The Carbon Cycle Flashcards
What is Carbon
A really important element
What is an organic store?
Living things
What is an inorganic store?
Rocks, Gases and fossil Fuels
Where is carbon found?
Organic and Inorganic store
Where is 99.9% of the Earths carbon stored?
In sedimentary rocks like limestone
How much of the Earths carbon is stored in fossil fuels in the lithosphere?
0.004%
How is carbon stored in the atmosphere?
Carbon dioxide and in similar quantities to methane
How much of the earths carbon does the atmosphere contain?
0.001%
How is carbon stored in the Biosphere and when is it transferred?
In the tissue of living. organisms and is transferred to soil when living organisms die and decay
How much of the earths total carbon does the biosphere contain?
0.004%
How much of the earths carbon does the cryosphere contain?
0.1%
What is permafrost?
Permanently frozen ground
How is carbon stored in the cryosphere?
It’s in soil in areas of permafrost where decomposing plants and animals have frozen into the ground
What is the carbon cycle?
The process that carbon is stored and transferred
What type of system is it?
Closed - There’s inputs and outputs of energy. but the amount of carbon is the same
How is carbon stored long term?
In rocks and fossil fuels deep underground
What are the 7 flows of carbon between stores?
- Photosynthesis
- Respiration
- Decomposition
- Weathering
- Sequestration
- Ocean uptake and loss
- Combustion
What does photosynthesis do?
Transfers carbon stored in the atmosphere to biomass
How does photosynthesis happen?
Plants and phytoplankton use energy from the sun to change CO2 and H2O into glucose and oxygen enabling plants to grow
How is carbon passed and released?
Passed through the food chain and released through respiration and decomposition
What does respiration do?
Transfers carbon from living. organisms to the atmosphere
How does respiration work?
Plants and animals break down gluecose for energy, releasing CO2 and methane in process
What does do decomposition?
Transfers carbon from dead biomass to the atmosphere and the soil
What happens after the death of organisms?
Bacteria and fungi break them down. CO2 and methane. are released. some carbon is transferred to the soil in. the form of humans
What does chemical weathering do?
Transfers carbon from the atmosphere to the hydrosphere and biosphere
How is acid rain form?
Atmospheric carbon reacts with water vapour to form acid rain, when this falls onto rocks a chemical reaction occurs. The molecules resulting from this reaction may be washed into the sea. Here they react with CO2 dissolved in water to form calcium carbonate, used by sea creatures
What is sequestration?
Carbon from the atmosphere can be captured and held in sedimentary rocks or fossil fuels. Rocks and fossil fuels over millions of years when dead animal and plant material in the ocean falls to. the floor and compacted
What happens to carbon in fossil fuels
Carbon is sequestered until we burn them
Explain ocean uptake and loss
CO2 is dissolved from the atmosphere into the ocean. It’s transferred to the oceans when its taken up by organisms that live in them
When is carbon transferred from the ocean to the atmosphere
When carbon-rich water from deep in the oceans rises to the surface and releases CO2
What does combustion do?
Transfers carbon stored in living, dead or decomposed biomass to the atmosphere by burning
What causes carbon flow
Wildfires
What are fast carbon flows
Photosynthesis, respiration, combustion and decomposition
What is a slow carbon flow
Sequestration - it takes millions of years for carbon to be sequestered in sedimentary rocks
What else does the carbon flow depend on?
Spatial scale
What are the main flows at a plant scale
Respiration and Photosynthesis
What are the main flows at a ecosystem scale
Carbon flows - Combustion and decomposition occur
What are the main flows at a Continental scale
All of the carbon flows (including sequestration)
What 2 natural events alter. the magnitude of a carbon store?
Wildfires and Volcanic Activity
What do wildfires do?
Rapidly transfer large quantities of carbon from biomass to the atmosphere
What happens if there’s a loss of vegetation?
Decreases photosynthesis so less carbon is removed from the atmosphere
WHat happens to wildfires in the long term?
