The Carbon Cycle and Energy Sercurity Flashcards
what is the geological carbon cycle?
a natural, long-term cycle that moves carbon between land, ocean, and atmosphere
what does the geological carbon cycle involve and what does this create?
involves a number of chemical reactions which creates new stores which trap carbon
how do chemical processes maintain a dynamic equilibrium?
- volcanic eruptions lead to a rise in temperature and hence increased evaporation/ moisture in the air
- increased acid rain weathers rocks and creates bicarbonates which are deposited as carbon on ocean floor
how is a state of dynamic equilibrium maintained in the geochemical carbon cycle?
carbon production and absorption are balanced
what do biological and chemical processes determine in the carbon cycle?
how much carbon is stored and released
what are the four processes involved in the biogeochemical carbon cycle?
- photosynthesis
- respiration
- decomposition
- combustion
how is photosynthesis involved in the biogeochemical carbon cycle?
removes CO2 from the atmosphere for plant growth
how is respiration involved in the biogeochemical carbon cycle?
releasing CO2 into the atmosphere
how is decomposition involved in the biogeochemical carbon cycle?
breaking down organic matter releasing CO2 into soil
how is combustion of biomass and fossil fuels involved in the biogeochemical carbon cycle?
releasing CO2 into the atmosphere
what do biogeochemical processes do for the carbon cycle?
continuously transfer carbon from one store to another
another word for carbon production?
outgassing
another word for carbon absorption?
sedimentation
examples of outgassing? (3)
- volcanism
- metamorphism of carbonate rocks at a subduction zone
- calcium carbonate deposition
example of sedimentation? (3)
- animal skeletons/ shells compact to form limestone
- decaying vegetation into coal
- sands and clays from rivers compact to form sandstone/ shales
how is carbon absorbed through sedimentation?
shells and skeletons of marine creatures extract carbon from seawater and phytoplankton. their remains accumulate on the seabed whereby the process of diagenesis, they compact into inorganic limestone.
what is diagenesis?
the long-term process by which sediments are changed into sedimentary rocks
how is carbon produced through outgassing?
volcanic activity at subduction zones causes gases such as CO2 to be released
why is so much CO2 released through volcanism?
CO2 is the least soluble of volcanic gases and so is degassed earlier than others and so are abundant
what is the largest carbon store?
the mantle
what is the largest known carbon store?
sedimentary rocks
what are carbon fluxes?
the exchange between stores of carbon
what is the biological carbon pump?
the process by which marine organisms sequester carbon from the ocean surface and convert it to organic matter
what do phytoplankton do in ocean carbon cycling?
photosynthesis, removing carbon from atmosphere and into the food web
what is the marine carbon pump?
the process of carbonate material accumulating on the seabed. occurs in the deep ocean
what is the physical carbon pump?
diffusion and transfer of CO2 in ocean currents. it occurs in the deep ocean and is global
what does the thermohaline circulation do in carbon cycling in oceans?
maintains the physical carbon pump by locking carbon in the deep ocean.
how does the thermohaline circulation lock carbon in the deep ocean?
- cold, saline water is more dense and so sinks
- warm water is drawn down from the surface
- water is drawn across from the Tropics
- cold water is drawn up to be warmed
what are the impacts of climate change on the biological carbon cycle? (4)
- slow/ stop the thermohaline circulation
- gulf stream slowed by 30% since 2000
- glacial melt water in Atlantic changes salinity which reduced deep ocean store
- carbon bleeching
what is carbon bleeching?
when marine organisms lose their ability to absorb carbon due to increase in pH in the ocean
what happens as a result of glacial melt water in the Atlantic ?
it changes the salinity of the ocean which reduces deep ocean carbon store increasing atmospheric concentrations
what is a primary producer?
a living organism that produce energy from sunlight through photosynthesis
how do primary produces transfer CO2 from the atmosphere to terrestrial store?
they use chlorophyll in chloroplast cells to convert CO2 and water into carbohyrdates
how do primary produces release CO2 ?
