The document discusses the carbon cycle, which involves carbon continually moving through living organisms, oceans, atmosphere, and rocks. There are four main subcycles - the rock subcycle over millions of years, ocean subcycle over hundreds of years, biological subcycle over days to years, and fossil fuel subcycle over millions of years being released in recent decades. Carbon is essential for life and plays a key role in climate as a greenhouse gas.

7. The Carbon Cycle Dissolution Plants Phytoplankton “ Biomass” Fossil Fuels Decomposition Respiration Combustion Carbon In Atmosphere Carbon In Rocks Carbon In Ocean Water Weathering Tectonics Evaporation Lithification Soil Marine Sediment “ Organic Matter” Photosynthesis Boxes are carbon sinks Arrows are carbon fluxes Consumption

10. Carbon Sinks Amount of stored carbon in Billions of Metric Tons (Gt) Note type of Carbon Molecule (State of Matter) CH 2 O (solid or liquid) Terrestrial Plants Phytoplankton “ Biomass” 600 (Gt) Fossil Fuels 10,000 (Gt) Carbon In Atmosphere 750 Gt Carbon In Rocks 100,000,000 (Gt) Carbon In Ocean Water 40,000 (Gt) Consumers, Soil Marine Sediment “ Organic Matter” 1600 Gt H 2 CO 3 (liquid) CO 2 CH 4 (gas) CaCO 3 (solid) CH 2 O (solid) C x H x (solid or liquid)

11. Time Scales Plants Phytoplankton Fossil Fuels Carbon In Atmosphere Carbon In Rocks Carbon In Ocean Water Consumers, Soil Marine Sediment Biological Subcycle Short Term Days - Years Ocean Subcycle Short Term 10’s - 100’s of Years Fossil Fuel Subcycle Long Term Millions of Years Fossil Fuel Subcycle Short Term 10’s of Years Rock Subcycle Long Term Millions of Years

13. Rock Subcycle

15. Rock Subcycle

20. Ocean Subcycle