The greenhouse effect is a natural process that makes life on Earth possible. Like the glass walls of a greenhouse, certain gases in our atmosphere play a crucial role in maintaining Earth's temperature at a comfortable level. Without this natural phenomenon, our planet would be too cold to support life.

The process begins with sunlight reaching Earth's atmosphere. While some of this energy bounces back to space from clouds and Earth's surface, much of it warms our planet. As Earth's surface warms up, it gives off heat energy. Greenhouse gases like carbon dioxide, methane, and water vapour then trap some of this heat in our atmosphere, similar to a blanket keeping us warm.

Human activities, especially burning fossil fuels, have increased these greenhouse gases in our atmosphere. This means more heat is being trapped, affecting Earth's temperature balance.

Have a go at some of the reflection questions below appropriate to your level.

Beginner

1. What happens to sunlight when it reaches Earth? Think about where it goes and what it does to our planet.
2. Why do we say greenhouse gases work like a blanket around Earth?
3. Draw arrows to show how sunlight travels from the Sun to Earth and what happens next.

Intermediate

1. How do greenhouse gases work with heat energy in our atmosphere? Explain the process using the blanket comparison.
2. What are the different forms of energy involved in the greenhouse effect? List them in order.
3. If Earth had no greenhouse gases, what would happen to the heat from the Sun? Explain your reasoning.

Expert

1. Compare and contrast how energy moves through the greenhouse effect at two stages: 1) when sunlight first reaches Earth and 2) when Earth's surface releases heat.
2. Explain why some types of radiation can pass through greenhouse gases while others are trapped. Use your knowledge of energy and wavelengths.
3. Analyse the energy transfer processes in the greenhouse effect. What happens to the energy at each stage and how does this maintain Earth's temperature?