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Polar Science Assessment Probes
1
Melting Icebergs
Tanya and Stephanie are watching television
when they see a commerical that says the
Earth’s climate is getting warmer. They have
been learning about Antarctica and wonder
what will happen as the icebergs around
Antarctica melt.
Icebergs in McMurdo Sound, off the coast of Antarctica. Photo
courtesy of Kris Kuenning, National Science Foundation.
Tanya: I think the melting icebergs will make ocean levels rise.
Stephanie: I think the melting icebergs won’t change ocean levels.
Which student do you most agree with and why? Explain your thinking.
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Issue 15: Icebergs and Glaciers (August 2009)
Copyright 2009: Ohio State University. Funded by the National Science Foundation. Licensed under a Creative
Commons Attribution-Share Alike 3.0 Unported License.
Polar Science Assessment Probes
2
Melting Icebergs
Teacher Notes
Purpose
The purpose of this assessment probe is to elicit student ideas about melting icebergs. The probe
is designed to determine if students think that melting icebergs will cause sea level rise.
Related Concepts
buoyancy, properties of matter, states and changes of matter, climate change
Explanation
The best answer is Stephanie’s. Melting icebergs and sea ice will not raise sea level because the
ice is already floating (and thus displacing its volume). Only land-based ice (such as glaciers and
ice sheets) can raise sea level.
Curricular and Instructional Considerations
Teachers need to take care when discussing issues like climate change with young students.
Students can become overwhelmed and distressed by these types of issues. This probe may be
best used with students in upper elementary grades and above.
However, elementary teachers may still want students to understand that melting ice does not
raise water levels if it is already floating. A simple activity with ice cubes can allow teachers to
assess student ideas and teach science concepts. See Suggestions for Instruction and Assessment
for more information.
Administering the Probe
Teachers may choose to administer the probe orally or in one-on-one interviews with students. It
may be helpful to show students pictures of icebergs of various sizes before administering the
probe.
Related Ideas in National Science Education Standards (NRC 1996)
K-4 Properties of Objects and Materials
Materials can exist in different states – solid, liquid, and gas. Some common materials,
such as water, can be changed from one state to another by heating or cooling.
K-4 Changes in Environments
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Issue 15: Icebergs and Glaciers (August 2009)
Copyright 2009: Ohio State University. Funded by the National Science Foundation. Licensed under a Creative
Commons Attribution-Share Alike 3.0 Unported License.
Polar Science Assessment Probes
3
Melting Icebergs
Changes in environments can be natural or influenced by humans. Some changes are
good, some are bad, and some are neither good nor bad.
5-8 Structure of the Earth System
Water, which covers the majority of the earth’s surface, circulates through the crust,
oceans, and atmosphere in what is known as the “water cycle.” Water evaporates from
the earth’s surface, rises and cools as it moves to higher elevations, condenses as rain or
snow, and falls to the surface where it collects in lakes.
Related Ideas in Benchmarks for Science Literacy (AAAS 1993)
K-2 The Earth
Water can be a liquid or a solid and can go back and forth from one form to the other. If
water is turned into ice and then the ice is allowed to melt, the amount of water is the
same as it was before freezing.
K-2 Structure of Matter
Objects can be described in terms of the materials they are made of and their physical
properties.
3-5 Structure of Matter
Heating and cooling cause changes in the properties of materials. Many kinds of changes
occur faster under hotter conditions.
Suggestions for Instruction and Assessment
A simple, hands-on activity can supplement or replace the probe entirely. Have students add
water and ice cubes to a container and use a marking pen or piece of tape to mark the water level.
Ask students to predict what will happen to the water level as the ice cubes melt. Allow the ice to
melt (place under a lamp to speed the process) and compare to the original marking. Has the
water level changed?
Teachers of older students may want to more fully connect the probe to the issue of climate
change. The following lessons help students understand the different effects of melting sea ice
and land based ice.
http://beyondpenguins.nsdl.org/
Issue 15: Icebergs and Glaciers (August 2009)
Copyright 2009: Ohio State University. Funded by the National Science Foundation. Licensed under a Creative
Commons Attribution-Share Alike 3.0 Unported License.
Polar Science Assessment Probes
4
Melting Icebergs
When Floating Ice Melts in the Sea
http://education.arm.gov/teacherslounge/lessons/floatingice.stm
Students use water and ice cubes to model what happens when floating ice melts. Students (and
teachers) will observe that the melting of floating ice, such as icebergs and ice shelves, does not
affect sea level. Challenge your students to modify the experiment to show what happens to land
masses surrounded by water when ice melts.
When Land Ice Melts
http://education.arm.gov/teacherslounge/lessons/landice.stm
Students model the melting of land ice (glaciers and ice sheets) to discover that this type of
melting does affect sea level. Challenge students to think about the block of wood. Does this
effectively model what would happen to the land? What does the water represent? How could
they modify the procedure to investigate what happens to another body of land in the same
ocean?
References
American Association for the Advancement of Science (AAAS). 1993. Benchmarks for science
literacy. New York: Oxford University Press.
Keeley, P., F. Eberle, and L. Farrin. 2005. Uncovering student ideas in science, vol. 1: 25
formative assessment probes. Arlington, VA: NSTA Press.
Keeley, P., F. Eberle, and J. Tugel. 2007. Uncovering student ideas in science, vol. 2: 25 more
formative assessment probes. Arlington, VA: NTSA Press.
Keeley, P., F. Eberle, and C. Dorsey. 2008. Uncovering student ideas in science, vol. 3: Another
25 formative assessment probes. Arlington, VA: NSTA Press.
Keeley, P., and J. Tugel. 2009. Uncovering student ideas in science, vol 4. 25 new formative
assessment probes. Arlington, VA: NSTA Press.
National Research Council (NRC). 1996. National science education standards. Washington,
DC: National Academies Press.
http://beyondpenguins.nsdl.org/
Issue 15: Icebergs and Glaciers (August 2009)
Copyright 2009: Ohio State University. Funded by the National Science Foundation. Licensed under a Creative
Commons Attribution-Share Alike 3.0 Unported License.