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Giovanni Battista Rossi, Francesco Crenna, Marta Berardengo, Vincenzo Piscopo, Antonio Scamardella
Data processing for the accurate evaluation of combined wind sea and swell spectra

The reliable monitoring of sea state parameters is a key factor for weather forecasting, as well as to ensure the safety of ship and navigation. In current analysis different spectrum estimation techniques are applied to random wave signals, generated from a theoretical wave spectrum obtained by combining both wind sea and swell components, with different significant wave heights and peak periods. Hence, the proposed spectrum resembling methods are applied in order to compare the relevant performances, with reference to both short and long-time durations of the considered wave signal.

Silvia Pennino, Antonio Angrisano, Salvatore Gaglione, Anna Innac, Vincenzo Piscopo, Antonio Scamardella
Sea state monitoring based on ship motion measurements onboard an icebreaker in the Antarctic waters

A new wave spectrum resembling procedure is applied to detect the sea state parameters, namely the wave peak period and the significant wave height based on the analysis of heave and pitch motion time series, obtained by on board measurements. The outlined procedure is applied to Laura Bassi oceanographic ship, assumed as reference vessel. Heave and pitch motion time histories are evaluated from the survey of the amplitud es of the vessel motions, starting from different sensors measures collected by a smartphone located on board the vessel. T he obtained results were compared with the weather forecast data provided by the global WAM (GWAM) model.

Jacek Paziewski, Giovanni Pugliano, Umberto Robustelli
Performance assessment of GNSS single point positioning with recent smartphones

The new generation of Android smartphones are equipped with high performance Global Navigation Satellite System (GNSS) chips. These new chips are capable of tracking dual frequency multi constellation data. Moreover, starting from version 9 of Android users can disable the duty cycle power saving option, thus it is feasible to acquire good quality raw carrier-phase measurements. Nevertheless, there is still a need to evaluate the accuracy, which may be reached with current smart devices in a standard navigational solution. In this work we assessed the performance of GPS + Galileo single point positioning of three recent smartphones, namely Xiaomi Mi 8, Xiaomi Mi 9 and Huawei P30. The best positioning accuracy, in terms of horizontal root mean square error (DRMS), was obtained by Huawei P30 with a DRMS of 4.46 m. Xiaomi MI8 shows very similar performance (4.56 m of DRMS) but these results were subject to outliers. Finally Xiaomi Mi9 shows a DRMS of 7.26 m, and therefore demonstrates the poorest accuracy among tested smart devices.

Matteo Cutugno, Giovanni Pugliano, Umberto Robustelli
Developing a low-cost GNSS/IMU data fusion platform for boat navigation

Methods of measuring a vessel's motioninvolve the use of expensive and complex Inertial Navigation Systems (INS). Cargo or passenger transport ships can afford the implementation of such systems while private small boat market has been cut off. The alternatives for small boat INS navigation are few. This paper investigates the potentiality of GNSS/IMU data fusion, experimenting low-cost hardware like Aceinna openIMU 300ZI and a GNSS receiver based on u-blox ZED-F9P module. The final goal is to build a lowcost self-powered system and assess the performance in small boats navigation tests. To address this goal the INS shall be light-weight, cost-effective, and easy to install.

Nikos Georgiou, Paolo Stocchi, Alessio Rovere, Elisa Casella
Reconstructing past sea level through notches: Orosei Gulf

A tidal notch with a maximum height of 10.5 m and almost 60 km of lateral extent was carved during the Last Interglacial (127-116 ka BP) along the West-Sardinian coast, in the Orosei Gulf. We present the results of the detailed mapping of the Orosei tidal notch using the Structure from Motion Multi-View Stereo (SfM-MVS) reconstruction method. Although its geometry is laterally constant, the notch depth differs due to local factors. Results of SfM-MVS reconstructions, together with local parameters, were used as input in a geometric model that simulates the notch shape based on randomly sampled relative sea-level curves. The modeled profiles best matching with the real shape of the notch are those characterized by a bimodal geometry. Extracting information from this rocky imprint is considered crucial to better understand past changes in sea level, which are in turn significant to better gauge sea-level variations in warmer climate conditions.

