Tinkerntom wrote:
Brian, I live here in Denver, the High Plains, and called the
lightening capitol. I have heard about squatting on your mat for
insulation, and personally I think that rates up there with "duck and
cover". You are in the correct position to bend over and Kiss your Ass
goodbye! Lightening after it has traveled through 20 - 50 miles of
atmosphere does and goes where lightening wants, and a half inch of
foam padding is not going to make much difference, unless it makes you
feel more comfortable.

There are two reasons for the insulating mat. The first is not to stop
the lightning discharge once it has started, but to help make you a less
attractive target so the lightning is less likely to "want" to go there.

When the clouds overhead pass by with their electrical charge, they
attract the opposite charges in the ground which then travel up anything
elevated and start discharging into the air. This is why people in the
middle of lightning storms sometimes report feeling their hair standing
on end as the charges discharge from the strands of hair - and is a good
indication that you're in a very unsafe spot. Even a little insulation
can greatly reduce the amount of charge that can enter your body from
the ground during this period preceding the lightning strike and can
help make you a less attractive target than some tree or bush that is in
better electrical contact with the ground and is therefore concentrating
a large charge opposite (and therefore attractive) to that of the clouds.

The second, and probably more important, benefit of the mat comes in the
event that lightning does hit somewhere near you. In that case
electrical currents will flow outward through the surface of the ground
and any two points on the ground will have a voltage difference given by
the current flow times the resistance of the ground between those points
(Ohm's law). Keeping your contact points with the ground (or mat) close
together as you do in a squat is therefore recommended since it
minimizes that voltage difference. At this point the insulating mat
results in making the ground the path of least resistance so the current
tends to flow under you rather than up through your body. You don't
want your hands or any part of your upper body to be contacting the
ground (or mat) so any current that does still flow through you only
goes between your legs and doesn't pass through your heart.

"Brian Nystrom" wrote in message
...
skip wrote:
Thanks for the comments and suggestions.

What we actually did was to spread out and paddle like hell for 15
minutes to a point where there was land. This did in fact warm up the
sit on top paddler who was without rain grear. When we reached land
there was a couple there who had started a small fire under a Plametto
tree. We huddled there in fear and trembling until the thunder and
lightning passed and then paddled on to the take out in the rain
(pleasant for me with my spray skirt, paddling jacket, and Gore Tex hat).

Huddling together was a bad idea. Once on shore, you should spread out.
That minimizes the likelihood of more than one of you being struck.

We used that logic going down river, but it went out the window as soon as
we saw the fire under the palmetto tree - except, that is, for one person
who stayed apart from us for a while, but soon gave in and joined us.


We all had dry clothes, but they were useless in the downpour. No one
brought extra rain gear. I have a space blanket, but it was underneath
my sleeping pad in the tent. Before I go out again I'm going to pick one
up for the boat.

While space blankets are certainly useful items in their own right, you
might want to re-think the logic of wrapping yourself in aluminized Mylar
during a thunderstorm.

hmmmmm. I'm rethinking. Yeah, maybe that's not such a good idea in a
thunderstorm.

Thanks,

skip