Performance of snow density measurement systems in snow stratigraphies

Jiansheng Hao,Lanhai Li,Ting Feng,Richard Mind'Je

doi:10.2166/nh.2021.133

Abstract

Abstract Gravimetric and dielectric permittivity measurement systems (DMS) are applied to measure snow density, but few studies have addressed differences between the two measurement systems under complex snowpack conditions. A field experiment was conducted to measure the snow density using the two measurement systems in stratigraphical layers of different densities, liquid water content (LWC), hardness, and shear strength, and the performance of the two measurement systems was analyzed and compared. The results showed that the snow density from the DMS tended to underestimate by 9% in the dry snowpack and overestimate by 3% in the wet snowpack, expressed as the percentage of the mean density from the gravimetric measurement system (GMS). Compared with the GMS, the DMS has relatively low precision and accuracy in the dry snowpack and similar precision and accuracy in the wet snowpack. The accuracy and precision of the two measurement systems increased with the increase of hardness and shear strength of snow in the dry snowpack, but the accuracy and precision measured of the DMSs increased with the decrease of hardness and shear strength of snow in wet snowpack. The results will help field operators to choose a more reasonable measurement system based on snowpack characteristics to get reliable density data and optimize field measurements.

Highlights

Snow cover is a critical component linking the global climate system and the Earth’s surface system and provides water resources to large populations worldwide (Sturm et al 2002; Barnett et al 2005; Huning & AghaKouchak 2018; Skiles et al 2018)
This study compared snow density measured by gravimetric measurement system (GMS) with a 100 cm3 box-cutter and dielectric permittivity measurement systems (DMS) with Snow Fork in the TSSAR in the winter of 2017–2018
The results showed that the snow density from the two measurement systems was significantly different in the same snowpack

Summary

Introduction

Snow cover is a critical component linking the global climate system and the Earth’s surface system and provides water resources to large populations worldwide (Sturm et al 2002; Barnett et al 2005; Huning & AghaKouchak 2018; Skiles et al 2018). The density is one of the fundamental and important snow properties, which varies over time (Carroll 1977; Conger & McClung 2009; Michele et al 2012) It plays a key role in shaping a wide range of snow properties and physical processes (Bormann et al 2013). Different studies with similar aims often used different measurement systems to obtain snow density, and snow density data from different measurement systems in the same snowpack were significantly different (Hawley et al 2008; Conger & McClung 2009; Bormann et al 2013; Proksch et al 2015). It is difficult to integrate snow density data from different studies with different measurement systems into global databases due to a lack of quality control and assimilation of snow density from different measurement systems (Bormann et al 2013)

Objectives

Results

Discussion

Conclusion