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Natural processes and human activities are strongly connected, and sometimes con icting, in the evolution of coastal and transitional environments. The strong anthropic pressure on coastal regions, together with the e ects of a changing climate, demands nowadays more pressingly for e cient tools to characterise and predict the behaviour of such systems in order to de ne appropriate response strategies. This requires a deep understanding of the connections among di erent drivers and di erent scales, a multidisciplinary challenge in which heterogeneous data, approaches and scales need to be framed within a consistent dynamical description. To this aim, a speci c research line was dedicated to “Coastal Vulnerability to Erosion and Sea Level Rise” within the RITMARE Project, supported by the Italian Ministry of University and Research with the purpose of integrating the Italian Marine community in shared research elds in the period 2012-2017. The activities carried out in this framework have been moving along interconnected branches tackling the themes related with sea level rise, ocean modelling, and geomorphological assessment in present conditions and in di erent climate change scenarios, with an eye on the exploitation of marine sand as a strategic resource. In this contribution we review the main outcomes of this multidisciplinary and coordinated research. Besides discussing the advances and the possibilities from state-of-the art technologies and methodologies, we point out that a coordinated use of the described tools should be promoted in the design of survey and monitoring activities, as well as in the exploitation of already collected data. Expected outcomes of this strategy include the implementation of improved policies and infrastructures for coastal protection, anked by reliable short-term forecasting systems and e cient rapid response protocols, in the framework of an integrated coastal planning at the multi-decadal scale.

We depict the relative sea-level rise scenarios for the year 2100 from eight areas of the Italian peninsula. Our estimates are based on the Rahmstorf (2007) and IPCC-AR5 reports 2013 for the RCP-8.5 scenarios (www.ipcc.ch) of climate change, adjusted for the rates of vertical land movements (isostasy and tectonics). These latter are inferred from the elevation of MIS 5.5 deposits and from late Holocene sea-level indicators, matched against sea-level predictions for the same periods using the glacio-hydro-isostatic model of Lambeck et al. (2011). We focus on a variety of tectonic settings: the subsiding North Adriatic coast (including the Venice lagoon), three tectonically stable in Sardinia coastal plains (Oristano, Colledonia and Cagliari coastal plain), Marche (Tronto), Abruzzo (Pescara and Sangro coastal areas), Apulia (Lesina), Granelli (Sicily), and Marina di Campo (Tuscany) and the slightly uplifting Taranto coastal plain. Maps of ooding scenarios are shown on high-resolution Digital Terrain Models mostly based on Lidar data. The expected relative sea-level rise by 2100 will change dramatically the present-day morphology, potentially ooding up to about 6000 km2 of coastal plains at elevations close to present-day sea level. The subsequent loss of land will impact the environment and local infrastructures, suggesting land planners and decision makers to take into account these scenarios for a cognizant coastal management. Our method developed for the Italian coast can be applied worldwide in other coastal areas expected to be a ected by marine ingression due to global climate change.

The increasing awareness of the potential threats acting on the coastal regions, combined with the intense anthropic pressure and the broad variety of socio-economic drivers acting on these systems, bestowed progressively stronger emphasis to the development of sound planning and management policies. The assessment and the formulation of plans for the response to coastal morphological vulnerability is a multidisciplinary challenge, in which different typology of information, approaches and scales need to be integrated and framed within a consistent dynamical description. To this aim, within the RITMARE National Flagship Project, a specific research line on “Coastal Vulnerability to Erosion and Relative Sea level rise in climate change scenarios” was activated with reference to the Adriatic-Ionian region (Eastern Mediterranean Sea). The activities, supported by the Italian Ministry of University and Research 2016-18, move along three interconnected branches, namely: 1) Assessment of vulnerability to relative sea level rise in the Adriatic-Ionian region, in present conditions and in different climate change scenarios; 2) Development of high-resolution oceanographic modelling tools for the description of meteo-marine climate and sediment transport at different scales and rapid response intervention protocols for the evaluation of the impact of erosive events on sandy sediments; 3) Identification of possible geomorphological setting scenarios and definition of intervention strategies, with special care to the exploitment of marine sand as a strategic resource. The work provides an overview of the strategy underlying the Research Line and present preliminary results and main achievements. Next steps will be aiming to pave the way towards a road map for an integrated observational and modelling approach for monitoring and managing the erosion and marine ingression risk throughout Italian coasts, striving to bridge the cultural and methodological gaps between the scientific and administrative sectors active in the coastal management field.

