Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS

 
      Glacier Maker

Instructional Objectives
Background Material
Activity
Procedure
Evaluation
Web Resources


Topic: The Science of Glaciers

Instructional Objectives: Students will:

1. Identify the contents of a glacier like those found in Patagonia.
2. Construct a mini glacier model in class.
3. Compare and contrast the classroom model with Patagonian glaciers.

Background material:

Glaciers are very large moving masses of ice. The contents of a glacier include water and all sizes of sediment (boulders, cobbles pebbles, sand, silt and clay). They move very slowly. There are several types of glaciers such as the Outlet valley glacier, a Cirque glacier, and Alpine valley glacier and a Piedmont glacier.

Glaciers form in mountains and move down mountain valleys until they melt. The ice cracks during this movement down the valley . These cracks are called crevasses. Glaciers that are found in valleys and flow down old or current river valleys and move via gravity are called Outlet valley glaciers. Much smaller glaciers that form in high mountains and then flow down to the valley are called Cirque glaciers. Alpine glaciers are where several Cirque glaciers meet. Piedmond glaciers are very wide and form were valley glaciers join when they emerge from mountains.

(Source: Farndon, John, Dictionary of the Earth, Dorling Kindersley, London, New York, 1994)

Activity: Glacier Maker

Materials Needed:
-Clear Flexible Containers such as plastic shoeboxes, one for each group of four students
-One half quart of gravel and one half quart of dirt for each group of four students
-A few drops of blue food coloring to add to the dirt, gravel, and water mixture
-Sufficient water to fill the plastic shoebox one inch from the top after gravel and dirt have been added (This allows for expansion after freezing)
-Student science journals
-Heated cookie tin so that glaciers can melt
-Freezer space
-Screwdriver or other chipping tool
-Safety glasses for each student
-Drawing paper and stick on labels

Procedure:

Have students work in cooperative groups of 3-4 students.

1. Place gravel and dirt in plastic shoe box and add water and food coloring one inch from top of the container. Mix the contents of the container. You may want to try layers so that the gravel is on the bottom and dirt on the top.

2. Freeze contents of plastic shoebox one or two days to be sure glacier material is frozen.

3. Observe and record observations of the glacier material in science journals.

4. Place frozen glacier on hot cookie tin and observe melting.

5. Use chipping tool with safety glasses to model the cracking of glaciers (calving) in The Living Edens "Patagonia" program. Reflect on this activity in student science journals.

6. Have students hold the frozen glacier material and reflect on unusual density of the glacier and record in student science journals.

7. Have students draw the glacier they created and label the specific parts of a glacier. Use terms as crevasses, end moraine, zone of ablation and zone of accumulation.

Evaluation/Alternative Assessment:

Students will describe the contents of the glacier material. Students will read their student science journal entries in class. Be sure they reflect on the density of the glacier. Students will display the sketch of their glacier .

Elementary Extension:

Students will name glaciers and write a story about how the glacier was named. Students will then read the stories to the class. Establish a rubric for evaluation including the name and the relationship of the name to the story.

High School Extension:

Research glaciers on the world wide web and assign specific glaciers to students on which to collect data. Compare and contrast different glaciers found in Argentina or if data is unavailable, use glaciers in Alaska.

Web Resources:

NOVA: Life Cycle of a Glacier
http://www.pbs.org/wgbh/nova/vinson/glacier.html

All About Glaciers: National Snow and Ice Data Center
http://nsidc.org/glaciers/