Although wildfires have always been around, it is only over the last few years that there has been a significant rise in the severity of the fires and the sizes of areas burned. The key driver for these increases is climate change. In particular, the combination of wetter winters and hotter, drier summers creates the perfect conditions for wildfires.
Wetter, milder winters lead to increased growth of bushes and grass within forests and other habitats. This increased growth then dries out in the summer, and the lack of water, both in the environment and within the plants themselves, turns the added growth into the perfect fuel for a fire. The result is fires that are more severe and spread further and faster.
In 2023, 384 million hectares of land were burnt globally.
Wildfires are already beginning to appear in the UK as a result of climate change. Our wetter winters are fuelling growth that provides the ideal conditions for summer fires. And it’s not just forests that are at risk. Rare moorland habitats are very susceptible to wildfires too, which is why the National Trust has been trialling early detection methods on Marsden Moor in West Yorkshire.
Impacts of wildfires
Wildfires don’t just threaten human life and livelihoods; they destroy whole communities, consuming homes, hospitals, schools, and businesses – basically, anything in their path. They devastate wildlife habitats, killing the plants, animals, and insects that live there, leading to a drop in available biodiversity.
The fires also pose a life-threatening danger to the firefighters deployed to tackle the blazes. Attempting to control and extinguish wildfires costs billions. To give you an idea of the financial costs, a study by University College London found that California’s 2018 wildfires alone cost the US a whopping $148.5 billion.
Many wildfires start on the wildland-urban interface; in other words, they start in places close to human infrastructure and people. A good UK example of this is the 2022 wildfires in Dagenham and Wennington in East London. Fortunately, no lives were lost, but many homes, shops, vehicles, and acres of farmland were destroyed.
Detection
Wildfires can spread at a speed of up to 14.27 miles per hour, so it doesn’t take long for a tiny fire to become an uncontrollable monster. This is why early detection is so important.
The traditional forms of detection have been towers, cameras, and satellites. Towers are tall structures, usually in a forest, that have views over the canopy of trees. A human, or a camera, in the tower looks for plumes of smoke rising above the trees. Once spotted, firefighters can be called. However, by the time a fire is large enough for the smoke to have risen above the tree canopy, it is already well established and becoming difficult to tackle. Plus, it can be tricky to pinpoint the exact location of the fire and communicate that to the teams on the ground who may have many thousands of hectares to cover before they reach the source. All of this can delay the process of starting to put out the fire, which in turn allows the fire to spread further.
Satellites can also be used to detect wildfires, but they too come with some drawbacks. The fire has to be fairly large before a satellite will ‘see’ it, and unless the satellite is geosynchronous, it may not come into range until the fire is already out of control. However, satellites are a very useful tool for detecting the spread of fires and helping firefighters understand where the fire is going and how fast it is moving – all very useful intelligence when tackling a fire.
Until recently, these detection methods were the best available, but thanks to advances in technology, other options are becoming possible. For example, Dryad has developed sensors that can be placed in the forest (or other habitats) and can ‘smell’ tiny quantities of smoke, allowing even a small smouldering pile of leaves to be detected well before it turns into a giant fire. The sensors send an alert and can give an exact location, helping firefighters reach the spot as fast as possible. The sensors can even tell the difference between the fumes of a truck driving by and the smoke from a forest fire.
The internet of trees
Great as these advances in technology are, they are only practically useful if the data that the sensors and cameras, etc., are picking up can be relayed to a human who can then take the necessary action (for example, call out a fire crew).
Usually, data is sent via the Internet using mobile networks, but there is often scant mobile coverage in large forests or on remote hills covered with rare heathland. Yet, this is exactly where we need it if the early detection methods are to work efficiently. This is why Dryad has built Silvanet. Think of this as a mobile network for the trees: the Internet of Trees. With solar-powered Gateways placed at regular intervals, the sensors can speak to each other and send their data out of the forest to the people who need to receive it and take action. This doesn’t mean you can use your mobile deep within the forest, but it does mean the forest can ‘talk’ to the outside world and let it know if a fire is starting.
Prediction
Advances in technology are already making both detection and mitigation easier, faster, and more accurate. But imagine if you could predict where a fire will start. This is where artificial intelligence (AI) can help.
Although predicting the exact start location of a wildfire is challenging, calculating the risk can provide reasonable prediction accuracy.
Currently, fire risk is determined through a combination of weather information from satellites and, where available, enhanced with data from local weather stations. Fire risk is then calculated to be around 1 km². This is good, but not perfect.
More advanced calculations are based on VPD (vapour pressure deficit), which is the difference between the amount of moisture that’s in the air and the amount of moisture that air could hold at saturation. From a wildfire perspective, consistently elevated VPD (in other words, drier air, holding less moisture than saturation) means that ecosystems can more easily ignite and spread fire, leading to the larger, higher-severity wildfires.
Calculating fire risk levels by considering various sources of information (satellite, weather stations, and potentially local sensors) and then mapping the risk is a complex and tedious task. But it can be automated and enhanced in accuracy and resolution with the help of AI. Adding more fine-grained information, such as soil and air moisture levels measured by sensors embedded in the forest, would help to take into account the microclimate of the forest. In the future, we may even be able to measure the fuel moisture (grass, leaves, and needles), rather than just the soil moisture. This would make risk calculation, and therefore fire prediction, even more accurate.
Firefighting technology
Once a fire is detected, it needs to be extinguished. This usually means firefighters and trucks on the ground, and perhaps helicopters or planes dropping huge quantities of water on the fire from above.
If a fire can be detected sooner, then the number of people and the amount of equipment needed can be reduced considerably. Something the size of a bonfire is easily contained by a single team and one truck, but once you have acres of trees aflame, it can require hundreds of people and dozens of fire trucks, plus aerial support.
This can be compounded by accessibility. Even when a fire is spotted in the very early stages, it can take time for the fire crews to reach it. It could be in a remote location or in a landscape that is difficult to traverse – perhaps vehicles can’t reach the spot.
Drones could provide the solution. Imagine if the sensor could detect and pinpoint the fire and then send an autonomous drone to the very spot it is needed to extinguish the fire. Fires could be caught quickly, safely, and (relatively) cheaply. Dryad has recently received €3.8 million in EU grant funding to develop drones with this capability and hopes to have the first working units available in the next 2–3 years. This could mark a genuine game changer in the fight against the destruction of wildfires.
The future
Currently, governments around the world are focusing (and spending millions) on increasing the number of firefighters, trucks, and planes available to tackle the fires. In the coming years, I expect to see a gradual movement away from this type of spending, and instead we’ll see investment in detection and mitigation technology. The use of improved prediction modelling enhanced by a variety of environmental sensors, including those for early detection, combined with automated firefighting methods like autonomous drones, could see us begin to win the war against the destruction caused by severe wildfires. It requires the political will and financial commitment of governments, but with the costs of wildfires only set to increase, the pressure will be on to cut costs without jeopardising lives and further damaging the environment.
Carsten Brinkschulte is the CEO and co-founder of Dryad Networks. Dryad provides ultra-early detection of wildfires as well as health and growth monitoring of forests using solar-powered gas sensors in a large-scale IoT sensor network.