Tsunami 2
Tsunamis have occurred on many occasions all around the world. Volcanic eruptions, landslides, earthquakes, and other natural disasters have caused these massive waves. A tsunami is a towering ocean wave generated by tectonic displacements such as undersea earthquakes, landslides, cosmic collisions, or volcanic eruptions. There is a common misconception that a tsunami is a tidal wave. Although the impact of a tsunami on a coastline may change depending upon the tidal level at the time when one occurs, tsunami waves are unrelated to tides. In the open, the water level may rise and fall several feet as a tsunami passes by. But as a tsunami approaches the coastline, it can form a deadly wall of water that rises more than 100 feet high. The most frequent cause of tsunamis is earthquakes. A tsunami that is caused by an undersea earthquake is also called seismic sea wave. When the sea floor abruptly deforms and vertically displaces the overlying water a tsunami can be generated. Consequently, as the displaced water mass tries to return to its original position, waves are created. On July 9, 1958, the largest tsunami waves produced by a landslide occurred at Lituya Bay in Al
As the water depth decreases, the tsunami slows whereas the energy current stays almost constant despite its being reliant on both the wave speed and height. Tsunamis usually have wavelengths equal to the water depth (up to several thousand meters) at the point of origin. When tsunami waves finally encounter land, they begin to loose energy as they run up the shore. The shape of the near-shore seafloor, or local submarine topography, has an extreme effect on how tsunami waves behave. If a reflected wave interferes with another wave, large wave heights may occur at unexpected locations. The first sign of a tsunami would typically be a significant recede of increase of the water level depending upon which part of the tsunami wave train arrives at the shore first. A wave crest is known for bringing a rise in the water level. Tsunamis are generally very large in bays. This is very different from ordinary waves. The characteristics of tsunamis as they approach shore are greatly affected by wave refraction over the local bathymetry. The height and intensity of a tsunami wavešs impact on the shoreline may be significantly reduced if an extensively developed coral reef exists cl
Some common words found in the essay are:
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Approximate Word count = 793
Approximate Pages = 3 (250 words per page double spaced)
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