Carbon Flashcards
ADD IMPACTS OF POOR OCEAN HEALTH AND FUTURE UNCERTAINTIES OF CLIMATE CHANGE
Which are the biggest and smallest carbon stores and how many PgC of carbon can they store?
Biggest: Lithosphere - 100,000,000 PgC
Smallest: Atmosphere - 750 PgC
How many times bigger is the hydrosphere store than the atmosphere?
50x bigger
What 2 elements make up the biogeochemical carbon cycle and which one is faster?
Geological and biological cycle, biological is faster
What are the 2 fast biological interactions?
- Atmosphere –> hydrosphere
- Atmosphere –> terrestrial biosphere
What is the flux when carbon moves from atmosphere to surface ocean, what rate does it occur at, and at what rate does the opposite flux occur?
Diffusion, 92 PgC/year, 90 PgC/year
What is the flux when carbon moves from atmosphere to surface ocean through phytoplankton and what % of global carbon sequestration does this account for?
Photosynthesis, 50%
What is the flux when vegetation sequesters carbon from the atmosphere, at what rate does this occur and how many times faster is it than respiration?
Photosynthesis, 123 PgC/year, 1000x faster
What is the flux when carbon moves from vegetation to soil store and at what rate does this occur?
Decomposition, 50 PgC/year
How is carbon in soil store released back into atmosphere?
Fungi/detritivores break it down and release CO2 via respiration
What is the fast biological to slow geological interaction?
Hydrosphere –> lithosphere
What is the process when carbon stored as dissolved CO2 or marine biota moves from surface ocean to deep ocean, at what rate does this occur at, and by what 3 fluxes does this occur through?
Downwelling, 90 PgC/year
1. Biological pump
2. Carbonate pump
3. Physical pump/thermohaline circulation
How much carbon is stored as surface sediment and what process occurs to transform it into CaCO3 or fossil fuels?
0.2 PgC/year, lithification
What process involves carbon moving from the lithosphere to hydrosphere then back to lithosphere again and at what rate does this occur?
Chemical weathering, 0.8 PgC/year
What is the slow geological to fast biological interaction?
Lithosphere –> atmosphere
Via what process can carbon move from lithosphere to atmosphere by anthropogenic activity and at what rate does occur?
Combustion, 35 PgC/year
What is the flux when carbon moves from lithosphere to atmosphere, at what rate does this occur, and how does it occur?
Volcanic outgassing, 0.15 PgC/year, continental crust undergoes subduction so carbon trapped within CaCO3 rocks released as CO2
Describe the process of limestone formation
- Formed from shale particles from marine organisms e.g. crabs
- Organisms die and shell fragments precipitate and sink to ocean floor
- Organic material buried under other organic materials and is lithified to limestone due to increase in pressure/compaction
Describe the process of shale formation
- Organic material precipitates onto ocean floor and covered in mud
- Material is embedded into mud layers and mud exposed to intense heat/pressure so is lithified to form shale
Describe the process of fossil fuel formation
- Organic material precipitates onto ocean floor and covered in mud
- Material decays anaerobically
- If organic material added at faster rate than it decays, becomes a fossil fuel
Describe the full process of chemical weathering to volcanic outgassing
- (Chemical weathering explanation)
- Breaks down rock into component ions e.g. Ca2+ which are transported to ocean in solution
- Ions react with bicarbonate to form CaCO3 which sinks to ocean floor and undergoes lithification to become sedimentary rock
- (Volcanic outgassing explanation)
What are the first 2 steps of an ocean pump PAD?
