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Home / World / BBC – Future – The poisons released by the melting of the Arctic ice

BBC – Future – The poisons released by the melting of the Arctic ice



In 2012 Sue Natali arrived for the first time in Duvanny Yar, Siberia. A postdoctoral fellow who studied the effects of the thawing of permafrost due to climate change had seen photographs of this place many times. The rapid thawing of Duvanny Yar had caused a massive burglary – a "mega burglary" – like a huge dump in the middle of the Siberian tundra. But nothing had prepared her to see it in person.

As you walk along, you can see trunks sticking out of the permafrost. But it's not logs, it's the bones of mammoths and other Pleistocene animals – Sue Natali

"It was unbelievable, really unbelievable," she recalls, talking 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 could not believe how big it is to collapse cliffs the size of multi-story buildings … and as you walk along, you'll see tribes stick out the permafrost But they are not logs, but bones of mammoths and other Pleistocene animals. "

What Natali describes are the visible, dramatic effects of a fast-warming Arctic: permafrost ̵

1; previously permanently frozen land and soil – thaws and reveals its hidden secrets: in addition to Pleistocene fossils, there are massive emissions of carbon and methane, toxic mercury and old diseases.

The rich organic permafrost contains an estimated 15 billion tons of carbon. "That's about twice the carbon in the atmosphere and three times that much carbon as in all forests in the world, "says Natali, explaining that 30% b 70% of permafrost can melt before 2100, depending on how effectively we respond to climate change. "The 70% work as usual if we continue to burn fossil fuels at our current rate, and 30% if we significantly reduce our fossil fuel emissions … Of the 30-70% that thaw, carbon deposits in organics are mined by microbes, they use it as fuel or energy and release it as CO2 or methane.

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About 10% of the carbon That is, defrosting is likely to be released as CO2, which amounts to 130-150 billion tons. This is the current rate of total US emissions every year until 2100. The melting of permafrost will put a new country in second place on the list of the highest issuers, and one that is not reflected in current IPCC models. "People are talking about a carbon bomb," says Natali. "In geological times, this is not a slow release. It is a pool of carbon that is locked away and not included in the carbon budget to keep slopes below two degrees (Celsius).

The winter in the northern hemisphere 2018/2019 was marked by "polar vortex" headlines, "as temperatures dropped unusually far south to North America. In South Bend, Indiana, it reached -29 ° C in January 2019, almost double the previous record of 1936. What obscured such stories, however, was that the opposite happened in the far north beyond the Arctic Circle. In January 2019, Arctic sea ice averaged just 13.56 million square kilometers, about 860,000 square kilometers below the long-term average of 1981-2010, and only slightly above the record low in January 2018.

In November, when temperatures were expected to be -25 ° C, a temperature of 1.2 ° C above freezing was measured at the North Pole. The Arctic warms twice as fast as the rest of the world (partly due to the loss of solar reflection).

"We see a sharp increase in permafrost thawing," confirms Emily Osborne, program manager for the Arctic Research Program, NOAA, and editor of the Arctic Report Card, an annual, expert-reviewed, arctic environmental study. As a direct result of rising air temperatures, permafrost is thawing and "the landscape is falling apart as a result … things are changing so fast and in a way the researchers did not even expect."

The title of the Arctic Report Card 2017 has no problems: "The Arctic shows no signs of returning to a reliably frozen region". A study co-authored by Hanne Christiansen, University Center Svalbard, Norway, examined permafrost temperatures at a depth of 20 meters (which is 65 feet, far enough below not to be affected by short-term seasonal changes) and found that temperatures around up to 20 degrees were Christiansen, who is also president of the International Permafrost Association, tells me: "The temperatures in the permafrost rise at a relatively high speed … then of course, what was previously frozen permanently, can be released." 2016 The autumn temperatures in Spitsbergen stayed above zero throughout November. "This happened for the first time in our records from 1898," says Christiansen. "Then came a lot of rain – the rainfall here is typically snow … we had mudslides that crossed roads for hundreds of meters … we had to evacuate some parts of the population."

In some places in the Arctic in Alaska, one flies over a Swiss cheese made from land and lakes, caused by the collapse of the soil – Sue Natali

The rapid change in North American permafrost is equally alarming. "In some places in the Arctic in Alaska, you fly over a Swiss cheese made from land and lakes, which was created by the collapse of the soil," says Natali, whose fieldwork has moved from Siberia to Alaska. "Water near the surface is now becoming a pond." Many of these ponds are bubbling with methane as microbes suddenly consume a feast of ancient organic matter and release methane as a byproduct. "We often go across the lakes because they are so flat and it feels like you're sitting in a hot tub in places. It's bubbling so much, "Natali says.

