The morning, the lighthouse could not be seen.

Transcription

1 Tsunami & Destruction Produced by: Nobuo Shuto The 1946 Aleutian Tsunami Height: 30m The morning, the lighthouse could not be seen. The 18 meter high lighthouse stood on a foundation 10 meters above sea level. Height of the tsunami: 30m 1

2 Spreading over the Pacific Ocean The 1946 Aleutian Tsunami The Pacific Ocean, with an average depth of 4.2 km, is but a shallow puddle for a 100 km wavelength tsunami. And then the tsunami reached Hawaii Although the children recognized that something was wrong and warned the adults, their warning fell on deaf ears. Events of April 1, 1946 (NOAA, NG Data Center) (NOAA, NG Data Center) 2

3 Attempts to flee were too late, resulting in a tragedy. 159 deaths in Hawaii (NOAA, NG Data Center) A worker in Hilo just before being overcome by the tsunami. 3 Basic Configurations of Shallow Water Tsunami Fast Tide The average water level rises and creates tiers. Breaking Bore The original height of the tsunami An offshore tsunami has a first tide Unduar Bore From a water depth of 200 maters to a shallower location Illustration 3-9 Ass the depth grows shallower, a tsunami can assume a variety of shapes. 3

4 Breaking bore Tsunami Configuration The 1946 Aleutian Tsunami The wind and waves decrease after the breaking bore strikes. Lake Jusan during the 1983 Japan Sea Chubu Earthquake Tsunami photo Noriaki Kondo An undular bore developing on the ocean At the head, the wind and waves give rise to other short lived waves. The Oga shore during the Japan sea Chubu Earthquake Tsunami photo Torazo Seki 4

5 An undular Bore Advances up the river The Chilean Tsunami which entered Kitakamigawa (river) caused boats to clash into the Nakai Bridge. Sendai District Weather station 1961 An Undular Bore Developing on the Kitakamigawa (river) 1960 Chilean Tsunami The 2 nd wave The 3 rd wave The 1 st wave (Kahoku Shimpo Co. 5

6 The 2 nd wave A reflected wave from the 1 st wave photo Naotoshi Ohba A Breaking Bore Co-Existent with an Undular Bore The Tokachigawa (river) 2003 Tokachioki Earthquake Tsunami breaking bore undular bore photo token from a Self-Defense Force Army 6

7 Velocity of Tsunami and Tsunami Energy (km/h) Speed of a jet Faster than the Shinkansen (bullet train) velocity water depth 10 1/2 Pacific Ocean Carl Lewis Suruga Bay fast in deep water slow in shallow water (Depth) An Indented Coastline Bending in the Shallow Direction Bent by the geographical features of the shore, the Japan Sea Chubu Earthquake Tsunami concentrated on Minehama Village. (Shuto et al., 1986) 7

8 After being reflected off the coast of the oga Peninsula, the tsunami curved back toward the Shallow shore. The Japan Sea Chubu Earthquake Tsunami was caught by the shoreline due to the indentation of the coast. At least 7 waves struck the Noshiro shore. ( o.470, 1983) 2waves struck at Oga. Shallow Water Effect The shallower the water, the higher The back of the wave reaches land shallow deep The fast rear point of the wave in deep water follows the forward point that reached the shallow end and has slowed. This is the way in the back of the tsunami wave grows. 8

9 The Accumulative Effect The tsunami that entered the wide mouth of the bay is pushed towards the back and grows still higher. Next, it gains strength and runs up to even higher sites. Shirahama Minato Ryori Bay Haruo Matsuo 1933 The tsunami grew higher in the deep part of the by The opposite direction of the tsunami Shirahama at Ryori Bay is a typical example. The Meiji period tsunami ran up to 38 meters, while the Syowa tsunami ran up to 28. The wave was pushed in and grew higher Resonance Effect: Like a Swaying Swing Method of Investigating Tsunami Oscillation The initial water level Drop line The water level immediately after dropping A half-wave is generated Inner bay area Mouth of the bay In long bays, the oscillations are gentle. In short bays, the oscillations are fast. If the tsunami cycles are similar to the characteristics of bay oscillations, the tsunami will grow larger in the inner bay of investigation as a result of the resonance effect. Long bays are a disadvantage for long tsunami distant from land just as short bays are a disadvantage for short tsunami close to land. Water in container will oscillate only a little vibration. The method of in vibration is described to the left. In the top illustration, the support under the right side of the container is suddenly removed. The container falls and the water level slopes as in the middle illustration. The water flows from the higher level toward the lower, as in the bottom illustration, and then sways back and froth. In this container most easily generated waves of half-wide length. Within a bay, the most frequently generated are waves of 1/4 length. 9

