Answer to Question 1
ANSWER: A successful answer will list and describe four of the following:
- The jolt and shaking of an earthquake lasting longer than 15 seconds may indicate the occurrence of a large earthquake offshore.
- A sudden rise or drop in sea level may indicate that water is accumulating into a tsunami.
- A loud, roaring noise from offshore may be caused by the sound of the tsunami itself.
- You hear a report of a major earthquake in the Pacific Ocean.
- You see a large landslide into a nearby body of water.
Answer to Question 2
ANSWER: A successful answer will include the cause and effect of at least three of the following:
- if the tsunami enters a bay or river mouth, the height of the wave will increase as the opening narrows
- tsunami waves change direction as they pass over shallow water and affect all sides of an island as a result
- as tsunami waves cross into shallow water they will react with the bottom and slow down, creating shorter waves
- shorter wavelengths in shallow water will result in increased wave height