Seminar by Bernd Etelmüller, Professor, Department of Geosciences, University of Oslo, entitled:
Is there permafrost in Gamanjunni and Mannen – New insights from rock wall temperature monitoring, geophysical surveying and numerical modelling
Abstract:
The warming and subsequent degradation of mountain permafrost within alpine areas is an important process influencing the stability of steep slopes and rock faces. The unstable and monitored slopes of Mannen (Møre and Romsdal, southern Norway) and Gámanjunni-3 (Troms and Finnmark, northern Norway) were classified as high-risk sites by the Norwegian Geological Survey (NGU). Failure initiation has been suggested to be linked to permafrost degradation, but the detailed permafrost distribution at the sites is unknown.
Rockwall (RW) temperature loggers at both sites have measured the thermal regime since 2015, showing mean rock surface temperatures between +2.5 °C and -1.6 °C depending on site and aspect. Between 2016 and 2019 we conducted 2D and 3D electrical resistivity tomography (ERT) surveys on the plateau and directly within the rock wall back scarp of the unstable slopes at both sites. In combination with geophysical laboratory analysis of rock wall samples from both sites, the ERT soundings indicate wide-spread permafrost areas, especially at Gámanjunni-3. Rockwall temperatures, together with ERT measurements and modelling of the ground thermal regime strongly indicate, at least locally, the presence of permafrost. Displacement rates show a seasonality, with higher velocities during spring and early summer than the rest of the year, possibly related to snow melting
NB! This lecture is only possible to participate digitally via videolink
Videolink to the lecture will be sent to the mailinglists alle@geo and geohyd-info@geo. If you want to subscribe to the geohyd-info@geo list send an email to Anita.
This lecture use Zoom | Download the Zoom Client for Meetings
About the seminar series
GeoHyd Lunch Seminars are for the time being fully-digital, following the corona guidelines.
This seminar is offered by the Section for Geography and Hydrology, Dept. of Geosciences, University of Oslo. The GEOHYD-seminars are announced as lunch seminars so bring your lunch if you want to.
The seminars are open for everyone interested, and especially students are welcome.
The Lunch Seminar Team
– Louise and Sigrid