- Moves carbon from the surface ocean to the deep ocean
- This maintains the diffusion gradient, enabling more carbon to be sequestered from the atmosphere
Describe the process of the biological pump
- Phytoplankton use sunlight to convert CO2 into organic matter via photosynthesis
- Carbon enters food chain when phytoplankton eaten by small fish and some carbon released via respiration
- Marine biota die and precipitate to ocean floor - majority eaten by deep sea consumers or transported by ocean currents
- 0.1% carbon reaches the ocean floor to be stored as surface sediment and compacted into the lithosphere to become CaCO3
Describe the process of the carbonate pump
- Dissolved CO2 and bicarbonate ions generated from chemical weathering held in surface ocean
- Shellfish use carbon to make their shells comprised of CaCO3 and die so CaCO3 precipitates to ocean floor
- If reaches ocean floor, lithified/compacted to form limestone as part of slow geological cycle
Describe the process of the physical pump/thermohaline circulation
- At poles water is colder which leads to sea ice formation
- Increased density of water due to lower temp. and increased salinity
- Nutrient-rich, CO2-containing water sinks (downwelling)
- Colder water can hold more carbon so current picks up more carbon/nutrients
- Current gets closer to tropics so surface water gets warmer, less dense, and rises so upwelling of nutrient-rich waters
- Carbon released back into atmosphere which helps to maintain balance
What are 2 ways that coral reef ecosystems can balance the carbon cycle?
- Sequester carbon via photosynthesis
- Base of food web so maintain levels of biodiversity and ensure strength of biological pump
Describe the process of ocean photosynthesis and how it regulates the composition of the atmosphere
- Phytoplankton/coral use dissolved CO2 in oceans and sunlight to photosynthesise and convert it into carbohydrates for growth
- Maintains diffusion gradient so CO2 levels in atmosphere remain stable as carbon enters biological pump
- Supports maintenance of natural GHE
How do coral reef ecosystems regulate the carbon cycle by being the base of the food web?
- Increase biodiversity so biological pump can function and carbon can work its way up food chain
- More carbon move from surface to deep ocean and diffusion gradient maintained
- Less carbon remaining in surface ocean and atmosphere (small, sensitive store)
What are the 2 ways the terrestrial (vegetation) store regulates the carbon cycle?
- Photosynthesis/respiration
- Decomposition
How does terrestrial photosynthesis/respiration regulate the carbon cycle?
Plants sequester carbon from atmosphere and convert into biomass and photosynthesis 1000x faster than respiration - maintains low CO2 conc. in atmosphere and supports natural GHE
How does terrestrial decomposition regulate the carbon cycle?
Detritivores/fungi break down leaf litter so biomass becomes part of humus soil store - decreases CO2 conc. in atmosphere and supports natural GHE as carbon now held in larger store
By the end of the 19th century, what had UK % forest cover decreased to and what did it increase to after forestry conversions were set up?
From 80% to 10%, 14%
Between 1990-2020, how much afforestation took place in China?
0.63 million km2
What are 2 positives of afforestation?
- Globally, programmes could remove 191 GtC from atmosphere by 2100
- Economic benefits (for every $1 spent on afforestation, $9 in benefits e.g. employment)
What is a negative of afforestation?
Often uses monocultures so less diverse ecosystem and less resilience so would become carbon source if whole forest was destroyed
What are 3 impacts of deforestation on the carbon cycle?
- More wildfires
- Increased EGHE
- Forest dieback (positive feedback mechanism)
What is the case study for deforestation creating more wildfires?
Amazon Drought 2016
What caused the 2016 Amazon drought, by what % did the no. of fires increase by, and how many trees were killed as a result?
El Nino, 36% increase, 2.5 billion trees killed
What did the 2016 Amazon drought turn the Amazon rainforest into and how many estimated tonnes of CO2 did it generate over the following 3 years?
Carbon source, 495 million tonnes
What is the linked evaluation for deforestation creating more wildfires and unbalancing the carbon cycle?
Longer term carbon store in soils is pyrogenic carbonaceous carbon produced from biomass by wildfires
How does forest dieback happen as a result of decreased forest cover due to drought (positive feedback mechanism)?
Less forest cover so trees prioritise growth over health so decreased immunity to pests/pathogens so decrease in canopy layer so more soil baking and less infiltration so more hydrological drought so less forest cover
How does the conversion of grasslands create an unbalanced carbon cycle?
