Carbon Cycle Flashcards
Carbon Sink
Absorbs > releases
Carbon Source
Releases > absorbs
Lithosphere as a carbon store
99.9% Sedimentary rock 0.004% fossil fuels Leaf litter Humic substances
Hydrosphere as a carbon store
0.04%
Dissolved in rivers, lakes, oceans
96% in twilight zone
Cryosphere as a carbon store
0.001%
Permafrost
Atmosphere as a carbon store
0.001%
CO2 and methane
Biosphere as a carbon store
0.004% Vegetation Plant litter Soil hummus Peat Animals
7 Carbon Flows
Respiration Photosynthesis Decomposition Weathering Combustion Ocean Uptake / Loss Sequestration
Local scale example
Tree
Sere example
Deciduous woodland
Continental example
Geological
3 Natural Changes in Carbon Cycle overtime
Wildfires
Volcanoes
Orbital Changes
4 Human Changes in Carbon Cycle overtime
Deforestation
Farming
Urbanisation
Fossil fuel combustion
Urbanisation key facts
2% of land
47% of carbon emissions
97% of anthropogenic emissions
Cement: 2-5% of anthropogenic emissions
Percentage of US methane emissions due to cattle rumination
20%
Carbon Budget
Difference between inputs and outputs of carbon
Links to carbon sources and sinks
Carbon impacts on the Atmosphere
Warming
More intense storms
Increased ghg’s and change in albedos reduces radiative forcing, further temp increase
Regional climate: deforestation= drier and less humid
Carbon impacts on the Land
Increased photosynthesis, longer growing seasons
Increased rate of decay, increases cycling of biospheric carbon + more respiration
Increased wildfire frequency
Decreased cryospheric stores as permafrost melts- increases decomposition
Carbon impacts on the Oceans
Increased acidity- marine life- food source
Melts sea ice, reduces amount of radiation reflected, increases temperature
Ocean salinity decreases, more freshwater from ice melt, slows down large scale ocean currents, climate impacts
Warm water holds less dissolved CO2
Main Carbon Flows in a Tree
Photosynthesis
Sequestration (biological sequestrator)
Decomposition
Respiration
Main Carbon Transfers in a Deciduous Woodland
Rock exposed- weathering
Vegetation colonises- photosynthesis + respiration
Leaf litter- decomposition
Animals- circulate carbon
Eventually environmental equilibrium- climatic climax
Main Carbon Transfers at a Geological Scale
Weathering- slowly dissolves compounds
Dead organisms compacted on seabed- sedimentary rock
Volcanoes- eruptions
