The 1983 Sea of Japan earthquake, also known as the 1983 Nihonkai-Chubu earthquake, occurred on May 26． It was 7.8 magnitude and occurred in the Sea of Japan. The tsunami caused 104 deaths, 100 caused by the quake. The tsunami hit communities along the coast, primarily in Aomori and Akita Prefectures and the east coast of Noto Peninsula.
There are three things to share about the tsunami disaster.
The first is the tsunami-generated location, the second is the broadcasting, and the third is the victims of school children. First, there was an ancient tradition that tsunamis never hit the coast of the Sea of Japan. This normalcy bias* exacerbates the damage. The second was the first tsunami disaster broadcast worldwide during that time. The people who had home videos also contributed to the media. The tsunami warning system, which provides wireless tsunami information from the Sea of Japan to the local area to inform local people, was improved after the event. Third, 43 schoolchildren were hit, and 13 passed away. They were on an excursion. The school teacher could not do anything during that time. The 2011 Great East Japan Earthquake and Tsunami disaster also had teacher-related issues. Both tsunamis were daytime.
After the Indian Ocean Tsunami in 2004, we started collecting information on the tide gauge records around the Indian Ocean. In 2008, we also discussed the emergency management aspects for future possible tsunamis in the Indian Ocean at Pacific Tsunami Warning Center (PTWC)*, International Tsunami Information Center**(ITIC), and Univ. of Hawaii Sea Level Center(UHSLC)***.
*Pacific Tsunami Warning Center
We can confirm the present tsunami warning information.
The PTWC is the world’s core center for tsunami warnings.
As you may know, the tsunami is a Japanese word. The name comes from the Hiro village (many Japanese settlers lived there) in Hawaii, severely affected by the tsunami in 1968. The villagers called the wave “Tsunami.”
**International Tsunami Information Center
They have important historical tide gauge records.
***University of Hawaii Sea Level Center http://uhslc.soest.hawaii.edu/
We can confirm the sea level is rising around the globe.
Extra……..(^^)
The famous Hitachi company’s symbol image tree in Hawaii was found.
I will update a column of the NIED e-mail magazine I wrote long ago because the content does not fade with time. (I will do this step by step in Japanese and English.) I will also add comments to update the situation.
Sorry, I am now revising this post because of the translation difficulties. This post will be revised again. Thank you.
Published May 6, 2010 NIED-DIL e-mail magazine: Disaster Warning (1)
■ Disaster Warning (1) ■
In February 2008, a survey provided an opportunity to visit Hawaii’s Pacific Tsunami Warning Center (PTWC). In a study, I interviewed the director of the PTWC, and the first thing that caught my attention was the role of the media. The director told me that a public tsunami evacuation alert was required three hours before the event, which was too time-sensitive, but the press was an advantage to do this. However, there were various restrictions for the government organization, such as warnings in an international framework. I remembered the Chilean Navy’s disaster response to the damage caused by the earthquake and tsunami in Chile in February this year.
Next, I was interested in science, technology, and data, which are the basis of alarm decisions. I think regular (flood, etc.) warnings will be judged based on current and past data, but especially for tsunami warnings, there were errors in the original earthquake and the tide gauge data. To judge, we should know that 99.99 percent of the errors could be caused by error. The fact that past data is not very useful because the devices to figure out the data are changing daily, making it difficult to rely on it.
From these facts, it was generally noticed that the disaster warning was based on the combination of the progress of science and technology and the competence of the person in charge. The actual warning also relies on the institution belonging to it. For example, variables such as the recipient of the alert, the psychology of the local people, the social situation, and various systems also needed to be added.
80% ofall tsunamis occurring in the world are concentrated in the Circum-Pacific Belt.The leading countries researching the tsunami are Japan, the U.S., and Russia. The tsunami is originally a Japanese term that means a high tidal wave. The name was used by Japanese immigrants during a tidal wave caused by the 1946 Aleutian Islands earthquake (tsunami) hit in Hiro, Hawaii and it became an international word, especially an academic word, ”Tsunami”. The International Union of Geodesy and Geophysics (IUGG) is in charge of a tsunami session at the start of an international conference about tsunamis. “Tsunami” became public after the 2004 Indian Ocean Tsunami disaster.
