Continuous monitoring of snowpack displacement at high spatial and temporal resolution with terrestrial radar interferometry

Abstract

Terrestrial radar interferometry is used in geotechnical applications for monitoring hazardous Earth or rock movements. In this study, we use it to continuously monitor snowpack displacements. As test site, the Dorfberg slope at Davos, Switzerland, was measured continuously during March 2014. The line of sight displacement was retrieved at a spatial resolution of millimeter to centimeter and a temporal resolution of up to 1min independent of visibility. The results reveal several temperature-driven diurnal acceleration and deceleration cycles. The initiation of a small full-depth glide avalanche was observed after 50cm total differential displacement. The maximum measured displacement of another differential glide area reached 43cm/h without resulting in a full-depth avalanche even after a total measured differential displacement of 4.5m. In regard of the difficulty to predict full-depth glide avalanches on the regional scale, the presented method has big potential for operational snow glide monitoring on critical slopes.