Tsunamis vary hugely in size. A tsunami wave that travels to shore may be as little as 15cm in height when it hits. On the other hand, some tsunamis reach many metres in height, as in the case of the world's highest recorded tsunami.
The tallest tsunami ever recorded was at Lituya Bay, Alaska on 9 July 1958, when the biggest of a series of tsunami waves reached a height of 524 metres, or over half a kilometre, the equivalent of 1,720 feet.
Tsunamis can range from 4 to 100 feet tall. It's not the height of the wave itself that classifies if it is a tsunami or not. What classifies a tsunami, is it isn't a natural wave caused by the pull of the moon/sun. It is a large force of energy traveling in through the ocean at over 560 miles per hour. They are caused by landslides, underwater volcanoes, and like in Japan, underwater earthquakes caused by a subducting plate on the earths crust. The one in Japan was 23 feet tall.
if there are earthquakes before the tsunami above 6.5 in the Richter scale. But tsunamis are like a wall of water and big waves are the usual waves (in a bigger scale) you find in the beach
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The size of the wave is not what determines whether the wave is classified as a tsunami.
If it's a tsunami, then it's a tsunami. Some are huge. Some are not.
Here are some reasons why:
The tsunami wave is unlike normal waves in that is NOT caused by wind or tidal action, but instead is a wave caused by seismic movement, volcanic activity, a landslide, a meteor-impact, or even a man-made explosion.
In the case of seismically formed tsunamis, the displacement of the entire water-column (from sea-floor to surface) above the disturbance, is what generates the wave. The wave involves an incredibly enormous amount of water. But interestingly, the wave itself, upon reaching the shore, may be very small. Tiny, even.
Essentially, to the observer on the shore, a tsunami looks like the level of the entire ocean rises rapidly, almost like being in an empty swimming pool and having it filled very rapidly. This wave at the shore can be monstrously huge and very high if the ocean-floor displacement that caused the wave was very large and the underwater topography near the shore is correct. (water that gets very gradually shallower as it nears shore can produce tall tsunamis)
But, if the seismic displacement is small, or the water near shore stays very deep until just offshore, (like some volcanic islands) the wave (height) may small enough to not be noticed unless you were paying close attention. It's still a tsunami. It still involved that whole water column above the displacement on the sea-floor, but it just isn't very big, or at least doesn't look very big.
Distance from the point-of-origin of the tsunami is another factor in the wave size. Some of the most gigantic and destructive tsunamis in history ended up being very tiny a half world away. In addition, the bigger they are the farther they go. (or can be recorded to go) One particular tsunami was measured at 1/2 inch high, thousands of miles away from where it was a giant killer wave, but a 1/2 inch tsunami is still a tsunami.
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The attenuation quoted in the last sentence suggests they diminish with distance by, approximately, the normal inverse-square law, although an individual wave will be affected considerably by its surroundings.
A tsunami can reach only 3 feet but can still cause a huge amount of damage but if your looking for the tidal type at least over 50 feet the one that happened in tiland 2004 was 1 foot over the limit and acturly caused more damage just because of 1 foot if it was 50 it would of caused 6 % less of damage!
There is no size requirement for a tsunami. Any ocean wave or series of waves produced by sea floor displacement could be considered a tsunami.
A tsunami wave is fundamentally different from an ordinary ocean wave.
Normal ocean waves are the result of wind acting on the surface and it usually only takes a few seconds for one to go by.
Tsunami waves are the result of a displacement of the sea floor such as from an underwater earthquake or landslide. They are much longer than wind-driven waves and typically take 5-10 minutes to pass.
Because they are much longer tsunami waves carry much more water, travel further inland, and cause much more damage than normal waves
The largest was about 1700 feet tall. However, most do not even get half that size
they can get pretty big i don't know
a big wave
A hovercraft is good against a tsunami. It can go faster than a tsunami no matter how big it's waves are.
Not necessarily. A tsunami can also be a series of waves.
It will be different according to how big the tsunami is. There is no simple answer to your question.
A big quake on the ricter scale should be more than 8.2 to trigger a tsunami.
a big wave
A flood is a lot of water. A tsunami is a big wave. A tsunami can cause a flood.
very big :P
there was tsunami because the earthquake had a high magnitude,so made big that caused the tsunami
A hovercraft is good against a tsunami. It can go faster than a tsunami no matter how big it's waves are.
Not necessarily. A tsunami can also be a series of waves.
big one that is obviously a good one
It will be different according to how big the tsunami is. There is no simple answer to your question.
Its still called a tsunami. There was a big Tsunami there in 1861/62
A big quake on the ricter scale should be more than 8.2 to trigger a tsunami.
The tsunami in japan was 23-27 feet tall hope this helps
The tsunami that struck Japan was reported from 23-27 feet tall.