The Washington Post, USA
written by Karin Brulliard
Monday August 29, 2016
The macabre images released Monday by the Norwegian Environment Agency look like something out of a wildlife zombie-apocalypse movie, or the aftermath of a cervid “Game Of Thrones” battle: a treeless landscape dotted with hundreds upon hundreds of reindeer corpses.
The 323 reindeer were killed by lightning Friday, the agency said, in a rare natural massacre that counts as the deadliest lightning strike on record. It took place in a private hunting area of the Hardangervidda mountain plateau in central southern Norway, a verdant and frigid tableau of streams, rocks and glaciers that is home to one of the largest reindeer herds in Europe.
Officials told Agence France-Presse that a gamekeeper stumbled upon the eerie scene Friday and that 70 young reindeer were among the victims. Five animals had to be euthanized, said officials, who told the news service that they were not sure what they would do with the bodies. The gamekeeper told NTB, the Norwegian news service, that samples of the carcasses were sent to a state veterinary institute, which would officially determine the cause of death.
“We’ve never seen anything like this on this scale,” agency official Kjartan Knutsen said.”There were very strong storms in the area on Friday. The animals stay close together in bad weather and these ones were hit by lightning.”
Death by lightning is not terribly unusual, of course. According to the National Weather Service, 32 people in the United States have been unlucky enough to die that way so far this year, and about 350 people here have been killed by lighting since 2006. Guinness World Records says the “worst lightning strike disaster” occurred in 1971, when a bolt took down a commercial airplane in Peru, killing 91 people.
So it follows that animals, most of which spend the majority or all of their lives in the great outdoors, also meet their end this way, though the record-keeping on those fatalities is assumed to be spotty at best.
Cattle and sheep are common victims. Guinness reports that the largest recorded number of livestock killed by a single lightning bolt is 68. They were Jersey cows struck in Australia in 2005. (Three cows were briefly paralyzed but recovered.) In March, 21 cows in South Dakota were killed when lightning struck the metal bale feeder they were eating from, leaving their hulking carcasses frozen in an haunting circle.
Sea lions, caribou and wild turkeys have also been documented lightning victims, as have elephants, antelope, a sort-of-famous TV giraffe and a flock of 52 geese in Canada in 1932. The fowl were collected for “wild goose dinners,” according to a news account turned up by science blogger Darren Naish. Naish noted that most animals are killed by currents that run through the ground, not from direct strikes.
Among the more well-known animal lightning strike victims is a bison who resides at Neal Smith Wildlife Refuge in Iowa. A wildlife biologist discovered the bull, bloodied and emaciated, in the summer of 2013. The reserve decided to “let nature take its course,” according to a U.S. Fish and Wildlife Service account — and against the odds, the bison’s tale had a happy ending.
Nearly three years later, he seemed to be doing just fine, one large hairless patch of shoulder notwithstanding. And he had been given a fitting name: Sparky.
Wire.com
written by Megan Molteni
Tuesday August 30, 2016
LAST FRIDAY, NORWAY’S Hardangervidda mountain plateau looked like what would happen if Miguel Sapochnik directed a holiday TV special. More than 300 reindeer corpses were found piled up and strewn across the mountainside, in a natural massacre that Norwegian officials are calling the deadliest lightning strike in their country’s history. Of course, lightning strikes are not uncommon, nor are animals getting killed by them. Sheep, cattle, bison, geese, elephants, and even seals have been struck down by the dozens. So it’s really the scale of the Norway event that is puzzling experts.
At this time, the Norwegian Environmental Agency has not released details of the investigation, but some scientists are formulating a few theories of their own. And they all involve some very basic principles of electromagnetism.
When Glenn Shaw saw the news from Norway over the weekend, he felt deja vu. A now-retired lightning researcher, he remembered being in a helicopter flying over the Alaska Range back in 1972 and coming upon a similarly grisly scene: 53 dead caribou on the side of a mountain. And there was something else: a central burned area about 15 feet wide, radiating out into nine individual branching spokes in an oval shape, getting smaller as they progressed outward. A Lichtenberg pattern. The tell-tale sign of a lightning strike.
What’s more, he noted that the caribou bodies were consistently located on the burn areas. “You could see them lying right on these torturous paths,” he says. “And the fur by the hooves was a bit singed. It was definitely lightning that killed them. No doubt about it.”
He and a guy from the Alaska Department of Fish and Game wrote up the event for a paper, investigating whether the caribou’s antlers made them more susceptible to the strike. No, they concluded: The antlers would have to be much bigger to have any sort of lightning rod effect. Rather, it was the large horizontal extent of the lightning along the ground that really did them in.
When Shaw saw the photos from Norway, he was struck by how the reindeer were found across a similarly large area—hundreds of feet apart. That could only happen with a massive ground current discharge. And it reminded him of something else the two places have in common. Both locations sit at something called a zero degree isotherm, where the average air temperature hovers right around the freezing point of water. That means that permafrost (soil that’s been frozen for two plus years) occurs a bit deeper down—but near the surface it’s constantly in flux between melting and freezing, depending on the season.
This is important, because while liquid water is a strong electrical conductor, frozen water very much is not. If you were to attach high voltage cables on either side of a block of ice, nothing would happen—electricity just can’t pass through it. In physics, we would say that ice has very high resistance.
When lightning strikes, the current flows into the ground and outward, following the path of least resistance. In a warmer place, the electricity would penetrate deep into the soil and disperse quickly (this is called grounding). But in a place like the Hardangervidda, as the current runs into the soil and hits the permafrost layer, it instead spreads out along the surface of the soil, which is saturated with water from annual cycles of melting—and in this case, the massive rainstorms that generated the lightning strike. So the area that gets zapped is way bigger.
The zap is also way stronger. Voltage, which is equal to current multiplied by resistance, goes up as resistance goes up. So as current from a lightning strike encounters the high resistance of permafrost, it magnifies the voltage experienced by any object that happens to be unlucky enough to be on the surface at the time. Like a herd of reindeer.
And it’s about to get even worse for our four-legged friend.
Reindeer are big animals—the space between their front and back legs is separated by a few feet. That creates what is called a large step potential, basically another voltage increase, within the animal itself. If you’ve got supercharged current running along the ground, it eventually encounters the front legs of a reindeer. The electricity takes the path of least resistance, flows up the front legs, through the body cavity (where we find such vital organs as the heart and lungs), down the back legs and back into the ground. In a human, where the distance between the legs is closer and the path to go from one foot to the other bypasses the heart, you might just get paralyzed temporarily. But for a reindeer, having four legs makes for a lethal dose of electrons. Even if the animal is standing perpendicular to the discharge, it will still go through the heart while traveling from front leg to front leg.
Richard Sonnenfeld, who studies lightning propagation at Langmuir Laboratory, said that when he first saw the news article from Norway he didn’t think it had anything to do with permafrost. “But after digging around a little, I think it might and that’s really interesting,” he says. “There’s no question that resistance increases in frozen soil. And it may have been enough to make just one flash count for a whole lot of carnage.”
Norway has very little lightning activity compared to other parts of the world, 100 times less than Florida, which has the most flashes per square mile in the US each year. So it’s unlikely that anything like this will happen again anytime soon. Except for the fact that climate change is expected to increase lightning strikes by 50 percent over the rest of the 21st century. More extreme weather means more potential energy in the atmosphere—and that’s a recipe for more spectacularly deadly lightning.
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