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| Japan Meteorological Agency
The Japan Meteorological Agency (JMA) has an abundance of information on weather and natural disasters in Japan (in English!) You can find maps of, and information on, recent earthquakes; weather updates, warnings about typhoons, etc. Maps of recent earthquakes will show the gintensityh of tremors (this is different to the gmagnitudeh of an earthquake). The JMA seismic intensity scale indicates the strength of earthquakes. Unlike the Richter magnitude scale (which measures the total magnitude of the earthquake, and represents the size of the earthquake with a single number) the JMA scale describes the degree of shaking at a point on the Earth's surface. As a result, the measure of the earthquake varies from place to place. Intensity is measured in units of shindo (kx seismic intensity, literally "degree of shaking"). So, a given quake may be described as "shindo 4 in Tokyo, shindo 3 in Yokohama, shindo 2 in Shizuoka". JMA Intensity Scale: Intensity 0 Tremors cannot be felt. Intensity 1 String hanging from a ceiling light will swing. Intensity 2 Some people can feel the tremors even when asleep. Intensity 3 Most people can feel the tremors. Intensity 4 Things fall over Intensity 5 (weak) Things on top of a table will fall over. Intensity 5 (strong) Cracks appear and concrete walls collapse. Intensity 6 (weak) Homes are crushed; there are cracks in the road. Intensity 6 (strong) Buildings lean on one side and telegraph poles fall over. Intensity7 Buildings fall over. |