Where is the majority of the Earth's carbon stored?

The majority of the Earth's carbon is actually stored in the oceans, which contain the largest reservoir of carbon in the form of dissolved carbon dioxide, organic matter, and carbonate minerals. Tackling the carbon cycle involves understanding that while trees (and forests) do store significant amounts of carbon, particularly in biomass, they represent a smaller portion compared to what is stored in the oceans.

When considering the significant carbon reservoirs, the oceans hold about 38,000 gigatonnes of carbon, whereas trees and forests, collectively, store around 650 gigatonnes. In addition to the physical storage within water, the oceans also play a crucial role in the cycling of carbon through processes like photosynthesis by marine phytoplankton and the carbon exchange between the atmosphere and ocean surface.

Soil also contains a considerable amount of carbon, largely in the form of organic matter, but it is still not as substantial as the carbon stored in oceanic environments. The atmosphere holds a smaller amount of carbon primarily as carbon dioxide but is significant in terms of its role in influencing climate and weather patterns.

Understanding these carbon reservoirs helps clarify the complex interactions within the carbon cycle essential for life on Earth and the implications of carbon cycling on climate change.