Water and carbon cycle 5 - The carbon cycle Flashcards
Where is carbon found
In organic and inorganic stores
What’s an organic store
Living things
What’s an inorganic store
Rocks gases and fossil fuels.
What 5 systems is carbon found in
- Lithosphere
- Atmosphere
- Biosphere
- Cryosphere
- Hydrosphere
How much of the earths carbon is stored in sedimentary rocks
99.9%
How much of the earths carbon is stored in fossil fuels
0.004%
How is carbon stored in the atmosphere
As carbon dioxide and in small quantities as methane
How much of the earths carbon is stored in the atmosphere
0.001%
How does carbon enter the hydrosphere
Through dissolving into ocean water
How do the organisms use carbon
To produce shells
How much of the earths carbon is stored in the hydrosphere
0.0076%
How is carbon stored in the biosphere
In the tissue of living organisms
How is it transferred to the soil
When living organisms die and decay
How much of the earths carbon is stored in the biosphere
0.004%
How much of the earths carbon is stored in the cryosphere
0.1%
What is carbon like in the cryosphere
Most in soil in areas of permafrost where decomposing plants and animals have frozen into the ground
What happens in the carbon cycle process
Carbon is stored and transferred
What kind of system is it
A closed system - there’s inputs and outputs of energy, but the amount of carbon remains the same
What happens to some of the carbon
It is locked away in long term stores like rocks and fossil fuels deep underground
What are the 7 flows of carbon between stores
1) photosynthesis
2) Respiration
3) Decomposition
4) Weathering
5)Sequestration
6) Ocean uptake and loss
7) Combustion
What stores does photosynthesis transfer between
From the atmosphere to biomass
How does photosynthesis work
Plants and phytoplankton use energy from the sun to change CO2 and water into glucose and oxygen enabling plants to grow
How is carbon moved
Passed through the food chain and released through respiration and decomposition
What stores does respiration transfer between
Living organisms to the atmosphere
How does respiration work
Plants and animals break down glucose for energy, releasing CO2 and methane in the process
What does decomposition do
Transfers carbon from dead biomass to the atmosphere and the soil
What happens after the organism is dead
Bacteria and fungi break down organisms and CO2 and methane are released
Where does some of the carbon of the decomposition go
It’s transferred to the soil in the form of humus
Where does chemical weathering transfer carbon?
From the atmosphere to the hydrosphere and biosphere
How does chemical weathering work
Atmospheric carbon reacts with water vapour to form acid rain. This acid rain falls onto rocks and causes a chemical reaction which dissolves the rocks. The molecules resulting from this reaction maybe washed to the sea. Here they react with CO2 dissolved in the water to form calcium carbonate which is used by sea creatures
What does sequested mean
Captured and held
How is carbon sequestered
Carbon from the atmosphere is sequestered in rocks or fossil fuels
How long is carbon sequestered in fossil fuels for
Until we burn them
How is carbon transferred in ocean uptake and loss
It’s directly dissolved from the atmosphere into the ocean
When else is it transferred to the ocean
When it’s taken up by organisms that live in them
When else is it transferred from the ocean to atmosphere
When carbon-rich water from deep in the oceans rises to the surfaces 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
How long do fast carbon flows take
They’re fast - a matter of minutes, hours or days
What are 4 examples of fast carbon flows
1) Photosynthesis
2) Respiration
3) Combustion
4) Decomposition
What’s an example of a slow carbon flow
Sequestration
How long does sequestration take
Millions of years
What else does the carbon flow depend on
The spatial scale
What is it like on an ecosystem scale
Carbon flows like combustion and decomposition also occur
What is it like on a plant scale
Respiration and photosynthesis are the main flows
What’s it like on a continental scale
All carbon flows such as sequestration occur
What alters the magnitude of the carbon stores
Natural events like wildfires and volcanic eruptions
What do wildfires do?
