Hi Jim,
> There are reports from trained observers...amateurs with multi-tower
> installations...who have observed storms with frequent cloud to ground
> lightning, where that lightning ceased when near the antenna field, and
> resumed after passing it. So, I am inclined to believe that a well
>grounded tower system, with or without pointy things, will tend to reduce
the
> resistance in the cloud to ground circuit.
I am going to cast doubt on that conclusion. I do not doubt that people
actually saw what they saw, but I SERIOUSLY doubt that the storms
behaved differently BECAUSE the antenna system was well-grounded.
Thunderstorm behavior is often unpredictable because of invisible phenomena
occurring on a MINUTE scale over areas as small as a few hundred yards!
The presence or absence of trees, hills, and small differences in air temp,
air moisture, low level gravity waves, winds and other factors, ALL
INVISIBLE, can make an
incredible difference on a VERY localized weather event.
The movement of storms is not uniform either, as "tracks" set up and
disappearwithout notice or warning and often contribute to the exacerbation
or
mitigation of small-scale weather phenomena.
On my hill, which is maybe a 1/2 mile wide AT THE MOST, some days the storms
"part" and then reform on the other side, sometimes they don't climb the
hill (just 300' vertical feet) and blast a spot 3/4 mile South, sometimes
they stay on
the West side of the hill and blast a spot 1/2 mile North of me, etc. I can
always see these storm
clouds, and the cloud swirls and rotation of the winds. Often the winds
blow in one
direction at ground level and a completely DIFFERENT and sometimes OPPOSITE
direction
less than 1000' up!
ALL these factors and many others contribute, especially very small-scale
geography. This all plays an enormous factor in what I observe and what
others can and
have observed.
Meteorologists have recently been able to observe the effects of multiple
vortices within tornadoes and hurricanes that explain why one house can be
destroyed and
another house 100' away can be almost untouched in the middle of a monster
storm.
Microbursts are another VERY small-scale phenomena with often catastrophic
results, as are straight-line winds. ALL of these phenomena and others can
be
present in a T-storm - even a very small one, and what someone sees and
experiences in
the WRONG place can be amazingly different that what is seen and experienced
1/2 mile
away.
I have no doubt that these phenomena, of which we are still largely
ignorant, explains a lot of what others have experienced and seen.
I remember living in Ithaca, NY for 4 years while attending Cornell (and
studying WX among other things) and repeatedly witnessing the snow squall
clouds break
up over certain spots and reform less than 1/2 mile away with incredible
difference in
snowfall!
What SPECIFIC direction the wind was coming from was a large determinant in
whether or not the clouds broke up and where they would reform. Altitude
and local
geography also played a huge role in this phenomena. Similar things
occurred with
Summer T-storms.
Where there is varying geography and where terrain influences low-level wind
and moisture patterns, you can have dramatic WX phenomena that changes
quickly and
unpredictably and may explain a lot of what is seen. But a good tower
ground CAUSING a
T-storm to break up and reform on the other side? NO WAY!
73
Bob KQ2M
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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