Overview:
- Terrestrial means land and include vegetation (biosphere)
- Biogeochemical carbon cycle is basically all living things, and chemicals
- The carbon cycle is extremely important for ‘planetary health’. It provides carbon as a building-block for life, and carbon dioxide regulates the temperature of our climate by trapping solar energy. Without carbon dioxide, the world would freeze.
Basics:
- Store = the amount of carbon in a store measured in Petagrams
- Main stores are terrestrial, oceanic, atmospheric
- The flux rate is a measure of how much carbon leaves or enters a store in a year (GtC/year)
- Turnover time = total store (GtC) / flux rate (GtC per year)
- In a well-mixed system e.g. the atmosphere, residence time of CO2 molecules are the same as the turnover time
Carbon Store:
|
Size Of Store:
|
Flux Rate:
|
Turnover:
|
Terrestrial (earth, rocks
and soil)
|
Enormous – most of the
Earth’s stores
|
Low
|
Very slow (millions of
years)
|
Oceans
|
Big (deep ocean)
|
Medium
|
Medium – deep ocean
slower (thousands of years)
|
Atmosphere
|
Small
|
High
|
Faster turnover
|
Biosphere (vegetation)
|
Quite fast.
|
Sedimentary Rocks:
Weathering,
erosion and deposition > sediment > compaction &
cementation
Fossil Fuel Formation:
- Ancient forests lived
- And died
- And were buried and compressed by tectonic forces
- To form coal, oil and gas
- Over millions of years increasing heat and pressure forms fossil fuels in the ground storing in coal or shale.
The Role Of Geology:
- Geological processes like volcanoes release carbon dioxide and weathering and erosion of sedimentary rocks like chalk release sediments with carbon in. e.g erosion and weathering in Flamborough Head releases carbon.