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Gerald Stokes
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1 This flyer was originally created and published in Japanese by Shizuoka Prefecture, Japan. UNESCO IOC ITIC provides this English translation for portions of the original document with the kind permission from the Shizuoka Prefectural Government. (Cover of Original Document) For Educational and Non-Profit Use Only!

2 < About Tsunami > Chapter2 Tsunami Types (p.1) 1. Long Period Tsunami (Shizuoka prefecture) -- Tsunamis caused by the far field earthquakes such as Chilean earthquake in 1960 increase the water level little by little. 2. Short Period -- Tsunamis caused by the near field earthquakes such as Tokai Earthquake sometimes hit in the form of breaking waves. Chapter3 Characteristics of Tsunami Propagation (p.2~3) 1. Tsunami hits repeatedly -- should be cautious at least 12 hours or more. -- not always the first wave is the largest. 2. Speed of Tsunami -- the shallower, the slower Tsunami Velocity (m/s) = (9.8 * water-depth(m)) water depth 2000m velocity 500km/h water depth 200m velocity 160km/h water depth 10m velocity 36km/h -- the speed of tsunami runup onto the land is almost the same as that of human beings running at full speed. (Some could survive by running full speed in case of 1983 Japan Sea Earthquake) 3. Wavelength of Tsunami -- wavelength of tsunami is 10km or so and very long (so cannot feel in the offshore) (vessels are guided to go to the offshore when they have time in case of earthquakes) 4. Period of Tsunami (the period is at most 10 seconds when affected by storm surge) (because of the long period, water inundates widely even trough the slight apertures) (in the past, water even inundated to the land trough water pipes for sewage) 5. Tsunami Height -- tsunami height sharply gets higher when the water depth gets shallower (along the shoaling coasts, tsunami can be in the form of breaking waves) When it gets shallower, tsunami slows down and the following waves overlap to the front.

-- tsunami height sharply gets higher in the V-shaped bays

gets 1m shorter per about 1km inundation) (more damaged when it

3 -- tsunami height sharply gets higher in the V-shaped bays (sometimes waves are oscillated in the bay and amplified) Chapter4 Tsunami Runup (p.4) 1. Runup onto the Lands -- Run-up to the flat lands (tsunami height gets 1m shorter per about 1km inundation) (more damaged when it ebbs away than when it inundates) -- Runup to the cliffs (inundates as far as the tsunami height along the coasts)

2. Runup to the Rivers -- tsunami runs-up quicker than onto the lands so it inundates trough the unexpected places Example of tsunami damage (1993 South-West off Hokkaido Earthquake) Chapter5 Damage

4 2. Runup to the Rivers -- tsunami runs-up quicker than onto the lands so it inundates trough the unexpected places Example of tsunami damage (1993 South-West off Hokkaido Earthquake) Chapter5 Damage to the Buildings (p.5) 1. Wooden Houses -- completely destroyed with inundation height of about 2m -- partially destroyed with inundation height of about 1m (As for the recent constructed houses, second floor is not damaged in many cases while the first floor is damaged and only poles remains) 2. Reinforced Concrete or Iron Frame Buildings -- most parts remain (can be used as the evacuation buildings in case of the sudden disasters)

Tsunami Height (m) Tsunami Shape Tide Swell-up Break after 2 nd Wave Break at 1 st Wave Wooden Houses Stone Houses Partially Destroyed Endurable Completely Destroyed Completely Destroyed Reinforced

5 Tsunami Height (m) Tsunami Shape Tide Swell-up Break after 2 nd Wave Break at 1 st Wave Wooden Houses Stone Houses Partially Destroyed Endurable Completely Destroyed Completely Destroyed Reinforced Concrete Houses Fishing Vessels Endurable Damage Occurs 50% Damaged Completely Destroyed 100% Damaged - Slightly Damaged - Partially - Completely Damaged Tide Water - Block Drifts Damaged Control Forests - Slight Tsunami - Block Drifts - No Effect Fish-Culture Rafts Villages along Coasts Damage Occurs Damage Occurs 50% Damaged 100% Damaged Splash Wave Height (m) Inundation depth (wave height) and scale of disaster (Shuto, 1990)

< Evacuation from Tsunami > Chapter1 Earthquake, Tsunami, Evacuate at once (Slogan) (p.6) 1. When felt a big shake along the coasts, evacuate to a safe, high place etc. at once 2.

6 < Evacuation from Tsunami > Chapter1 Earthquake, Tsunami, Evacuate at once (Slogan) (p.6) 1. When felt a big shake along the coasts, evacuate to a safe, high place etc. at once 2. When Tsunami Advisory or Warning is issued, evacuate to a safe, high place etc. at once 3. When Tokai Earthquake Warning is issued, evacuate to a safe, high place etc. at once Chapter2 Notes for Tsunami Evacuation in case of Sudden Earthquakes (p.6~8) If an earthquake occurred all of a sudden and large tsunami hits, carry out the immediate evacuation thoroughly referring to the following notes. 1. First of all, protect yourself -- If injured, cannot evacuate easily 2. Evacuate to a height first, then evacuate to a higher place (secondary evacuation) -- Sometimes, tsunami happens to show the unexpected features. Don t regard the inundation areas in the past or estimated tsunami prone areas as perfect and prepare for the case to evacuate to the higher and safer places 3. Don t evacuate by cars -- Cars can easily be caught in a jam and get involved in tsunami -- In case of Southwest off Hokkaido Earthquake in 1993, many people tried to evacuate by their cars but were caught in a traffic jam and involved in the tsunami. Example of damage by large tsunami (1993 South-West off Hokkaido Earthquake) 4. Give up preserving or bringing your possessions (property, boat, etc.) -- Many people were involved in tsunami when they went back to their houses to bring their valuables or when they went back to see if their boats were all right -- A few minutes delay often takes lives away

7 5. Daily measures for safety are important such as fixing furniture, arranging passages, etc. -- cannot evacuate if furniture falls at earthquakes or passages are messy -- basic domestic measures for earthquakes are important 6. When tsunami begins to inundate, give up evacuating to the far places, but try to go to as high places as possible that are closer. -- the possibility of falling down by floating debris in water gets higher and it makes it more difficult to evacuate -- sometimes, even tsunami with height of about 50cm takes our lives away due to strong water currents Example of damage by large tsunami (1993 South-West off Hokkaido Earthquake) 7. Evacuate as far as possible from hard stuff (rocks, sea walls, etc.) -- When involved in tsunami, in many cases people are drowned by being flung against hard solid structures like the rocks or concrete and fainted or become injured 8. Evacuate to the second or third buildings from the coasts rather than the first ones in front of the coasts when there is no other way to evacuate to the buildings -- Don t evacuate to the first row of buildings fronting the coasts. If there is no other option, evacuate to the second or third row of buildings from the coasts. # In emergency, there is a limit for an evacuation directive by the administration. # Each local autonomous disaster prevention organization, business establishment and individual should examine tsunami evacuation measures in daily life considering the local tsunami characteristics well.

WHAT IS A TSUNAMI? happens.nz. Long or Strong GET GONE TSUNAMI 101

WHAT IS A TSUNAMI? happens.nz. Long or Strong GET GONE TSUNAMI 101 WHAT IS A TSUNAMI? A tsunami is a series of powerful waves with strong currents. They are mostly caused by underwater or coastal earthquakes, and sometimes by underwater landslides or volcanic eruptions.