1. THE CARBON CYCLE

2. What Is Carbon? Carbon (C) is an element
All things (matter) are made of elements
Carbon is the most important element found in ALL LIFE

3. Carbon Cycle
Because carbon sticks easily to other elements, it is constantly moving
The same carbon atoms are used repeatedly on earth.
They cycle between the different spheres of Earth

4. What are the spheres of Earth?
Earth is divided up into four main spheres:

5. The Atmosphere
The atmosphere is the layer of gases surrounding the Earth

6. The Hydrosphere
The hydrosphere is anywhere that water exists on Earth (the Water Cycle)

7. The Geosphere
The Geosphere (also known as Lithosphere) is all the solid parts of the Earth

8. The Biosphere
The Biosphere is anywhere on Earth that life exists

9. Processes that Transfer Carbon
Between Earth’s Systems (Spheres)
- Photosynthesis
- Consumption
- Respiration
- Decomposition
- Combustion
- Weathering
- Degassing
- Dissolution

10. Photosynthesis
Plants use energy, water and carbon dioxide to produce their own food in a process called photosynthesis

11. Consumption
When primary consumers eat plants, they eat the carbon as well.
If a secondary consumer eats a primary consumer, the carbon is also transferred

12. Respiration Animals breathe out carbon through respiration
Plants release a bit of carbon as well

13. Decomposition
When plants and animals die, most of their bodies are broken down and the carbon in their bodies is returned to the atmosphere.
Some carbon is not decomposed fully and end up in the geosphere underground (soil, oil, coal, etc.) or at the bottom of ocean.

14. Combustion (Burning)
Forest and grass fires are a natural, required part of the carbon cycle that release carbon into the atmosphere and geosphere.
Fire returns carbon to the soil and “cleans out” unhealthy plants, allowing new plants to grow.

15. Weathering
Carbon in rocks and underground is released very slowly into the atmosphere.
This process takes many years

16. Degassing
When carbon dioxide in the ocean comes under pressure, it is sometimes released into the atmosphere

17. Dissolution
Carbon dioxide in the atmosphere sometimes dissolves into the ocean (especially if the water is cold)

18. Carbon Cycle Diagram

19. Activity #1
You will now act as Carbon atoms in the Carbon Cycle (before the arrival of humans)
Like Carbon, you will move between different spheres
Keep track of the places you visit and record the process that got you there.

20. The Industrial Revolution
A time when humans started making things in factories
Factories needed power
To get this power humans would burn coal, which released a lot of Carbon Dioxide into the atmosphere

21. Activity #2
You will now act as Carbon atoms in the Carbon Cycle (since the arrival of humans)
Like Carbon, you will move between different spheres
Keep track of the places you visit and record the process that got you there.

22. Conclusion Questions
1. Compare your journey in Activity #1 (before humans) with your journey in Activity #2 (since humans). What were the similarities and differences?
2. What effect does too much carbon in the atmosphere and ocean?
3. If too much Carbon Dioxide in the atmosphere is a problem, what are some ways we could reduce it?