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Extreme Ice

Classroom Activity


Activity Summary
Students investigate how scientists monitor changes in Earth's glaciers, ice caps, and ice sheets.

Learning Objectives
Students will be able to:

  • explain how glaciers are formed.

  • describe different methods scientists use to track glacial change.

Materials

Multimedia Resources

Background
Today, about ten percent of Earth's land surface is covered by ice, in the form of glaciers, ice caps, and ice sheets. These areas of ice grow and shrink in response to changing climate. (Glaciers at the height of the last ice age, some 20,000 years ago, covered much of North America and Europe.)

Most of Earth's ice is found in polar and high-mountain regions. Scientists monitor changes in the ice using a variety of methods, including seasonal mass balance measurements (measuring the mass of water gained or lost each summer at the glacier's surface); area measurements (using GPS data to measure/map the dimensions of individual glaciers and the extent of the regional glacier); ice radar depth measurements (using radar to measure the depth of ice); repeat photography (photographing glaciers over time); velocity measurements (using GPS data to measure glacier velocity), and remote sensing (employing aerial photography and satellite imagery).

Typically, changes to the area and volume of ice occur over long periods of time (hundreds to thousands of years), but recently the rate of glacial melt has been rapidly accelerating. Increased warming over the next century could significantly reduce the size of current ice fields and mountain glaciers—and could even affect the Antarctic Ice Sheets—resulting in higher sea levels.


Procedure

The Lesson

  1. Ask students what they know about glaciers. For example, in which regions of the world might glaciers be found? How are they formed? What are glaciers, exactly? Write all student responses on the board. Then add to the list anything else about glaciers that students would like to know. Direct students to the All About Glaciers Web site. After students have read through the Web feature, revisit the original class responses, correct any misconceptions students had about glaciers, and review which of the students' questions were answered. What did students learn that they found most surprising about glaciers?

  2. Next, have students view the Fastest Glacier video segment, which describes changes to the Jakobshavn glacier in Greenland. As students watch the video, ask them to note the methods scientists are using to track changes in glaciers.

  3. Use the World Glacier Inventory Web Site to review with students the locations of the world's glaciers. (The default settings show glaciers that are 1 to 5 square kilometers in size.) Organize students into teams, and assign each team one of the following ice regions to investigate:

    • Alaska
    • Glacier National Park, Montana
    • Greenland
    • Iceland
    • Polar Ice Caps

  4. Have students use the Internet to find out what research has been done on the ice features (including glaciers, ice caps, and ice sheets) in those areas; and discover what the research has revealed (search terms such as "Alaska glacier research" will bring up relevant information). As teams collect their information, have team members answer the following questions about their assigned region:

    • Which ice feature was researched? How large was it?
    • What data did scientists collect?
    • How did they collect the data? What type(s) of technology or techniques did scientists use?
    • When was the data collected?
    • What conclusions, if any, did the scientists reach regarding the ice feature they studied?

  5. When everyone has finished answering the questions, have teams present their findings to the class. After the presentations, hold a class discussion on the following: What did the research carried out in the various regions have in common? What was different? Were all ice features in all locations retreating? Which areas, if any, exhibited ice loss that concerned scientists? What, if any, possible causes for ice loss did scientists cite?

  6. As an extension, have students research predictions for sea-level rise within the next 100 years. Have each student report what he or she learned, including who made the prediction, what the prediction was based on, and how confident the scientist was in the prediction. After all students have reported, discuss the similarities and differences among the predictions. What might account for differences?



Procedure

Excellent

Satisfactory

Needs Improvement

Tracking Glacial Change

Students create a detailed presentation. They demonstrate a thorough understanding of the method they are presenting, the type of data collected using that method, and what those data reveal about glacial change.

Students create a presentation but lack a clear explanation of the method they are presenting, the type of data collected using that method, and/or what those data reveal about glacial change.

Students create a poorly organized presentation that lacks detail. They cannot clearly articulate the method they are presenting, the type of data collected using that method, and/or what those data reveal about glacial change.


Standards

The "Extreme Ice" activity aligns with the following National Science Education Standards.

Grades 5-8
Earth and Space Science

• Structure of the Earth system
• Earth's history

Science and Technology
• Understanding about science and technology


Grades 9-12
Earth and Space Science

• Energy in the Earth system
• Origin and evolution of the Earth system

Science and Technology
• Understanding about science and technology


Classroom Activity Author

Margy Kuntz has written and edited educational materials for more than 24 years. She has authored numerous educational supplements, basal text materials, and trade books on science, math, and computers.

Teacher's Guide
Extreme Ice
WATCH A PREVIEW BUY THE VIDEO WATCH THE VIDEO ONLINE PROGRAM OVERVIEW CLASSROOM ACTIVITY RELATED NOVA RESOURCES


Interactive All About Glaciers Web Site
Interactive Fastest Glacier QuickTime or Windows Media Video
Interactive World Glacier Inventory Web Site




































ExxonMobil
Koch Foundation
HHMI
CPB
   

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