There have been many devastating earthquakes in Japanese history. A multitude of factors determine the scale of the destruction and casualties claimed by these calamitous phenomena, most prominently, in the case of Japan, the risk of tsunami. Magnitude alone doesn't give the full picture, as we can see on the visualisation below, in which we compare the magnitude and casualties of the most destructive earthquakes in Japan over the last 1,000 years.
each circle is a magnitude
The Richter magnitude scale is logarithmic, meaning that each consecutive magnitude represents the release of energy many times greater than the previous one (about 32 times greater). Therefore, a magnitude 9.0 earthquake releases over a million times as much energy as a magnitude 5.0 earthquake. We represented this exponential increase by making the radius of each magnitude circle twice bigger than the preceding one.
one circle represents 1000 deaths
Numbers are approximate as they vary by source. We therefore chose a representation that shows the scale of each disaster rather than exact numbers.
Tōhoku earthquake
東北地方太平洋沖地震
March 11, 2011
magnitude: 9.1
deaths: 16,000
Great Hanshin earthquake
兵庫県南部地震
January 17, 1995
magnitude: 7.3
deaths: 6,400
Great Kantō earthquake
関東大震災
September 1, 1923
magnitude: 8.3
deaths: 140,000
Sanriku earthquake
明治三陸地震
June 15, 1896
magnitude: 8.5
deaths: 22,000
Mino–Owari earthquake
美濃・尾張地震
October 28, 1891
magnitude: 8
deaths: 7,300
Nankai earthquake
安政南海地震
December 24, 1854
magnitude: 8.4
deaths: 10,000
Nagano earthquake
善光寺地震
May 8, 1847
magnitude: 7.3
deaths: 8,600
Unzen earthquake and tsunami
島原大変肥後迷惑
May 21, 1792
magnitude: 6.4
deaths: 15,000
Great Yaeyama Tsunami
八重山地震
April 24, 1771
magnitude: 7.4
deaths: 13,000
Hōei earthquake
宝永地震
October 28, 1707
magnitude: 8.6
deaths: 5,000
Nankai earthquake
慶長大地震
February 3, 1605
magnitude: 7.9
deaths: 5,000
Nankai earthquake
明応地震
September 20, 1498
magnitude: 8.6
deaths: 31,000
Kamakura earthquake
鎌倉大地震
May 27, 1293
magnitude: 7.1
deaths: 23,000