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Magnetic Storm
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Viewing Ideas
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Before Watching
Demonstrate how magnetism is a property that can be changed. Drag a paper clip along a bar magnet 15 times so that the paper clip becomes magnetized. Use this paper clip to pick up another paper clip. Then, bang the magnetized paper clip on the table. Now try to pick up the other paper clip again. (See Activity Answer on page 3 for an explanation of this concept.) Discuss with your students the difference between the geographic North Pole and the magnetic North Pole. (The geographic North Pole is the point at 90 degrees North latitude. The magnetic North Pole is where the magnetic field lines are vertical and enter Earth, presently at about 82 degrees North latitude and 112 degrees West longitude.)
After Watching
Have a class discussion on how the weakening and shifting magnetic field may affect life on Earth. (With a weakened magnetic field, more radiation would enter Earth's atmosphere resulting in increased deaths from cancer.) Discuss with students how Earth changes over time. The magnetic field is not the only thing that changes. Ask them to think of other examples of change. (Oceans have become mountains, the average global temperature has fluctuated, and the amount of carbon dioxide in the atmosphere has changed.)
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