Rapidly transfer large quantities of carbon from biomass to the atmosphere
What does loss of vegetation do
Decreases photosynthesis so less carbon is removed from the atmosphere in the long term
What can fire encourage
The growth of new plants, which take carbon in from the atmosphere for photosynthesis
When can fires have a neutral effect on atmospheric carbon
The amount and type of regrowth
What happens during volcanic eruptions
Carbon stored in the earths magma is released during eruptions, the majority enters the atmosphere as cO2
What would happen if there is a large volcanic eruption
Would destroy the carbon cycle significantly
What has happened since the Industrial Revolution
The impact humans have on then carbon cycle has increased hugely
What are we causing
Carbon flows from the lithosphere and biosphere to the atmosphere to happen much quicker than they normally would
What are the 4 main causes of change
1) Hydrocarbon extraction and use
2) Deforestation
3) Farming practices
4) Land use changes
What does hydrocarbon extraction and use cause
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
Why are forests cleared
For agriculture, logging or to make way for developments
What does clearance do
Reduces the size of the carbon store
What happens if the clear forest is burned
There’s a rapid flow of carbon from the biosphere to the atmosphere
What 3 ways does agricultural activities release carbon into the atmosphere
1) Animals release CO2 and methane when respire and digest food
2) Ploughing can release CO2 stored in soil
3) Growing rice in rice paddies releases a lot of methane
What has happened as the worlds population has increased
food production has increased
What has happened as a result of this
carbon emissions from farming have increased
what else has increased CO2 emissions
Mechanization of farming
Give 2 reasons for this
1) Vegetation is removed to make way for new buildings - reducing carbon storage in the biosphere
2) Concrete production releases lots of CO2 and lots of concrete is used when urban areas expand
What else is a major source of carbon
The change of land use from natural or agricultural to urban
What is carbon budget
The difference between inputs of carbon into a sub system and outputs of carbon
Give an example of this
In the atmosphere inputs of carbon come from volcanic eruptions, burning fossil fuels, respiration and ocean loss and outputs through photosynthesis, sequestration, decomposition, chemical weathering and ocean uptake
What does the balance of the sub system determine
Whether it acts as a carbon sink or a carbon source
Whats a carbon source
The outputs of carbon outweigh the inputs so it releases more carbon than it absorbs
Whats a carbon sink
The inputs of carbon outweigh the outputs, so it absorbs more carbon than it releases
What happens when there is a change to the carbon cycle
Has significant impacts on the atmosphere, land and oceans
How does the carbon cycle affect the atmosphere
Affects the amount of gases containing carbon in the atmosphere
What are these gases called
Greenhouse gases
Why are they greenhouse gases
They trap some of the sun’s energy, keeping some of the heat and keeping the plant warm
Why are concentrations of greenhouse gases increasing
Due to the burning of fossil fuels
What is happening because of this
Temperatures are expected to rise
What is this called
Global warming
What does changes in temperatures across the globe cause
Affect other aspects of the climate eg - more intense storms are predicted
What dies the carbon cycle allow for
Allows plants to grow
What would happen if there was no carbon in the atmosphere
Planets wouldn’t photosynthesise
What would happen if there was no decomposition
Dead plants would remain where they fell and their nutrients would never be recycled
What happens to the changes in carbon cycle
Reduce the amount of carbon stored in the land
What do warmer temperatures cause
Permafrost to melt
What happens as there is an increase in global temperatures
Increase in the frequency of wildfires
What happens to the CO2 as part of the carbon cycle
CO2 is dissolved directly into the oceans from the atmosphere
How is CO2 in oceans used
Used by organisms like phytoplankton and seaweed during photosynthesis by other marine organisms to form calcium carbonate shells and skeletons
What does the increase levels of CO2 in the atmosphere cause
Increase the acidity of the oceans as they initially absorb more CO2.
How does this affect marine life
Can have adverse effects
What else affects oceans
Global warming
Why do some numbers of plants decrease
Some organisms are sensitive to temperature such as phytoplankton may not be able to survive high temperatures
What does this mean
Less CO2 is used by them for photosynthesis, so less carbon is removed from the atmosphere
What happens as temperatures rise
The amount of CO2 that could potentially be dissolved in the sea decreases
Why is this
Because warmer water is less able to absorb CO2
