Michael Norton and Jaana Bäck :
Earlier this month, the EASAC, which ‘provides a means for the collective voice of European science to be heard,’ confirmed the evidence that there are fundamental conflicts between the competing demands being made on Europe’s forests and the finite resources and services they can offer. Policy action is needed to reconcile these conflicts.
Nowhere is the conflict starker than between forests’ vital role as a carbon sink to mitigate climate change, and the increasing pressure to increase their use as a source of energy.
Using forests for energy is not carbon-neutral
The idea that forest bioenergy is carbon-neutral is widely used but it is highly simplistic and seriously misleading. Burning forest biomass releases significantly more CO2 than any fossil fuels it replaces and thus initially has negative effects on climate. How long this persists before net positive effects result are critically affected by the time it takes to reabsorb the carbon dioxide released when biomass is burned. We found scenarios ranging from a decade or so for forest by-products to several hundred years when additional trees from some forest types are extracted for bioenergy.
Since climate change is an urgent problem, we should realise that it is the carbon stocks in standing forests. that make the difference. Positive results of carbon uptake into forests after decades or centuries has little significance. It is thus critical to set sustainability criteria to define which types of forest biomass can make an effective contribution to meeting the Paris Agreement target to limit global warming to well below 2 degrees and aspire to 1.5 degrees. The European Commission has recognised this in its scientific assessments, but this approach has not yet been adopted in the Commission’s proposal for revision of the Renewable Energy Directive.
Even when positive impacts on climate can be ensured, biomass is relatively inefficient in mitigating climate change and this should logically be considered when choosing between renewable energy options involving much lower carbon technologies such as wind and solar. This should also be reflected in the renewable energy subsidies.
The most climate-friendly option when using wood is to create high-quality products that store carbon for long time periods. However, in the EU, only 1/5 of all wood harvested goes to these long lasting products. From a climate perspective, this calls for changes in the way we use wood.
Forests slipping through the carbon-accounting net
The EU land use policy looks at the annual carbon flow between the atmosphere and forests, and whether forests are a net sink or source of carbon into the atmosphere. Currently, the carbon that is removed from the atmosphere annually by the EU’s forests is equivalent to about 10% of the member states annual fossil fuel emissions. The EU’s standing forests help to moderate warming of the planet.
Under international rules emissions from biomass combustion are not calculated on the energy sector but should be accounted for in the land use sector at the point of harvesting. In the Land Use, Land Use Change and Forestry (LULUCF) proposal that is up for debate at the European Parliament and the Council there are dangers that forest reference levels will be set according to inappropriate specifications. The result could be shifting emissions from the energy sector to the land use sector without any real reduction in negative climate impacts. Accounting should reflect possible changes in harvesting levels and the use of forest biomass. Otherwise, there will be no accounting of biomass emissions.
Protecting biodiversity and climate go hand in hand
In mitigating climate change, biodiverse forests have several benefits. Biodiversity increases productivity and resilience against climate change and other environmental stresses and underpins the ecosystem services provided by forests. So in order for European forests to optimally contribute to climate change mitigation the diversity of forests should be upheld and enhanced.
Biodiversity has a value on its own right and EU countries have committed in international agreements to enhancing protection of its threatened and endangered species. The small areas of remaining old-growth and virgin forests (currently only 2% of Europe’s forests) need to be protected and other forests managed with greater attention paid to biodiversity. Adapting forest management practices to enhance biodiversity and ecosystem resilience can also provide a steady source of income to forest owners, as has been proved with examples of continuous cover cultivation.
Our analyses indicate that only by adopting a coherent and holistic approach will it be possible for EU policymakers to deliver the optimal social, environmental and economic benefits from this finite resource our forests provide.
(Professor Michael Norton is the Environment Programme Director at the European Academies Science Advisory Council (EASAC). Professor Jaana Bäck specialises in forestry at the University of Helsinki).