respiration
what is carbon fixation?
the conversion of CO2 to cellulose
what is carbon sequestration?
when CO2 is removed from the atmosphere and stored in biomass
what type of environment sequesters the most carbon?
tropical forests
why do tropical forests sequester the most carbon?
due to high temprature and rain which encourages decay
what type of environment sequesters the least carbon and why?
tundra due to low temprature, however carbon can be stored for millenia
where are 30% of the worlds primary producers?
tropical rainforests
where is the largest terrestrial carbon sink?
tropical rainforests, due to them having 30% of the worlds primary producers
what will remove CO2 storage/ absorbation
deforestation for farming and mangrove clearance
what could be the implications of a 2*C temprature rise on the climate?
temperate/ tropical zones experience stronger storms
why would a 2*C temprature rise lead to stronger storms in temperate or tropical zones?
more heat and moisture in the air
what could the implications of a 2*C temperature rise on ecosystems?
habitat change will mean 10% of land species face extinction
what could be the implications of a 2*C temperature rise on the hyrological cycle?
- humidity levels in the atmosphere increase
2. rivers dry in regions (reduced precipitation)
what is an energy mix?
the different primary energy sources of a country
what are the factors affecting a countries energy mix? (6)
- physical availability
- cost
- technology
- politics
- economic development
- environmental priorities
how does physical availabilty affect the UK’s energy mix
in the 1950s-70s, UK was a global leaderin nuclear tech. but lost momentum after discovery of oil and gas reserves
how does cost affect the UK’s energy mix?
north sea oil expensive to extract
how does technology affect the UK’s energy mix?
150yrs coal reserves left but technological and environmental concerns make extraction unrealistic
how do policial considerations affect the UK’s energy mix?
political concerns over fracking and nuclear energy
how does physical availability affect Norway’s energy mix?
HEP natural choice due to mountainous terrain and plentiful rainfall
how does cost affect Norway’s energy mix?
HEP costs are low
how does technology affect Norway’s energy mix?
drilling technology allowed Norway and UK to develop North Sea oil and gas extraction
how do political considerations affect Norway’s energy mix?
government prevents foreign companies from owning private energy sources
how does environmental considerations affect Norway’s energy mix?
2015: Norway committed to 40% reduction in green house gases by 2030
how do environmental considerations affect the UK’s energy mix?
green deal conservation and insulation schemes abandoned in 2015
what is an energy pathway?
the flow of energy between producer and consumer
what are the two types of recyclable energy?
- nuclear
2. biofuels
what are the two types of renewable energy?
- tidal
2. wind
what are the two types of renewable energy?
- Hydroelectric power
2. solar
`what are the advantages of nuclear energy? (4)
- no emissions
- reduced reliance on imports
- reliable
- not suseptable to price fluctuations
what are the advantages of biofuels? (4)
- carbon neutral
- easy to source
- cheap
- workable in low income countries
what are the disadvantages of nuclear energy? (4)
- construction and decomissioning costs
- risk of disaster
- waste
- rough states
what are the disadvantages of biofuels? (2)
- surronding environment damaged
2. deforstation
what are the advantages of tidal power? (6)
- clean
- no bi products
- produce great amounts of energy
- inexpensive to maintain
- predictability of high and low tide
- recreational lakes
what are the disadvantages of tidal power? (2)
- not always constent as it depends on strength/ flow of tides
- need suitable sites
what are the advantages of wind energy? (4)
- clean
- available in every country
- anywhere on any scale
- large scale (7% of energy in germany)
what are the disadvantages of wind energy? (2)
- visual pollution
2. not always windy
what are the advantages of HEP? (4)
- large scale (1/5 of the worlds electricity)
- drinking water
- flood control
- mini dams possible
what are the disadvantages of HEP? (4)
- effects on wildlife
- ressettlement of populations (1.2 million for three gorges dam)
- conflict (south east anatolia project)
- cities/ towns flooded (Hasankeyf)