Wildfire. An outdoor fire burning of varying intensity that is determined by it s surrounding

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1 Donyel Blake 9/14/2003 Wildfire An outdoor fire burning of varying intensity that is determined by it s surrounding environment. Wildfires are created numerous ways. They can be created through a spark, the sun s heat, or a lightning strike. Most wildfires are created by human activity such as arson; neglected campfires, improper burning and discarding lit cigarettes. Certain conditions are needed for wildfires to occur. Drought conditions are needed to favor the ignition of a wildfire. The three main factors needed for wildfires to occur are air to supply oxygen, a heat source, and a fuel source. Everything has a flash point, which is a temperature that an object will burst into flames. The flash point of wood is 572 degrees Fahrenheit. An average of 5 million acres burn each year in the United States and cause millions of dollars in damage. Once ignited wildfires can spread very rapidly up to a rate of miles per hour. They are usually fueled by dry vegetation, dry grassy fields, and underbrush, trees, and even homes. Fuel, weather, and topography determine how a wildfire will spread. These three factors can determine if a wildfire will quickly spread or burn out. The amount of fuel a wildfire can burn on is called the fuel load. The fuel load is measured in tons per acre. Small fuel loads cause a fire to burn and spread slowly at a low intensity. A wildfire with a high fuel load will spread rapidly and burn more intensely. After a fire begins to spread it creates a more easy to burn environment around itself.

2 As it spreads the heat from the fire dries out moisture from the surrounding environment. This makes the material around it much easier to burn once the fire reaches that area. Wildfires also create winds that can be up to 10 times stronger than the winds surrounding it. Wind also has the ability to supply a fire with additional oxygen, which can allow the fire to spread at a more rapid rate. The winds in a wildfire can also ignite other fires in an area by blowing embers and ash up into the air and landing in another area. In humid conditions it is difficult for wildfires to spread. When air becomes saturated precipitation raises the moisture level and prevents further wildfires from igniting. Topography is also an influencing factor in the spread of wildfires. Fire travels more quickly uphill than downhill. The steeper a hill slope is the faster a fire will spread, due to the surrounding winds which usually flow uphill. Once wildfires reach the top of a hill they usually burn out. There are three types of wildfires that can occur. They are classified as surface fires, ground fires, and crown fires. A surface fire is a fire that burns in grasses and low shrubs. It can get as high as 4ft tall and reach the lower branches of trees. Surface fires are the most commonly found type of wildfire and they can spread very rapidly. Ground fires burn along or just below the ground surface. They are usually sparked by a lightning strike. Ground fires can burn in duff, roots, and organic soils. Crown fires burn in the tops of trees. They are fueled by winds and are hard to contain once they have begun.

3 After a wildfire has burned out it can often cause other problems in its wake. When fires burn they engulf all of the vegetation and weaken soil and it s organic contents near hillsides and mountainous locations. This prevents water from penetrating through the soil, which can lead to dangerous soil erosion and debris flows. Wildfires are becoming a more serious threat to humans and their houses. More people are building their homes into forested areas that are prone to wildfires. These people are not taking protective measures against wildfires. Wildfires can also affect water supplies. After being burned, land surfaces are susceptible to erosion, which flow into watershed systems. These watershed systems feed into reservoirs, which supply water to towns and cities. While many wildfires are destructive a few are also beneficial. Wildfires reduce disease spread by benefiting plant growth by releasing nutrients from burned plants into the ground that encourages new growth. Some wildfires also burn the underbrush of a forest, which prevents a larger fire from burning, that would result if the brush were allowed to accumulate for a long timeperiod. Wildfire management is critical in battling wildfires. NOAA officials have played key roles in the battling of wildfires across the United States since NOAA National Weather Service meteorologists send out site-specific forecasting for wildfires of all sizes from half an acre to many thousand acres. ( Affairs pg1 Ln 2-3). NOAA uses their satellites to provide views of current burning U.S. wildfires. Firefighters depend on accurate forecasts of wind direction and speeds. This allows them to make the best possible decisions to get a wildfire under control.