*The word “tsunami” is composed of the Japanese words “Tsu” (which means harbor) and “Nami” (which means “wave”)(ITIC)
On the early morning of May 23, 1960, a massive earthquake, the largest ever recorded with a magnitude of 9.5, struck southern Chile. This earthquake unleashed a tsunami that swiftly crossed the Pacific Ocean, reaching the Japanese coast about 22.5 hours later. The tsunami, which surged up to 8 meters high, resulted in 139 deaths and caused the destruction or displacement of 2,830 buildings across Japan. Due to the geographical position of Chile opposite Japan, the tsunami’s impact was more pronounced upon reaching the Japanese shores. These distant tsunamis are particularly challenging to forecast since they occur without the preliminary tremors typically associated with earthquakes. Consequently, regions prone to seismic activity, particularly around the Pacific, including Hawaii, have established early warning systems.
In 2004, the Indian Ocean was struck by another significant earthquake, which triggered a devastating tsunami. At that time, the absence of a tsunami warning system in the Indian Ocean contributed to a staggering death toll of 300,000. The effectiveness of tsunami warnings is limited by their ability to reach extensive coastal areas promptly. Therefore, it is crucial for residents to be aware of their local environmental characteristics and rely on personal judgment and preparedness to mitigate the risks posed by tsunamis.
Large tsunamis are caused by significant earthquakes of magnitude eight or greater. In particular, such earthquakes frequently occur along the Pacific coast of Hokkaido and Tohoku in Japan. The Sanriku coast in this region has a unique shape called a “rias coast,” which is prone to tsunamis. In the 1896 Meiji Sanriku tsunami, the tsunami reached a height of 38 meters and killed about 22,000 people. Thirty-seven years later, in 1933, another major tsunami, the Showa Sanriku tsunami, struck the region, killing approximately 3,000 people. 2011’s Great East Japan Earthquake and Tsunami did not fully apply the lessons of the past, leaving approximately 18,000 people dead or missing.
The time between an earthquake and a tsunami reaching the coast is very short, from 5 to 10 minutes. Running to higher ground quickly is almost the only way to protect yourself from a tsunami. The tsunami will reach the coast where it is the highest and also get to the coast the fastest. Therefore, instead of waiting for information from the outside, it is essential to have knowledge about tsunamis, understand your surroundings, and act on your judgment.
When a large earthquake occurs at the bottom of the ocean, the ground suddenly lifts and sinks. This movement directly affects the surface of the ocean, creating large waves that spread far and wide. This is the typical way an earthquake-induced tsunami starts. Smaller earthquakes do not cause tsunamis because the shape of the ocean floor does not change much. Also, if an earthquake occurs very deep in the ocean, tsunamis do not occur because their effects do not reach the surface of the ocean. Large tsunamis are caused by huge earthquakes in deep ocean trenches, which are caused by the subduction of the Earth’s plates. In this type of earthquake, the ocean surface is pushed up or pulled down. On the side where the ocean is pushed up, the waves rise; on the side where it is pulled down, the ocean lowers. Which of the two is the first wave of a tsunami has a lot to do with how you perceive the danger and how you escape; the nature of the tsunami that hit Sumatra in 2004 (magnitude 9.0) caused the southern part of Thailand to be hit by a wave that pulled the ocean down, and the nature of this tsunami increased the damage.
The Great East Japan Earthquake and Tsunami (GEJET) disaster is the deadliest disaster after the Second World War in Japan. The earthquake happened at 2:46 p.m. on March 11th, 2011. The total casualty number is 19,846 based on the EM-DAT. The maximum . tsunami height is 40m on the Sanriku Ria Coast. The first wave arrives approximately 30 minutes after the earthquake.
