Atmosphere And Weather

Atmospheric Effects of Wildfires

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"Atmospheric Effects of Wildfires"
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The earth rumbles, grumbles, snorts, and regurgitates- and no one can do anything about. Human beings, like all creatures on this planet, are at the whim of nature. Weather, volcano eruption, and earthquakes happen. These natural phenomenon cannot be controlled and are unpredictable. As human knowledge grows, man devises means to deal with natural events. Wildfires destroy beautiful landscapes, expensive homes and a variety of other natural and man made structures.

Wildfires are uncontrolled fires that burn grasslands and forests. In some countries, wildfires may strike peat deposits or bush lands. The cause of the fire can be natural due to lightning strike or man made such as arson or carelessness. Three factors are needed for wildfires to start and spread: dryness, low humidity and high winds. Once started wildfires race rapidly through grasslands, forests or bush land feeding on everything in its path.

Fire needs fuel and oxygen to burn. The fuel is provided by the grass, shrubs and trees that lie in the path of the wildfire. Oxygen is in the air. The Oxygen and fuel are quickly absorbed by the fire leaving carbon dioxide and debris. The particles and gases formed from the fire form smoke. The smoke is heavier than the surrounding air hangs low to the ground choking everything in its path. The heat from the blaze causes a hot air shaft to draw much of the smoke vertically. Winds associated with wildfires push the inferno horizontally. Soon the smoke plume is visible for miles. The particulate matter may travel long distances and may even be suspended in higher parts of the atmosphere causing sunlight to be blocked. The typical smoke smell may be perceptible for long distances. The life sustaining oxygen and the vegetative fuel needed to maintain the wildfire has been transformed into life choking gases and small pieces of burned matter.

The smoke plume filled with particulate matter spirals to the highest levels of the troposphere. The troposphere extends from the surface up to 8 miles. It is in this part of the atmosphere that weather develops. Beside the ability of a smoke plume to block sunlight, it may also cause the formation of a pyrocumulonimbus cloud. These types of cumulus clouds are associated with surface heat such is formed from volcanoes, industrial pollution and wildfires. The thunderstorm formed may in some cases extinguish the wildfire. In most cases, it carries the wildfire debris away from the fire zone.

When the resulting rain storm begins to discharge its rain, the wildfire debris drops to earth as well as the cloud's moisture. The rain mixture might drop as sludge-like precipitation. This sludge may coat cars, houses and streets. The particulate matter can cause health issues or death to the elderly, very young and those that suffer from respiratory aliments. Eye irritation and nausea are common occurrences in areas that are affected. In some cases, the debris can be carried for long distances before falling to the ground. The 1871 wildfire that destroyed Chicago produced hot cinders that were carried the 27 miles across Lake Michigan and caused fires to burn across the lake.

Wildfires use the atmosphere to transport particulate matter that may cause property damage and health issues downwind. The smoke plume carried into the upper levels of the troposphere blocks the sunlight and effects the weather. Besides the damage done in the immediate ground area of the wildfire, the fire debris affects the atmosphere. Like any natural phenomenon, prevention is limited. The conditions conducive to the Wildfire provide early detection warnings. The disaster associated with wildfires can be natural or, in many cases, man-made.

More about this author: Fran Moriarty

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