. However, the current knowledge of the geographical boundaries of the stock, supporting the implementation of such management plan is still poor. In this respect, under different hydrodynamic regimes, particle-tracking modelling was used to explore connectivity between both, known and unexplored, spawning and nursery areas of DPS in the SoS. Ensembles scenarios derived by model outcomes displayed decadal changes in connectivity between spawning and nursery areas in the north side of the SoS, hence confirming the presence of a single stock in this area. Expanding the area of investigation, the model results showed weak connectivity between spawning ground in the north side of SoS and nurseries on the African shelf-break. This method could support the spatial management of the stock, such as the protection of the nursery and spawning areas, by providing estimates of how connectivity is influenced by hydrodynamic regimes at different temporal and spatial scales.

The biogeochemical dynamics of Hg, and specifically of its three species Hg0, HgII, and MeHg (elemental, inorganic, and organic, respectively) in the marine coastal area of Augusta Bay (southern Italy) have been explored by the high resolution 3D Hg (HR3DHG) model, namely an advection-diffusion-reaction model for the dissolved mercury in the seawater compartment coupled with i) a diffusion-reaction model for dissolved mercury in the pore water of sediments and ii) a sorption/de-sorption model for total mercury in the sediments. The spatio-temporal variability of dissolved and total mercury concentration both in seawater ([HgD] and [HgT]) first layers of bottom sediments ([HgsedD] and [HgsedT]), and the Hg fluxes at the boundaries of the 3D model domain have been theoretically reproduced, showing an excellent agreement with the experimental data, collected in multiple field observations during six different oceanographic cruises. The mass-balance of the different Hg species in seawater has been calculated for the Augusta Harbor, improving previous estimations. The HR3DHG model includes modules that can be implemented for specific and detailed exploration of the effects of climate change on the spatio-temporal distribution of Hg in highly contaminated coastal-marine areas.

In the last decades, the Mediterranean Sea experienced an increasing trend of fish stocks in overfishing status. Therefore, management actions to achieve a more sustainable exploitation of fishery resources are required and compelling. In this study, a spatially explicit multi-species bio-economic modeling approach, namely, SMART, was applied to the case study of central Mediterranean Sea to assess the potential effects of different trawl fisheries management scenarios on the demersal resources. The approach combines multiple modeling components, integrating the best available sets of spatial data about catches and stocks, fishing footprint from vessel monitoring systems (VMS) and economic parameters in order to describe the relationships between fishing effort pattern and impacts on resources and socio-economic consequences. Moreover, SMART takes into account the bi-directional connectivity between spawning and nurseries areas of target species, embedding the outcomes of a larvae transport Lagrangian model and of an empirical model of fish migration. Finally, population dynamics and trophic relationships are considered using a MICE (Models of Intermediate Complexity) approach. SMART simulates the fishing effort reallocation resulting from the introduction of different management scenarios. Specifically, SMART was applied to evaluate the potential benefits of different management approaches of the trawl fisheries targeting demersal stocks (deepwater rose shrimp Parapenaeus longirostris, the giant red shrimp Aristaeomorpha foliacea, the European hake Merluccius merluccius, and the red mullet Mullus barbatus) in the Strait of Sicily. The simulated management scenarios included a reduction of both fishing capacity and effort, two different sets of temporal fishing closures, and two sets of spatial fishing closures, defined involving fishers. Results showed that both temporal and spatial closures are expected to determine a significant improvement in the exploitation pattern for all the species, ultimately leading to the substantial recovery of spawning stock biomass for the stocks. Overall, one of the management scenarios suggested by fishers scored better and confirms the usefulness of participatory approaches, suggesting the need for more public consultation when dealing with resource management at sea.

