Asymmetrical Information

Not sure about New York skyscrapers, but golfer Lee Trevino had an interesting theory. He once said that if a lightning storm developed over the golf course while he was playing, he'd simply take his 9-iron and hold it straight up into the air. "Not even God's aim is that good," he said.

Huh? It does. I remember a tour guide at the Empire State Building saying it is hit by lightning over 100 times per year.

It does. Lightning will go towards whatever gets closest to it, since it starts from the sky and forks off into various directions, as soon as it makes a connection with something and closes the circuit between itself and the "ground" (which is going to be anything that touches the ground) it will spend itself and disappear.

In a city like New York the lightning is naturally attracted to tall metal things like the empire state building, the chrystler building and the like. Any tall builidng, heck, most buildings, are designed with lightening rods to appropriately deflect the huge pulse of electricity into the ground and away from anything that can be damaged. So we get tons of lightening strikes all the time in bad weather, it's just we're safely tucked away in big buildings which can handle the blasts.

But we've been having the loveliest storm here, haven't we?

Hmmm, you must not have been looking at the Chrysler Building about 15 minutes ago, like I was...

Why Al? What happened?

Lightning striking a tall building is unlikely to be as visible as lightning striking the ground, both because nobody looks at the tops of buildins as often as they look at eye level, and because the colder air a few hundred feet up doesn't ionize as brightly as the warmer air at ground level.
--G

Well, a few strikes seemed uncomfortably close during that storm...

as mentioned above, lightning rods conduct the current to the ground

benjamin franklin was one of the pioneers of lighting rod technology

no one gets hurt because the path of least resistance is down through the rod and the heavy duty circuit attached to it

when lightning strikes the ground, the current can pass through water puddles or damp ground and hurt people nearby. when it strikes a tree, the trunk frequently explodes (water inside the bark boils, increases pressure and explodes ala pop corn, but with lots of wood shrapnel). The tree can also crack, with the tree falling and causing problems for people nearby

there are many collections of great urban lightning photos. but you do have to be looking way up (or be way up) to see it... a person walking around manhattan normally might not even notice that there was lightning

>Not sure about New York skyscrapers, but golfer Lee Trevino had an interesting theory. He once said that if a lightning storm developed over the golf course while he was playing, he'd simply take his 9-iron and hold it straight up into the air. "Not even God's aim is that good," he said.

Geez, Ed. Lee deserves to have this told correctly, as he was one of the greats (both Golf wise, and humor wise)... What he said was:
"I'll hold up my 1 iron, even God can't hit one of those."

Benjamin Franklin. Lightning rods. You must have cut class a few times in the eighth grade. Bad Jane.

You don't see it from ground level but it strikes Manhattan tall buildings amazingly often almost silently, even when it isn't raining.

I used to have a 14th floor office with south and west looking windows in the 40s, and on hot muggy summer days (like today) when it got late in the afternoon as the sun was getting ready to set, you could watch the lightning strikes come in across the river from Jersey and hit one building after another marching eastward. The people on the ground never knew it.

There's also the faraday cage effect, which protects the people inside the building (also inside cars, airplanes, etc.)

Briefly, when you apply a charge to a conductive object, the charge is evenly distributed over the outside surface and no charge is felt inside. So the current imparted by the lightning (current = flow of charge over time) flows over the skin of the building and the people inside do not feel it -- in fact, could not detect it without sensors on the outside of the building.

When a high-voltage power line goes down, the way they fix it is to put a lineman into a box, lift it off the ground, and charge the box up to the same potential as the line. Then he can handle the 10,000-volt live wire with his bare hands. There's no current flow because there's no difference in potential.

Lots more at How Stuff Works.

Here's another - what do whales and dolphins drink?

"what do whales and dolphins drink?"

Depends.

If they can ram and sink a ship carrying spirits they can drink that. Otherwise, just a plain ol' salt water chaser, neat.

Of course sinking ships by ramming was a lot easier in the days of wooden ships and iron men. My personal opinion is that Moccha Dick (the historical basis for Melville's white whale) developed a fondness for underage Madiera, and that's why he really was ramming ships in the South Atlantic.

17 years ago (egad)I spent a summer working on the national mall in DC (selling ice cream from a cart it so happens) and I got to tell you that when a storm comes along the show is incredible... thankfully between the lightening rods on the buildings and the flag poles around the Washington Monument it was rare that a bolt ever reached the ground or even a tree... only one tree did I see get split in twain.... but they sure lit up the sky!

You mean like this?

IIRC, the Empire State gets hit all the time and if go over there and take the tour they tell you about it. Also, some kid, who did not have enough sense to come in out of the rain, got killed by lightning while watching a thunder storm from the roof of his Manhattan appartment building a year or two ago. I sent the story to the Darwin Awards website at the time, but they rejected it.

What Dr. Manhattan said (my office looks out on the Chrysler Bldg)... I presume Jane's post had something to do with the thunder and lightning passing overhead at the very moment she made the post...

Actually last August (2002) we had a lightning fatality in NYC in Little Italy. ALmost a year to the day now that I think about it - Aug 02, '02. Anyway the three hipsters living in Little Italy went up on their roof to watch a spectacular storm come through. They were on the roof of a 4 or 5 story building but were surrounded by taller buildings and so thought they were safe. They weren't. One dead.

It was a terrible storm. It was raining cats and dogs and hailing cabs.

Actually, while tall buildings get struck often and good lightning rods do contain very stout ground paths just in case, a lightning rod prevents more lightning than it ever takes to the ground.

Theory of charge spheres: Charges build up on a sphere until finally, the charge differential is great enough to ionize the air between them and equalize. Large charge spheres can accumulate many charges before equalizing, hence an intense, high-voltage arc, while small spheres tend to 'bleed' current instead. This can easily be illustrated with an electrostatic generator in a high school physics classroom: Put a grounded metal ball near the generator ball and you get periodic arcs, but hold a metal rod with a pointed tip near the generator ball and the current trickles off with a continous, faint buzzing sound.

This is why lightning rods end in a sharp point (effectively a tiny sphere) and why hikers caught in the open during a storm are advised to crouch in a low area -- you want to be a "small sphere" that is as close to the ground as possible, increasingly the probability that the ground will source an arc instead of you.

I live at the base of a mountain that hosts nearly all of the broadcast radio and television trasmission towers for the Denver front range area, and while we get some spectacular summer thunderstorms, and although the towers are the highest objects in the immediate area, the region within about a mile of the towers almost never takes a hit. The towers are equalizing the charge difference as described above.

Anony-mouse beat me to it. The primary function of lightning rods is to bleed off charge before enough builds up to create a really big and damaging bolt. That is, the rods on the Empire State Building are working overtime, but they draw lots of little sparks, a good many bolts that aren't big enough to catch your attention from the ground, and only rarely a whopper.

Bleeding off the charge doesn't always work. One night back when I was not quite a teen, there was a tremendous flash of light and thunderclap that had my Dad and I both jumping out of bed and looking for where it hit the house, or at least a nearby tree. It turned out to have hit a whole half block away, vaporizing a good lightning rod and ground wire and leaving a streak of burned paint down the gable end of a neighbor's house. There must have been a costly repair bill from that, but a whole lot less than if the bolt had gone through the house.

I used to live around 31st and Lex with a lovely view of the Empire State Bldg, and I can tell you definitely that it strikes tall buildings a lot.

Ed - That's "not even God can hit a one-iron".

You can remember this by the old joke about the guy whose wife asks him to teach her golf so she can join his Saturday foursome:

"Sure honey, take this one iron, 'cause that's the simplest club to hit, and we'll hit it off this downslope...."

Comments are Closed.