OS-IS® Sistema sismico per il monitoraggio e la previsione del moto ondoso

Abstract

The European project “Wind, Ports, and Sea”, funded by the European Cross-border Programme “Italy–France Maritime 2007-2013”, aims to improve the safety conditions and to reduce the hazards by monitoring and forecasting the sea-state outside the main ports of the Northern Tyrrhenian and Ligurian Seas. The sea state forecast is done by using a numeric model specifically developed, while the used data are obtained by means of a monitoring system of stations installed in the coast of La Spezia harbor so to perform an inland remote monitoring. This remote monitoring system of the sea, called OSIS ® (Ocean Seismic - Integrated Solution), is a pilot project and will be presented in its main features. The main advantage of the OS-IS® is that it is installed inland and there are no parts in the sea. The key elements of the system are a high sensitivity accelerometers and apposite algorithms for the evaluation of the sea state using the micro-seismic signals on the basis of the mathematical models and the appropriate calibration factors. Actually, since the beginning of the 1900, is well known that the sea waves are sources of a microseismic noise and this phenomenon has been described with more and more precise models since the 1950 by Longuet-Higgins. The OS-IS® system used for "Wind, Ports and Sea" project is made of three micro-seismic stations installed near the La Spezia gulf: each accelerometric station is equipped with a weather station and a data logger that automatically transfers the data to a central server which runs the algorithm of the OS-IS®. In the following will be shortly described the installed systems focusing on its reliability and in the comparison with the traditional monitoring system using buoy. Finally the first measurements will be shown in comparison with those of the conventional method based on the buoys.