Striped seagrass meadows are formed by narrow ribbons which are elevated over the seabed and separated by channels. Limited information on the genesis and development of this morphological pattern, including the adaptive responses of associated biota, is preventing holistic insight into the functioning of such protected ecosystems. This paper assessed the structural dynamics of a Posidonia oceanica striped meadow and the distribution and 3D orientation of the associated bivalve Pinna nobilis. Our analysis of the interaction between bedforms, bottom currents, and the distribution of P. nobilis revealed that the striped seascape is the result of a self-organisation process driven by feedback interactions among seagrass growth, sediment deposition, and hydrodynamics. The results suggest that the ribbon wall is the most suitable sub-habitat for this species, because it supports the highest density of P. nobilis, compared to the meadow top and bottom. Here, specimens can take advantage of the resuspension induced by hydrodynamics and open their shells towards the current, thus enhancing food intake. Therefore, our results show that self-organisation in striped seagrass meadow affects the distributional pattern of P. nobilis, providing new insights into the autoecology of this species beyond the conservation implications for its habitat.

A forecasting and hazard assessment system for oil dispersion from Italian oil rigs was set up within the framework of a national research project. The system is based on 3D hydrodynamic, mesoscale resolving models providing forcing fields for a Lagrangian module of oil dispersion and slick evolution (oil transport and transformation). The tool provides,daily, the outputs of numerical simulations of possible oil spills from extraction platform sites. In this work we present the results for the 3 platforms closest to the Italian coast. Aside the operational usage, the numerical outputs are also stored and adopted to compute statistics of the slick distributions in the coastal and marine areas of interest. The hazard was assessed by means of two different indices (Hazard Index and Occurrence Index) based on the operational system outputs, for the estimation of the hazard at sea (marine hazard or aerial hazard). As short forecasts (2 days long) often do not allow the oil to reach the coast, an extra set of long-period simulations has been performed in order to compute a third Hazard Index (Coastal Hazard Index) suitable to estimate the hazard along the shorelines.\\ The adopted methodology allowed, as a whole, to assess both coastal and marine oil spill hazard due to oil spill extraction activities. The indices constitute a basic informative layer on which the environmental risk could be also evaluated, once opportunely combined with coastal vulnerability and sensitivity layers.

Quattrocchi, A.; Gorman, J.G., Piggott M.D. and Cucco, A., 2016. M2, overtides and compound tides generation in the Strait of Messina: the response of a non-hydrostatic, finite-element ocean model. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 657–661. Coconut Creek (Florida), ISSN 0749-0208. The nonlinear interactions between the main tidal constituents and geographical constraints are investigated using Fluidity-ICOM, a non-hydrostatic finite-element ocean model that was implemented in the region of the Strait of Messina (Mediterranean Sea). As a first crucial approach, the barotropic tidal dynamics was investigated and the model solution was interpreted in terms of tidal maps and spectra obtained by harmonic analysis of the sea surface elevation. The model domain is represented by an unstructured mesh with variable spatial resolution...

An operational ocean forecasting system provided numerical predictions on the main hydrodynamics in the seas around Sicily. The system is evaluated using an independent dataset of sea surface tempe...

Sea urchins act as a keystone herbivore in marine coastal ecosystems, regulating macrophyte density, which offers refuge for multiple species. In the Mediterranean Sea, both the sea urchin Paracentrotus lividus and fish preying on it are highly valuable target species for artisanal fisheries. As a consequence of the interactions between fish, sea urchins and macrophyte, fishing leads to trophic disorders with detrimental consequences for biodiversity and fisheries. In Sardinia (Western Mediterranean Sea), regulations for sea urchin harvesting have been in place since the mid 90s. However, given the important ecological role of P. lividus, the single-species fishery management may fail to take into account important ecosystem interactions. Hence, a deeper understanding of population dynamics, their dependance on environmental constraints and multispecies interactions may help to achieve long-term sustainable use of this resource. This work aims to highlight how sea urchin population structure varies spatially in relation to local environmental constraints and species interactions, with implications for their management. The study area (Sinis Peninsula, West Sardinia, Italy) that includes a Marine Reserve was divided into five sectors. These display combinations of the environmental constraints influencing sea urchin population dynamics, namely type of habitat (calcareous rock, granite, basalt, patchy and continuous meadows of Posidonia oceanica), average bottom current speed and predatory fish abundance. Size-frequency distribution of sea urchins under commercial size (P. oceanica meadows. The density of middle-sized sea urchins was more abundant in calcareous rock than in basalt, granite or P. oceanica. High densities of recruits resulted significantly correlated to low values of average bottom current speed, while a negative trend between the abundance of middle-sized sea urchins and predatory fish was found. Our results point out the need to account for the environmental constraints influencing local sea urchin density in fisheries management.

