The carbon cycle
The 'carbon cycle' refers to the transfer of carbon, in various forms, through the atmosphere, oceans, plants, animals, soils and sediments.
As part of the carbon cycle, plants and algae convert carbon dioxide and water into biomass using energy from the sun (photosynthesis). Living organisms return carbon to the atmosphere when they respire, decompose or burn. Methane is released through the decomposition of plants, animals and other hydrocarbon material (fossil fuels and waste) when no oxygen is present.1
Representation of the carbon cycle
Source: C02CRC, www.co2crc.com.au
1Garnaut, R (2008). 'The Garnaut Climate Change Review: Final Report', Commonwealth of Australia, Cambridge University Press, Port Melbourne. www.garnautreview.org.au