Carbon Cycle Flashcards by Molly Bennett

What is the biogeochemical carbon cycle?

A closed system in which carbon is moved and stored in the lithosphere, biosphere, atmosphere and hydrosphere

How well did you know this?

Not at all

Perfectly

What is the difference between a store and a flux?

A store holds carbon for a long period of time and flux is a transportation of carbon that creates a cycle and feedback

How well did you know this?

Not at all

Perfectly

Why is the carbon cycle important?

Economic development relies on fossil fuels
Energy security and scarcity is the cause of conflict
Combustion of carbon affects the climate
The desire for carbon is destroying ecosystems

How well did you know this?

Not at all

Perfectly

What is different about the willow tree as a store of carbon?

Sequestration and carbon release are equal in concentration so no more carbon dioxide is released that was absorbed

How well did you know this?

Not at all

Perfectly

Name the four carbon stores

Lithosphere
Biosphere
Atmosphere
Hydrosphere

How well did you know this?

Not at all

Perfectly

Describe the lithosphere including the form of carbon stored

The crust and upper mantle - fossil fuel and sedimentary rock deposits

How well did you know this?

Not at all

Perfectly

Describe the biosphere and the store of carbon

Regions of the surface and atmosphere occupied by living organisms - organic molecules in living and dead organisms

How well did you know this?

Not at all

Perfectly

Describe the atmosphere and type of carbon stored

An envelope of gases surrounding the earth - carbon dioxide

How well did you know this?

Not at all

Perfectly

Describe the hydrosphere and carbon stored

All the water stores on the earth surface - dissolved carbon dioxide in the ocean

How well did you know this?

Not at all

Perfectly

Name three rocks carbon is stored in

Limestone, shale and coal

How well did you know this?

Not at all

Perfectly

How significant is the ocean as a store of carbon

It is the largest store of carbon on earth holding approx 80% of the world’s carbon

How well did you know this?

Not at all

Perfectly

How are the Himalayas significant to storing carbon?

A large store of carbon as it started as oceanic sediment so has a lot of calcium carbonate which is actively weathered carbon and transported to the ocean

How well did you know this?

Not at all

Perfectly

Fill in the gaps
80% of carbon containing rock is from shell building aka (1) organisms and plankton which is (2) to form rock such as limestone

1 - calcifying

2 - lithified

How well did you know this?

Not at all

Perfectly

Fill in the gaps

20% of rocks contain (1) carbon formed from (2) in embedded layers of rock which is how (3) is formed

1 - organic
2 - heat and pressure
3 - shale

How well did you know this?

Not at all

Perfectly

How do carbon fossil fuels form?

Takes 300m years
From organic material
Decays anaerobically in rivers and oceans
The deeper the deposit, the more heat and pressure on deposits
When material builds up quicker than it can decay layers of organic carbon form oil, coal and natural gas

How well did you know this?

Not at all

Perfectly

How are oil and gas formed?

Remains of tiny aquatic animals and plants
Gas and oil in pockets of rock migrate through the crust until it meets caprocks
Natural has are fractions of oil molecules found in crude oil
Hydrocarbon deposits include oil shales, tar sands and gas hydrates

How well did you know this?

Not at all

Perfectly

How is coal formed?

Remains of trees, plants and ferns sinking to the bottom of a swamp or damp surrounding
Over time the heat and pressure on deposits produced chemical and physical changes in plant layers which formed peat

How well did you know this?

Not at all

Perfectly

Name the four types of coal

Anthracite
Bituminous
Soft
Peat

How well did you know this?

Not at all

Perfectly

Describe anthracite

Highest energy content and greatest store of carbon

How well did you know this?

Not at all

Perfectly

Describe bituminous

Forms as high pressure on lignite and is a poorer quality of anthracite

How well did you know this?

Not at all

Perfectly

Describe soft coal

E.g. brown coal
25-35% carbon
Lower energy potential and a major global source of energy

How well did you know this?

