Understanding how wildfire spreads is the key thing to controlling and managing it. Knowing the various factors affecting a wildfire will help determine how fast it spreads and how difficult it will be to control it. Weather is one of the top factors affecting a wildfire. It comprises wind, temperature, and humidity. When the temperature is high, vegetation dries, and as a result, wildfires spread fast. Ground temperature also affects how air currents move.
When we have strong winds, wildfire will spread faster. It additionally brings more air to the fire. Flattening the flame also causes fuel to pre-heat, causing fire sparks which start more fire ahead. During the day, the wind blows upslope at a rate of 5-10 miles per hour. It, however, flows downslope at night because the air is cooler, making it sink. It is therefore important to understand the direction of the wind when attacking a wildfire.
Topography determines the rate and direction in which the wind flows. Factors affecting topography include slope, terrain, and aspect. A wildfire will move fast, both uphill and downhill. Fire will spread fastest on the steepest slope because fuels are dry and ignite faster compared to a leveled ground, flames are closer to fuel on the uphill, burned fuel may roll down, increasing the spread of the fire. (Jazebi 263.) On the other hand, the aspect will help you understand where fuels are driest and less dense, the direction that receives more sun and hence drier, and places where there is a likelihood of stronger winds.
Wildfire Fuels
A wildfire investigative process must be carried out using a systematic approach. Knowing and understanding the different types of wildfire fuels is therefore very key. The investigative process includes determining the origin of the fires, cause, direction, and the events that led to the spread of the fires.
Wildfire fuels are categorized into two groups, fast-burning fuels and slow-burning fuels. Fast burning fuels include dry grass, small trees, and dead leaves, which burn out very fast and kindle heavy fuels. (Belcher 240) However, not all dead leaves and light fuels increase the spread of a fire. Some, such as low brushes, stop the spread since they have moisture that keeps the leaves wet and stops or suppresses the ignition. On the other hand, fast-burning fuels include logs, topsoil, and branch woods. They ignite and spread slowly, throwing huge volumes of heat.
Understanding wildfire fuels will also help understand their spacing which is key in determining how the fire will spread and in what direction. This knowledge is also important in suppressing the fire by breaking its continuity. Aerial fuels such as tree branches, snags, and high brushes are affected by dead branches, snags, and tree needles. Aerial fuels and ground fuels are linked by small trees and mid-sized brushes, which easily catch fire due to their proximity to ground fuels spreading it to aerial fuels. (Belcher 230) Understanding the different types of wildfire fuels and their role in spreading fire is key in investigating the wildfire process.
Recommendations for Land Management and Wildfire Prevention
Fire ecological benefits outweigh the disadvantages. Constant fires help in reducing the chances of a huge potential wildfire. Fire also helps eliminate foreign plants that compete with native plants for nutrition and space. It also helps sunlight reach the forest floor, which is important for the growth of native plants. After the fire, the ash remains to act as nutrients for the other plants. (Baltzer 119)The burned trees act as the home for nests and some animals. When they decay, they become nutrients for those that survived. The fire also kills insects that harm the trees and gives a chance for new grass and shrubs to germinate. Therefore, fires play an important role in biodiversity maintenance and nutrients cycling resulting in a healthy ecosystem.
Landscape managers can reduce the risk of ignition, frequency, and impact of an unplanned wildfire by controlling high flammable plants and developing procedures that will curb the increased spread. Additionally, considering climate changes and variability when creating wildfire and land management strategies is essential, as well as implementing long-term monitoring programs for wildfire fuels and biodiversity. Landscape managers should also hold conferences to teach the public how to manage public land and handle fire in an environment that is changing. (Martin and Wade). For instance, to effectively manage all emergency wildfires in Canada, the government has created an all-hazard approach, Public Safety Canada, which issues national coordination to all federal agencies for emergency management on Canada’s federal lands.
Suppression Strategies
The effects of various suppression strategies on wildfire may outweigh the effect the fire itself might have caused. A current transfer from fire control to fire management has led to an increase in attention to reducing the effects of suppression on the investigative process. Suppressing wildfires affects land through erosion which affects the area’s topography, disrupting the investigation results. (Baltzer128) It also leads to chemical contamination, sedimentation, and ambiguity.
The creation of back burns increases soil and water contamination and disrupts the natural fire making the investigative process difficult. It also increases the total area burned down and fostered more acute fires. (Martin and Wade). During suppressing fire, there will have to be the creation of roads to follow and fields where airplanes can land, which tampers with the landscape and ecology of the area, which are major factors in the investigation process. As a result, natural ways of suppressing such as clearing, creating natural barriers, and fire lines are highly recommended since they do not tamper with the natural fires.
As much as we encourage fire suppression to reduce the impact and spread of wildfires, we must note that some of these suppression strategies may significantly impact the fire itself. They may also disrupt the investigative process resulting in inaccurate data and results on questions such as the causes of the fire, direction, and the effect the fire might have on the ecology of that particular forest. As a result, the use of natural methods to suppress, which will leave no trace of tampering, is highly recommended.
Work Cited
Baltzer, Rochelle. Wildfires. ABDO Pub. Co., 2012.
Belcher, C. M. “Impacts and Wildfires – An Analysis of the K-T Event.” Impact Studies, pp. 221-243.
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Jazebi, Saeed et al. “Review Of Wildfire Management Techniques—Part I: Causes, Prevention, Detection, Suppression, And Data Analytics”. IEEE Transactions On Power Delivery, vol 35, no. 1, 2020, pp. 430-439. Institute Of Electrical And Electronics Engineers (IEEE), doi:10.1109/tpwrd.2019.2930055.
Martin, Wade E., et al. Wildfire Risk: Human Perceptions and Management Implications. Routledge, 2010.
Nader, Glenn, et al. “Planned Herbivory in the Management of Wildfire Fuels.” Rangelands, vol. 29, no. 5, 2007.
Riley, Karin, et al. “A Model-Based Framework to Evaluate Alternative Wildfire Suppression Strategies.” Resources, vol. 7, no. 1, 2018, p. 4.
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