jasonparker
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The South Asian earthquake of 26 December 2004, the largest in the last 40 years and fifth largest since 1900, registering 9 on the Richter scale, and the tsunami that followed it, caused a disaster leading to the deaths of more than 156,000 people. 1,000 square-kilometre faults that appeared as the result of the movement of great underground plates and the enormous energy created by land masses changing place combined with the great energy occurring in the oceans to create tsunamis. The tsunamis struck the South Asian countries of Indonesia, Sri Lanka, India, Malaysia, Thailand, Bangladesh, Myanmar, the Maldives and the Seychelles, and even the coast of the African country of Somalia, some 5,000 kilometres away.
The word "tsunami," meaning harbour wave in Japanese, became part of the languages of the world in the aftermath of the 15 June, 1896, Great Meiji Tsunami that hit Japan and in which 21,000 people lost their lives.
In order to understand the tsunami, it is most important to distinguish the tsunami from tides and waves formed by the wind. Winds blowing over the surface of the ocean set up a current limited to the upper layer of the sea by raising relatively small waves. For example; divers with air-bottles can easily dive down and reach still water. There may be waves of 30 metres or more in violent storms, but these do not set the deep waters in motion. In addition, the speed of a normal wind wave is up to 20 km/hour, while one feature of the tsunami wave is that it travels at 750-800 km/hour. The tides move over the Earth twice in the course of a day and, just like tsunamis, can produce currents that reach down to the sea bed. In contrast to genuine tidal waves, however, the source of tsunamis is not the gravitational force of the Moon and Sun.
The tsunami represents a long-period sea wave that forms due to energy passing into the sea because of earthquakes, volcanic explosions and strata collapses connected to these in the ocean or sea bed, tectonic events such as underwater plate slides, or meteor effects. When the ocean floor changes place at high speed, the whole mass of water above it is affected. What happens in the sea floor is reflected on the surface of the water, and the whole mass of water, down to a depth of 5,000-6,000 metres, joins in the wave motion. Consecutive swelling and falling may cover an area of up to 10,000 square kilometres.
Tsunamis Have No Effect in Open Seas
In the open ocean, tsunamis are not the enormous walls of water that most people would imagine; they are generally less than 1 metre high, with a wave length of around 1,000 kilometres. As can be seen from this, the wave surface is very slightly inclined (1 cm in 1 km). In deep and open ocean regions, these waves go unperceived, despite moving at the high speed of 500 to 800 km/hour, since they are masked by normal surface waves. In order to better comprehend the speed of the wave, we may say that it could compete with that of a Boeing 747 jet. A tsunami that takes place in the open sea will not even be felt by any vessels.
Tsunamis Depositing 100,000 Tons of Water on Land
Research has shown that rather than consisting of a single wave, tsunamis actually consist of a series of waves with a single centre, like a stone thrown into a swimming pool. The distance between two consecutive waves may be 500-650 kilometres. This means the tsunami can cross the ocean in a matter of hours. The tsunami only reveals its enormous energy when it approaches the shore. Energy distributed in a thick column of water becomes concentrated as that column increasingly contracts and a rapid increase in the height of the surface wave can be observed. Waves less than 60 cm high in open ocean waters lose speed as they approach shallow waters, the distance between the waves decreases, and waves piling on top of others create the tsunami by forming a wall of water. These giant waves, that are generally 15 metres high and rarely exceed 30 metres, use enormous force against the shore they strike with great speed, inflict serious damage, and cause considerable loss of life.
The tsunami deposits more than 100,000 tons of water for every metre of shoreline, with a hard-to-imagine destructive force. (The tsunami that struck Japan in July, 1993, the largest known tsunami ever, rose 30 metres above sea level.) The first sign that a tsunami is approaching is usually not a wall of water, but the sudden retreat of the sea.
continue : http://www.harunyahya.com/articles/33tsunami.php
The word "tsunami," meaning harbour wave in Japanese, became part of the languages of the world in the aftermath of the 15 June, 1896, Great Meiji Tsunami that hit Japan and in which 21,000 people lost their lives.
In order to understand the tsunami, it is most important to distinguish the tsunami from tides and waves formed by the wind. Winds blowing over the surface of the ocean set up a current limited to the upper layer of the sea by raising relatively small waves. For example; divers with air-bottles can easily dive down and reach still water. There may be waves of 30 metres or more in violent storms, but these do not set the deep waters in motion. In addition, the speed of a normal wind wave is up to 20 km/hour, while one feature of the tsunami wave is that it travels at 750-800 km/hour. The tides move over the Earth twice in the course of a day and, just like tsunamis, can produce currents that reach down to the sea bed. In contrast to genuine tidal waves, however, the source of tsunamis is not the gravitational force of the Moon and Sun.
The tsunami represents a long-period sea wave that forms due to energy passing into the sea because of earthquakes, volcanic explosions and strata collapses connected to these in the ocean or sea bed, tectonic events such as underwater plate slides, or meteor effects. When the ocean floor changes place at high speed, the whole mass of water above it is affected. What happens in the sea floor is reflected on the surface of the water, and the whole mass of water, down to a depth of 5,000-6,000 metres, joins in the wave motion. Consecutive swelling and falling may cover an area of up to 10,000 square kilometres.
Tsunamis Have No Effect in Open Seas
In the open ocean, tsunamis are not the enormous walls of water that most people would imagine; they are generally less than 1 metre high, with a wave length of around 1,000 kilometres. As can be seen from this, the wave surface is very slightly inclined (1 cm in 1 km). In deep and open ocean regions, these waves go unperceived, despite moving at the high speed of 500 to 800 km/hour, since they are masked by normal surface waves. In order to better comprehend the speed of the wave, we may say that it could compete with that of a Boeing 747 jet. A tsunami that takes place in the open sea will not even be felt by any vessels.
Tsunamis Depositing 100,000 Tons of Water on Land
Research has shown that rather than consisting of a single wave, tsunamis actually consist of a series of waves with a single centre, like a stone thrown into a swimming pool. The distance between two consecutive waves may be 500-650 kilometres. This means the tsunami can cross the ocean in a matter of hours. The tsunami only reveals its enormous energy when it approaches the shore. Energy distributed in a thick column of water becomes concentrated as that column increasingly contracts and a rapid increase in the height of the surface wave can be observed. Waves less than 60 cm high in open ocean waters lose speed as they approach shallow waters, the distance between the waves decreases, and waves piling on top of others create the tsunami by forming a wall of water. These giant waves, that are generally 15 metres high and rarely exceed 30 metres, use enormous force against the shore they strike with great speed, inflict serious damage, and cause considerable loss of life.
The tsunami deposits more than 100,000 tons of water for every metre of shoreline, with a hard-to-imagine destructive force. (The tsunami that struck Japan in July, 1993, the largest known tsunami ever, rose 30 metres above sea level.) The first sign that a tsunami is approaching is usually not a wall of water, but the sudden retreat of the sea.
continue : http://www.harunyahya.com/articles/33tsunami.php
