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The
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Aftermath Of The Tsunami And Its Devastations As Aspirations And Hopes Are Expressed In Retrospect!Sri Lanka together with many other nations in the Asian Region of the
Bay of Bengal is reeling from the devastation of a mighty Tsunami which
struck in the morning hours of Sunday December 28th along its coastal
belt as outpourings of grief, consolation anf foreign aid are beginning
to filter in and the Island Nation is gripped in apprehension and fear
of further aftershocks. Ironically A single wave station south of the earthquakes epicentre
registered Tsunami activity less than 2 feet (60 centimetres) high heading
south toward Australia, according to the latest reports and speculations
are rife about the diversity of what such a recording might have had in
the best interests of the now affected areas had they been warned which
unfortunately did not manifest itself to their advantage in what may perhaps
go down in history as the greatest faux pas of meteorological and seismic
monitoring for which the Nations affected have probably only themselves
to blame notwithstanding the assumed conclusioin that the areas affected
, primarily Sri Lanka and South India were never endangered rather erroneously
and the price paid! The northern tip of the earthquake fault is located near the Andaman Islands, and tsunamis appear to have rushed eastward toward the Thai resort of Phuket this morning when the community was just stirring. They had no tidal gauges and they had no warning and there are no buoys in the Indian Ocean where this tsunami occurred. The tsunami was triggered by the most powerful earthquake recorded in the past 40 years. The earthquake, whose magnitude was a staggering 8.9, unleashed walls of water more than two storeys high to the west across the Bay of Bengal, slamming into coastal communities 1,000 miles (1,600 kilometres) away. Hours after the quake, Sumatra was struck by a series of powerful aftershocks. The earthquake broke on a fault line deep off the Sumatra coast, running north and south for about 600 miles (965 kilometres) or as far north as the Andaman and Nicobar islands between India and Mynamar. Its a huge rupture and its conceivable that the sea floor deformed all the way along that rupture, and thats what initiates tsunamis. Tsunamis as large and destructive as todays typically happen only a few times in a century. A tsunami is not a single wave, but a series of travelling ocean waves generated by geological disturbances near or below the ocean floor. With nothing to stop them, these waves can race across the ocean like the crack of a bullwhip, gaining momentum over thousands of miles. Most are triggered by large earthquakes but they can be caused by landslides, volcanoes and even meteor impacts. The waves are generated when geologic forces displace sea water in the ocean basin. The bigger the earthquake, the more the Earths crust shifts and the more seawater begins to move. Most tsunamis occur in the Pacific because the ocean basin is rimmed by the Ring of Fire, a long chain of the Earths most seismically active spots. Marine geologists recently have determined that under certain conditions, the US East Coast and other heavily populated coastlines also could be vulnerable. In a tsunami, waves typically radiate out in directions opposite from the seismic disturbance. In the case of the Sumatra quake, the seismic fault ran north to south beneath the ocean floor, while the tsunami waves shot out west and east. Tsunamis are distinguished from normal coastal surf by their great length and speed. A single wave in a tsunami series might be 100 miles (160 kilometres) long and race across the ocean at 600 mph (965 kph). When it approaches a coastline, the wave slows dramatically, but it also rises to great heights because the enormous volume of water piles up in shallow coastal bays. And unlike surf, which is generated by wind and the gravitational tug of the moon and other celestial bodies, tsunamis do not break on the coastline every few seconds. Because of their size, it might take an hour for another one to arrive. Some tsunamis appear as a tide that doesnt stop rising, while others are turbulent and savagely chew up the coast. Without instrumentation, so little is known about this tsunami that researchers must wait for eyewitness accounts to determine its characteristics. It was a big tsunami, but it is hard to say exactly how many waves there were or what happened. In the hours following an earthquake, tsunamis eventually lose their power to friction over the rough ocean bottom or simply as the waves spread out over the oceans enormous surface. The international warning system was started in 1965, the year after tsunamis associated with a magnitude 9.2 quake which struck Alaska in 1964. It is administered by the National Oceanic and Atmospheric Administration. Member states include all the major Pacific rim nations in North America, Asia and South America, as well as the Pacific islands, Australia and New Zealand. It also includes France, which has sovereignty over some Pacific islands, and Russia. However, India and Sri Lanka are not members. Thats because tsunamis are much less frequent in the Indian Ocean. The warning system analyses earthquake information from several seismic networks, including the US Geological Service. The seismic information is fed into computer models that picture how and where a tsunami might form. It dispatches warnings about imminent tsunami hazards, including predictions how fast the waves are travelling and their expected arrival times in specific geographic areas. As the waves rush past tidal stations in the ocean, bulletins updating the tsunami warning are issued. Other models generate inundation maps of what areas could be damaged, and what communities might be spared. Not all earthquakes generate tsunamis. The warning centre typically does not issue warnings for earthquakes below magnitude 7.0, which are still unusually powerful events." end quote |
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