Carbon Cycle Flashcards
What was the name of the legal deal signed in 2015 about climate change?
COP21
How many countries signed COP21?
195
Why do oil prices fluctuate?
Geopolitical factors - if a country wants to block another or sanction another
Economic factors - supply and demand can cause oil prices to rise or fall
How has fracking in North America affected oil prices?
Caused them to fall dramatically
USA is largest energy consumer and so had to import a lot of oil and gas which was expensive
Domestic sources cut out transport costs, making prices fall
What is the geological carbon cycle?
The cycle of carbon between land, oceans and the atmosphere
What are the two types of carbon in the geological carbon cycle?
Geological carbon - stored in sedimentary and carbonate rocks
Biologically derived carbon - stored in shale, coal, etc
What are the two main ways of maintaining equilibrium in the carbon cycle?
Outgassing - carbon from the mantle is released by volcanos as CO2
Chemical weathering - where atmospheric CO2 combines with rain water to for carbonic acid which dissolves carbonate rocks
What is the bio-geochemical carbon cycle?
The transfer of carbon between living and chemical stores
What are the 4 main processes in the bio-geochemical carbon cycle?
Photosynthesis
Respiration
Decomposition
Combustion
How does the amount of carbon transferred from fossil fuel combustion relate to the amounts transferred naturally?
It is a very small percentage of natural transfer
However it is still enough to trigger effects such as climate change
Proves how delicate of an equilibrium the carbon cycle is in
What are the 3 ways carbon can be found?
Inorganic - rocks, etc
Organic - natural and plant material
Gaseous - found in atmosphere as CO2 and CH4
What is the biological carbon pump?
The way in which carbon is transferred from the ocean into the atmosphere and vice versa
What are phytoplankton?
Photosynthetic organisms that live in the surface layers of the ocean
Describe what is meant by the sequestration
The processes by which carbon moves through different stores and fluxes
How do phytoplankton sequester carbon?
They absorb CO2 for photosynthesis
They then grow and develop and use some carbon to make their carbonate shells
When they die they sink to the sea floor and accumulate where over millions of years they become carbonate rocks
How is carbon sequestered terrestrially?
Plants perform photosynthesis to convert CO2 into organic carbon
Primary consumers eat the plants
Secondary and tertiary consumers eat the primary consumers
The consumers die
Decomposition or non decomposition takes place
Carbon is transferred
How do mangroves sequester carbon from the atmosphere into the soil?
Photosynthesis to convert CO2 into organic carbon
Plant grows
Leaves and branches fall off
They decompose and are buried into the soil
This stores the carbon there
Compare the efficacy of soil as a carbon store in Tundra and Rainforest biomes
Rainforests have very deep soil and the trees are much larger so drop more organic matter. As a result, much more carbon can be stored here
in Tundra, much of the soil is frozen (permafrost). So, microbe activity only takes place in the very top layer of the soil.
Less decomposition can occur and as a result less carbon can be stored
Why do we need natural greenhouse gasses?
Because they absorb and re-emit heat back towards earth.
It keeps earth’s temperature more than 16 degrees warmer than it would be otherwise
This allows earth to sustain life
What percentage of CO2 emissions come from burning fossil fuels?
75%
What natural process is essential to maintaining the composition of the atmosphere? Explain why?
Photosynthesis
It pumps CO2 from the atmosphere into different stores such as the ocean or the soil
Without it CO2 concentrations would rise even quicker and global warming would be increased
What is primary productivity?
The rate at which an area produces biomass
Which biomes have the highest and lowest primary productivity?
Highest = Rainforest
Lowest = Desert or Tundra
What are the implications of fossil fuel exploitation?
Unbalancing the carbon cycle - It is in equilibrium, burning fossil fuels throws it off and can have long term impacts
Arctic Amplification - The arctic is warming at 2x the average global rate, this is causing snow melt and releasing trapped greenhouse gasses
Climate - Europe is getting much hotter year by year. Impacting the local ecosystems. More extreme weather patterns such as hurricanes
Hydrological cycle - The increased snow melt in certain areas could unbalance the hydrological cycle causing periods of extreme flooding or drought
What does the level of energy consumption depend on?