An innovative forecasting system of the coastal marine circulation has been implemented in the Bonifacio Strait area, between Corsica and Sardinia, using a numerical approach to facilitate the rapid planning and coordination of remedial actions for oil spill emergencies at sea by local authorities. Downscaling and nesting techniques from regional to coastal scale and a 3-D hydrodynamic numerical model, coupled with a wind wave model, are the core of the integrated Bonifacio Strait system. Such a system is capable of predicting operationally the dispersion of hydrocarbon spills in the area, both in forward and backward mode, through an easy-to-use graphical user interface. A set of applications are described and discussed including both operational applications aimed at providing rapid responses to local oil spill emergences and managing applications aimed at mitigating the risk of oil spill impacts on the coast.

The research leading to these results has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration (FP7/2007-2013) within the Ocean of Tomorrow call under Grant Agreement No.266445 for the project Vectors of Change in Oceans and Seas Marine Life, Impact on Economic Sectors (VECTORS). This work is also a contribution to the EU Cost Action FA1004 "Conservation Physiology". PS acknowledges support from the UK Natural Environment Research Council and Department for Environment, Food and Rural Affairs [grant number NE/L003279/1, Marine Ecosystems Research Programme. The authors wish to thank Drs. Jason Link, Elizabeth Fulton and Oivind Fiksen as well as an anonymous reviewer for their helpful comments on an earlier version of this manuscript. This work also benefitted from discussions among members of the ICES Working Group on Integrated Physical biological and Ecosystem Modelling (WGIPEM) and the ICES-PICES Strategic Initiative on Climate Change Impacts on Marine Ecosystems (SICCME). Academic press ltd- elsevier science ltd London Si Marine & Freshwater Biology; Oceanography Iences, v367, p2979 Iences, v367, p1607; International audience; We review and compare four broad categories of spatially-explicit modelling approaches currently used to understand and project changes in the distribution and productivity of living marine resources including: 1) statistical species distribution models, 2) physiology-based, biophysical models of single life stages or the whole life cycle of species, 3) food web models, and 4) end-to-end models. Single pressures are rare and, in the future, models must be able to examine multiple factors affecting living marine resources such as interactions between: i) climate-driven changes in temperature regimes and acidification, ii) reductions in water quality due to eutrophication, iii) the introduction of alien invasive species, and/or iv) (over-)exploitation by fisheries. Statistical (correlative) approaches can be used to detect historical patterns which may not be relevant in the future. Advancing predictive capacity of changes in distribution and productivity of living marine resources requires explicit modelling of biological and physical mechanisms. New formulations are needed which (depending on the question) will need to strive for more realism in ecophysiology and behaviour of individuals, life history strategies of species, as well as trophodynamic interactions occurring at different spatial scales. Coupling existing models (e.g. physical, biological, economic) is one avenue that has proven successful. However, fundamental advancements are needed to address key issues such as the adaptive capacity of species/groups and ecosystems. The continued development of end-to-end models (e.g., physics to fish to human sectors) will be critical if we hope to assess how multiple pressures may interact to cause changes in living marine resources including the ecological and economic costs and trade-offs of different spatial management strategies. Given the strengths and weaknesses of the various types of models reviewed here, confidence in projections of changes in the distribution and productivity of living marine resources will be increased by assessing model structural uncertainty through biological ensemble modelling.

Aldehyde oxidase (AOX) is a metabolic enzyme catalyzing the oxidation of aldehyde and aza-aromatic compounds and the hydrolysis of amides, moieties frequently shared by the majority of drugs. Despite its key role in human metabolism, to date only fragmentary information about the chemical features responsible for AOX susceptibility are reported and only "very local" structure-metabolism relationships based on a small number of similar compounds have been developed. This study reports a more comprehensive coverage of the chemical space of structures with a high risk of AOX phase I metabolism in humans. More than 270 compounds were studied to identify the site of metabolism and the metabolite(s). Both electronic [supported by density functional theory (DFT) calculations] and exposure effects were considered when rationalizing the structure-metabolism relationship.

