In response to the recommendation of the Council for Science and Technology (Subdivision on Geodesy and Geophysics), the National Research Institute for Earth Science and Disaster Resilience (NIED) constructed a network of stations to observe 11 volcanoes: Tokachidake, Usuzan, Tarumaesan, Hokkaido-Komagatake, Iwatesan, Kusatsu-Shiranesan, Asamayama, Asosan, Kirishimayama, Unzendake, and Kuchinoerabujima. At each new station, a borehole seismograph and tiltmeter, a broadband seismograph, and a GNSS (GPS) were installed. Now, NIED has established 55 stations at 16 volcanoes, adding five volcanoes, namely, Izu- Oshima, Miyakejima, Ogasawara Iwoto, Mt. Fuji and Nasu-dake, and has constructed a new volcano observation network linking the 11 original volcanoes. NIED calls the combination of the new and earlier network the fundamental volcano observation network (V-net).

Under a fully open policy, data from the borehole seismographs and tiltmeters, broadband seismographs, rain gauges, barometers,and quartz thermometers in the pressure vessels of the borehole seismographs and tiltmeters are distributed to institutes such as the Japan Meteorological Agency and universities in real time over NIED’s conventional seismic observation data distribution system. GNSS (GPS) data are regularly distributed to relevant research institutes, such as the Geospatial Information Authority of Japan, using file transfer protocol (FTP). In addition, since everyone can use these data for the promotion of volcano research and volcanic disaster prevention, it is now possible to view seismic waves and download data from NIED’s website.

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