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Forest fires - a curse or a blessing?

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The regions in the world most at risk of forest fires include Southeast Asia, Australia, California and the Mediterranean countries.
The regions in the world most at risk from forest fires include Southeast Asia, Australia, California and the Mediterranean countries.

Forest fires are unpredictable natural events that occur under natural circumstances primarily through lightning strikes. A lightning strike combined with long periods of drought and drought can have devastating consequences. Most forest fires are now caused by humans. The negligent handling of campfires and carelessly thrown away cigarettes or matches have already caused a large number of serious fires.

Slash and burn in the tropical rainforests of Africa, South America and Southeast Asia is just as dangerous. Parts of the "green lung" are burned to make way for arable land and plantations quickly and inexpensively. If the fire gets out of hand, large areas of the irreplaceable rainforest can quickly catch fire and are lost forever. Above all, droughts, which are exacerbated by the El Niño phenomenon, favor uncontrolled burning.

Targeted arson and pure vandalism are also increasingly to blame for fire disasters around the world. Experts assume that only 15 percent of all forest fires can be traced back to natural ignition caused by lightning.

The regions in the world most at risk of forest fires include Southeast Asia, Australia, California and the Mediterranean countries. There is a blaze of fire here almost every year. The catastrophic effects do not only relate to flora and fauna, but of course also to the people who live there.

Once a fire has started, there may be additional factors that make the fire rollers more likely. Probably the most important and dangerous natural element is the wind. He supplies the fire with additional oxygen and drives the flames in front of him. Local winds, such as the foehn, can also further accelerate the spread of a forest fire. The resulting eddies and turbulence tear the embers into the air or heat the fire like with a bellows. In addition, firestorms create their own wind system that keeps the fire going for a long time. The firestorms that are triggered above a certain temperature are a phenomenon that sweeps through the forest with enormous destructive elemental force.

"Fanning" substances are also hidden in the vegetation itself. The resin- and oil-rich pines and eucalyptus trees, for example, have such "fire accelerators". They also provide fuel in the trees and on the forest floor by shedding their bark.

The bark and leaves of the eucalyptus trees are so light that they can be carried up to 30 kilometers by rising winds. The burning material can then trigger so-called "spot fires" in areas that have not been spared until then. Because of this "spotting", the Australian bushfires can spread rapidly and are difficult to get under control. Up to 400 hectares are destroyed in this way in half an hour. For comparison: in a coniferous forest, just half a hectare is destroyed in the same time.

From: geoscience-online.de 2003