Wildfires

 Wildfires

What Is A Wildfire

Wildfires are any unplanned fires that burn in forests and other wildlands, such as shrub or grass communities. They’re a powerful natural force we must fully understand and respect in order to best help control them. Nearly nine out of ten wildfires nationwide are caused by humans and could have been prevented.

How Wildfires Start

On a hot summer day, when drought conditions peak, something as small as a spark from a train car's wheel striking the track can ignite a raging wildfire. Sometimes, fires occur naturally, ignited by heat from the sun or a lightning strike. However, the majority of wildfires are the result of human carelessness.

­Everything has a temperature at which it will burst into flames. This temperature is called a material's flashpoint. Wood's flashpoint is 572 degrees Fahre­nheit (300 C). When wood is heated to this temperature, it releases hydrocarbon gases that mix with oxygen in the air, combust and create fire.

There are three components needed for ignition and combustion to occur. A fire requires fuel ­to burn, air to supply oxygen, and a heat source to bring the fuel up to ignition temperature. Heat, oxygen, and fuel form the fire triangle. Fire­fighters often talk about the fire triangle when they are trying to put out ablaze. The idea is that if they can take away any one of the pillars of the triangle, they can control and ultimately extinguish the fire.

­After combustion occurs and a fire begins to burn, there are several factors that determine how the fire spreads. These three factors include fuel, weather, and topography. Depending on these factors, a fire can quickly fizzle or turn into a raging blaze that scorches thousands of acres.

Fuel Loads

Wi­ldfires spread based on the type and quantity of fuel that surrounds it. Fuel can include everything from trees, underbrush, and dry grassy fields to homes. The amount of flammable material that surrounds a fire is referred to as the fuel load. Fuel load is measured by the amount of available fuel per unit area, usually tons per acre.

A small fuel load will cause a fire to burn and spread slowly, with low intensity. If there is a lot of fuel, the fire will burn more intensely, causing it to spread faster. The faster it heats the material around it, the faster those materials can ignite. The dryness of the fuel can also affect the behavior of the fire. When the fuel is very dry, it is consumed much faster and creates a fire that is much more difficult to contain.

Weathers Role In wildfires

Weather plays a major role in the birth, growth, and death of a wildfire. Drought leads to extremely favorable conditions for wildfires, and winds aid a wildfire's progress weather can spur the fire to move faster and engulf more land. It can also make the job of fighting the fire even more difficult. There are three weather ingredients that can affect wildfires: Temperature, moisture, and wind.

As mentioned before, temperature affects the sparking of wildfires, because heat is one of the three pillars of the fire triangle. The sticks, trees, and underbrush on the ground receive radiant heat from the sun, which heats and dries potential fuels. Warmer temperatures allow for fuels to ignite and burn faster, adding to the rate at which a wildfire spreads. For this reason, wildfires tend to rage in the afternoon, when temperatures are at their hottest.

Wind probably has the biggest impact on a wildfire's behavior. It also the most unpredictable factor. Winds supply the fire with additional oxygen, further dry potential fuel, and push the fire across the land at a faster rate.

While wind can help the fire to spread, moisture works against the fire. Moisture, in the form of humidity and precipitation, can slow the fire down and reduce its intensity. Potential fuels can be hard to ignite if they have high levels of moisture because the moisture absorbs the fire's heat. When the humidity is low, meaning that there is a low amount of water vapor in the air, wildfires are more likely to start. The higher the humidity, the less likely the fuel is to dry and ignite.

Since moisture can lower the chances of a wildfire igniting, precipitation has a direct impact on fire prevention. When the air becomes saturated with moisture, it releases moisture in the form of rain. Rain and other precipitation raise the amount of moisture in fuels, which suppresses any potential wildfires from breaking out.

Fires On The Mountain

The third big influence on wildfire behavior is the lay of the land or topography. Although it remains virtually unchanged, unlike fuel and weather, topography can either aid or hinder wildfire progression. The most important factor in topography as it relates to wildfire is the slope.

Unlike humans, fires usually travel uphill much faster than downhill. The steeper the slope, the faster the fire travels. Fires travel in the direction of the ambient wind, which usually flows uphill. Additionally, the fire is able to preheat the fuel further up the hill because the smoke and heat are rising in that direction. Conversely, once the fire has reached the top of a hill, it must struggle to come back down because it is not able to preheat the downhill fuel as well as the uphill.

In conclusion, I hope we can all work together in lighting fires in a safe way, as if we don’t there will be millions of dollars every year in damage, which could be going towards schooling or cancer or something important, rather than just using it to repair from mistakes.