Various Flavors of Lightning
There are other forms of lightning in addition to
cloud to ground strikes although cloud to ground lightning is what
concerns us most. They are:
-
Cloud to
ground lightning
Cloud to ground is a dangerous form of
lightning as it can strike people, animals, buildings as well as
start fires. Only 20% of all lightning is of this
variety. It is characterized by the brilliant forked flashes
that appear to extend from the base of the cloud to the ground
surface.
-
Cloud to
cloud lightning
This displays itself as a red or yellow flash
buried in the clouds. Usually, no lightning bolt is visible,
just a glow within the cloud. The lightning can be from one
cloud to another or within the same cloud. It is actually
the most common form of lightning and, except for some radio or TV
interference, has little effect on us here on the ground.
Airline traffic, however, is very concerned with this phenomenon.
-
Positive
lightning
This form of lightning is not as common as the
cloud to ground variety although it strikes the ground as
well. It arises from the top of the thundercloud where
significant positive charge has accumulated and strikes the ground
way off in the distance, often miles from the thunderstorm, where
the ground potential has returned to it’s normally disposed
negative charge. It is actually a more dangerous form of
lightning because it occurs so far away from the storm.
Often, we have been lulled into thinking that the lightning threat
is over due to the increased distance of the thundercloud; we
resume outside activity and then out of the blue it seems,
lightning strikes.
-
Ball
lightning
This is a very rare and skeptical form of
lightning. It is believed to be non-lethal. Ball
lightning is rarely seen and the reports are of a glowing sphere
less than 40 inches in diameter. It either floats in the air
or wavers in a slow horizontal path. There are no known
photographs of such lightning, only first person eyewitness
testimony periodically through history. Because of this.,
some researchers believe that ball lightning doesn’t exist at all
and suspect that it is a an individual’s physical malady as it
bears a strong similarity to hallucinations that accompany
epileptic seizures.
Lightning Safety
Chaotic, unpredictable, and deadly, lightning is
serious business and no one is completely safe from it. Through the ages,
lightning, like passages in the bible, suffered a multitude of
misinterpretation. The key to remaining safe, or so it seems, just like
the key to obtaining eternal salvation, depends
 on
who you talk to and when! However, just because some technique has worked
well for someone somewhere, does not necessarily mean it is safe or good
enough for you or I. There is too much at stake here: personal safety,
safety of the animals, safety of the homestead,... I’ll take my cues from
the people that study thunderstorms and weather professionally. I’ll forgo
the folklore remedies that generations of old-time farmers here swear by.
Personal safety and the safety of my family and home are just too darn
important to me.
According to the National Weather Service, (NWS),
there are some things you can do to optimize your safety. They distill it
down to two primary rules and then add some refinements from there. The
primary rules are:
1. When
you first hear thunder, drop what you are doing and get inside!
Get inside a house or building, not an open shed or 3 walled structure
like a picnic shelter. . . a completely enclosed house or building and
one that has plumbing and electrical wires running through it in a more or
less conventional manner.
2.
If it is not possible to get indoors, get inside a vehicle.
This must be a fully enclosed metal one, not a convertible or a
fiberglass car; choose a metal car that has a metal roof. Roll up the
windows and don’t touch anything metal. See the sidebar entitled The
Gaussian Surface.
Let’s look at these a little more closely:
The National Oceanic and Atmospheric Administration (NOAA)
uses the slogan: “When thunder roars, go indoors!” to indicate the
primary safety route to take if at all possible. This agency encompasses
the National Weather Service (NWS), our government’s voice in issuing
vital weather related warnings and information. They take lightning
seriously and study it with tools, probes, data logging and all the
professional gadgets that we do not/would not have at our disposal.
They’ve come up with suggestions in addition to the above primary tips to
maximize your safety.
Indoors
-
Once inside, do not use
the telephone (a conventional land line); but cell phones are ok
to use. A lightning strike can travel through phone lines
and then through you to ground. It doesn’t even have to be a
direct strike as induced current from a nearby strike can kill or
injure just as easily.
-
Stay away from the bathtub, shower or any other
water-carrying fixture in the house. Your plumbing is one of the safety
paths for lightning to flow to ground. You do not want to be part of
the ground path so refrain from touching metallic faucets, sinks, pipes
or drains.
The toilet is kind
of a different animal. Most toilets are sealed porcelain
units and porcelain is a great insulator. Still, there’s
water there, inches away, and if lightning can ionize air...
Well, I won’t say anymore.
-
Electrical appliances
should be turned off. Battery operated items are ok and in
fact, very useful, especially radios to stay informed of any
weather related emergency information. It doesn’t take much
of a surge to totally destroy today’s electronic gadgetry.
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