干雪的密度—介电常数模型的比较与评价

Comparison and Evaluation of the Models Connecting Dry Snow Permittivity and Density

探地雷达能够较为高效地得到积雪的厚度,其前提条件是需要得到积雪中的电磁波波速。通常积雪的密度(ρ)和其介电常数(ε)存在相关关系,因此积雪的电磁波波速可以由积雪的密度得到。但是表征积雪密度和介电常数关系的方程多种多样,并且这些模型方程很少给出不确定度,导致选择合适的方程变得相当困难。针对已给出和未给出不确定度的模型方程进行比较,并以实测的实验数据为基础,选择最为合理的密度(ρ)-介电常数(ε)关系模型。

Ground Penetrating Radar (GPR) surveys on snow enable a rapid evaluation of snow thickness but necessitate a measurement of the wave velocity in the snowpack. Such quantity is often evaluated from density measurements, using the relationships connecting snow permittivity and density present in literature. Unfortunately such equations provide different results and are rarely reported with an associated uncertainty, making the choice between different models pretty difficult. In the present work we compare all the equations with uncertainties (when reported), suggesting which model can be considered as the most reliable. Such choice has also been corroborated by the analysis of experimental data.