Will the ‘Nankai Great Earthquake’ Occur in 100-150 Year Cycles? ‘Major Earthquake Warning’ After the Miyazaki Earthquake
“230,000 deaths and missing persons expected when it occurs”… 10 times the damage from the 2011 Great East Japan Earthquake
Some experts: “Data reliability is low… Exaggerated predictions, no need to worry”
Manual prepared with local governments and companies as the center… Practical preparations such as earthquake experience education
“I’m scared that there might be an earthquake. Can I go to Japan now?”
Mr. K, a Korean food conglomerate employee living in Tokyo, Japan, has been receiving such inquiries from Korean acquaintances almost every day recently. He said that nothing has changed much in his daily life and the Japanese people around him do not care, but he is hesitant about how to respond.
After much thought, he answered, “I’m going about my day as usual, but you can think of Japan as a place where an earthquake can strike at any time.” Most of my acquaintances came to Japan as planned. However, one or two out of ten people sent me messages saying that they postponed or canceled their trips.
On the 8th, a magnitude 7.1 earthquake occurred off the coast of Nichinan, Miyazaki Prefecture, southern Japan. Since then, the Japanese government has announced that the “Nankai Trough Earthquake” has a high probability of occurring, and concerns are growing over whether a giant earthquake will actually occur. There has been much concern in Japan since the announcement of a giant earthquake warning. However, most people are going about their daily lives without much concern. No scientifically proven special earthquake signs or significant tectonic movements have been detected.
Experts advised that we should not be overly anxious about the Nankai Trough Earthquake, but that we should thoroughly prepare for disasters in advance, as the damage could be greater than we can imagine if it were to occur.
● “The probability of a Nankai Trough earthquake occurring has increased”
![Japanese government: “70-80% chance of major earthquake”… Citizens unperturbed by frequent earthquakes[글로벌 포커스]](https://dimg.donga.com/wps/NEWS/IMAGE/2024/08/23/126663880.2.jpg "Japanese government: “70-80% chance of major earthquake”… Citizens unperturbed by frequent earthquakes[글로벌 포커스]")
The Nankai Trough Earthquake is a large-scale earthquake that occurs every 100 to 150 years in the Nankai Trough, which connects the coast of Shizuoka Prefecture, west of the Japanese metropolitan area, through southern Shikoku, and eastern Kyushu.
The Nankai Trough is a huge 4,000m deep trough located at the boundary between the Philippine Sea Plate and the Eurasian Plate under the Philippine Sea in the northeastern Philippines. It is a place where the Philippine Sea Plate has been pushed under the Eurasian Plate and uplifted. The Earth’s surface is made up of about 10 large tectonic plates, and it is believed that the unstable areas where plates meet are more likely to cause large earthquakes and large tsunamis.
There are quite a few earthquakes in Japan’s earthquake history that correspond to the Nankai Trough Earthquake. Representative examples include the 8.0 magnitude Nankai Earthquake that occurred in Wakayama Prefecture near Osaka in 1946 (1,143 dead and missing), and the Ansei Earthquake that occurred east of Tokyo in 1854 (estimated to have killed more than 10,000 people).
The Japanese government predicts that there is a 70-80% chance that the Great Nankai Trough Earthquake will occur within the next 30 years, with a magnitude of 7-8, causing 230,000 deaths and missing persons, and 2.09 million buildings to collapse. Considering that the 2011 Great East Japan Earthquake, which led to the explosion at the Fukushima Daiichi Nuclear Power Plant, left 25,000 deaths (including indirect deaths) and missing persons, one can imagine how much damage this will cause. The logic is that since it has been 78 years since the last Great Nankai Trough Earthquake, it is time to start worrying.
Some point out that this prediction is overly exaggerated. In February of this year, a team led by Professor Manabu Hashimoto of Tokyo Electric University published a paper in the Japanese academic journal Natural Disaster Science, concluding that the probability of “70-80% within 30 years” was “scientifically unsound due to problems with data reliability.” Nevertheless, the Japanese government’s Earthquake Research Committee stated that “there are no plans to reexamine the probability of occurrence.”
An earthquake that is just as worrying in Japan as the Nankai Trough Earthquake is the ‘metropolitan earthquake (an earthquake that occurs directly under the city)’.
In December 2019, the public broadcaster NHK aired the documentary NHK Special “Perceived Earthquake Directly Under the Capital” seven times. The program analyzed Japanese government and academic data and predicted that there was a 70% chance that a magnitude 7.3 earthquake would occur in Tokyo or its vicinity within the next 30 years. The death toll was 23,000, and the economic damage was expected to reach 95 trillion yen (approximately 871 trillion won). The Great Kanto Earthquake (magnitude 7.9) in September 1923, which resulted in the massacre of Koreans, is a representative example of an earthquake directly under the capital.
The 2011 Great East Japan Earthquake, the Noto Peninsula Earthquake in January of this year, and the Miyazaki Prefecture Earthquake this month all occurred in places where people do not live. The Great Hanshin-Awaji Earthquake (magnitude 7.3) that hit the Kobe area in 1995, causing 6,434 deaths, was a major earthquake that was close to an earthquake directly under the capital. The sight of road pillars breaking and overpasses lying sideways is a shocking damage that even Koreans still remember to this day.
