--- title: "Erosion and weathering" description: "Make observations and measurements to provide evidence of the effects of weathering or the rate of erosion by water, ice, wind, or vegetation" canonical: https://lightmysky.com/learn/science/erosion-and-weathering-mt_vAP_A986IQ source: https://lightmysky.com/learn/science/erosion-and-weathering-mt_vAP_A986IQ.md retrieved: 2026-11-12 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Erosion and weathering Make observations and measurements to provide evidence of the effects of weathering or the rate of erosion by water, ice, wind, or vegetation Subject: Science · Area: Earth's Systems · Ages 9 to 10 Page: https://lightmysky.com/learn/science/erosion-and-weathering-mt_vAP_A986IQ ## Ready when they can - Define weathering (breaking down of rock in place) and erosion (movement of broken rock/soil) - Describe the effects of at least three agents of weathering/erosion: water, ice, wind, vegetation - Provide evidence from observations showing how weathering or erosion has changed a landscape ## Lesson: How weathering and erosion change the land Weathering breaks rock down where it is. Erosion moves rock pieces or soil away. Water, wind, moving ice and gravity can transport material. Breaking and moving are different actions, though the processes often work together. *(drawing: The rock breaks into pieces that stay where they formed.)* **Example.** Use dated photos or measurements supplied by adults. Outdoor observations must be adult-supervised from a safe place away from water, bank edges and cliffs. Never approach an edge to measure it. A retreating bank shows material was removed. Observed soil transport identifies erosion; widening rock cracks show weathering. Loose rocks alone do not reveal how they broke or moved. Water can enter a crack and freeze. The ice expands and can widen the crack. Wind-blown sand can wear a rock surface away. Growing roots can push cracks wider. These are weathering examples. Flowing water, wind and moving glaciers can also carry loose material away. *(drawing: At one marked point, the surface dropped 1 cm, then 2 cm more, then 4 cm more.)* **Example.** To find the total surface drop at that point, add the separate drops: 1 + 2 + 4 = 7 cm. Do not add readings that already include earlier drops. A lower surface can have other causes, such as soil being pressed down, so also look for evidence of transport. Record the change and time taken. Erosion can be rapid during a storm or gradual over many years. To check whether a bank has retreated, choose adult-supplied photos of the same bank from the same viewpoint on two dates. Matching the bank and viewpoint helps you compare its position rather than differences between places or camera views. One photo shows only one time. **Recap.** Weathering breaks rock down; erosion moves material. Use observations and repeatable measurements to explain what changed and how long it took. *The lesson, questions and flashcards were written for this dataset.* ## Practice 8 questions on this page, each with its working shown. ## Optional connections - [Types of rocks](https://lightmysky.com/learn/science/types-of-rocks-mt_bqL8DD1SbV) - [Properties of rocks](https://lightmysky.com/learn/science/properties-of-rocks-mt_R6YoRXkRxS) ## Opens up - [Finding patterns in data](https://lightmysky.com/learn/science/finding-patterns-in-data-mt_-G6erQvLig) - [What the Ice Left Behind](https://lightmysky.com/learn/geography/what-the-ice-left-behind-mt_D-aB1k0K73) - [Coasts on the Move](https://lightmysky.com/learn/geography/coasts-on-the-move-mt_IVnXDRpfqE) - [Preventing erosion](https://lightmysky.com/learn/science/preventing-erosion-mt_m6UaSmrQVG) - [Weathering, Erosion and How Soil Forms](https://lightmysky.com/learn/science/weathering-erosion-and-how-soil-forms-mt_nQOPOt1VTH) - [How a River Shapes Its Valley](https://lightmysky.com/learn/geography/how-a-river-shapes-its-valley-mt_v6D9mgcf0P) - [How Rocks Change Over Time](https://lightmysky.com/learn/science/how-rocks-change-over-time-mt_z7AJZapsJj)