In a recent science channel show there is a couple of shots describing most
lightning striking initialy from the ground up. There are "streamers" or
fingers of modest electron flow from the ground which actually initiates the
strike. Comments from the "experts" claimed every thing from a grounded
structure can actually cause lightning to develop from its ground, to the good
grounds dissipate the charge and help prevent lightning.
They also shot small rockets trailing a grounded wire into clouds and caused
strikes, and in some of those the initial strikes is from the ground up not
going from the cloud to the earth. They also showed a couple of different
types of lightning such as some really incredibley powerful strikes ( several
hundred times the ground strikes , called super lightning) between two
clouds, also going from the bottom cloud to the top cloud, and several other
phenomena such as st. elmos fire , and lightning strikes on aircraft, which
usually
cause very little damage considering what could be possible
So bottom line is the jury is still out on a lot of stuff we don't know
about lightning in general, how it decides to strike, how it strikes, and such.
The photography showing a strike orignating from the ground up was astounding,
you could actually see small tendrils of lightning ( current, power??) form
from the ground and reach up and as they approched the cloud the strike jumped
from the cloud to the tendril and then down.
Thank goodness we only deal with those here in northern california
infrequently. Usually only a couple to 4 or 5 bad thunder and lightning storms
per
year here, and those usually well in the distance.
Remember light travels at 186,000 miles per second ( almost instantanious)
and sound travels in air at about 1100 feet per second, so when you see the
flash, count "one thousand and one, one thousand and two, and for every 5
seconds, the lightning is a mile away, so if you make it to one thousand and
fifteen, the strike was roughly 3 miles away. a fun tidbit.
tom N6AJR
In a message dated 7/1/2005 7:24:23 A.M. Pacific Standard Time,
rdetweil@hotmail.com writes:
Reminds me of the phrase, "Lightning follows the path of least resistance."
>
>That phrase is true but I believe lightning follows all the other paths,
>too.
>
>73, Mike N4NT
>
Well, if the ground system can handle the current load of a lightning
strike, then like water, it's not going to flow up hill, If the ground
system can't handle the current, then it will backup just like a dam and
flow into everything else.
If I had it to do over, I'd still add more stuff in my ground system..
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