Identifying operation-specific ski run classes and their acceptability for skiing from avalanche risk management decisions in mechanized skiing

While mountain guides in mechanized skiing operations use a well-established terrain selection process to manage the physical risk from avalanches, the relationship between the acceptability of ski runs for guest skiing and the terrain character is complex. First, this thesis presents a new approach for deriving ski run types from daily terrain assessment records of two operations in British Columbia, Canada. It uses a combination of self-organizing maps and hierarchical clustering to identify groups of runs that have been assessed similarly in the past and organizes them into operation-specific run hierarchies. The thesis then uses this foundation and applies a general linear mixed effects model to explore the relationship between acceptable skiing terrain (i.e., status open) and avalanche hazard conditions. Expressing this relationship numerically provides an important step towards the development of meaningful decision aids, which can assist commercial operations to manage their avalanche risk more effectively and efficiently.