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The Anatomy of a Wildfire

Wildfires are defines as a raging and fast-spreading fire, creating risk for people who own homes, enjoy camping and travelling in wilderness settings, such as the wooded areas or grasslands.

Since many outdoor enthusiasts live or camp in these areas, you may be at risk. Making yourself aware Knowing the characteristics and causes of wildfires will ensure that you survive a wildfire disaster.

Wildfires have become a potential, natural hazard in many areas of the United States. This is very true of areas in which natural ecosystems become in contact with human development. Negative wildfire impact on naturally forested and grassy areas include: soil erosion, landslides and mudslides, and the supplanting of native plant growth with alien and invasive vegetation.

The United States Geological Survey, or USGS, along with the United States Forest Service, has a major role in providing the needed information by identifying risks and reducing the hazards of wildfires. By supporting the firefighting effort in a real-time basis, and also making assessments of a wildfire's devastation, the ultimate goal is build ecosystems and better prepared communities.

Natural Fire: Fire is a beneficial process in the natural world. In a sense, it "cleans house" by burning off built up organic matter than can be a source of fuel for a wildfire. Historically, natural fire suppression has led to many severe fires since vegetation build-up has created even more fuel for wildfires.

Three ingredients required for a fire to occur:

  • Oxygen
  • Heat
  • Fuel

Heat: There must be a source of heat to ignite a fire. Heat is necessary for the maintenance of the established fire, and permitting it to spread. Heat will remove the moisture from other nearby fuel sources, warm air in the immediate vicinity, and also heat up all fuel in its path. This will enable the fire to move on easily.

Fuel: Anything that can burst into flame serves as fuel for a fire. Its usefulness in sustaining fire is determined by how much moisture it contains. The size, shape, quantity, and disbursement of the fuel in a given area is also important.

Oxygen: Air used in combustion is made up of 21% oxygen content. Fires need approximately 16% oxygen to maintain a good burn. The fire's need for oxygen is to maintain the chemical process of oxidation that takes place in a wilderness fire. Burning fuel reacts with the oxygen in the air, and releases heat and production of other heat releasing products, such as embers.

Fact: 90% of wildfires that occur are due to the actions of human beings.

For more information on wildfires and survival during fire disaster:

http://pubs.usgs.gov/fs/2006/3015/2006-3015.pdf