Carbon Cycle Eq1 Flashcards
What is the carbon cycle
The exchange of carbon between it’s stores: terrestrial, ocean and atmosphere
What is a carbon flux/flow
Process of transferring carbon between stores
What is the largest store of carbon
Earth’s crust
What is the largest flux
Photosynthesis
What are fluxes measured in
Pentagrams per year
What is the shortest flux
Plants absorb carbon from atmosphere through photosynthesis, then release it again through respiration
Takes seconds to minutes
What is the longest carbon flux
Organic matter that is buried in sediments slowly transforms into fossil fuels which we release into the atmosphere when we burn these fossil fuels
Takes millions of years
What does it mean to say that most of the earths carbon is geological
Sedimentary rocks store the largest amount of carbon because of how they are formed
How is sedimentary rock formed
- Dead organic matter from plants and animals falls to bottom of oceans and lakes
- It is covered by silt and mud over time
- Dead organic matter is compressed
- Over millions of years, layers of organic matter and wilt and mud turn into shale
What is the slow carbon cycle with steps
- C02 reacts with water to form carbonic acid
- Silicate weathering occurs = carbonic acid reacts with silicate rock to dorm soluble bicarbonate ions
- Animals use bicarbonate to form shells which turn into carbonate sedimentary rock (through process on other flashcard)
- When the rock subducts as part of the earths crust and is heated to the point of melting, yhe rocks go through metamorphism (where sedimentary rocks turn into metamorphic under intense temperatures and pressures), which releases carbon dioxide
What is carbon sequestration
The capture of carbon from the atmosphere by the ocean, vegetation or sedimentary rocks where it is stored
How is carbon sequestered in the ocean
Through pumps - biological, carbonate, physical
What is the biological pump
Carbon dioxide from atmosphere is absorbed by phytoplankton through photosynthesis, some carbon is released back into teh atmosphere through respiration, the rest is involved in the formation of sedimentary rocks in the deep ocean
What is the carbonate pump
Carbon is transferred from silicate rock to carbon rich sediment through slow carbon cycle
What is the physical pump
Colder water absorbs more carbon than warm water, this cold water is also denser so it sinks, causing there to be a higher concentration of carbon in deep water
This carbon is only released again when it is brought back to teh surface in thermohaline circulation
How can carbon be sequestered into plants and soils
Photosynthesis occurs, the CO2 absorbed in this is transferred through the food chain, digestion occurs and carbon is transferred to the soil through decomposition
How can carbon be stored as dead organic matter
Decomposition transfers carbon from dead biomass to the soil and atmosphere
What impacts how much carbon is stored in soil
Rate of decomposition is slower in dry conditions so there will be less carbon stored
Soils made up of clay store more carbon than sandy soils
Vegetation cover
How does the carbon cycle link to climate change
The carbon cycle affects the amount of gases containing carbon in the atmosphere - these are greenhouse gases
Explain the greenhouse effect
- Solar radiation is transmitted by the sun as short wave radiation
- Short wave radiation is either reflected or passes straight through our atmosphere and hits the earths surface causing warming
- Warmed objects re emit this energy but as long wave radiation
- Greenhouse gases absorb this energy and reflect this long wave radiation