Silvio Del Pizzo, Antonio Angrisano, Salvatore Gaglione, Salvatore Troisi
Assessment of shoreline detection using UAV

The shoreline is an important feature of the costal morphology. Several methodologies are used to detect such line. In this paper a photogrammetric approach was applied to achieve both an accurate shoreline detection and a DTM (Digital Terrain Model) of the coast using Structure from Motion (SfM) algorithms. The goal of this method is to extract the shoreline from an accurate three-dimensional model of the coast. The proposed approach was performed using an Unmanned Aerial Vehicle (UAV) equipped with a digital camera. In order to avoid regrettable deformations on the 3D model several Ground Control Points were located on the scene, furthermore a precision assessment was performed using check points. The obtained result was compared with a classic RTK-GNSS survey of the shoreline performed by a skilled operator.

Pietro Patrizio Ciro Aucelli, E. Gagliardi, Gaia Mattei, F. Napolitano, G. Pappone, M. Pennetta, Maria Francesca Tursi
Morphological responses to relative sea-level changes along Procida coast (Gulf of Naples, Italy) during the last 6.5 Ky

In this research, the morpho-evolutive trend of sea cliffs placed in the volcanic island of Procida was investigated. The entire perimeter of the island is bordered by cliffs, which in some cases are connected to narrow shore platforms sloping slightly towards the sea. The presence of different orders of submerged paleo-shore platforms suggests different phases of sea-level stand and related coastal response. Mapping these platforms, together with the interpretation of archaeological and geomorphological markers allowed defining the shoreline evolution of Procida Island during the last 6.5 ky. The paleo sea levels deduced from these indicators were compared with the eustatic sea-level curve proposed demonstrating that Procida coastal area was affected by an overall subsiding trend since the Mid-Holocene, which probably occurred intermittently or with variable intensity over time. By reconstructing the position of the ancient shorelines related to the three orders of platforms, the retreating rates of the cliffs bordering the area were calculated.

Gianluigi Di Paola, Pietro Patrizio Ciro Aucelli, Fabio Matano, Angela Rizzo, Ettore Valente
Risk assessment and management strategies to sea level rise along the Sele River mouth (southern Italy)

Rising sea level due to global warming increases the need to analyse coastal risk to conceive management and adaptation strategies aimed at coping with potential marine impacts. In this context, this study presents future scenario of inundation risk along a strategic coastal area located in the Campania Region (southern Italy): the Sele River mouth. This zone is characterized by low topography and relevant subsidence rates that make it prone to be impacted by sea level rise. Expected local sea level for the year 2065 has been evaluated coupling the global IPCC projection with local subsidence trends. Once the risk has been evaluated as a combination of hazard and exposure, a set of management strategies, which include both operative Best Management Practises (BMPs) and monitoring actions, have been suggested and applied on the tested area.

Claudia Caporizzo, Pietro Patrizio Ciro Aucelli, Ignacio Galán Ruffoni, Francisco Javier Gracia Prieto, Celia Martín Puertas, Gaia Mattei, Paolo Stocchi
Estimating RSL changes in the Northern Bay of Cádiz (Spain) during the late Holocene

The Bay of Cádiz (SW Spain) is an example of long historical human occupation of a typical estuarine saltmarsh environment affected by notable historical changes that have conditioned the sedimentary evolution of emerged and submerged zones. This study aims to present new data regarding the RSL position during the late Holocene within the Northern bay of Cádiz. Bibliographic d ata coming from boreholes carried out in the study area were combined with the analysis of a new core. RSL positions, extracted from depositional sea level index points were calculated from saltmarshes and tidal deposits dated between 3.0 2.0 ky BP. Comparing these data with the new eustatic sea level curve of the Bay of Cádiz carried out in this research, we observed that, during the last 3.0 ky BP, the sector has been affected by prevailing subsidence ranging between 0.9 m and 4.3 m.

Michele Gristina, Tamara Lazic, Federico Quattrocchi, Giuseppe Corriero, Frine Cardone, Cataldo Pierri
Evaluation of environmental stressors for a population of the long-snouted seahorse Hippocampus guttulatus through an innovative Citizen Science approach

In this paper we describe the sudden decrease of a Hippocampus guttulatus population in the Mar Piccolo di Taranto (MPT) (South-east Italy) under the combined effect of fishing activities and illegal trade. Until recently, the Mar Piccolo of Taranto has hosted one of the most interesting and large longsnouted seahorse population of the Mediterranean sea. However, as of 2016, the density of H. guttulatus population has shown a sudden and dramatic decrease. Disclosure and report of an online traffic of seahorses from Italy to China (https://veraleaks.org) occurred in February 2019 prompted us to carry out interviews with the main stakeholders operating in the Mar Piccolo of Taranto. The aim of this paper is to evaluate the extent of this illegal trade and the potential effects on the seahorses population.

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