High-Resolution Aerial Snowpack Monitoring via Passive RFID (GONDO-RFID)

High-resolution snowpack observations in space and time remain a major challenge in snow science. We present a novel approach that combines geodetic positioning, passive RFID sensing, and aerial interrogation to address this gap. Forty-two RFID tags were deployed along a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$2-\text{km}$</tex> transect with 700 m of elevation range before snowfall. A gondola equipped with a GNSS-IMU system and RFID reader repeatedly passed over the site throughout the winter, completing over 1000 runs. This setup enabled the collection of an unprecedented snow dataset using multiple RFID sensing modes: embedded temperature sensing, signal attenuation for snowmelt detection, and phase-based localization (SARFID) adapted for snow water equivalent estimation. We describe the system design, data characteristics, and demonstrate the sensing potential through selected examples from the 2024-2025 field campaign.