Volcanoes in Japan can erupt at any timeStaff writer ▼ | October 31, 2014
The recent eruption of Mount Ontake, Japan's worst postwar volcanic disaster, provided graphic evidence of the threat posed by active volcanoes.
Dangerous living 47 volcanoes monitored all the time
The Japan Meteorological Agency and some other expert organizations define volcanoes as mountains created by eruptions during the past 2.6 million years. There are about 450 volcanoes across the nation. The Coordinaing Committee for the Prediction of Volcanic Eruption, the agency's panel of experts, considers a volcano to be active if it has erupted in the last 10,000 years.
There are some 1,500 active volcanoes around the world, including the famous Mount Pinatubo in the Philippines and Mount Tambora in Indonesia.
The 110 active volcanoes that dot the Japanese Archipelago are located throughout the nation, with the northernmost being Mount Moyoro, one of Hokkaido's Etorofu Islands, which is controlled by Russia, and the southernmost the Nikko Seamount, near the island of Iwo Jima.
Of these active volcanoes, 89 are located in eastern Japan, including Mount Fuji, and 21 in western Japan, including Mount Sakurajima.
Toshitsugu Fujii, who heads the prediction committee, noted that the definition of an active volcano is based on its record of eruptions. This is basically the probability approach based on the assumption that a volcano that has erupted in the last 10,000 years is more likely to erupt again, he said.
The Meteorological Agency monitors around the clock 47 volcanoes that are showing signs of strong volcanic activity. ■