Introduction
Last updated on October 6, 2025
The Cryologger Glacier Velocity Tracker (GVT) is a low-cost, open-source GNSS system designed for autonomous glacier deployments. Built around the u-blox ZED-F9P receiver and optimized for low-power operation in extreme polar environments, the GVT delivers a complete positioning and logging solution at a fraction of the cost of commercial alternatives.
Background
Glacier surface velocity is a key variable for understanding ice dynamics, mass balance, and glacier response to environmental forcing. High-temporal-resolution measurements are particularly valuable for detecting short-term variability, including diurnal, seasonal, and event-driven changes in flow.
While satellite-derived velocity products have greatly improved regional and global coverage, in situ GNSS observations remain essential for resolving small-scale features, validating satellite data, and capturing high-frequency fluctuations often missed by spaceborne sensors.
Historically, glaciological GNSS measurements have relied on commercial geodetic receivers that offer centimetre- to millimetre-scale precision. However, these systems are expensive, power-hungry, and logistically burdensome—especially in polar regions where access is seasonal and power is limited. As a result, most Arctic field programs can only support a few stations or short-term campaigns, limiting the spatial and temporal density of observations at a time when increased monitoring is urgently needed.
Design Principles
The GVT is developed in the spirit of open-source collaboration and is guided by several core principles:
- Cost-effectiveness: Utilizes low-cost, off-the-shelf components that reduce overall system cost without compromising data quality.
- Modularity: Designed for flexibility, allowing users to adapt the system to various research needs with minimal effort.
- Ruggedness: Built with durable components suitable for harsh Arctic environments.
- Power efficiency: Optimized for long-term deployments with minimal power draw.
- Ease of use: Does not require specialized tools or training to assemble or operate.
The system is accessible to researchers, educators, and enthusiasts alike. Modularity allows the GVT to interface with a wide range of sensors, giving users control over complexity and functionality.
To promote widespread adoption, all design files—including the bill of materials, schematics, and firmware—are openly shared under the GNU General Public License v3.0 (GPLv3). These resources are available on GitHub: