1. THE CARBON CYCLE

2. What Is Carbon? Carbon is one of the most abundant elements on Earth, and is known as “the basic building block of life”. The basis of life on earth – a continual supply of carbon is essential for all living organisms. The total amount of carbon on Earth, whether we are able to measure it accurately or not, always remains the same (although the carbon regularly changes its form). Found in rocks, oceans, atmosphere, plants, living organisms, etc…

3. Carbon Cycle The same carbon atoms are used repeatedly on earth (because new matter can never be created – it is essential that living things be able to reuse the existing matter again and again). The carbon atoms cycle between the earth and the atmosphere.

4. Plants Use Carbon Dioxide Plants pull carbon dioxide from the atmosphere and use it to make food –— photosynthesis. The carbon becomes part of the plant (stored food).

5. Animals Eat Plants When organisms eat plants, they take in the carbon and some of it becomes part of their own bodies.

6. Plants and Animal Die When plants and animals die, most of their bodies are decomposed and carbon atoms are returned to the atmosphere. Some are not decomposed fully and end up in deposits underground (oil, coal, etc.).

7. Carbon Slowly Returns to Atmosphere Carbon in rocks and underground deposits is released very slowly into the atmosphere. This process takes many years.

8. Cycle – Repeats Over and Over and Over and Over …

9. Carbon Cycle Diagram Carbon in Atmosphere Plants use carbon to make food Animals eat plants and take in carbon Plants and animals die Decomposers break down dead things, releasing carbon to atmosphere and soil Bodies not decomposed — after many years, become part of oil or coal deposits Fossil fuels are burned; carbon is returned to atmosphere Carbon slowly released from these substances returns to atmosphere

10. Carbon in Oceans Additional carbon is stored in the ocean. Many animals pull carbon from water to use in shells, etc. Animals die and carbon substances are deposited at the bottom of the ocean. Oceans contain earth’s largest store of carbon.

11. The Carbon Cycle

12. Human Impact Fossil fuels release carbon stores very slowly Burning anything releases more carbon into atmosphere — especially fossil fuels Increased carbon dioxide in atmosphere increases global warming Fewer plants mean less CO 2 removed from atmosphere

13. What We Need to Do Burn less, especially fossil fuels Promote plant life, especially trees