4 The accuracy of the forecast also helps ensure the safety of the individuals involved in the containment of wildfires. Hot shots follow the spreading of wildfires. Hot shots are firefighters that work in 20-person groups that try to stop a spreading wildfire by building a break around the fire, to stop it from spreading. The National Weather Service (NWS) also plays a major role in predicting wildfire conditions before they start. Forecasters look at areas where dry weather conditions may occur throughout the U.S. They monitor areas that contain hot temperatures, low humidity levels, and high winds. They also look at where dry thunderstorms may occur to help officials plan ahead as to where a fire may develop. This monitoring of dry conditions helps smokejumpers determine where to go and aid in small-scattered fires. Smokejumpers are firefighters that jump out of planes to control small blazes in remote areas. They try to control small fires and keep them from spreading into larger ones. There are only a few hundred smokejumpers in the U.S. They are all employed by the Bureau of Land Management or the U.S. Forest Service. Firefighters also use another method of fighting wildfires by creating backfires. These backfires are started by ground crew firefighters. They start the backfire in order to burn any fuel that the progressing wildfire may feed on when it reaches that point. The National weather service also has experienced meteorologists called Incident Meteorologist. Each year several of these highly skilled meteorologists go out to locations where firefighters are working. Here they help with and are part of the safety and tactical support for the fire team. The meteorologists provide on site forecasting, the behavior of fire, and fire operations. They use lab top computers to access information from local National Weather Service offices.

5 The meteorologists also access NOAA s satellites and use them to rapidly detect and monitor forest fires. This information is especially helpful in secluded locations where smoke can t be located on radar or visibly seen because there are no people in that area. People living in certain locations are at risk for wildfires. These locations are people who make their homes in woodland locations, rural areas, forests, and remote mountain sites. There are several ways for people living in these locations to practice wildfire safety. One way is to contact a local fire department, health department or forestry office for information on fire laws. You should make sure your home is easily accessible by emergency vehicles. Make sure your address is displayed in driveway entrances. Report hazardous conditions that could cause a wildfire. Children should be taught about fire safety and keep matches out of their reach. Post fire emergency numbers, plan escape routes, and talk with your neighbors about wildfire safety and create neighborhood networks. There are precautions you can also take around your home in case it is threatened by wildfire. You should try to design your home s landscape with materials that can help contain and not fuel a fire within a zone of feet around your home. Homes situated in pine forests should have a safety zone of 100 feet. You should regularly clean your roof and gutters. If your home has a chimney make sure to clean it at least once a year. Rake fallen leaves often and clear all flammable vegetation. Remove any dead branches that extend over the roof of your house. If you are not able to do this contact your local power company to do so.

6 Mow your lawn regularly. Store gasoline, oily rags and other flammable materials in approved safety cans, and keep cans in a safe location away from the base of buildings. Identify and maintain an adequate source of water outside such as a swimming pool, or pond. Install a smoke detector on each level of your home near bedrooms, test them monthly and change the batteries at least two times a year. Make sure to have a ladder handy that will reach the roof of your house. Have a garden hose that is long enough to reach any area of the home and other structures on the property. If your home is threatened by wildfire there are some instructions to follow. If you have a garage connected to your house back your car into your garage. Disconnect garage windows and doors. Close car doors and roll up windows. If you do not have a garage keep your car near the back or front door of your house for easy access. Arrange temporary housing at a friend or relative s house outside of the alerted area. If you are advised to evacuate, tell someone when you are leaving and where you are going. You should wear protective clothing long pants cotton or wool clothing long sleeve shirt and gloves and a handkerchief to protect your face. In your home before a wildfire threatens you should have a disaster supply kit with items you may need, if advised to evacuate. This kit should contain a three-day supply of water, one gallon per person per day and food that won t spoil. One change of clothing, and footwear per person, and one blanket or sleeping bag per person. A first aid kit that should includes your families. You should also have sanitation supplies included in your kit. Wildfires can occur in any area at any time. Most U.S. western wildfires are seasonal. They occur between the Months of May and October.

7 This period follows the mid latitude cycle which favors a low amount of precipitation, and high temperatures over the western states. Their frequency can be predicted in areas prone to wildfires going through unusually low precipitation or drought. Regions most vulnerable to wildfires are areas with lots of trees, and grassy areas with brush. States in the U.S. that are at biggest risk for wildfire outbreaks are Kansas, Mississippi, Louisiana, Georgia, Florida, North Carolina, South Carolina, California, Massachusetts, and the National forests in the western U.S.

8 Works Cited Wildfire News. Accessed 9/12/03 USGS. Science for a changing world Accessed9/9/03 Types Of Wildfires Accessed 9/15/03 Where do Wildfires Occur? T3.preservice.org/T /wfgeolocation.htm Accessed 9/15/03 Howstuffworks How Wildfires Work Science.howstuffworks.com/wildfire5htm. Accessed 9/9/03

9 Noaa s Support to Wildfire Management