Japan and Natural Disasters

Prevention and Risk Management

Jean-Francois Heimburger

• Éditeur: Wiley-ISTE
• Année: 2018
• ISBN:
  9781119549796
• Édition: 1
• Sujet: Technology & Engineering
• Sous-sujet: Environmental Management

Japan is one of those countries most often affected by powerful natural hazards: earthquakes, tsunamis, volcanic eruptions, typhoons, heavy rains, heavy snowfall, tornadoes, etc. The Archipelago is considered a very advanced country in terms of forecasting, prevention and management of natural disasters. A detailed analysis of the reality of recent years is however necessary. In the run-up to the 2020 Olympic Games in Tokyo, among others, a publication on the subject will inform a large number of people wanting to know more about the risks of natural disasters in Japan.

Part 1
Hazards, Risks and Disasters

1
From Hazard to Disaster

“Even if we can’t say that earthquakes, tsunamis or typhoons don’t happen in other Western countries, it is rare that they happen so frequently and cause as much damage as in Japan. […] But it is necessary to consider something which is always forgotten: the intensity of disasters caused by violence of nature becomes stronger as civilization advances.”¹ [TER 11, pp. 11–12]²

Japan is not just a group of islands. It is also an archipelago of natural hazards on which is constructed a society that, over the course of its development, has increased its exposure to disaster risks. Before presenting the different phenomena which regularly affect the country, as well as their human and material consequences, it is necessary to first review the meaning of several key words and their equivalents in the Japanese language.

1.1. Hazard, vulnerability and risk

In the natural domain, a hazard is defined as an event which can occur and cause damage to people and developments as well as to the environment. Although there is no exact translation of this word in Japanese, the term that comes closest is shizen genshô (自然現象, “natural phenomenon”). Hazâdo, taken from the English word “hazard”, is not used in this sense except in hazâdo mappu (ハザードマップ, “hazard map”, “danger map”).

Vulnerability refers to the level of predictable consequences of a phenomenon on society. The equivalent Japanese term is zeijakusei (脆弱性), which indicates a fragile and weak character.

Risk is the result of the combination between hazard and vulnerability. The closest Japanese terms are kikensei (危険性, “dangerousness”) as well as the Anglicism risuku (リスク, “risk”), present in expressions such as saigai risuku (災害リスク, “disaster risk”) at least since the beginning of the 2000s³. The latter term is being used more and more, including by local governments or by the Japan Meteorological Agency.

1.2. Disaster

The word “disaster”, which in the current modern sense refers to an unfortunate event that is abrupt in origin and with numerous victims, has an exact equivalent in Japanese, namely saigai (災害, “disaster”), defined as a “misfortune which arrives in an unexpected way, such as a natural disaster, a fire or an accident” [REY 10, SHÔ 01]. The term saigai is made up of two ideograms. The first and more important uses a dam (巛) on top and fire (火) below, together signifying a large fire disrupting a comfortable life. Here, the dam has a negative meaning, since it is not able to prevent flooding, but to keep life from going smoothly [TÔD 10]⁴. Natural disaster is translated as shizen saigai (自然災害) or tensai (天災), as opposed to jinisaigai (人為災害) and jinsai (人災) which refer to a disaster caused by humans.

As for the terms “calamity”, meaning a great public misfortune, and “curse”, defined as a disastrous thing which seems to be the instrument of divine anger, these are similar to the Japanese word yakusai (厄災), which evokes fear or renunciation in the face of a negative element that human beings are not able to control [YAM 17a].

1 Unless otherwise noted, all translations are the author’s. 2 Torahiko Terada (1878–1935) was a Japanese physicist and writer. 3 The term is used repeatedly in the white paper on disaster prevention published by the Cabinet Office in 2001 [NAI 01]. 4 This interpretation goes against the one presented by certain researchers [PEL 03, MOR 17b], which is based on the fact that the kanji 災 is composed of the pictograms for water and fire, seeming to have confused the element 川 (“river”, “water”) and the element 巛 (“dam”).

2
Earth and Fire

2.1. Earthquakes

Kanto, September 1, 1923. “There’s an ocean of fire in Fukagawa”, Honjô yells to his friend Jirô and then looks toward the sky disturbed by the wind: “The fire will spread. Tokyo is finished!” A little earlier, Jirô, the young hero of Hayao Miyazaki’s animated film The Wind Rises, had found himself on a train when the earthquake occurred. The rails, like the wooden houses, had undulated violently to the rhythm of the propagation of the seismic waves. The train managed to stop without derailing. However, as everyone fled, columns of smoke appeared on the horizon [MIY 13].

“The reason the fires spread so quickly in spite of the profusion of vegetation was that it was noon and that, in every home, the stoves were glowing red with coal”, written by Junichirô Tanizaki in A Tuft of Hair, which appeared in 1926 [TAN 97]. The writer knew something about it, since he experienced the event, which even prompted him, several days later, to move from Kanto to Kansai, a region considered safer at that time.

If the great Kanto earthquake, caused by an earthquake with a magnitude of 7.9 followed by numerous and powerful aftershocks, is widely present in the literature of the 1920s and still on the mind of our contemporaries, as Miyazaki’s masterpiece shows, it is because it was the origin of the worst natural disaster in Japan’s history. There were 105,000 dead, of which 88% would die in the flames. More than 460,000 buildings were completely destroyed. The economic damage represented more than 35% of the GDP [SHI 15, IMA 16].

2.1.1. Japan, principal seismic country

All of Japan’s inhabitants have certainly experienced an earthquake. The world leader in terms of number of earthquakes measured, the Japanese archipelago is located in an area where four tectonic plates meet and continuously shift against each other. The brutal shifting between two rock masses, which causes shocks, can appear in various places: between two plates, such as the earthquake in eastern Japan on March 11, 2011; the interior of a plate, such as the Hokkaido Tôhô-Oki earthquake on October 4, 1994; at shallow depths in Earth’s crust, such as the Kobe...