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HF radar systems have the potential to measure the wind direction, in addition to surface currents and wave fields. However, studies on HF radar for wind direction determination are rare in the scientific literature. Starting with the results presented in Saviano et al. (2021), we here expand on the reliability of the multiannual wind direction data retrieved over two periods, from May 2008 to December 2010 and from January to December 2012, by a network of three SeaSonde high-frequency (HF) radars operating in the Gulf of Naples (Central Tyrrhenian Sea, Western Mediterranean Sea). This study focuses on the measurements obtained by each antenna over three range cells along a coast–offshore transect, pointing to any potential geographically dependent measurement. The scarcity of offshore wind measurements requires the use of model-generated data for comparative purposes. The data here used are obtained from the Mediterranean Wind–Wave Model, which provides indications for both wave and wind parameters, and the ERA5@2km wind dataset obtained by dynamically downscaling ERA5 reanalysis. These data are first compared with in situ data and subsequently with HF-retrieved wind direction measurements. The analysis of the overall performance of the HF radar network in the Gulf of Naples confirms that the HF radar wind data show the best agreement when the wind speed exceeds a 5 m/s threshold, ensuring a sufficiently energetic surface wave field to be measured. The results obtained in the study suggest the necessity of wind measurements in offshore areas to validate the HF radar wind measurements and to improve the extraction algorithms. The present work opens up further investigations on the applications of wind data from SeaSonde HF radars as potential monitoring platforms, both in coastal and offshore areas.

Intense atmospheric disturbances, which impact directly on the sea surface causing a significant increase in wave height and sometimes strong storm surges, have become increasingly frequent in recent years in the Mediterranean Sea, producing extreme concern in highly populated coastal areas, such as the Gulf of Naples (Western Mediterranean Sea, Central Tyrrhenian Sea). In this work, fifty-six months of wave parameters retrieved by an HF radar network are integrated with numerical outputs to analyze the seasonality of extreme events in the study area and to investigate the performance of HF radars while increasing their distances from the coast. The model employed is the MWM (Mediterranean Wind-Wave Model), providing a wind-wave dataset based on numerical models (the hindcast approach) and implemented in the study area with a 0.03° spatial resolution. The integration and comparison with the MWM dataset, carried out using wave parameters and spectral information, allowed us to analyze the availability and accuracy of HF sampling during the investigated period. The statistical comparisons highlight agreement between the model and the HF radars during episodes of sea storms. The results confirm the potential of HF radar systems as long-term monitoring observation platforms, and allow us to give further indications on the seasonality of sea storms under different meteorological conditions and on their energy content in semi-enclosed coastal areas, such as the Gulf of Naples.

In the Adriatic Sea (Mediterranean Sea), during monitoring of Production Water (PW) discharged from offshore platforms, high contamination levels of metals, PAH, and aliphatic hydrocarbons are detected in the sediment close to some installations. Here, we investigate for the first time, the transport and fate of the total suspended solids (TSS) associated with PW discharged by selected platforms, considering the separation of particulate matter from the water plume. We apply a 3D hydrodynamic model and a Lagrangian module to simulate the dispersion of PW suspended substances, then we relate the numerical results to the sediment contamination measured data. The TSS released with PW determines a negligible contribution along the water column and seems poorly related to the anomalies observed in the sediment contamination levels. This approach paves the way to assess the potential risks arising from TSS discharged with the PW on marine ecosystems and to optimize the environmental monitoring tools.

In recent years increasing attention has been paid to environmental effects that may result from marine dredging and disposal operations. In general, the fine-grained fraction of handled sediments can be dispersed far from the intervention site as a turbidity plume, depending on the specific site and operational parameters. Starting from a literature review, this paper suggests standards for estimating and characterizing the sediment source term, for setting up far-field modeling studies and analyzing numerical results, with the aim of optimizing, also from an economic point of view, the different project, execution and monitoring phases. The paper proposes an integrated modeling approach for simulating sediment dispersion due to sediment handling operations in different marine-coastal areas (off-shore, near-shore and semi-enclosed basins). Attention is paid to the characterization of sediment source terms due to different operational phases (removal, transport and disposal). The paper also deals with the definition of accuracy level of modeling activities, with regard to the main physical processes characterizing the different marine–coastal areas and to the type of environmental critical issues near the intervention site (if any). The main relationships between modeling and monitoring are given for the different design and management phases to support the selection of appropriate technical alternatives and monitoring actions and to ensure the environmental compliance of the proposed interventions.

