Tsunami Definition Francais

A tsunami occurs when a large body of water is moved. This may be the case of a major earthquake with a magnitude of 6.3 („threshold” according to the available tsunami catalogues: NOA, Novosibirsk catalogue, etc.) or more, when the seabed falls or rises sharply along a fault (see Fig. 1), during a coastal or underwater landslide, during an impact by an asteroid or comet, or during an iceberg reversal. A strong earthquake does not necessarily produce a tsunami: it all depends on how (speed, surface, etc.) the underwater topography (bathymetry) changes around the fault and transfers the deformation to the overlying water column. Landslides and volcanic eruptions can trigger tsunamis in lakes and rivers. [21] Lake Geneva experienced a tsunami in 563, the Tauredunum tsunami, with a wave reaching 13 meters. [22] [23] Tsunamis affected other alpine lakes, including Lake Como in the sixth and twelfth centuries, Lake Lucerne in 1601 and Lake Bourget in 1822.[24] Thus, the tsunami is characterized by a series of waves of long periods between 15 and 60 minutes. Waves that are not very noticeable at first – from a height of a few centimeters to a few tens of centimeters – and that propagate across the ocean at speeds between 500 and 800 kilometers per hour. As the depth of the water decreases as it approaches a continental shelf, its speed slows to a few tens of kilometers per hour. Their amplitude, on the other hand, is increasing. The highest waves can reach about 30 meters. Tsunamis can destroy homes, infrastructure and flora by: Definition of tsunami presented by lalanguefrancaise.com – These definitions of tsunami are for informational purposes only and are taken from royalty-free dictionaries. More information about the word tsunami is provided by the editors of lalanguefrancaise.com These parameters are essentially constant during the propagation of the tsunami, whose energy loss due to friction is low due to its long wavelength.

The Imamura scale makes it possible to assign a magnitude to tsunamis. Introduced by Akitsune Imamura in 1942 and developed by Iida in 1956, it is one of the simplest. The magnitude is calculated from the maximum height of the wave on the coast according to the formula[15]: the victims carried away by a tsunami can receive various shocks from the objects transported (pieces of destroyed houses, boats, cars, trees, etc.) or be violently thrown against terrestrial objects (street furniture, trees, etc.): these blows can be fatal or cause a loss of consciousness and abilities, Losses that lead to drowning. Some victims may also be trapped under the rubble of houses. After all, the low tide of the tsunami is capable of bringing people to the coast, where they drift and die without help from drowning, exhaustion or thirst. Awareness of the phenomenon and its dangers is also a crucial factor in saving lives, as not all coasts have alarm systems – especially the coasts of the Atlantic and Indian Oceans do not. In addition, some tsunamis cannot be detected in time (local tsunamis). The presence of a tsunami warning system that alerts the population a few hours before a tsunami occurs, the awareness of the coastal population of the risks and gestures of survival, as well as the safeguarding of habitat can save most lives.

In French, the term tidal wave was commonly used to refer to tsunamis. However, it is an inaccurate term as it includes tsunamis and other underwater marine phenomena under the same name. Scientists therefore formalized the term „tsunami”[3] in 1963, which is the subject of this article. Tsunamis occur almost every year around the world. The most violent can change the course of history. For example, archaeologists have argued that a tidal wave in the Mediterranean Sea devastated the northern coast of Crete just over 3,500 years ago; This catastrophe would have marked the beginning of the decadence of the Minoan civilization, one of the most refined of antiquity[27]. Some tsunamis can spread thousands of kilometres and reach the entire coast of an ocean in less than a day. These large tsunamis are usually tectonic in origin, as landslides and volcanic explosions usually produce shorter wavelengths that resolve quickly: this is called wave dispersion. Number of points from the word tsunami to Scrabble: 9 points To measure the impact or strength of tsunamis, different scales are used, analogous to the Richter scale for earthquakes. As tsunamis were a major threat to the population, an international warning centre was established in 1965. It collects seismic information from more than 50 stations around the world, and if the location and parameters of an earthquake are likely to trigger a tsunami, affected coastal areas or even a larger region will be alerted. It is not primarily the height of the tsunami that is its destructive power, but the duration of the rise in the water level and the amount of water that moves in the process: when waves of several meters or even ten meters in height are legion on the coasts of the Pacific Ocean, they do not carry enough energy to penetrate deep inland.

We can look at the phenomenon from another angle: a classic wave that lasts no more than a minute does not raise the water level long enough to penetrate deeply, while the water level rises above its normal level for 5 to 30 minutes during the passage of a tsunami. Tsunamis are among the most destructive disasters in history. Over the past four millennia, they have received a total of more than 600,000 victims through at least 279 recorded events[2]. The 2004 Indian Ocean tsunami was the deadliest disaster in 30 years, with more than 250,000 victims. The term tsunami (津波) is a Japanese word derived from tsu (津?), „port”, „ford” and nami (波?), „wave(s)”; It literally means „port wave” or „port wave”. It will be so named by the fishermen who, having noticed nothing unusual off the coast, found their port city devastated. The word untranslatable was first used in English in 1896, in December, by American geographer Eliza Ruhamah Scidmore, who, after a trip to Japan, described in the National Geographic Society the Meiji-Sanriku earthquake of June 15, 1896. Freed by geographers and journalists since 1914, it adopts an s in the plural (tsunamis). The really popular use of this first scientific or limited term dates back to the December 26, 2004 earthquake in the Indian Ocean.