How does diffusion process work in carbon cycle?

In the carbon cycle, diffusion refers to the exchange of carbon between the atmosphere and the ocean. Depending on the concentration of carbon, carbon dioxide will either flow from the ocean to the air or from the air to the ocean. From this process of diffusion, carbon is able to enter other phases of the carbon cycle, such as plant respiration and the burning of fossil fuels.

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Carbon makes up all life on Earth. The carbon cycle describes the movement of carbon between different areas. Diffusion is the process through which carbon moves between the surface of the ocean and the atmosphere.

The direction of diffusion in the carbon cycle follows the rules for gas molecules in which they move from regions of high concentration to regions of low concentration. Diffusion is dependent on what is called the concentration gradient. If the concentration of carbon dioxide is higher in the air than in the ocean, then carbon flows into the ocean. If the concentration of carbon dioxide is higher in the ocean than in the air, then carbon dioxide flows from the ocean into the air. Typically, carbon flows from the ocean to the air above tropical waters and from the air to the ocean in cooler, high-latitude waters.

If diffusion goes from the air into the oceans, carbon then becomes embedded into the sediment in the deep ocean. Eventually, this sediment will play a role in the formation of sedimentary rock. From there, it is accessed by humans through the extraction of oil and coal and is deposited into the environment through the burning of fossil fuels. Now with carbon in the air again, it will return to the ocean through another cycle of diffusion.

If diffusion goes into the air from the oceans, plants take in carbon dioxide through the process of photosynthesis. Animals then consume plants, and carbon is transferred to them. When plants and animals die and decay, carbon is transferred into the ground. The carbon in the ground will eventually erode into the ocean or be accessed by humans and burned as fossil fuels, playing a role in another cycle of diffusion.

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