Causes, effects and geographical distribution of earthquakes. Since 1850 alone, tsunamis have been responsible for the loss of more than 430,000 lives. This has the same effect of dropping a large stone into a pool. Energy accumulates in the overriding plate until it exceeds the frictional forces between the two stuck plates.
On the other hand a tsunami is the most destructive force. Tsunami is a series of water waves caused by thedisplacement of a large volume of a body of water, usually an ocean 3. Tsunamis travel across the open ocean at great speeds and build into large deadly waves in the shallow water of a shoreline. Though it is providing good data, earthquakes will not always cause a tsunami if it is side to side. May 18, 2017 here explanation about causes and effects of tsunami. Dec 24, 2014 a megathrust quake caused the tsunami. This is what caused the boxing day tsunami in the indian ocean in 2004 and it is also the reason behind the 2011 japan tsunami. This has the same effect of dropping a large stone into a pool big ripples are created. Earthquakes, volcanic eruptions and alternative underwater explosions including detonations of underwater nuclear devices. This sudden motion is the cause of the tsunami because it gives an enormous shove to the overlying water. Tsunami retain their energy, meaning they can travel across entire oceans with limited energy loss.
Tsunamis are known for their capacity to violently flood coastlines, causing devastating property damage, injuries and loss of life. Unesco eolss sample chapters natural disasters vol. It was generated by an extremely large earthquake off the northwest coast of the indonesian island of sumatra. With typical waves, water flows in circles, but with a tsunami, water flows straight. The speed of a tsunami depends on the depth of the water its traveling through. Flooding can also carry sewage and toxic substances around an environment, posing a health risk. Hundreds and thousands of people are killed by tsunamis. This quiz and corresponding worksheet gauge your understanding of the cause and effect of a tsunami and the threat to human life after waters have receded. Use tv, radio andor the internet to obtain accurate information.
Information for clinicians can be found in tsunami related information for clinicians general information. Many tsunamis are too small to notice, but some can have a leading wave as tall as 30. A tsunami or wave, additionally called a seismic ocean wave, could be a series of waves during a water body caused by the displacement of an outsized volume of water, usually in an ocean or an outsized lake. A tsunami is a catastrophic ocean wave that is usually caused by a submarine earthquake, an underwater or coastal landslide, or the eruption of a volcano. A tsunami is a very long ocean wave generated by sudden displacement of the sea floor or of the oceanic mass the displacement of an. A tsunami occurs when a large body of water, such as an ocean or sea, experiences displacement that causes a longwavelength wave of water to reach the shore. A tsunami occurs when the ocean floor is disturbed by a seismic event, the ocean floor is either pushed up or down and it creates a quick rise in the water above it.
Approximately 170,000 people of aceh province were killed by this tsunami. Here explanation about causes and effects of tsunami. In recent years massive tsunamis have caused extensive damage in northern sumatra and thailand, parts of japans honshu island, and parts of chile. The most common cause of a tsunami is an earthquake. Scribd is the worlds largest social reading and publishing site. The force of a tsunami causes massive damage and loss of life. A tsunami is a large ocean wave usually caused by an underwater earthquake or a volcanic explosion. Tsunamis slow down when reaching land but increase in height. A free powerpoint ppt presentation displayed as a flash slide show on. Mar 11, 2011 one of the biggest and worst effects of a tsunami is the cost to human life because unfortunately escaping a tsunami is nearly impossible. Causes of tsunami earthquake volcanic eruption underwater explosions meteorite impacts 4. Scientists are still trying to determine the exact cause.
A tsunami is a series of waves in the ocean that can cause great destruction. Remain on alert until the warning is cancelled, as tsunamis may strike repeatedly. Here, we will discuss about what tsunami is, its causes, characteristics of tsunami wave, signs preceding it, most common tsunami occurring areas and also the most destructive tsunamis in the world. Earthquakes, volcanic eruptions and other underwater explosions including.
