ON THE ZYRYANKA RIVER, Russia - Andrey Danilov eased his motorboat onto the gravel riverbank, where the bones of a woolly mammoth lay scattered on the beach. A putrid odor filled the air - the stench of ancient plants and animals decomposing after millennia entombed in a frozen purgatory.

"It smells like dead bodies," Danilov said.

The skeletal remains were left behind by mammoth hunters hoping to strike it rich by pulling prehistoric ivory tusks from a vast underground layer of ice and frozen dirt called permafrost. It has been rapidly thawing as Siberia has warmed up faster than almost anywhere else on Earth. Scientists say the planet's warming must not exceed 1.5 degrees Celsius (2.7 degrees Fahrenheit) - but Siberia's temperatures have already spiked far beyond that.

A Washington Post analysis found that the region near the town of Zyryanka, in an enormous wedge of eastern Siberia called Yakutia, has warmed by more than 3 degrees Celsius (5.4 degrees Fahrenheit) since preindustrial times - roughly triple the global average.

The permafrost that once sustained farming - and upon which villages and cities are built - is in the midst of a great thaw, blanketing the region with swamps, lakes and odd bubbles of earth that render the land virtually useless.

"The warming got in the way of our good life," said Alexander Fedorov, deputy director of the Melnikov Permafrost Institute in the regional capital of Yakutsk. "With every year, things are getting worse and worse."

For the 5.4 million people who live in Russia's permafrost zone, the new climate has disrupted their homes and their livelihoods. Rivers are rising and running faster, and entire neighborhoods are falling into them. Arable land for farming has plummeted by more than half, to just 120,000 acres in 2017.

In Yakutia, an area one-third the size of the United States, cattle and reindeer herding have plunged 20% as the animals increasingly battle to survive the warming climate's destruction of pastureland.

Siberians who grew up learning to read nature’s subtlest signals are being driven to migrate by a climate they no longer understand.

This migration from the countryside to cities and towns - also driven by factors such as low investment and spotty Internet - represents one of the most significant and little-noticed movements to date of climate refugees. The city of Yakutsk has seen its population surge 20% to more than 300,000 in the past decade.

And then there's that rotting smell.

As the permafrost thaws, animals and plants frozen for thousands of years begin to decompose and send a steady flow of carbon dioxide and other gases into the atmosphere - accelerating climate change.

"The permafrost is thawing so fast," said Anna Liljedahl, an associate professor at the University of Alaska in Fairbanks. "We scientists can't keep up anymore."

Against this backdrop, a booming cottage industry in mammoth hunting has taken hold. The long-frozen mammoth tusks - combined with Chinese demand for ivory - have imbued teetering local economies with a strike-it-rich ethos. Some people bask in instant money. But others watch in dismay as Siberia’s way of life is washed away.

‘Nature is in control’

The first sign of change was the birds.

Over the past several decades, never-before-seen species started to show up in the Upper Kolyma District, an area on the Arctic Circle in northeastern Siberia 1,000 miles west of Nome, Alaska.

The new arrivals included the mallard duck and barn swallow, whose normal range was previously well to the south. A study published last year by Yakutsk scientist Roman Desyatkin said ornithologists in the region have identified 48 new bird species in the past half century, an increase of almost 20% in the known diversity of bird life.

Then the land started to change.

Winters, though still brutal, turned milder - and shorter. Fed by the more rapidly thawing permafrost, rivers started flooding more, leaving some communities inaccessible for months and washing others away, along with the ground beneath them.

The village of Nelemnoye was cut off for three months in late 2017 when the lakes and rivers didn't fully freeze, stranding residents who use the frozen waters for transport. With the village in crisis, the government dispatched a helicopter to take residents grocery shopping.

Claudia Shalugina, 63, used to teach at the three-story school in Zyryanka, a 90-minute motorboat ride downriver. Around 10 years ago, the Kolyma River washed away a section of Zyryanka, taking Shalugina's school with it.

Satellite images show the loss of about 50 acres of land along the riverside, according to the geographic information firm Esri.

Smoking a cigarette on the porch of the village library, Shalugina offered her own analysis of the changing climate: "I think, 'Lord, it's probably going to be the end of the world.' "

Just downstream from where the Zyryanka River flows into the mighty Kolyma, three huge tractor-trailers stand abandoned on the forested riverbank. Weeds and wildflowers rise up around them. The frozen river, used as a winter ice road, suddenly became too risky to drive on.

Spring had come early this year - again.

"It used to be man was in control," said Pyotr Kaurgin, head of the Chukchi indigenous community in the village of Kolymskoye, on the northern reaches of the Kolyma River. "Now nature is in control."

In the summer, huge blazes tore through Siberian boreal forests, unleashing yet more carbon into the atmosphere. Some scientists fear worsening northern fires are amplifying the permafrost damage. Meanwhile, six time zones away (but still in Siberia) on the Yamal Peninsula, monstrous craters have opened up in the tundra. Scientists suspect they represent sudden explosions of methane gas freed by thawing permafrost.