Ploughing causes immediate loss of CO2 from top soils so grasslands become net emittors of carbon, removed grasses and shrubs also can’t pull CO2 from atmosphere
How many tonnes of CO2 would avoiding grassland conversion prevent from being released?
35 million tonnes
What impact does grassland conversion have on humans (application)?
Savanna grasslands are home to Africa’s Big 5 and contribute to Africa’s GDP through tourism
What is the linked evaluation for grassland conversion creating an unbalanced carbon cycle?
Conversion is slowing due to growing challenges associated with water insecurity (irrigation) which will make it more expensive to convert and maintain production
What are 3 impacts of forest loss on humans?
- Increased food insecurity in Indigenous populations
- Increased exposure to malaria
- Increased exposure to zoonotic diseases
How does forest loss cause increased food insecurity in Indigenous populations?
Bushmeat e.g. bats is an important food source as main source of protein and livestock farming isn’t available - less amino acids so malnutrition and decreased immunity to disease
How does forest loss cause increased exposure to malaria?
Ground is less shaded so increased exposure to sunlight so increased standing water (heated by solar radiation) so perfect breeding ground for mosquitoes so increased malaria
By what % did malaria transmission increase in Malaysia after a 10% increase in deforestation?
3% increase
How does forest loss cause increased exposure to zoonotic diseases?
Human encroachment on habitats of forest-dwelling animals caused forced displacement of animals so more contact with human pops. so more likely to transmit disease
What % of new infectious diseases originated in forest-dwelling animals and what is an example?
60%, Ebola
What % of carbon do soils store?
20-30%
How do marshes act as carbon sinks?
Waterlogged all year round so soils are largely anaerobic so slower decomposition so carbon held in dead plant material remains intact rather than being broken down
How do peatlands act as carbon sinks?
Dead organic matter added to soil in waterlogged conditions which occurs at faster rate than decomposition so carbon held in dead plant material remains intact rather than being broken down
How many tonnes of carbon do the Scottish peatlands hold?
1.7 billion tonnes
How much more carbon do mangroves store than rainforests?
5x more carbon
Describe the positive feedback mechanism of permafrost
Increased thawing of permafrost so more decomposition by microbes so CO2 released via respiration and CH4 released from permafrost so increased EGHE so increased thawing of permafrost
Describe the negative feedback mechanism of permafrost
Increased thawing of permafrost so more decomposition via microbes so increased soil nutrient levels so more boreal forest growth more CO2 sequestration via photosynthesis so decreased EGHE so decreased thawing of permafrost
How does the draining of wetlands lead to them becoming carbon sources?
Draining exposes organic material to O2 so more decomposition/respiration by microbes/detritivores so becomes carbon source
What % of the world’s wetlands have been lost over the last 300 years (draining wetlands leads to them becoming carbon sources)?
87%
What is the linked evaluation for draining wetlands leads to them becoming carbon sources?
Natural wetlands emit CH4 so contribute to GHE and expected that global warming will increase release of CH4
How much larger is the warming power of CH4 compared to CO2 (draining wetlands leads to them becoming carbon sources LE)?
80x larger
Define energy security
Uninterrupted availability of energy sources at an affordable price
Define long-term energy security
Timely investments to supply energy in line with economic development/environmental needs
Define short-term energy security
Ability of energy system to react properly to sudden changes in balance between energy in demand and supply
What % of the global energy mix do non-renewables account for?
80%
What % of France and the USA’s energy mix is carbon fuels and therefore which country is more energy secure long term?
France: 50%
USA: 82%
More secure = France
What % of France and the USA’s energy mix is nuclear energy (recyclables) and therefore which country is more energy secure long term?
France: 41%
USA: 8%
More secure = France
What % of France and the USA’s energy mix is foreign and therefore which country is more energy secure short term?
France: 46%
USA: 15%
More secure = USA
What are the 6 factors that influence energy consumption?
- Physical availability
- Technology
- Economic development
- Cost
- Climate
- Environmental priorities
How does physical availability influence energy consumption and what are the case studies for places where primary energy sources are more/less available?
