Chapter 14 Section 2 Ocean Waves Mrs. Mannel Earth Science

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

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

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

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

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

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

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

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