PROBLEM: How does nature change the Earth's surface over time in areas where it is extremely cold?

PREDICTION:

PROCEDURE:

EXERCISE 1. Look at the maps on the next two pages. Compare their landscapes.

1. Write the name of the location of each map.

2. Which map has more snow and ice? ____________ How can you tell?
    
3. Which map has more lakes and ponds?
   How can you tell? 
    
4. Which area has been more effected by ice and snow? Explain your answer.

EXERCISE 2.

MATERIALS: 2 trays, sand, 2 small clay slabs, beaker, water and ice cubes

1. Place one slab of clay into a tray. Try to "carve" a landscape in one of the slabs of clay by pouring about 100 ml of water on it.
    
   Is there any way that you can make the water "cut" the clay? Explain your answer.
    
2. Remove the clay from the tray. Take 250 ml of sand and pour it into the tray, making a hill. Pour 100 ml of water on the top of the sand hill. Record what happens.
    
3. Now put the second slab of clay into a tray. Using a piece of ice, try to "carve" a landscape in it. Does the ice cut the clay? Can you actually make a landscape?
    
4. Draw on the back of this paper your top and side views of your ice-carved landscape on the next page.

CONCLUSION: Is water or ice the main agent of erosion in areas where it is extremely cold? What do you think is the major agent of erosion in warm areas?