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The Japan Meteorological Agency seismic intensity scale is a seismic scale used in Japan and Taiwan to measure the intensity of earthquakes. It is measured in units of . Unlike the Moment Magnitude Scale (MMS) (a more accurate scale than the outdated Richter Scale),〔()〕 which measures the energy released by the earthquake, the JMA scale describes the degree of shaking at a point on the Earth's surface, and is analogous to the Mercalli intensity scale. The intensity of an earthquake is not totally determined by its magnitude, and varies from place to place; for example, a quake may be described as "shindo 4 in Tokyo, shindo 3 in Yokohama, shindo 2 in Shizuoka". The JMA operates a network of 180 seismographs and 627 seismic intensity meters〔(気象庁 | 震度観測点（全国） )〕〔The Daily Yomiuri, August 23, 2009, p. 2〕 and provides real-time earthquake reports to the media and on the internet.〔(Japan Meteorological Agency | Earthquake Information )〕 == History == Japan experiences approximately 400〔http://www.hinet.bosai.go.jp/about_earthquake/part1.htm Japanese web site; official data of Shindo 1–7 in 1997 to 2006 is 32,244 times, and Shindo 1–3 is 4 to 5 times in a day. Web site of 防災科学技術研究所;National Research Institute for Earth Science and Disaster Prevention=NIED/ Although none of web site is available for basis of 400 times in a day, but 400 times is well told and well assumable number with this data.〕 earthquakes every day, although the vast majority are ''shindo scale'' "0" or less and detectable only using specialist apparatus. The Japan Meteorological Agency (JMA) first assigned a four-stage ''Shindo'' in 1884, with the levels: 微 (faint), 弱 (weak), 強 (strong), and 烈 (violent). In 1898 this scale was changed to a numerical system, assigning earthquakes levels 0–7. In 1908, the levels on this scale were given descriptions, and earthquakes were assigned levels based on their perceived effect on people. This scale was widely used during the Meiji period, and revised during the Shōwa period with the descriptions seeing an overhaul. Following the Great Hanshin earthquake in 1995, the first time an earthquake had received the highest rating of 7 on the scale, levels 5 and 6 were divided in two, giving a total of 10 levels of earthquake: 0–4, weak/strong 5 （５弱、５強）, weak/strong 6 （６弱、６強） and 7. The ''Shindo'' scale has been used in Japan from 1996 without change.〔(気象庁震度階級（明治17年～昭和23年） ) in Japanese〕〔(震度 ) in Japanese〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Japan Meteorological Agency seismic intensity scale」の詳細全文を読む スポンサード リンク
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