The Great East Japan Earthquake did not have a major city as its epicenter. However, the tsunami that hit the Fukushima nuclear power plant, combined with the government’s and Tokyo Electric Power Company’s complacent response, resulted in a radioactive disaster that will be recorded in human history.
● Indifferent reaction to the movement of private property
The Japanese government began to consider the possibility of a major Nankai trough earthquake immediately after the Miyazaki earthquake. The area off the coast of Miyazaki Prefecture where the earthquake occurred is where the Nankai trough connects. As soon as the earthquake occurred, the Japan Meteorological Agency held an evaluation review meeting with experts and concluded that there was a high possibility of a large earthquake.
This is also the background for Prime Minister Fumio Kishida’s decision to abruptly cancel his visit to Central Asia, including Kazakhstan, originally scheduled to start on the 9th, and to stay in Japan to respond to the earthquake. In areas near the Nankai Trough, such as Shikoku, there has been a hoarding of products such as bottled water, canned food, and instant rice, leading to sales at convenience stores and other locations increasing by two to five times the usual amount.
However, in large cities such as Tokyo, the Japanese are generally indifferent. Last year alone, according to the Japan Meteorological Agency, there were 2,227 earthquakes of magnitude 1 or higher (the level at which you can feel a slight shaking) and 41 earthquakes of magnitude 4 or higher (the level at which most people are startled and lights that are hanging on shake violently) – so earthquakes are both a source of fear and an everyday occurrence that is not surprising when they occur at any time. Some people became anxious when posts on social media claimed that low-lying clouds were a precursor to an earthquake, but the Japan Meteorological Agency tried to calm their fears by dismissing it as “baseless talk with no scientific basis.”
According to an internet survey conducted by the University of Tokyo Disaster Information Research Center from the 9th to the 11th, the day after the Miyazaki Prefecture earthquake, targeting 9,400 adults in areas where a large earthquake warning was issued, 83% responded that they were “aware of the warning.” However, 21% said that they “did not take any precautions.”
In Kochi Prefecture’s Kuroshio, where a large earthquake is expected to generate a tsunami of up to 34 meters, 32 shelters were set up throughout the town after a large earthquake warning was issued and “elderly people should evacuate,” but only three people actually evacuated. The next day, 230 people, including elderly people living alone, were called or visited to evacuate, but only eight people evacuated. There are mixed reactions, with some saying that the residents responded calmly in a situation where no unusual signs were detected, and others saying that the response was inadequate when the worst was expected.
Some say that there is no need to worry too much when looking at the analysis and statistical figures that have issued a “megaquake warning” that a Nankai Trough earthquake could occur. Of the 1,437 earthquakes with a magnitude of 7.0 or higher that occurred in Japan over the 110 years from 1904 to 2014, there were 6 cases where a huge earthquake with a magnitude of 8.0 or higher occurred within a week. The 2011 Great East Japan Earthquake was one of them. Since the probability is 6 in 1,437, the Japanese government pointed out that “a huge earthquake can occur once in hundreds of times.” Of course, this figure is several times higher than normal times.
Professor Katsuya Yamori of Kyoto University’s Disaster Prevention Research Institute said in an interview with the Asahi Shimbun, “Until now, awareness of the provisional information (warning of a large earthquake) was low, but this announcement has woken people up from their complacency.”
● Prepare thoroughly with manuals to prepare for disasters
In Japan, disaster preparedness is a daily occurrence due to the fear that an earthquake disaster can occur at any time and any place. Instead of vague worries, disaster preparedness is achieved by familiarizing oneself with a thoroughly prepared manual.
In Japan, when you report your new address after moving, the local government will provide you with a “disaster prevention manual” and disaster preparedness supplies. The 100-page “disaster prevention handbook” provided by Tokyo’s Shinagawa Ward contains detailed action tips and preparations, such as “Protect your head with a pillow or blanket in the bedroom,” “If using an elevator, press all the floor buttons and get off when it stops,” and “Prepare daily necessities for evacuation in case of a power outage.”
In Tokyo, kindergartens, elementary schools, and junior high schools are required to receive mandatory evacuation drills 11 times a year. Employees must receive disaster evacuation and fire drills at their workplaces twice a year. Elementary school students wear folding disaster prevention hats attached to the backs of their chairs at school so that they can immediately reach out and protect their heads when an earthquake occurs.
Tokyo authorities also require businesses to stockpile three days’ worth of food for their employees in case of a disaster. While there is no penalty for failing to comply, most workplaces stockpile long-term supplies such as water, vegetable juice, and dry biscuits in kits to avoid liability issues down the road.
There are also facilities where you can experience earthquakes that you only see on the internet or in the media. The representative example is the disaster experience education facility ‘Sona Area Tokyo’ near Odaiba, Tokyo. You can experience what would happen to Tokyo if an earthquake of magnitude 8.0 occurred directly under the capital and how citizens should prepare through exhibits and experience facilities.
Tokyo = Correspondent Lee Sang-hoon [email protected]
2024-08-24 18:07:16