Not at all

Perfectly

Describe peat coal

An important carbon store of decaying trees, ferns and plants that has not yet turned to coal

How well did you know this?

Not at all

Perfectly

Volcanic activity
Increase in CO2
Loss of (1) from rocks
Increased temperature 
(2) of air
Increased rainfall from condensation 
Increase in (3)
More (4) are deposited on the ocean floor 
More carbon to be stored in (5) 
Cycle repeats

1 - carbon
2 - uplift 
3 - chemical weathering 
4 - ions 
5 - rocks

How well did you know this?

Not at all

Perfectly

Describe the oceanic carbon cycle

CO2 enters the ocean by diffusion on the surface

The volume of CO2 depends on wind, concentration of CO2 and water temperature

How well did you know this?

Not at all

Perfectly

Once the CO2 is dissolved in the sea, how does it enter the carbon cycle?

Physical carbon pump Biological carbon pump Carbonate pump

What is the physical carbon pump

Oceanic circulation distributes CO2 including thermigaline circulation so the colder the water the greater the potential for CO2 sequestration

What is thermohaline circulation

The movement of seawater in a pattern of flow dependency on variations of temperature which causes change in salt content and density

What is the biological carbon pump?

Phytoplankton photosynthesise sun light at the ocean surface taking up CO2 which then enters the food chain and eventually calcifies to make shells and rock

What does photosynthesis create?

Carbohydrates created using CO2 and H2O for growth also known as carbon fixation

What is a permafrost store?

Frozen land which releases carbon when it melts

Which flux to the atmosphere emits the least CO2?

Volcanic eruptions

Which flux to the atmosphere releases the most carbon dioxide?

Respiration and fire

How much CO2 is released from the combustion of fossil fuels and cement production?

7.8 petagrams of carbon a year

What flux inputs and outputs carbon in the atmosphere?

Input - combustion of fossil fuels | Output - photosynthesis

What fluxes input and output carbon in the lithosphere?

Input - sedimentary rock | Output - volcanic eruption

What fluxes input and output carbon in the biosphere?

Input - food web | Output - respiration

What fluxes input and output carbon in the hydrosphere?

Input - dead material | Output - phytoplankton photosynthesis

Name the stages of how carbon is released starting in the atmosphere and ending as magma

``` Atmosphere Transportation Deposition Subduction Magma ```

Describe how carbon is released in the atmosphere

CO2 reacts with water to form carbonic acid, this acid rain falls to the surface where it reacts with some geology such as limestone causing it to dissolve

Describe transportation from the atmosphere in the geological carbon release cycle

Calcium ions travel from rivers to oceans and combine with bicarbonate ions to form calcium carbonate and precipitate

Describe deposition from transportation in the geological carbon release cycle

Calcite sediment forms limestone when it is buried

Describe subduction from deposition in the geological carbon release cycle

The sea floor subducts under continental margins by tectonic spreading

Describe the final stage of the geological carbon release cycle

Rock rises as magma and is degassed as CO2 | Diamonds are the purest form of carbon formed up to 435 miles deep in the lower mantle

Describe terrestrial sequestration

Primary producers take carbon out of the atmosphere through photosynthesis and release it through respiration. When animals eat plants carbon becomes part of it’s fats and proteins. Micro organisms feed on waste material of dead organisms and so injest their carbon. After plant and animal death, tissue decomposes and adds carbon to the soil

Where is the greatest distribution of sources of carbon in ocean sequestration?

In the warmer areas mostly across the equator to the west of Africa

How many stages are there in thermohaline circulation?

Six

The first stage of thermohaline circulation: The (1) trade winds drive warm surface water to the (2) where it is warmed. The earth’s (3) moves the current north east towards (4)

1 - south east 2 - Gulf of Mexico 3 - rotation 4 - Europe

The second stage of thermohaline circulation: | When the water gets cold (1) forms so surrounding sea water gets (2) which increases its (3) and therefore sinks

1 - sea ice 2 - saltier 3 - density

The third stage of thermohaline circulation: | The (1) is recharged by extra cold, salty and dense water as it passes (2)

1 - current | 2 - Antarctica

The fourth stage of thermohaline circulation: | A (1) of the main current occurs northward to the (2) and the Western Pacific

1 - division | 2 - Indian Ocean

The fifth stage of thermohaline circulation: | The two branches (1) and rise as they travel (2) then loop back and come (3) towards Australia

1 - warm 2 - northward 3 - south-westerly

The final stage of thermohaline circulation: | The warmed surface waters continue to circulate around the globe so the cycle begins when current returns to the (1)

1 - North Atlantic

What is the carbonate pump?

Marine organisms use carbon to harden their shells so when they die they sink to the ocean floor where the soft matter decays and the shells form limestone

What would happen if there was no carbon causing the natural greenhouse gas effect?

The Earth’s surface would be 16 degrees Celsius colder

What is feedback in terms of changes in the carbon cycle?

Impacts of change on the carbon cycle as carbon is released from stores

Name the four main greenhouse gases

CO2 CH4 N2O Halocarbons

20% of CO2 will stay in the atmosphere for (1) years Accounts for (2)% of all greenhouse gases produced Concentrations in the atmosphere have increased by (3)% since 1850

1 - 800 2 - 89 3 - 30

CH4 will stay in the atmosphere for (1) years and makes up (2)% of greenhouse gases Emitted from (3) (4) times more powerful than CO2 Increased by (5)% since 1850

