2. Erosion Day 1

3. Define the word Erosion in your own words.

4. Earth is Change! The rock that you pass on the way to school each day and the mountains you see in the distance may look like they've been there forever, but the truth is that they are slowly disappearing. Each time it rains and every time the wind blows, tiny pieces of sediment get taken away.

5. Erosion is Change ! This process, known as Erosion, is gradually wearing down the surface of the earth. Erosion is the process by which weathered rock and soil are moved from one place to another. Erosion carves the Earth's surface creating canyons, gorges, and even beaches. What do you think has caused this rock to look this way?

6. Rain causes Erosion When rain falls to the Earth it can evaporate, sink into the ground, or flow over the land as Runoff. When it flows over land, erosion occurs. Runoff picks up pieces of rock and "runs" downhill cutting tiny grooves (called rills) into the land. How much erosion takes place is determined by the: rills amount of rainfall amount of plant growth shape of the land type of rock Can you list 3 things that effect runoff? Can you explain what runoff is?

7. Wind causes Erosion Wind erosion is a major problem on about 75 million acres of land in the United States. About 5 million acres are moderately to severely damaged each year. Wind erosion physically removes from the field the most fertile portion of the soil. Dust obscures visibility and pollutes the air and water, causes automobile accidents, fouls machinery, and imperils animal and human health. How do you think farmers feel about wind erosion?

8. Sand Causes Erosion The most active agent of erosion with sand is wind. As the wind blows it picks up small particles of sand/sediment and blasts large rocks with the abrasive particles, cutting and shaping the rock. The ability for wind to erode larger rocks is controlled by: Size of particles Speed of wind Length of time wind blows Resistance of rocks Describe the circumstances in which sand can cause the most erosion.

9. Waves Cause Erosion Waves cause erosion by four different methods: Breaking – as the breaking waves hit the shoreline, their force knocks off pieces of existing rocks. Forcing water into the cracks of the rocks on the shoreline Abrasion- waves carry small rocks and sand that scrape other rocks Chemical weathering (salt water breaks down the rocks). Compare and contrast chemical weathering to abrasion in wave erosion.

10. Waves Cause Erosion Factors that affect the rate of erosion at the shoreline include: Size of the waves Force of the waves Type of the rock

11. Rain Causes Erosion Wind Causes Erosion Sand Causes Erosion Waves Cause Erosion