September marks the 100th anniversary of the Great Kanto Earthquake, one of Japan’s most devastating natural disasters. It is crucial for the country to reflect on this milestone and learn valuable lessons for future disaster prevention. The earthquake occurred on September 1, 1923, with Tokyo mistakenly believed to be the epicenter. The actual epicenter was located south of the city, spanning an area 130km long from Kanagawa Prefecture to Chiba Prefecture’s Boso Peninsula. The earthquake had an estimated magnitude of 7.9, followed by several large aftershocks over two days.
Many cities were severely affected, with tremors equivalent to 7 and upper 6 on the Japanese seismic intensity scale. Around 80,000 houses were destroyed, including the iconic 50m-plus Ryounkaku Tower in Tokyo. The death toll and number of missing individuals surpassed 100,000, surpassing the Great Hanshin Earthquake in 1995 and the Great East Japan Earthquake in 2011. The complexity of the disaster contributed to the high casualty numbers.
The majority of victims, approximately 90%, were killed by fire. Tokyo and Yokohama experienced concentrated damage due to the prevalence of cooking fires during lunchtime. Strong winds fueled a rapidly spreading fire that claimed the lives of approximately 38,000 evacuees in Tokyo’s Honjo Ward. The devastating fire lasted nearly two days. The earthquake also triggered a tsunami of up to 12m in Atami, resulting in significant loss of life and destroyed homes. Landslides and cliff collapses in mountainous areas caused additional casualties.
Seismologist Akitsune Imamura had predicted such a catastrophe and issued warnings in a 1905 paper titled “A Simple Method for Mitigating Damage to Life and Property Caused by Earthquakes in Urban Areas.” He emphasized the threat of fires and the importance of earthquake-resistant housing and electric lights. Regrettably, Imamura’s theory was criticized by his university boss and not taken seriously.
The Great Kanto Earthquake consequently led to increased earthquake research in Japan. Imamura himself invested in observation networks in vulnerable regions. While serving as the president of the Seismological Society of Japan, he continued his research until his death in 1948. Despite advancements in observation accuracy and disaster prevention technologies, public awareness and preparedness remain insufficient. A 2021 survey conducted by the Land, Infrastructure, Transport and Tourism Ministry revealed that 39.5% of respondents had made no preparations for natural disasters in the past few years.
Reflecting on personal experience as a reporter during the Great East Japan Earthquake in 2011, it is understandable that many underestimate the possibility of being directly affected by a disaster. However, it is necessary to prepare for unpredictable threats. To raise public awareness, The Yomiuri Shimbun digitally mapped the estimated seismic intensity of the Great Kanto Earthquake for several prefectures. This map allows individuals to understand the past occurrences in their immediate surroundings and encourages disaster prevention consideration.
Although there have been no major earthquakes causing extensive damage to the Tokyo metropolitan area in the past century, there is a 70% probability of a magnitude 7 or greater earthquake within the next 30 years. In addition to collapsing buildings and fires, modern challenges like transportation disruptions and individuals being trapped in elevators must be addressed. By learning from past disasters and taking gradual steps, Japan can strengthen its preparedness for future calamities.
– The Yomiuri Shimbun/ANN
Credit: The Star : News Feed
