climate change geography

• Evidence for climate change

  Temperature trend

  Sea level rise

  Tree rings
• Natural causes of climate change

  Orbital changes

  Volcanic activity

  Solar output
• How do orbital changes cause climate change?

  Earth has elliptical orbit, so the sun isn't always in the middle
• How does volcanic activity cause climate change?

  Debris (ash) thrown into the atmosphere during an eruption blocks insolation, which increases temperature
• How does solar output cause climate change?

  The sun's output of energy isn't constant, and has been decreasing since 1978
• Human causes of climate change?

  Fossil fuels

  Deforestation

  Agriculture
• How do fossil fuels cause climate change?

  Accounts for over 50% of greenhouse gas emissions

  Releases CO2 into atmosphere (traps IR heat)
• How does agriculture cause climate change?

  Accounts for 20% of greenhouse gas emissions

  Produces large volumes of methane
• How does deforestation cause climate change?

  Trees absorb and store CO2.

  When trees are cut down, they releases CO2 and other greenhouse gases back into the atmosphere
• Ways to manage climate change through mitigation

  Alternative energy production

  Carbon capture

  Planting trees

  International agreements
• How does alternative energy production mitigate against climate change?

  Doesn't produce any greenhouse gas emissions

  But has low efficiency
• How does carbon capture mitigate against climate change?

  CO2 is compressed and stored underground

  But it requires lots of heat and electricity
• How does planting trees mitigate against climate change?

  Trees absorb CO2

  But trees need to grow for 50-100 years to make a significant impact
• How do international agreements mitigate against climate change?

  Limits countries on how many emissions they can emit

  But it's not compulsory to join
• 2 examples of international agreements to mitigate against climate change

  Kyoto protocol

  2015 Paris agreement
• Ways to manage climate change through adaptation

  Change in agricultural systems

  Managing water supply

  Reducing risk from rising sea levels
• How does changing agricultural systems adapt to climate change?

  Increasing irrigation in drier areas

  Introducing drought tolerant crops
• How does reducing risk from rising sea levels adapt to climate change?

  Flood barriers - eg. Thames barrier

  Building homes on embankments or stilts