Tuesday, March 16, 2021

Why you shouldn't stand beneath trees when lightning's around

 

Courtesy of reader A. W., I was given the link to this tweet, which led me to the associated video (by now copied to YouTube, so I can embed it here).



Among the commenters on Twitter was one who traced the location of the incident to Gurgaon in India, via this news report.


A man died and three were injured on Friday in Gurgaon after lightning struck a tree under which they had been standing to avoid getting drenched in the rain. The horrific incident was caught on a security camera.

The incident took place on Friday evening at Signature Villas apartment complex in Gurgaon's Sector 82. The four men were part of the horticulture staff at the residential society.

. . .

One man was brought dead to a local hospital, another was in intensive care with severe burns. Two are out of danger.


There's more at the link.

That's a pretty graphic illustration of the dangers involved.  I recall, during my military training, we were warned in pretty severe terms not to stand beneath trees during thunderstorms, and to avoid being anywhere near armored vehicles as well, as the sheer mass of metal they contained tended to attract lightning strikes.  Those inside were usually OK, thanks to the insulation provided by the tires and/or the grounding effect of the exterior of the metal hull, but if you were next to it when the lightning struck, you might be in trouble.  I can recall at least three incidents where servicemen were killed or severely injured in that way.

Peter


17 comments:

  1. Peter:

    The nerd in me has to respond to this one statement:

    "Those inside were usually OK, thanks to the insulation provided by the tires..."

    No. People inside the FARADAY CAGE are fine because of the metal surrounding them. Tires have nothing to do with it. Do you really think lightening burns its way through a mile or so of air just to be stopped by a few inches of rubber? OK, it won't go through the rubber, it'll just arc to the ground.

    As long as you're inside a metal cage and not touching the outer surface (where the electricity runs) you should be OK.

    Take it from me, I have a degree in science! ;)

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  2. I once served with a guy who had been struck by lightning three times. Whenever he heard thunder, he hid under something, curled up into a ball and cried.

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  3. I took a boating safety class once and the teacher had a saying that has stuck with me. Close to 40 years now.

    He said never get under a tree and never, ever be the tallest thing around. Curl up in a little ball and try to be the smallest, most insignificant target you can.

    I'm not quite in the lightning capital of North America, but I can almost see it from here. Being in boat when lightning is around is terrifying.

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  4. i was in the cp tent when a bolt struck the next company's cp tent over a hundred meters away. my rto was holding the mic, sitting in a metal folding chair. he got a good zap, knocked him over backwards, burned his hand. two niner two antennae really pulls in the signal, lol. sadly it killed a guy in the other tent. had a 1sg get struck while leaning on a tank. two weeks later when ho got out of hospital, he was a totally different person. they had to put him out on a medical discharge. totally changed his personality, mean and ornery from easy going. went down hill from there.

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  5. Short story.

    I was wreck diving in Lake Huron when a storm started to threaten. The captain looked at the storm and said "Not sure about this... if lightening strikes the water we're racing back to shore".

    No sooner were the words out of his mouth than KAZAM! a bolt came down and hit the lake. We raced for shore, top speed. Fortunately, we'd gotten one dive in already.

    Impressive storm too. From the safety of the marina clubhouse we watched lightening flow across the sky in rivers of bolts.

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  6. First time this happened: Trolling in metal boat during bad weather and kept hearing a clicking noise. When I pulled a pole out of the rod holder I got shocked. If you held onto fishing pole it would take about 30 seconds before it would discharge. Same experience in kayak holding onto the graphite poles during storms. There was lightning and thunder very far away. I figured getting shocked like that was a precursor to lightning strike. The bolt of lightning never showed up in any time. Just enough static elec in air the scare me off the lake, right when the fishing got good.

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  7. Real experience:

    The storm had seemingly passed. Sky was clearing, sun was out.
    FLA-BANG!-SH!

    The internal damage (metal skinned building) was slight. Picture knocked off a wall. Maybe a fuse blown. Phone out, fax out - fax power supply was toast.

