Lesson 4: Global wind patterns and convection

Activity 2. Follow the air around highs and lows

This is a kinesthetic activity that shows students the effects of the Coriolis Force on winds around high and low-pressure systems. It helps students understand that in the Northern Hemisphere, high-pressure systems rotate in a clockwise direction and that low-pressure systems rotate in a counterclockwise direction.

Online Resource:

• Kinesthetic Activity Support Document
• Blank map of the United States: http://www.teachingboxes.org/catalog.jsp?id=TBOXR-000-000-000-042
• Animations of horizontal and vertical motions: http://www.teachingboxes.org/catalog.jsp?id=COMET-6

Advanced Preparation:

• Read through and try the activity in the Kinesthetic Activity Support Document before class
• Make two copies of the blank map of the United States for each student
• Prepare computer with internet connection and projector to show: Animations of horizontal and vertical motions: http://www.teachingboxes.org/catalog.jsp?id=COMET-6

Time needed: Teacher preparation - 10 minutes; Class activity - 45 minutes

Procedure:
The Kinesthetic Activity Support Document provides step-by-step directions for completing the hand motions for the kinesthetic portion of the activity and explains why rotations are opposite for high and low-pressure systems even though both are due to the Coriolis Effect.

1. Tell students that they will do a hands-on activity that helps them remember the movements of winds around high and low-pressure systems in the Northern Hemisphere.
2. Hand out two copies of blank map of the United States to each student and have them write an 'H' on one map and an 'L' on the second map. (This activity also works well in student pairs where one does the high pressure and one does the low pressure).
3. Follow the instructions to complete the kinesthetic activity.

Closing the activity: After the activity (or as an alternative), show the simple animations of horizontal and vertical motions in atmospheric high and low pressure systems at http://www.teachingboxes.org/catalog.jsp?id=COMET-6. The site also has great explanations of the key concepts of pressure gradients, isobars on weather maps, and the strength of the wind.

Closing the unit:

Explain that by now, everyone should know that air moves and what causes it to move. Discuss the concepts before moving on to the next unit, Counting on Clouds.(The existence of air masses with different temperature, density, and pressure.)

Ask those who are wearing glasses to remove them and breathe on them. What happens. (They get misty.) Not only is water in your breath, it’s also a major component of air. What form is the water is in. (Water vapor) What happens as that water vapor cools and condenses? (It rains!) But what do we see in the sky before the rains begin? (Clouds)

We’ll continue studying weather by exploring clouds.