Mediterranean beaches experience major modifications in their morphology and grain size features mainly during intense storms and extreme meteo-marine events. The assessment of beach response to storms can be useful in the evaluation of coastal hazards, and in relation to the efficiency of management projects such as artificial nourishment. This paper aims to establish the subaerial morphological response of a beach located in western Sardinia (western Mediterranean) during the period of a year. Both experimental and numerical approaches were adopted to investigate the beach system. In particular, beach profiles, acquired by means of Differential Positioning System were used to analyze the morphological changes of the beach and wave parameters and current velocity data were collected by means of an Acoustic wave and current meter (ADCP). Numerical techniques were also applied to investigate the hydrodynamics in the area of study. Coupled wind wave - 3D hydrodynamic finite element model were used to reproduce the wave propagation and the wind, tide and wave induced 3D water circulation along the coastal areas, and it displayed a good accuracy. During the year, the beach experienced intense morphological changes in the area where submerged beach is not occupied by rocky outcrops and the model was also able to reproduce the related observed periods of strong wind wave events. The interdisciplinary approach allowed an evaluation to be made about the response of the beach morphology in respect to meteo-marine forcings.

Oil extraction platforms are potential sources of oil spills. For this reason, an oil spill forecasting system was set up to support the management of emergencies from the oil fields in the Italian seas. The system provides ready-to-use products to the relevant response agencies and optimizes the anti-pollution resources by assessing hazards and risks related to this issue. The forecasting system covers seven working oil platforms in the Sicily Channel and middle/low Adriatic Sea. It is composed of a numerical chain involving nested ocean models from regional to coastal spatial scales and an oil spill model. The system provides two online services, one automatic and a second dedicated to possible real emergencies or exercises on risk preparedness and responding. The automatic service produces daily short-term simulations of hypothetical oil spill dispersion, transport, and weathering processes from each extraction platform. Products, i.e., risk maps, animations, and a properly called bulletin, are available on a dedicated web-portal. The hazard estimations are computed by performing geo-statistical analysis on the daily forecasts database. The second service is activated in near-real-time producing oil spill simulations for the following 48 h.

Pinna nobilis is the largest endemic bivalve of the Mediterranean Sea, declared protected since 1992. Although hydrodynamic stress induced by waves is known to influence density, size and orientation of P. nobilis , the effect of other hydrological features is unknown. This paper considers a P. nobilis population living within a Posidonia oceanica meadow in the Gulf of Oristano (Sardinia, Italy). We hypothesize that spatial differences in density and orientation of P. nobilis may be related to significant wave height (H S ), wave direction (D W ), bottom current direction (D BC ) and bottom current speed (S BC ). A population of P. nobilis was investigated at different sites and its distribution was correlated to hydrodynamics by means of a numerical modeling approach. The spatial distribution was patchy, with a density of 0.06–6.7 ind. 100 m − 2 . A non-uniform distribution of shell orientations (O S ) was demonstrated in 4 sites out of 6. D BC and S BC were the main factors affecting O S , while waves had little influence. A S BC of 0.07 m s − 1 appears to be the threshold for inducing specimen directionality with shells aligned to the current and the ventral side exposed to the flow. This suggests that feeding strategy is a key factor in determining O S , in addition to drag minimization. We also highlighted the role of adjacent lagoons in supporting high densities as a result of high food availability. These findings demonstrate the usefulness of modeling techniques in explaining the spatial distribution pattern of P. nobilis and in contributing to our knowledge of its ecological traits.