But methane and CO2 are not the only substances from which the once-frozen soil is released. In the summer of 2016, a group of nomadic reindeer shepherds contracted a mysterious illness. There were rumors about the "Siberian plague", which last occurred in 1941 in the region. When a small boy and 2,500 reindeer died, the disease was identified: anthrax. Its origin was a thrown up reindeer carcass that had been the victim of an anthrax eruption 75 years earlier. The Arctic Report 2018 speculates that "diseases such as the Spanish flu, smallpox or the plague that were extinguished could be frozen in permafrost." In 2014, a French study froze a 30,000 year old virus in permafrost and reheated it in the lab. 300 centuries later it came to life again. (For more information, see BBC Earth's article on the diseases hidden in the ice.)

In 2016, this apocalyptic vision was added to the Doomsday vault – a subpermafrost plant in Arctic Norway that protects millions of harvested seed for eternity – was broken with melt water. Among the members of the Global Terrestrial Network for Permafrost is Sweden's nuclear waste disposal, which is also believed to rely on permanently frozen permafrost (when BBC Future contacted them to comment on it, they did not respond).

The preserved human archeology may also appear, but just as quickly lost. A frozen Paleo-Eskimo site in Greenland, which has been preserved for about 4,000 years, is threatening to be washed away. This is just one of an estimated 180,000 archaeological sites preserved in the permafrost, often with soft tissues and garments that remain uniquely intact, but would quickly rot on exposure. Adam Markham of the Union of Concerned Scientists said: "With rapid, man-made climate change, many places or their artifacts are lost before they are discovered."

Modern (and unwanted) human being However, detritus will not rot: marine microplastics. Due to global ocean currents, a lot of plastic waste gets into the Arctic, where it is frozen in sea ice or permafrost. A recent study of marine microparticles has shown that concentrations in the Arctic Basin are higher than in any other ocean basin in the world. The microplastic concentrations in the Greenland Sea have doubled between 2004 and 2015. "Scientists are finding that this microplastic accumulates throughout the ocean and is dumped into the Arctic," explains Osborne. "This is something we did not recognize as a problem [previously] What scientists are trying to figure out is the composition of these microplastics, which species of fish feed on these … and whether we essentially eat microplastics by eating these fish . "

Mercury also leaks into the food chain thanks to permafrost thawing The Arctic is where most of the mercury in the world is found The US Geological Survey estimates that a total of 1,656,000 tons of mercury are trapped in polar ice and permafrost Doubling the global amount in all other soils, oceans, and the atmosphere, Natali explains: "Mercury often binds to organic matter rich in organic matter, and the organism's body does not remove it and accumulate it in the food web is almost the perfect storm – you have a lot of mercury in the permafrost, it is released into wetlands t, this is the right environment for organisms to ingest, and then [it] it directs the food web. This is a problem for wildlife, humans and commercial fisheries. "

Are there any positive aspects of a thawing Arctic? Could a greener Arctic begin to get more trees and vegetation, bind more carbon and offer new grazing land for wildlife?" Osborne agrees that "the Arctic is getting greener." adds, however, that studies of animal populations actually suggest that "warmer temperatures also increase the spread of viruses and diseases, so we see much more caribou and reindeer get sick due to this warming climate … it's just not an environment It is also suitable for growing at these warmer temperatures. "Natali also says that in many areas a" tundra browning "occurs: the higher temperatures cause surface water to evaporate into the atmosphere and kill plants it due to the collapse of the soil to sudden flooding. "It does not happen in the year 2100 or 2050, it is now, "says Natali. "You hear people say," we used to pick blueberries there, and you look there and it's a wetland. "

Natali does not want to end the conversation with a downer. We can do a lot, she says. The fate of the Arctic is not a matter of course: "The actions of the international community will have a major impact on how much carbon is released and how much permafrost will thaw. We have to keep as much permafrost as we can freeze. And we have some control over it. "Our emissions can not remain" business as usual ". The Arctic depends on it. And we are dependent on the Arctic.

Tim Smedley is a UK-based sustainability author. His first book is Clearing the Air: The Beginning and End of Air Pollution. Join more than one million Future Fans by clicking on Facebook or Twitter or Instagram

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