Changes to the Earth’s Surface A Look at How Landforms are the Result of Changes to Earth’s Surface by Water, Wind, and Ice

What is a Landform? In your science notebook, write a description of how you would describe a landform to another student. Although there are many different landforms, in this lesson, we will focus on three specific landforms.

Canyons Photo credits: Matakatamiba Canyon; http://office.microsoft.com Bighorn Canyon; http://office.microsoft.com Grand Canyon; http://office.microsoft.com

Sand Dunes Photo credits: Gobi Desert; http://office.microsoft.com Sahara Desert; http://office.microsoft.com Coastline, Lighthouse; http://office.microsoft.com Monahans; Wiki-commons

River Deltas Mississippi River Delta - Shows its characteristic bird's-foot pattern and plumes of sediment entering the ocean from the multiple mouths of the Mississippi River. The lower picture is of the Nile River Delta. Pictures courtesy Wiki-commons.

Weathering, Erosion, and Deposition by Wind Sand dunes form by… The upper picture shows dunes that are formed and changed by wind. The lower picture shows dunes that are created and changed by wind as well. Students may observe that the sand along the coast may also be moved by waves (water). Upper left photo: dunes near Monahans, Texas (Photo: Monahans: Wiki-commons) Lower right photo: Port Aransas, Texas. (Photo: A. Venegas) Sand dunes change by…

Weathering, Erosion, and Deposition by Wind The wind reshapes the rock by… Upper photo: Arches National Park, Utah (photo: Arches National Park; http://office.microsoft.com) Lower photo: Chihuahuan Desert, Big Bend, Texas (photo: Wiki-commons)

Weathering, Erosion, and Deposition by Water Flowing water changes the rock by… Upper photo: Niagara River, Canada (Photo: A. Venegas) Lower photo: Whirlpool Rapids Bridge (Photo: Wikimedia Commons)

Weathering, Erosion, and Deposition by Water Upper photo: Active gully erosion to the west of Broadford, Australia, after recent heavy rains (Photo: http://www.dpi.vic.gov.au/agriculture/about-agriculture/newsletters-and-updates/sheep-notes-newsletter/autumn-2011) Lower photo: Fjaðrárgljúfur canyon near Kirkjubaejarklaustur, Iceland (Photo: pjt56; http://en.wikipedia.org/wiki/File:Fjadr%C3%A1rglj%C3%BAfur-pjt.jpg) Canyons change over time by… Canyons form by…

Erosion and Deposition by Water Deltas form by… Upper photo: Atchafalaya River Delta, Louisiana (Photo: Wikimedia Commons) Lower photo: Wax Lake Delta, Louisiana (Photo: Wikimedia Commons) Deltas change over time by…

Weathering, Erosion, and Deposition by Water (Waves) Waves change the rock by… The upper picture shows wave action on a cliff. The landform has changed from a cliff to a sea arch. The lower picture shows the coast in Galveston, Texas that has been eroded by waves. A question to ask students might be: what might be the consequences if wave action continues over time? Upper photo: Wave erosion on a Portland Cliff (Photo: Nigel Chadwick; http://commons.wikimedia.org/wiki/File:Wave_erosion_on_a_Portland_Cliff_-_geograph.org.uk_-_109895.jpg) Lower photo: Beach erosion along Galveston’s beaches. (Photo: FEMA)

Weathering, Erosion, and Deposition by Water (Waves) Over time, waves can change… Upper photo: Cathedral Cove, New Zealand (Photo: C. Mackenzie) Lower photo: Swanlake Bay wave cut platform (Photo: Sid Howells; http://www.geograph.org.uk/photo/1570744 )

Erosional/Weathering Agent: Ice Upper photo: Hurricane Ridge, Washington (Photo: A. Venegas) Lower photo: Milford, New Zealand, cool green glacial lake in mountaintop (Photo: C. Mackenzie) Ice can change rock by…

Erosional/Weathering Agent: Ice Mountains can be reshaped by… The upper photo shows how a U-shaped valley has been carved in a mountain by ice (glacier). The lower photo shows the reshaping of a mountain through exfoliation. Water has seeped into cracks, and through years of heating and freezing, the layers of rock have cracked and moved down the landform. Upper photo: Alpspitze and Zugspitze mountain (Photo: http://office.microsoft.com) Lower photo: Enchanted Rock (Photo: Wikimedia Commons)

Landforms on Earth Are all Earth’s landforms the same? Why or why not? What are some of the features that you see when you look at the pictures? Do you think that these landforms have always been the same? Do you think that changes in these landforms occurred quickly or did they take a long time to be formed? Are all Earth’s landforms the same? Why or why not? No, Earth has different landforms. Answers may vary on the why responses. What are some of the features that you see when you look at the pictures? Answers may vary. Do you think that these landforms have always been the same? No Do you think that changes on these landforms occurred quickly or did they take a long time to be formed? It took time for these landforms to occur.

Landforms on Earth How will these landforms look: Two days from now, one year from now? Ten years from now? One hundred years from now? One thousand years from now? One million years from now? Which forces caused these landforms to change? How do the landforms that are formed and changed by water, wind, and ice differ from each other? How will these landforms look two days from now? One year from now, ten years from now? Very little noticeable change. One Hundred years from now? Change can begin to be noticeable. One thousand years from now? Most will change in size and shape over many years. One million years from now? There may be large amount of change. What force/action caused these landforms to change? Energy from wind, water, and ice caused the changes. How do the landforms that are formed and changed by water, wind, and ice differ from each other? Yes, canyons and deltas are caused by water, and sand dunes by blowing wind. Ice, in the form of glaciers, can carve rocks or cause them to crack.

Landform Defined In your science notebook, write a definition for the word “landform”. Landform - Any feature on the Earth's surface, caused by erosion, sedimentation, or movement of material by wind, water, or ice Teacher note: Do not click after the first sentence comes in. Allow time for students to write a definition before giving them a formal definition.