Althouse: On the strategy of huddling together...

২৯ আগস্ট, ২০১৬

On the strategy of huddling together...

323 reindeer, huddling together in a storm, were struck dead by a single bolt of lightning.

৩৬টি মন্তব্য:

Bill বলেছেন...: I'm reminded of the hot tub scene in Eating Raoul.; ২৯/৮/১৬, ৭:৪৩ PM
Big Mike বলেছেন...: An optimal strategy does not guarantee optimal results in all circumstances.; ২৯/৮/১৬, ৭:৪৩ PM
Paddy O বলেছেন...: This is why I'm not voting for Hillary.; ২৯/৮/১৬, ৭:৪৭ PM
mockturtle বলেছেন...: Wow! I know of herds of cows huddled under a tree getting killed by a single strike but that number is incredible! How sad.; ২৯/৮/১৬, ৭:৪৮ PM
Rob বলেছেন...: All it takes is one damned fool who doesn't keep his head down.; ২৯/৮/১৬, ৭:৫৭ PM
rhhardin বলেছেন...: That's the eggs in one basket effect.; ২৯/৮/১৬, ৭:৫৮ PM
rhhardin বলেছেন...: Non-metallic antlers are available these days, like golf umbrellas use.; ২৯/৮/১৬, ৭:৫৮ PM
MikeD বলেছেন...: They tho't they'd created a "safe space"!; ২৯/৮/১৬, ৮:০১ PM
madAsHell বলেছেন...: We called off the baseball practice when the shadow of thunderhead clouds made the aluminum bats look like antenna.; ২৯/৮/১৬, ৮:০৩ PM
mockturtle বলেছেন...: Sort of like Pearl Harbor, when it was decided to move all the planes into one central airfield to prevent sabotage.; ২৯/৮/১৬, ৮:০৫ PM
YoungHegelian বলেছেন...: That seems like such a large expanse of ground for one bolt to cover. I wonder if the bolt forked multiple times when it hit ground.; ২৯/৮/১৬, ৮:১৭ PM
Wince বলেছেন...: Video reminded me of Jonestown.

And wouldn't it be interesting if the reindeer were killed by a single bolt of lightning because they didn't believe in a cult?; ২৯/৮/১৬, ৮:২৮ PM
traditionalguy বলেছেন...: Thor was marking his territory.; ২৯/৮/১৬, ৮:৫৩ PM
meb বলেছেন...: All it takes is one damned fool who doesn't keep his head down.

@Rob - Says the guy with the big rack; ২৯/৮/১৬, ৮:৫৬ PM
themightypuck বলেছেন...: I'm with YH. I had no idea a bolt of lightning could cover that kind of ground. I'm surprised we haven't had marching band tragedies in this country. Especially in the t-storm prone sections.; ২৯/৮/১৬, ৯:০২ PM
F বলেছেন...: For those of you who don't speak Norwegian, I think "Hardangervidda" translates as: "place of reindeer death".; ২৯/৮/১৬, ৯:২০ PM
rhhardin বলেছেন...: Really close strikes don't make any noise to speak of.; ২৯/৮/১৬, ৯:২২ PM
Marc in Eugene বলেছেন...: I freely admit to being not a little science challenged but really? one lightning bolt (well, 'all dead at the same moment', anyway)? Are reindeer specially conductive of electricity somehow? they don't look 'huddled', they look thrown apart all over the damn place. Time, Huffington Post being the trustworthy news sources that they are, I did wonder, but while the Norwegian text seems also to be going on about the Environment Agency people testing for some disease, I didn't see any indication of doubt that a lightning strike was cause of death.; ২৯/৮/১৬, ৯:২৭ PM
YoungHegelian বলেছেন...: Did a little research on how it could be possible for one bolt to kill over that distance of ground.

From Wikipedia

Ground current or "step potential" – Earth surface charges race towards the flash channel [i.e. what's seen as the "bolt" going up/down --YH] during discharge. Due to the high impedance of the ground, the current "chooses" a better conductor, often a person's legs, passing through the body. The near instantaneous rate of discharge causes a potential (difference) over distance, which may amount to several thousand volts per linear foot. This phenomenon is responsible for more injuries and deaths than the above three combined. Reports of "Tens of cows killed by a lightning strike..." are classic examples

So, I imagine that the ground current rushes in in a circle (i.e. from all points around the bolt) & that circle, depending on the strength of the lightening, can be quite large indeed.

I am, however, open to correction on this matter, since it ain't nowise my bailiwick.; ২৯/৮/১৬, ৯:৪১ PM
MadisonMan বলেছেন...: Evidence that there was only one bolt? None.; ২৯/৮/১৬, ৯:৪৬ PM
Fernandinande বলেছেন...: 56 Elk killed by lightning
"Forty-eight of the elk were grouped together within a 60-foot circumference, five other elk were located 75 feet away and three others were located about 130 feet away from the main group."; ২৯/৮/১৬, ১০:০৩ PM
traditionalguy বলেছেন...: FTR: Thor was the fierce eyed, red haired, red bearded son of Odin. He had it made. He was god of fertility and the god of weather who went about striking his hammer on rocks to emit lightening bolts.

