Deadly Wildfires Can Be Avoided By Detecting Them Soon Enough. Hello everyone, I hope you are well. In today’s post, I will be sharing a guest post from Carsten Brinkschulte, CEO and Co-Founder of Dryad Network. Carsten will explore the future of wildfire detection approaches and how to protect our forests. Wildfires can spread shockingly fast (up to 23km/h / 14mph), consuming everything in their path. As global temperatures rise, so does the risk of wildfires. They cause around 20% of global CO2 emissions and eliminate the habitat for two-thirds of all biodiversity on Earth, and they can cost a country’s economy billions. So, early detection is essential.
Deadly Wildfires Can Be Avoided By Detecting Them Soon Enough
You cannot outrun a forest fire. Wildfires can spread shockingly fast ─ up to 23km/h (14mph) under the right conditions ─ consuming everything in their path. They are often highly destructive when they take hold, highlighting the vital need for early wildfire detection.
As global temperatures rise, so does the risk of wildfires. Periods of hot, dry weather can turn a forest’s undergrowth into perfect kindling. Any hot spark can set dry undergrowth aflame.
The majority of wildfires, approximately 85%, result from human activity, such as carelessly discarding cigarettes, neglecting to extinguish campfires, accidents, and arson.
Wildfires are a vast and growing problem. They cause around 20% of global CO2 emissions, almost the same as all traffic worldwide. Burning forests decimates the world’s most significant carbon capture and storage system and eliminates the habitat for two-thirds of all biodiversity on Earth.
In addition to their environmental impact, wildfires also cause substantial economic damage. As recently reported to the United States Congress, climate change-fuelled wildfires cost the US economy between $394 billion and $893 billion annually. The state of California alone spends around $1.5bn a year on fighting wildfires.
By detecting wildfires while still small, we stand a much better chance of stopping them before they cause too much damage, saving money, the environment and, ultimately, lives.
Classic Wildfire Detection: Watchtowers
If you haven’t seen a watchtower in and around a forest, you will likely have watched a movie or TV show where one has been featured. Watchtowers have been vital watchtowers for some time as a way to spot fires. Recently, Artificial Intelligence (AI) enhanced cameras have been mounted on watchtowers, adding a sci-fi spin to this classic fire detection method.
Multiple watchtowers make it possible to triangulate and send firefighters to the exact location of a fire. Fire watchers can then use the towers to keep track of the size and location of the fire as it progresses.
Watchtowers—manned by humans, cameras or AI—can overlook a large area, with a single watchtower having an observable radius of up to 18km.
However, watchtowers have limitations. Smoke has to rise above the tree canopy to become visible from a watchtower, and tree canopies hold down smoke. It is almost impossible to detect a small fire underneath a tree canopy, where most wildfires start. When they are large enough to be seen, they will have been burning for hours and may be too large to extinguish when the firefighters arrive at the scene.
The other main issue with watchtowers is visibility. Haze, fog or dust from crop harvesting can obscure visibility or cause false positives, and obstacles such as hills can block the view.
Space-Age Wildfire Detection: Satellites
Satellites offer a different view of potential trouble spots. Satellites can have geostationary orbits (a fixed location relative to Earth) or Low Earth Orbits (LEO), where satellites move relative to the Earth. Both employ camera technology but are used differently: Geostationary satellites keep watch over one forest area; LEO satellites work as part of a network to provide global coverage.
With their wide field of view, satellites are excellent at tracking wildfires, but distance is an issue.
Geostationary satellites orbit the Earth at distances around 36,000km. This far from the ground, a single pixel is the equivalent of 500x500m. Fires need to be pretty substantial before geostationary satellites can detect them.
While LEO satellites are closer to the surface (about 600km above us) and can provide better resolution because they constantly move relative to the Earth’s surface, they only pass each area once every six hours. In six hours, a fire could have shifted from smoking to unstoppable. Hundreds of LEO satellites can reduce the revisit time to less than 30 minutes, but even then, the resolution on offer is around 100x100m – roughly the size of two football pitches.
