A wind vane (figure 5) is used to indicate the direction of wind (the moving air in the atmosphere).
The speed or strength of wind is measured using an anemometer (figure 6) in units of kilometres per hour (km/h).
Being Creative: To feel the movement of air or wind in action,
have a classmate stand by the closed door of your classroom, and then open it quickly. Ask your classmate what they experience/feel.
Key Words
Wind vane Anemometer
Kilometres per hour
Beaufort Scale
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How a Wind Vane Works 5. A wind vane
The wind vane is a free- moving arrow on a high mast.
The tail of the arrow is wide and blown forward by the wind.
This allows the head of the arrow to point in the direction from which the wind is blowing.
According to the arrowhead,
from which direction is the wind blowing?
How an Anemometer Works 6. An anemometer
Three cups rotate when the wind blows. The stronger the wind, the faster they move.
The number of times the cup rotates is used to calculate wind speed. It is recorded and displayed on the meter.
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Measuring and Forecasting Weather
Fun Fact!
The rooster you see on top of the wind vane is just for decoration! They came into fashion in the ninth century when Pope Nicholas ordered that all weather vanes feature them. Can you think of what they might symbolise? Think of what happened at Easter.