This work explores the importance of considering tidal dynamics when modelling the general circulation in the Messina Strait, a narrow passage connecting the Tyrrhenian and the Ionian subbasins in the Western Mediterranean Sea. The tides and the induced water circulation in this Strait are among the most intense oceanographic processes in the Mediterranean Sea. The quantification of these effects can be particularly relevant for operational oceanographic systems aimed to provide short-term predictions of the main hydrodynamics in the Western Mediterranean subbasins. A numerical approach based on the use of a high-resolution hydrodynamic model was followed to reproduce the tides propagation and the wind-induced and thermohaline water circulation within the Strait and in surrounding areas. A set of numerical simulations was carried out to quantify the role of the Strait dynamics on the larger-scale water circulation. The obtained results confirmed the importance of a correct representation of the hydrodynamics in the Messina Strait even when focusing on predicting the water circulation in the external sea traits. In fact, model results show that tidal dynamics deeply impact the reproduction of the instantaneous and residual circulation pattern, waters thermohaline properties and transport dynamics both inside the Messina Strait and in the surrounding coastal and open waters.

Wave climate, sediments, topographic features and tides influence the morphology and the short-term dynamics of beaches. The interactions between these different forcings affect the features of the beach system. In this work the morphological beach responses in relation to the most energetic period of the year were studied in a coastline with high geomorphological complexity. Three beaches, located along the Sinis Peninsula (western Mediterranean Sea, western Sardinia), were monitored for about 6 months. In order to estimate morphological changes, repetitive beach profiles were acquired by means of Differential Global Positioning System. Wave data were collected by an offshore wave buoy and the grainsize features of each beach was determined. A coupled 3D hydrodynamics- wave, finite element model was also applied in order to investigate the current dynamics and the wave propagation along the selected coastal area. During the monitoring period, the beaches experienced relevant changes when consecutive storms occurred. In sediment deprived embayed beaches, the presence of headlands interacting with waves, favored beach rotation and lead to a crenulate shape of the shoreline. In addition, on sediment abundant beach, cross-shore sediment transport and simultaneous shoreline retreats were observed during storms events. Finally, the effects on the wave heights and directions, due complex coastline features of the Sinis Peninsula, were discussed in relation to the morphodynamics response of each beach.

This work deals with the spatial characteristics of the wind fields evaluated from synthetic aperture radar (SAR) images and simulated by the weather research and forecasting (WRF) atmospheric model in the Gulf of Oristano, a small coastal area about $10\;\text{km} \times 18\;\text{km}$ wide in western coast of Sardinia (Western Mediterranean Sea). The SAR-derived wind fields have been obtained analyzing images of the COSMO-SkyMed, Radarsat-2, and Sentinel-1A satellites through a fully two-dimensional continuous wavelet transform (2-D-CWT) method. The analysis of the wind directions has shown that the model variability is limited if compared to that inferred by 2-D-CWT method, which mostly respects the variability evidenced by in situ data. As the use of model directions to compute the SAR wind fields is a standard in many studies, the impact on the SAR wind speed retrieval of using the model instead of the SAR-derived directions has been assessed: differences of wind speed greater than $\pm$ 10% occur for about the 20% of data. The spatial variability of the SAR and model wind speed fields results quite different at both local and domain scales. The knowledge of the spatial variations of the surface wind fields can be very important for the oceanographic applications and constitutes the added value brought by SAR in the description of the coastal wind. For this reason, the SAR-derived wind fields should be taken as reference in many kind of applications.

This work deals with the spatial characteristics of the wind fields evaluated from synthetic aperture radar (SAR) images and simulated by the weather research and forecasting (WRF) atmospheric model in the Gulf of Oristano, a small coastal area about 10 km × 18 km wide in western coast of Sardinia (Western Mediterranean Sea). The SAR11 derived wind fields have been obtained analyzing images of the COSMO-SkyMed, Radarsat-2, and Sentinel-1A satellites through a fully two-dimensional continuous wavelet transform (2-D-CWT) method. The analysis of the wind directions has shown that the model variability is limited if compared to that inferred by 2-D-CWT method, which mostly respects the variability evidenced by in situ data. As the use of model directions to compute the SAR wind fields is a standard in many studies, the impact on the SAR wind speed retrieval of using the model instead of the SAR20 derived directions has been assessed: differences of wind speed greater than ±10% occur for about the 20% of data. The spatial variability of the SAR and model wind speed fields results quite different at both local and domain scales. The knowledge of the spatial variations of the surface wind fields can be very important for the oceanographic applications and constitutes the added value brought by SAR in the description of the coastal wind. For this rea27 son, the SAR-derived wind fields should be taken as reference in many kind of applications.

