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BBC – Future – The toxins released by melting arctic ice

In 2012, Sue Natali arrived for the first time in Duvanny Yar, Siberia. So, a postdoctoral researcher studied the effects of thawing of permafrost due to climate change, she had seen pictures of this site many times. Rapid thawing at Duvanny Yar had caused a massive earth collapse – a "mega decline" – like a huge sinkhole in the middle of the Siberian tundra. But nothing had prepared her to see it personally.

As you walk along, you see what looks like logs that damn the permafrost. But they are not logs, they are bones of mammoths and other Pleistocene animals – Sue Natali

"It was incredible, really incredible," she recalls as she spoke to me from The Woods Hole Research Center in Massachusetts, where she is an associated scientist. "I still get chills when I think about it … I just couldn't believe in the size: collapsing rocks the size of several storey buildings … and as you walk along you see what looks like logs that damn the permafrost. But they are not logs, they are bones of mammoths and other Pleistocene animals. "

What Natali describes is the visible, dramatic effects of a rapidly heated arctic. The permafrost ̵

1; until now, permanently frozen soil and soil – thaws and reveals its hidden secrets. Alongside Pleistocene fossils are massive carbon and methane emissions, toxic mercury and old diseases.

The organic rich permafrost contains an estimated 15 billion tons of carbon. "It's about twice as much carbon in the atmosphere and three times as much carbon as that stored in all the world's forests," says Natali. She explains that between 30% and 70% of permafrost can melt before 2100, depending on how effectively we respond to climate change. "70% is as normal if we continue to burn fossil fuels at our current rate and 30% is if we reduce our fossil fuel volumes … Of the 30-70% that defrost, the carbon is closed in organic matter will begin to be degraded by microbes, they use it are fuel or energy, and they release it as CO2 or methane. "

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About 10% of carbon it, the defrost will probably be released as CO2, which represents 130 to 150 billion tons. This corresponds to the current rate of total US emissions each year up to 2100. Melting permafrost effectively introduces a new country at number two on the list of highest emitters and one that is not included in current IPCC models. "People are talking about a carbon bomb," said Natali. "In geological time scales it is not a slow release. It is a pool of carbon that is locked away and is not included in the carbon budget to stay below two degrees (Celsius)."

Northern Hemisphere Winter 2018/2019 was dominated by "polar vortex" headlines, as temperatures dropped in exceptionally far south to North America. In South Bend, Indiana, it reached -29 C in January 2019, almost twice as low as the city's previous record in 1936. However, such stories masked the opposite in the far north in addition to the Arctic circle. In January 2019, the Arctic sea ice also experienced only 13.56 million square kilometers (5.24 million square kilometers), approx. 860,000 square kilometers (332,000 square kilometers) below the average between 1981 and 2010 and only slightly above record high in January 2018.

In November, when the temperature should have been -25 ° C, a temperature of 1.2 ° C above the freezing point was recorded in the North Pole. The Arctic heats twice as fast as the rest of the world (partly due to loss of solar reflectivity).

"We see a large increase in the gap of permafrost," confirms Emily Osborne, program director for the Arctic research program, NOAA, and editor of the Arctic report card, an annual peer-reviewed environmental study of the Arctic. As a direct result of rising air temperatures, she says that the permafrost defrosts and "the landscape physically melts as a result … things change as quickly and in different ways as the researchers had not even expected."

The headline of the Arctic report card in 2017 drew no blow: "The Arctic shows no sign of returning to a reliably frozen region". A paper co-author of Hanne Christiansen, University Center Svalbard, Norway, studied permafrost temperatures at a depth of 20 meters (it is 65ft, far enough down not to be affected by short-term seasonal changes), and the observed temperatures have increased up to 0.7C since 2000 Christiansen, who is also chairman of the International Permafrost Association, tells me "temperatures rise within the permafrost at relatively high speeds … so of course, what was permanently frozen before could be released." In 2016, the autumn temperatures on Svalbard remained above zero throughout November, "the first time this has happened in the records we have going back to 1898," says Christiansen. "Then came large amounts of rain – rainfall here is typically snow … we had mudslides that cross roads to 100 meters … we had to evacuate some parts of the population."

In some places in the Alaskan Arctic you fly over a Swiss cheese of soil and lakes formed by the ground collapse – Sue Natali

The rapid change in North American permafrost is just as alarming. "In some places in the Alaskan Arctic, you fly over a Swiss cheese of soil and lakes formed by landbreaking," says Natali, whose fieldwork has moved from Siberia to Alaska. "Water that was close to the surface, will be now a pond." Many of these ponds bubble with methane, as microbes suddenly find themselves with a feast of ancient organic substances to melt on and release methane as a by-product. "We often go over the lakes because it's so low and it's like you're in a hot tub in some places that are so much bubbly," says Natali.

But methane and CO2 are not the only things released from the once frozen soil. In the summer of 2016, a group of nomadic reindeer dogs began to get sick of a mysterious disease. Smokers began to circulate with the "Siberian plague", last seen in the region in 1941. When a young boy and 2,500 reindeer died, the disease was identified: anthrax. The origin was a defrost of reindeer carcasses, a victim of an anthrax outbreak 75 years earlier. The 2018 Arctic report briefly speculates that "diseases such as Spanish flu, cups or plague that have been wiped out can be frozen in the permafrost." A French study in 2014 took a 30,000-year-old virus frozen in permafrost and heated it up in the laboratory. It immediately came back to life, 300 centuries later. (To read more, see BBC Earth's piece on the diseases hidden in ice.)

The addition of this apocalyptic vision in 2016 makes Doomsday Vault – a sub-permafrost facility in Arctic Norway, which protects millions of seed seeds forever – was broken with melt water. And being listed among the membership of The Global Terrestrial Network for Permafrost, Swedish nuclear waste management, which probably also relies on a permanently frozen permafrost (since BBC Future approached them for comment on this point, did not respond).

Preserved human archeology can also emerge, but just as quickly lost. A frozen Palaeo-Eskimo site in Greenland, preserved for 4,000 years, risks being washed away. This is just one of the estimated 180,000 archaeological sites preserved in the permafrost, often with soft tissues and clothing that remain uniquely intact, but will rot rapidly if exposed. Adam Markham of the Union of Concerned Scientists has said, "With rapid man-made climate change, many places or the objects they contain will be lost before they have been discovered."

However, more modern (and undesirable) human detritus will not tear away: marine microplasty. Due to circular global ocean currents, much plastic waste ends up in the Arctic, where it is frozen in sea ice or permafrost. A recent study of marine microparticles showed that concentrations were higher in the Arctic basin than all other marine areas in the world. Microplastic concentrations in the Greenland Sea are doubled between 2004 and 2015. "Scientists find that these microplastics collect all over the sea and become dumped in the Arctic," Osborne explains. "This is something we didn't realize was a problem. What scientists are trying to figure out now is the composition of these microplastics, what kind of fish are feeding them … and whether we essentially eat microplastics by Eat these fish. "

Mercury also enters the food chain thanks to thawing permafrost. Arctic is home to the most mercury on the planet. The US Geological Survey estimates that a total of 1,656,000 tonnes of mercury is caught in ice and permafrost: about twice the size of any other soil, ocean and atmosphere. Natali explains that "mercury often binds up with organic matter in places where you have a high organic matter content … the organs of the organisms do not remove it to bioaccumulate up on the food network. Permafrost is almost the perfect storm – you have a lot of mercury in it. permafrost, it is released into wet systems, it is the right environment for organisms to pick them up, and then [it] leads up to the food network. It is a concern for wildlife, humans and the commercial fishing industry. "

Are there any positive things about a thawing of the Arctic? Could a greener arctic begin to see more trees and vegetation rooted, sequester more carbon and offer new grassland to animals? Osborne agrees that "arktikken is greener". But she adds that animal population studies actually suggest that "warmer temperatures also increase the incidence of viruses and disease, so we see much more caribou and reindeer getting sick as a result of this warming climate … it's just not an environment there is apt to thrive at these warmer temperatures. "Natali also says that many areas experience" Tundra browning ": the higher temperatures cause surface water to evaporate into the atmosphere and cause plants to die off. Other areas experiencing flash floods resulting from soil collapse. "It does not happen in 2100 or 2050, it is now," says Natali. "You hear people say" we used to choose blueberries over there "and you look out there and it's a wetland."

Natali do not want to end the conversation on a downer. There is much we can do, she says. The fate of the Arctic is not a previous conclusion: "The actions taken by the international community will have a significant impact on how much coal will be released and how much of the permafrost will thaw. We must keep so much of the permafrost as we can frozen, and we have some control over it. "Our emissions cannot remain" business as usual ". Arctic depends on it. And we rely on the Arctic.

Tim Smedley is a sustainability writer based in the UK. His first book is Clearing the Air: The beginning and end of air pollution. Join more than a million future fans by liking us to Facebook or following us on Twitter or Instagram .

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