Japan: historical suffering from earthquakes and tsunamis
Japan lies at the junction of major tectonic plates, and thus sits on top of an area prone to earthquakes and volcanoes. The Eurasian Plate, Philippine Sea Plate, North American Plate and the Pacific Plate all collide and are in a constant state of stress along the Japan's east coast. Subduction zones where these plates meet eventually build up enough pressure to release and the result is an earthquake and sometimes a tsunami.
The northern Japanese island of Hokkaido is nestled up against the Kuril-Kamchatka trench, a place where the Pacific tectonic plate dives beneath the Eurasian plate, and home to terrible earthquakes in excess of magnitude 8.0 sometimes combined with Tsunamis.
The word "tsunami" is originally a Japanese word, but today it's commonly used in English. And it's been all over the news since a powerful earthquake sent a wall of water into northeastern Japan on March 11. It is fitting that the global word for this natural disaster is the word the Japanese people use: Tsunamis happen frequently in Japan. Almost one-third of all recorded large tsunamis happened in that country. The first English use of the word happened more than 100 years ago. That's when an earthquake struck off the east coast of Japan, very close to where the recent tsunami hit.
The words "tsu-nami" in Japanese means "wave in the harbour", the name derives from the experience of fishermen that only when they returned from the sea into the supposed secure harbour they discovered the terrible destruction that these waves can cause on the shore. Tsunamis are generated by the rapid dislocation of large quantities of water by displacement of the seafloor triggered by earthquakes or landslides, also by explosions caused by volcanic eruption or meteoric impacts. The Pacific Ocean is surrounded by tectonic active borders of the lithospheric plates; nearly 53% of tsunamis worldwide occur here and 82% of them are caused by earthquakes.
Recently Japan was hit by an enormous earthquake on March 11, 2011, that triggered a deadly 23-foot tsunami in the country's north. The giant waves deluged cities and rural areas alike, sweeping away cars, homes, buildings, a train, and boats, leaving a path of death and devastation in its wake. Video footage showed cars racing away from surging waves. The United States Geological Survey reported the earthquake and on Monday revised its magnitude from 8.9 to 9.0, which is the largest in Japan's history. The earthquake struck about 230 miles northeast of Tokyo. The Pacific Tsunami Warning Center issued warnings for Russia, Taiwan, Hawaii, Indonesia, the Marshall Islands, Papua New Guinea, Australia, and the west coasts the U.S., Mexico, Central America, and South America. As of June, tens of thousands of people were still in temporary shelters and over 24,000 were confirmed dead or missing.
The Japan Meteorological Society has, at the time, forecast more major tsunamis in the area, with some expected to reach more than 30 feet (10 m) off the coast of Hokkaido, Japan's second largest island. A tsunami was also generated off the coast of Hawaii, one that could cause damage along the coastlines of all islands in the state of Hawaii, according to the Pacific Tsunami Warning Center. Tsunami warnings are in effect across Hawaii as well.
Over the centuries, Japan has been the land most plagued by tsunamis, with at least 66,000 deaths recorded there since A.D. 684. Among the deadliest tsunamis was one that struck Honshu, Japan, in 1896, killing an estimated 27,000.
In 1596 an earthquake offshore reportedly generated a tsunami that destroyed the island of Uryu-Jima completely and caused more than 4.000 deaths. An official diary about the life and work of the Japanese warlord Tokugawa Ieyasu in his residence city of Sumpu from 1612 contains what is probably the earliest example of the written word of "tsu-nami". The text contains eyewitness-reports of a tsunami that hit north-eastern Honshu, killing thousands of people on December 2. 1611.
On 26. January 1700 contemporary chronicles describe a surprising tsunami, which caused minor havoc, but was not preceded by an earthquake (that earthquakes can be followed by a tsunami was already a well known fact). Research 300 years later revealed that this "orphan tsunami" was generated by an estimated magnitude 9 earthquake offshore the North American coast.
