RIASSUNTO
ABSTRACT:
GPS Comprehensive Oceanographic Monitoring System (GCOMS) using buoy platform has been developed since 1997. GCOMS technology has already been applied to the nationwide GPS Wave Gauges to monitor 15 locations around the Japanese coast. On the basis of the GCOMS technology, new types of monitoring methods, Smallsized GPS Buoy for coastal area and PVD (Point precise Variance Detection) Wave Monitoring Unit, have been developed. The Smallsized GPS Buoy is characterized by its cost-efficiency and simplicity. The PVD Wave Monitoring Unit based on PVD method can be attached on floating fish-breeding reefs or floating beacons.
INTRODUCTION
Japan, an island nation lying off the east coast of Asia, is surrounded by the sea. Under this geographic feature, the Japanese people have made efforts to take full advantage of ocean resources. On the other hand, due to a number of natural disasters such as tsunami, storm surge, high waves, etc., oceanic observation technology has been studied for many years. In recent year, especially, the demand for monitoring the environment change due to the global warming is growing. GCOMS combining high-accuracy GPS positioning technique with buoy has already been put to practical use in the oceanographic observation domain. The Japan’s Ports and Harbours Bureau, Ministry of Land, Infrastructure, Transport and Tourism(MLIT) has actually applied GCOMS technology to nationwide GPS Wave Gauges since 2006 and 15 GPS wave gauges have already been installed around the Japanese coast. In addition, new types of GCOMS improved in costefficiency, simplicity, usability, etc. have been developed on the social demands. In this paper, the overview and achievements of the GPS Wave Gauges using GCOMS technology are described. Moreover, the Small-sized GPS Buoy for coastal area, featured by its economical advantages and simplicity, as well as the compact Wave Monitoring Unit based on the PVD method, are also introduced.