Which describes the waves formed by tsunamis?
A They cause large waves in the open ocean, but small ones near the shore
B They cause small waves in the open ocean but large ones near the shore
C They cause large waves both in the open ocean and near the shore
D They cause small waves both in the open ocean and near the shore
C They cause large waves both in the open ocean and near the shore
B They cause small waves in the open ocean but large ones near the shore
The correct answer is C) They cause large waves both in the open ocean and near the shore.
Tsunamis are large ocean waves that are usually caused by underwater earthquakes, volcanic eruptions, or landslides. They can also be triggered by other disturbances such as meteorite impacts or the collapse of a volcano into the sea.
Tsunami waves are different from regular ocean waves because of their long wavelengths and periods. This allows them to travel across the ocean at high speeds with very little energy loss. In the open ocean, these waves may appear as a relatively small disturbance on the surface, often going unnoticed by ships or boats.
As the tsunami approaches the coast, the shallowing seabed causes the wave to slow down and the wave height to increase dramatically. This is when the tsunami waves become much more powerful and dangerous. Near the shore, they can reach heights of tens or even hundreds of feet, depending on the specific characteristics of the coastline.
To understand this phenomenon, it is crucial to recognize that a tsunami is not a single wave but a series of waves, known as a wave train. As the tsunami propagates across the ocean, different parts of the wave train may reach different locations at different times, resulting in a series of large waves.
It is important to note that tsunamis can also be accompanied by strong currents and flooding, which can cause further destruction and loss of life. Therefore, it is vital to be aware of tsunami warnings and evacuate to higher ground if necessary.
In summary, tsunamis cause large waves both in the open ocean and near the shore, making them a powerful and destructive force of nature.