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Lightning while at the beach

  1. Apr 2, 2007 #1
    It is generally accepted that under lightning risk, it is not safe to be on open areas, and if in such a situation, better to lay on the ground to avoid being the higher feature.

    But what if you are on a beach. Is it safer to keep inside the water than laying on the sand? At the end, the water is better conductor that skin and electricity would be semi-spherically dissipated.

    What do you think?
  2. jcsd
  3. Apr 2, 2007 #2
    I'm betting that's not the safest time to be swimming, for various reasons.
  4. Apr 2, 2007 #3
    okay, but as of lightning, what is riskier or more dangerous, remaining on the sand or inside the water?
  5. Apr 2, 2007 #4


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    I'm not a lightning expert, but in the water you are at risk for the electric current going through your body because of the water being in contact with you. I think your best bet would be to squat down on the dryest and lowest piece of sand you can, and only touch the sand with your feet and keep your feet together touching. That way if there is a ground current, it won't be inclined to go up and around through your body.
  6. Apr 2, 2007 #5
    actually if lihnig is going to hit anywhere near you here's not much you can do to stop it. if the current has gone through a mile of air that extra 6 feet isn't going to make much of a difference.
  7. Apr 3, 2007 #6
    Lie flat on dry sand or better, on a trench in dry sand. This diminishes the risks but not eliminate them.
  8. Apr 3, 2007 #7
    Water increases the conductivity of skin 5-fold. So 10,000 volts becomes 50,000 making it much worse of a lightning strike. Also, water is a much better conductor than SiO2 sand. I'm no expert on the chemistry of sand-to-glass conversion, but glass is a good insulator, which inclines me to believe that sand is likely also a good insulator. For all these reasons, stay on the beach to be safest.
  9. Apr 4, 2007 #8
    Iv been studying the effects of lightning for years. The safest possible way to avoid being struck is to squat down (not lie down) with feet together as Berkeman has already stated above.

    Safer on dry sand than in the water.

    you have a few seconds warning before you get struck, as lightning doesnt travel from the cloud to the ground it actually meets together between the cloud and ground.

    the warning will be a fizzing sound with your hair standing on end the strike will either be extremley close to you or it will hit you. Depends if you generate an electron streamer or not. If u do there isnt much you can do, just brace for it and hope you survive.
  10. Apr 4, 2007 #9
    As water is better conductor than air, and we are better and higher conductor that land, the undelying supposition to the question was that may be in water the lightning would prefer any wave than us.

    So, now, it's clear. Thanks a lot. Hopefully we won't need this new knowledge...
  11. Apr 5, 2007 #10

    In fact, before every lightning strike, several dendrils extend from the ground upwards and the lightning from the clouds comes down to reach one of these dendrils, sometimes only 10 feet above ground level. All the dendrils that don't make contact with the cloud lightning, dissipate and return their electric potential to the earth.
  12. Apr 10, 2007 #11
    Would it help if you stood on the tip of one foot, to minimise the contact with the ground?

    This is just a mad suggestion, but what do you think?
  13. Apr 10, 2007 #12
    No. Not at all.
  14. Apr 10, 2007 #13


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    It depends... If YOU are the lightning rod then no, it will not help. However, if the strike is near by then standing on 1 foot could help. Lighting causes a large voltage gradient in the ground surrounding the area of the strike. If you are standing with your feet on a radial line from the strike your body will bridge different potential lines, causing you to be come a conductor...not good. If you are on 1 foot or standing so you face the strike your feet will be closer to the same potential thus, lower currents will flow through your body.
  15. Apr 10, 2007 #14
    Nothing I can do? If I thought a lightning bolt was about to hit me, I estimate I could move 50 feet in three seconds. If I was standing next to a tree, would running not be worth the effort?
  16. Apr 11, 2007 #15
    No this would not help, you are still earthed to the ground.

    There isnt much you can do if you are producing a step streamer or step leader from your body, thats what i ment, you wouldnt even have time to think about it.

    examples of this phenomenon can be seen here http://www.treecareindustry.org/images/Part4LightningStrike.jpg [Broken]

    This is a famous shot taken by Johnny Autery which shows a tree being struck, as you can see there are 2 other leading streamers that did not manage to find the connection with the main stroke, one from the tree and one from the tv tower.

    If you are on the beach, a number of objects around you may produce one of these streamers. If you are one of them running wont help, you migth be lucky enough not to be directly hit.
    Last edited by a moderator: May 2, 2017
  17. Apr 11, 2007 #16
    What are the chances of surviving a direct hit by a lightning?

    What are the usual health hazards/body impairments for the survivors?

    Also, how exactly does a lightning damage you? Does it fry you up, because of body resistance? I hear different people have different body resistance values: would that affect the chances of being hit and the chances of surviving a hit by a lightning?
  18. Apr 11, 2007 #17
    Some people survive, but maybe not to a direct hit. Lightning and other electric chocks produce heart and/or lung paralysis. This is the reason why you can try to give heart massage and artificial respiration to victims.
    The other possibility is to be fried. Current heats and burns parts of the body. If the current do not goes through the heart, people may survive, seriously impaired.
    People differ on the skin resistance. Mostly due to dry or wet skin. But inside, we are all a very good conducting electrolyte (salted water).
  19. Apr 11, 2007 #18


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    This might sound a bit off the wall, but it's a legit question. I never even thought of it until I read this thread.
    Assuming that you're in the proper crouched position, would it be a good idea to stick your fingers in your ears? I've read several times that the most common complaint of strike or near-strike survivors is deafness from the overpressure. Or would that action increase the chance of the current going through your brain? :confused:
  20. Apr 11, 2007 #19
    Ah, so would that mean that if your skin has low resistance more current will go through it and less through the heart and you're more likely to survive(even though severely burnt)?

    But lightning usually comes with rain, so the chances are: if you're stuck at the open beach you'll be wet anyway.

    Also, would putting an umbrella above yourself increase the chances of you being hit?
  21. Apr 11, 2007 #20
    To whoever answers this: would opening your mouth wide open save you from the pressure?

    Edit: and while we're at it: would riding your unicycle save you? It seems to me the rubber tyres would stop you from being earthed to the ground, so no lightning.
    Last edited: Apr 11, 2007
  22. Apr 11, 2007 #21
    Lightning can strike 10 - 15 miles in front of a storm so doesnt mean you will be wet. But there is high possibility of it raining and being wet.

    But then you may already be wet from swimming, not many people go to the beach and dont go for a swim. but then you can ask yourself why would you go to the beach if there is rain and thunderstorms around.

    And yes an using an umbrella during a thunderstorm will dramatically increase your chances of being struck, just like swinging a golf stick on a golf course and a lightning conductor on a building.
  23. Apr 12, 2007 #22
    If you had an umbrella, I would suggest to use it as an attractor, placing it far from you.
  24. Apr 12, 2007 #23


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    Not sure about the sea... but if swimming in a lake, get out! A lightning strike on the surface may not kill you but can cause temporary paralysis which means you sink...
  25. Apr 12, 2007 #24
    Hmm, this maybe another stupid question, but would a lightning that struck the surface of a small lake cause paralysis to the fishies? If yes, would it endager their lives?
  26. Apr 12, 2007 #25
    Not the fishes in all the lake. It will just harm or kill fishes within 10 or 20 meters of the impact. The current per square meter diminishes as the square of the distance.
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