The increasing quality and quantity of information provided by Copernicus, the European Union program funneling Earth observation and in-situ data into a broad set of information services, offer the possibility to analyze and predict coastal meteo-oceanographic processes at an unprecedented level. The combination of ocean/atmosphere/land observations made available in particular from the Sentinel 1, 2 and 3 satellites, aligned with the capabilities of an increasing number of high-resolution numerical imaging systems within the Copernicus Marine Environment Monitoring Service (CMEMS) catalog, will enable users to get access to improved representations of the coastal environment. Moreover, by adding periodic bathymetric updating that may be derived from Sentinel images and incorporating new data assimilation routines, it will become possible to achieve a new level of analysis for coastal seas, with satellite oceanography constraining models and supporting downstream applications. The EU has recently funded the project 'Copernicus Evolution and Applications with Sentinel Enhancements and Land Effluents for Shores and Seas' (CEASELESS) under the EU initiative Horizon 2020.

Many studies have focused on the SST role and effect in convective and highly-localized intense events that originate nearby coastal areas. This specific case study deals with a "flash-flood" event that took place in the Venice lagoon region on September 26, 2007. As described by Davolio et al. (2009), the whole event was due to the convergence between dry and cold air coming from the Alps with warmer and more humid air traveling from the south Adriatic. The clash of these two different air masses happened to be near the coast line, and activated an intense thunderstorm. The storm activity persisted in the generation area for about 6 hours and caused accumulated precipitation around 340 mm over localized area. The purpose of this work is the detailed study of this event with the aid of the modeling suite COAWST (Couple Ocean Atmospheric Wave Sediment Transport system), in order to identify the importance of the various oceanic components: Sea Surface Temperature (SST), mixed layers depth and waves. COAWST provides the coupling of WRF (Weather Research ad Forecasting) atmospheric model, ROMS (Regional Oceanographic Model) ocean model and SWAN (Simulating Wave in Nearshore) wave model. The configuration of the WRF grid is composed by 3 domains at 9 km-3 km-1km of horizontal resolution. ROMS and SWAN models were run at a 1 km resolution with computational grid that cover all the Adriatic Sea. Using a standard configuration, the first phase of the study used WRF in "standalone model", using the SST obtained from the spectrum-radiometer RTG_SST at 8.3 km resolution. As a second step, the same WRF numerical configuration used WRF received the SST derived from "uncoupled" ROMS simulation (produced by a long "spin-up" over the same grid used for the coupling at 1 km of horizontal resolution). In the third stage of the work, coupled numerical runs WRF-ROMS (run AO) and WRF-ROMS-SWAN (run AOW) were performed. The results suggests that the use of high-resolution SST is a good approach to increase the performance of the models but only coupled numerical runs can reproduce vertically both the deep convection process that characterize the event (showing high vertical velocities even in the higher atmosphere) and the reflectivity high values, structured in a single cell in the area of the event. Humidity in higher levels suggests that uncoupled runs maintain a moisture distribution above the PBL characterized by a dry-air tongue, that limits the convection. Differently, in the coupled runs not only the humidity distribution above the PBL is evident, but values within the PBL as well are well marked. We can therefore conclude that coupled numerical models can represent a valid support for the accurate forecast of such extreme events, at least in proximity of coastal regions. They can indeed provide a more energetically consistent system, capable of transferring more heat and moisture in the lower and medium atmosphere. However, further analysis are required to confirm the findings here discussed. Numerical runs were performed thanks to the CINECA grant ISCRA C "COMARE".

The increasing awareness of the potential threats acting on the coastal regions, combined with the intense anthropic pressure and the broad variety of socio-economic drivers acting on these systems, bestowed progressively stronger emphasis to the development of sound planning and management policies. The assessment and the formulation of plans for the response to coastal morphological vulnerability is a multidis- ciplinary challenge, in which different typology of information, approaches and scales need to be integrated and framed within a consistent dynamical description. To this aim, within the RITMARE National Flagship Project, a specific research line on "Coastal Vulnerability to Erosion and Relative Sea level rise in climate change scenarios" was activated with reference to the Adriatic-Ionian region (Eastern Mediterranean Sea). The activities, supported by the Italian Ministry of University and Research 2016-18, move along three interconnected branches, namely: 1) Assessment of vulnerability to relative sea level rise in the Adriatic-Ionian region, in present conditions and in different climate change scenarios; 2) Development of high-resolution oceanographic modelling tools for the description of meteo-marine climate and sediment transport at different scales and rapid response intervention protocols for the evaluation of the impact of erosive events on sandy sediments; 3) Identification of possible geomorphological setting scenarios and definition of intervention strategies, with spe- cial care to the exploitment of marine sand as a strategic resource. The work provides an overview of the strategy underlying the Research Line and present preliminary results and main achievements. Next steps will be aiming to pave the way towards a road map for an integrated observational and modelling approach for monitoring and managing the erosion and marine ingression risk throughout Italian coasts, striving to bridge the cultural and methodological gaps between the scientific and administrative sectors active in the coastal management field.

