Facts about wildfires
Science addresses fundamental questions about wildfires both in Germany and globally
During summer, reports of wildfires surge, especially in Mediterranean countries, Canada, the USA, and Central Asia, where fires often spiral out of control. In recent years, the frequency of wildfires has also increased in Central and Northern Europe, including Germany. Human-induced climate change is exacerbating the problem by making vegetation more flammable. In Germany, the initial spark for many fires is often caused by human activities. Time to look at the facts in context.
Are there more fires in Germany compared to the past?
Wildfire situation in Germany compared to international standards?
Where does the initial spark come from?
Why is the situation worsening in Germany?
Who are the stakeholders in German forestry and what are their concerns?
What role does the Global Fire Monitoring Center play?
Are there more fires in Germany compared to the past?
Yes, there are more fires in Germany now compared to the past. According to statistics from the Federal Ministry of Food and Agriculture, between 1991 and 2017, an average of about 680 hectares of forest burned each year. This includes the fires of 1992, during which a particularly dry spring led to 4,000 hectares of forest burning.
However, the situation has worsened significantly in recent years due to prolonged droughts from 2018 to 2022.Over 2,000 hectares of forest burned in 2018 and 2019, and in 2022, the area affected by fires exceeded 3,000 hectares. This is more than double the average from 1991 to 2017.
Fires on agricultural lands are not statistically recorded and receive less media attention. In Brandenburg and Bavaria, field fires spread to settlements in 2022 and 2023. These fires were caused by factors ranging from overheated machinery to sparks sprayed from the cutting mechanism of harvester hitting stones.
Wildfire situation in Germany compared to international standards
The Forest Condition Report by the Federal Ministry of Food and Agriculture highlights significant drought damage to Germany's forests. Since 2018, approximately 500,000 hectares have been affected by climate change, including storm damage. This equates to five percent of Germany's total forest area, or slightly less than the area of the Black Forest. The damage incurred over the last five years is estimated at around 20 billion euros.
This information is also based on comprehensive satellite monitoring by the Sentinel-2 satellite of the European Copernicus Earth Observation Program.
Canada, with over 200 million hectares, has the largest forest area after Russia and Brazil. Unlike Germany's forests, which are largely human-made cultural landscapes, Canada's forests are natural. In contrast, Germany's forest area is only about five percent of Canada's total.
While Canada saw an average of two million hectares of forest affected by fire annually in the 2010s, the area burned surged to over 18 million hectares in 2023. A study estimated that the fires in 2023 released nearly three gigatonnes of CO2, which is five times the total CO2 emissions from fossil fuels in Germany for that year and represents eight percent of global emissions for the same period.
Although CO2 emissions from vegetation fires have historically been reabsorbed by regrowing vegetation, climate change has introduced a new dynamic. If changing climate conditions prevent the same forest or open land vegetation from regenerating and if soils degrade, the CO2 that would normally be sequestered remains in the atmosphere. In these cases, fires result in a net increase of CO2 in the atmosphere.
A recent study published in Nature Ecology and Evolution analysed nearly 90 million satellite images of global fire activity over the past 20 years. It revealed that extreme vegetation fires are now about twice as frequent and intense as they were two decades ago. Notably, the six most extreme fires have occurred in the last seven year.
Where does the initial spark come from?
In Canada and Siberia, lightning causes about 20 to 30 percent of wildfires. These fires are natural and occur at intervals ranging from decades to centuries. However, intentional or negligent arson also plays a role.
In Germany, natural causes contribute only a small percentage of wildfire ignitions. The primary causes vary from year to year. In 2023, intentional arson was responsible for about 3 percent of forest fires, while in 2022, it accounted for nearly 36 percent. Negligence caused about 10 percent of forest fires in 2022 and 14 percent in 2023. The causes of 42 percent and 77 percent of burned areas in 2022 and 2023, respectively, could not be determined.
Why is the situation worsening in Germany?
Climate change is exacerbating extreme weather conditions, including intense rainfall over short periods and prolonged droughts. The latter increase the risk of vegetation fires, which are more challenging to manage than under previous, more stable climate conditions.
Specifically, spruce monocultures—comprising about a quarter of Germany’s forest—are particularly vulnerable to the effects of rising temperatures. Drought-stressed spruce stands are prone to infestations by bark beetles. Without intervention, these pests can spread rapidly. The accumulation of deadwood in the forest, combined with drought, contributed to the difficulty in controlling wildfires in the Saxon-Bohemian Switzerland and Harz regions in 2022.
Who are the stakeholders in German forestry and what are their concerns?
Since the 18th century, Germany has managed its forests with a focus on sustainability. Climate change has only become a prominent issue in recent decades.
Forestry administrations follow the federal sustainability strategy to maintain the various functions of the forest landscape for future generations. This strategy includes:
- Harvesting wood as a renewable resource
- Protecting settlements from noise, floods, landslides, and avalanches
- Providing recreational spaces
- Enriching biomass for CO2 storage
- Maintaining and increasing biodiversity, such as by leaving deadwood for habitat
- Experimenting with different tree species that may better withstand climate change
- Forest owners – both private individuals and public entities such as municipalities, states, and the federal government – take several measures to prevent wildfires. These actions include selecting appropriate tree species, determining suitable locations for vegetation, thinning out forests, creating lighter corridors. Additionally, for firefighting purposes, they construct access roads and establish water reservoirs.
Fire departments respond to wildfires once they have ignited. In Germany, a well-developed network of forest paths and roads facilitates easier access for fire departments with their vehicles. Based on recent experiences, fire departments are increasingly equipping themselves with smaller off-road vehicles and hand tools to effectively and quickly tackle ground fires in challenging terrain.
The science of fire ecology examines whether forest management could incorporate fire management strategies by drawing on examples from natural fires in Canada, Siberia, and the Global South. This research aids fire departments and forestry administrations in developing new strategies to adapt to the effects of climate change.
What role does the Global Fire Monitoring Center play?
The Global Fire Monitoring Center, based at the Max Planck Institute for Chemistry, plays a key role in translating research into practice and coordinating efforts among stakeholders. It explores methods to sustain the functions of cultural forests in Germany amidst challenges like drought and wildfires.
Summary by Tobias Beuchert on July 17, 2024