Mercury is also entering the food chain, thanks to thawing permafrost. The Arctic is home to the most mercury on the planet. The US Geological Survey estimates there’s a total of 1,656,000 tonnes of mercury trapped in polar ice and permafrost: roughly twice the global amount in all other soils, oceans, and atmosphere. Natali explains that, “mercury often binds up with organic material in places where you have high organic matter content… organism’s bodies don’t remove it, so it bio-accumulates up the food web. Permafrost is almost the perfect storm – you have a lot of mercury in permafrost, it is released into wetland systems, those are the right environment for organisms to take them up, and then [it] heads up the food web. That’s a concern for wildlife, people, and the commercial fishing industry.”
Are there some positives of a thawing Arctic? Could a greener Arctic start to see more trees and vegetation take root, sequestering more carbon and offering new grazing land for animals? Osborne agrees that “the Arctic is greening”. But she adds that studies of animal populations actually suggest that, “warmer temperatures also increase the prevalence of viruses and disease, so we’re seeing a lot more caribou and reindeer becoming more sickly as a result of this warming climate… it is just not an environment that is suited to thrive at these warmer temperatures.” Natali also says that many areas are experiencing “Tundra browning”: the higher temperatures lead surface water to evaporate into the atmosphere, causing plants to die off. Other areas are experiencing sudden flooding due to the ground collapsing. “It’s not happening in 2100 or 2050, it’s now”, says Natali. “You hear people say ‘we used to pick blueberries over there’, and you look over there and it’s a wetland.”
Natali doesn’t want to end the conversation on a downer. There is a lot we can do, she says. The fate of the Arctic is not a foregone conclusion: “The actions taken by the international community will have a substantial impact on just how much carbon will be released and how much of the permafrost will thaw. We need to keep as much of the permafrost as we can frozen. And we do have some control of that.” Our emissions cannot remain “business as usual”. The Arctic depends on it. And we depend on the Arctic.
Tim Smedley is a sustainability writer, based in the UK. His first book is Clearing the Air: The Beginning and the End of Air Pollution. Join more than one million Future fans by liking us on Facebook, or follow us on Twitter or Instagram.
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