Rapid rock glacier changes in Tana, Finnmark

After launching the fantastic InSAR database (insar.ngu.no) we found a rock glacier at the mouth of Tana river showing high displacement rates (Fig. 1). This rock glacier terminates at 20 m asl, meaning that if it is active, this is the lowest active (i.e. containing permafrost) rock glacier in Norway.

We started monitoring surface changes of the Kristofferskaret rock glacier (not an official name; Fig. 2) in early fall 2020, by laser scans (LiDAR) and drone imagery. We repeated these measurements in fall 2021 and can already see that the rock glacier is moving at decimeter scales, indicating that permafrost is present.

We need a master student to participate in this ongoing research project, by processing the raw LiDAR data and drone orthophotos to DEMs. The DEMs can further be used to identify vertical and horizontal changes in the rock glacier surface. We will visit the rock glacier again in fall 2022, and maybe also use Electrical Resistivity Tomography (ERT) to investigate the subsurface for possible frozen areas.

The master student should be interested in geomorphology, GIS, DEMs, and to understand climate-driven processes in the upper ground. The exact direction of the thesis will depend on the background of the candidate and will be discussed with the supervisors.

Image may contain: Ecoregion, White, Green, Light, Slope.
Fig. 1: InSAR view of the mouth of Tana river. The map shows ground deformation from descending Sentinel-1, and red colours mean higher displacement rates. The Kristofferskaret rock glacier is standing out in dark red colours. The graph shows data from the rock glacier as accumulated deformation between 2015 and 2020. The data is publicly available from insar.ngu.no. Click here for a bigger version.
Image may contain: Bedrock, Slope, Natural landscape, Highland, Terrain.
Fig. 2: The Kristofferskaret rock glacier in an oblique aerial view (norgeibilder.no; 3D viewer). Click here for a bigger version.

 

Tags: geomorphology, geomatics, GIS, DEM
Published Oct. 14, 2021 3:40 PM - Last modified Oct. 14, 2021 3:41 PM

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