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Within the Norwegian mountains, there is still an ice age. Just a few meters below the surface, it has been freezing for thousands of years. Now the mountains are melting.
A sinkhole at Gjelhallet in Sassendalen in Svalbard as a result of the permafrost below the ground surface has melted and the land above has collapsed. Cornelia Jaspers / Norwegian Polar Institute
The frosts have stabilized our mountains, with relatively few landslides even on steep slopes. But the drama of recent years surrounding Mannen og Veslemannen in Romsdal is a warning of what the future will be like.
- Various forms of rockslides and landslides are becoming more common.
- Nature becomes different. Lowland vegetation will take over the mountains.
- Huge amounts of methane will be released and global warming will intensify.
The reason is climate change. Global warming is thawing permafrost in the Northern Hemisphere. It is happening particularly fast in the Arctic because warming there is two to three times faster than the world average.
Permafrost means that only the top layer of rock, soil, or swamp thaws in summer. Below is an eternal frost. Read more here.
Glittertind in 2019. The glacier at the top is gone and Galdhøpiggen is the highest mountain in Norway. Stig Storheil / NVE
Glittertind in 1910. The glacier at the top makes the mountain the highest in Norway. Wilse, Anders beer / Sparebankstiftelsen
“Very dramatic”
Climate researcher Ketil Isaksen from the Norwegian Meteorological Institute is a co-author of this year’s “State of the Weather 2019” published by the American Meteorological Society.
– What is happening is very dramatic. The permafrost is melting more and more and the temperature rises several tens of meters down, he says.
– Little by little we have a good network of measurement stations that record the temperature at great depth in the ground. In many places, the series of measurements go back 40 years. Therefore, we clearly see what is happening. And we see the same trend in Alaska, Canada, Svalbard, Norway and Siberia. Also in the Himalayas and the Alps, permafrost falls to the ground. It creates big challenges for local people, cabin areas, ski lifts and tourism, says Isaksen.
This is a slippage of the active layer (the one that thaws every summer) on the permafrost at Hanaskogdalen in Svalbard. It occurred as a result of record ground temperature in parts of August 2019. Thawing of the upper layer of permafrost leads to slopes becoming more unstable. Combined with heavy rains, the likelihood of these types of landslides, as well as landslides and landslides, increases. Virve Ravolainen / Norwegian Polar Institute
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It means that the water penetrates deeply
Measurements show that the permafrost across Norway is on the verge of collapsing.
– Much of the permafrost in mainland Norway is now close to 0 degrees and will disappear in the next few decades. Perpetual frosts in the mountains of Møre og Romsdal, in Troms, in Dovrefjell, Rondane and Jotunheimen will be exposed to the thaw, believes Isaksen.
The combination of more torrential rains and the melting of the mountains is scary. Until now, the frost on the mountain has protected against the ingress of rainwater. When the frost is gone, the water flows deeper into the rock and can lead to landslides and rock falls.
Much of the continent’s permafrost is in the mountains. But also in the biologically important palsmyrene in Finnmarksvidda, which is our tundra, it is now rapidly thawing. Ketil Isaksen says that the Finnmark plateau is like a miniature Siberia.
Researchers closely follow what happens when organic material frozen on the plateau melts. The big fear is that the extreme amounts in the Siberian tundra will melt and emit a large amount of methane that can further accelerate global warming. Methane is a very powerful greenhouse gas, about 25 times more powerful than CO₂.
Aerial photo of Reindalen in Svalbard with clear signs that ice trucks are melting at the top and that depressions in the landscape are filling with water and eventually turning into ponds and small lakes. You can see a reindeer in the middle of the image. Ketil Isaksen / Meteorological Institute
Permafrost measuring station at Janssonhaugen in Svalbard. The temperature is measured in two wells at 102 and 15 meters deep. They were the first of their kind established in Europe to monitor permafrost and are now an important reference for the condition of permafrost in Svalbard and around the world. Temperature measurements down to a depth of 100 meters show a steady increase since the late 1990s. At a depth of 10 meters, the temperature rise is more than 2 degrees. Ketil Isaksen / Meteorological Institute
Svalbard warmer faster
The “State of the Weather 2019” report describes the events in Svalbard and Alaska as special. In few places do permafrost heat up as fast as in Svalbard, both on the tundra and in the mountains.
In many places you can see traces of soil and slopes that collapse. At various locations in Svalbard, measurements show that the temperature has risen by 0.6 to 0.8 degrees per decade 20 meters underground.
On June 26, 2008, a large landslide occurred at Polvartinden in Signaldalen in Troms. The landslide came very close to taking with it two farms and several cabins where people were staying, and destroyed a large area with cultivated land and farm fields. Researchers from NGI and MET, along with researchers from Canada and Switzerland, have investigated local climatic, frost and geomechanical conditions in the landslide area. The study concludes with the melting of the permafrost in combination with the very hot period before the incident, it appears to have been important in triggering the landslide. Ketil Isaksen
Sensational discovery in Alaska
In Alaska, in 2019 it was shown for the first time that the active layer of the tundra, that is, the layer that normally thaws in summer, does not freeze properly until winter.
– This is a typical sign of a large excess of water and heat in this equipment. The thawing of the permafrost below this layer continues throughout the year. It is usually minus 10 degrees. If this continues for several years in a row, the permafrost will thaw over large areas. It’s a strong warning, Isaksen says.
If the upper part of the permafrost disappears, nature will gradually change. The thrifty plants of the mountains will have to give way to the plants of the lowlands, and the areas of the animals of the mountains will be occupied by species that do not thrive in the cold. Streams and rivers can disappear completely because the water will fall to the thawed ground.
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