More available supply with low extraction costs so decreased price so more consumption
More available: Saudi Arabia - abundant supply of oil at shallow depth
Less available: North Sea - oil deeper in the ocean
How does cost influence energy consumption (related to conflict)?
Increased distance/complexity to transport gas supply so increased cost + price so decreased consumption
What is the case study for cost influencing energy consumption (related to conflict)?
War in Ukraine disrupted Europe’s gas supply from Russia so European countries seeking gas elsewhere - Qatar liquid natural gas transported via containership
How does technology influence energy consumption?
If have available technology for extraction, more access to primary energy source so more supply so increased availability/affordability so more consumption
What % of Iceland’s energy needs does it meet via HEP/geothermal energy and how much per capita energy consumption does Iceland have?
80% of energy needs, highest per capita energy consumption
How does economic development influence energy consumption?
Larger GDP so more income so more energy-intensive lifestyles (e.g. cars in China) and higher relative income means consumers less sensitive to price changes so more consumption
How does climate influence energy consumption and what is the case study for it?
Extremes in climate will increase energy consumption, Iceland has highest per capita usage due to heating
How do environmental priorities influence energy consumption?
Decrease consumption: Many countries agreeing to transition away from fossil fuels to meet climate targets
Increase consumption: More investment into renewables will increase price ST but decrease price LT so more consumption
By what year is the UK aiming to reach its net zero carbon target and by what % has the price of photovoltaic panels decreased by since 2010 (environmental priorities influencing energy consumption)?
2050, decreased 80% since 2010
Who are the 3 key players in an energy pathway?
- OPEC
- Governments
- Consumers
What is OPEC and how is it a key player in the energy pathway (includes application)?
Cartel of 14 oil-producing nations, in 2021 estimated that OPEC member countries account for over 80% of world’s proven oil reserves and control oil prices by restricting supply to increase revenue
What is a linked evaluation for OPEC being a key player in the energy pathway?
Influence of OPEC may be declining due to global transition away from fossil fuels to meet climate targets (UK aiming to reach net zero carbon target by 2050)
How are governments a key player in the energy pathway, what year did the UK gov. ban new petrol/diesel car sales, and why?
Influence the energy mix so have influence over demand, 2023, to decrease demand for oil-based fuel and to transition to electric cars
What is a linked evaluation for governments being a key player in the energy pathway?
Government’s influence reduced by level of energy security - high % of imports/foreign energy = reduced ability to change energy mix without disruption
How are consumers a key player in the energy pathway?
Usually passive players who adapt to changing national conditions with regards to energy pricing
What is a linked evaluation for consumers being a key player in the energy pathway?
Fracking in UK was banned in 2019 after pressure groups took Quadrilla in Lancashire to court after fracking caused tremor, also increasing influence through investment in household renewables e.g. solar panels
Who are the 3 largest producers of coal, who are the largest consumers of coal, and what does this mean in terms of mismatch between supply and demand (includes app.)?
3 largest producers: China (46%), Indonesia, Australia
3 largest consumers: China (51% of global consumption but produces 90% of coal it uses), India, USA
Not much of a mismatch between supply and demand
Who are the largest oil producers, who is oil-thirsty and how many barrels of oil do they produce a day?
North America and OPEC, Europe, under 2,000 barrels/day
Why is there a mismatch in the global supply and demand of oil?
Oil is only fossil fuel used in transportation so deeper global market - Europe has large demand but limited supply
Which 2 countries dominate both production and consumption of natural gas, how is natural gas transported, and what is the case study for this?
USA and Russia, pipelines, Russian gas to Europe
What % of natural gas consumed in Germany was imported from Russia and why did this become an issue recently?
60%, Russia-Ukraine conflict reduced imports of gas
What are the 3 energy pathways, how could they be prone to disruption, and what is a piece of application for each?
