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Sea level oscillations are the superposition of many contributions. In particular, tide is a sea level up-down water motion basically depending on three different phenomena: the Earth-Moon-Sun gravitational relationship, the water surface fluid reaction to atmospheric meteorological dynamic, and the Newtonian vertical adjustment of the sea surface...
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INTRODUCTION Water is the basic need of life and the increasing demand of good quality water for irrigation, industry and domestic purpose necessitates its judicious use. Of the total water on earth, only 2.7 % constitutes freshwater which is largely (77%) locked up in the polar icecaps and
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... The starting point of this study is the monitoring of environmental parameters in the port of La Spezia, performed by means of the meteo-mareografic station working in the position 09 • 51 27.52 E, 44 • 05 47.79 N (see Figure 2) and belonging to the National Tidegauge Network managed by ISPRA [39][40][41][42][43][44][45]. ...
... E, 44°05′47.79′′ N (see Figure 2) and belonging to the National Tidegauge Network managed by ISPRA [39][40][41][42][43][44][45]. The instrumentation used consists of a hydrometer and a barometer; the first measures the sea level on the basis of the round trip time taken by a sequence of radar pulses sent from the air towards the sea surface; since the speed of propagation of electromagnetic waves in the air, the round trip time of the pulses, and the position of the radar transducer are known, sea levels are calculated; a typical sampling interval to acquire tide data is at least 10 min. ...
Sea level changes in coastal areas significantly influence port activities (e.g., the safety of navigation). Along Italian coastlines, sea level variations are mainly due to astronomical tides (well known, due to gravitational attraction between Earth, Moon and Sun); however, during the last fifteen years, a high number of “anomalous” tides has been observed: the study of the phenomenon has allowed to attribute its cause to variations in atmospheric pressure (the so-called meteorological tides: sea level drops when atmospheric pressure increases and vice versa); the statistical analysis of acquired data made it possible to evaluate the hydrobarometric transfer factor (a local parameter which represents the correlation between atmospheric pressure changes and consequent sea level variations): it was found that it is usually much larger within gulfs or port basins than offshore areas, where a pressure change of 1 hPa results in a sea level variation of about 1 cm; the statistical analysis described in the following, and aimed at correctly estimating the hydrobarometric transfer factor in harbours, can play a fundamental role in optimizing the management of port waters: its results allow to forecast meteorological tides and therefore future sea level (and depth) variations in a given port basin. The results of the study conducted in the port of La Spezia (North Western Italy) are presented here, together with possible applications on port activities and harbour water management.
... This phenomenon depends on a lot of variables (e.g., the topography of the basin) so, unlike the previous phenomenon, it is not describable by a deterministic law: the statistical correlation between changes of atmospheric pressure (cause) and sea-level variations (effect) is estimated by analysing meteorological events (sea-level changes consequent to atmospheric pressure variations) that occur in a certain location for a long time interval. Once this correlation (named hydro-barometric transfer factor) is known, meteorological tides can be forecasted starting from the knowledge of atmospheric pressure variations [22][23][24][25][26][27][28][29][30]. ...
This article describes research aimed at developing a system able to support local authorities and port communities in optimizing port navigation, avoiding or managing critical situations induced by sea-level variations in harbours and minimizing environmental damages and economic losses. In the Mediterranean basin, sea-level changes are mostly due to astronomical tides, related to the gravitational attraction between Earth, Moon and Sun. Nevertheless, sea-level variations are also influenced by meteorological tides, which are geodetic adjustments of sea surface due to atmospheric pressure variations above a water basin. So, starting from monitoring or forecasting environmental parameters in harbours, the system updates port bathymetric maps based on sea-level variations (acquired in the past, measured in real-time, or expected in the future) and detects hazardous areas for a certain ship moving inside a port at a given moment, by means of the implementation of “virtual traffic lights”. The system was tested on some real situations, including the analysis of maritime accidents (stranding of ships), providing satisfactory results by correctly signalling potentially dangerous areas variable over time. The architecture of the system and results achieved using it in the ports of Livorno and Bari, in Italy, are herewith described.
... The J factors (also called transfer Newtonian factors) formalize the amplitude relationship between the induced phenomenon and of the inducing one [9]. ...
