1 Hit in 0.053 sec

Measuring snow water equivalent from common-offset GPR records through migration velocity analysis

James St. Clair, W. Steven Holbrook
2017 The Cryosphere  
<p><strong>Abstract.</strong> Many mountainous regions depend on seasonal snowfall for their water resources. Current methods of predicting the availability of water resources rely on long-term relationships between stream discharge and snowpack monitoring at isolated locations, which are less reliable during abnormal snow years. Ground-penetrating radar (GPR) has been shown to be an effective tool for measuring snow water equivalent (SWE) because of the close relationship between snow density
more » ... tween snow density and radar velocity. However, the standard methods of measuring radar velocity can be time-consuming. Here we apply a migration focusing method originally developed for extracting velocity information from diffracted energy observed in zero-offset seismic sections to the problem of estimating radar velocities in seasonal snow from common-offset GPR data. Diffractions are isolated by plane-wave-destruction (PWD) filtering and the optimal migration velocity is chosen based on the varimax norm of the migrated image. We then use the radar velocity to estimate snow density, depth, and SWE. The GPR-derived SWE estimates are within 6<span class="thinspace"></span>% of manual SWE measurements when the GPR antenna is coupled to the snow surface and 3–21<span class="thinspace"></span>% of the manual measurements when the antenna is mounted on the front of a snowmobile ∼ <span class="thinspace"></span>0.5<span class="thinspace"></span>m above the snow surface.</p>
doi:10.5194/tc-11-2997-2017 fatcat:wiuewmjqcvehnjk4f4uzi7p4i4