| Hurrican(A) Essay, Research Paper
Hurricanes – weather tropical Hurricanes get their start over the warm tropical waters of the NorthAtlantic Ocean near the equator. Most hurricanes appear in late summer orearly fall, when sea temperatures are at their highest. The warm watersheats the air above it, and the updrafts of warm, moist air begin to rise.Day after day the fluffy cumuli form atop the updrafts. But the cloudtops rarely rise higher than about 6,000 feet.At that height in the tropics, there is usually a layer of warm, dry airthat acts like an invisible ceiling or lid. Once in a while, something happens in the upper air that destroysthis lid. Scientist don not know how this happens. But when it does, it’sthe first step in the birth of a hurricane. With the lid off, the warm, moist air rises higher and higher. Heat energy, released as the water vapor in the air condenses. As it condensesit drives the upper drafts to heights of 50,000 to 60,000 feet. Thecumuli become towering thunderheads. From outside the storm area, air moves in over the sea surface toreplace the air soaring upwards in the thunderheads. The air beginsswirling around the storm center, for the same reason that the airswirls around a tornado center. As this air swirls in over the sea surface, it soaks up more andmore water vapour. At the storm center, this new supply of water vaporgets pulled into the thunderhead updrafts, releasing still more energyas the water vapor condenses. This makes the updrafts rise faster,pulling in even larger amounts of air and water vapor from the storm’sedges. And as the updrafts speed up, air swirls faster and faster aroundthe storm center. The storm clouds, moving with the swirling air, form a
coil. In a few days the hurricane will have grown greatly in size andpower. The swirling shape of the winds of the hurricane is shaped like adough-nut. At the center of this giant “dough-nut” is a cloudless, hole usually having a radius of 10 miles. Through it, the blue waters of theocean can be seen. The hurricane’s wind speed near the center of thehurricane ranges from 75 miles to 150 miles per hour. The winds of a forming hurricane tend to pull away from the centeras the wind speed increases. When the winds move fast enough, the “hole”developes. This hole is the mark of a full-fledge hurricane. The hole in thecenter of the hurricane is called the “eye” of the hurricane. Within theeye, all is calm and peaceful. But in the cloud wall surrounding the eye,things are very different. Although hurricane winds do not blow as fast as tornado winds, ahurricane is far more destructive. That’s because tornado winds coveronly a small area, usually less than a mile across. A hurricane’s windsmay cover an area 60 miles wide out from the center of the eye. Anotherreason is tornadoes rarely last as long as an hour, or travel more than100 miles. However , a hurricane may rage for a week or more (example:Hurricane Dorthy) In that time, it may travel tens of thousands of milesover the sea and land. At sea, hurricane winds whip up giant waves up to 20 feet high. Suchwaves can tear freighters and other oceangoing ships in half. Over land,hurricane winds can uproot trees, blow down telephone lines and powerlines, and tear chimneys off rooftops. The air is filled with deadlyflying fragments of brick, wood, and glass.
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