- Pipelines - geopolitical issues - Gazprom cut gas to Ukraine in 2014 as Russia said Ukraine owed money
- Shipping lanes - human error - Suez Canal blockage 2021
- Road - weather - Hurricane Katrina 2005 blocked roads and left oil production at 42%
What are the 3 unconventional fossil fuels and what are their case studies?
- Tar sands - Canada
- Shale gas - USA
- Deep water oil - Brazil
What is a social cost and benefit of Canadian tar sands (includes application)?
Cost: Communities living near tailing ponds have been warned that water is contaminated
Benefit: Provides enough oil to power more than 3 million Canadian homes
What are implications of Canadian tar sands for the carbon cycle?
Contaminated water kills birds/fish so weakens carbonate pump and decomposition so more CO2 in atmosphere
What is a social cost and benefit of USA fracking for shale gas (includes application)?
Cost: Expensive process to power machinery used to inject water
Benefit: 2015 shale gas accounted for 25% of US output so helped to increase energy security
What are implications of USA fracking for shale gas for the carbon cycle?
Negative impacts on local habitats/biodiversity so less photosynthesis/decomposition so more CO2 in atmosphere
What is a social cost and benefit of Brazilian deep water oil?
Cost: High extraction costs due to depth at which oil is located so need hi-tech drilling equipment/offshore oil rigs
Benefit: Provides 90% of Brazil’s oil
What are implications of Brazilian deep water oil for the carbon cycle?
Produces flammable byproducts which causes explosions and oil spills which decrease biodiversity so less photosynthesis/decomposition so more CO2 in atmosphere
What is a benefit of HEP (renewable)?
Generate electricity through flowing water driving turbines/generators that produce electricity
What is the case study for HEP benefits, how many gigawatts of energy does it have the potential for, and what % of the pop. has access to electricity?
GERD in Ethiopia, 6 gigawatts, 45% of pop. so increases energy security and helps drive economic growth
What are 2 costs of HEP (renewable)?
Environmental: Requires areas to be flooded which destroys habitats of aquatic species so reduced biodiversity
Political: Impacts water security of other nations e.g. Ethiopia/Egypt
What % of fish species in the Amazon River have decreased by as a result of HEP construction?
25%
What is a benefit of wind energy (renewable)?
Uses wind to drive turbines that spin and create kinetic energy which is converted into electrical energy
How many new jobs could investment into onshore wind in the UK create by 2030?
27,000
What is a cost of wind energy (renewable)?
National Planning Policy framework states that proposals for onshore wind can’t go ahead until objectives by local community have been addressed and concerns about noise pollution from local comm.
What is a benefit of solar energy (renewable)?
Allows for conversion of endless solar energy to electricity through photovoltaic panels
By 2100, what % of Africa’s energy mix is estimated to be solar energy?
50%
What is a cost of solar energy (renewable)?
High reliance on consistent sunlight for optimal photovoltaic output
What % of the global population live in 70 countries where there is true potential for solar energy?
20%
What is a benefit of nuclear energy (recyclable)?
Waste product from energy conversion can be recycled and reused in a different reactor and releases no CO2 emissions into atmosphere
In how many years is it believed that the entire grid could be powered by nuclear energy in the US?
100 years
What is a cost of nuclear energy (recyclable)?
Negative public perception of safety of nuclear energy and extremely expensive
What year was the Fukushima disaster and what level was the nuclear meltdown?
2011, level 7 nuclear meltdown
What are primary biofuels and how much less carbon than gas do they produce as a % (recyclable)?
Fuel wood and other organic materials used in their unprocessed form for electricity, 60% less carbon than natural gas
What is a cost of primary biofuels and what is an example of a company who does this?
Deforestation, Drax supply woodchips by deforesting ancient woodland
What are secondary biofuels and how many full-time employees will it create in Brazil by 2030 (recyclable)?
Liquid biofuels such as ethanol derived from processing of biomass, 63,000 employees
Between 2010-2015, by what % did use of imported palm oil in vehicles in the EU increase by and therefore how many times bigger are carbon emissions than the fossil fuels being replaced (cost of secondary biofuels)?
