Melting Glaciers
Goal
Students learn that alpine glaciers are shrinking due to warmer atmospheric temperatures associated with climate change
Engage students with photos showing how Alaskan glaciers have changed over time.
- Glaciers Then and Now: In this activity students compare photographs of glaciers to observe how Alaskan glaciers have changed over the last century.
Explore how glaciers move, grow, and shrink using a mathematical model and a physical model.
- PhET Glacier Interactive: With this mathematical model, students can explore the impact of mountain snowfall and temperature on the size of a glacier.
- Model a Moving Glacier: Use this physical model to explore how glacial ice flows over time. Experimenting with warming the model ice, changing the surface texture, and simulating melt water on the base of the glacier, students can investigate how different factors impact the rate of ice movement.
- After students have explored both models, ask what each model describes about glaciers. Ask students how each model is, or is not, like a real glacier, and how each model can be used to understand how glaciers will behave with warmer atmospheric temperatures. You may wish to do this as a class discussion, or have groups of students discuss and make a poster or presentation slide that compares the two models.
Evaluate student learning by having students describe reasons for changes in glaciers.
- Have students look again at the pairs of photos in Glaciers: Then and Now and describe what factors might have caused the changes in Alaskan glaciers they see. Students' answers should mention that gradually warming temperatures, less snowfall, or a combination of those two has led to less glacier ice.