> Below is a cache of http://www.tbp.org/pages/Publications/Bent/Features/W0Bell5.pdf. It's a snapshot of the page taken as our search engine crawled the Web.
The web site itself may have changed. You can check the current page or check for previous versions at the Internet Archive. Yahoo! is not affiliated with the authors of this page or responsible for its content.
BENT_p15-22.featLightning W
INTER
2005


T
H E
B
E N T O F T A U B E T A P I
15
phone was cooked. Throughout the house, several electric
fans, nightlights, and dimmer switches were stone dead.
Outdoors, the automatic garage door had frozen a foot above
the concrete floor and no longer responded to the hard-
wired button from the kitchen or the radio-acti-
vated remote controls. Most tellingly, on the roof
directly above my office and bedroom, the taper-
ing concrete upper part of the chimney had been
sheared in two, and concrete chunks lay around
my driveway.
Lightning had struck my house.
As curious neighbors paraded through to see
what lightning damage looked like, followed by in-
surance adjustors and workmen giving estimates,
it seemed everyone either had a personal lightning-
damage story or directly knew someone with a
story. One had a computer zapped when lightning
struck several houses away. Another had nearly
been struck as a teenager playing ball during a
BANG! BANG!
A quarter to three on the morning of August 26, 2003, in the
midst of an unusually violent thunderstorm that had my 12-
year-old daughter Roxana quivering against me, came two
fast blinding flashes and simultaneously two fast, deafening
cracks like a rapid pair of cosmically loud pistol shots. My
God, that was close! I exclaimed, watching the nightlight
across the second-floor bedroom flicker, fade, and die. Just
how close was it?
When I walked downstairs at dawn as usual to check my
email, my freelance writers office looked as though a small
bomb had exploded in the fireplace. Its brass frame had been
blasted out of its three-inch masonry bolts and one of its
glass doors launched 10 feet away. The foot-wide inch-thick
marble slabs on the sides of the fireplace had been blown
out to a 45 degree angle, one of them split in half [Fig. 1]. Soot
and gray plaster/brick/concrete grit coated carpet, curtains,
computer, desk, papers, books, and vertical files, and a burnt
smell permeated the large room. Fortunately for me, the
computer booted normallypraise be to its battery-backup
uninterruptible power supply/surge protector (UPS)but
the UPS itself had taken a hit through the phone line, be-
cause the computers modem could not get a dial tone
through its jack. My color inkjet printer/scanner/photocopier
was totally dead; my black-and-white laser printer would
turn on, but not respond to print commands.
Nor was the damage limited to my office. In the kitchen,
my microwave oven was fried. Upstairs, the cordless tele-
Figure 1 Lightning struck the authors chimney on August 26, 2003,
shearing the masonry holding the metal damper (upper left), and blasting
a fireplace into a first-floor office (lower
right). The strike also fried the automatic
garage-door opener mechanism (lower left)
and appliances throughout the house.
A powerful electrical storm created an eerie tapestry of light in the
hours preceding the launch of STS-8, August 31, 1983 at Kennedy
Space Center.
© 2004
TR
UD
Y E.
BELL
Struck by Lightning
by
Trudy E. Bell
If you think your odds of winning the lottery are about the same as getting
...think again... 16
W
INTER
2005