In this work we assess the quality of the wind fields provided over the Adriatic Sea by the Regional Climate Model COSMO-CLM with reference to a control (CTR) period from 1971 to 2000 and to a future period from 2071 to 2100 under IPCC RCP 8.5 scenario (SCE), focusing on the implications for wave climate characterisation. Model skills have been assessed by comparing CTR results in terms of gross statistical properties and storm features against wind data from coastal observatories along the whole Italian Adriatic coast, showing a satisfactory capability of capturing the main features of mean observed seasonal variability. Significant achievements with reference to existing climatological models have been observed especially in terms of wind directionality, with unprecedented performances in reproducing the bimodal dominance of Bora (from northeast) and Sirocco (from southeast) in the northern basin, and the typical patterns of Bora jets flowing from the mountain ridges enclosing the Adriatic Sea on its eastern side. Future projections generally confirm the tendency to a decreasing energy trend envisaged by previous studies, with a more marked effect for extreme events in the northern basin. Based on the comparison between climatological wind fields and the results of a SWAN wave model run forced by COSMO-CLM, we also define and test a criterion for a rapid identification of some relevant case studies for dedicated wave modelling experiments, without the need of running entire climatological wave simulations. This permits to focus the analysis of climatological oceanographic extreme events to a limited number of selected cases, allowing remarkable saving of computational effort especially if an ensemble approach is desired.

An extremely intense precipitation event stroke the area between the Alps and the Venice Lagoon in the early hours of September 26, 2007. Precipitations exceeding 320 mm were recorded during the short period comprised between 06 UTC and 12 UTC, in an area close to Venice and its inland area (Mestre). This was the result of a mesoscale convective system formed in a convergence area between a north-easterly wind coming from the Alps and a south-easterly one over the Adriatic sea. In this study we describe the flash-flood event using the modeling suite COAWST (Couple Ocean Atmospheric Wave Sediment Transport system), exploring the importance of various oceanic components (Sea Surface Temperature, mixed layers depth, waves, etc.). COAWST is a complex framework that couples WRF (Weather Research ad Forecasting) atmospheric model, ROMS (Regional Oceanographic Model) ocean model and SWAN (Simulating Wave in Nearshore) wave model. The configuration of the WRF grid is composed by 3 domains respectively at 9 km, 3 km, and 1km of horizontal resolution. ROMS and SWAN models were run at a 1 km resolution with computational grid that covers all the Adriatic Sea. In the first phase of the study we used WRF in "standalone mode", using the SST obtained from the spectrumradiometer RTG_SST at 8.3 km resolution. As a second step, the WRF model received the SST derived from the oceanographic model "MyOcean" at 1 km of horizontal resolution, and the best physical configuration was explored by changing schemes of cumulus, microphysics, Planetary Boundary Layer, radiation and soil type and employing the basic Ocena Mixed Layer available in WRF. In the last stage of the work, the best physical configuration identified was then used within the COAWST coupled system, namely WRF-ROMS and WRF-ROMS-SWAN. Results suggest that the use of high resolution SST is necessary in order to realistically simulate the wind direction above the sea, and therefore the position and the intensity of the convergence line that generates the phenomenon. The over/under estimation of the SST in the basin area changed the rotation of the winds and consequently the position of the event. Also, the mixed layer depth was shown to play a key role in the localization of the phenomenon and its intensity, a fact that suggested the use of the coupled model. Coupled model results highlighted that, especially in coastal areas where satellite data are often of poor quality, extreme events may be simulated more accurately both in time and position. Numerical runs were performed thanks to the CINECA grant ISCRA C "CReMinO" and "COMARe".

Cold Air Outbreaks (CAOs) over shallow seas may lead to dense water formation episodes, enhancing water, heat, nutrient and sediment exchanges across the continental margin, with associated seabed reshaping. During winter 2012, a CAO episode characterised by exceptional intensity stroke the northern Adriatic Sea, one of the most effective cool engines driving the Mediterranean circulation, providing a paramount opportunity for an integrated investigation of dense shelf water dynamics. In the present study, we describe this event using a fully coupled modeling approach exploring the effects of mutual interactions among atmosphere, ocean currents and sea surface waves, usually not completely accounted for, in the resulting dense water formation. Whilst atmospheric fields appear to be marginally affected by coupled dynamics in the present case, implications for sea surface elevation and circulation are far from negligible. Measurements collected in the northern Adriatic Sea showed that a physically consistent description of energy exchanges between ocean and atmosphere provides an improved estimate of heat fluxes and of air and sea temperatures. In addition, the explicit inclusion of wave action within the modeling system further enhances the modulation of air-sea exchanges and the propagation of its effect along the water column, resulting in a different intensity of northern Adriatic gyres and in different water fluxes flowing through the formation basin. Through these main controls on the water volume involved in the densification process and on the intensity of momentum input and cooling, a coupled modeling strategy accounting for atmosphere-waves-currents interactions can turn out to be crucial for improving the quantification of thermohaline properties and energy content, newly formed dense water mass, and provide a better description of its migration pathways and rates of off-shelf descent.

