1. Ocean Motion
Part 1: Waves
Mr. Coleman

2. ? Why does the Ocean have waves? What are the parts of a wave?
How does water move in a wave?
What happens when a wave hits a beach?

3. Wave – a rhythmic movement that carries energy through matter or space (in the ocean, seawater)

4. Most waves are caused by …
WIND!
Friction from wind over water causes water to move. If the wind speed is high enough, water begins to pile up to form a wave.

5. Wave height is determined by 3 factors:
1.Wind Speed 2.Wind Duration (length of time wind blows) 3.“Fetch” (Extent of open water across which the wind can blow)

6. Amplitude – ½ the wave height

7. How does water move in a wave?
Some clues:
When you were at the beach, you probably noticed that the edge of the water goes back and forth with the waves.
If you float an object on the ocean, it stays roughly in one place. It is not pushed forward by the waves.

8. Particles of water move around in circles
Particles of water move around in circles The farther below the surface, the smaller the circle.

9. At the beach:
Wavelength decreases and wave height increases as waves approach the shore.
Constant
Wavelength
Waves drag against the bottom
and wave length decreases

10. As the wave slows, its crest and trough come closer together
As the wave slows, its crest and trough come closer together. The top of the wave is not slowed by friction and moves faster than the bottom, causing waves to break.
The top of the wave outruns the bottom and falls over. This collapsing wave is called a breaker.

11. Noteable “Big Wave” Locations
Australia
California
Hawaii
Chile
Portugal
Spain
Mexico
South Africa
Fiji

12. Tsunamis

13. Tsunami

14. 3. Harnessing Wave Energy
2. Stormsurfers
1. Big Wave Surfing