Electrical Resistivity Tomography data collected at the permafrost-affected and unstable Steintaelli Ridge (3100 m a.s.l., Matter Valley, Switzerland) in the last 13 years were inverted with a 3D time-lapse scheme in BERT. Thanks to the temperature-resistivity laboratory calibration of samples from the site, we propose for the first time a quantification of permafrost volumes inside the ridge and of its changes in the last decade. Our data show 5-year average air temperatures to increase from −3.4°C (2005-2009) to −2.6°C (2015-2019), while simultaneously permafrost volume degraded on average from 6790 m3 in 2006 to 3880 m3 in 2019, a decrease of about 40%.
Our approach represents a fundamental benchmark for the evaluation of climate change effects on bedrock permafrost.
Riccardo Scandroglio recently published these results in a special issue of Near Surface Geophysics together with Maike Offer, Daniel Dräbing (University of Bayreuth / Utrecht University) and Michael Krautblatter. The study has been funded by the IGSSE and the DFG. The paper is open access and available at https://doi.org/10.1002/nsg.12149