The idea
Carbon atoms move between the atmosphere, living things, the oceans, soil, and rock. Not one atom is created or destroyed — the same carbon has been through countless organisms before you.
graph TD ATM["Atmosphere: CO2"] -->|photosynthesis| PLANTS["Producers"] PLANTS -->|eaten| ANIMALS["Consumers"] PLANTS -->|respiration| ATM ANIMALS -->|respiration| ATM ANIMALS -->|death| SOIL["Soil and decomposers"] PLANTS -->|death| SOIL SOIL -->|decomposition| ATM SOIL -->|"buried over millions of years"| FOSSIL["Fossil fuels"] FOSSIL -->|combustion| ATM ATM <-->|dissolving| OCEAN["Oceans"]
The slow loop and the fast loop
Two paths matter here, and they run at wildly different speeds:
- The fast loop — photosynthesis, respiration, decomposition. Days to decades. Balanced for most of human history.
- The slow loop — burial into fossil fuels and weathering back out. Millions of years.
Burning fossil fuels takes carbon out of the slow loop and injects it into the fast one. That is climate change in a sentence.
Something to sit with
The carbon dioxide released by a car this afternoon may spend the next century in the atmosphere. Which of the arrows above decides how long it stays?
Curriculum connection
B2.2
explain how naturally occurring phenomena, including the cycling of matter and the flow of energy, contribute to the dynamic equilibrium within and between ecosystems
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B2.6
identify and use various indicators of climate change to describe the impacts of climate change on local and global ecosystems, and analyse how human activities contribute to climate change
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