Both the frequency and intensity of wildfires are increasing worldwide as a result of climate change. If wildfires are out of control, they can have a devastating effect, endangering human lives and causing long-term damage such as biodiversity loss. To minimise this danger, the State Forests Department of Lower Saxony, Germany has installed a system for the early detection of wildfires.
In Lower Saxony there are 3 districts that are classified as high-risk areas for forest fires. These areas, located in the east of the state, have many reports of fires, especially during the summer months. In the past, early detection of forest fires was done by using fire monitoring towers. However, these became dilapidated over time and were replaced by a new camera-based monitoring system in 2009/2010 following the results of a feasibility study. The new monitoring system is a network of 17 monitoring sites covering a monitoring area of 10,000km², of which 4,000km² is forest.
The goal of the automated monitoring system is to detect forest fires quickly. It helps to minimize the time between the outbreak of the fire, automatic reporting of the fire by the system, confirmation of the alarm's validity by the control centre and the fire brigade's deployment to extinguish the fire. The faster this sequence takes place, the better can be prevented that wildfires grow to a large extent and become uncontrollable.
The camera system "Firewatch" uses originates from a method that was developed by the German Aerospace Centre (DLR) to detect comets in space. The technology measures the change in the grey scale of one image and compares it with other images. It could be adapted to the automated forest fire early detection system because the smoke that is produced when a fire breaks out changes the grey scale on the images so that it can be identified by the cameras. For this purpose, cameras were mounted on tall buildings such as transmission towers, which continuously scan the surroundings with 360 degrees and automatically trigger an alarm when smoke rises. The data is then forwarded by radio to a control centre in Lüneburg where the alarm is checked by human staff, who alert the nearest fire brigade if necessary.
Thanks to the "Firewatch" system, fires can now be detected more quickly. Consequently, in some cases, the ground forces requested can extinguish a fire only 20 minutes after it has been detected. The great benefit of the automated forest fire early detection system is therefore the speed of detection and subsequent rapid suppression of the fires. An example of this is the year 2018, in which 28 forest fires occurred in the monitoring area which were all quickly reported by the early detection system. As a result, no large fires were formed in any of the cases.
This good practice example shows how the increasing risk of wildfires in Germany due to climate change can be mitigated. The number of days with a high risk of forest fires on which the control centre had to be staffed has more than doubled in the last ten years, from an average of 50 days per year (2011-2017) to an average of 111 days per year (2018-2020). This means that an increased effort is required to prevent wildfires. However, a software update has significantly reduced the rate of false alarms in recent years. The more climate change progresses, the more we rely on technical solutions such as the automated "Firewatch" system, as this enables us to combat the consequences of climate change more quickly and effectively.
Niedersächsiches Landesforsten: Spezialseite Waldbrand
[Lower Saxony State Forestry: Special page on forest fires]