EU project maps the consequences of the thawing permafrost

As part of a new EU-funded project, scientists, sociologists and engineers from 12 countries will study the impact of the thawing permafrost on coastal communities in the Arctic, and on the global climate. Researchers from DTU and the Norwegian University of Science—part of the Nordic Five Tech alliance of universities—are participating in the project.

With a duration of five years, this is the first project of its kind integrating natural sciences and social sciences on a large scale. The aim is to improve quality of life for people living in the Arctic. The project is funded via the EU Horizon 2020 research programme.

“Many coastal communities in the Arctic are established on permafrost—permanently frozen ground—but, due to global warming, the permafrost is thawing, melting the ice in the ground. The changes threaten the delicate balance of nature, causing significant subsidence and therefore destroying roads, harbours and homes, putting huge pressure on local communities. In some parts, carrying on with normal life is already proving difficult,” according to Thomas Ingeman-Nielsen, associate professor at DTU Civil Engineering.

Input for a system to support decision-making
While scientists from DTU Civil Engineering and NTNU are leading a work package to study the mutual impacts of infrastructure and permafrost, scientists from DTU Aqua will be examining what happens to the organic carbon that is bound in the permafrost once thawed, dissolved and washed away by rivers. Currently, it is not known whether this mixes in and is diluted in the Arctic Ocean or whether it is broken down by bacteria and returns to the atmosphere as CO2.

Other scientists involved in the project will be examining how the thawing permafrost affects the economy and the basic sustenance of Arctic coastal communities, what impact it has on public health in the Arctic, and how coastal erosion impacts the transportation of nutrients and pollutants into and around Arctic waters.

Together, the scientists will provide input for a system to support decision-making intended to help the authorities in the Arctic to deploy resources where they are needed most critically.

Relocation of settlements
Much of the work for DTU and NTNU takes the form of field studies in Greenland, Svalbard and Canada, together with metrics obtained from aircraft or satellites. In addition, the team will talk to residents and authorities in the Arctic to find out about the consequences of the thawing permafrost on the everyday lives of the local people.

On their travels, the scientists have observed major subsidence damage to roads in many places, which are affected by differential settlements and cracking of the pavements. Landing strips are damaged by subsidence, and harbours are becoming clogged with sand, preventing vessels from docking due to coastal erosion and redistribution of sediment.

In some cases, entire settlements are being relocated because coastal erosion is gnawing into urban areas. Elsewhere, the thawing permafrost is causing subsidence to homes, affecting the foundations, and typically resulting in damages to the building envelope. This may cause moisture problems, which can lead to the formation of fungal mould and constitutes a severe health hazard.

Risk assessment and proposals for new road systems
The scientists aim to develop tools to assess the extent of risk of damage to infrastructure in coastal areas. The team will also present proposals for future construction and refurbishment of roads in response to the rising temperature and changes in the foundation.

“One of the challenges is that there is very little—and relatively unreliable—data available about the prevalence of the permafrost and its characteristics both now and going forward,” Thomas Ingeman-Nielsen comments.

“Based on relatively sparse data, we have to make forecasts and assign probabilities to scenarios, for example about the cost of maintaining a road. That’s why we’re working to develop models that better describe the correlations between the thermal and hydrological conditions, and the mechanical properties of the soil.”