Coastal and shoreline management increasingly needs to consider morphological change occurring at decadal to centennial timescales, especially that related to climate change and sea-level rise. This requires the development of morphological models operating at a mesoscale, defined by time and length scales of the order 10(1) to 10(2) years and 10(1) to 10(2) km. So-called 'reduced complexity' models that represent critical processes at scales not much smaller than the primary scale of interest, and are regulated by capturing the critical feedbacks that govern land form behaviour, are proving effective as a means of exploring emergent coastal behaviour at a landscape scale. Such models tend to be computationally efficient and are thus easily applied within a probabilistic framework. At the same time, reductionist models, built upon a more detailed description of hydrodynamic and sediment transport processes, are capable of application at increasingly broad spatial and temporal scales. More qualitative modelling approaches are also emerging that can guide the development and deployment of quantitative models, and these can be supplemented by varied data-driven modelling approaches that can achieve new explanatory insights from observational datasets. Such disparate approaches have hitherto been pursued largely in isolation by mutually exclusive modelling communities. Brought together, they have the potential to facilitate a step change in our ability to simulate the evolution of coastal morphology at scales that are most relevant to managing erosion and flood risk. Here, we advocate and outline a new integrated modelling framework that deploys coupled mesoscale reduced complexity models, reductionist coastal area models, data-driven approaches, and qualitative conceptual models. Integration of these heterogeneous approaches gives rise to model compositions that can potentially resolve decadal- to centennial-scale behaviour of diverse coupled open coast, estuary and inner shelf settings. This vision is illustrated through an idealised composition of models for a similar to 70 km stretch of the Suffolk coast, eastern England. A key advantage of model linking is that it allows a wide range of real-world situations to be simulated from a small set of model components. However, this process involves more than just the development of software that allows for flexible model coupling. The compatibility of radically different modelling assumptions remains to be carefully assessed and testing as well as evaluating uncertainties of models in composition are areas that require further attention. (C) 2015 Elsevier B.V. All rights reserved.

The coasts of the Mediterranean Sea are dynamic habitats in which human activities have been conducted for centuries and which feature micro-tidal environments with about 0.40 m of range. For this reason, human settlements are still concentrated along a narrow coastline strip, where any change in the sea level and coastal dynamics may impact anthropic activities. In the frame of the RITMARE and the Copernicus Projects, we analyzed light detection and ranging (LiDAR) and Copernicus Earth Observation data to provide estimates of potential marine submersion for 2100 for 16 small-sized coastal plains located in the Italian peninsula and four Mediterranean countries (France, Spain, Tunisia, Cyprus) all characterized by different geological, tectonic and morphological features. The objective of this multidisciplinary study is to provide the first maps of sea-level rise scenarios for 2100 for the IPCC RCP 8.5 and Rahmstorf (2007) projections for the above affected coastal zones, which are the locations of touristic resorts, railways, airports and heritage sites. On the basis of our model (eustatic projection for 2100, glaciohydrostasy values and tectonic vertical movement), we provide 16 high-definition submersion maps. We estimated a potential loss of land for the above areas of between about 148 km2 (IPCC-RCP8.5 scenario) and 192 km2 (Rahmstorf scenario), along a coastline length of about 400 km.

This work presents the results of the numerical study implemented for the natural area of Lido di Spina, a touristic site along the Italian coast of the North Adriatic Sea, close to the mouth of River Reno. High-resolution simulations of nearshore dynamics are carried out under climate change conditions estimated for the site. The adopted modeling chain is based on the implementation of multiple-nested, open-source numerical models. More specifically, the coupled wave-2D hydrodynamics runs, using the open-source TELEMAC suite, are forced at the offshore boundary by waves resulting from the wave model (SWAN) simulations for the Adriatic Sea, and sea levels computed following a joint probability analysis approach. The system simulates presentday scenarios, as well as conditions reflecting the high IPCC greenhouse concentration trajectory named RCP8.5 under predicted climate changes. Selection of sea storms directed from SE (Sirocco events) and E-NE (Bora events) is performed together with Gumbel analysis, in order to define ordinary and extreme sea conditions. The numerical results are here presented in terms of local parameters such as wave breaking position, alongshore currents intensity and direction and flooded area, aiming to provide insights on how climate changes may impact hydrodynamics at a site scale. Although the wave energy intensity predicted for Sirocco events is expected to increase only slightly, modifications of the wave dynamics, current patterns, and inland flooding induced by climate changes are expected to be significant for extreme conditions, especially during Sirocco winds, with an increase in the maximum alongshore currents and in the inundated area compared to past conditions. © 2018 by the authors.