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All About Hurricanes
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Which of the following describe hurricanes ?
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Hurricane, cyclone, typhoon, these are all describing the same thing, a powerful wind and rain storm that can tear apart houses and flood entire cities.  Even though the name is different, they have the same make up, need the same conditions for formation, and cause the same damaging side effects.Relatively simple in composition, what we are going to refer to as a hurricane is made up of a low-pressure center called ‘the eye’ and a spiral arrangement of thunderstorms extending from its center.  To make this particular combination occur, there are several natural factors that need to be present in the environment.First, wind conditions are only suitable from roughly latitude 5° and 20° North and South of the Equator, where the Coriolis Effect, the force which causes rotary motion in winds, is strong enough to cause rotation.  Typically, the conditions are not right from 0° to 5° North and South.Second, you need the right wind conditions, meaning the temperature in the atmosphere must at greatest difference from the sea surface temperature.Third, the water needs to be warm, at least 79.7 degrees Fare height at a depth of 160 feet. Finally there needs to be a disturbance in the atmosphere.  When these factors are presents, a storm is capable of forming.These storms are classified by wind speed, and begin at 38 miles per hour as a tropical depression.  A tropical depression becomes a hurricane at 74 miles per hour, and from there the wind speed is measured on a scale of 1 - 5, with a category five hurricane beginning with wind speeds of 150 miles per hour or more.When in the path of a hurricane, it is important to pay attention to both the storm itself and its associated affects, including storm surge, wind damage, and freshwater flooding.Storm surge is the rising of the sea as the low-pressure system moves towards the shore, this can cause massive flooding of coastal and low lying areas.Wind damage results from not only the force of extreme winds against a structure, but also the debris that is carried along in the wind crashing into homes and businesses.Freshwater flooding results from high levels of rain overflowing nearby rivers and lakes.From the relatively low damage caused by tropical depressions to the hundreds of millions of dollars of damage caused by hurricanes, the effects of one of these storms can destroy communities and lead to high causality rates.Thanks for watching.  For more information, please see About.com
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