Carbon Cycle

• carbon is an...?


  element

  • a very important one
• where is carbon found


  in organic stores (living things) and inorganic stores
• examples of inorganic stores


  rocks

  gases

  fossil fuels
• 5 earth systems are ...


  lithosphere

  hydrosphere

  biosphere

  atmosphere

  cryosphere
• Where is carbon found in the lithosphere?


  • over 99.9% carbon on Earth stored in sedimentary rocks
  • 0.004% carbon on Earth stored in fossil fuels , in the lithosphere
• example of sedimentary rock


  limestone
• example of fossil fuel


  coal

  oil
• what % of the carbon on Earth is stored in sedimentary rocks?


  over 99.9%
• what % of carbon in earth is stored in fossil fuels?


  0.004%
• where is carbon found in the atmosphere


  • carbon stored as CO2 and in smaller quantitaties as CH4 in the atmosphere
• What % of carbon does the atmosphere contain?


  about 0.001% of the Earth's carbon
• hydrosphere- what is CO2 dissolved in ?

  rivers, lakes, oceans
• hydrosphere - oceans


  The oceans are the 2nd largest stores of carbon on earth

  • majority of carbon here found deep in ocean - found in form of dissolved inorganic carbon
  • a small amount found at the ocean surface where it is exchanged with the atmosphere
• what % of the earth's carbon do the oceans contain?


  0.04%
• Where is carbon found- BIOsphere


  • stored in tissues of living organisms- transferred to soil when they die and decay
• What % of the earths carbon does the biosphere contain


  0.004%
• how much earths carbon does the cryosphere contain?


  less than 0.01%
• where is carbon found- cryosphere?


  Most of the carbon in the cryosphere is in the soil in areas of permafrost where decomposing plants & animals have frozen into the ground
• What is permafrost


  permanently frozen ground
• define carbon cycle 


  the process by which carbon is stored and transferred
• is carbon cycle an open or closed system


  closed
• The carbon cycle is a ....


  CLOSED system- there are inputs and outputs of energy, but the amount of carbon in the system remains the SAME

  • some carbon is locked away in long-term stores - if these are released - they are effectively inputs
• another word for carbon being locked away?


  sequestered
• What LONG TERM stores is carbon locked away in

  rocks and fossil fuels deep underground

  • if these are released (eg burning fossil fuels) they are effectively inputs
• Flows of carbon =
• flows of carbon ....


  Photosynthesis

  Combustion

  Ocean uptake & loss

  Sequestration

  Respiration

  Decomposition

  Weathering
• Flows of carbon- photosynthesis


  • transfers carbon stored in the atmosphere to biomass
• Flows of carbon- photosynthesis ?


  Plants & phytoplankton use energy from the SUN to change CO2 and water --> glucose and oxygen

  • this enables plants to GROW
• flows of carbon- photosynthesis


  Carbon is passed through the FOOD CHAIN and released through RESPIRATION AND DECOMPOSITION
• Flows of carbon- combustion


  transfers carbon stored in living, dead or decomposed biomass (including peaty soils) to the atmosphere by BURNING

  • WILDFIRES can cause carbon flow
• Flows of carbon- OCEAN UPTAKE AND LOSS


  • CO2 is directly dissolved from the atmosphere into the ocean - it is also transferred to the oceans when it is taken up by organisms that live in them
• Flows of carbon- ocean uptake and loss

  carbon is transferred from the ocean to the atmosphere when carbon-rich water from deep in the oceans rises to the surface and releases CO2
• Flows of carbon- Sequestration?


  • carbon from the atmosphere can be sequestered in sedimentary rocks or as fossil fuels
  • Rocks and fossil fuels form over millions of years when dead animal and plant material in the ocean falls to the floor & is compacted
• flows of carbon-sequestration


  carbon in fossil fuels is sequestered until we burn them (combustion)
• flows of carbon- respiration- what does respiration do


  respiration transfers carbon from living organisms to the atmosphere
• flows of carbon-respiration


  Plants & animals break down glucose for energy, releasing CO2 and methane in the process
• methane is a what


  gas

  • contains carbon
• flows of carbon- what does decomposition do?


  transfers carbon from dead biomass to the atmosphere and the soil
• flows of carbon- decomposition


  After death, bacteria and fungi break organisms down. CO2 and methane are released

  Some carbon transferred to the soil in the form of HUMUS
• Flows of carbon- weathering?


  chemical weathering transfers carbon from the atmosphere to the hydrosphere and biosphere