Lifestyle - more consumerism = more consumption
Climate - Extreme hot or cold = more consumption
Technology
Availability - more availability = more consumption
Demand - more demand = more consumption
What happens to energy consumption as countries become more developed?
Energy consumption increases
More people have more disposable income to spend on luxuries such as more hot water and air con/ central heating.
e.g Rising middle classes of Asia
What is an energy mix?
The proportion of a country’s energy consumption that comes from different stores
What are primary energy sources?
Energy sources consumed in their raw from
e.g fossil fuels such as petrol or coal
What are secondary energy sources?
Energy sources that can be used to generate electricity
e.g Wind or Solar power
What are domestic energy sources?
Energy sources that are produced and consumed in the same country
e.g North Sea oil for the UK
What’re overseas energy sources?
Energy sources that are imported from other countries
e.g UK imports lots of oil from Russia
Why might it not be beneficial to use overseas energy sources more than domestic ones
Creates an energy deficit
This creates a country more energy insecure as if the country they are importing from decides to increase prices they have no choice but to comply
e.g Uk is energy dependent on Russia. Ukraine invasion left the UK in a vulnerable position
What are Recyclable energy sources?
Energy that can be reused more than 1 time.
e.g Reprocessed uranium and plutonium from nuclear power
What are the 6 main factors that determine a country’s energy mix?
Physical availability
Cost
Technology
Political Considerations
Economic Development
Environmental Priorities
Describe the trends in both fossil fuel and energy consumption in the UK in recent years
Consumption is decreasing for both
However still too high to be sustainable and environmentally safe
Who are the 4 main players in securing energy pathways?
Energy TNCs
OPEC (oil-producing and exporting countries)
National governments
Consumers
Give examples of Energy TNCs (both old and new players)
Old: BP, Shell, Exxon/Mobil
New: Gazprom, Petrobas
What is the relationship between development and energy consumption?
As development increases so does energy consumption
What drove the rapid increase in global energy consumption since the 1990’s?
China’s rapid economic growth
What are energy pathways?
The way in which energy flows from its source to its consumer
How can disruption to shipping routes affect global oil prices? give a named example
Most oil is shipped on tankers
20% of these tankers pass the Straight of Hormuz
If this gets blocked then supply is shortened and price increases
Give an example of a political conflict that is said to involve oil
The USA and Russia’s involvement in the Syrian war
Many say it is to secure oil supplies and construct pipelines to Europe
Why are countries developing ‘unconventional’ fossil fuels? give an example of where this is occurring
To try and produce more domestic energy
Increases their energy security
e.g Canada exploiting tar sands
USA exploiting shale gas (by fracking)
Give some examples of ‘unconventional’ fossil fuels
Deep water oil
Tar sands
Shale gas
Oil shale
Who are the players in Canada exploiting tar sands?
Governments
Oil companies
Environmental pressure groups
Local communities
What are the costs and benefits of Canada’s tar sand exploitation?
Costs:
5-10 times more expensive than extraction oil
Very energy and water-intensive
Produces lots of toxic waste
Deforestation and loss of Peat bogs
Benefits:
Increases energy security
Can serve as a fuel stopgap while renewables become more available
Boosts local and national economies
Provides jobs for locals
How is the UK changing its energy mix?
By reducing reliance on imported fossil fuels:
Increasing renewables, (northern array wind farm)
Developing Nuclear energy (Hinkley Point C)
Reducing energy use (tech like LED bulbs)
Recycling more energy
What is the strike price?
The amount a government offers an energy company per MwH for a certain energy type
What are the pros and cons of using Biofuels instead of petrol?
Pros:
emits 80% less CO2 than petrol
In Brazil has cut CO2 emissions by 350 million tonnes
Reduces global warming
Cons:
Deforestation to plant the crops required
In Brazil, farmworkers were forced to grow sugar cane and were less able to grow food for their families
How carbon neutral are biofuels?
Not very
Plants need pesticides and fertiliser made from fossil fuels
Deforestation to grow crops removes carbon sinks
Some biofuels (like rapeseed oil) emit more carbon than petrol
What is CCS?
Carbon capture and storage
CO2 from coal power plants is compressed and transported underground
It is then injected into underground reservoirs e.g aquifers
Not financially viable to do on a large scale