``` 1 - 10 2 - 7 3 - cattle farming 4 - 21 5 - 250 ```

``` N2O will stay in the atmosphere for (1) years Makes up for (2)% of greenhouse gases Emitted from (3) (4) times more powerful than CO2 Increased by (5)% since 1850 ```

``` 1 - 100 2 - 3 3 - engines 4 - 250 5 - 16 ```

``` Halocarbons constitute (1)% of greenhouse gas emissions Emitted from (2) (3) times more powerful than CO2 ```

1 - 1 2 - solvents 3 - 300

Since 1750, greenhouse gasses in the atmosphere has increased by how much?

25%

What four factors influence global temperature distributions?

Solar insolation Albedo effect Wind Ocean currents

Describe the albedo effect

Light surfaces reflect more heat than dark surfaces When the earth’a temperature dropped because of its position in orbit around the sun and tilt on its axis this caused the growth of ice sheds and so more heat was reflected and ice sheets expanded

What factors affect global precipitation distribution?

Solar insolation Pressure systems Collision of air masses Relief

How much carbon do phytoplankton sequester every year?

5-13 pentagrams

How much carbon does terrestrial photosynthesis sequester a year?

100-120 pentagrams

Describe the greenhouse gas effect

- Short wave solar radiation enters atmosphere - Short wave UV radiation passes through the atmosphere - Nearly 50% of short wave radiation is absorbed by the earth - Some short wave radiation is reflected back to space as long wave infrared radiation - Some long wave radiation is trapped by greenhouse gases and reflected back to earth

What are the components of healthy soil?

- Dark in colour and crumbly in composition - Worms present - Nutrients for plant growth - Sequesters carbon - Infiltration and retention of water

What does the store of carbon in soil depend on?

- Amount of organic carbon stored within the soil = inputs (animal waste and plant litter) - outputs (decomposition and plant growth) - Size of store depends on biomass

In the Northern Hemisphere, winter's (1) increases CO2 whereas spring's renewed (2) absorbs it, if winters become shorter then it is possible less CO2 will be released and climate change could be (3)

1 - organic decay 2 - plant growth 3 - neutralised

What carbon fluxes are happening faster because of fossil fuel combustion?

Carbon stored in the sea is thawing and so being released

What carbon fluxes are slowing because of fossil fuel combustion?

If tropical rainforests become less productive due to drier conditions then there will be slower growth therefore the flux to soil is slowed