<Li> The sediments, including fossil fuels, fresh water systems and non-living organic material . </Li> <Li> The Earth's interior, carbon from the Earth's mantle and crust . These carbon stores interact with the other components through geological processes </Li> <P> The carbon exchanges between reservoirs occur as the result of various chemical, physical, geological, and biological processes . The ocean contains the largest active pool of carbon near the surface of the Earth . The natural flows of carbon between the atmosphere, ocean, terrestrial ecosystems, and sediments is fairly balanced, so that carbon levels would be roughly stable without human influence . </P> <P> Carbon in the Earth's atmosphere exists in two main forms: carbon dioxide and methane . Both of these gases absorb and retain heat in the atmosphere and are partially responsible for the greenhouse effect . Methane produces a larger greenhouse effect per volume as compared to carbon dioxide, but it exists in much lower concentrations and is more short - lived than carbon dioxide, making carbon dioxide the more important greenhouse gas of the two . </P>

Where is most of the earths carbon stored