2004 Indian Ocean Earthquake and Japanese Tsunami
Tsunamis
A tsunami is a series of waves created when a body of water, such as an ocean, is rapidly displaced on a massive scale. Earthquakes, mass movements above or below water, volcanic eruptions and other underwater explosions, landslides, large meteorite impacts and testing with nuclear weapons at sea all have the potential to generate a tsunami. The effects of a tsunami can range from unnoticeable to devastating. The term tsunami comes from the Japanese words(津波、つなみ) meaning harbor ("tsu", 津) and wave ("nami", 波). Although in Japanese tsunami is used for both the singular and plural, in English tsunamis is often used as the plural. The term was created by fishermen who returned to port to find the area surrounding their harbor devastated, although they had not been aware of any wave in the open water. Tsunami are common throughout Japanese history; approximately 195 events in Japan have been recorded. The word tsunami is pronounced tsu-nah-mee or tsoo-nah-mee; /tsʊˈnɑːmi/.
A tsunami has a much smaller 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 passing "hump" in the ocean. Tsunami have been historically referred to as tidal waves because as they approach land, they take on the characteristics of a violent onrushing tide rather than the sort of cresting waves that are formed by wind action upon the ocean (with which people are more familiar). Since they are not actually related to tides the term is considered misleading and its usage is discouraged by oceanographers. [1] Since not all tsunami occur in harbors, however, that term is equally misleading, although it does have the benefit of being misleading in a different language.
Causes
A Tsunami can be generated when the plate boundaries abruptly deform and vertically displace the overlying water. Such large vertical movements of the Earth’s crust can occur at plate boundaries.
A tsunami is a series of waves created when a body of water, such as an ocean, is rapidly displaced on a massive scale. Earthquakes, mass movements above or below water, volcanic eruptions and other underwater explosions, landslides, large meteorite impacts and testing with nuclear weapons at sea all have the potential to generate a tsunami. The effects of a tsunami can range from unnoticeable to devastating. The term tsunami comes from the Japanese words(津波、つなみ) meaning harbor ("tsu", 津) and wave ("nami", 波). Although in Japanese tsunami is used for both the singular and plural, in English tsunamis is often used as the plural. The term was created by fishermen who returned to port to find the area surrounding their harbor devastated, although they had not been aware of any wave in the open water. Tsunami are common throughout Japanese history; approximately 195 events in Japan have been recorded. The word tsunami is pronounced tsu-nah-mee or tsoo-nah-mee; /tsʊˈnɑːmi/.
A tsunami has a much smaller 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 passing "hump" in the ocean. Tsunami have been historically referred to as tidal waves because as they approach land, they take on the characteristics of a violent onrushing tide rather than the sort of cresting waves that are formed by wind action upon the ocean (with which people are more familiar). Since they are not actually related to tides the term is considered misleading and its usage is discouraged by oceanographers. [1] Since not all tsunami occur in harbors, however, that term is equally misleading, although it does have the benefit of being misleading in a different language.
Causes
A Tsunami can be generated when the plate boundaries abruptly deform and vertically displace the overlying water. Such large vertical movements of the Earth’s crust can occur at plate boundaries.