What is wind?
Wind is air that moves. It’s made up of many different gases like oxygen and nitrogen.
Fast winds that blow for a short time are called gusts.
Strong winds that blow for about one minute are called squalls.
How does wind form?
Wind is formed by the heat of the Sun and the spinning of the Earth. When the Sun shines down on Earth, it heats up the air. Hot air rises but cold air doesn’t.
When the Sun heats up the air and makes it rise, cold air moves in to take the place of the hot air. This movement of air creates wind. As the Earth spins it changes the direction of the wind.
Have you ever noticed that the wind always seems to blow at the beach? That’s because the Sun heats the air above land quicker than the air above water. When the hot air over the land rises, cooler air from the ocean rushes to the shore to take its place. The result is wind that blows towards the shore (sea breeze).
In the evening, it’s the other way around, the land cools down faster than the sea. The air above the ocean rises first and the air above the land takes its place. The result is wind that blows out to sea (land breeze).
The bigger the temperature difference, the faster the wind blows.
How is wind measured?
Meteorologists are people who study the weather. To measure the wind they use direction and speed.
You can find wind vanes on top of many buildings, they are used to measure the direction of the wind.
An instrument called an anemometer is used to measure the speed of the wind. It looks like a pole with cups.
Did you know?
Wind in outer space is called solar wind. It is made up of gases and particles from the Sun.
