1. Tsunami

2. What Is It? Causes Series of traveling shallow water waves
Earthquakes-(most common)
Eruption of coastal and island volcanoes
Submarine landslides
Ocean impacts of large meteorites (rare)
Series of traveling shallow water waves
Hit coast in intervals
Majority of tsunami occur in Pacific Ocean
subduction zones

3. wind generated waves shallow water waves
period seconds
wavelength meters
shallow water waves
ratio between water depth and wavelength is small
period of 10 minutes to 2 hours
wavelength in excess 480 km
2-3 meters high in deep seas

4. In shallow water it loses speed and increases in height
contour of the ocean floor and coast can change speed & direction
Wave height can reach 30 to 50 meters
Rate of energy loss of waves is inversely proportional to its wavelength
Areas most at risk are less than 50 feet above sea level and within a mile of the coast.

5. Recent Tsunamis in Japan

6. 1960 Chile Earthquake Magnitude 9.5
South American plate moved over the subducting Nazca plate
Tsunami hit Chile then reversed 17,000 miles across the Pacific Ocean and hit Japan
water level 4.5 meters
122 fatalities
animation

7. 1993 Hokkaido tsunami Earthquake-magnitude 7.8 in Sea of Japan
misbeleif that a tsunami would not occur in the Sea of Japan
late issue of warning
water levels up to 9 meters
200 fatalities

8. Japan’s management seawalls breakwaters
buoys linked to Global Positioning Systems
forcasting centers work with Tsunami Warning System in the Pacific
conduct drills once a year
some villages move to higher ground
Education
videos
Karakuwa tsunami simulation hall

9. Tips for survival head to higher ground after strong earthquakes
Do not go to the shore to watch a tsunami
cooperate with warnings and evacuation procedures
abandon belongings
realize roads may not be accessible
do not return until the “all clear” is given