T
H E
B
E N T O F T A U B E T A P I
thunderstorm in a half-flooded field. A third felt his hair
curl over his entire body just before a bolt cleaved a tree
outside the window, not 10 feet away. The chimney brick-
layer himself was working simultaneously on another house
15 miles east of mine that had been struck in the same storm
that had struck mine. A month after my experience,
Clevelands Plain Dealer ran an essay by a local woman
shaken by the experience of seeing her living room wall
punctured by a lightning bolt that entered and exploded
her television set without disturbing anything else.
Advice came fast and contradictory. Should I put up
lightning rods? I asked the electrician. Immediately he
shook his head and responded: Absolutely not! Lightning
rods actually attract lightning! And no one could answer
my basic question: Why did the lightning strike my house
instead of any of the much taller trees nearby? The best
answer was harrumphed by one insurance adjustor whod
seen it all: Lightning does what it wants to do. Theres no
accounting.
If you live through it, write about itthats my
journalists motto. And since no one seemed to have straight
answersat least not ones satisfying to someone with sci-
entific curiosityit was clear there must be a story in the
frequency and physics of lightning strikes.
WHAT ARE THE ODDS?
The single most astonishing fact is just how often lightning
strikes the earth. Numbers vary widely with the source,
but the order of magnitude is clear: ever since the National
Lightning Detection Network across the continental United
States was installed in 1989 by Global Atmosphericsnow
the worldwide Vaisala Group, headquartered in Finland
something like 20 to 25 million cloud-to-ground flashes are
detected annually over the nation. Because about half of
lightning bolts are forked, that means lightning strikes more
than 30 million points in the U.S. each year. That trans-
lates into a nationwide annual average of some four strikes
per square kilometer or 10 per square mile. True, arid desert
areas suffer fewer strikes, but subtropical Florida is the
all-American capital, annually averaging 10 strikes per
square kilometer or more than 25 per square mile [Fig. 2].
Nationwide, the prime lightning season extends from May
through September, although lightning has been known to
occur in winter snowstorms. Worldwide, Central Africa,
parts of Southeast Asia, and mountain regions of Latin
America attract double or triple the amount of lightning as
central Florida [Fig. 3].
You and Roxana are unbelievably lucky that you
werent hurt or killed and that your house wasnt set on
fire! exclaimed a friend upon hearing my account. Were
we ever. My house has two chimneys; the one the lightning
struck runs down the wall at the head of my bed, because
my bedroom is directly above my office.
National Weather Service statistics kept for more than
half a century reveal that on an annual average more people
are killed by lightning than by tornadoes, floods, or hurri-
canes [Table 1]. (The single largest category of victims is
golfers, because they are often the tallest beings in wide,
flat terrain or they huddle for shelter under lone trees that
may draw lightning; golfers alone account for more than
six percent of victims.) But fatalities comprise only 10 per-
cent of people actually struck by lightning. About 1,000 a
year across the United States live through the experience
but suffer burns, cataracts, or more debilitating neurologi-
cal injuries; one common injury is hearing loss from the
acoustic shock of accompanying thunder, which can reach a
pressure of 10 atmospheresenough to burst eardrums.
The top of a
large thunder-
storm, roughly
20 km across, is
illuminated by a
full moon and
frequent bursts
of lightning.
These two
images were
taken nine
seconds apart
as the STS-97
Space Shuttle
flew over
equatorial
Africa east of
Lake Volta on
December 11,
2000. Because
the shuttle
traveled at
seven km/sec,
the astronauts
perspective on this storm system became more oblique over the
interval between photographs. The images were taken with a Nikon
35mm camera equipped with a 400mm lens and high-speed (800 ISO)
color negative film.
Fatalities: 1990-2003
rank
1 - 10
11 - 20
21 - 30
31- 52
Flash Density
flashes/sq. km/yr
8 - 16
2 - 4
.5 - 1
.25 - .5
Figure 2
Approximately 22
million lightning
flashes occur over
the U.S. per year,
amounting to about
30 million cloud-to-
ground strikes
because half of
lightning is forked.
Most lightning occurs
over the midwestern
and southeastern
states, with Florida
the nations lightning
capital, averaging
more than 25 strikes
per square mile per
yearthree times the
national averageas
well as a dispropor-
tionate one-sixth of
the nations lightning
fatalities. W
INTER
2005


T
H E
B
E N T O F T A U B E T A P I
17
INSURING THE RISK
Far more common than deaths or injuries from lightning is
property damage. According to Richard Kithil, founder and
CEO of the National Lightning Safety Institute, Louisville,
CO, about one house in 200 is struck per year. As nearly as
I can calculate, that means that over a lifetime of home own-
ership the odds of a house being struck by lightning exceed
the lifetime odds of a womans getting breast cancer. Ac-
cording to various insurance sources, lightning damage
amounts to nearly five percent of all paid insurance claims
nationwide each