Fires encourage the growth of new plants, which take in carbon from the atmosphere for photosynthesis.
Where is carbon stored?
Within the earth in magma and is released during volcanic eruptions. The majority enters the atmosphere as CO2
What has happened since the industrial revolution?
The impact. that humans have on the carbon cycle has increased hugely. Currently we’re causing. carbon flows from the lithosphere and biosphere to the atmosphere to happen much faster than they naturally would
What are the 4 main human causes of change?
- Hydrocarbon (fossil fuel) extraction and use
- Deforestation
- Farming practices
- Land use change
What is hydrocarbon extraction?
Extracting and burning (combustion) of fossil fuels releases CO2 into the atmosphere
What would happen without human intervention?
The carbon would remain sequestered in the lithosphere for thousands or millions of years to come
Why are forests cleared?
For agriculture, logging or to make way for new developments
what does forest clearance cause?
Reduces the size of carbon stores and if the cleaned forest id burned. there’s a rapid flow of carbon from the biosphere to the atmosphere
What 3 ways does agricultural activities release carbon to the atmosphere?
- Animals release CO2 and methane when they respire and digest food
- Ploughing releases CO2 stored in the soil
- Growing rice in rice paddles releases a lot of methane
What has happened as a result of the of the population rising?
Food production has risen - carbon emissions from farming practices has increased. Mechanisation of farming has increased CO2 emissions
What 2 ways does land use change cause change
- Vegetation is removed to make way for buildings - reducing carbon storage in the biosphere
- Concrete production releases lots of CO2 and lots of concrete is used when urban areas expand
What is carbon budget
The difference between the inputs of carbon into a subsystem and outputs of carbon from it
Where do inputs of carbon come from in the atmosphere?
Volcanic eruptions, burning fossil fuels, respiration and ocean loss
Where do outputs of carbon come from in the atmosphere?
Photosynthesis, sequestration, decomposition, chemical weathering and ocean uptake.
What does the balance of inputs and outputs of a subsystem determine?
Whether it acts as a carbon source the outputs of carbon outweigh the inputs, so it releases more carbon than it absorbs) or a carbon sink (the inputs of carbon outweigh the outputs, so it absorbs more carbon than it releases)
When there is a change to the carbon cycle what does it affect?
Atmosphere and climate, land and oceans
what does the carbon cycle affect in the atmosphere?
The amount of gasses containing carbon
What type of gases are in the atmosphere?
Greenhouse gases - They trap some of the suns energy keeping some of the heat in and keeping the plant warm
Why doest the concentration of greenhouse gases rise?
The changes in the carbon system caused by human activity like deforestation and the burning of foosil fuels
What happens as the concentration of greenhouse gases rise and what is this called
The temperatures rise - Global Warming
What would happen if there was no carbon in the atmosphere
Plant’s wouldn’t photosynthesise. If there was no decomposition, dead plants would remain where they fell. and their nutrients would never be recycled
WHat does changes in the carbon cycle do to the amount of carbon stored in. the land?
It reduces - warmer temperatures caused by global warming are causing permafrost to melt and releases carbon previously stored in the permafrost to the atmosphere
What does an increase in global temperatures cause?
increase the frequency of wildfires
How is CO2 in oceans used?
Used by organisms like phytoplankton and seaweed during photosynthesis and by other marine organisms to form calcium carbonate shells and skelentons
How does increased CO2 in the atmosphere effect the oceans
Increases the acidity of the oceans because oceans initially absorb more CO2 this has adverse effects on marine life
How does global warming affect oceans?
Organisms that are more sensitive to. temperature photoplankton may not be able to survive higher temperatures so their numbers decrease. Meaning less CO2 is used for photosynthesis, so less carbon is removed from the atmosphere
What happens when warmer water tries to absorb CO2
It absorbs less CO2, so temperatures rise the amount of CO2 that could potentially be dissolved in the sea decreases
