Floods From Tsunamis

Name: _________________________________       Date: _____________

A flood is always a frightening event. The sudden and powerful force of raging water can level a landscape in seconds. But floods triggered by tsunamis from earthquakes are the most terrifying of all. Tsunami waves can travel at speeds of over 500 miles per hour. Waves can arrive with little or no warning or can cause massive destruction.

In this activity, you'll take a closer look at wave data from the tragic Indonesian tsunami of 2004. Then you'll explore satellite views of destruction caused by tsunami-triggered floods.

1. A tsunami's amplitude or height is a pretty good indicator of its potential to do damage. Click this link to see how the amplitude of the waves from the Indonesian tsunami changed as it moved outward from the earthquake's epicenter. The color scale to the right of the image shows the amplitude in centimeters.
   1. What color shows the greatest wave amplitude?
      
      
      
      
   2. About how big is this in centimeters?
      
      
      
      
2. Describe how far the region of highest amplitude stretched geographically.
   
   
   
   
3. Estimate the amplitude of the waves when they reached the following places. (If you're not sure where these countries are, click the link in Question 5 below and scroll down to the map.)
   1. the Horn of Africa (the triangular tip along Africa's northeast coast)
      
      
      
      
   2. the west coast of India
      
      
      
      
   3. Thailand
      
      
      
      
   4. Sri Lanka
      
      
      
      
4. Next, you'll take a look at tsunami arrival times as the waves spread across the Indian Ocean. How long did it take for the tsunami to reach:
   1. the west coast of Indonesia?
      
      
      
      
   2. the east coast of India?
      
      
      
      
   3. the Horn of Africa?
      
      
      
      
5. To see the toll of tsunami-related floods in different parts of the world, look at this tsunami fatality report and map. Make sure you scroll down to see the map. List the four countries that suffered the greatest numbers of casualties from tsunami-related floods, with their totals.
   
   
   
   
6. What conclusions can you draw about the links between wave amplitude, arrival time, and flood death totals from the tsunami? Give examples to support your conclusions.
   
   
   
   
7. You'll now take a look at examples of the devastation caused by floods from the Indonesian tsunami. View these before-and-after satellite images of Meulaboh, Indonesia. What changes do you observe?
   
   
   
   
8. View these images of Indonesia's Aceh Province on December 29, 2004 and on January 2, 2005. For each pair of images, list at least three changes you observe.
   
   
   
   
9. Look at pictures of India, Sri Lanka, and Thailand. What conclusions can you draw about the extent and impact of floods from the tsunami?