California wildfires are often made worse by the hot, dry Santa Ana winds , which can carry a spark for miles. Heat sources help spark the wildfire and bring fuel to temperatures hot enough to ignite.
Lightning, burning campfires or cigarettes, and even the sun can all provide sufficient heat to spark a wildfire. Violent infernos are most common in the western states, where heat, drought, and frequent thunderstorms create ripe conditions. Wildfires also occur around the world and in most of the 50 states. Firefighters battle blazes by depriving them of one or more of the fire triangle fundamentals.
One traditional method is to douse existing fires with water and spray fire retardants. Firefighters also sometimes work in teams, often called hotshots , to clear vegetation from the land around a fire to contain and eventually starve it of fuel. The resulting tracts of land are called firebreaks. Firefighters may also employ controlled burning, creating backfires , to stop a wildfire. This method involves fighting fire with fire. These prescribed—and controlled—fires remove undergrowth, brush, and litter from a forest, depriving an otherwise raging wildfire of fuel.
Although they can be dangerous to humans, naturally occurring wildfires play an integral role in nature. By burning dead or decaying matter, they can return otherwise trapped nutrients to the soil. They also act as a disinfectant, removing disease-ridden plants and harmful insects from an ecosystem. Wildfires thin forest canopies and undergrowth, allowing sunlight to reach the forest floor and a new generation of seedlings to grow.
In fact, some species of trees, like sequoias , rely on fire for their seeds to even open. Wildfires devastate anything in their path.
While they are difficult to stop, there are many steps people can take before, during, and after wildfires to limit their damage. All rights reserved. Climate Wildfires. How wildfires start Though they are classified by the Environmental Protection Agency as natural disasters , only 10 to 15 percent of wildfires occur on their own in nature. Share Tweet Email.
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The firefighting strategy for a forest or rangeland fire will differ from that for a fire near structures. Other factors are also important, such as the presence of people, pets, or livestock. This information is used to choose tactics and to allocate resources in order to save lives, homes, personal property, and valuable natural resources. Cutting a new fireline. Next, wildland firefighters usually focus on establishing a fire line.
A fire line is a break in fuels created by removing all vegetation up to an existing barrier. The barrier can be:. Fire lines are started at an anchor point, usually the coldest part of the fire.
The anchor point ensures a safe barrier between the fire and any unburned vegetation that could ignite and trap firefighters. The width of a fire line depends on topography, types of fuels, and weather—all factors that determine fire behavior. Fire lines often are constructed using hoe dads, shovels, or bulldozers. A prescribed burn is another method, also called a burn out. The IC then reports to the regional duty officer and orders resources applicable to the current and expected fire situation.
Management positions are added and taken away depending on the fire situation. Often, preparatory suppression tactics are used a distance away from the oncoming fire. This is called an indirect attack. Indirect attack can include the use of firelines, backburning and wetting unburned fuels.
It can also include the creation of control lines, which are boundaries that contain no combustible material. Control lines can be constructed by physically removing combustible material with tools and equipment, or portions may be naturally occurring. Lines may also be created by backfiring—that is, creating small, low-intensity fires using driptorches or flares. The resulting fires are extinguished by firefighters or, ideally, directed in such a way that they meet the main fire front, at which point both fires run out of flammable material and are thus extinguished.
Additionally, the use of long-term retardants may be used. Such compounds reduce the flammability of materials by either blocking the fire physically or by initiating a chemical reaction that stops the fire.
Unfortunately, any method can fail in the face of erratic or high-intensity winds and changing weather. Changing winds may cause fires to change direction and miss control lines.
High-intensity winds may cause jumping or spotting as burning embers are carried through the air over a fireline. Burning trees may fall and burning materials may roll across the line, effectively negating the barrier.
The IC determines an anchor point, generally located near the origin of the wildland fire or another point such as a road, stream, or trail where firefighters can begin to safely the fire. The IC designates an escape route and a safety zone where firefighters can go if fire conditions worsen, making it too dangerous to continue working.
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