10 The tsunami waters met in a mountain pass between Ryori Harbor and Sirahama Depth where water met 38.2 Haruo Matsuo 1933 Ryori Harbor, Iwate prefecture immediately after the Meiji Tsunami Photograph Graphical illustration 10

11 Ryori The Meiji Tsunami Historical Monument Tsunami can come from far across the ocean A tsunami from a distant land the 1960 Chilean Tsunami The Pacific Rim Earthquake Zone Pacific Ocean 11

12 It is believed to the largest-scale tsunami occurring on the Pacific. The characteristics of the 1960 Chilean Tsunami were forward by the earthquake Height of the wave: just under 10 m. Heading toward Japan, the tsunami had a wavelength of 700 km, much longer when compared to tsunami from nearby areas. May the Chilean tsunami that occurred in South America affected the entire Pacific area. Regardless of the direction taken, when you depart from the North pole, you will eventually arrive at the South Pole. The Chilean Tsunami approaching Hawaii Tsunami was generated in Chile, then spread throughout the Pacific, and eventually accumulated on the opposite side of the ocean, Japan The wavelength was a long 700 km. for this reason, despite the distance of 17,000 km, it only took 22 rises and falls to reach the coast of Japan, without any loss of energy. (Oringumi Technical Research Laboratory, Tohoku University Disaster Control Research Center) 12

13 Death toll: 142 persons Victims: 160,000 persons Cost of Damage: 3.5 billion yen (2.2 % of the National Budget) Conditions after 22 hours The tsunami was 5-6 m high from Kamchatka to Okinawa 40 minute to 2- hour cycle The Chilean Tsunami Reaches Japan For the most part, because of the resonance effect, it was a huge disaster for the inner bay of long bays. (Oringumi Technical Research Laboratory, Tohoku University Disaster Control Research Center) Long-cycle tsunami can reappear very well. The calculated measurements of the 1960 Chilean Tsunami (solid line) match the actual measurements (dotted line) very well. Hakodate Water level Aomori Ominato Uda Hachinohe (horizontal axis: Time) 13

14 Tsunami come after a strong earthquake. If you feel a tremor that is so strong you cannot stand up at the beach, go to a place that is more than 20 m high. This rule is only 90% accurate. Even in the case of small tremors, there is a possibility of an extremely large tsunami (tsunami earthquake) A pamphlet from the National Oceanic and Administration regarding tsunami refuge education in the event of tsunami from nearby areas. Earthquake Magnitude & Tsunami Magnitude The Meiji Great Sanriku Tsunami with its 22 thousand fatalities was an earthquake tsunami. The size of a tsunami is Decided by the size of vertical displacement on the ocean floor, resulting from fault movement. A large tsunami earthquake for a rather small earthquake 14

15 Omori (1901) Weak Seismic Intensity The Meiji Great Sanriku Tsunami June 15, 1896 (old calendar May 5) The Tsunami struck around 8 pm. Along the coast, the seismic intensity was under 2. Illustration #119 The Misfortunes of Experience Many experienced people died. Forty-one years ago a tsunami struck but it was only a mild one. Those who stayed on the second storey [of their house] were safe, waiting and coming down only after the sea water receded. Because of this experience, those who did not panic and were not vigilant during the tsunami this time, drowned. On the contrary, may of those panicked, ran away and survived. We should be aware that the size and type of the two tsunami were difficult. Folkways Picture Magazine, 2 nd volume???? Ward Mayor Ando (whose [first] name) was Do [reading?], a person of careful thought and had a great deal of experience. When people were making a big fuss, saying that that a tidal wave was coming, he was smoking quite calmly. He said that tidal wave never come except after a big earthquake, and told the household people not to worry, when suddenly a tsunami came over the house and he died. This happened over 40 years ago, demonstrating that experience can be wrong as far as tsunami are concerned. Iwate Public Gazette, June 30,