Outside Zyryanka, a once-bustling farm has given way to a jumbled landscape of dips, bumps, and puddles. The mud road, what's left of it, banks and turns at head-spinning angles, until it runs into a widening pond.

“The earth is slowly sinking,” horse farmer Vladimir Arkhipov said. “There’s more and more water and less and less usable earth.”

The impact on farming has been catastrophic.

Arkhipov produces fermented mare's milk called kumys, a delicacy among the Sakha, a Turkic people who make up roughly half the population of Yakutia. Arkhipov also raises foals for meat, which in Sakha culture is sometimes consumed sliced thin, raw and frozen.

In the past five years, Arkhipov said, he has lost close to four of his 70-odd acres of hay fields to permafrost-related flooding - meaning he can feed three fewer horses in the winter. And during a freak blizzard in late 2017 - an increasingly common occurrence in the region as the climate changes, scientists say - 10 of his horses died.

Due to thawing permafrost - along with the demise of Soviet-era state farms - the area of cultivated land in Yakutia has plummeted by more than half since 1990. The region's cattle herds have shrunk by about 20%, to 188,100 head in 2017 from 233,300 in 2011. Reindeer herds have also declined sharply.

Fedorov and other scientists say the degradation of crop and pastureland caused by the thawing permafrost helped bring about the collapse of the region's agriculture.

Yegor Prokopyev, the retired head of Nelemnoye, says climate change is the latest shock to befall the Kolyma River region. There was communism and forced collective farming. Then capitalism and government cutbacks.

His grandfather, a peasant, was declared an enemy of the working class and sent to one of this region's many gulag prison camps.

"As soon as you start getting used to something, they'll come up with something else, and you have to adapt to everything all over again," Prokopyev said.

Visitors from the Ice Age

The idea that warming brings disaster is ingrained in the tradition of the Sakha people of Yakutia, the region laced by the Zyryanka and Kolyma rivers. An old Sakha prophecy says: "They will survive until the day when the Arctic Ocean melts."

Village elders recalled the phrase after an episode of catastrophic flooding in 2005, according to Susan Crate, an anthropologist at George Mason University, who has long studied climate change in Siberia. The radical transformation underway here, she said, should serve as a warning to people in every corner of the globe.

"Changing our ways is imminent," Crate said.

Over the past 50 years, temperatures in most of Yakutia have risen at double or even triple the global average rate, according to work by Yakutsk-based scientists Fedorov and Alexey Gorokhov. The town of Zyryanka has warmed by just over 2 degrees Celsius (3.6 degrees Fahrenheit) from 1966 to 2016, according to their analysis.

The Post's analysis, which uses a data set from Berkeley Earth, looks further back. It shows that Zyryanka and the roughly 2,000-square-mile area surrounding it has warmed by more than 3 degrees Celsius (5.4 degrees Fahrenheit) when the past five years are compared with the mid- to late 1800s.

Some regions of Siberia bordering on the Arctic Ocean are warming even faster, The Post's analysis shows.

Desyatkin, at the Russian Academy of Sciences in Yakutsk, found that the changes are even more dramatic underground. From 2005 to 2014, his team found, the number of days with below-freezing temperatures three feet below the surface fell from around 230 days a year to 190.

That is significant because enormous wedges of ice lie under Yakutia.

In some parts of the world, permafrost lies in a relatively thin layer just below the ground's surface. But in much of Yakutia, the permafrost is of a special, icy and far thicker variety. Scientists call it Yedoma.

Formed during the late Pleistocene, the Earth's last glacial period, which ended about 11,700 years ago, Yedoma consists of thick layers of soil packed around gigantic lodes of embedded ice. Because Yedoma contains so much ice, it can melt quickly - reshaping the landscape as sudden lakes form and hillsides collapse.

Around Zyryanka, exposed ice wedges glisten along the riverbanks. Their slick, muddy surfaces form ghostly, moonlike grooves. Plant roots dangle like Christmas ornaments from the top layer of soil, left behind as the ice below it melts.

In the 1970s, Desyatkin said, the ground in the Middle Kolyma District, just north of Zyryanka, thawed to a depth of about two feet every summer. Now it thaws to more than three feet. That extra foot of thawing means that, on average, every square mile of territory has been releasing an additional 700,000 gallons of water into the environment every year, according to Desyatkin’s calculations.

Meanwhile, ancient plant and animal remains trapped inside the Yedoma are exposed to nonfreezing temperatures - or even the open air. That, in turn, activates microbes, which break down the remains and unleash carbon dioxide into the atmosphere, especially from the thawing plant material.

Scientists estimate that the Earth's Yedoma regions contain between 327 billion and 466 billion tons of carbon. Were it all released into the atmosphere, that would amount to more than half of all human-caused emissions from greenhouse gases and deforestation between 1750 and 2011.

Prospecting for mammoth

Although the thawing of these ancient remains raises the threat of terrifying consequences, it is, for some, the bright side of climate change.

"The thawing of the permafrost has a very good effect. The mammoth bone comes out and brings us money," said Yevgeny Konstantinov, a newspaper editor in the Arctic town of Saskylakh. "Everyone rides Jeeps now."

In recent years, demand from China has created a booming market for mammoth ivory. People in Yakutia collected almost 80 tons in 2017, according to official figures - a likely undercount, experts say. A Yakutia official recently estimated annual sales to be as high as $63 million.

As the permafrost thaws and riverbanks erode, more tusks will emerge. Though mammoths disappeared from the Siberian mainland some 10,000 years ago, the government estimates that 500,000 tons of their tusks are still buried in the frozen ground.

Supply and demand are so great that some people are collecting mammoth tusks at near-industrial scale. They use high-pressure hoses to blast away riverbanks and hire teams of young men to comb the wilderness for months at a time. People involved in the business, which isn't entirely legal, said some tusk prospectors have deployed underwater cameras and scuba gear.

"You get bit once, you catch the bug. It's like a gold rush," said Alexey Sivtsev, a prospector in Zyryanka who said he is licensed to collect tusks. In the glutted market, Sivtsev said, the price for top-quality tusks has fallen from about $500 a pound five years ago to around $180.

According to Sakha tradition, tusk hunting violates the sacred ground and brings bad tidings. Some Siberians worry that it also draws young people into an underworld linked to organized crime.

"Since all this is connected to criminality, I'm worried that this mafia, as we call it, is getting a basis for existing in our villages," said Vyacheslav Shadrin, who studies northern indigenous peoples at the Russian Academy of Sciences in Yakutsk.

Konstantin Gusev, a hunter in Nelemnoye, is still waiting for his mammoth payday.

Once, he found the tusk of an ancient woolly rhinoceros but threw it away. He later learned that such a find sells for $7,000 a pound, making it among the most valuable animal remains buried underground.

Gusev now has his eye on a strip of riverbank where he found a mammoth tooth. He invested in a water pump and hose to try to uncover what's underneath.

Vanda Ignatyeva, a Yakutsk sociologist, said climate change is leaving people with few choices. "They have to somehow support and feed their families."

‘Trying to survive’

The mammoths aren't enough to keep Gusev in the countryside, however. The hunter said he is moving to Yakutsk to look for other kinds of work.

The ducks and geese are just about gone, he said, possibly moving to new habitats in Siberia as the climate shifts. The sable pelts aren't as thick as they used to be. The shorter winters mean that once reliably frozen-over lakes and rivers are now less predictable, making hunting grounds harder to reach and restricting his ability to get goods to market.

"Something is changing," Gusev said. "People are sitting around, trying to survive."

In Nelemnoye, the population has declined to 180 from 210 in the past decade, according to village head Andrei Solntsev. Just 82 of the residents have work. Many factors are pushing people to move to the city - lack of Internet access, poor flight connections, limited job opportunities - but the uncertainty born of a changing climate looms over everything.

"We're already seeing the phenomenon of climate refugees," Shadrin said.

But "it's not like anyone is waiting for them here" in the city, he said. "No one is ready to help them immediately. . . . They're breaking away, becoming marginals."

And Yakutsk offers no escape from the warming climate.

As the permafrost thaws and recedes, a handful of apartment buildings there are showing signs of structural problems. Sections of many older, wooden buildings already sag toward the ground - rendered uninhabitable by the unevenly thawing earth. New apartment blocks are being built on massive pylons extending ever deeper - more than 40 feet - below ground.

"The cold is our protection," Yakutsk Mayor Sardana Avksentyeva said. "This isn't a man-made catastrophe yet, but it'll be unavoidable if things continue at this pace."

An international team of scientists, led by Dmitry Streletskiy at George Washington University, estimated in a study published this year that the value of buildings and infrastructure on Russian permafrost amounts to $300 billion - about 7.5% of the nation's total annual economic output. They estimate the cost of mitigating the damage wrought by thawing permafrost will probably total more than $100 billion by 2050.

But people here are used to adapting. They survived the forced collectivization of the early Soviet Union. Gulag prisoners taught them to grow potatoes. After the Soviet Union collapsed and the state farms closed, they shifted to a greater reliance on hunting and fishing.

Now, Anatoly Sleptsov, 61, is once again embracing change.

The pastures of the village where he used to live have turned into swamps and lakes. So he moved to firmer ground outside Zyryanka, where he's leveraging climate change to his advantage.

Though Sleptsov's attempt to create an Israeli-style kibbutz failed, he figures the region can profit by marketing Omega 3 fatty acids extracted from its fish.

Meanwhile, his potatoes are flowering earlier. And this year, he started growing strawberries.

"Next thing," he said, "we'll have watermelon."

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