Chapter 14 Section 2 Ocean Waves

1. Chapter 14 Section 2 Ocean Waves Mrs. Mannel Earth Science

2. Anatomy of a Wave • Crest – the highest point of a wave • Trough – the lowest point • Wavelength – the distance from crest to crest OR trough to trough • Wave height – vertical distance from crest to trough

3. Wave Formation & Movement • http://www.onr.navy.mil/focus/ocean/motion/waves1.htm • The energy transferred through waves does not displace water, just the energy • The rising and falling of the water creates circular currents underneath the surface

4. Types of Waves • Deep -water waves are waves that that move in water that is deeper than ½ of their wavelength • When the waves reach water that is shallower than ½ their wavelength, they turn into shallow-water waves

5. Breakers and Surf • The area between the breaker zone and the shore is called the surf • Here is where the undertow is created

6. Types of Waves • Open-ocean waves are sometimes called whitecaps because of their steep crests • They usually form in rough seas in the open ocean and typically do not last long • Swells are formed from calmer winds and have longer wavelengths

7. Tsunamis • Tsunamis are typically formed from earthquakes, but can also happen as a result of volcanic eruptions, landslides, underwater explosions and meteor impacts • They can reach heights of 30 meters

8. 2004 Tsunami • http://pubs.usgs.gov/circ/c1187/

9. Storm Surges • A storm surge is a local rise in sea level as the result of strong winds created by hurricanes • The can reach heights of 8 meters • The storm surge that was created in Hurricane Katrina was around 8 m or 25 feet