Simultaneous Estimation of Depth, Density, and Water Equivalent of Snow using a Mobile GPR Setup

Thursday, 18 December 2014
Tobias Jonas, Nena Griessinger and Saskia Gindraux, SLF / WSL, Davos Dorf, Switzerland
Terrestrial and airborne laser scanning of snow has significantly increased our ability to improve our understanding of the spatial variability of snow depth. However, methods to provide corresponding datasets of snow water equivalent of similar quality are unavailable to date. Similar to laser scan technology, ground penetration radar (GPR) has become more accessible to snow researchers and is currently successfully used in the context of snow hydrological studies.

GPR systems can be used and set up in different ways to measure snow properties. In this study we elaborate on a mobile GPR system that allows simultaneous estimation of snow depth, density, water equivalent in a snow survey setting. For this purpose we have built a GPR platform around a sledge system with four antenna pairs set up as a common-mid-point array and a separate fifth antenna pair dedicated to analyze the frequency change of the radar signal when propagating through the snowpack. Liquid water content can be accounted for by assessing the frequency dependent attenuation of the radar signal.

We will present data from field campaigns that were carried out in 2013 and 2014 to test the ability of our GPR system to estimate snow bulk properties along several test transects. Along with the results, we will discuss system configuration and post-processing issues.