- Wind erosion
- Wind deposition
- Preventing wind erosion
- Explain how wind causes erosion.
- Describe sediments deposited by wind.
- Identify ways to prevent wind erosion.
loess: type of deposit that forms when wind drops layers of silt and clay in nearly vertical cliffs
sand dune: small hill of sand deposited by wind in a region with abundant sand and wind
Introducing the Lesson
Introduce wind erosion with a video of Arches National Park in Utah (see URL below). Challenge students to guess how the beautiful rock sculptures formed. Tell they them will learn how when they read this lesson.
Demonstrate how the wind moves particles of different sizes by using a hairdryer (no heat) to simulate the wind and blowing it across a small amounts of clay, sand, and pebbles. Ask students to describe what they observe and relate particle size to the way particles are transported by the “wind.”
Help students relate erosion by wind with deposits formed by wind. Have them make a flowchart to show what happens to fine particles of clay and silt from the time they are first picked up by the wind to the time they are deposited as loess many miles away. They can add the flow chart to their science notebook.
Have one or more students who need extra challenges teach the topic of sand dune formation to the rest of the class. Suggest that they use multimedia in their presentation. For example, they might show video clips of a diversity of sand dunes and use diagrams to show how wind and gravity create the characteristic dune shape.
With the activity at the URL below, students can model sand dunes and simulate wind and other factors that affect wind erosion. Extensions to the basic activity allow students to investigate the following questions:
- How does the shape of the dunes affect their erosion?
- How does changing wind direction affect dune erosion?
- How does water influence wind erosion of the dunes?
- How do plants influence dune erosion?
Tell students about the Dust Bowl, which occurred during the 1930s following a prolonged drought in Oklahoma and neighboring states. The land had been plowed but without rain to allow crops to grow, the results were dust storms and soil destruction of disastrous proportions. The "black blizzards" of the Dust Bowl caused great hardships for people and lasting devastation of the land. The Dust Bowl has been called our nation’s worst ecological disaster. Discuss the factors that led to the tremendous wind erosion of the dust bowl and how it might have been prevented. You (or your students) can learn more at these URLs:
Reinforce and Review
Copy and distribute the lesson worksheets in the CK-12 Earth Science for Middle School Workbook. Ask students to complete the worksheets alone or in pairs to reinforce lesson content.
Lesson Review Questions
Have students answer the Review Questions listed at the end of the lesson in the FlexBook® student edition.
Check students’ mastery of the lesson with Lesson 10.3 Quiz in CK-12 Earth Science for Middle School Quizzes and Tests.
Points to Consider
Abrasion is the main way that wind wears away rock. The next lesson explains how glaciers wear away rock. How do you think it happens?
Do you think glaciers might cause abrasion, like the wind?