Tsunami
Geohazard
How is a tsunami formed?
Tsunamis are usually created from an underwater earthquake at tectonic plate boundaries. when the ocean floor at these boundaries rise or fall it displaces the water above it and cause large rolling waves that will become the tsunami. Tsunamis may also be cause by underwater landslides or volcanic eruptions. They may even be launched by the impact of a meteor plunging into the ocean.
What is a tsunami?
A tsunami is a series of ocean waves that sends surges of water sometimes reaching heights of over 100 feet onto land. These walls of water can cause widespread destruction when they crash ashore. Tsunamis race across the sea at up to 500 miles an hour. At that pace they can cross the entire expanse of the Pacific Ocean in less than a day. And their long wavelengths mean they lose very little energy along the way. A tsunami’s trough, the low point beneath the wave’s crest, often reaches shore first. When it does, it produces a vacuum effect that sucks coastal water seaward and exposes harbor and sea floors. This retreating of sea water is an important warning sign of a tsunami, because the wave’s crest and its enormous volume of water typically hit shore five minutes or so later. Recognizing this phenomenon can save lives. Tsunamis often have a series of large waves instead of just one.
Why they are a concern to us
Tsunamis devastate the places they occur. They kill many people and take peoples homes. We need to develop new technology to find the tsunami before it reaches land to protect the lives of people.
Where tsunamis occur
Tsunamis can occur on any fault line in the world. The Ring of Fire is known to have a lot of tsunamis occur within them. Tsunamis occur there because the Ring of Fire is a string of underwater volcanoes.
How Tsunamis are measured
A tsunami is scaled based on its intensity. Scientists take the magnitude and maximum height to define the intensity of the tsunami. It is noticed that a tsunami has ten percent of energy as the earthquake that caused it.
Japan Tsunami of 2011
This tsunami was not the most devastating of its century but definitely left a lasting impact on many Japanese people. As many as 15,891 people were confirmed to be dead and 2,500 were never found.
Na hour after the underwater earthquake Japan had the first wave. the tsunami waves reached heights of up to 128 feet and traveled six miles inland. The tsunami flooded approximately 217 square mile.
Waves reached other countries also like Chile, Alaska, and Hawaii. There was an estimated 5 million tons of debris carried into the ocean.
Indian Ocean Tsunami 2004
On December 26, 2004, the Indian plate was subducted by the Burma plate causing a series of large tsunamis waves. This devastating tsunami killed 230,000 people in fourteen different countries. Indonesia was the hardest hit country.
The tsunami had waves up to 100 feet high. It was one of the most deadly natural disasters in the world. This tsunami had the third largest earthquake recorded on the seismograph and had the longest duration ever recorded. The tsunami had many aftershocks with magnitudes up to 6.1. This tsunami is currently ranked the seventh largest in the world since the 1900s.
Ways to prepare for a tsunami
There is not much you can do to prevent a tsunami. There are some ways you can prepare. I suggest country's that can donate to a tsunami fund so that when one does strike we have money to use for the rebuilding process. This would save lives because instead of trying to get money together we would have the funds to just go in and start rescuing people and rebuilding. We could also form a tsunami team that is trained to rescue people and have them on call at all times to come in and help when a tsunami does occur. Finally, all country's should make an agreement that if one does occur they will send rescue teams into whatever country and help as much as they can. Since tsunamis are unpredictable we need to focus on helping each other once one does occur.