The Global Carbon Cycle

Carbon is the fundamental building block of life on Earth. The global carbon cycle describes the movement of carbon between four major stores — the lithosphere, atmosphere, hydrosphere, and biosphere — through a series of biological, chemical, and physical processes. Like the water cycle, the global carbon cycle is effectively a closed system at the planetary scale: the total amount of carbon on Earth is fixed, but it is continuously redistributed between stores. Understanding the carbon cycle is essential for explaining climate change, one of the most important issues in contemporary geography.

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Carbon Stores

The four major stores vary enormously in size: