| themes & topics | (C) 2003 Meridian Communications, Inc., publisher of KnowledgeNews. For more knowledge behind the news, go to http://knowledgenews.net. |
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Hurricanes vs. Tornadoes vs. You |
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Hurricane Isabel proves once again that nature has a
thousand ways to kill you. Wind, earthquake, volcano, drought, flood, fire,
you name the place and choose the form of destruction, and nature has an
unequivocal way to show who's boss.
In North
America, the warm weather brings disaster by air, by hurricane and tornado.
Tornadoes can strike anytime, but occur most frequently in spring and
early summer. Hurricane season picks up where tornadoes leave off, running
June through November. Both are awesome forms of windpower that represent
nature at her fiercest. But which is
meaner? Which is deadlier? Which is the baddest atmospheric force on Earth?
We've matched these two forces head-to-head and broken them down with some
scientific facts to determine which is the true king of disaster in the
sky |
Isabel attacks |
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Wind Speed |
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Tornadoes
- Packed into tight, swirling spirals of power, the winds of the most
powerful (F5) tornadoes can reach speeds approaching 320 miles (515
kilometers) per hour--the most violent winds on Earth. Just how fast is
320 miles per hour? It's faster than a Formula One race car, faster than
many airplanes can fly, and almost half the speed of sound. At that speed,
wind can fling cars across football fields and reduce the sturdiest house
to rubble. The vast majority of tornadoes, however, rage at less than 200
miles (322 kilometers) per hour. That's still fast enough to uproot trees
and destroy your average mobile home. |
Hurricanes
- A stiff breeze of, say, 30 miles (48 kilometers) per hour will blow your
trusty umbrella inside out, sweep the hat off your head, and make it hard
to walk upwind. Now triple that speed, and you've got a hurricane on your
hands--a weak one. If you wanted a strong hurricane, you'd have to whip up
sustained winds of over 150 miles (241 kilometers) per hour, with gusts
that top 200 miles (322 kilometers) per hour. At hurricane wind speeds,
loose debris becomes a barrage of flying missiles. Even if you could
stand up straight in a hurricane wind, it wouldn't be a good idea. |
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Advantage: Tornadoes. |
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Size |
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Tornadoes
- Tornadoes are quite small as atmospheric phenomena go. The width of the
funnel at ground-point usually ranges from a few dozen to several hundred
yards (or meters) across. The largest tornadoes reach more impressive
widths--more than a mile (1.6 kilometers) at ground-point. Yet because
tornadoes move rapidly along the ground, they can cause damage over a
larger area than their small size might suggest. Larger, longer-lived
tornadoes can cut a swath of destruction several hundred miles long before
disappearing into the sky. |
Hurricanes
- Hurricanes are huge; they can cover entire states. One look at a
hurricane through a satellite photo shows just how big they can be. The
average hurricane is 200 to 300 miles (322 to 483 kilometers) in diameter,
and massive hurricanes can span 700 miles (1,127 kilometers) or more. The
size of a hurricane, however, is not directly related to its wind speed or
destructive force. Relatively small ones have packed an incredible punch,
while much larger ones have been relatively mild. |
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Advantage: Hurricanes. |
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Frequency
and Range |
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Tornadoes
- Tornadoes tend to occur over flat terrain, but can travel across
mountains and form over water. In 1997, a tornado even passed through the
heart of downtown Miami. Although they're found in places like India,
Europe, and Australia, tornadoes are most common--and most powerful--in
the United States. Tornadoes can form year-round, but most occur in a
"tornado season" of March through May and through the summer in
more northern states. A typical year will see close to 800 tornado reports
in the U.S. and a much higher number worldwide. |
Hurricanes
- Because they require the tropical ocean to maintain their intensity,
hurricanes quickly lose their strength when they make landfall or move
into cooler climates. This greatly limits the number of places that run
the risk of being struck. The same factors that spawn hurricanes also
limit their frequency. Like tornadoes, hurricanes tend to strike in season,
which in the Atlantic is from June through November. On average, only a
dozen hurricanes a year are spawned there, and many of those never strike
populated areas. |
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Advantage:
Tornadoes. |
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Damage |
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Tornadoes
- Tornadoes pack quite a wallop, and when they strike near populated areas,
