Wildfires, forest fires, bush fires, or grass fires —all of these simply refer to uncontrolled fires that wipe out large fields or land, only differing based on what kind of vegetation is being burned.
These fires can get out of hand quickly. They can last days, weeks, or even months. They can fully wipe out organic matter, wildlife, and structures within the vicinity.
How wildfires begin
Just like any other fire, wildfires need three ingredients to start. Firefighters refer to this as the combustion triangle:
- Fuel: It could be any sort of flammable material like trees, bushes, grasses, or structures. Australia, for instance, is filled with a lot of bushlands that can act as fuel to wildfires.
- Oxygen: Oxygen drives the combustion reaction that allows fire to burn. With strong winds, we can see why Australian firefighters are having trouble suppressing the bushfires.
- Heat sources: Another important factor for fire to successfully burn is a sufficiently hot temperature. Recently, Australia reached record-breaking temperatures which definitely worsened the fires in the continent.
How wildfires are stopped
Knowing the three necessary ingredients for fire to start, stopping wildfires then is clearly a matter of removing at least one of these three ingredients.
- Fuel: Wildfires can be deprived of their fuel source through back burning or controlled fires. The firefighters create fires that will burn up the fuel sources an on-going wildfire can use to strengthen its blaze. This method is literally fighting fire with fire.Firefighting crews called hotshots also are employed to control the area of the fire and remove vegetation which can serve as fuel to the wildfire.
- Oxygen: The use of fire retardants will take the place of the oxygen in a wildfire. This will inhibit the combustion reaction and effectively put an end to the fire. However, this method proves to be costly in fires that are of magnitudes seen in Australia.
- Heat sources: One way to eliminate heat is by using water, especially in the form of vapour or fog. The vapour absorbs heat which will lower temperatures. The manual use of water is not too practical since water is heavy and hard to transport in huge amounts.
Recently, there are reports of rain occurring in Australia which relieved the fires.
However, forecasters deem the amount of rain insufficient to bring an end to the wildfires. They fear that once the hot winds return, these fires might merge and form mega fires which may cause an even larger amount of damage.
Combinations and variations of these three methods are simultaneously employed to end wildfires. However, factors like erratic climate behaviour and global warming make them highly difficult to suppress.
Apart from these methods, the use of wildfire prediction tools can help avoid wildfires before they even start. Strengthening our efforts to curb the effects of climate change will also greatly help in preventing wildfires of just like what we are witnessing in Australia from happening again in the future.