Climate change is talked about a lot nowadays. Institutions, international advisory councils and state conferences worldwide are trying to find possibilities to comply with the 2°C-target to keep climate change in a tolerable dimension. This article is supposed to depict the correlation between climate change and increasing wildfire risk.
The Intergovernmental Panel on Climate Change (IPPC) is the best known institution dealing extensively and globally with climate change, its’ consequences but also adaptation and evasion strategies. Climate will become warmer for all considered scenarios. The current extreme scenario (RCP 8.5) is expecting a rise in temperature of 5.4°C until 2100, while the weakest future projection (RCP 2.6) is expecting to accomplish the 2°C-target until 2100. Additionally, the projection suggests a more frequent occurrence of extreme weather. This includes storm and extreme rain events as well as heatwaves and a higher number of subsequent summer days and tropical nights with resulting higher wildfire risks.
Especially in southern Europe the risk of wildfires will increase. But also the south and east of Germany will be affected more severely. This on one hand will become apparent by a more frequent occurrence of days with high fire risk and on the other hand by a longer fire season (Fig. 1). The future development of wildfire risk under certain scenarios has been modelled by the Potsdam-Institute for climate consequence research (PIK) and has been made publicly accessible through an online-tool. At KlimafolgenOnline.com one can get a good impression of how wildfire risk in Germany has developed and which projections can be made for the future. Overall, it has to be expected that also for Germany the wildfire risk will increase with progressing global warming.
In pre-industrial times wildfire events in Europe were determined mainly by the distribution of precipitation over the year, the occurrence of natural events (lightning without rainfall) as well as Neolithic slash-and-burn activities . From the 18th century onwards humans had the strongest influence . Several studies agree that future fire events will be influenced substantially by the rise in temperature [1, 8]. This counts as the most important cause variable because there is a correlation between temperature – especially temperature of the warmest and most humid month – and wildfire risk. Increasing temperatures can raise the wildfire risk through different factors. A change of climatic conditions can lead to changes of vegetation composition in a way that favors plants which are more susceptible to fire. Furthermore, high temperatures have an influence on the disposability of burning material as well as its’ ignitability. Wildfires are complex natural events and their driving factors are mutually dependent and often intensify each other. A holistic approach to this topic should be therefore aimed at [5, 7].
Lavorel et al. (2007) furthermore conclude that fires do not only influence vegetation but also climate itself. Fire and therefrom resulting changes in vegetation have strong influences on atmosphere, on biogeochemical cycles and on a variety of ecosystem services such as carbon fixation, soil fertility and the conservation of biodiversity. Currently forest and savanna fires are responsible for a significant amount of greenhouse emissions:
- Carbon-monoxide (CO)- and carbon-dioxide (CO2)- emission into the atmosphere: 1.7 - 4.1 billion tons per year – about 72 % of total emissions
- Methane (CH4): 39 mio. tons per year – about 10% of total emissions
- Nitrogen-oxides (NOx): 20.7 mio. tons per year
- Sulphur-dioxide (SO2): 3.5 mio. tons per year
- 86% of total global soot emissions
The change of local climate due to fire most likely is going to create climate preconditions, which themselves favor the development of fire and therefore also wildfires. Currently, great uncertainties still exist about the degree of such enhancement and buffer effects.
The Joint Research Center JRC – a research and knowledge service of the European commission – has been collecting data since 2004 about Europe-wide wildfire events and provides this data through a publicly accessible information platform online called EFFIS. Herefrom projections, changes and risks can be deduced, which can be the basis for joint international initiatives. The project started with six countries. In the year 2013 already 26 countries delivered data for the system, including three non-European countries. Participation is deliberate and there is no financial incentive. If subsidies of the EU for wildfire prevention measures in regions of high and medium wildfire risk are made use of (e.g. according to Art. 21c of the regulation 1305/2013 about the “subsidies for rural development” through the European Agriculture Fund for Rural Development EAFRD), it is obligatory to participate in the EFFIS statistic. From the increasing number of participating countries the importance and validity of the topic of wildfires in times of climate change can be derived.
- Badeck, F.-W. et al. (2004): Steigendes klimatisches Waldbrandrisiko – Eine Prognose bis 2050, in AFZ der Wald 2/2004
- Camia, A., Durrant, T. & San-Miguel-Ayanz, J. (2014): The European Fire DatabaseTechnical speficitations and data submission – Executive Report; verfügbar unter >PDF
- IPCC, Arbeitsgruppe 2: Folgen, Anpassung, Verwundbarkeit. Kapitel 23 Europa; verfügbar unter >Link
- Joint Research Centre: European Forest Fire Information System (2017); >Link
- Krawchuk Meg A. (2009): Global Pyrogeography: the Current and Future Distribution of Wildfire: >Link
- Kraus Daniel, Krumm Frank, Held Alex (2013): Feuer als Störfaktor in Wäldern. FVA-einblick 3/2013, S. 21-23
- Lavorel, S. et al. (2007): Vulnerability of land systems to fire: Interactions among humans, climate, the atmosphere, and ecosystems; verfügbar unter >PDF
- Pechony O. & Shindell D. T. (2010): Driving forces of global wildfires over the past millennium and the forthcoming century; >PDF