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Tsunamis

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Describe on the site ( http://www.to-hawaii.com/natural-disasters.php) the writer notes that"Hawaii is the U.S state most proned for a Tsunami where it happens about once a year and a very dangerous one happening every seven years. One of the most destructive Tsunamis that occured killing 159 people with property damages totaling $ 26 million was the resulting tsunami caused by an earthquake that occured in the Aleutian Islands of Alaska."
 
 
 

Here are 3 Ariel views of a tsunami wave getting to close!

First Wave
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Looks like a normal beach wave

Pictures Source:
 

A tsunami consists of a series of waves created by a body of water like an ocean. The most popular cause of a Tsunami are usually earthquakes, volcanoes, mass movements below and above water, underwater explosions, and landslides. Again we are dealing with plate tectonics and the energy released in the earth's crust. It is eather a compressional, tensional or shear stress. Tsunami's can result in minor damage or devasting loss.
 
 

 

Second wave to hit land
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Getting a little too close

how the "tidal wave" is created:
A Tsunami can be generated when the plate boundaries are moved and the sea floor falls or rises and then the water returns to sea level starts up some low waves were they rapidly spread ocean wide. Most Tsunamis are generated and associated to an earthquake at the subsuction zone because the vertical movement of the sea floor is the most conductive to the forming of a tsunami. 
 
Signs of a Tsunami
Since earthquakes often cause these Tsunami's, when an earthquake is felt, you can almost be sure there will be a Tsunami followed, therefore you could get out of the water and prepare yourself for one of these huge waves.
 
Warnings and Preventions
Although a Tsunami could not be prevent you could at least be prepared for one. Move away from the shore for number one. Also,using a loud warning system to detect and announce Tsnuami is a good way to tell people to go to a safer place before that wave reaches land. The buliding of strong Tsunami walls is another step taken to prevent damage,and floodgates and channels are built to redirect the water. Although, sometimes the gates or walls serve no purpose because the waves could be much much higher then these barrier walls. DL Johnson notes that one of the most important and primary messangers of a natural hazard such as the Tsunamis are "NOAA" which stands for "National Oceanic and Atmospheric Administration", says Johnson. Johnson also mentions that NOAA are important in observing and researching Tsunami.( http://tsunami.noaa.gov/).
 
 

Third wave in the series
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Reaches the housewhich is way too close. Imagine the fourth wave!

The authors of Physical Geology & the Enviroment, describe the waves speed and measurment of a large wind-generated wave to have a wavelenght of 400 m and move in the deep water at a speed of 90 km per hour and in the middle of a hurricane a wave could have a height of 15 m high.( Plummer, McGeary,Carlson, Eyles, Eyles, Physical Geology & the Enviroment, 1st Edition, 2004, Mc-Graw Hill University Ryerson Limited, pg.90).
 
In the textbook Physical Geology & the Enviroment, 1st Canadian Edition, I learned from the authors that during a hurricane the wavelenght could be 160 km and be moving as fast as 725 km per hour but in deep waters the waveheight maybe small compared to when it reaches shore.
 
What causes the great waves to get big ashore is by the bottom of the seafloor. According to Plummer, McGeary, Carlson, and Eyles, "only a few localities have a combination of gently sloping offshore shelf and funnel- shaped bay that foces tsnuamis so amazing heights, where the record height is 85 m in 1971in the Ryukyu islands south of Japan." (Plummer, McGeary,Carlson, Eyles, Eyles, Physical Geology & the Enviroment, 1st Edition, 2004, Mc-Graw Hill University Ryerson Limited, pg.90).
 
Tsunamis are described as shallow-water waves which are different from the wind- generated waves we often see for example, Lake nipissing's large waves on a windy day. 
 
 
Bigger waves can flood land covering 1,000 feet of land and then sucking back debris and even people caught in the wave and bringing them into the wide open ocean.