16 Unusual Aspects of the Ocean Just Before the Tsunami Hit Many people believe a tsunami begins will a pull, but A tsunami actually begins with a push. The fishing port is calm. Suddenly, the surface of the sea rises. The tsunami overflows the breakwater. Photograph Fumio Sasaki 1983 The Sea of Japan Chubu Earthquake Tsunami at Hatake Fishing Port The 2 nd wave to Oura 9 The 1 st wave of the tsunami rose above the mountain pass Yamada Bay Oura Pacific Ocean Funakoshi Bay The 1 st wave to Oura Oura Koyadori The Keicho Era Tsunami, 1611 The 1 st wave at Oura was a tsunami that rose above the mountain pass. Next, another tsunami came around the peninsula and struck from Yamada Bay to the north. Because of varying geographical features, the location where the tsunami originated and it s the size, it is not sufficient to focus only on the ocean. 16

17 The Sea of Japan Chubu Earthquake A Strange Ocean Roar #1 Nov.4, in a flash, a large of earthquake struck At that time, many who were extremely frightened heard an ocean roar. (Sagara Town, Osawa Temple Documents) A breaking bore over 2.5 m in height produces continuous sound Tsunami in Yonashiro River The storm is getting closer. Many large dump trucks are coming. Photograph Kiyoshi Sato A monument in Aomori A Strange Ocean Roar #2 When layers of waves 5m high and over smash into the cliffs, a loud noise occurs. Distant thunder, blasts, and the artillery guns can be head from far away Of the points within Hirota Bay, sounds could only be head around kurosaki, but since there is no shelter in Kakahama, the sound of the attacking tsunami colliding into the ocean cliffs was heard over and over again. Shuto, 1997) 17

18 The Syowa Great Sanriku Tsunami that Struck after a Severe Earthquake March 3, 1933 The tsunami struck around 3 am. An intensity distribution map of the Syowa Sanriku Earthquake (Meteorological Administration, 1983) X marks the epicenter On the Sanriku coast, it was intensity 5. Ryori Shirahama immediately after the Showa Sanriku Tsunami Where the waters met Port of Ryori Ryori Shirahama Because it was 10m smaller that the Meiji Tsunami, the tsunami waters did not meet at the Port of Ryori. A tree 30 cm in diameter was bent over and broken. 1 18

19 Results of Trace Investigation The Syowa Sanriku Tsunami at Kuwagasaki, Miyako Bay Anyone might expect it to be 3-4 meters, but It actually was 7-8 maters. 1 9 Details of the Syowa Sanriku Tsunami at Miyako, Kuwagasaki It s not unusual to have a difference of 3 m in height at a distance of 100 m. As a result of the collision of seawater running with great force, this sort of difference can develop. 7.2m 6.1m 4.5m 4.0m 500m Ministry of the interior, Sendai Public Works Branch Office, Miyako Bay repairs Office Inverstigation (Public Works Experimentation Laboratory Report #24, 1933)

20 1933 Tsunami trace Figures from within Okushiri Port At a distance of 50 m there is a difference of 2m. 4.0m 2.0m 3.4m 2.1m 3.7m 5.7m Hokkaido Earthquake Measures Investigation Committee Data 1995 Water level rises as structures collide in the intense velocity of the current. Differences with the part of water passing through roads give rise to new waves. Waves are generated by collisions. 4 minutes 35 seconds after the earthquake occurred (Produced by Unique) 20

21 At the same location, the map to the left shows5.1 m,and to right, 7.8 m Measurements of the Syowa Tsunami at Ofunato Bay Tokyo University Earthquake Research Laboratory Because such things can occur, careful precision is needed Department of the Interior, Engineering Works Research Institute Types of Tsunami Disasters Based on Past Experience Loss of life Destroyed homes caused by tsunami & floating objects Destroyed disaster damage from scouring, displacement prevention structures Traffic obstruction railways, road, ports Lifeline damage sewers waterworks, electric power, communication, Damage to marine aqua-cultural rafts, fishing boats products industry Damage of commerce value of goods falls due to flooding and industry Damage of the agricultural industry products, cultivable land, irrigation ditches Damage to forests physical, biological damage Fires source of fire: kitchen fire, short circuits, etc. Oil spills cause fire to spread, environmental pollution Geographical change changes in sandbars, shoals, sandy beaches, etc. Nobuo Shuto,

