1. Tsunami Series of very long-wavelength waves on the ocean

3. Tsunami = "tidal wave" = "tidal wave" Tsunami has nothing to do with tides Tsunami has nothing to do with tides

4. Video clip: Tsunamis

5. Tsunami waves Very small out in the open ocean Very small out in the open ocean Amplitude of only ~ 1 meter Amplitude of only ~ 1 meter Very long wavelengths (up to 100 km) Very long wavelengths (up to 100 km) Travel very fast (as much as 500 mph) Travel very fast (as much as 500 mph)

7. Tsunami waves When waves reach shallow water, they "feel" the shallow bottom, just like ordinary waves, and they slow down (to 20-30 mph) When waves reach shallow water, they "feel" the shallow bottom, just like ordinary waves, and they slow down (to 20-30 mph) Because of the massive energy, this slowdown causes them to build up very high (up to 50-100 m) Because of the massive energy, this slowdown causes them to build up very high (up to 50-100 m)

9. Tsunami can be generated by any process that displaces a large amount of water: Sub-sea earthquakes Sub-sea earthquakes Giant landslides Giant landslides Volcanic eruptions Volcanic eruptions Meteorite impacts Meteorite impacts

11. Runup Maximum height above sea level reached by a tsunami when it reaches shore Maximum height above sea level reached by a tsunami when it reaches shore

12. Inundation Horizontal distance from the normal water's edge reached by a tsunami Horizontal distance from the normal water's edge reached by a tsunami

13. Hilo after 1946 tsunami

14. 1952 Tsunami wave passing under bridge at Haleiwa Kaiaka Bay

15. 1946 tsunami -- Hilo harbor: 159 fatalities

16. Beach in Laie, O`ahu before tsunami generated by 1957 quake in Aleutians

19. 1983 Japan tsunami -- water recedes

20. 1983 tsunami in Japan 104 people drowned 700 boats, 59 houses destroyed $800 Million property damage

24. 2000

27. S.E. O`ahu Field Trip Saturday, October 30 & Nov. 6 Saturday, October 30 & Nov. 6 8:30 am – 3 pm 8:30 am – 3 pm Meet Here at 8:30 am Meet Here at 8:30 am We will see Diamond Head, Hanauma Bay, Koko Crater, Castle Junction We will see Diamond Head, Hanauma Bay, Koko Crater, Castle Junction Bring water, hat, sun screen, walking shoes Bring water, hat, sun screen, walking shoes Worth 30 pt. Additional Credit Worth 30 pt. Additional Credit