At the end of May, 17 scientists involved in an EU COST Action on Conservation Physiology of Marine Fishes met in Oristano, Sardinia, to discuss how physiology can be better used in modelling tools to aid in management of marine ecosystems. Current modelling approaches incorporate physiology to different extents, ranging from no explicit consideration to detailed physiological mechanisms, and across scales from a single fish to global fishery resources. Biologists from different sub-disciplines are collaborating to rise to the challenge of projecting future changes in distribution and productivity, assessing risks for local populations, or predicting and mitigating the spread of invasive species.

Eco-physiology studies, performed in laboratory under controlled conditions, provide an essential tool for quantifying the impact of environmental changes on the metabolism and behaviour of individual fish. One way of quantifying such impact is by measuring the Metabolic Scope (MS) of a fish and how it is affected by environmental factors. Laboratory experiments were performed to calculate the empirical mathematical equations describing the variation of the MS of flathead grey mullet, Mugil cephalus , under different environmental conditions (water temperature and water oxygen concentration). The equation obtained was introduced into a coupled hydrodynamic–ecological numerical model able to reproduce the variability of the water temperature, salinity, dissolved oxygen, and of the main dissolved nutrients and chlorophyll- a . The coupled empirical–numerical model was used to reproduce the temporal and spatial variation in MS of a M. cephalus fish population in the Oristano gulf and the Cabras lagoon system (Italy), a typical Mediterranean shallow water environment. Results from numerical simulations show that during the spring and the beginning of summer period, Cabras lagoon provides a higher MS for M. cephalus than the Oristano gulf. During the rest of the year, apart from some transitional phases, the gulf provides more suitable conditions (higher MS) for M. cephalus . The obtained results are in general accordance with fisheries data, showing that M. cephalus catches are highest during the end-July to August period, as they migrate out of the lagoon. This approach, combined with observation on the temporal and spatial distribution of fishes, can allow predictions of fish productivity in non-limiting conditions.

The fan mussel Pinna nobilis is the largest bivalve of the Mediterranean Sea, declared protected since 1992. It is a sessile suspension feeder endemic of this basin which lives mainly on soft sediments colonized by seagrass meadows. This study considers a population living within a Posidonia oceanica bed in the Gulf of Oristano (W Sardinia, Italy), a site included within a Marine Protected Area and in two Sites of Community Importance. Based on field surveys conducted in 2007, 2009 and 2014 differences in density, size, and shell burial level of P. nobilis were investigated in relation to meadow's distribution and characteristics. Moreover, the spatial differences in density and orientation of P. nobilis were related to hydrological features. P. nobilis showed a mean density of 4.06±1.13 ind./100 m2 and a significant increase in population size was observed between 2009 and 2014. A high-resolution multibeam survey revealed that the P. oceanica bed was characterized by a striped structure. Toward the inner sheltered sector of Gulf, the meadow became hill-shaped. A comparison between meadow structure and P. nobilis distribution showed that specimens are mainly located at the edge of the channels within the striped meadow, whereas the edge effect resulted less noticeable within the hill-shaped meadow. The compactness of the seabed influences the shell stability: the burial level decreased with the increasing of fine sediments. Bottom current direction and speed are the main factors influencing shell orientation, whereas wave action is negligible. Where bottom current speed exceeded 0.07 m/s specimens resulted in line with the prevalent current direction with the ventral side exposed to incoming flow. These features suggest that feeding strategy is an important factor in determining shell orientation, possibly in addition to drag. Food availability could be the driving force in determining the patchiness distribution of P. nobilis population with higher values in those sites close to the mouth of the lagoons, in sedimentation area or in the meadow channels where the water flow is conveyed. These findings contribute to increase the knowledge on the P. nobilis-P. oceanica association and provide useful information for improving conservation measures.

