🌍 What is Wind?
Wind is simply air moving from one place to another. But why does the air move? It all comes down to temperature differences!
🔥 Warm-up Activity (5 mins)
Objective: Students will understand that warm air rises and cool air sinks.
Materials: A hot air balloon video (YouTube), a picture of the Earth with sun shining on different parts.
Procedure:
- 🎈 Show a short video of a hot air balloon rising. Ask: Why does it go up? (Warm air inside)
- ☀️ Show the Earth picture. Ask: Where is it hotter? (Equator) Where is it cooler? (Poles)
💨 Main Instruction: Uneven Heating
The Sun heats different parts of the Earth differently. The Equator gets more direct sunlight, so it's warmer. The North and South Poles get less direct sunlight, so they're colder.
- ☀️Uneven Heating: The sun heats the Earth unevenly. Some places get more sunlight and become warmer, while others get less and become cooler.
- ⬆️Warm Air Rises: Warm air is lighter than cool air, so it rises up. Imagine a giant balloon of warm air floating upwards.
- ⬇️Cool Air Sinks: Cool air is heavier than warm air, so it sinks down. It’s like a heavy rock falling to the bottom of a pool.
- ➡️Air Moves In: When warm air rises, cool air moves in to take its place. This moving air is what we call wind!
🌡️ Pressure Differences
This movement creates areas of different air pressure. High pressure means more air is pushing down, and low pressure means less air is pushing down.
- 🌬️ High Pressure: Cool air creates high pressure because it's heavier and sinks.
- 🌀 Low Pressure: Warm air creates low pressure because it's lighter and rises.
- 💨 Wind Direction: Wind always blows from areas of high pressure to areas of low pressure. Think of it like air trying to even things out.
🌬️ Assessment:
Objective: Students can explain how temperature differences cause wind.
Instructions:
- Draw a picture showing the sun heating the Earth unevenly.
- Label the areas of high and low pressure.
- Draw arrows to show which way the wind is blowing.