Why do tsunamis happen for kids

They can remove sand from beaches , destroy trees , toss and drag vehicles , houses and even destroy whole towns. Tsunamis can even be caused when a meteorite strikes the earth's surface, though it is very rare. A tsunami normally occurs in the Pacific Ocean, especially in what is called the ring of fire , but can occur in any large body of water. The water often draws back from the seacoast half of the wave period prior to the wave getting to the coast.

If the slope of the coast is not steep, the water may pull back for hundreds of meters. People who do not know of the danger often remain at the shore. Tsunamis cannot be prevented. However, there are ways to help stop people dying from a tsunami.

International and regional warning systems, especially for the Pacific Ocean , issue alerts before the big waves reach the shore. Because the earthquake that caused the tsunami can be felt before the wave gets to the shore, people can be warned to go somewhere safe. Tsunamis are often called tidal waves because they usually rise and fall more slowly than ordinary ocean surface waves.

This name is misleading, because tsunamis are not related to tides ; they merely rise slowly as a series of fast-moving waves in the ocean caused by powerful earthquakes or volcanic eruptions. The deadliest tsunami recorded in documented history was on 26 December , and is known as the Indian Ocean Tsunami. It was caused by an earthquake. The earthquake was said to have a magnitude of 9. It was centered in the ocean near the coast of Sumatra , Indonesia. Also, wind-generated waves break as they shoal and lose energy offshore.

Tsunamis act more like a flooding wave. A twenty foot tsunami is a twenty foot rise in sea level. Tsunamis may be accompanied by loud, booming noises. Can earthquakes and tsunamis be predicted? No, earthquakes cannot be predicted. Once an earthquake has occurred, the arrival time of a tsunami, if generated, can be determined accurately.

There is not normally enough time to accurately predict tsunami heights near the source. Away from the source, tsunami wave heights can be estimated based on mathematical tsunami models and observed wave heights. Aerial video of the tsunami that devastated Japan on March 11, Click Here to see an animation of an earthquake and the resulting tsunami. The initial warning is typically based solely on seismic information. After the tsunami is recorded on sea level gages, the warning will be cancelled, restricted, expanded, or downgraded to an advisory.

Warnings indicate that flooding up to the maximum expected limit is possible and residents should follow their local emergency management instructions. Warnings are issued when the earthquake information or tsunami forecasts indicate that a wave over 1 meter in amplitude is expected, possible, or ongoing.

Large inundations are not expected in areas under advisory status. Advisories will be cancelled, extended, or upgraded to a warning depending on the event severity. Advisories are issued when the tsunami forecast is in the range of 0. They can speed across the ocean as fast as a jet plane, swallow up islands and wipe out villages.

But what causes tsuamis…? Join National Geographic Kids and dive into our tsunami facts to find out! About four out of five tsunamis happen within the Ring Of Fire , a zone in the Pacific Ocean where earthquakes and volcanic eruptions frequently take place. Sometimes, though, the plates get stuck, the pressure builds up and they suddenly slam into a new position.

This causes an earthquake. If an earthquake lifts or drops part of the ocean floor, the water above rises and starts spreading across the ocean, causing a tsunami. This causes a build-up of pressure from the magma — which is molten rock and gas — squeezing up between the plates and then rising to the surface.

This eventually resuls in an explosion. This causes the earth to shake. They seem to have been around for some time and go back as far as BC in the North Atlantic Ocean. There was another one in Greece in BC which caused a lot of damage to the civilization on Crete at the time. Tsunamis are not like normal tidal waves and the water from them flows straight and with unbelievable power.

Typical waves are where the water flows in circles. This might amaze you…they can travel at speeds of up to miles kilometres per hour without losing energy as they go along.