Ice safety in reindeer herding

The risks for Sami reindeer herders who use snow and ice tracks every day are increased by global warming in the Arctic. This project explored the potential for conducting an operational assessment of ice quality using three different methods with a commercial drone.

The Arctic is warming at a rate three times faster than the global average. One effect is that traditional knowledge about ice conditions becomes unreliable. This severely increases the risk for Sami reindeer herders who use snow and ice tracks every day for their own transport, to transport goods and for reindeer passage. As commercial drones are increasingly being adopted by the reindeer herding community, this project explored the potential for conducting an operational assessment of ice quality using three different methods with a commercial drone. The project was conducted in collaboration between LTU and Dálvvadis Ekonomisk Förening, which consists of four Sami villages surrounding Jokkmokk.

Method A

The first method, A, was based on a visual inspection of the ice using a live video feed from the drone. The collected data was then displayed and discussed at two workshops in Jokkmokk, organized by Dálvvadis Ekonomisk Förening.

A group discussion revealed that reindeer herders do use drones to complement the assessment of ice quality using more traditional methods, such as using an ice axe and drilling the ice. This is particularly true during the spring and fall when the ice is not covered by snow and it is possible to visually check the overall coverage of the ice on lakes and seas. Additionally, a visual overview can be used to find the optimal and safest path over the ice. However, reindeer herders shared many drawbacks of this method (e.g., as shown in the picture, it is difficult to estimate whether the dark surface is open water or clear ice).

Method B

For the second method, B, we developed and tested a drone equipped with a lightweight ultra-wideband pulse radio radar that can remotely scan snow and ice. The prototype allows users to fly slowly over water and monitor the thickness of the snow and ice surface under the drone. The radio reflections from the ice and water surfaces can then be monitored over a 4G modem connection on the drone.

The radar drone has shown great potential in estimating both ice thickness and snow depth. There are some challenges that need to be addressed in order to gain wider adoption among the reindeer herding community. The first challenge is the overall cost and availability of such radars. The second challenge is the interpretation and analysis of collected data, which requires a deep understanding of radio radar technologies. The third challenge is the handling of such hardware in the harsh conditions of the cold Arctic winter. To address these challenges, the radar unit design will be made more robust and user-friendly.

Method C

For the third method, C, we developed and tested a prototype of a submerged ultrasonic buoy that can measure ice thickness. In order to collect data from this underwater buoy, the drone was equipped with Dálvvadis' custom-built radio receiver. This method proved to be very useful and feasible as it allows long-term collection of ice thickness data and other relevant meteorological parameters. To ease access to and sharing of ice thickness information, the buoy was integrated into the reindeer herders' custom-built reindeer tracking app, Nomatrack. The key challenges that remain include radio communication on heavily regulated accumulation lakes, where need be anchored more than 10 meters below the water surface, and reducing the cost of the buoy to allow for more densely-spaced measuring locations on ice tracks.