A tsunami is a series of waves that is created when a large volume of a body of water, such as an ocean, is rapidly displaced. Earthquakes, volcanic eruptions and other underwater explosions (detonations of nuclear devices at sea), landslides, bolides impacts, and other mass movements above or below water all have the potential to generate a tsunami. Due to the immense volumes of water and energy involved, the effects of tsunamis can be devastating. Some meteorological storm conditions such as deep depressions causing cyclones, hurricanes, can generate a storm surge which can be several meters above normal tide levels. This is due to the low atmospheric pressure within the centre of the depression. As these storm surges come ashore, they may resemble (though are not) tsunamis, inundating vast areas of land.
While everyday wind waves have a wavelength (from crest to crest) of about 100 meters (330 ft) and a height of roughly 2 meters (6.6 ft), a tsunami in the deep ocean has a wavelength of about 200 kilometers (120 mi). This wave travels at well over 800 kilometers per hour (500 mph), but due to the enormous wavelength the wave oscillation at any given point takes 20 or 30 minutes to complete a cycle and has amplitude of only about 1 meter (3.3 ft). This makes tsunamis difficult to detect over deep water. Their passage usually goes unnoticed by ships.
As the tsunami approaches the coast and the waters become shallow, the wave is compressed due to wave shoaling and its forward travel slows below 80 kilometers per hour (50 mph). Its wavelength diminishes to less than 20 kilometers (12 mi) and its amplitude grows enormously, producing a distinctly visible wave. Since the wave still has a wavelength on the order of several kilometers (a few miles), the tsunami may take minutes to ramp up to full height, with victims seeing a massive deluge of rising ocean rather than a cataclysmic wall of water. Open bays and coastlines adjacent to very deep water may shape the tsunami further into a step-like wave with a steep breaking front.
A tsunami can be generated when converging or destructive plate boundaries abruptly move and vertically displace the overlying water. It is very unlikely that they can form at divergent (constructive) or conservative plate boundaries. This is because constructive or conservative boundaries do not generally disturb the vertical displacement of the water column. Subduction zone related earthquakes generate the majority of all tsunamis.
Tsunamis have a small amplitude (wave height) offshore, and a very long wavelength (often hundreds of kilometers long), which is why they generally pass unnoticed at sea, forming only a slight swell usually about 300 mm above the normal sea surface. They grow in height when they reach shallower water, in a "shoaling" process described below. A tsunami can occur at any state of the tide and even at low tide will still inundate coastal areas if the incoming waves surge high enough.
As a conclusion, tsunamis can destroy everything like the building, items, animals, humans and so on. We cannot avoid this since this is a natural disaster. So, we should more be careful when we play beside the seashore.
While everyday wind waves have a wavelength (from crest to crest) of about 100 meters (330 ft) and a height of roughly 2 meters (6.6 ft), a tsunami in the deep ocean has a wavelength of about 200 kilometers (120 mi). This wave travels at well over 800 kilometers per hour (500 mph), but due to the enormous wavelength the wave oscillation at any given point takes 20 or 30 minutes to complete a cycle and has amplitude of only about 1 meter (3.3 ft). This makes tsunamis difficult to detect over deep water. Their passage usually goes unnoticed by ships.
As the tsunami approaches the coast and the waters become shallow, the wave is compressed due to wave shoaling and its forward travel slows below 80 kilometers per hour (50 mph). Its wavelength diminishes to less than 20 kilometers (12 mi) and its amplitude grows enormously, producing a distinctly visible wave. Since the wave still has a wavelength on the order of several kilometers (a few miles), the tsunami may take minutes to ramp up to full height, with victims seeing a massive deluge of rising ocean rather than a cataclysmic wall of water. Open bays and coastlines adjacent to very deep water may shape the tsunami further into a step-like wave with a steep breaking front.
A tsunami can be generated when converging or destructive plate boundaries abruptly move and vertically displace the overlying water. It is very unlikely that they can form at divergent (constructive) or conservative plate boundaries. This is because constructive or conservative boundaries do not generally disturb the vertical displacement of the water column. Subduction zone related earthquakes generate the majority of all tsunamis.
Tsunamis have a small amplitude (wave height) offshore, and a very long wavelength (often hundreds of kilometers long), which is why they generally pass unnoticed at sea, forming only a slight swell usually about 300 mm above the normal sea surface. They grow in height when they reach shallower water, in a "shoaling" process described below. A tsunami can occur at any state of the tide and even at low tide will still inundate coastal areas if the incoming waves surge high enough.
As a conclusion, tsunamis can destroy everything like the building, items, animals, humans and so on. We cannot avoid this since this is a natural disaster. So, we should more be careful when we play beside the seashore.
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