The Norge descendants (Norwegians and Scotsmen) should use him as their football team mascot and watch the delicate flowers in the student body scream.; ২৯/৮/১৬, ১০:০৬ PM
n.n বলেছেন...: Achieving an Acceptable Ground in Poor Soil

I think this explains the necessary conditions to create a surface current. The key issue is an impedance differential where the earth is greater than other pathways in the vicinity.; ২৯/৮/১৬, ১১:১৪ PM
Jay Vogt বলেছেন...: I have it on good authority, that they had just been informed of Norway's need to dip into the Soverign Wealth Fund for about $10B ($2K/Nowegian or $31M/dead reindeer) to balance the budget this year.

Reasons:
1. Single engine economy - high cost petro extraction
2. Negative interest rates - real (in some cases nominal)
3. Social consious investment mandate - ha (see #1 above)
4. Depressed continental property values (bubble and Brexit)

When Norway starts to wobble things are reaching a whole new level of messed up. And, these reindeer knew it.; ২৯/৮/১৬, ১১:৩৬ PM
Marc in Eugene বলেছেন...: Thanks, YH et al; all that was very helpful. "Most cloud to ground flashes only 'strike' one physical location", Wiki says, from which one ought to be able to conclude that some flashes strike more than one, I suppose. The Wiki article has already been edited to include the 'Hardangervidda incident'.; ৩০/৮/১৬, ১২:০৯ AM
Eric the Fruit Bat বলেছেন...: I'm guessing that it's better to die from a lightening strike than from a wolf attack.; ৩০/৮/১৬, ৬:১৫ AM
Curious George বলেছেন...: I take solace that they are now with Harambe.; ৩০/৮/১৬, ৬:২১ AM
Bad Lieutenant বলেছেন...: Also see Inagaddadavida, 1968.; ৩০/৮/১৬, ৭:৪৮ AM
Paul Snively বলেছেন...: This is a pretty nicely done look at the physics of lightning. Note the spread of the negative charge in the ground briefly after the strike.; ৩০/৮/১৬, ৮:৩২ AM
নামহীন বলেছেন...: You say 'strategy' as though any one reindeer knew it had a 'strategy...'; ৩০/৮/১৬, ৮:৩৯ AM
Peter বলেছেন...: Surely Darwinian adaptation doesn't have to work all the time, it just has to at least work better than nothing, most of the time?; ৩০/৮/১৬, ৯:৩৭ AM
Gabriel বলেছেন...: 1) Almost everything you have heard about lightning is wrong; for example it doesn't strike the highest thing. I personally have witnessed lightning strike a short tree at the bottom of a hill, surrounded by taller trees (which is why I started learning about it). Lightning has struck people inside their homes. Lighting strikes frequently travel for miles horizontally.

2) Reindeer huddle together for lots of reasons; generally a good idea when they are in danger, but nothing they did materially affected their chances of being struck by lightning. What the huddling strategy does against predators is it makes an individual reindeer's odds slightly higher relative to other reindeer, than it would if the reindeer were alone. Same reason fish school, and the same reason you don't have to outrun the bear, you just have to outrun your buddy.

3) It's true that huddling is what let the lightning kill them all, but lightning is a sufficiently rare and random event (see my point 1, lightning doesn't follow the "rules" we've all heard about it) that evolving a strategy against it is unlikely, and much lower priority than evolving a strategy to escape wolves or find lichens or whatever it is reindeer do.; ৩০/৮/১৬, ১০:৩৩ AM
Amexpat বলেছেন...: I've heard of large groups of Musk Ox getting killed by lightening because whenever they feel endangered they huddle closely together in a defensive formation on high ground. Smart strategy for wolves, horrible for lightening.; ৩০/৮/১৬, ১০:৩৪ AM
Marc in Eugene বলেছেন...: Lightning is a fascinating phenomenon. I wish I had been so curious forty or fifty years ago in science classes.; ৩০/৮/১৬, ১০:৪৮ AM
mikeski বলেছেন...: ...grandma got her revenge.

Re: YH's ground current; that's exactly what can happen. Electricity following the "path of least resistance" is a rule of thumb. If you put a 50-ohm resistor across a battery, some current will flow through it. If you also put a 5-ohm resistor across the same battery, that doesn't mean all the current moves to the 5-ohm one and the 50-ohm one has no moving electrons. There will just be 10 times more current in the 5-ohm resistor than the 50-ohm one.

So the charge flows through the ground, and through anything sitting on the ground, proportionally to its resistance (handwaving the fact that a lightning impulse is very much more an A/C thing than a D/C thing).

This is why instructions for surviving a tornado when you don't have anything to hide in (caught in your car in the middle of nowhere, for example) are to CROUCH DOWN in a low-lying area. If you get down on all fours, or lie down, the path for that ground wave goes through your heart...; ৩০/৮/১৬, ২:৫২ PM
mikee বলেছেন...: If I crouch down, and the lightning flows through my body frying everything from one foot to the other, I think I'd rather have been lying down so I only died of a heart attack, instead of living with electricuted testicles.; ৩১/৮/১৬, ৪:৪২ PM