Tsunami

Question 1

How are tsnami’s formed

Answer 1

When an earthquake occurs beneath the sea bed this can lead to a tsunami

As the sea bed jolts water is displaced and forced upwards creating a wave

As the wave approaches the land they slow and the wavelength becomes compressed

Question 2

What does the earthquake do to the size of the sea

Answer 2

This leads to an increase in wave height: they frequently reach 5-10 meters, but can reach 30 meters

As the wave reaches the shore a vacuum is created and the water recedes rapidly out to sea leaving the sea bed exposed

Question 3

Other causes of tsunami include

Answer 3

Landslides which may be due to earthquakes and volcanic eruptions displacing the water

Underwater volcanic eruptions

Rarely they can be caused by a meteor strike

Question 4

Tsunami usually occur close to plate boundaries and are most common in the area surrounding the Pacific Ocean - ‘Ring of Fire’

Answer 4

YES

Question 5

What is the shoaling effect

Answer 5

As a tsunami nears the land , the front of the wave slows to around 100km/hr and is caught up by the back of the wave still travelling over 800km/hr .

AS A result front wave starts to increase in height to due a process called amplification

Question 6

characteristics tsunami

Answer 6

150-1000km wave length

0.5-5m amplitude

fast velocities up to 600 kph in deep water