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Lightening
#11
I was told by my contractor:

The soil in Hawaii has a large glass component, glass is an insulator.

consequently when there is a cloud to ground strike the lightning ball "hops" around as it tries to find a ground. This also explains why code out here requires more grounding rods, be aware of that as you add cable, telephone and antennas. Ground, ground, ground if you do not want that lightning ball hoping from appliance to appliance - heads up you off grid folks who do not have a helco approved grounding system to piggy back on ... make sure your genset, solar etc is well grounded
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#12
Also when unplugging the computer don't forget to undo the modem/phone or cable line.

Small kid time we had a barn with a lightening rod on top of it. Don't think it ever actually got hit, but it might be a useful thing to have just in case.

"I like yard sales," he said. "All true survivalists like yard sales." 
Kurt Wilson
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#13
Then there was Mr. Sullivan

struck 7 times -

http://en.wikipedia.org/wiki/Roy_Sullivan
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#14
Bullwinkle, the ROCK on this island is high in amorphous solid (a non-crystalline solid that is sometimes referred to as "glass" by some scientists...)
Basalt here is actually very low in silica (the common element in that transparent product called "glass") and high in iron oxides and manganese oxides.
Basalt rock is actually a mediocre insulator, and some flows actually have conductive properties....
Of course, the soil near you may actually be high in glass, bottle type glass, but that is a fairly shallow phenomenon, geologically....
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#15
Regarding the lightening, must have been very impressive as it blew out Pu'u O'o's web cam!

From HVO 2008/04/10 our telemetry was disabled during a recent lightning storm. We are working to correct the problem.

Glow from crater in Volcano very impressive this am also.

mella l
mella l
Art and Science
bytheSEA
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#16
Hawaii (and Alaska) have the least amount of casualities (injuries and deaths)from lightning and Hawaii has 0 deaths ( I think in half a century - different Web page than this one) out of the United States.
http://www.nssl.noaa.gov/papers/techmemo...193-3.html
And it's not that we have less people:
http://en.wikipedia.org/wiki/List_of_U.S...population


Cindy







http://www.CoconutRoads.com
"Taking you to the Heart of Hawaii"
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#17
"Bullwinkle, the ROCK on this island is high in amorphous solid"
thanks for the heads up - I have a lot of that green mineral in the rock - Olivine or Chrysolite - empirically it strikes me as an insulator...

I does make me feel better to have lots of ground rods. Having come off a sail boat with a 50 foot aluminum mast overhead wherever I went -- I have have become very, very, nervous in regions that have thunderstorms! (and low power wires in marinas, I have a buddy that hit a 20kv line with his) - Zap!
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#18
Water in the soil & rock (aquifers) is a good conductor, so if the ground is saturated, the soil/rock will actually be a fairly decent conductor....
lucky thing here is that most of the time the ground is NOT saturated (some areas during the flood were saturated a couple of months ago...)
As for the low deaths...
Lightning is a relatively rare event in Hawaii. A good map of Lightning occurance worldwide is from "wikipedia":
http://en.wikipedia.org/wiki/Lightening
Interesting note: that article also notes that lightning can be discharged in volcanic eruptions.....due to the static discharge from the volcanic ash! oh Brianna!
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#19

"Hawaii (and Alaska) have the least amount of causalities (injuries and deaths) from lightning...."

This may have something to do with the relative scarcity of people standing out in the middle of lawns waving metal lightning rods over their heads on golf courses in Alaska and Hawaii versus in the mainland Lower 48 states. Wink

A month or so ago I asked our draftsperson and contractor to please be sure they have a good quality lightning rod and grounding system in the design for the two-story steel frame structure we are building. A combination of thorough grounding for the frame and electrical system PLUS a well insulated and well grounded lightning rod and discharge cable appears to be the best route for us (http://www.lightningsafety.com/nlsi_lhm/...lRods.html).

