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By:AKASH.RVIIIth B

C.K.S English SchoolHASSAN

TSUNAMI

A tsunami (plural: tsunamis or tsunami; from Japanese: 津波 , lit. "harbour wave";[1] English pronunciation: /suːˈnɑːmi/ soo-NAH-mee or /tsuːˈnɑːmi/ tsoo-NAH-mee[2]) is a series of water waves caused by the displacement of a large volume of a body of water, generally an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explosions (including detonations of underwater nuclear devices), landslides, glacier calvings, meteorite impacts and other disturbances above or below water all have the potential to generate a tsunami.[3]

Tsunami waves do not resemble normal sea waves, because their wavelength is far longer. Rather than appearing as a breaking wave, a tsunami may instead initially resemble a rapidly rising tide, and for this reason they are often referred to astidal waves. Tsunamis generally consist of a series of waves with periods ranging from minutes to hours, arriving in a so-called "wave train".[4] Wave heights of tens of metres can be generated by large events. Although the impact of tsunamis is limited to coastal areas, their destructive power can be enormous and they can affect entire ocean basins; the 2004 Indian Ocean tsunami was among the deadliest natural disasters in human history with at least 290,000 people killed or missing in 14 countries bordering the Indian Ocean.

TSUNAMI

TSUNAMI IN ANDAMAN &

NICOBAR

Map of Tsunami

A severe earthquake measuring 8.9 Richter scale, was felt in Andaman and Nicobar Islands having epicentre at 3.7N and 95E off the island of Sumatra between 0630 to 0635 hours in the morning of 26th December, 2004. The quake was followed the "Killer Waves" or Tsunami which caused  extensive damages to life & property in this archipelago. But we would like to draw the attention of all about the true picture of the effect/damage. The maximum damage has been in the Nicobar group of Islands and NOT in the Andaman group of islands. If you look at the map of the Andaman & Nicobar Islands , you will find that Andaman & Nicobar are two completely different group of islands. The entire Andaman group of islands (excepting Little Andamans) have been literally spared from the devastating Tsunami.  Most importantly there has been no injuries or deaths amongst tourists - since tourists are anyway not allowed to visit the Nicobar group of islands.Things are now fast coming back to normal here. Since, there has been no big damage in any of the major/popular tourist spots/destinations (like Port Blair, Havelock, Neil island, etc.) - Indian Airlines & Jet Airways have restarted their daily scheduled flights from Kolkata (Calcutta) & Chennai (Madras) and tourists are now allowed to come here once again.  There was a temporary prohibition (just as a precautionary measure) on scuba diving for sometime - which has also now been removed. So, tourists can now once again go for diving, snorkeling, game fishing, etc. 

TSUNAMI IN ANDAMAN & NICOBAR

TSUNAMI INPORT BLAIR (THAI LAND)

Tsunamis are large waves of water usually triggered by an earthquake, explosion or other event displacing a large amount of water. Out in the open ocean, tsunamis are typically harmless and unnoticeable to the naked eye. When they start, tsunami waves are small and wide -- the height of the waves can be as small as a foot, and they can be hundreds of miles long and move very quickly, so they can pass practically unnoticed until the get to shallow water closer to land. But as the distance between the bottom of the ocean floor and the water gets smaller, these short, wide, fast waves compress into extremely high, powerful waves that wash onto land. Depending on the amount of energy involved, they can reach more than 100 feet in height. Read more about tsunamis.The 2004 Tsunami, referred to as the 2004 Indian Ocean Tsunami, the 2004 Indonesian Tsunami or the 2004 Boxing Day Tsunami, was one of the worst natural disasters in recorded history. It was triggered by an undersea earthquake with an estimated magnitude of between 9.1 to 9.3, making it the third most powerful quake ever recorded.The tsunami that the massive earthquake generated killed more than 230,000 people in Indonesia, Sri Lanka, India and Thailand, displaced hundreds of thousands of people and caused billions of dollars in property damage.