22 Tsunami Strength and Form, degree of Damage Tsunami strength Tsunami height (m) Tsunami Form sounds Aqua-cultural rafts Easy slope Steep slope Wooden house construction Stone house construction Steel, concrete building Fishing boat Damage to protected lakes, forests Result of protected lakes, forests Inundated costal communities Height achieved 1 Builds up at the coast Fast tide Partial destruction Damage occurs Slight damage Reduction of tsunami Drifting objects prevented Damage occurs 2 Endures the attack Endures the attack Wall of water at the coast. Damage of 2 nd wave fast Total destruction Damage occurs 4 Damaged object increase at the point Continuous noise from the damage in front (ocean roar, violent wind, thunder) Drifting object prevented 50% rate of damage Loud noises at the beach from the damaging rolling waves (thunder, not recognized at a great distant) (no documentation) Partial damage At the coast, loud crashing noises (thunder, and crashing heard from far away) (no documentation) 50% rate of damage Total destruction 100% rate of damage Overall damage No results 100% rate of damage Even in the 1st wave, damage from rolling wave occurs Total destruction Nobuo shuto, 1992, 1993 Human Damage The tsunami occurred on June 15,1896. It was the Boys Festival in the old calendar, about 8 O clock in the evening Typical tsunami earthquake Evacuation precautions taken - none Deaths (persons) Hokkaido Aomori Iwate Miyagi ,154 3,

23 No efforts ware made to evacuate during the Meiji Sanriku Tsunami. The number of homes washed away was proportionate to the number of deaths The Meiji Great Sanriku Tsunami The Syowa Great Sanriku Tsunami Number of death Number of death Numbers of homes washed away Numbers of homes washed away Nobuo Shuto 1987 The Disposition of the Dead At kamaishi, there were not enough Straw Mates As for Hirota, there were too many dead to gather at once. It was necessary to make two attempts to gather them. Storm Illustration 23

24 Percentage of deaths Meiji Sanriku Syowa Sanriku Tonankai Hokkaido Nanseioki Nankai Percentage of deaths upper limit Lower limit of death percentage The best and only way to save lives to early evacuation. The death rate for tsunami of the same height can differ by 3 figures. Early evacuation results in this difference. Tsunami height (m) Tsunami height and death probability 1997 Can you take refuge while watching a tsunami? The 1960 Chilean Tsunami: Photo of Onagawa Town, Miyagi Prefecture. With the Tsunami already at their feet, people are watching it while making their getaway. National Geographic Institute,

25 Observers who Narrowly Escaped 1968 Tokachioki Earthquake Tsunami In front of the Kamaishi Fish Market People came to see the seldom seen ocean floor. Transportation Ministry Ports and Harbors Bureau, 1968 They barely escaped from the 4 th wave that followed. Overtaken Even by a Small Tsunami 1983 Sea of Japan Chubu Earthquake Tsunami, Jusanko, Iwaki River Estuary 9people running strenuously And then no one was left. Depth of water: 70 cm Photograph Noriaki Nara 1 person (left, engulfed by a wave) 25

26 Examples of the Sick and Wounded Meiji Great Sanriku Tsunami Miyagi Prefecture Case Symptoms of 1,329 hospitalized patients and [number of death] Bruised 292 [6] Sprains Respiratory diseases Digestive diseases Neurological / sensory diseases [8] [13] [1] Abrasions Lacerations Bone injuries [1] [3] [3] Special record was made that noting could be done for those patients suffering from decorative pneumonia Sea of Japan Chubu Earthquake Tsunami Actual Results at Nosiro locate No. percent during tsunami No. percent into the ocean Deaths Injured Total death Object on ocean (Note 1) (100) 24 (45) 24 (45) 48 (91) Vessels (Note) (Note 1) At the coast (Note 2) Immedia tely after the coast (Note 3) After leaving coast No. on small boat No. on large ships No. on small boat No. on large ships No. on small boat No. on large ships (89) ( 3) (28) (-) (17) (-) (9) (5) (10) 1. Those on vessels on the ocean away from the coast 2. Those on vessels at, just departing from, or 100 m or more from coast 3. ( ) percentage of 4. Values have been finalized for this investigation (-) (3) (-) (43) (25) (10) (20) (17) () (51) (30) (21) (20) (21) (0) 13 out of 15 overturned 1 out of 9 overturned 3 out of 11 overturned 1 ship, none overturned 2 out of 12 overturned 12 ships, none overturned Sea of Japan Chubu Earthquake Overall Investigation Report, National Land Agency,

