Q: How are tsunamis are created? <ul><li>A: They are created by earthquakes, volcanic eruptions, or giant under waterslide. </li></ul>
Q: What makes them so powerful? <ul><li>A: They carry the weight of the ocean’s depth with them and they can also travel at speeds of up to 800km/h. When this energy is squeezed into shallow waters, it becomes concentrated and the waves speeds up and increases in height . </li></ul>
Q: How are tsunamis are different than wind waves? <ul><ul><ul><li>A: The energy in a wind generated wave is usually half as deep as the wave height. This is why they diminish easily. There is not enough energy to push the water. They also generally have a wave length of a few meters at best. This is why they do not push on shore very far. A tsunami is caused by the up-lifting of the ocean floor, or an underwater volcano, and the energy "fills the entire water column from the ocean floor to the surface; they can have wavelengths of 100 miles or better and travel at speeds upwards of 500mph. As these waves enter shallow water, they slow at the leading edge, which causes the water to "pile up". With the long wave length, this causes the water to come on shore for extended periods which causes the disaster. </li></ul></ul></ul>
Q: If you were floating in water and a wave caught you, would you just get moved along the surface of the wave?
Q: How do waves shape the shoreline? <ul><li>A: In calm conditions, waves generally “build” beaches that have mobile sediment (sand, gravel and cobble) by transporting sediment onshore. During storms, strong currents under the breakers (“undertows”) draw water and sediment back from the beach; this causes beach erosion. </li></ul>
Q: What are negative and positive effects of waves on costal areas? <ul><li>A: Negative effects are that it causes cliff to collapse, sometimes resulting in injury, death, and property damage. </li></ul><ul><li>Positive effects are tourists are drawn to areas that are famous for surfing and to areas where erosion by waves has carved out spectacular scenery. </li></ul>
Q: What is a breakwater and what’s positive and negative about them? <ul><li>A: A breakwater is used to protect the mill. Where thw water is 50m deep just offshore, a floating breakwater is used. </li></ul><ul><li>They are good because it has artificial reef that is home to some largest octopuses in the world. </li></ul><ul><li>They are bad because they can alter behavior of waves on nearby coastlines. This may erosion on the beach that was previously affected. </li></ul>
<ul><li>The End </li></ul><ul><li>Thank You </li></ul>