The Carbon Cycle

Carbon is the basic building block of life, and these unique atoms are found everywhere on Earth. Carbon makes up Earth's plants and animals, and is also stored in the ocean, the atmosphere, and the crust of the planet. A carbon atom could spend millions of years moving through Earth in a complex cycle. This conceptual animation provides an illustration of the various parts of the Carbon cycle. Purple arrows indicate the uptake of Carbon; yellow arrows indicate the release of Carbon.

On land, plants remove carbon from the atmosphere through photosynthesis. Animals eat plants and either breath out the carbon, or it moves up the food chain. When plants and animals die and decay, they transfer carbon back to the soil. Moving offshore, the ocean takes up carbon through physical and biological processes. At the ocean's surface, carbon dioxide from the atmosphere dissolves into the water. Tiny marine plants called phytoplankton use this carbon dioxide for photosynthesis. Phytoplankton are the base of the marine food web. After animals eat the plants, they breathe out the carbon or pass it up the food chain. Sometimes phytoplankton die, decompose, and are recycled in the surface waters. Phytoplankton can also sink to the bottom of the ocean, where they become buried in marine sediment. Over long time scales, this process has made the ocean floor the largest reservoir of carbon on the planet. In a process called upwelling, currents bring cold water containing carbon up to the surface. As the water warms, the carbon is then be released as a gas back into the atmosphere, continuing the carbon cycle.

Carbon is found in the atmosphere as Carbon dioxide, which is a greenhouse gas. Greenhouse gases act like a blanket, and trap heat in the atmosphere. In the past two centuries, humans have increased atmospheric carbon dioxide by more than 30%, by burning fossil-fuels and cutting down forests.


Ivy Flores (IRC/UMBC): Lead Animator
Maria Frostic (UMBC): Producer
Ryan Fitzgibbons (UMBC): Producer
Bruce Cook (NASA/GSFC): Scientist
Gene Feldman (NASA/GSFC): Scientist
Please give credit for this item to:
NASA/Goddard Space Flight Center/UMBC

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Earth Science Week

SVS >> Carbon
SVS >> Carbon Absorption
SVS >> Carbon Cycle
SVS >> Carbon Dioxide
SVS >> Carbon Land Cycle
SVS >> Carbon Monoxide
SVS >> Carbon Ocean Cycle
SVS >> Carbon Release
SVS >> Carbon Sink
SVS >> Earth Science
GCMD >> Earth Science >> Atmosphere >> Atmospheric Chemistry/Carbon and Hydrocarbon Compounds
NASA Science >> Earth

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version