One of the many tsunamis in Japan's history, the Oct. 28, 1707, disaster was triggered by an 8.6-magnitude earthquake and has been studied in connection to the subsequent Fuji Volcano eruptions. It had a Death toll of 30,000.
Possibly one of the largest tsunamis recorded in the history of Japan followed a strong earthquake in 1737. Information is scarce and written records are based mostly on rumours: according to these a 64meter (!) high wave devastated the island of Yezo (modern Hokkaido) and destroyed the coastal city of Kamaishi, thousands of people died.
On June 15. 1896 many villages along the coast of Sanriku were celebrating the return of the soldiers from the war against China, when an earthquake of magnitude 8.5 occurred nearly 145 kilometres offshore of Honshu. The direct effects of the five minutes long quake were of minor entity, the epicentre was distant enough to reduce catastrophic movements on the main island and earthquakes were nothing unusual in this region. However 35 minutes after the earthquake the most devastating tsunami experienced until then in modern Japan hit the coast, one of the subsequent waves reached a height of over 30-38 meters. 26.000-27.122 people were killed and 9.000 buildings destroyed, the effects of the Tsunami were observed over the entire Pacific, in Hawaii some houses were swept away and a three meter high wave reached the coast of California.
The tsunami of the Great Tokyo Earthquake occurred on the 1 September 1923. The devastation of the earthquake was caused mainly by the subsequent fire, but it triggered also a 11m high wave - estimated 90.000-130.000 people were killed.
In 1933 another very strong tsunami hit the coast of Sanriku. The earthquake of magnitude 8.4 occurred on March 3. 1933, this time also the quake caused heavy damage and landslides, it was then followed by a 21m high tsunami; In sum more than 6.000 people died.
In the years after the tsunami of 1896 authorities had invested in catastrophe mitigation, escape routes were build and the coast reinforced by special constructions (4m high walls and artificial barriers) and planted trees. Most effort was put into education; booklets warned of the consequences of earthquakes in the sea and explained the signs of danger of a incoming tsunami: a tsunami can be preceded by a loud noise like a thunder, the most important warning sign is however the temporally retreat of the sea before the first wave.
In May 1960 a tsunami generated by an earthquake off the coast of Chile reached the coastline of Hokkaido, causing havoc on the island of Okushiri, 142 people were killed.
Okushiri was hit again in more recent years. July 12. 1993 an earthquake of magnitude 7.8 caused an 6-10m high tsunami that hit the small island to the west of Hokkaido (in nearly the same region an earthquake on August 29. 1741 produced a tsunami with a maximum run-up of 90m along the adiacent coast). From 680 buildings in the city of Aonae 550 were destroyed or damaged, more than 200 people were killed.
List of the deadliest tsunamis in Japan's history with date/year, affected region and estimated death toll.
27.05.1293- Sagami Bay 23.024
20.09.1498- Nankaido 26.000
List of the deadliest tsunamis in Japan's history with date/year, affected region and estimated death toll.
27.05.1293- Sagami Bay 23.024
20.09.1498- Nankaido 26.000
31.01.1605- Nankaido 5.000
06.01.1700 Cascadia Earthquake 31.12.1703- Tokaido-Kashima 5.233-6.000
28.10.1707- Tokaido-Nankaido 30.000
24.04.1771- Ryukyu 13.486
21.05.1792- Southwest Kyushu 14.500-15.030
1826- Not specified 27.000
15.06.1896- Sanriku, 20.000-26.00001.09.1923
28.10.1707- Tokaido-Nankaido 30.000
24.04.1771- Ryukyu 13.486
21.05.1792- Southwest Kyushu 14.500-15.030
1826- Not specified 27.000
15.06.1896- Sanriku, 20.000-26.00001.09.1923
02.03.1933- Sanriku 3.000-6.000
20.12.1946- To-Nankai 1.330
07.12.1944- To-Nankai 1.223
20.12.1946- To-Nankai 1.330
07.12.1944- To-Nankai 1.223
04.03.1952
26.05.1983
12.07.1993
Sources:
26.05.1983
12.07.1993
Sources:
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