Cycle and
Energy
Security
Enquiry Question 1: How does the carbon cycle operate to
maintain planetary health?
, 6.1 Most global carbon is locked in terrestrial stores as part of the long-term geological
cycle
The carbon cycle is the exchange of carbon between its four main reservoirs - the
atmosphere, terrestrial biosphere, oceans and sediments.
Carbon Stores
Terrestrial Oceans Atmosphere
Rocks, eg: CaCO3 in
limestone Dissolved CO2
Fossil fuels, eg: coal, oil, Plants/animals, eg:
gas phytoplankton, eaten by
CO2 and CH4 gas
Plants/animals zooplankton, eaten by
Soils, eg: organic carbon fish
from dead plants Ocean sediment
Permafrost, CH4
Carbon Pools/Stores
Store Size of the Store Form
100,000,000 PgC Sedimentary rocks
4,000 PgC Fossil fuels
Terrestrial
1,500 PgC Soils
560 PgC Plants
38,000 PgC Ocean
Oceans
1,000 PgC Ocean surface
Atmosphere 750 PgC CO2 and CH4
Carbon Storage (1860)