Students will:
1. Speculate on the dangers that icecaps might pose on a global scale; describe physical properties of ice.
2. Demonstrate, through a series of experiments, several physical properties of ice (ability to fracture, refreezing to other pieces of ice, melting under raised temperatures, and melting faster under pressure); hypothesize on the outcomes of each experiment; record observations and analyze the results of each experiment; relate experiments to the effects of global warming on icecaps.
3. Relate their in-class lab work to the New York Times article "Under Antarctica, Clues to an Icecap's Fate."

Activities / Procedures:
1. WARM-UP: About 90 percent of the world's ice is contained in a gigantic icecap in Antarctica. What dangers do you think this icecap might pose on a global scale? (Hint: Think about what you know about global warming.) What are some of the physical properties of ice, and how might these properties relate to the possible dangers you have listed?  Write all of the properties of ice mentioned by students on the board, and ask how they know that these properties exist based on their own observations.

2. We will be experimenting with ice in this lesson to better understand the dangers that icecaps pose when the global temperature rises, as it is doing now due to trends in global warming. You and a partner will need a pan containing a hammer, cloth, cup and piece of brick.  Place the contents of your pan on your desks. Then, put three ice cubes in your pan. We will follow the lab procedures below, following each step together as a class.

--Wrap one ice cube in your piece of cloth, and place the wrapped cube in the middle of your desk. Then, use the hammer to carefully break apart the ice cube into small pieces. Open the cloth, and empty the ice pieces into the cup. Now, in your lab journal, hypothesize what you think will happen to the ice pieces after a few minutes and describe the steps of this part of the experiment. After two or three minutes, observe what has happened to the ice pieces, and record your observations in your lab book. (Ice pieces will be frozen together with many holes and tunnels in between them.) Answer these questions in your lab book: What happened when pieces of ice were allowed to touch for a short amount of time in the cup? How might this relate to what happens to icecaps? (When ice caps break apart and then pieces of ice rejoin, crevasses and tunnels form.) What do you suppose these holes between the ice pieces will allow water to do? (Water can flow through the ice, breaking the ice caps down even further and raising the level of the surrounding water, causing the sea level to rise.) Discuss your answers with your classmates.

--Look at what has happened to your other two ice cubes that are still in the pan, and answer the following in your lab book: Why have they melted at the same rate? (The temperature around both of them has remained constant.) What would you expect to happen if a heat lamp were shone upon them, and how would that represent the global warming trend? (The ice would melt faster due to higher temperatures.) What would you expect to happen if you placed the pan on a stove, and how would that represent what happens on Earth? (The ice would melt faster due to increased temperature below the surface of the Earth.) Discuss your answers with your classmates.

--Place the ice cubes at opposite ends of the pan. Write a hypothesis for what you think would happen if you put your piece of brick on top of one of the ice cubes and why. Then, balance your brick on top of one ice cube, and leave the other cube uncovered. In your lab journal, describe the steps of this part of the experiment. Observe and record what is happening to the ice cubes (the ice cube under the pressure of the brick will melt faster than the other ice cube.) After a few minutes, remove the brick and observe and record what has happened to each cube. Answer these questions in your lab book: Why would ice with pressure on it melt faster than ice without this added pressure? Where did melting seem to take place? (On the bottom of the ice cube.) How does this represent how glacier movement occurs? (Water accumulates at the bottom of the "glacier," giving it the ability to move more.) How does the rising melted water level represent the danger of global warming on the world's icecaps? (The sea level rises, causing flooding on a global scale.) Discuss your answers with your classmates.

3. WRAP-UP/HOMEWORK: Students relate their in-class ice lab to the article "Under Antarctica, Clues to an Icecap's Fate" by answering the following questions in their lab books following their experiment notes (written on the board for students to copy prior to leaving class):

Related Article
Under Antarctica, Clues to an Icecap's Fate
By MALCOLM W. BROWNE

(Go to Article.)

a. What would cause "swirls" and "ice streams" in the icecaps in Antarctica, given what you observed in your lab? What are the dangers of these streams? What two "mechanisms" propel these ice streams, and how did you demonstrate these mechanisms in the lab?

b. How has global warming affected the Antarctic icecaps?

c. What ice cap "terrain" was Radarstat able to record, and based on what you know about the properties of ice, how could these features form on an icecap?

d. Why is it "potentially bad news" that "East Antarctica, like West Antarctica, seems to have a mechanism for rapidly moving ice from the interior to the coastal sea"?

e. Why is it "important to measure ice movement in many different places at different times, to gauge overall effects"? Give examples provided in the article.

f. How does Radarstat work, and why is it a significant piece of technology in understanding the effects of global warming?

--How do icecaps form?

--What geologic and environmental events cause the many physical features of icecaps to develop?

--What are the differences between a glacier, an icecap and an iceberg?

--Why are icecaps so often researched to learn about the environment?

--What causes global warming, and what are the effects?

--What can someone your age do to slow the trend in global warming?