Global increase in sea temperatures has been suggested to facilitate the incoming and spread of tropical invaders. Here, we determined the effect of temperature on the aerobic metabolic scope of two competing fish species, one native and one invasive, and we predicted their future thermal habitat suitability., Global increase in sea temperatures has been suggested to facilitate the incoming and spread of tropical invaders. The increasing success of these species may be related to their higher physiological performance compared with indigenous ones. Here, we determined the effect of temperature on the aerobic metabolic scope (MS) of two herbivorous fish species that occupy a similar ecological niche in the Mediterranean Sea: the native salema (Sarpa salpa) and the invasive marbled spinefoot (Siganus rivulatus). Our results demonstrate a large difference in the optimal temperature for aerobic scope between the salema (21.8°C) and the marbled spinefoot (29.1°C), highlighting the importance of temperature in determining the energy availability and, potentially, the distribution patterns of the two species. A modelling approach based on a present-day projection and a future scenario for oceanographic conditions was used to make predictions about the thermal habitat suitability (THS, an index based on the relationship between MS and temperature) of the two species, both at the basin level (the whole Mediterranean Sea) and at the regional level (the Sicilian Channel, a key area for the inflow of invasive species from the Eastern to the Western Mediterranean Sea). For the present-day projection, our basin-scale model shows higher THS of the marbled spinefoot than the salema in the Eastern compared with the Western Mediterranean Sea. However, by 2050, the THS of the marbled spinefoot is predicted to increase throughout the whole Mediterranean Sea, causing its westward expansion. Nevertheless, the regional-scale model suggests that the future thermal conditions of Western Sicily will remain relatively unsuitable for the invasive species and could act as a barrier for its spread westward. We suggest that metabolic scope can be used as a tool to evaluate the potential invasiveness of alien species and the resilience to global warming of native species.

A comparison study between 10 Mediterranean lagoons has been carried out by means of the 3-D numerical model SHYFEM. The investigated basins are the Venice and Marano-Grado lagoons in the Northern Adriatic Sea, the Lesina and Varano lagoons in the Southern Adriatic Sea, the Taranto basin in the Ionian Sea, the Cabras Lagoon in Sardinia, the Ganzirri and Faro lagoons in Sicily, the Mar Menor in Spain, and the Nador Lagoon in Morocco. This study has been focused on hydrodynamics in terms of exchange rates, transport time scale, and mixing. Water exchange depends mainly on the inlet shape and tidal range, but also on the wind regimes in the case of multi-inlet lagoons. Water renewal time, which is mostly determined by the exchange rate, is a powerful concept that allows lagoons to be characterized with a time scale. In the case of the studied lagoons, the renewal time ranged from few days in the Marano-Grado Lagoon up to 1 year in the case of the Mar Menor. The analysis of the renewal time frequency distribution allows identifying subbasins. The numerical study proved to be a useful tool for the intercomparison and classification of the lagoons. These environments range from a leaky type to a choked type of lagoons and give a representative picture of the lagoons situated around the Mediterranean basin. Mixing efficiency turns out to be a function of the morphological complexity, but also of the forcings acting on the system. Key Points Comparative study of 10 Mediterranean lagoons using a 3-D hydrodynamic model Characterization of flushing, mixing efficiency, and water renewal Classification of lagoons based on water renewal time and exchange rate © 2014. American Geophysical Union. All Rights Reserved.

An innovative forecasting system of the coastal marine circulation has been implemented in the Bonifacio Strait area, between Corsica and Sardinia, using a numerical approach to facilitate the rapid planning and coordination of remedial actions to oil spill emergencies at sea by local authorities. Downscaling and nesting techniques from regional to coastal scale and a 3-D hydrodynamic numerical model, coupled with a wind wave model, are the core of the integrated Bonifacio Strait system. Such a system is capable to predict the sea state and the dispersion of hydrocarbon spills in the area, providing the forecasts on oil spills through an easy-to-use graphical user interface. Scenarios and risk maps have been created to identify the most risky areas to oil pollution in relation to vessels traffic. The backward investigation technique has been exploited to trace the most probable area from which pollution was generated. The system has been operationally verified in January 2011 when an oil spill occurred in the area. Finally output data are daily released providing forecasting services to end-users through the web.

