Describe how they look and how they move. When heated, your drops of food coloring act like convection cells that form near Earth's surface. To see how the Earth's rotation might affect these cells, place the first pie plate into the pie plate containing water and spin it for about 30 seconds. Describe the patterns that are formed. The patterns that formed when you spun the plate can be compared to the wind patterns in Earth's atmosphere.
Wind energy comes of age.
Clues to atmospheric circulation. Science, p. 358. Why the wind blows. Reader's Digest, p. 82. Try your hand at designing and building your own wind vane and anemometer to measure the direction and speed of the wind.