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Glaciers & Climate Change. Kristen Tjostheim. Who, What, Why?. The audience: grade 8 challenge class, accustomed to fast paced lectures and group projects Basis of first third of lesson is from MT notes The topic: glaciers and icecaps Seen primarily as a source of freshwater
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Glaciers & Climate Change Kristen Tjostheim
Who, What, Why? • The audience: grade 8 challenge class, accustomed to fast paced lectures and group projects • Basis of first third of lesson is from MT notes • The topic: glaciers and icecaps • Seen primarily as a source of freshwater • The text refers to impacts on ice ages and mentions ice cores • MT had a video about retreating glaciers • My connection: glaciers and icecaps as indicators • Retreating glaciers: current indicators • Ice cores: past indicators
Alberta POS Objectives Also mine
Objective 1 • Students will identify evidence of glacial action, and analyze factors affecting the growth and attrition of glaciers and polar icecaps (Unit E STS Specific Outcome 2.4, p.48) • Discussion about how glaciers affect the land • Video about retreating glaciers
Objective 2 • Students will interpret patterns and trends in data, and infer and explain relationships among the variables (Unit E Analyzing and Interpreting Specific Outcome 1.3, p.49) • Climate Trends Learning Tool
Objective 3 • Students will show interest in science-related questions and issues, and pursue personal interests and career possibilities within science-related fields (Unit E Interest in Science Specific Outcome 1, p.50) • Ice Core Extraction and Analysis • Climate Trends Learning Tool
Lesson Overview 5-minute version
Glaciers • Many watersheds are fed upstream by glaciers in a mountain range. Glaciers are large moving bodies of ice. • Glaciers that cover vast areas of land are called continental glaciers or icecaps. They form in Earth’s coldest regions. Antarctica and Greenland are covered by continental glaciers.
Glaciers also form high up in mountain ranges. Here the temperature is so cold that snow and ice melt very little. More and more snow and ice build up and begin to move. These glaciers, called valley glaciers, flow down through the high valleys between mountain peaks.
Although glaciers are always flowing downhill due to the force of gravity, they can appear to advance, retreat, or remain stationary based on the amount of snowfall and temperature. Advancing Glacier – when it is colder, glacial build-up due to snowfall is greater than melting Retreating Glacier – when it is warmer, melting is greater than the rate of build-up Stationary Glacier – Rate of glacial build-up is equal to the melting
Can glaciers affect the land? Due to their immense size and weight, glaciers can have a huge impact on the shape of the land through weathering, erosion and even deposition as they move over the land. As they melt, the moving water can shape of the land.
Before After
In the past, glaciers covered much larger areas of land during cold periods called ice ages (Earth's climate continually cycles through warm and cold periods). Sometimes glaciers are capable of picking up massive boulders from mountain ranges and moving them down onto the surrounding plains. When the glacier finally retreats during a warmer phase of Earth's climate cycles, these huge boulders called erratics get left behind in places like the prairies where they seem very out of place!
Describe at least four different ways that glaciers shape the land through erosion or deposition. Don't worry about what those landforms are called, just describe them.
Global warming and glacial retreat. http://www.videos.bild-art.de/glaciers.htm http://www.explainingclimatechange.ca/Climate%20Change%201-8/swf/icecore/IceCoreResearch.swf http://www.explainingclimatechange.ca/Climate%20Change%201-8/swf/climatetrends/historyGraphs.swf
Aesthetics How is this lesson imaginative?
Aesthetics • Story • Intro • Presented by data • Defamiliarization • Retreating Glaciers, Erratics • Ice cores • Fill in the blank! • Letting students make inferences, notice connections, explain phenomena