the damage can be severe. Due to their size and behavior, most damage is
localized and random. Tornadoes are notorious for destroying some houses
while leaving those across the street virtually untouched. The biggest
tornado outbreak in the last century--the "Super Outbreak" of
April 3-4, 1974--spawned 148 tornadoes across 13 states and caused damage
in excess of $600 million, $100 million of which resulted from a massive
tornado that destroyed half the town of Xenia, Ohio. |
Hurricanes
- Because of their immense size and longevity, hurricanes can wreak
tremendous havoc. The combined effects of wind, rain, and surf can destroy
homes, erode seashores, and flood entire cities. Luckily, most hurricanes
spend the majority of their life in the open ocean. Just how much damage a
hurricane does is determined as much by when, where, and how long it
strikes coastal areas as by the magnitude of the storm itself. When
Hurricane Andrew, for example, struck both south Florida and Louisiana in
1992, it caused total damage estimated at $36 billion. |
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Advantage:
Hurricanes. |
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Deaths |
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Tornadoes
- Tornadoes are powerful killers. Although they are capable of lifting
humans into the air and hurling them long distances, flying debris and
collapsing buildings cause most deaths. Unfortunately, in spite of greatly
improved weather tracking and warning systems, tornadoes still kill an
average of 100 people in the Unites States each year. The worst event on
record is the Great Tri-State Tornado of March 18, 1925, a mile-wide
monster that tore across 219 miles (352 kilometers) of Missouri, Illinois,
and Indiana, killing 695 people, injuring 2,207, and destroying more than
15,000 homes. |
Hurricanes
- Improved weather tracking and warning systems have greatly reduced the
number of deaths caused by hurricanes. The 1928 hurricane that struck Lake
Okeechobee in Florida killed 1,836 people. Estimates from earlier storms
point to several that killed even more. Even with modern satellite
tracking and early evacuation plans, Hurricane Floyd caused 56 deaths in
1999. And not every place has such modern tools. In 1991, a typhoon (as
hurricanes are called in the western Pacific and Indian oceans) struck
low-lying sections of Bangladesh and killed almost 140,000 people. |
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Advantage:
Hurricanes. |
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Power |
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Tornadoes
- Yard for yard, tornadoes pack the most destructive force of any
atmospheric phenomenon, possessing a pinpoint violence unmatched by any
other force of nature. In fact, a good-sized twister releases energy at a
rate equal to that of two large nuclear reactors. Don't be too impressed,
though. The "supercell" thunderstorms that spawn tornadoes
typically have a total energy output thousands of times greater than that. |
Hurricanes
- The sheer size of a hurricane allows it to unleash massive amounts of
destructive power on anything unfortunate enough to be engulfed by it. And
unlike tornadoes, which rarely last for more than an hour, a hurricane can
rage for days. All of that adds up to staggering energy levels. By some
calculations, a typical hurricane generates power at a rate equal to that
of half of the electrical production of the entire world at any given
time. |
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Advantage:
Hurricanes. |
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Intangibles |
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Tornadoes
- In spite of their destructiveness, tornadoes fascinate. Every year,
hundreds of people, from meteorologists to nature photographers to the
merely curious, go storm-chasing across the countryside in an effort to
measure, document, or simply witness tornadoes' breathtaking power. For
whatever reason, the sight of a funnel cloud in the sky often sends folks
running for their cameras before running for their lives. |
Hurricanes
- Though they certainly goose the Weather Channel's ratings, hurricanes
don't have the cinematic, visual appeal of tornadoes, probably because
they're just too large to be seen in their entirety. It wasn't even until
humans went into space and looked down on these storms from above that
their magnitude could truly be appreciated. The experience of being in
one, however, leaves little to the imagination. |
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Advantage:
Tornadoes. |
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And
the Winner Is . . . Hurricanes. Both hurricanes and tornadoes are amazing, they're
both deadly, and they're both destructive. But in this case, size does
matter. Tornadoes may be more visually spectacular, and evoke more popular
excitement and interest, but the sheer magnitude and power of the
hurricane is unmatched among nature's skyborn forces. Christopher Call |
"(C) 2003 Meridian Communications, Inc., publisher of KnowledgeNews. For more knowledge behind the news, go to http://knowledgenews.net."
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