27 Kamaishi after the Meiji great Sanriku Tsunami Large volume of sand brought in by the tsunami A photograph sold at the time Property of the Sendai City Museum Gusting Wind Just Before the Tsunami Struck Gusting Wind Justas the wave came, our hands were thrown up and then we were twisted around and thrown down. It was the same before the wave hit the warehouses and homes; they were twisted and thrown down, offering no hindrance to the wave. Homes and warehouses all collapsed from the air pressure, move violet then a cannon. Report of the Meiji Great Sanriku Tsunami by Otsu Town, Iwate Prefecture Article from the Iwate Newsletter June 24,

28 Deeds of the Wind the Case of a Certain House in 1993 Hokkaido Southwest Coast Earthquake Tsunami Path of the tsunami On the south side of the road, the tsunami hit the entire area. On the North side of the road, the walls of the houses were blown off by the strong wind Degree of destruction moderate Photograph Nobuo Syuto 25 cm of flooding on the first floor Destruction of Homes Total destruction beams and entire building destroyed Major destruction most of the walls and beams destroyed Moderate destruction beams remain. Some walls destroyed Minor destructions windows are broken but walls remain Flooding only no mechanical damage Some damage Little damage Photograph Nobuo Shuto 28

29 Yardstick for Estimating Damage to houses of Wood Construction Flood water 1 m deep - partial destruction Flood water 2 m deep - total destruction Initial conditions of destruction Current velocity:4 m/s Hideo Matsutomo, Nobuo Shuto, 1994 Moderate damage Severe damage Photograph Nobuo Shuto Drifting objects are more frightening than the water Not released by copyright protection Yomiuri Newspaper Shizugawa Town during the Chilean Tsunami A large Ship Beached at Ofunato Sakaicho Town during the Chilean Tsunami Asahi newspapers 29

30 Depth of water Approaching the mountain and overflowing the dike, in a very short time, seawater filled the area behind the dike. Next, overflowing water left the back and rear quarters scoured Destruction of a Dike Due to the water overflow the back and rear quarters scoured Washed away dike Not damaged Nobuo Shuto, 1999 Height of dike 1960 Funakoshi, Iwate Prefecture Chilean Tsunami joint Investigation Summary, 1961 Destruction of Wharfs, etc Receding waters of the ebb tide expose the from quarter and beating against it, cause scouring. Receding waters of the ebb tide, Hakodate 1960 Chilean Tsunami Joint Investigation Summary,

31 Scouring, as a result of water flow, is the primary cause of destruction The 2 nd fish market of Konakano, Hachinohe Port during the 1960 Chilean tsunami. The entire fish market was inundated. Hachinohe Port Engineering Office, 1961 The speed of the current at the entrance of the shipping port was 13 m/s at ebb tide (max.), 8 m/s at high tide (max.) The wharf at the Konakano fish market was previously constructed at (-)3m, But after scouring, upending, sinking and submerging, was (-)9m. Gradually collapsing the Konakado 2 nd Fish Market Wharf Hachinohe Port Engineering Office,

32 Where water accumulates, protective construction is needed. The Makiya Ohashi (bridge), Okinawa after the 1960 Chilean Tsunami Taneichi Rikukan after the 1933 Showa Sanriku Tsunami Quarterly Journal of Seismology, 1933 National Meteorological Agency Technical Report, 1960 Large-Scale Geographic Change 1961 The 1960 Chilean Tsunami cut through kiritappu, Hamanaka Town, Hokkaido. Keiichiro Yamaguchi, Measurement,

