Study of Snowpack Stratigraphy Using a SFCW Radar (0.6 – 6 GHz): Experimental Measurement and Electromagnetic Simulation.

The characterization of snowpack stratigraphy is essential for understanding the physical processes associated with its evolution, assessing risks and optimizing water resource management. Non-destructive and real-time measurement systems for analyzing the snowpack structure are crucial for this characterization. This study presents reflectance measurements, as a function of the snowpack depth, using a stepped-frecuency continuous-wave (SFCW) radar. This system operates at the AEMET Formigal-Sarrios field laboratory in the Spanish Pyrenees.

The measured reflectance is compared to the simulated reflectance derived from the structure obtained through in situ experimental measurements and simulations performed using the SNOWPACK software. Simulated reflectance calculations are conducted using a matrix-based electromagnetic plane wave model.

The in situ experimental measurements of snowpack structure include the assessment of density, grain type, and hardness. At the same time, local meteorological data is used to determinate the temporal evolution of the snowpack profile through the use of SNOWPACK software. This process generated detailed profiles including density, grain characteristics, hardness and liquid water content (LWC).

The agreement between radar SFCW measured reflectance and the reflectance calculated based on the experimental measured profile and the simulated profile from SNOWPACK demonstrate that this method, which is real-time, non-destructive and doesn't interfere with the evolution of the snowpack, is able to reveal its internal structure with a high level of detail. This makes possible a clear identification of the transitions between layers with different physical properties.