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Forestry and Climate Change - issues and potential indicators. For UNECE/FAO Team of Specialists, Edinburgh, 21-22 May 2007 Simon Gillam, UK. Forests and climate change. 1. Carbon - how do trees affect the carbon balance? 2. How else do trees impact on climate?
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Forestry and Climate Change - issues and potential indicators For UNECE/FAO Team of Specialists, Edinburgh, 21-22 May 2007 Simon Gillam, UK
Forests and climate change • 1. Carbon - how do trees affect the carbon balance? • 2. How else do trees impact on climate? • 3. How does changing climate affect trees and forest habitats? Simon Gillam for UNECE/FAO ToS May 2007
1. Carbon balance • Trees sequester carbon as they grow • Trees are a store of carbon • Changes to soil carbon - positive and negative • Carbon released by forest fires or deforestation • Wood fuel can replace fossil fuels • Wood products can replace steel, concrete, etc • What else? …more later Simon Gillam for UNECE/FAO ToS May 2007
2. Some other impacts of forests • If climate hotter, then shade from trees (e.g. streets and towns) becomes more valuable … but also forests trap heat. • If more storms, forests can reduce impacts of flooding • If water shortages, forests may be a shield against evaporation? ... but conifers also take up more water (not broadleaves?) Simon Gillam for UNECE/FAO ToS May 2007
3. Some effects of climate change • Warmer climate - more rapid tree growth • Changes to natural ranges for some species • Insects and diseases move into new areas • More storms - more windblow • What else? Simon Gillam for UNECE/FAO ToS May 2007
Carbon balance - what value/tonne? • Per tonne carbon or per tonne CO2 • Social cost of carbon: • wide range of estimates for current value • carbon trading price not a good proxy • should it increase over time? • or should it be higher in the short run, because of claimed urgency of action? • discounting to get Net Present Value? Simon Gillam for UNECE/FAO ToS May 2007
Carbon balance - woodfuel • Common approach is just to estimate fossil fuel carbon saved. • This assumes that the woodfuel is carbon neutral. • Carbon emissions from woodfuel similar to fossil fuel; so need to consider whether the carbon sequestration balances the emissions. • Depends on where the woodfuel comes from... Simon Gillam for UNECE/FAO ToS May 2007
Carbon balance - SRC • Short rotation coppice • Carbon sequestered balances carbon burned • Additional benefit from carbon stored while growing • Carbon stored in roots and stumps • Possible carbon losses from soil disturbance, and from machinery for harvesting and transport. Simon Gillam for UNECE/FAO ToS May 2007
Carbon balance - existing forests • In short run, reduces carbon stored in forests • If part of good management (e.g. thinning), rate of carbon sequestration / hectare may be little affected (fewer trees left, each growing more) • If bringing neglected woodlands into management, may remove wood that would otherwise decay, and improve tree growth • But if badly managed, may remove growing trees that would otherwise sequester carbon in the future - worse than using fossil fuels. Simon Gillam for UNECE/FAO ToS May 2007
Indicators - how to capture all this? • Carbon - sequestration rate, as well as amount stored? • Wood fuel - quantity used, by source - JWEE? • Other wood products - sustainable use? • Anything for other impacts of forests (e.g water - ecosystem services)? • For impacts on forests, are forest damage indicators sufficient? Simon Gillam for UNECE/FAO ToS May 2007
Public Opinion Survey Q5 • How much of an impact do you think climate change will have on the UK? • Large impact • Slight impact • No impact at all • Don't know Simon Gillam for UNECE/FAO ToS May 2007
Public Opinion Survey Q6 • Would you agree or disagree with the following statements about the ways in which forests and woodlands in the UK can impact on climate change? • (1) strongly agree • (2) agree • (3) neither agree or disagree • (4) disagree • (5) strongly disagree • don't know Simon Gillam for UNECE/FAO ToS May 2007
Public Opinion Survey Q6 • Trees are good because they remove carbon dioxide from the atmosphere and store it in wood • Cutting down forests and woodland makes climate change worse, even if they are replanted • Using wood for fuel is better for climate change than using fuels such as coal and gas • Using wood for fuel makes climate change worse because it releases carbon dioxide • Using wood for building is better for climate change than using materials such as concrete and steel. • The UK could offset all its greenhouse gas emissions by planting more trees Simon Gillam for UNECE/FAO ToS May 2007
Public Opinion Survey Q7 • Do you agree or disagree with the following statements regarding how UK forests and woodlands should be managed in response to the threat of climate change? • (1) strongly agree • (2) agree • (3) neither agree or disagree • (4) disagree • (5) strongly disagree • don't know Simon Gillam for UNECE/FAO ToS May 2007
Public Opinion Survey Q7 • There is nothing that anyone could do that would make any difference • No action is needed; let nature take its course • A lot more trees should be planted • Trees should not be felled in any circumstances, even if they are replaced • Different types of trees should be planted that will be more suited to future climates • More information should be provided about the ways in which wood can be used to lessen our impact on the environment Simon Gillam for UNECE/FAO ToS May 2007