Forest growth

Assessment versions

Published (reviewed and quality assured)

• No published assessments

Rationale

Justification for indicator selection

Tree growth is controlled by complex interactions between climate and non-climate factors, with forest management having a significant effect. Trees have long been known to respond to changes in climate: variations in tree ring widths from one year to another are recognised as an important source of climatic information although difficult to interpret. Climate change is expected to influence forest composition and productivity. Increases in atmospheric CO₂, changes in temperature and the availability of water will affect the relative health and productivity of different species in complex ways. CO₂ has a direct impact on tree function and forest productivity. An increased concentration in the atmosphere stimulates photosynthesis and likely results in an increase in growth rates and leaf area, if other factors are not limiting. Increased temperatures generally speed up plant growth, rates of decomposition and nutrient cycling, though other factors like availability of water also influence these processes. Higher temperatures lengthen the growing season by advancing its start in spring and delaying its end in fall.

Climate change is expected to present several threats to forest growth and productivity such as increased frequency and severity of summer drought with impacts on drought-sensitive tree species, in particular on shallow, freely draining soils. Indirect effects on forest productivity are expected through changes to the frequency and severity of pest and disease outbreaks, increasing populations of damaging insects and mammals, and the impact of existing and new invasive species. Concurrent changes in nitrogen and sulphur deposition and increased levels of ozone pollution are also expected to have an impact. Nitrogen deposition can stimulate forest growth but it can also increase the susceptibility of trees to drought, diseases, pests and frost by causing acidification and nutrient imbalances, thus decreasing forest vitality. Based on the current understanding of these processes, the individual effects of climate and non-climate changes are difficult to disentangle.

Scientific references

• IPCC, 2007. Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Parry, K. L.; Canziani, O. F.; Palutikof, J. P.; van der Linden, P. J. and Hanson, C. E. (eds.), Cambridge University Press, Cambridge, UK.
• Forest Europe, UNECE and FAO (2011) State of Europe's forests, 2011: status & trends in sustainable forest management in Europe Ministerial Conference on the Protection of Forests in Europe, Forest Europe, Liaison Unit Oslo, Aas, Norway.

Indicator definition

• Forest area
• Volume of forest biomass

Units

• km²
• m³

Policy context and targets

Context description

In April 2013 the European Commission presented the EU Adaptation Strategy Package (http://ec.europa.eu/clima/policies/adaptation/what/documentation_en.htm). This package consists of the EU Strategy on adaptation to climate change /* COM/2013/0216 final */ and a number of supporting documents. One of the objectives of the EU Adaptation Strategy is Better informed decision-making, which should occur through Bridging the knowledge gap and Further developing Climate-ADAPT as the ‘one-stop shop’ for adaptation information in Europe. Further objectives include Promoting action by Member States and Climate-proofing EU action: promoting adaptation in key vulnerable sectors. Many EU Member States have already taken action, such as by adopting national adaptation strategies, and several have also prepared action plans on climate change adaptation.

The European Commission and the European Environment Agency have developed the European Climate Adaptation Platform (Climate-ADAPT, http://climate-adapt.eea.europa.eu/) to share knowledge on observed and projected climate change and its impacts on environmental and social systems and on human health; on relevant research; on EU, national and subnational adaptation strategies and plans; and on adaptation case studies.

Targets

No targets have been specified.

Related policy documents

• Climate-ADAPT: Adaptation in EU policy sectors
  Overview of EU sector policies in which mainstreaming of adaptation to climate change is ongoing or explored
• Climate-ADAPT: Country profiles
  Overview of activities of EEA member countries in preparing, developing and implementing adaptation strategies
• DG CLIMA: Adaptation to climate change
  Adaptation means anticipating the adverse effects of climate change and taking appropriate action to prevent or minimise the damage they can cause, or taking advantage of opportunities that may arise. It has been shown that well planned, early adaptation action saves money and lives in the future. This web portal provides information on all adaptation activities of the European Commission.
• EU Adaptation Strategy Package
  In April 2013, the European Commission adopted an EU strategy on adaptation to climate change, which has been welcomed by the EU Member States. The strategy aims to make Europe more climate-resilient. By taking a coherent approach and providing for improved coordination, it enhances the preparedness and capacity of all governance levels to respond to the impacts of climate change.

Methodology

Methodology for indicator calculation

Data stems from the report mentioned below.

Methodology for gap filling

Not applicable

Methodology references

• Forest Europe, UNECE and FAO (2011) State of Europe's forests, 2011: status & trends in sustainable forest management in Europe Ministerial Conference on the Protection of Forests in Europe, Forest Europe, Liaison Unit Oslo, Aas, Norway

Data specifications

EEA data references

• No datasets have been specified here.

External data references

• State of Europe's forests (dataset URL is not available)

Data sources in latest figures

Uncertainties

Methodology uncertainty

Not applicable

Data sets uncertainty

It is very difficult to separate the impacts of climate change on forests and forestry from non-climate influences (e.g. related to management) in observational data. Therefore, efforts to understand the impacts of climate change on forests and forestry are largely based on controlled experiments in laboratories and on small forest plots, and on model simulations.

Information on forest fires is collected in the European Fire Database at the JRC. The European forest fire database is an important component of the European Forest Fire Information System (EFFIS). Forest fire data are provided each year by individual EU Member States through several EU regulations, and additional data coming from other European countries have been checked, stored and managed by JRC within EFFIS. The quality of the data is high. A time series on forest fires exists back to 1980 for the five European countries most affected by forest fires. Currently, the database covers data from 22 countries in Europe and contains over 2 million individual fire event records.

Further information on uncertainties is provided in Section 1.7 of the EEA report on Climate change, impacts, and vulnerability in Europe 2012 (http://www.eea.europa.eu/publications/climate-impacts-and-vulnerability-2012/)

Rationale uncertainty

No uncertainty has been specified