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When Lightning Strikes
ctwxman writes "For most of the United States (sorry West Coast), this is the season for lightning. It is as powerful as it is spectacular to look at. It is destructive too - by itelf or through the hail, straight line winds and tornadoes that often accompany it. As someone who forecasts the weather, I'm often asked about lightning. As you might imagine, there's plenty to see about lightning on the Internet. The conditions necessary and a little bit of the physics behind lightning are explained by Jeff Haby, a meteorologist (one of my professors actually) at Mississippi State University. Once forecasters get a handle on what's going on, they put the word out through the Storm Prediction Center. Regular outlooks are issued by SPC for severe storms. Once those storms rear their ugly heads, they're followed with mesoscale discussions looking at the active areas. The Storm Prediction Center is also the place where Severe Thunderstorm and Tornado Watches are issued and storm related damage reports are compiled. Lots of hobbyists like to track lightning strikes on their own, and there's equipment available to do just that. Getting hit by lightning is never fun, though not always fatal. National Geographic chronicled an amazing story of a lightning strike, and rescue, on Grand Teton."
For a bit of fun, you can check out the National Lightning Detection Network, which shows recent lightning strikes in the USA over the last few hours.
The first link is a little scant on details...if you're really interested in lightning I'd recommend this.
Don't forget the New Mexico Tech Lightning Mapping System. Here's the link http://ibis.nmt.edu/nmt_lms/
It has some pretty neat images of their lightning mappings. You can see the lightning in 3D, and the precursors to lightning, etc.
Not much info, but there's been some really neat research going on out there. Maybe someone else knows more.
Incidentally, University of Arizona is where E. Philip Krider works in the Department of Atmospheric Sciences - he basically spearheaded the development of lightning detection systems. Coincidence? Probably not.
What you probably experienced was the resulting radio waves that are emitted when the charge from a bolt of lightning enters the ground (though you probably only got a mild version of this).
This is why people are discouraged from "seeking shelter" under large trees during a lightning storm. Not only is the taller object more likely to be struck by lightning, but also the radio waves emitted within a 10-15 ft radius can cause you to go into cardiac arrest. Dangerous stuffs if you're too close to the strike point.
You're spot on. In fact some of the biggest iron in the top 500 are simulating weather.
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Err... no.
There is a great big electric field associated with a nearby channel, and field gradients can result in some really interestingly large voltages to appear across things like the ground.
However, to call these fields radio waves implies that they are oscillatory in nature, which is simply not accurate. I'm a lightning researcher, and in the course of my work I've studied lightning electric fields recorded during close lightning strikes. It's not my personal favorite area of interest, but I know enough to say that "radio waves" is a poor description.
The reason that you don't stand near trees during an electrical storm is because 1) the flash is likely to initiate a side channel which passes from the tree-trunk (radio tower, light pole, bus stop, etc) through you, making you very unhappy; and 2) because the HUGE injection of current into the ground causes the ground itself to "rise" from a nominal 0 volts to several kilo- or even mega-volts, and that voltage falls off as the square of the distance... so that if your two legs are 10 feet and 12 feet respectively from the channel termination point, you might experience a voltage of several kV (or more) between them. This causes a current to flow up one leg and down the other, and makes you (and your goodies, don't ya know) very unhappy. This is worse if you happen to have four legs which CAN'T be placed together, like if you're a cow or horse. Zap!
Ce n'est pas un vrai mouvement de robot!
Chlorine in a pool exists as some sort of ion,
so it carries a charge. Prior to a lightening strike
or near-strike, you get weird effects on the target
from charges building up. If one half of the
chlorine compound (the + or - ion) got pulled to
the surface by this, you might well see some effects.
When I said West Coast, I meant just that - the coast. Please check this map to see how you rate with thunderstorms
As a floridian, I have been zapped via a lightening ground strike while holding a sattelite multiswitch, it actually got an arc going between my hands and the multiswitch, thought I was dead......
As far as the car thing goes, well I actually know someone firsthand who lost all four tires on the sawgrass expressway at speed when struck by lightening, car was totaled......so I'd have to say no it's not bullshit...
If you live in Florida and it's your time to go it will get you, one of my childhood friends lost his father to a lightening strike, a maint worker at my mothers work had all the clothing blown from his body and his head ruptured due to the strike, it's frequently on the news down here how someone died due to a strike, the details of what happens to people when struck are usually far to gory to put on tv, dead on strikes turn people inside out.
Microwave equipment has little trouble from the antenna itself. The culprits are mostly power cables and antenna feed lines, neither of which is a concern for a laptop running on batteries and using a built-in WiFi antenna. Anything close enough to hurt the laptop poses serious risks to you.