... ssure and of the corresponding varia on of sea level (supported by UEEFRD and several Port Authori es) allowed to calculate J factors for several ports and the respec ve K (delay mes) of the arrival of de wave compensa on (forced) with respect to the transit of the atmospheric pressure change (forcing): hydrobarometric forecas ng of the firstorder [Faggioni et Al. 2013]. Subsequently, with the aim to improve the precision of the measurement and the forecas ng of the phenomenon, a comparison was made between the amplitude and the me of arrival of de wave with the varia on of accelera on of gravity due to the change in weight of the atmosphere: hydrobarometric forecas ng of the secondorder. The experime ...
... To generate alarms when a target is detected, we have developed a software program that processes data acquired by magnetometers and turns on a red light and a beep sound when a magnetic anomaly is identified. Figure 1 shows alarms generated while a diver was crossing the barrier swimming first above the sensors n. 1 and then halfway between n. 2 and n. 3. A multiyear study carried out in several Italian ports allowed us to obtain an estimate of the hydrobarometric transfer factor J ph from atmospheric pressure variations to consequent sea level fluctuations (Newtonian correlation between atmospheric weight variations and sea level adjustments) [Faggioni et al., 2013]. We analyzed many occurrences of this phenomenon (meteorological des, i.e. due to varia ons in atmospheric pressure) in Italian ports (data acquired by means of Italian Na onal Tidegauge Network, managed by ISPRA Italian Ins tute for Environmental Protec on and Research) and for each of them we calculated the value of the hydrobarometric transfer factor as: ...
The knowledge of sea level in harbours is very important to manage port activities (safety of navigation, prevention of ship stranding, optimization of vessel loading, water quality control). In this article we describe the use of a software tool developed to help local authorities and working organizations to optimize navigation and avoid or manage hazardous situations due to sea level changes in port basins. This prototype application, starting from reading data coming from a monitoring station in La Spezia harbour (in North Western Italy), updates dynamically the port bathymetry based on sea level oscillations (measured in the past or real-time, or expected in the near future). Then, it detects potentially dangerous areas for a given ship moving in the basin at a certain time, by means of the idea of “virtual traffic lights”: sea level variations are provided as parameters to the application that performs the updating of the bathymetric map and the subdivision of the harbour in allowed (green)/warning (yellow)/prohibited (red) areas for each ship, based on its draft. The tool can provide a useful support interface to competent authorities to avoid or manage critical situations by detecting hazardous areas for a given vessel at a given time.
In this paper, the advantages achievable from the use of two prototype systems that are being developed to increase safety and security in ports are shown. Both systems start by monitoring environmental parameters in harbors, and then process data acquired. The first system has been conceived to be helpful to port communities (port authorities, pilots) to optimize harbor waterside management (ship’s navigation and cargo, dock performances, boat moorings, refloating of stranded ships, water quality control). By monitoring and processing sea level and atmospheric pressure in port areas, it can help port communities, e.g., to choose the best time when a ship with a certain draft can enter or leave a harbor, or to plan the best route inside the basin for that vessel (port safety). The second system, instead, has been designed for port protection purposes: by monitoring and processing the Earth’s magnetic field below the sea surface in harbors (where the natural field is disturbed by a high artificial component), it is able to detect the possible presence of intruders (e.g., divers) swimming underwater in prohibited areas (port security). Here, the results of monitoring and processing activities of the two systems performed in Livorno and La Spezia harbors are shown (Italy). The processing procedures and the graphical interfaces of the systems are based on applications under development by the research team the author belongs to, by using C# and C++ languages; Matlab environment has been employed for simulations.
This work shows the results achieved using two prototypes of monitoring and processing systems that are being developed with the aim of increasing the safety and the security in harbours. The first one has been designed to help port communities (port authorities, pilots) to manage harbour waterside (optimization of ship’s navigation and cargo, dock performances, boat moorings, refloating of stranded ships, water quality control). Starting from monitoring the sea level and meteorological parameters in harbours, it can help port communities decide, e.g., when a ship with a certain draft can enter or leave the port, or which the best route to follow is (port safety). The second system, instead, deals with the monitoring of the Earth’s magnetic field in port areas for harbour protection purposes, in particular to detect the possible presence of underwater intruders, e.g. divers swimming in restricted areas (port security). The processing procedures of both systems are based not on commercial software, but on applications under development by the research team the author belongs to, by using C# and C++ languages and Matlab environment.
On 26 and 27 June, 2019, the Environment Department of Istituto Nazionale di Geofisica e Vulcanologia (INGV) organized a first internal workshop dedicated to the scientific and technological research on the marine environment. This volume contains the extended abstracts of the presentations given in the workshop.
Antonio Costanza is co-author of the papers on pages 38, 52-53, 88-91, 92-94 and 95-98.