To understand how earthquakes cause tsunamis we must first fully understand what causes earthquakes. Tsunami causes free download as powerpoint presentation. What causes a tsunami a tsunami is a large ocean wave that is caused by sudden motion on the ocean floor. A tsunami is a series of ocean waves that sends surges of water, sometimes reaching heights of over 100 feet 30. The earthquakes in the sea generate massive waves called tsunami in japanese language. Much like when a rock plunges into a still pond, once a. The word tsunami comprises the japanese wordstsu meaning harbour and nami meaning wave. A tsunami is a sudden violent change in the earths surface resulting from a destructive sea wave caused by an earthquake or volcanic eruption. Often the most destructive tsunamis are caused by earthquakes but causes can also include volcanic eruptions, landslides or even a comet hitting the sea landslides cause tsunamis when the debris falls into the water. The volcanic or earthquake activity usually creates a huge wave underneath the ocean, which eventually come down violently onto the shoreline. The following is a list of general resources related to possible health concerns associated with the recent tsunamis in south asia.
The 2004 indian ocean tsunami reached heights of 65 to 100 feet in sumatra, caused more than 200,000 deaths from indonesia to east africa, and registered on tide gauges throughout the world. Travels 2030 miles per hour with waves 10100 feet high causes flooding and creates. Tsunami safety tips, preparation, and survival facts and. Almost every year, a large earthquake occurs somewhere in the world and captures the publics attention. On december 26, 2004 morning walkers and fishermen residing along the eastern coast of india observed a strange phenomenon of the sea. Additional health information about specific countries can be found on the cdcs travelers health website. The causes of tsunami all tsunamis are caused by the sudden displacement of large volumes of water. Ppt tsunamis powerpoint presentation free to download. The most common cause of a tsunami is an underwater earthquake, but they can also be caused by other events, such as a volcano or underwater landslide. Both the 2004 indian ocean tsunami and the 2011 japan tsunami were more than 100 ft. This sudden motion could be an earthquake, a powerful volcanic eruption, or an underwater landslide. When an earthquake occurs, jma estimates whether a tsunami has been generated. Earthquake rupture in seafloor pushes water upwards starting the tsunami 2. Tidal waves are caused by the forces of the moon, sun, and planets upon the tides, as well as the wind as it moves over the water.
This disturbance can result from earthquakes, volcanic eruptions, submarine slides, meteorites hitting the ocean, or the explosion of nuclear devices near the ocean. If a disastrous tsunami is expected in coastal regions, jma issues a. Tsunamis are known for their capacity to violently flood coastlines, causing devastating property damage, injuries and. They can speed across the ocean as fast as a jet plane, swallow up islands and wipe out villages. Moreover, tsunamis are often referred to high waves of water caused by changes in the flow and surge of the ocean. Tsunamis the movie the impossible starring ewan mcgregor and naomi watts documents an event that was rare, tragic, devastating but far from impossible. Tsunamis cause rapid changes in water levels and create dangerous currents in harbors and ports.
The site uses a mixture of seismic earthquake and oceanographic data to try and predict whether or not a tsunami will strike. Tsunami also means harbor wave in japanese and is commonly referred to as a tidal wave. Tsunami waves slow down and pile up higher as they approach land. Earthquakes, volcanic eruptions and alternative underwater explosions including detonations of.
Understanding how tsunamis form after an earthquake helps scientists predict. A tsunami can kill or injure people and damage or destroy buildings and infrastructure as waves come in and go out. The term tsunami originates from japanese and literally means harbor wave. Remember, tsunamis are an aftereffect of an earthquake. All are the result of violent events with enough power to displace large volumes very rapidly. What causes tsunami indian ocean tsunami information center. Often a tsunami wave warns of its arrival with roaring and rumbling from the ocean, but. It is based on hawaii and was designed to predict tsunamis around the north pacific.
Tsunamis can also result from the impact of a meteor or comet in a body of water. Levin encyclopedia of life support systems eolss continues to be its strict teacher. If a tsunami strikes a coastal area, it can cause death or serious injury to people and damage to buildings. Most of these tsunami are generated by earthquakes that cause displacement of the seafloor, but, as we shall see, tsunami can be generated by volcanic eruptions, landslides, underwater explosions, and meteorite impacts. Partly because of these data limitations, 15 of 20 tsunami warnings issued since 1946 were considered false alarms because the tsunami that arrived was too weak to cause damage. Tsunami impactsintroductiona tsunami can be described as a series of long, powerful ocean waves produced by a disturbance at or close to the ocean.
