Energy
Case studies
,Key terms:
• Carbon sink - a carbon reservoir that absorbs more carbon than it releases (oceans, forests, soils)
• Carbon store - a place where carbon is captured and held both short or long term
• Carbon pool - a system that has the capacity to store or release carbon
• Carbon fixation - the incorporation of carbon into organic compounds by living organisms, chiefly by photosynthesis
in green plants
• Carbon sequestration - the removal and storage of carbon from the atmosphere in carbon sinks through physical or
biological processes (e.g. Photosynthesis)
• Thermohaline circulation - the movement of seawater in a pattern of flow dependent on variations in temperature
and salinity which gives rise to changes density - cold water and water with a high concentration of salt are the
most dense
• Phytoplankton - mostly microscopic, unicellular photosynthetic organisms that live in the upper sunlit layers of
oceans and other bodies of water
• Natural greenhouse effect - natural phenomenon that warms the Earth’s surface and lower atmosphere because
greenhouse gases absorb and emit infrared radiation that would otherwise escape into outer space
• Shortwave radiation - solar energy enters our atmosphere as shortwave radiation in the form of ultraviolet rays and
visible light
• Longwave radiation - solar energy heats up the ground and re-emits energy as longwave radiation in the form of
infrared rays - Earth emits longwave radiation because it is cooler than the sun and has less energy available to give
off
, Potential positive outcomes to stores and
Consequences to stores and pathways of changes in the carbon cycle
pathways caused by changes in the carbon cycle
• Increase in CO2 leads to warming of the atmosphere which will
cause hotter temperatures in some regions but colder in others.
Rise in temperature = more evaporation which will affect the
Climate
hydrological cycle • Increased tourism due to warmer locations –
• Drought and sudden shifts in weather patterns - more increasing the summer season
extreme, intense and frequent storm events.
• Thermal expansion and melting ice caps - sea level rise -
increase the impacts of storm surges.
• At risk species with low populations, limited climatic ranges and
restricted or patchy habitats could become endangered or even
• Increased CO2 may increase rate of
extinct.
photosynthesis, so more plant species will
• Artic and coral ecosystem biomes are the most vulnerable - lower
Ecosystems
flourish which could in turn increase the
oxygen levels, ocean acidification and rising temperatures could
biodiversity in the area. Also, some species
affect plankton growth which will alter the rest of the food chain.
could benefit from climate change as cool
• Soil health is influenced by stored carbon, which is important for
moist regions could provide habitats for more
ecosystem productivity.
species as temperatures increase.
• The increasing level of carbonic acid is bleaching coral formations
and thinning the shells of small animals.
• Increased precipitation in some regions means
Hydrological
• Increase in evaporation may increase precipitation and lead to
less risk of drought.
flooding as well as more intense and frequent El Nino events.
cycle
• Increased evapotranspiration and less
• Droughts - Australia, places near the equator
precipitation in other places means they are
• America - severe floods
less likely to flood.
, UK Energy Mix
o Electricity is generated by gas (42%), renewables (23%), nuclear (19%) then coal (9%). Reducing the UK’s carbon
emissions and increasing use of renewables, will increase the security and sustainability of our energy supplies.
o Electricity generation sources will vary due to the availability of renewable energy, cost of gas and coal,
environmental policies and our electricity price relative to countries we are interconnected with.
o An average unit of electricity in the UK (kWh) results in 360g of CO2 emissions and 0.007g of radioactive waste.
o Nuclear power stations account for 76.9% of EDF’s electricity generation, with coal accounting for 5.7%.
• Since 2010, 26 power stations have closed, which equates to 20% of the UK’s generation capacity.
• To provide a secure energy supply for the future, the UK needs a diverse and balanced energy mix - nuclear
power stations will contribute to this mix - reliable and most affordable large-scale, low-carbon energy source
currently available to the UK - uranium is a lot more abundant & concentrated with energy than fossil fuels.
o Consumes less energy now than 1970 despite 6.5 million more people living here - more efficient production & use.
o Around ½ of Britain’s gas supplies come from our own North Sea gas fields – the remainder is imported from many
sources including pipelines linking us with Europe, and liquefied natural gas (LNG) shipped in from around the world
- not dependent on one single infrastructure source to increase security.
o By 2030, renewables are expected to be by far the biggest source of energy used in electricity generation, making
up about 40% of the overall mix. Since 2010, in the UK there has been £52bn of investment in renewable energy.
o Around 61% of all the country’s fuel to produce electricity comes from overseas – not sustainable as the UK is
reliant on these countries to provide energy, increasing insecurity. Nevertheless, several countries are used to meet
energy demands with over 8 countries importing 54% by boat and the remaining 8.7% of 6 countries by pipe.
However, 12.5% of our total energy supply is from Russia which is considered a very politically unstable country.