To retrofit an existing building with better protection perhaps mounting one of Ben Franklin's rods would be useful, given that it is blunt-tipped (see http://www.usatoday.com/weather/resource...-tests.htm ), properly installed on a low-risk day, and well-grounded. Here are some links for outfits selling them-

http://www.elec-toolbox.com/usefulinfo/lightprot.htm
http://www.kuefler-lightning.com/?gclid=...awodj1dk-g
http://www.lightningrodman.com/equip.php
http://www.lightningrod.com/
http://www.lightningrodparts.com/

I have not yet had dealings with any of these companies but have been looking at what they offer for the sake of comparison. If anyone has any recommendations on a make, manufacturer, and/or supplier of blunt-tip lightning rod systems then please do post word of your experience.

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#20

This news report could have some potential prevention value for Puna.

The portions which seem useful to me are the points:

-as storm frequency and severity globally increase due to shifts in climate (more energy trapped inside the atmosphere by the greenhouse gases), local weather may reflect this change via more frequent lightning strike activity than was historically common, and

-anything metal can serve as draw for attracting a lightning strike, especially if on a beach or working with metal tools out in a garden patch or agricultural field; in this context the wires running from an iPod to a listener's ears are also an antenna potentially attracting a lightning strike


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Gadgets blamed as lightning strikes dozens

From Alina Selyukh
CNN

MOSCOW, Russia -- Lightning has killed and injured more than a dozen people in Russia in the past two weeks, officials say, blaming widespread use of electronic gadgets such as cell phones for an increase in deadly strikes.

On Wednesday, a lightning bolt killed three sunbathers in the town of Neftekamsk, 800 miles east of Moscow.

One victim, Marina Sadykova, 26, was among a few people on a beach along the Kama River when a storm moved in. Witnesses said they saw a sharp, blinding ray of light that raised 7.6 meters (25 feet) of sand.

The woman -- mother of a 5-month-old boy -- was talking on a cell phone when she was killed, and the phone was found melted in her hand, according to police.

Russian media have reported similar instances across central Russia, including the death of a 10-year-old boy on a bike, a young man talking on a cell phone and an elderly farmer tending her potato plants.

Leonid Tarkov of the weather observation center FOBOS said he believes that the surge in lightning strikes may be connected to the increased use of portable electronic technology, such as cellular phones or music players.

"These things are electromagnetic field carriers," he said. "That makes them, in essence, conductors. Thunderbolts are frequently attracted to such things, and hits are often connected with a lethal outcome."

The idea that lightning can follow the weak electromagnetic fields of such devices is rejected by virtually all scientists, although there is evidence that a lightning strike is more likely to be fatal for a person carrying any object with metal in it.

And Tarkov himself pointed out another explanation for the surge in lightning strikes in Russia this summer: The country has been hit by an unusually high number of storms.

He said Moscow is 139 percent above normal for rainfall this month, including 51 millimeters (2 inches) from a fierce thunderstorm Wednesday, the equivalent of five buckets of water on each square meter.

"The absolute July maximum was observed in July 1965, when 184 millimeters (7.24 inches) of precipitation fell on Moscow," he said. "If such weather continues, it's not unlikely for the absolute maximum to be topped."

Storms left dozens of houses across Central Russia without electricity or water, and lightning ignited fires that burned a number of them, according to media reports.

More than a hundred trees were reported felled by winds in Moscow on Thursday night, and traffic was regularly stalled by flows of water during the past week. Thursday's storm also cut power to the rails used by public transportation, halting movement for more than an hour. Dozens of frustrated passengers who missed their flights are still in Moscow.

Russia's stormy weather is likely to last at least another week, Tarkov said. He cited contrasting weather in the central region as the cause: A vast anticyclone that has settled over the area first carries cool humid North Atlantic winds and, hours later, subtropical heat.

"This only happens once in five to seven years," Tarkov said. "We haven't had such intensive storm activity in a while."


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Astonishing skill! This archer is a real-life Legolas and then some!
http://geekologie.com/2013/11/real-life-...rs-anc.php

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