Quantifying snow water equivalent using terrestrial GPR and UAV photogrammetry

Yildiz, Semih and Akyurek, Zuhal and Binley, Andrew (2021) Quantifying snow water equivalent using terrestrial GPR and UAV photogrammetry. Hydrological Processes, 35 (5): e14190. ISSN 0885-6087

[thumbnail of Yildiz_et_al (accepted version)]
Text (Yildiz_et_al (accepted version))
Yildiz_et_al_accepted_version_.pdf - Accepted Version
Available under License Creative Commons Attribution-NonCommercial.

Download (2MB)


This study demonstrates the potential value of a combined UAV Photogrammetry and ground penetrating radar (GPR) approach to map snow water equivalent (SWE) over large scales. SWE estimation requires two different physical parameters (snow depth and density), which are currently difficult to measure with the spatial and temporal resolution desired for basin-wide studies. UAV photogrammetry can provide very high-resolution spatially continuous snow depths (SD) at the basin scale, but does not measure snow densities. GPR allows nondestructive quantitative snow investigation if the radar velocity is known. Using photogrammetric snow depths and GPR two-way travel times (TWT) of reflections at the snow-ground interface, radar velocities in snowpack can be determined. Snow density (RSN) is then estimated from the radar propagation velocity (which is related to electrical permittivity of snow) via empirical formulas. A Phantom-4 Pro UAV and a MALA GX450 HDR model GPR mounted on a ski mobile were used to determine snow parameters. A snow-free digital surface model (DSM) was obtained from the photogrammetric survey conducted in September 2017. Then, another survey in synchronization with a GPR survey was conducted in February 2019 whilst the snowpack was approximately at its maximum thickness. Spatially continuous snow depths were calculated by subtracting the snow-free DSM from the snow-covered DSM. Radar velocities in the snowpack along GPR survey lines were computed by using UAV-based snow depths and GPR reflections to obtain snow densities and SWEs. The root mean square error of the obtained SWEs (384 mm average) is 63 mm, indicating good agreement with independent SWE observations and the error lies within acceptable uncertainty limits.

Item Type:
Journal Article
Journal or Publication Title:
Hydrological Processes
Additional Information:
This is the peer reviewed version of the following article:Yildiz, S., Akyurek, Z., & Binley, A. (2021). Quantifying snow water equivalent using terrestrial ground penetrating radar and unmanned aerial vehicle photogrammetry. Hydrological Processes, 35: e14190. doi: 10.1002/hyp.14190 which has been published in final form at https://onlinelibrary.wiley.com/action/showCitFormats?doi=10.1002%2Fhyp.14190 This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.
Uncontrolled Keywords:
?? digital surface modeldigital terrain modelground penetrating radarphotogrammetrysnow densitysnow tubesnow water equivalentunmanned aerial vehiclewater science and technology ??
ID Code:
Deposited By:
Deposited On:
26 Apr 2021 10:20
Last Modified:
05 May 2024 00:30