33 An 8 meter high hill produced by a tsunami Everything above the red line is accumulated sand. (From the tsunami of Ansei) The entrance to Minami Izu Town Aquaculture Rafts No.1 Matoya Bay, Mie Prefecture Normally, the cultured pearl rafts are lined up in this way. No.2 The Cultured pearl industry of Kiinagashima district was destroyed. Many people are working on the rafts. (National Meteorological Agency, 35 Technical Report, 1970) Damage to rafts begins from a current velocity of 1 m/s. (1) Moving rafts no damage (2) Rafts that drifted away percent of shells dropped 10% Rafts repairable (1 m/s) (3) Rafts that collided, in disarray percent of shells dropped 20-20% Rafts repairable (>4 m/s) (4) Rafts piled on top of each other percent of shells dropped 70-80% Rafts not repairable (>10 m/s) (5) Rafts drifted out to open sea/sunk percentage of rafts/shells lost 100%

34 Percentage of Damaged Fishing Boats 1960 Chilean Tsunami Hachinohe Niidagawa Port Wharf Tsunami Height 3.3m Of approx. 400 boats, 90% ware swept out to sea. Actual results of the 1983 Sea of Japan Chubu Earthquake Tsunami Small boat Large ship National Meteorological Agency Technical Report, #8, 1970 Nobuo shuto 1992) The 1968 Tokachioki Earthquake Tsunami Noda Fishing Port, Iwate Prefecture When stranded by a surging wave, the backwash that follows is dangerous. It is dangerous to send boats out to the open sea for safety. Transportation Ministry, Ports and Harbors Bureau,

35 A large whirlpool formed at Hachinohe port during the 1968 Tokachioki Tsunami Tsunami and Fires During the Showa Great Sanriku Tsunami 3 fires ware recorded. At Kamaishi, when the 3th wave struck, Fires broke out. Could short circuits have been the cause? Not released by copyright protection Asahi Newspaper Co. 35

36 During the tsunami, fires could not be extinguished. Approximately 200 sites ware burned. Kamaishi Town Earthquake Disaster Damage Illustration. Washed away Flooded Burned down Haruyoshi Ogaki, 1933 Tsunami, Fires and Combustible materials Up to new, there are 5 examples of the most horrific secondary disasters. An estimate of the area burned by petroleum A(m 2 ) A =325V V(kilolitre) is the volume Shuto,1991) ofiol reserves. Whittier, Alaska,

37 The case of the 1964 Niigata Earthquake Burned area Area where the tsunami and ground water collected Fire Prevention Agency, Niigata Earthquake Report, 1964 Legend Mo/Da Time Recorded time of burned area Direction the fire spread Flooded area First fires which broke out immediately after the earthquake Fire Prevention Agency, Niigata Earthquake Report, 1964 Condition of the fires in the afternoon on the day they broke out (June 16) During the earthquake, oil overflowed from the tanks and was nearly entirely consumed in flames. 37

38 The Yamanoshita district covered in oil from a group of 100 tanks of sea of fuel oil. Niigata Nippo News 5 hours after the earthquake, a second fire broke out The 2th fire 39 Afternoon fire conditions on the day of the fire (June 16th) All was burned by the flames from the crude oil around the Shoseki tanks. The building in the center is the Tohoku Electric and Heating Power Plant. The smoke on the right is from the Narusawa Oil tank fire. The 2th fire has not yet broken out. 38

39 About 300 sites ware burned. Niigata Nippo News Earthquake & Tsunami and the Destruction of Tanks Earthquake Research laboratory, 1946 (The Great Alaska Earthquake of 1964, NAS, 1972) During the Tonankai Earthquake, fuel oil tanks On Jinki Island ware washed away, But since they ware empty, disaster was avoided. 39

40 Tsunami can strike anywhere along the Japan coast. During this period, the worst recorded strike was at Miyako Island. Accumulated energy values of Tsunami strikes since 1600 Hokkaido Hokkaido Aomori Akita Yamagata Niigata Toyama Ishikawa Fukui Kyoto Hyogo Tottori Shimane Mie Aomori Miyagi Iwate Ibaraki Fukushima Chiba Tokyo Kanagawa Shizuoka Hyogo Aichi Osaka Tokushima Ehime Oita Miyazaki Kagoshima Wakayama Kochi Soda, 1988 Every Tsunami is unique. Disasters are evolving. 40