Abstract
We applied the principles of visual perception, light, and optics to quantify the influence of ambient sunlight on the ability of skiers and snowboarders to perceive ground contours on a ski slope. To this end, we systematically measured the visibility of the terrain on ski runs under a variety of lighting conditions at Mammoth Mountain in California. Recreational skiers, snowboarders, and ski patrol members were surveyed to determine their subjective ratings of visibility. These subjective visibility ratings for various weather/lighting conditions were compared to quantified on-slope visibility measurements that were obtained using quantitative contrast and luminance measurements. The preliminary results support the objective measure as a tool to objectively quantify on-slope visibility and suggest additional cues skiers/snowboarders may be using to assess visibility. The methodology presented in this paper provides a first step in using software-based image analysis as a tool to predict conditions under which the likelihood of injuries may increase. Ultimately, resorts could use these data to develop methods of enhancing visibility on poorly lit runs before injuries occur.