The aim of this study was to evaluate topographic changes along a stretch of coastline in the Municipality of Borghetto Santo Spirito (Region of Liguria, Italy, north-western Mediterranean) by means of a remotely piloted aircraft system coupled with structure from motion and multi-view stereo techniques. This sector was surveyed three times over 5 months in the fall–winter of 2013–2014 (1 November 2013, 4 December 2013, 17 March 2014) to obtain digital elevation models and orthophotos of the beach. Changes in beach topography associated with storm action and human activities were assessed in terms of gain/loss of sediments and shifting of the wet–dry boundary defining the shoreline. Between the first and second surveys, the study area was hit by two storms (10–11 November 2013 and 21–22 November 2013) with waves approaching from the E–NNE, causing a shoreline retreat which, in some sectors, reached 7 m. Between the second and third surveys, by contrast, four storms (25–27 December 2013, 5–6 January 2014, 17–18 January 2014 and 6–10 February 2014) with waves propagating from the SE produced a general advancement of the shoreline (up to ~5 m) by deposition of sediments along some parts of the beach. The data also reflect changes in beach topography due to human activity during the 2013 fall season, when private beach managers quarried ~178 m 3 of sediments on the emerged beach near the shoreline to accumulate them landwards. The results show that drones can be used for regular beach monitoring activities, and that they can provide new insights into the processes related to natural and/or human-related topographic beach changes.

The action of propeller-induced jets on the seabed of ports can cause erosion and the deposition of sediment around the port basin, potentially significantly impacting the bottom topography over the medium and long term. If such dynamics are constantly repeated for long periods, a drastic reduction in ships' clearance can result through accretion, or the stability and duration of structures can be threatened through erosion. These sediment-related processes present port management authorities with problems, both in terms of navigational safety and the optimization of management and maintenance activities of the port's bottom and infrastructure. In this study, which is based on integrated numerical modeling, we examine the hydrodynamics and the related bottom sediment erosion and accumulation patterns induced by the action of vessel propellers in the passenger port of Genoa, Italy. The proposed new methodology offers a state-of-the-art science-based tool that can be used to optimize and efficiently plan port management and seabed maintenance.

The trophic, chemical and ecological state of a lagoon is strongly influenced by numerous aspects, among which the quantity and quality of the water coming from its drainage basin are a priority. The Source-to-Sea approach directly addresses the linkages between land, water, delta, estuary, coast, nearshore and ocean ecosystems to identify appropriate courses of action to address alterations of key flows, resulting in economic, social and environmental benefits. Hydrodynamic modeling has become a fundamental tool for describing the dynamics of marine environments, and a specific field of development of ongoing research is a detailed representation of the land–coastal–sea fluxes. In the present study, a numerical modeling tool was used in the Venice Lagoon to assess and quantify dominant contributions from the river basin within specific areas of the lagoon. An advective–diffusive model was used to reproduce the transport of passive tracers. The results were analyzed using an automated computational tool, obtaining the average percentage contribution of each input from the drainage basin and mean concentrations of tracer in the different water bodies. Through the proposed methodology, it is possible to support the planning of specific measures, identifying priorities of management intervention and preliminarily exploring different scenarios.

In port areas, sediments resuspension can be critical for the presence of contaminants (such as metals from industrial effluents), which may be dispersed to unpolluted areas under different hydrodynamics forces. In the framework of the interregional project SE.D.RI.PORT (SEdimenti, Dragaggi e RIschi PORTuali) project, the Institute for Environmental Protection and Research (ISPRA) and Regional Agency for Environmental Protection–Liguria (ARPAL) have implemented a numerical model to simulate the sediment plume dynamics for bed levelling operation in the pilot area of La Spezia harbour (Italy). The area is characterized by a diffused pollution and subjected, since the 90s, to different dredging and reclamation activities, as well as monitoring and environmental characterization, providing data for the model. According to sectors references, different modelling tools has been applied to characterize the area interested by sediment plume dynamics, in term of significant variations of suspended sediment concentration (SSC) and sediment deposition rates (DEP). Model results are presented by means of synthetic maps showing the meaningful effects of operations at different water depths and at different key sites in order to support the dredging project and the environmental monitoring planning and optimization.

Successful communication between a teacher and a student is at the core of pedagogy. A well known example of a pedagogical dialog is 'Meno', a socratic lesson of geometry in which a student learns (or 'discovers') how to double the area of a given square 'in essence, a demonstration of Pythagoras' theorem. In previous studies we found that after engaging in the dialog participants can be divided in two kinds: those who can only apply a rule to solve the problem presented in the dialog and those who can go beyond and generalize that knowledge to solve any square problems. Here we study the effectiveness of this socratic dialog in an experimental and a control high-school classrooms, and we explore the boundaries of what is learnt by testing subjects with a set of 9 problems of varying degrees of difficulty. We found that half of the adolescents did not learn anything from the dialog. The other half not only learned to solve the problem, but could abstract something more: the geometric notion that the diagonal can be used to solve diverse area problems. Conceptual knowledge is critical for achievement in geometry, and it is not clear whether geometric concepts emerge spontaneously on the basis of universal experience with space, or reflect intrinsic properties of the human mind. We show that, for half of the learners, an exampled-based Socratic dialog in lecture form can give rise to formal geometric knowledge that can be applied to new, different problems.