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They call me the tornado chaser.
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When the wind is up
and conditions are right,
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I get in my car and follow violent storms.
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"Crazy," you say? Perhaps, but really I
chase these sky beasts to learn about them.
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I want to share with you what I know.
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Tornadoes are rapidly rotating columns
of air that form inside storms
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that connect with the ground via
a funnel of cloud.
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When that happens,
they tear across the Earth,
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posing a huge threat to life and property.
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Because of this, there's a great deal
of research into these phenomena,
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but the truth is, there's still a lot
we don't know about how tornadoes form.
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The conditions that may
give rise to one tornado
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won't necessarily cause another.
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But we have learned a lot since
people first started recording tornadoes,
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like how to recognize the signs
when one is brewing in the sky.
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Are you coming along for the ride?
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Tornadoes begin with a thunderstorm
but not just any thunderstorm.
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These are especially powerful, towering
thunderstorms called supercells.
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Reaching up to over 50,000 feet,
they bring high force winds,
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giant hailstones, sometimes flooding
and great flashes of lightning, too.
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These are the kinds of storms
that breed tornadoes,
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but only if there are also very
specific conditions in place,
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clues that we can measure and look out for
when we're trying to forecast a storm.
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Rising air is the first ingredient needed
for a tornado to develop.
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Any storm is formed
when condensation occurs,
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the byproducts of the clouds.
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Condensation releases heat,
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and heat becomes the energy that drives
huge upward drafts of air.
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The more condensation
and the bigger the storm clouds grow,
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the more powerful those updrafts become.
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In supercells, this rising airmass
is particularly strong.
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As the air climbs, it can change direction
and start to move more quickly.
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Finally, at the storm's base,
if there is a lot of moisture,
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a huge cloud base develops,
giving the tornado
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something to feed off later,
if it gets that far.
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When all these things are in place,
a vortex can develop enclosed by the storm,
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and forming a wide, tall tube of spinning
air that then gets pulled upwards.
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We call this a mesocyclone.
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Outside, cool, dry, sinking air
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starts to wrap around the back of
this mesocyclone,
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forming what's known as a
rear flank downdraft.
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This unusual scenario creates
a stark temperature difference
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between the air inside the mesocyclone,
and the air outside,
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building up a level of instability
that allows a tornado to thrive.
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Then, the mesocyclone's lower part
becomes tighter,
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increasing the speed of the wind.
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If, and that's a big if,
this funnel of air moves down
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into that large, moist cloud base
at the bottom of the parent storm,
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it sucks it in and turns it
into a rotating wall of cloud,
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forming a link between
the storm that created it and the Earth.
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The second that tube of
spinning cloud touches the ground,
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it becomes a tornado.
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Most are small and short-lived,
producing winds of 65-110 miles per hour,
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but others can last for over an hour,
producing 200 mile per hour winds.
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They are beautiful but terrifying,
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especially if you or
your town is in its path.
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In that case, no one,
not even tornado chasers like me,
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enjoy watching thing unfold.
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Just like everything, however,
tornadoes do come to an end.
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When the temperature difference disappears
and conditions grow more stable,
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or the moisture in the air dries up,
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the once fierce parent storm loses
momentum and draws its tornado back inside.
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Even so, meteorologists and storm chasers
like me will remain on the lookout,
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watching, always watching to see
if the storm releases its long rope again.