Permafrost temperatures in Europe’s mountain regions are rising steadily, in some cases by more than 1°C over the last decade. A new study published in Nature Communications shows larger and faster changes than before.
A dataset of 64 measurement series from nine European countries, from Svalbard in the far North to the Alps and the Sierra Nevada in southern Spain, on permafrost temperatures in Europe’s mountains has been collected and analyzed by more than 20 permafrost researchers under the leadership of SLF scientist Jeannette Nötzli.
They present their research in a new study published in Nature Communications. The results clearly show for the first time that mountain permafrost is getting warmer throughout Europe. In the last 10 years, the temperature at a depth of 10 meters has increased by more than 1°C at some locations.
“The warming of permafrost in the mountains is significant,” says Nötzli, “and it is observed in all regions, depths and time periods that we have looked at.”
The cold regions where permafrost occurs—the high mountains and the polar regions—react particularly sensitively to climate change. The study now shows that the increase in permafrost temperatures in the mountain regions of Europe is partly similar to that in the Arctic: The researchers observed the greatest warming at the highest and northernmost locations.
When temperatures in the ice-rich permafrost rise toward 0°C, the warming slows down significantly and almost comes to a halt because the energy is needed to melt the ice ground. Once the ice in the permafrost has melted, temperatures rise again.
Thanks to international cooperation, Nötzli and her team were able to draw on decades of data from European mountains, which are measured at a depth of at least 10 meters. “This large data set is unique and highly valuable,” explains Nötzli. Collecting data in harsh and cold mountain environments and over many years is time-consuming work and requires a lot of commitment.
Such time series and their evaluation are an important basis not only for climate research, but also for local authorities. The increasing changes and the potential consequences for natural hazards and infrastructure are a major challenge in many mountain regions.
The researchers say the warming of the permafrost continues. “This can also be seen from the fact that the warming at a depth of 10 meters is stronger than deeper in the ground,” says Nötzli. Further down in the ground, temperatures react to climate change with increasing delay. The observed warming will continue to penetrate to greater depths in the coming decades.
Read more: Noetzli, J. et al, ‘Enhanced Warming of European Mountain Permafrost in the Early 21st Century,’ Nature Communications (2024). DOI: 10.1038/s41467-024-54831-9
This news item was provided by the WSL Institute for Snow and Avalanche Research SLF
Header image: Permafrost borehole on the Schafberg near Pontresina (GR). Credit: Jeannette Nötzli / SLF.
