Permafrost warming on temporary hiatus

Researchers believe the cooling trend in the Swiss Alps is the result of two winters with little snowfall Keystone

For the first time since 2009, the warming trend of Alpine permafrostExternal link has been interrupted – albeit temporarily – in rock glaciers, according to Swiss researchers.

In these snow-influenced environments, the ground surface was exceptionally cold due to the long-lasting snow cover in spring 2016 and its late arrival in winter 2016-2017.

The latest results by the Swiss Permafrost Monitoring Network Permos, published on MondayExternal link, show that this marked cooling propagated down to 10 metres (33 feet) and even 20 metres at cold sites such as the Stockhorn mountain (3,400 metres above sea level) in the Baltschieder valley near Zermatt.

However, the brief interruption in permafrost warming can be attributed to very particular climatic conditions. The data likely do not yet fully reflect a heat wave that occurred during the summer of 2017, according to a press release from the Swiss Academy of SciencesExternal link.

Moreover, no change in the warming trend was observed in steep permafrost terrains uninfluenced by snow, the statement said.

Permos systematically documents the state and changes of mountain permafrost in the Swiss Alps. The project, which is co-funded by the government and run by six universities and research institutes, was initiated in the 1990s and implemented 18 years ago.