Mortality Estimation by Causes of Death Due to the 1923 Kanto Earthquake

Abstract

Damage statistics documenting the number of dead and missing due to the 1923 Kanto earthquake are different from each other and the data sources are generally unknown. In fact, the number of more than 142, 000 people, which has been frequently explained as the fatalities in this event, is not on a certain basis. Moreover, it has been understood that the huge fires that followed the earthquake induced most of the death toll. However, the number of collapsed houses was also large in comparison with past earthquakes. Thus it is reasonable to recognize that the collapse of houses was a dominant factor on loss of life as well. In this report, a reliable database showing the number of deaths in each city is newly developed with examination and compilation of damage statistics for the Kanto earthquake. The mortality by causes of death is estimated considering relationships between building damages and human losses, and the death tolls by collapse of houses, fires, tsunamis/debris-flows/landslides and damage in factories are evaluated. The database reveals the Kanto earthquake killed a total of 105, 385 people. Among them, 87% were caused by fires, while more than 10% were dead in collapsed houses. The number of 11, 086 deaths by the collapses is far greater than total death toll by the 1981 Nobi earthquake and by the 1995 Hyogoken-nanbu earthquake. These estimation results indicate that the Kanto earthquake caused all types of earthquake disasters to increase mortality level.