Spotlight on Student Research: Studying the mechanics of blowing snow in alpine terrain


PhD candidate Nikolas Aksamit.

Snow is an important water resource in Western Canada. In alpine regions, the wind redistribution of snow can influence the variability in summer runoff and, in turn, water supplies. As the climate warms, these water supplies from snow covered alpine regions become stressed and communities become more dependent on locally available resources. Therefore, improving the understanding of how changes in climate and weather will affect local water supplies (location, timing and magnitude of spring snowmelt) is becoming increasingly important as the climate warms.

That is where Nikolas Aksamit’s PhD research comes in. Nikolas is examining the physical processes of wind transported snow at a microscale in natural conditions at the Fortress Mountain Snow Laboratory (FMSL) in Kananaskis Valley, Alberta in hopes of improving the understanding of such processes.

Working under the supervision of Dr. John Pomeroy, Canada Research Chair in Water Resources & Climate Change, at the Centre for Hydrology at the University of Saskatchewan, Nikolas’s research aims to address the lack of detailed measurements of blowing snow at the surface of the snowpack during turbulent wind. Such transportation of snow directly above and in periodic contact with the snow surface is called the saltation of snow.

In order to capture the motion and detail of saltating snow, Nikolas used laser-illuminated high-speed videography (>1000 FPS) and 3D ultrasonic anemometry at FMSL to simultaneously measure snow particle and wind speed and direction immediately above the snow surface. This is the first application of high-speed videography in nature to obtain Particle Tracking Velocimetry (PTV) measurements – a laboratory experimental technique which estimates the individual snow particle velocities. Nikolas’s research allows for a unique comparison between observations in alpine blizzards and idealized laboratory experiments. This provides a better understanding of how well laboratories can represent the natural environment with respect to complex atmospheric boundary layer- snow surface interactions.

The snow surface behaves as the lower boundary for wind models in cold regions and in mountainous terrain, so understanding the physical processes at work here is important for understanding both the meteorological and hydrological impacts on local microclimates from climate change. The redistribution of snow by the wind redistributes water resources and causes wind to lose momentum (energy), so improving the understanding of this balance is becoming increasingly important as snow becomes scarcer as a water resource. More accurate models are necessary as communities become more stressed for water supplies and there is an increased need to implement best practices in both agriculture and municipal settings.

Nikolas’s research has been recently accepted and published in The Cryosphere journal. Please visit http://www.the-cryosphere.net/10/3043/2016/ to download the paper. This research was done through the cooperation of Fortress Mountain Resort.

Nighttime laser illuminated particle tracking at FMSL

Fortress Mountain Snow Laboratory, Kananskis Country, Alberta, Canada.