Hurricanes Essay, Research Paper

Hurricanes get their

start over the warm tropical waters of the North

Atlantic Ocean near the equator. Most hurricanes

appear in late summer or early fall, when sea

temperatures are at their highest. The warm waters

heats 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 cloud tops

rarely rise higher than about 6,000 feet. At that

height in the tropics, there is usually a layer of

warm, dry air that acts like an invisible ceiling or

lid. Once in a while, something happens in the

upper air that destroys this lid. Scientist don not

know how this happens. But when it does, it’s the

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 condenses it drives the upper

drafts to heights of 50,000 to 60,000 feet. The

cumuli become towering thunderheads. From

outside the storm area, air moves in over the sea

surface to replace the air soaring upwards in the

thunderheads. The air begins swirling around the

storm center, for the same reason that the air

swirls around a tornado center. As this air swirls in

over the sea surface, it soaks up more and more

water vapour. At the storm center, this new supply

of water vapor gets pulled into the thunderhead

updrafts, releasing still more energy as the water

vapor condenses. This makes the updrafts rise

faster, pulling in even larger amounts of air and

water vapor from the storm’s edges. And as the

updrafts speed up, air swirls faster and faster

around the 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

and power. The swirling shape of the winds of the

hurricane is shaped like a dough-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 the ocean can be seen. The hurricane’s

wind speed near the center of the hurricane ranges

from 75 miles to 150 miles per hour. The winds of

a forming hurricane tend to pull away from the

center as 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 the center of the hurricane is called the

"eye" of the hurricane. Within the eye, 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, a

hurricane is far more destructive. That’s because

tornado winds cover only a small area, usually less

than a mile across. A hurricane’s winds may cover

an area 60 miles wide out from the center of the

eye. Another reason is tornadoes rarely last as

long as an hour, or travel more than 100 miles.

However , a hurricane may rage for a week or

more (example: Hurricane Dorthy) In that time, it

may travel tens of thousands of miles over the sea

and land. At sea, hurricane winds whip up giant

waves up to 20 feet high. Such waves can tear

freighters and other oceangoing ships in half. Over

land, hurricane winds can uproot trees, blow

down telephone lines and power lines, and tear

chimneys off rooftops. The air is filled with deadly

flying fragments of brick, wood, and glass.