Sadly, satellites are not ideal when it comes to the early detection of wildfires. They are superb tools for monitoring wildfires and can help predict where and how fires will develop.
New Technology: Gas Sensors
Gas sensors are positioned in forests below the tree canopy and use AI to detect smoke from fires accurately – they can tell this from things such as fumes from vehicles. As gas sensors are typically solar-powered, they can be positioned anywhere and run for more than ten years without needing an external power supply or battery swap.
A considerable advantage offered by gas sensors is their ability to detect wildfires as early as the smouldering stage, where they can be extinguished much more efficiently and effectively before they spread and become extremely dangerous.
Therefore, Gas sensors are best suited to cover high-risk, high-value areas in the wildland-urban interface (WUI) – places where people hike, camp or drive, power lines and railroad tracks, and anywhere else where fires have proven more common.
However, gas sensors have a limited range; one sensor is needed for every five hectares of woodland (more in high-risk areas). It’s a lot less than a satellite. But they also cost much less than a satellite – less than $100 per sensor, so the overall protection cost is still very competitive compared to other approaches.
Combining Detection Methods
There are advantages but also limitations to every wildfire detection approach. No silver bullet will solve the growing wildfire crisis on its own. Watchtowers, cameras and satellites often require the fire to reach a specific size and intensity before it can be detected. Sensor-based approaches are practical in the WUI but impractical to cover the entire forest.
However, combining multiple solutions makes it possible to create an optimal system. The advantages of one approach can be used to cancel out the disadvantages of another.
Since most wildfires are caused by human activity, it makes sense to focus gas sensors on WUI areas ─ the areas of forest that come into most contact with people ─ which are the highest risk. Since these areas are relatively small, gas sensors can effectively cover them for ultra-early detection at a low cost. Despite being relatively small in area, they are increasing by around two million acres a year, and they are the very area where wildfires can wreak the most damage, owing to their proximity to humans and human infrastructure. This makes ultra-early detection especially important in areas where sensor-based approaches are far superior.
Natural Causes Of Wildfire
Outside human activity, the only natural causes of wildfires are lightning, lava, and (very occasionally) meteors. Lava is uncommon and relatively easy to predict, yet almost impossible to stop. Lightning is less predictable yet highly visible, making it easy to spot with cameras mounted on watchtowers. Wildfires caused by meteors are infrequent but tend to be very visible, so they are often easier to spot and tackle.
If a wildfire does develop outside of the high-risk areas or out of view of the cameras, it can then be detected and tracked using satellites, helping to reduce the damage and loss of life.
By combining all three approaches, we could effectively manage the majority of wildfires before they become too large and unmanageable. Not only would this save forests but also homes, livelihoods and lives, both public and firefighters tackling the blaze.
In the future, we may even be able to combine these detection methods with automated extinguishing machines – drones carrying small payloads of water or other extinguishing methods to the location of a small fire. These drones won’t be able to tackle large fires, so early detection is crucial for their efficacy. Yet, with a fleet of automated drones directed by accurate ultra-early detection systems, we could all but eliminate destructive wildfires for good.
With wildfires becoming more common, intense and deadly, investing in wildfire detection is more important than ever. Finding the perfect mix of approaches will be a far better solution than picking a favourite, and it could help enable the future development of automated firefighting systems.
I hope you enjoyed that.
About The Author
Carsten Brinkschulte is CEO and co-founder of Dryad Networks. Dryad provides ultra-early detection of wildfires and health and growth monitoring of forests using solar-powered gas sensors in a large-scale IoT sensor network. Dryad aims to reduce unwanted wildfires, which cause up to 20% of global CO2 emissions and devastate biodiversity. By 2030, Dryad aims to prevent 3.9m hectares of forest from burning, preventing 1.7bn tonnes of CO2 emissions.