For Educational and Non-Profit Use Only !

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 !

Tsunami (Shizuoka prefecture)

< About Tsunami >
Chapter2 Tsunami Types (p.1)
1. Long Period
 -- 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 Æ velocity 500km/h
                                                                 water depth 200m Æ velocity 160km/h
                                                                 water depth       10m Æ 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
   (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 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 2nd Wave Break at 1st Wave

Wooden Houses      Partially Destroyed    Completely Destroyed

Stone Houses                  Endurable                Completely Destroyed

Reinforced                                                                      Completely
                              Endurable
Concrete Houses                                                                 Destroyed
Fishing Vessels                          Damage Occurs 50% Damaged    100% Damaged

                   - Slightly Damaged                  - Partially    - Completely Damaged
Tide Water
                   - Block Drifts                        Damaged
Control Forests
                   - Slight Tsunami                    - Block Drifts - No Effect
Fish-Culture
                 Damage Occurs
Rafts
Villages along
                             Damage Occurs          50% Damaged       100% Damaged
Coasts
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. 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

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.