In mid-April, a team of scientists and technicians from the University of Alaska Fairbanks and Boise State University ventured onto the frozen Beaufort Sea near Utqiagvik, Alaska, to conduct research using drones. Their mission was to test a new instrument called the Lightweight Airborne Snow and Sea Ice Thickness Observing System, which aims to measure sea ice thickness and snow depth simultaneously.
The LASSITOS project, funded by the National Science Foundation, is led by UAF Geophysical Institute Research Professor Andy Mahoney. Mahoney explained that while satellites are effective at determining sea ice coverage, measuring the thickness of that ice remains a challenge. The LASSITOS instrument package, deployed by drones, seeks to address this issue by collecting data over large areas.
Achille Capelli, a postdoctoral fellow at the Geophysical Institute, designed and built the electromagnetic induction instrument used in the project over the past three years. The LEM, weighing about 10 pounds, consists of a signal generator, transmitter antenna, receiver, digitizer, data logger, and laser altimeter. It measures the distance to the ice-water interface and the snow or ice surface, with the difference between these measurements corresponding to the total thickness of ice and snow.
The drone work was accompanied by ground truth tasks to validate the airborne data, including augering ice holes to measure ice thickness, water depth, and ocean salinity, as well as using a magnaprobe to measure snow depth and ice topography. Boise State University provided a drone and pilot for the snow depth component, along with a ground-level snow-penetrating radar attached to a snowmachine for additional data collection and validation.
Matthew Westhoff, a veteran UAF drone pilot, piloted the drone carrying the LEM during the testing missions. Despite the challenges posed by wind and the payload swinging in significant wind, Westhoff expressed his love for flying in unique locations like the Arctic. The two drone pilots, Westhoff and Thomas Van Der Weide from Boise State, worked in tandem to ensure the success of the flights.
Professor Mahoney is also monitoring work for three other projects funded by the Army as part of the Integrated System for Operations in Polar Seas program. These projects involve researchers from the Geophysical Institute and UAF College of Fisheries and Ocean Sciences and focus on various aspects of the Arctic coastal environment, including optimum travel routes across sea ice, the stability of landfast ice, and small-scale deformation when drifting pack ice interacts with landfast sea ice.
The mood among the research team was upbeat as they made the most of the favorable weather conditions on the Beaufort Sea. With high winds expected in the following days, the team worked diligently to accomplish as much as possible while the weather cooperated. The LASSITOS project represents a significant step forward in understanding the fundamental properties of Arctic sea ice and developing tools to measure them accurately at regional scales.
