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Highlights • A surge-tidal, unstructured grid model for pan-European Storm Surge Forecasting. • Satisfactory validation of predictive skill for tidal, surge and total water levels based on 208 tidal gauge stations. • Coupling with tides improves storm surge prediction, especial along the North Sea and the English Channel. • Higher resolution atmospheric forcing improves the predictive skill related to extreme events. Abstract Operational forecasting systems are important for disaster risk reduction. In this work we implement a coupled storm surge and tidal model on an unstructured grid over Europe towards the development of a pan-European Storm Surge Forecasting System (EU-SSF). The skill to predict tidal, surge and total water levels was evaluated based on measurements from 208 tidal gauge stations. Results show satisfactory performance for the two atmospheric forcing datasets tested, a High Resolution Forecast and ERA-INTERIM reanalysis, both provided by the European Center for Medium range Weather Forecast. For tidal predictions, the total RSS is equal to 0.197 m, lower than the values estimated by the global tidal model FES2004, and outperformed only by FES2012 (RSS = 0.05 m), which however is a product of data assimilation. Storm surge validation results show good predictive skill, with 0.04 m < RMSE < 0.21 m and %RMSE within 4%–22%. Coupling with tides results in improved storm surge level predictions, with RMSE reducing by up to 0.033 m. The areas benefiting most from the coupling are the North Sea and the English Channel, resulting in up to 2% reduction of the %RMSE. Increasing the resolution of atmospheric forcing also improves the predictive skill, leading to a reduction of RMSE up to 0.06 m in terms of the extremes, especially in shallow areas where wind is the main driver for surge production. We propose a setup for operational pan-European storm surge forecasting combining tidal levels from the FES2012 model and storm surge residuals from the EU-SSF setup which couples meteorological and astronomic tides. [ABSTRACT FROM AUTHOR]

Abstract: Simulating swash zone morphodynamics remains one of the major weaknesses of beach evolution models. One of the reasons is the limited availability of data on morphological changes at the temporal scales of individual swash events. This paper sets out to present a new hybrid system, consisting of 2D/3D laser scanners and several video cameras, which was designed to monitor swash zone topographic change on a wave-by-wave basis. A methodology is proposed consisting of sensor calibration and several data processing steps, allowing a fusion of different sensors. Such an approach can improve the performance of several field/laboratory, optical technique applications for nearshore hydro- and morpho-dynamic measurements. Digital Elevation Models from a 3D scanner were used in the extrinsic camera calibration procedure and reduced the geo-rectification errors from 0.035m Qt >3.5kgm−1 s−1. Extreme transport swash events became rarer as the morphology was reaching equilibrium. [Copyright &y& Elsevier]

Abstract: This article presents a Matlab-based stereo-vision motion tracking system (SVMT) for the detection of human motor reactivity elicited by sensory stimulation. It is a low-cost, non-intrusive system supported by Graphical User Interface (GUI) software, and has been successfully tested and integrated in a broad array of physiological recording devices at the Human Physiology Laboratory in the University of Granada. The SVMT GUI software handles data in Matlab and ASCII formats. Internal functions perform lens distortion correction, camera geometry definition, feature matching, as well as data clustering and filtering to extract 3D motion paths of specific body areas. System validation showed geo-rectification errors below 0.5mm, while feature matching and motion paths extraction procedures were successfully validated with manual tracking and RMS errors were typically below 2% of the movement range. The application of the system in a psychophysiological experiment designed to elicit a startle motor response by the presentation of intense and unexpected acoustic stimuli, provided reliable data probing dynamical features of motor responses and habituation to repeated stimulus presentations. The stereo-geolocation and motion tracking performance of the SVMT system were successfully validated through comparisons with surface EMG measurements of eyeblink startle, which clearly demonstrate the ability of SVMT to track subtle body movement, such as those induced by the presentation of intense acoustic stimuli. Finally, SVMT provides an efficient solution for the assessment of motor reactivity not only in controlled laboratory settings, but also in more open, ecological environments. [Copyright &y& Elsevier]

Abstract: The present contribution considers the dynamics of beaches occupied by outcropping/buried beachrocks, i.e. hard coastal formations consisting of beach material lithified by in situ precipitated carbonate cements. The dynamics of a Greek microtidal beach with beachrocks (Vatera, Lesbos) are examined through the collection and analysis of morphological and sedimentary field data, a 2-D nearshore hydrodynamic model and a specially constructed 1-D morphodynamic model. The results showed that the beachrock-occupied part of the beach is characterised by distinctive morphodynamics as: (i) its beachface is associated with large slopes; (ii) there is a good spatial correlation between the sub-aerial and shallow submerged mean beach profile and the buried/outcropping upper beachrock surface; and (iii) the seaward margins of the submerged beachrock outcrops are always associated with a ‘scour step’ i.e. a submerged cliff. The results also showed that beachrock outcrops can bias cross-shore sediment exchanges by impeding onshore transport due to the presence of the scour step. In this sense, beachrock outcrops may be considered as offshore transport ‘conduits’ for the beach sediments. A conceptual model of beach sediment transport, based on the field data and the hydrodynamic modelling is proposed. According to this model, fresh beach material from adjacent terrestrial sources is transported alongshore, towards the central part of the embayment, where a littoral transport convergence zone occurs under most wave conditions. There, the laterally supplied sediments are lost offshore. [Copyright &y& Elsevier]

