Geography of Japan - Natural Hazards

Natural Hazards

Ten percent of the world's active volcanoes—forty in the early 1990s (another 148 were dormant)—are found in Japan, which lies in a zone of extreme crustal instability. As many as 1,500 earthquakes are recorded yearly, and magnitudes of 4 to 7 in magnitude are common. Minor tremors occur almost daily in one part of the country or another, causing slight shaking of buildings. Major earthquakes occur infrequently; the most famous in the twentieth century was the great Kantō earthquake of 1923, in which 130,000 people died. Undersea earthquakes also expose the Japanese coastline to danger from tsunamis (津波?) and tidal waves. On March 11, 2011 the country was subject to a devastating magnitude 9.0 earthquake and a massive tsunami as a result. The March 11 quake was the largest ever recorded in Japan and is the world's fourth largest earthquake to strike since 1900, according to the U.S. Geological Service. It struck offshore about 371 kilometres (231 mi) northeast of Tokyo and 130 kilometres (81 mi) east of the city of Sendai, and created a massive tsunami that devastated Japan's northeastern coastal areas. At least 100 aftershocks registering a 6.0 magnitude or higher have followed the main temblor. At least 15,000 people died as a result.

Japan has become a world leader in research on causes and prediction of earthquakes. The development of advanced technology has permitted the construction of skyscrapers even in earthquake-prone areas. Extensive civil defence efforts focus on training in protection against earthquakes, in particular against accompanying fire, which represents the greatest danger.

Another common hazard are several typhoons that reach Japan from the Pacific every year and heavy snowfall during winter in the snow country regions, causing landslides, flooding, and avalanches.