DW: Why should we be concerned about warming and thawing in the Arctic?

Hugues Lantuit: Permafrost is frozen ground in the Arctic, and it's currently warming at a fast pace. What we've done in a European Union project is to build for the first time an integrated database on permafrost temperature.

We are also running a project called permafrost research priorities, where we try to identify the priorities for research based on input from all the stakeholders. That includes international organizations and, primarily, residents of the circumpolar north. Residents from northern communities are for instance very interested in what the impact of melting permafrost on northern infrastructure is going to be, like on railways or landing strips, or even houses in northern communities.

So what are the key impacts?

The Arctic is warming at a rate faster than any place on earth. And if you look at the recent findings of the IPCC (a summary of what researchers have been finding all over the world), it says the Arctic is projected to warm at a rate that's going to be much greater than any other place on earth. So the impacts are going to be greater.

There are obviously fewer people living in the Arctic than in other world regions, but that doesn't make it less important. There have been people living there for thousands of years, and we are seeing increasing economic prospects in the Arctic. The issue is that with a warming Arctic, we get a lot of impacts in terms of both navigation, and shipping - we know sea ice is retreating, and that means a lot in terms of access to the Arctic - but also in terms of permafrost.

Permafrost covers an extensive part of the circumpolar north. A lot of cities are built on permafrost, which is currently warming, and the layer that is thawing in the summer is actually expanding and getting deeper and deeper - which threatens infrastructure.

That means severe impacts for several countries with northern territory?

Yes. There are some communities on Svalbard, which belongs to Norway, but most are located in Russia, Canada and Alaska. The way things are approached is scientifically very similar, but societal approaches are slightly different. In Canada we are dealing with a lot of small communities that are located on permafrost, and the way to approach it is often local. But if you look at Russia, you have major cities built on permafrost. Obviously the kind of approach you need there is vey different and requires much more national cooperation.

With regard to the permafrost: do we just have to accept and adapt?

Adapt is the right word. You might talk about mitigation, doing something to stop permafrost from warming. But that's very difficult. Permafrost underlies 44 percent of the land part of the northern hemisphere and you would want to put a white blanket over permafrost, that whole area. That is obviously not possible.

The air temperature is warming in the Arctic, and we need to build and adapt infrastructure to these changing conditions. It's very hard, because permafrost is frozen ground. It contains ice, and sometimes this ice is not distributed evenly under the surface. It's very hard to predict where it's going to be, and thus where the impact will be as the permafrost warms and thaws.

Would a new United Nations climate treaty have any chance at stopping the thawing of permafrost and sea ice in the Arctic?

All negotiations will have an impact. The permafrost is melting because the air temperature is warming. We need to reduce emissions, and actually reduce the temperature change to reduce the thaw of permafrost. Regardless, we know the Arctic is certainly going to warm, and some components will react, like the sea ice; and the vegetation and the ice cap in Greenland, and ultimately permafrost.

This is a major issue, because it contains a lot of what we call organic carbon, and that is stored in the upper part of permafrost. And if that warms, the carbon is made available to microorganisms that convert it back to carbon dioxide and methane. And we estimate right now that there is twice as much organic carbon in permafrost as there is in the atmosphere. So you can see the scale of the potential impact of warming in the Arctic.

Hugues Lantuit is a coastal permafrost geomorphologist with the Alfred Wegener Institute for Polar and Marine Research.