Carbon Flashcards
What is the largest carbon store and how much?
The geological store, 100,000,000 PgC - includes sedimentary rocks etc
What is the biggest terrestrial carbon store and how much?
Soil, 1,950 PgC. It stores more than the surface of the ocean.
What is a carbon flux?
The exchange of stores over a time period
How many tons of carbon is released per year by volcanic outgassing?
300 million tons
What are the 4 key processes of the biogeochemical carbon cycle?
Photosynthesis, respiration, decomposition, combustion.
What is the largest carbon flux?
Photosynthesis, 123 PgC/y
Thermohaline circulation
The global system of surface and deep water currents is driven by temperature and salinity differences. Cold water stores more CO2. More salty water is denser and sinks. MELTING ARCTIC SEA ICE MAY DISRUPT THIS
Biological pump
Phytoplankton make up half the planets biomass and sequester 2 billions tons of CO2 anually to the deep ocean.
Carbonate pump
Calcium carbonate shells of crustaceans and many other shellfish dissolve and become a part of deep ocean currents, or build up on the sea floor and form limestone sediments.
Physical pump
CO2 concentration is 10% higher in the deep ocean than at the surface, More than twice as much CO2 can dissolve into cold polar waters than warm equatorial waters.
Cold water sinks and takes CO2 down.
What is soil health + productivity influenced by?
Stored carbon, and less can lead to soil erosion and water insecurity.
3 features of a healthy soil
- dark and crumbly
- enable infiltration and percolation
- contain many worms and other organisms
How is carbon passed into soils?
Through the decay of leaf litter and other dead material.
Why is fossil fuel combustion the main cause of global warming?
Because it moves stored carbon from the long term geological to the atmosphere without any corresponding increases in sinks.
Define energy security
Having access to enough reliable, affordable energy to meet demand. The energy mix should be more reliant on domestic than imported energy.
3 trends in energy consumption in the UK
-Coal use has declined due to higher carbon taxes
-oil has remained the same since 1965 as it provides 97% of fuel for transport
-gas consumption has increased as it is a cleaner energy source.
Developing energy mix
biomass and waste, natural resources, limited fossil fuel use except oil for transport and coal for power stations.
emerging energy mix
more oil use as more people get cars, tehnology develops and nuclear can be used, some may increase use of renewables.
Developed energy mix
oil use remains high, more gas is used, pollution concerns lead to more clean energy sources.
5 factors that affect energy mix
physical availability, cost, technology, political considerations and environmental priorities.