    External damage was greater. The telco's junction box, what remained of it, was smoking. A vertical transceiver antenna, with proper ground radials... well, some the radials weren't there anymore. Trenches were. Did the copper vaporize? Probably not. But the steam explosion left quite a mark!

    Oh, and there was NO obvious sign of a direct-hit. This was, it seemed, induction something "merely" close.

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  8. Lightning regularly kills entire herds of cattle sheltering under trees from thunderstorms.

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  9. McChuck:"Whenever he heard thunder, he hid under something, curled up into a ball and cried."

    Three times, you can hardly blame him, really.

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  10. One time on the farm we had lightning strike near the house. We had sparks jumping off the propane range in the kitchen, a couple old time glass screw in fuses blew across the basement, and an electric fencer which was in anther building and unplugged was half melted!

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  11. Bullet cams (shooting 1000s of frames per second) have demonstrated that lightning doesn't "strike".

    The current flows up first, from ground to sky.
    Tall things (like tree) facilitate that.
    The return static discharge then travels down the path of ionized molecules back to the origin on the ground.
    Zip-ZAP.

    When you're feeling your hairs stand on end, it's already a done deal.

    GTFO, and away from anything tall, wet, or both.

    Dude I worked on a show with had been standing on wet ground when the crane rig he was 80' away from ventured too close to high tension power lines. 50,000V arced to the rig, then outward.

    Eight surgeries later, his legs still aren't 100%, which isn't surprising since he got cooked up to the thighs.

    50,000V is nothing.
    Lightning is 300,000,000 volts at 30,000 amps.

    In combat, you try to look unimportant.
    In electrical storms, you try to be dry, small, and very, very low.

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  12. Something to consider, you want to be a fair distance from where the lightning hits.

    In the desert where the ground is very dry, with just a thin damp layer from the rain, even at 100 feet from the strike you can be knocked out as the current flows out in the damp layer.

    I was just over 100 feet from the strike and was out for about 10 minutes. Face down I could have died if the spouse hadn't come out and turned me over. The current went another 50 feet past me and fried almost all the house electronics.

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  13. Nitzakhon:

    As long as you are not the path for current you are fine. It matters not if you are inside touching the outer shell "where the electricity runs" or not.
    What kind of "science degree" do you have that would let you think that such a half-assed statement would stand? Political Science maybe?

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  14. @B: I think N was talking about Faraday Cage Effect.

    Being struck by lightning is not on my bucket list.

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  15. @Genji: Correct.

    @B: Masters degree in Engineering, plus a minor in physics in undergrad. GPA > 3.5 in both.

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  16. Lightning storm while anchored out in a sailboat is nerve wracking, especially in fresh water which doesn't dissipate the charge as well as salt water.

    The most exciting thunderstorm was when we were scuba diving in a narrow glacier cut lake in central NY. A thunderstorm came over the western side while we were down. All the fish started swimming crazily, and there was a weird noise that almost sounded like some weird paddle wheel boat was passing by. We popped up to the surface and found we were in the middle of a raging thunderstorm! Being EE's we decided that our heads being the tallest thing on the water wasn't good so we went back down and swam for the beach. When we hit it, we dumped tanks and flippers and ran for the faraday cage of the metal car as fast and low as we could!

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  17. Growing up on the farm, we had more than a few cattle killed by lightning. Most were under trees, one was in a small pond, likely getting a drink.

    Closest I've ever been to a strike was about 200 feet. Downpour started, got into the barn... was standing by a door watching the rain come down and the small creek behind the barn come up, and then FLASH-BOOM!!!! The light was blinding, there was a definite heat pulse, like being near a campfire, and then the sound hit me like doing a belly-smacker into a pool.

    The big old ash tree out in the pasture had been well over 100 feet tall, trunk was 3 to 3-1/2 feet across. It was laying on the ground in pieces, and I neither saw nor heard it fall.

    Anyone who doesn't respect lightning is an idiot.

    ReplyDelete

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