The impact of the assimilation of MyOcean sea level anomalies along-track data on the analyses of the Sicily Channel Regional Model was studied. The numerical model has a resolution of 1/32° degrees and is capable to reproduce mesoscale and sub-mesoscale features. The impact of the SLA assimilation is studied by comparing a simulation (SIM, which does not assimilate data) with an analysis (AN) assimilating SLA along-track multi-mission data produced in the framework of MyOcean project. The quality of the analysis was evaluated by computing RMSE of the misfits between analysis background and observations (sea level) before assimilation. A qualitative evaluation of the ability of the analyses to reproduce mesoscale structures is accomplished by comparing model results with ocean colour and SST satellite data, able to detect such features on the ocean surface. CTD profiles allowed to evaluate the impact of the SLA assimilation along the water column. We found a significant improvement for AN solution in terms of SLA RMSE with respect to SIM (the averaged RMSE of AN SLA misfits over 2 years is about 0.5 cm smaller than SIM). Comparison with CTD data shows a questionable improvement produced by the assimilation process in terms of vertical features: AN is better in temperature while for salinity it gets worse than SIM at the surface. This suggests that a better a-priori description of the vertical error covariances would be desirable. The qualitative comparison of simulation and analyses with synoptic satellite independent data proves that SLA assimilation allows to correctly reproduce some dynamical features (above all the circulation in the Ionian portion of the domain) and mesoscale structures otherwise misplaced or neglected by SIM. Such mesoscale changes also infer that the eddy momentum fluxes (i.e. Reynolds stresses) show major changes in the Ionian area. Changes in Reynolds stresses reflect a different pumping of eastward momentum from the eddy to the mean flow, in turn influencing transports through the channel.

A comparison was made of shallow water sediments from the Lagoon of Venice (LV) and the Lagoon of Cabras (LC), comparing depositional environments and exploring the relationships between hydrodynamics and sedimentological parameters. The two water bodies are very different in size (LV: 360 km2; LC: 22 km2), and the sediments predominantly consist of silty-clay (LV: Mz¿26 µm; LC: Mz¿6 µm). However, there are large differences between the two lagoons with respect to sand (LV: mean 19%; LC: mean ~3%) and clay (LV: mean 20%; LC: mean 45%) contents. The Lagoon of Venice (mean depth ~1 m) can be considered a tidal basin, whereas the Lagoon of Cabras (mean depth ~2 m) has the character of a coastal lake in which wind is the main hydrodynamic forcing factor. A comparison of sediment grain-size distributions with water circulation patterns in different parts of the lagoons highlighted some interesting differences. Grain-size analyses of samples reveal a deficiency of particles around 8 µm in the LC, which is interpreted as reflecting the transition between cohesive flocs/aggregates and non-cohesive coarser silt particles, while the transition limit in the LV is ~20 µm. Thus, particles are cohesive below 8 µm in the LC and below ~20 µm in the LV. This is probably because of the differences in the clay/silt ratio, which is much lower in the LV (~0.3) than in LC (~1), conferring a ¿silt-dominated network structure¿ on most of the LV sediments. The hydrographical data used were root mean square velocity (RMSV) and water residence time (WRT), computed under the main forcing conditions. The results show a general correlation between RMSV and sortable silt in the LC, and between RMSV and coarser sediments (63¿105 µm) in the LV. Some significant differences between the lagoons were detected in the degree of correlation between WRTand grain size. Root mean square velocity (~7 cm s-1 in the LV and ~3 cm s-1 in the LC) was a greater forcing factor in the LC than in the LV. Conversely, WRT, which is on average ~16 days in the LV and ~19 days in the LC, has more influence in the LV. This study highlights the usefulness of comparing environments with different hydrodynamic energies, e.g., tidal and/or wind-driven currents, to elucidate and thereby improve our understanding of the processes governing the spatial distribution of sedimentological features, the transport mechanisms of sediments, and the relationship between them. The results demonstrate that the approach outlined in this study has the potential to provide a universal hydro-sedimentological classification scheme., JRC.H.6-Spatial data infrastructures