Climate change is thawing out the Arctic permafrost, a layer of frozen soil vital to many habitats. The known consequences of this trend include possible mercury pollution, bouncy ground bubbles, and gnarly paleontological discoveries. But one factor that hasn’t been widely explored is the risk of melting permafrost to Arctic infrastructure, such as residential properties, oil and gas pipelines, and railways.
Scientists led by Jan Hjort, a professor of physical geography at the University of Oulu, Finland, tackle this question in a study published Tuesday in Nature Communications. The team found that 3.6 million people—three quarters of the current population in the Northern Hemisphere permafrost area—may be affected by infrastructure damage from permafrost thaw.
“This is the first study to explicitly show the amount of fundamental infrastructure potentially at risk across the Northern Hemisphere permafrost area under climate change,” Hjort and his colleagues wrote in the paper. “A total of 69 percent of the pan-Arctic residential, transportation, and industrial infrastructure is located in areas with high potential for near-surface permafrost thaw by 2050.”
The team combined temperature measurements, geospatial environmental data, and climate models to study the potential influence of permafrost thaw on Arctic regions with critical infrastructure.
The most vulnerable areas identified in the paper are home to nearly one million people, and contain 36,000 buildings, 13,000 kilometers of roads, and 100 airports. Some Arctic communities have already witnessed homes crumble as the ground melts beneath them.
Nearly half of “globally important oil and natural gas production fields” in the Russian Arctic are also located in high-hazard zones, the team said, including the Yamal-Nenets region of Siberia which provides a third of the European Union’s pipeline imports.
Transportation infrastructure is another major problem area. “The potential risk to railways appears to be especially high,” the team noted. They cited stretches of the Qinghai–Tibet Railway and the Obskaya−Bovanenkovo railway, the world’s northernmost railway, as being particularly at risk due to permafrost thaw.
Hjort and his colleagues said that these projections are fairly conservative, and that the risks will not be offset by reaching emissions targets set by the Paris Agreement. If those goals are not reached, the potential fallout could be more detrimental to Arctic communities.
“In the majority of these cases, I do not think that people will have to move to another area (even if they are living in the high-hazard areas),” Hjort told me in an email. “But infrastructure probably needs more money for maintenance. Parts of buildings and roads, for example, must be replaced more frequently than normal in these conditions.”
“Of course, in some cases the damage of infrastructure means that people (or activities) will have to move to another location,” he added.
Study co-author Vladimir Romanovsky, a professor of geophysics at the University of Alaska, Fairbanks, shared this outlook. “If ice rich permafrost has already started to degrade, it is difficult to stop the process completely, perhaps just slow it down,” Romanovsky told me in an email. “So eventually, relocation may be imminent.”
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