A background of carbonized air completes the blackened landscape from which stand out hundreds of scarlet green ferns already ten centimeters high. A fire ravaged at the beginning of June a plot of the forest massif of Fontainebleau, in Seine-et-Marne, leaving behind hundreds of maritime pines on the ground. Others, browned, are still standing. Not for a long time. Asphyxiated at their roots, they will collapse in less than a year. Barely a month later, this steep area, long used as a cobblestone quarry, has regained a certain splendor born of the contrasts that cover it. A little high up, overlooking the forest and out of sight, we understand why the bivouacs at the origin of the fire pitched their tents on these rocks surrounded by trees. During the weekend, they lit a campfire to spend a nice evening with friends. “They surely thought they had the situation under control,” said Morgane Souche, environmental project manager at the National Forestry Office (ONF), because most of the time, campers are in good faith. But in this forest, even after being extinguished, the fire continues to smolder under this peat soil composed of a complex of organic matter. No trace of smoke, even less flames, yet the damage is only beginning. Generally, the first visible traces only appear after two days when the fumes emerge from the ground. This time, it was an airline pilot who alerted the emergency services. Often, it is the walkers who act as whistleblowers. If the visitors, more than 15 million per year is as much as at Disneyland Paris, are at the origin of almost all the fires, they are also the main lookouts of the massif. The responsiveness of the firefighters also makes it possible to channel the risks: thanks to their action, only 1.2 hectares were affected during this episode.
Rising temperatures and fires, the losing equation
Operations that continue to increase because global warming and the risk of fire go hand in hand. If, in the North, all outbreaks of fire are of anthropogenic origin, that is to say linked to human activity, and very rarely due to lightning, high temperatures are an aggravating factor. “Hatching is facilitated during heat waves. When it is 40°C for example, this is a data that was recorded at 2 meters high and under shelter. But on the ground, we easily reach 60°C. discarded butt then ignites quickly”, recalls Romaric Cinotti, head of forest fire assistance in the southern zone of Météo-France. Dry vegetation, excellent fuel, then facilitates the spread of fire. But the waves of heat waves, like those that crossed France in June and mid-July, are more frequent but also earlier than yesterday. “Before, in the North, there were only five really risky days during the summer. Now, it’s up to two weeks of very strong vigilance”, observes the meteorologist. If the danger is disproportionate to that which threatens the southern departments, the fires that occurred in Sweden in 2018 and in Siberia in 2019 are turning points to be taken into account.
“We always have the IPCC report with us in the trunk,” says Guillaume Larrière of the ONF. In their latest opus, the climatologists point out that in a probable scenario, the climate of the Fontainebleau forest will be similar to that which currently exists in Aquitaine by 2070. It could even become Mediterranean if the most pessimistic scenario materializes. “The risk of a big fire is therefore our obsession”, slips Morgane Souche of the ONF, whose institution works hand in hand with the Departmental Fire and Rescue Service of Seine-et-Marne (SDIS 77 ) for nearly ten years. A close relationship, still rare in the departments of the North: inter-service days, considered “precious” by the two partners, and various collaborations to prevent but also manage the outbreak of fires thanks to the in-depth knowledge of the terrain, both archaeological and biological, available to the ONF. To fight the enemy, the organization does not skimp on the means. The office develops the tracks that must be in order to facilitate the passage of trucks, installs fire risk awareness panels to alert walkers, and, above all, has buried new cisterns the size of a semi-trailer. trailer and with a capacity of 30,000 litres. In 2022, it spent 56,000 euros on these last two investments alone. The first cistern was installed in 2016 and since then the forest has had four more. “We missed this equipment. It is essential to organize a rotation system which saves time and to avoid the risk of emptying the water towers during an operation”, indicates the commander Tanguy Bannier in front of a huge map of the forest, at the entrance to the barracks.
Firefighters, too, are constantly increasing their resources. In the spring, the SDIS 77 acquired a new truck from the same range as those used in the Var with 6,000 liters of capacity, compared to the usual 4,000, and enhanced safety for the modest sum of 334,000 euros. A second is even already ordered and the commander hopes to procure others in the years to come. And if, until now, no aerial means have ever been necessary to put out a fire in this area where the population density is very high, the firefighters are preparing for it. The Canadairs have practiced scooping in the Seine and will soon practice above the forest. On the other hand, the use of drones is already well integrated into operational protocols. They make it possible to estimate the surface affected, to identify hikers on the spot and to evacuate them using an integrated loudspeaker. But it doesn’t stop there. During the operation, the remote pilots guide and direct the forces on site and, once the fire is almost extinguished, they identify the hot spots under the ground thanks to a thermal camera integrated into the drones before the firefighters drown them. Other avenues of reflection are in progress, such as the installation in the forest of surveillance cameras which could detect columns of smoke thanks to an algorithm and immediately notify the emergency services. Responsiveness is a compass for this barracks located about fifteen minutes from each sector of the forest… But beyond the equipment, it is also the entire training component that had to be reinforced. “A quarter of our workforce is trained in forest fires, i.e. 1,150 firefighters. It’s really atypical for a northern region”, notes Commander Bannier before adding that they “duplicate the training courses designed in the South” but also that the officers are sent there in “hardening”. An essential sharing of knowledge in the face of the fires which are inexorably climbing in latitudes hitherto spared.
Unless prevention gains ground. In 2014, the Var civil security center organized a search along a road near a mountain range: over 100 meters, nearly 2,240 cigarette butts were found on a single side. The opportunity to drastically strengthen information campaigns in the region. But in Ile-de-France, awareness of the danger remains more limited, judge the association of Friends of the forest of Fontainebleau. To improve it, it organizes once a semester dedicated walks to visit the burnt areas in the presence of an officer who piloted the extinguishing operation. The members of the association also go out to meet the public, explain the behaviors to avoid, for a year during the weekends of high attendance. An awareness that civil security would like to see spread everywhere from the start of the school year with the establishment of a day dedicated to security, in various fields, entitled “Japanese Day”, in reference to the very significant risk education in the country of Sunrise. Because adapting to danger means above all being able to identify it.