Abstract: This short contribution reports the results of a field study on the nearshore characteristics of waves generated by both conventional and high speed passenger ferries. The field observations took place in the late summer of 2005, at a beach close to the port of Mytilene (Island of Lesbos, Greece), and involved the visual observation of ship waves, using digital video recordings and image processing techniques. The results showed that passage of the fast ferry was associated with a longer, more complex and energetic nearshore event; this event not only did include higher nearshore waves (up to 0.74 m) and was organised in different wave packets, but it was also an order of magnitude longer (∼680 s) than the conventional ferry event. Regarding the effects on beach sediment dynamics, the fast ferry waves were estimated to be very efficient in mobilising the nearshore sediments in contrast to those of the conventional ferry. The fast ferry service appears to generate daily prolonged nearshore events, which contain waves with higher energy than those expected from the normal summer wind wave regime of the area; these events also include some high and very steep waves, which can be particularly erosive. Therefore, fast ferry wakes may have considerable impacts on the seasonal beach sediment dynamics/morphodynamics and the nearshore benthic ecology, as well as they may pose significant risks to bathers, affecting the recreational use of the beaches exposed to fast ferry traffic. Finally, the study has shown that satisfactory field observations of the nearshore characteristics of ship-generated (and wind) waves can be obtained using inshore deployments of calibrated poles, digital video cameras and appropriate image processing algorithms. [Copyright &y& Elsevier]

• A high resolution pan-European storm surge hindcast dataset was produced. • Satisfactory predictive skill on coastal areas assessed against 252 tidal gauge measurements. • High performance of hindcast ability in the open ocean based on altimetry satellite comparison. • Extreme storm surges increase (decrease) in latitudes above (below) 50 °N during the period 1979–2016. • Seasonal extreme SSL variation is particularly strong in the northern part of Europe. This contribution presents the high-resolution Pan-European storm surge (SSL) dataset, ANYEU-SSL, produced with the SCHISM circulation model. The dataset covers 40 years (1979–2018) of SSL data along the European coastline with 3-hour temporal resolution and has been extensively validated for the period spanning from 1979 to 2016, considering the whole time series, as well as for the extreme SSL values. Validation against tidal gauge data shows an average RMSE of 0.10 m, and RMSE below 0.12 m in 75% of the tidal gauges. Comparisons with satellite altimetry data show average RMSE of 0.07 m. SSL trends are estimated as an example of a potential application case of the dataset. The results indicate an overall latitudinal gradient in the trend of the extreme storm surge magnitude for the period 1979–2016. SSLs appear to increase in areas with latitudes >50 °N and to decrease in the lower latitudes. Additionally, a seasonal variation of the extreme SSL, particularly strong in the northern areas, has been observed. The dataset is publicly available and aspires to provide the scientific community with an important data source for the study of storm surge phenomena and consequential impacts, either on large or local scales. [ABSTRACT FROM AUTHOR]

Beach cliffing is a wide-spread characteristic of artificially-replenished beaches, which has many undesirable engineering, environmental and economic consequences. A sedimentological study undertaken on the replenished mixed gravel and sand beach of Hayling Island (southern England) has shown that the persisting beach cliff consists typically of three distinct layers. The textural, geochemical and mineralogical analyses of the deposit showed that the development of the cliff, and particularly the formation of the intermediate, densely-packed layer, could be attributed to a series of processes. Firstly, the techniques used to emplace the recharge material on the beach (i.e. placement by heavy dumper trucks/bulldozers) result in a compaction and grain-fracture of the recharge material, and therefore a denser packing arrangement than that expected by its textural characteristics alone. Secondly, percolating water transfers medium- and fine-grained material to deeper parts of the deposit, resulting in the clogging of the interstices between the gravels and the formation of a densely-packed, poorly-sorted layer. The above processes promote the interactions between the clay minerals of the deposit with [ Ca 2+ ] cations, resulting in the formation of particular cementing materials, such as Calcium Silicate Hydrates (CSH). [ABSTRACT FROM AUTHOR]

The understanding of cross-shore sediment sorting is of primary importance for the design of sand nourishments and for assessing the suitability of the seabed to different ecological species. In this paper, sediment sorting processes were investigated by using a combination of physical and detailed numerical modelling. Data from large-scale wave flume experiments were used to validate a 2DV cross-shore Delft3D model. The model solves coupled short-wave averaged equations for flow, sediment transport, bed composition and bed level change. The infra-gravity wave motions were explicitly resolved. In order to investigate sorting processes, eight sediment fractions were used as well as a layered bed stratigraphy. The effects of different wave conditions (high energetic and more moderate energetic waves) on the morphodynamic profile development and sorting processes were investigated. The Delft3D model reproduced the profile development and bar position very accurately. Additionally, model predictions of sediment sorting across the profile fitted very well with the available observations. The numerical model simulations showed the importance of including short-wave grouping and infragravity wave effects in order to reproduce the cross-shore profile development, especially the breaker bar dynamics and sediment sorting processes. Infragravity waves contribute to larger sediment entrainment and more offshore bar development. Besides leading to a better prediction of the bed profile, infragravity waves also lead to a better prediction of the bed composition. Model results are in agreement with experimental data, showing its capabilities in functioning as a tool to predict sorting processes. [ABSTRACT FROM AUTHOR]