From a distance, the flames of a forest fire may seem straightforward, but in reality, wildfires come in different forms. Some are less dangerous and can be controlled with relatively simple methods, but crown fires are not in this category.
Every firefighter knows that the outbreak of a crown fire marks the beginning of dangerous days and a direct confrontation with life-threatening conditions.
To better understand this phenomenon, it is important to know that wildfires occur at three levels:
- Surface fires: These burn only the forest floor and the dry vegetation on it. Preventing and controlling this type of wildfire is easier, and simply removing dry fuel from the ground can significantly reduce the risk.
- Ground fires: In this type, the fire burns beneath the surface, in tree roots and underground layers of soil. Due to its hidden and extensive nature, it is more challenging to detect and control.
- Crown fires: The most dangerous form of wildfire, starting at the forest floor, climbing up the tree trunks, and eventually reaching the canopy. Coniferous trees are especially vulnerable because their connected crowns allow flames to spread quickly.
Research has shown that crown fires can spread up to ten times faster than surface fires. With such speed, the damage is inevitably severe, and even the mention of the term can send shivers down the spines of firefighters and local residents.
Why Are Crown Fires More Dangerous?
We mentioned that the primary reason crown fires are so dangerous is their rapid spread, but let’s dive a little deeper:
- Difficult Access to the Fire: Most firefighting equipment is designed for surface fires. Therefore, reaching and controlling crown fires is much harder. The flames can reach very high, making extinguishing efforts extremely challenging.
- Rapid Spread: Trees exposed to crown fires provide ample dry fuel, which significantly increases the speed at which these fires spread.
- Creating New Fire Spots: Crown fires produce sparks that can be carried by the wind to distant locations, igniting new fires far from the original blaze.
Given these factors, it’s easy to understand why crown fires cause so much alarm.
What Causes Crown Fires?
Several factors contribute to the development of crown fires, with the most important being:
- Strong Winds: Winds lift the flames higher and accelerate the fire’s spread.
- Accumulation of Natural Fuel: Dry branches and needle leaves piled up on the forest floor increase the risk of crown fires.
- Severe Dryness and Low Humidity: Hot, dry summer days dry out tree foliage, making it more flammable.
- Flame Height: When flames grow tall enough to easily engulf the lower branches of trees, the risk of crown fire increases.
How Can We Prevent Crown Fires?
When examining strategies to manage and prevent crown fires, the solutions may seem straightforward:
- Vegetation Management: Remove dry branches, thin tree density, and prune lower branches.
- Controlled Burning: In cooler, low-risk seasons, intentionally burn excess fuel in a controlled manner.
- Firebreaks: Clear land near trees to prevent flames from spreading to the canopy.
- Modern Detection Technologies: Use drones, satellites, and early warning systems to detect fires quickly and send alerts.
Final Thoughts
At SenseNet, we have implemented various measures to prevent crown fires. Our system employs artificial intelligence, cameras, and sensors to detect danger within less than 10 seconds and alert local authorities immediately.
Crown fires remain one of the most complex and dangerous challenges in natural resource management. However, with technological advancements, we can confront and control this critical threat more effectively.