the carbon cycle

Question 1

how is carbon distributed between the global stores

Answer 1

Lithosphere: 99.9% of the earths carbon is stored in sedimentary rocks. 0.004% is stored in fossil fuels.

Hydrosphere: 0.04% of carbon is stored in the sea with most being held in the deep ocean and a small amount on the sea surface

Cryosphere: less than 0.01% of earths carbon with most being held in permafrost

Biosphere: 0.004% of earths carbon in living tissue

Atmosphere: 0.001% of carbon is held in chemical compounds; 40% more carbon now than in 1750

Question 2

name 6 flows in the carbon cycle and their influence on the magnitude of carbon stores

Answer 2

• photosynthesis: the uptake of CO2 by plants to produce energy thus transferring carbon form the atmosphere to the biosphere
• respiration: the breaking down of glucose by plants and animals which releases carbon dioxide and methane thus transferring carbon from the biosphere to the atmosphere
• decomposition: the breakdown of organisms by fungi and bacteria after death transferring carbon form the biosphere to the atmosphere and lithosphere
• combustion: burning which transfers carbon form the biosphere to the atmosphere
• carbon sequestration: the capture and holding of carbon caused by the the build up and compaction of dead tissue occurring in the ocean and forming sedimentary rocks
• weathering: the break down of rocks by acid rain (carbon and water vapor) which washes the molecules in to to the sea transferring carbon from the atmosphere to the hydrosphere and lithosphere

Question 3

how is carbon transfer effected on a spacial and temporal level

Answer 3

• on a spacial level different flows of carbon will occur at different frequencies depending on the scale
• on a temporal scale all carbon flows but sequestration can happen at a faster pace more frequently but sequestration will take millions of years

Question 4

2 wyas natural processes effect the carbon cycle

Answer 4

• wildfires: transfer large amounts of carbon from the biosphere to the atmosphere and decreased photosynthesis means less carbon is lost form the atmosphere. however they can encourage the growth of new plants
• volcanic activity: releases carbon stored in the earth as magma to the atmospheric store. recently volcanic activity releases less CO2 than human activity but have the potential to significantly disrupt the carbon cycle

Question 5

4 ways human processes effect the carbon cycle with examples

Answer 5

• hydrocarbon extraction: extraction and burning fossil fuels releases carbon into the atmosphere which would otherwise remain sequestered in the lithosphere.
• 2019: 89% of CO2 emissions were from burning fossil fuels
• farming practices: agricultural activities release carbon into the lithosphere and as the population increases these activities are practiced more; animal respiring and digesting, ploughing, growing rice.
• all the cows in Europe emit more carbon than all the cars
• 1kg of beef releases65x more CO2 than 1kg of potatoes
• deforestation: reduces the size of carbon stores. clearing forests by burning releases lots of carbon into the atmosphere.
• 3 billion trees trees in the Amazon were responsible for absorbing 1 quarter of all CO2 emissions in 2018
• deforestation rates have fallen between 2003 and 2015 by 75%

-land use changes: urbanization remove vegetation thus reducing urban storage and replaces it with concrete.
-concrete industries release 2.8 billion tones of carbon each year
-cement industry accounts for 7% of all anthropogenic CO2 emissions
-Urban areas occupy 2% of the world’s land mass, but
these areas account for 97% of all human caused global CO₂ emissions

Question 6

what is the carbon budget

Answer 6

-numerical threshold corresponding to carbon release and resultant temperature change

• tipping point is 1.5 degree increase
• total budget is 2 degrees
• conservation international estimates we’ve used 60% of the budget

Question 7

how does the carbon cycle affect the atmosphere and climate

Answer 7

• affects the amount of carbon containing gases in the atmosphere; greenhouse gases like CO2, methane
• greenhouse gases trap heat in the atmosphere and so as the amount of greenhouse gases increase so does the temperature; global warming
• global increases in temperate will affect the climate with an increase in intensity and frequency of extreme weather
• changes in climate increases and decreases

Question 8

how does the carbon cycle affect the lithosphere

Answer 8

• stored in sedimentary rocks, coal, oil,
• allows for plant photosynthesis and decomposition which recycles nutrients.
• changes could reduce the amount of carbon stored in land/lithosphere; warmer temperatures melt permafrost releasing carbon into the atmosphere, increase wildfire frequency
• desertification
• flooding, sea level rise
• loss of agricultural land

Question 9

how does the carbon cycle affect the hydrosphere

Answer 9

• stored in permafrost, ocean surface, calcium carbonate shells
• carbon is dissolved into the oceans directly form the atmosphere; used for photosynthesis and to form calcium carbonate shells
• increasing CO2 levels in the atmosphere can increase ocean acidity affecting marine life.
• global warming affects temperature sensitive organisms; phytoplankton cant survive high temperatures causing the population to decrease so less carbon is used for photosynthesis leaving more in the atmosphere

-ocean acidification
coral bleaching
melting of terrestrial ice

Question 10

7 countries who emit the most fossil fuel per person

Answer 10

-7 countries emit 10x of fossil fuel per person( Qatar, Kuwait, Trinidad and Tobago, Singapore, Estonia, Equatorial Guinea, Turkmenistan)