3.7.1 Mitigation

Tutorial about mitigating climate change

Mitigating climate change mainly involves reducing the amount of greenhouse gases that are entering the atmosphere. We can attempt this by:

  • reducing human emissions of greenhouse gases, e.g. by burning less fossil fuels, or by capturing the greenhouse gases released in buring these fuels and storing the gases somewhere
  • increasing the uptake of carbon dioxide by plants, soils and the oceans.

 

To achieve the first of these means addressing a wide range of human practices that emit greenhouse gases. The following table is adapted from a table in the IPCC 4th Assessment Report:

 

Sector Some currently available mitigation options Some options that could be available before 2030

Energy supply

  • Power stationImprove the efficiency of energy supply so less energy is wasted
  • Switch from using coal to gas
  • Nuclear power
  • Use renewable heat and power (hydropower, solar, wind, geothermal and bioenergy)
  • Use combined heat and power technologies (which waste less energy)
  • Use Carbon Capture and Storage (e.g. the storage of carbon dioxide removed from natural gas)
  • More & better Carbon Capture and Storage
  • Advanced nuclear power
  • Advanced renewable energy, including tidal and wave energy, and better solar energy systems

Transport

  • Increase use of more fuel efficient vehicles, including hybrid vehicles (which have both a petrol and an electric engine)
  • Use cleaner diesel vehicles
  • Power vehicles with biofuels
  • Switch from road transport to rail and public transport
  • Walk and cycle more
  • Plan new developments to reduce travel distances
  • Improved biofuels
  • More energy-efficient aircraft
  • Advanced electric and hybrid vehicles
Car exhausts

Buildings

  • Efficient lighting and use of natural light
  • More efficient electrical appliances, heating and cooling devices
  • Improved insulation
  • Buildings designed to make good use of sunlight for heating and fresh air for cooling
  • Alternative refrigeration fluids
  • Intelligent meters that provide feedback and control
  • Solar panels integrated in buildings

Industry


  • Introduce more efficient electrical equipment
  • Recover heat and power from machinery
  • Recycling logoRecycle more materials
  • More energy-efficient practices

Agriculture

  • Improve crop- and grazing-land management to increase soil carbon storage
  • Restore cultivated peaty soils and degraded lands to a more natural state (so they store more carbon)
  • Improve rice cultivation techniques
  • Better livestock and manure management to reduce methane emissions
  • Improve nitrogen fertilizer application techniques to reduce nitrous oxide emissions
  • Use more energy-efficient farming practices
  • Improved crops yields

Forestry/forests

  • Afforestation and reforestation (grow more trees)
  • Reduce deforestation (cut down fewer trees)
  • Better forest management
  • Use forestry products for bioenergy to replace fossil fuel use
  • Develop tree varieties that yield more energy when used as a fuel
  • Develop tree varieties that are better at taking up carbon dioxide

Waste management

  • Increase recycling of waste
  • Recover methane from landfill sites
  • Incinerate (burn) waste and use the energy generated
  • Compost organic waste
  • Methods to optimize methane oxidation

Original IPCC table (table SPM.3)

From the table above it seems a lot could be done to mitigate climate change. Unfortunately, things are not so simple. There are many reasons why we are not doing enough of the above.

 

Exercises

  1. From your experience, do you think we are doing enough of the things listed in the table above? Think about the reasons why we may not be doing enough. For example, if you think people are not making a big enough effort to use public transport instead of cars and lorries, why do you think this is? You may also think about ways to improve the situation.
  2. There are many efforts - by governments, non-governmental organisations, companies and individuals - which try to encourage us to change our lifestyles so that we emit less greenhouse gases. Write down any you can think of or have tried yourself (such as 'walk to school' campaigns). Or, search the web for such initiatives. Take one scheme and decide which sector it fits into (e.g. transport, energy supply). Write down in your own words what the scheme is trying to achieve (e.g. encouraging more recycling, or buying more locally-produced food).

 

Emissions targets

Governments have a key role to play in climate change mitigation. They can develop policies and schemes to encourage people and businesses to adopt climate change mitigation measures. Many of the world's governments have set targets to help this. In the UK, The Climate Change Act 2008 established a new approach to managing and responding to climate change in the UK. The Act created a legally binding target to reduce the UK’s emissions of greenhouse gases to at least 80% below 1990 levels by 2050. This is one of the most challenging targets set by a national government.

Perhaps the most well-known climate change target is the Kyoto Protocol. Adopted in 1997 as a protocol to the United Nations Framework Convention on Climate Change (UNFCCC), the Kyoto Protocol makes a legally binding commitment on participating countries to reduce their greenhouse gas emissions by 5% relative to 1990 levels, during the period 2008-2012. There are 193 participants to the protocol, including 37 of the worlds's industrialised nations, together with the European Community, but the USA is not one of them.

The Kyoto Protocol was seen as a first step towards reducing greenhouse gas emissions, but globally, emissions of carbon dioxide are increasing, not decreasing, as this 2011 news item reports. Some scientists believe that to avoid the worst consequences of climate change (so-called 'dangerous climate change') we must limit global warming to 2°C over pre-industrial levels. This would require a reduction in greenhouse gase emissions compared to 1990 levels of around 80%, as the UK is committed to.