5 - Ecosystems

• Mitigation


  Strategies that deal with the cause of climate change by reducing or preventing the greenhouse gases which cause it and protecting carbon sinks
• Adaptation


  Strategies that respond to the impacts of climate change and try to make populations less vulnerable
• Carbon capture and storage

  1. Capture CO2 from emission sources

  2. Store CO2 safely underground in sedimentary rock
• Methods of mitigating climate change

  • Alternative energy production
  • Carbon capture, usage and storage
  • Planting trees
  • International agreements
• Alternative energy production


  • Renewable energy sources (wind, solar, geothermal, wave, tidal, biomass) reduce greenhouse gas emissions
  • Renewable energy is becoming cheaper and more competitive
• Solar energy


  • Photovoltaic solar energy generated 11.7% of UK's electricity in 2018
  • A typical home saves over a tonne of CO2 per year from using solar energy
• Carbon capture and storage could provide 10-55% of the world's total carbon mitigation until 2100
• The UK Government granted £4.2 million to support a carbon capture and usage scheme in 2019
• Deforestation occurs at a rate of 13 million hectares per year globally
• A $40 billion investment in reforestation and payments to landholders for conservation each year from 2010 to 2050 could increase forest carbon storage by 28%
• The EU aims to reduce global emissions by at least 40% below 2010 levels by 2030, and by 60% by 2050
• Some countries can afford to mitigate climate change more than others, and some are considered more responsible for causing climate change than others
• Climate-smart agriculture


  • Moving production to another location due to changing temperatures and extreme weather
  • Increasing irrigation in areas due to changing precipitation
  • Changing the crops and varieties grown and the time of year they are planted
• The cost of adapting to climate change is more difficult for poorer subsistence farmers
• Managing water supply


  1. Reducing demand (water-efficient devices)

  2. Increasing supply (desalination plant)
• The desalination plant in Beckton, London requires a lot of energy and its carbon emissions need to be offset by a biofuel electricity plant
• Londoners consume 167 litres of water each day compared to the national average of 146 litres
• London faces the challenge of climate change: summers will get drier and winters will get wetter
• Summers will get drier and winters will get wetter (Chapter 15)
• Two ways water can be managed

  1. Reducing demand

  2. Increasing supply
• Reducing demand


  • As Mayor of London (2008–16), Boris Johnson developed a Water Strategy to reduce London's water demand
  • By 2030, all London homes should have been offered a free retrofit package of water-efficient devices (Figure 4.17), including aerators
• Increasing supply


  • Thames Water opened a desalination plant in Beckton in 2010 to increase water supply
  • Water is taken from the River Thames at low tide (when it is least salty)
  • A process called reverse osmosis is used to produce drinking water for 400,000 homes
  • The plant requires a lot of energy (enough to power 8,000 homes), so carbon emissions need to be offset by a biofuel electricity plant
• Fieldwork: Get out there!
• Investigate the impact that mitigation (such as solar panels as an alternative energy source) and adaptation (such as not building on a floodplain for flood prevention) strategies have on the physical environment in your local area

  1. Decide what evidence of mitigation and/or adaptation you could survey

  2. Suggest where you could carry out your fieldwork

  3. Devise an environmental survey to assess its impact on the physical environment

  4. Explain why an environmental survey is qualitative data
• Mitigation


  Strategies to reduce the causes of climate change
• Adaptation


  Strategies to adjust to the effects of climate change
• Agricultural systems need to adapt in the future
• How agricultural systems can change to cope with climate change


  • Figure 4.16
• The 'Water Strategy' has been established in London to reduce water demand
• Other ways to reduce water consumption in the home


  • Not listed in Figure 4.17
• Water efficiency measures in Figure 4.17

  • Tap aerators (saving for whole house)
  • Dual flush
  • Shower timers
  • Aerator showerheads
• The water efficiency measure in Figure 4.17 with the greatest impact on managing London's water supply is tap aerators
• Existing flood defence schemes such as the Thames Barrier may need to change due to climate change
• Both mitigation and adaptation are needed to manage climate change
• Impact of water-efficient devices installed in London homes


  • Figure 4.17
• London is currently well protected against rising sea levels by the Thames Barrier
• A 50 centimetre rise in sea level would increase the risk of the Thames Barrier being breached once every 100 years, rather than the original design of once every 1,000 years