A laser-operated probe being developed at the University of Utah could help identify potential avalanche zones, its developer says.
Contained in a brass pipe 9 feet long, the device will be able to detect potential avalanches by analyzing the shape and makeup of snow crystals.The probe and its laser light are inserted into the snowpack to examine the areas beneath the surface for suspect formations.
The probe was designed and built by Rand A. Decker, assistant professor of civil engineering, and Bulent Sensoy, a senior in electrical engineering. It will eliminate manually digging deep pits to examine snow crystals and snow grains at ground level.
Avalanche experts believe unstable layers of ice grains that develop deep within mountain snow cause most large slides. Such crystals are called "depth hoar" because they are formed from heat and rock buried in the snow, which in late autumn are warmer than the surrounding air.
"We want to delineate areas of potential avalanche hazard," Decker said Monday. He is also studying how aircraft airfoils perform during takeoffs and landings in rain and snow blizzards.
To accurately predict avalanches, experts require as much meteorological data as they can obtain, including the structure of the snowpack at ground level, Decker said.
The device was tested on snowpack at the Alta ski resort in Little Cottonwood Canyon and has apparently been successful in analyzing snow types beneath the surface.
"We want to develop a laser probe that would allow an avalanche forecaster to simply stand on the surface of the snow and drive the point of the probe partially into the snowpack to take a reading of the structure of the snow crystals below," said Decker, who is director of science at the non-profit Center for Snow Science at Alta.
Over a period of time, snow grains change size, from fine crystals as the snow falls, to very coarse, unbonded "sugar snow" at the ground's surface, said Decker. It's the unstable sugar snow that can cause slides, he said.
Avalanches usually result from heavy snowfall atop an insecure mass of snow on the ground. Loud noises or other shock waves can trigger a slide, he said.
The instrument still needs some refinements, Decker said.
"Right now our experimental instruments provide us with only a direct reading," Decker said. "But we hope to develop a means of continuous readings of relative reflectants vs. snow depth."