In this paper, the causes and mechanisms of tsunami generation, theory of wave. Earthquakes, volcanic eruptions and other underwater explosions including detonations, landslides, glacier calvings, meteorite. A tsunami is a series of waves caused by an earthquake, underwater volcanic eruption, landslide or other abrupt disturbance. When this happens, the overriding plate snaps back into an unrestrained position. A tsunami is a devastating natural phenomena that often strikes without warning. Tsunamis are often caused by earthquakes as was demonstrated by the earthquake and subsequent tsunami in japan in march 2011. Oct 02, 2018 debris litters wina beach in palu, sulawesi, four days after the earthquake and tsunami.
What caused the indonesia tsunami and could lives have been. The 1964 alaska tsunami led to 110 deaths, some as far away as crescent city, calif. A tsunami is a series of enormous waves created by an underwater disturbance usually associated with earthquakes occurring below or near the ocean. Tsunamis travel across the open ocean at great speeds and build into large deadly waves in the shallow. Tsunami heads inland destroying everything in its path. It cannot be stopped and when a tsunami is formed, earth.
As the tsunami nears land it slows, but is squeezed upwards increasing in height 4. A tsunami is a series of ocean waves with very long wavelengths typically hundreds of kilometres caused by largescale disturbances of the ocean. Tsunamis and tidal waves are both sea waves, but they have different causes and characteristics. Tsunamis are caused by sudden movements of the earth that happens under the sea. The energy transfer formulates the tsunami, but the size depends on the water levels, since tsunamis travel faster in deeper waters. A tsunami is a series of enormous ocean waves caused by earthquakes, underwater landslides, volcanic eruptions, or asteroids. The source of the plant is known that 90% of the tsunami is caused by tectonic earthquake activity, 9% due to volcanic activity and 1% by soil landslides that occurring in water such as in the lakes or in the ocean or landslides that came from land which is enters to the ocean. Can cause major damage to poorly constructed buildings over small regions. The deadliest tsunami in recorded history occurred in the indian ocean in december 2004. These walls of water can cause widespread destruction when. Effects of tsunami on the environment range from death, destruction, injury, flooding, financial loss, environmental contamination, pollution, and longterm psychological issues to the people in the regions. Cyclones can cause strong winds which can damage trees and communication networks. During the persian siege of the sea town potidaea, greece, herodotus reports how persian attackers who tried to exploit an unusual retreat of the water were suddenly surprised by a great floodtide, higher, as the people of the place.
Jun 06, 2018 the most common cause of a tsunami is fro earthquakes. This video shows what causes tsunamis and the importance of evacuating any area under a tsunami alert. Difference between cyclone and tsunami difference between. They most frequently stem from underwater earthquakes, which cause a change in the ocean floor that impacts the surface water for miles around. Because of the way the seas flow the wave created moves out from the site of the. Date location main article primary cause description 479 bc. Mar 10, 2011 a tsunami is a series of large waves generated by an abrupt movement on the ocean floor that can result from an earthquake, an underwater landslide, a volcanic eruption or very rarely a large. The deeper the water, the greater the speed of tsunami waves will be. A tsunami soonahmee is one of the worlds most powerful and destructive natural forces.
If the trough of the tsunami wave reaches the coast first, this causes a phenomenon called drawdown, where it appears that sea level has dropped considerably. The movie is a dramatization of a real event that shocked the entire world. Join national geographic kids and dive into our tsunami facts to find out. The tsunami devastated the islands and coasts of more than 10 countries in southern asia and eastern africa.
Tsunamis can travel in deep waters at hundreds of miles per hour. Causes, consequences, prediction, and response boris w. A tsunami is a natural hazard consisting of a series of long, surgelike waves generated when a large volume of ocean water is rapidly displaced. And the push of saltwater into freshwater sources nearby can disrupt farming. Often a tsunami wave warns of its arrival with roaring and rumbling from the ocean, but sometimes a rising wall of water approaches silently and imperceptibly.
1096 828 1559 77 62 1118 511 1069 1499 1289 786 426 1505 1109 1018 47 1501 1020 415 954 1171 1359 701 1197 775 109 781 1169 106 138 451 1062 317 825 821 753 841 1204 1421 194 969 1103 1179 761 621 1136