TSUNAMI INPORT BLAIR (THAI LAND)

Map of Tsunami

BEFORE & AFTER

Tilly Smith (born 1994) is a British woman who, as a girl aged 10, was credited with saving nearly a hundred foreign tourists at Maikhao Beach in Thailand by warning beachgoers minutes before the arrival of the tsunami caused by the 2004 Indian Ocean earthquake.Tilly Smith learned about tsunamis in a geography lesson two weeks before the tsunami from her teacher Andrew Kearney at Danes Hill School in Oxshott, Surrey. She recognised the symptoms of receding water from the shoreline and frothing bubbles on the surface of the sea and alerted her parents, who warned others on the beach and the staff at the hotel on Phuket where they were staying. The beach was evacuated before the tsunami reached shore, and was one of the few beaches on the island with no reported casualties.At Danes Hill Preparatory School a cameraman was allowed to follow Smith around for a day to find out what she normally did at school.

TILLY SMITH

TSUNAMI IN GALLE (SRI-LANKA)

The country of Sri Lanka (formerly Ceylon), located 31 miles off the south-eastern coast of India, was hit by a tsunami triggered by a 9.0 magnitude earthquake off the coast of Sumatra on December 26, 2004. The tsunami was one of the worst disasters ever recorded in Sri Lankan history. The tsunami left tens of thousands dead, many more homeless, and caused widespread chaos throughout the island. In addition to the human impacts, the tsunami had widespread effects on Sri Lanka's environment and ecosystems. It is still too early to express the long-term effects caused by the tsunami, but short-term effects are clearly evident.Human ImpactsCivilian casualties in Sri Lanka were second only to those in Indonesia (see Indonesia). Reports vary on the number of deaths since many people are still missing and the country lacks adequate communications. As of March 1, 2005, estimates state that 36,603 people perished in the months following the tsunami. Another 800,000 people living on the coasts of Sri Lanka have been directly affected. The eastern shores of Sri Lanka faced the hardest impact since they were facing the epicenter of the earthquake. The southwestern shores were hit later, but the death toll was just as severe. The coastal lifestyle of people in Sri Lanka contributed to the high death tolls. The following images illustrate the correlation between population, affected areas, and mortality rates. In addition to the high number of fatalities, approximately 90,000 buildings were destroyed. Houses were easily destroyed since they were built mostly from wood. This wooden debris that was left behind is now raising issues of its own 

TSUNAMI IN GALLE

HOW TSUNAMI FORMS

HOW TSUNAMI FORMS

The term tsunami has its origins in the Japanese language; an English equivalent is "seismic sea waves." Tsunamis are often incorrectly interchanged with the term" tidal waves," which refer to high waves of water caused by changes in the flow and surge of the ocean. Tsunamis, on the other hand, can be caused by a few different means: 1) the down drop or upthurst of the Earth’s crust which results in an earthquake; 2) a large-scale undersea landslide; 3) a submarine volcanic eruption of a certain degree; or potentially, 4) a large meteor impact at sea. The vast majority of tsunamis result from earthquakes. (Source: The Great Waves).    aHow Earthquakes Cause TsunamisThe illustration below shows a subduction earthquake (one where a denser plates shifts below its neighboring plate, at left). Energy is transferred and the displaced water forms a wave. As the wave travels and enters shallower water in the coastal area, it begins to increase in amplitude (National Geographic). Killer Wave! Tsuanmi--National Geographic KidsTsunamis are not always colossal waves when they come into the shore. In fact, "... most tsunamis do not result in giant breaking waves (like normal surf waves at the beach that curl over as they approach shore). Rather, they come in much like very strong and very fast tides (i.e., a rapid, local rise in sea level)." (USGS website) Nevertheless, there is destruction of life and of property by floating debris and impact of water. The tsunami produces a series of rushing waves and also a series of withdrawals.

HOW TSUNAMI FORMS

BEFORE & AFTER