8% to 46%, 3x more emissions
What is carbon capture, what is the largest carbon capturing-plant, what does it turn carbon into, and how many tonnes of CO2 does it remove per year (radical technology)?
Capturing carbon released through fossil fuel combustion and burying it deep underground, ORCA in Iceland, stones, 36,000 tonnes/year
What is a challenge of carbon capture?
Can’t be certain long term that carbon will stay underground and not seep out back into atmosphere and expensive
What do hydrogen fuel cells do (radical technology)?
Combines H2 and O2 to produce electricity, heat, and water
What is a challenge of hydrogen fuel cells?
H2 doesn’t exist in large quantities in its natural form so needs to be split from H2O which is energy-intensive so GHG released in process
What is a benefit of electric cars (radical technology)?
Can be powered by renewables which reduces CO2 and PM 2.5 emissions which provides social benefit in terms of health
What is a challenge of electric cars?
Ethical issues as children as young as 7 working in cobalt mines to get cobalt used for car batteries so increased inhalation of cobalt dust and potential for lung disease
What is the case study for changing energy mix?
UK
By what % has energy rise in the UK transport sector increased by since 1970 and what is the LE for this (changing energy mix)?
50% increase, clean air zones in Birmingham and congestion zones in London
What is the major change in UK energy consumption and what is the LE for this?
Rapid decline in use of coal and void left behind filled with natural gas, first coal mine in 30 years opened in Cumbria in 2022
By 2030, what type of energy is expected to be the biggest source of energy used in electricity generation and what % of the energy mix will it make up?
Renewables, 40%
What are the 2 hard adaptation strategies to changing climactic conditions and would they be used in developed/developing countries?
- Resilient agricultural systems = developed
- Flood risk management = developing
What is a benefit of resilient agricultural systems (hard adaptation strategy)?
Genetically modified drought-intolerant species help resistance to climate change and may help with CO2 sequestration
What is a challenge of resilient agricultural systems?
High costs from indoor/intensive farming and more expensive technology
What is a benefit of flood risk management (hard adaptation strategy)?
Planting more trees increases afforestation and carbon sequestration e.g. Velvet and flood defenses reduce flood risk
What is a challenge of flood risk management?
Landowners may demand compensation for afforestation and constant maintenance is needed on flood defenses
What are the 2 soft adaptation strategies to changing climactic conditions and would they be used in developed/developing countries?
- Water conservation and management = developing
- Land use planning = developed
What is a benefit of water conservation and management (soft adaptation strategy)?
Less resources used and less groundwater abstraction so less hydrological drought
What is a challenge of water conservation and management?
Efficiency/conservation can’t match increased demands for water
What is a benefit of land use planning (soft adaptation strategy)?
Building restrictions in vulnerable flood plains and low-lying coasts so decreased risk of flooding from sea level rise
What is a challenge of land use planning?
Abandoning high-risk areas is unfeasible in megacities such as Bangladesh so unable to escape flood risk
What are 3 mitigation strategies used to reduce climate change?
- Carbon taxation
- Afforestation
- Carbon capture
How does carbon taxation mitigate climate change?
Sets a minimum price companies have to pay to emit CO2 and raises price of more carbon-intensive fuel so consumers more likely to use cheaper, less polluting option
Which country’s government is in favour of carbon taxation and what did the price per tonne of CO2 released start at in 2019?
Canada, $20 per tonne of CO2 released
What is the linked evaluation for carbon taxation mitigating climate change (includes application)?
US gov. continue to subsidise fossil fuel to around $30bn/year which is counter-productive to what carbon taxation aims to achieve
How does afforestation mitigate climate change?
Called for by the Kyoto Protocol - National Trust aims to plant 20mil trees over next decade to remove increasing amounts of CO2 from atmosphere
What is the linked evaluation for afforestation mitigating climate change?
Evidence from scientific research shows that ancient woodlands sequester far more CO2 than young woodlands due to leaf mass - trees have to be allowed to mature to reach full sequestration potential
