Waves and Tsunamis

1. Waves and Tsunamis Danny Nolan and Lara Canham

2. Waves Waves are described by two independent variables: Frequency- number of cycles Wavelength- distance between any point on a wave and the corresponding point on the next wave And by: amplitude- the height of the crest of each wave

3. Uniqueness of Water *Solvent properties- great solvent power as a result of its polarity, bent shape, and H-bonding ability *high surface tension and high capillarity *Bonding water molecules form a hexagonal, open structure which explains the beauty in snowflakes *solid state of water is less dense than the liquid state *high specific heat and high heat of vaporization, which combine to give the Earth and its organisms a narrow temperature range

4. How water waves are formed The winds cause waves on the surface of the ocean. The wind transfers some of its energy to the water, through friction between the air molecules and the water molecules. Stronger winds (like storm surges) cause larger waves. http://www.enchantedlearning.com/

5. Water waves • There are two types of wave motion, longitudinal (particle displacement is parallel to the direction of the wave) and transverse (particle displacement is perpendicular to the direction of the wave), and water waves are a combination of both. As a wave travels through the waver, the particles travel in clockwise circles. The radius of the circles decreases as the depth into the water increases. • Simulation of Water Waves http://www.kettering.edu

6. Tsunamis

8. Tsunamis can be created by underwater earthquakes (usually plate subduction), underwater volcanic eruptions, a submarine rockslide, and, very rarely, an asteroid or a meteoroid crashing into the water. The vast majority of tsunamis are caused by underwater earthquakes. However, the magnitude of the earthquake must be at least 6.75 on the Richter Scale in order for it to cause a tsunami. http://www.enchantedlearning.com/

9. Tsunami Formation

10. In general, tsunamis have extremely long wavelengths, as great as seven hundred miles in between crests. The period (length of time between two waves) can also be very large. In deep water, it can as long as an hour. Tsunamis are also very fast moving. They can travel in excess of 970 kph (600 mph) while in the open ocean. When it begins to reach the coast, it slows down to between 30 and 200 mph. http://www.enchantedlearning.com/

11. When tsunami waves approach land, the ocean becomes increasingly more shallow. As the troughs of each wave hits the ocean floor, it slows the wave down, decreases the wavelength, and increases the amplitude of the wave. At landfall, the height of the wave can be as much as hundreds of meters tall. In addition to the waves themselves, the tsunamis push a large amount of water on the shoreline far above the regular sea level http://www.enchantedlearning.com/

13. Microsoft Encarta

14. Comparison of water waves Normal waves (waves caused by the wind) are drastically different than tsunami waves. Tsunami waves are far faster with a much longer wavelength than waves caused by winds. In the deep sea, tsunami waves are very small and virtually indistinguishable from regular waves, but as they approach shorelines, the tsunami waves are substantially larger than wind-induced waves. http://www.enchantedlearning.com/