The Sanriku areas have a special geographical condition mentioned as the Sanriku Ria Coast. The coast has mountains close to the sea, so residential areas are limited only in the narrow and lower zones near the sea, and the areas become very vulnerable against the tsunamis. The bays on the coast are small, and the sea inside the bays is very deep. This makes tsunamis faster and higher, which is why the Sanriku Ria Coast has the highest tsunami risk area in the world.
Because of these characteristics, the communities on the Sanriku Ria coast, mainly in Iwate prefecture, have historically been severely affected by tsunami disasters such as the Meiji Sanriku Tsunami (1896), Sowa Sanriku Tsunami (1933), and Chilean Earthquake Tsunami (1960), compared to the flat coast mainly in Miyagi prefecture and other areas in Japan.
I will explain a little bit about the Meiji (1896). This disaster is so-called a surprise attack. The tsunami disaster happened at approximately . 7:30 p.m. on June 15, 1896, mainly on the Sanriku Ria coast. The dead and missing number has been reported at over 22,000. The earthquake is not so strong (the Japanese earthquake scale indicates Shindo 1-2); however, the tsunami is very strong and high (the maximum height is 38.2m in the Ayasato area (present-day Ofunato city)) compared to the earthquake movement scale. This has severe impacts.We call this huge tsunami caused by a weak earthquake Tsunami Earthquake. The first wave arrives approximately 35 meters after the earthquake. The Meiji (1896) has been the worst tsunami disaster ever in Japan.
In 1611, the larger tsunami (Keicho Sanriku Tsunami*) than Meiji hit the Sanriku area. That could also be a “tsunami earthquake.” After that, every 40 years, the people in the area tended to have a big tsunami. Even though they had such experiences, they did not have good tsunami disaster countermeasures, and the tsunami was a “tsunami earthquake.” In addition, they had some ancient traditions, like the idea that a tsunami was a punishment from the gods and Buddha. These are the main causes that made the Meiji worse.
Earthquakes, being a natural phenomena, have generated both attraction and fear among people worldwide. We are aware of earthquakes leading to enormous devastation, fatalities, property damage, and potentially initiating tsunamis. Despite the numerous technological developments, earthquakes remain unpredictable and have the potential to occur at any given moment and location.
An earthquake is the result of a sudden slip between two blocks of the earth’s crust, which leads to the release of energy in the form of seismic waves. Seismic waves propagate through the Earth’s crust and can be monitored by devices known as seismometers. Earthquakes occur in various regions of the planet, encompassing terrestrial areas, subaquatic environments, and even within the earth’s mantle. The seismic intensity of an earthquake is quantified using the Richter scale, which spans from 1 to 10.
Earthquakes result from a multitude of sources, encompassing tectonic plate displacement, volcanic eruptions, and even anthropogenic operations like mining and drilling.
Natural calamities arise from a combination of intricate and diverse factors, resulting in many consequences. They are frequently impacted by numerous factors, including as geographical location, climate, and human activities. Deforestation can exacerbate flooding by diminishing the soil’s capacity to absorb water. Climate change is exacerbating the intensity and recurrence of weather-related catastrophes.
The impacts of these calamities are similarly varied. Natural disasters can lead to fatalities, property damage, population displacement, infrastructure devastation, and economic decline. Additionally, they have the potential to induce enduring ecological harm, such as the degradation of soil and the depletion of habitats, which may take several decades to restore.
Analysis of a Particular The circumstances: The most devastating natural disasters worldwide
Throughout history, the global community has observed a series of profoundly catastrophic natural calamities. The 2004 Indian Ocean earthquake and tsunami was a catastrophic event that resulted in a significant loss of human life. It caused the death of more than 230,000 individuals in 14 different nations, making it one of the deadliest disasters in recorded history. The occurrence also resulted in extensive devastation, leading to the displacement of millions of individuals and the severe destruction of numerous coastal communities.
Likewise, the earthquake that occurred in Haiti in 2010 resulted in the death of over 230,000 individuals and left 1.5 million people without a house. Additionally, it resulted in significant harm to the country’s infrastructure, severely impacting its economy and posing a formidable challenge for recovery.
