Climate change

Climate change

1. greenhouse effect

   • The earth gains solar energy from the Sun.
   • This solar energy pushes through our atmosphere and heats up the oceans and land.
   • This heat is then radiated back (in other words we gain most of our heat from the ground as it acts like a radiator).
   • As the heat is radiated back out into the atmosphere some of it is trapped in greenhouse gases such as CFCs, CO2, and methane.
   • As we release more of these greenhouse gases into the atmosphere more and more heat is trapped and cannot escape. If more heat is trapped then temperatures will increase.

2. physical causes of climate change

   • Fluctuations in solar activity over time can increase or decrease global temperatures (1). This means that in different points in time the sun can give out more or less energy which alters temperature (1).
   • Volcanic eruptions can impact on global temperatures as large quantities of volcanic dust in the atmosphere shield the Earth from incoming insolation which lowers global temperature (1). For example, the eruption of Mount Pinatubo in 1991 caused a dip in global temperatures when 17 million tonnes of sulphur dioxide was released into the atmosphere (1). This reduced global sunlight by 10% and resulted in a 0.5% temperature decrease globally (1).
   • Large eruptions may also enhance the greenhouse effect and lead to global warming in some instances (1).
   • Milankovitch cycles (variations in the tilt and/or orbit of the Earth around the Sun) affect global temperature (1). More tilt means warmer summers and colder winters, less tilt has the opposite effect (1)
   • Melting permafrost from Arctic areas can release large quantities of the greenhouse gas, methane (1). This exacerbates the natural greenhouse effect, increasing global temperatures (1)

3. Human causes of climate change

   • The burning of fossil fuels produces carbon dioxide which leads to global warming (1)
   • Car exhausts, nitrogen fertilisers and power stations all produce nitrous oxide which increases the amount of greenhouse gasses in the atmosphere (1).
   • Worldwide deforestation also increases carbon dioxide levels, by reducing the storage of carbon (1).
   • CFCs found in fridges, air conditioning and aerosols contribute to global warming (1)
   • Increases in rice production and cattle farming contribute to atmosphere pollution (1). Because methane is a stronger greenhouse gas, small increases have a larger impact (1).

4. global impacts

   • Increased temperatures causing ice caps to melt so Polar habitats beginning to disappear (1
   • Melting ice causes sea levels to rise threatening coastal settlements (1
   • Global warming could also affect weather patterns, leading to more droughts and crop failures leading to problems with food supply (1)
   • Flooding could cause the extinction of species and more extreme weather, eg tropical storms. (1
   • Global warming could threaten development of developing countries as restrictions on fossil fuel use may be imposed to slow rate of increasing CO2 levels (1)
   • Loss of coral reefs – Increased CO2 causes the ocean to become more acidic and kills reefs. The tourist industry in reef areas such as the Maldives would also be lost and workers (e.g. scuba instructors) would become unemployed.

5. Local Impacts of climate change

   • In UK, tropical diseases like malaria may spread as temperatures begin to rise. (1
   • Tourism problems will increase as will be less snow in some mountain resorts and therefore people may not visit these areas. (1)
   • Higher temperatures may cause water shortages leading to droughts especially in Africa where wars could begin over this water shortage. (1)
   • Due to growing temperatures in the Southern part of the UK droughts become common in summer leading to hope pipe bans and farmers struggling to grow crops.(1)

6. solutions to climate change

   • Industries and domestic users of energy are encouraged to use it more efficiently through media awareness campaigns aimed at reducing (1 mark)
   • people are encouraged to walk, cycle, or use public transport rather than fossil-fuel powered cars (1 mark). bus lanes and cycle lanes designated to encourage people not to use their car (1 mark)
   • London Congestion Charge: drivers pay for driving in the Congestion Charge Zone to cut the pollution generated from exhaust fumes (1 mark)
   • Government tax is significantly reduced on vehicles with low CO2 emissions (1 mark
   • encourage people to holiday at home to reduce the number of aircraft journeys taken (especially short-haul flights) (1 mark)
   • recycle and reuse plastics and oil-based products (1 mark)
   • the UK Government now levy a charge of 5p for every carrier bag (1 mark)
   • Government grants to help home owners insulate house roofs and use more efficient heating systems (1 mark)
   • install solar panels on house roof to generate renewable energy (1 mark) or switch to an electricity supplier that supplies green electricity (1 mark)
   • developed countries switch from fossil fuels to alternative sources of energy in order to reduce the amount of CO2 in the atmosphere (1 mark) countries find new types of energy for example, biofuels (1 mark)